Pulm Flashcards

Question

How do PO2 levels affect pulmonary and systemic circulations?

Answer 1

PO2 exerts opposite effects on pulmonary and systemic circulation. In the lungs, a decrease in PO2 causes hypoxic vasoconstriction, shifting blood away from poorly ventilated to well-ventilated regions. In the systemic circulation, hypoxia promotes vasodilation not vasoconstriction hypoxia promotes vasodilation to get oxygen to tissues. Constriction is to divert blood away. It is important for the blood to be distributed to those segments of the lungs where the alveoli are best oxygenated. When the oxygen tension of the alveoli decreases below normal, the adjacent blood vessels constrict causing their resistance to increase as much as fivefold at extremely low oxygen levels. This is opposite to the effect observed in systemic vessels, which dilate in response to low oxygen (opposite of pulmonary vessels).

Answer 2

At high volumes, pressure on alveolar vessels causes them to collapse, raising PVR. At low volumes, traction on extra- alveolar vessels is absent and vessels collapse, raising PVR. The lowest PVR is at FRC.

Answer 3

PAO2 = .21 (Patm - 47 mmHg) - (PaCO2/.8)

Answer 4

Ideally, ventilation is matched to perfusion (V/Q=1) for adequate gas exchange Lung zones: Apex of lung- V/Q=3 (wasted ventilation) Base of lung- V/Q=0.6 (wasted perfusion) V/Q > 0 = airway obstruction (shunt). In shunt, 100% O2 does not improve PO2 (eg A-v malformations) V/Q > infinity = blood flow obstruction (physiological dead space). 100% O2 does improve PO2 assuming <100% deadspace Zone 1 - PA> Pa>Pv (no blood flow -alveolar is better) Zone 2 - Pa>PA > Pv Zone 3 - Pa > Pv > Pa

Answer 5

Symptoms: shortness of breath, dry cough, fever, reduced exercise performance, weakness and lethargy 36-72 hours after arrival. ``` Physical signs -tachypnea -tachycardia -cyanosis +/- rales -loud P2, RV heave ```

Answer 6

1. Immediate -Hyperventilation leading to respiratory alkalosis - decreased atmospheric pressure decreases alveolar oxygen tension. To compensate, decrease alveolar carbon dioxide levels would correspond to an increase in PAO2. The alkalosis, increased pH, favors oxygen loading at the alveoli 2. Days: Increased 2,3 DPG - doesn’t shift the whole curve but shifts the setpoint to the right. Increases oxygen unloading in tissues 3. Days to weeks Kidneys increase level of erythropoietin, which stimulates he bone marrow to increase RBC and hemoglobin levels> thereby increasing oxygen content of blood.

Answer 7

1. Nifedipine 2. Sildenafil * *3. Acetazolamide - two days before a hike. It gives you a metabolic acidosis so when you are on the hike you can exceed levels of ventilation you could’ve had without it. - inhibiting bicarb reabsorption

Answer 8

1. Bronchitis (acute or chronic) - 60-70% of cases 2. *(Bronchogenic carcinoma), endobronchial metastatic tumor, Karposi’s sarcoma, bronchial carcinoid - 23% of cases 3. Bronchiectasis (inflammation of airways; cystic fibrosis)

Answer 9

Increased rate and DEPTH of breathing This is associated with *ACIDOSIS Hyperpnea

Answer 10

FA: May be associated with Central Sleep apnea Constant rate of breathing with variable depth include apneic period (aka suspension of breathing) Causes: 1. neurologic disorder (cerebral hemorrhage) 2. **Congestive heart failure (around 40% of CHF patients will have this kind of breathing at night 3. High altitude and normal aging

Answer 11

Expiration 1. Abdominal muscles (rectus abdominis) 2. INternal intercostals Inspiration: 1. Sternocleidomastoid 2. Scalenes 3. Trapezius 4. EXternal intercostals In COPD, it is difficult for air to get out. Therefore you need to use these accessory muscles. If a patient is using their accessory muscles and has obstructive pattern on pulmonary test they likely have COPD.

Answer 12

Associated with respiratory fatigue or diaphragmatic weakness So basically with normal breathing the abdomen extends outwards with chest expansion. In this case the abdomen goes inward. The accessory muscles are pulling allowing the chest to rise but pulled with it is the diaphragm, pulling the abdominal contents up with it.

Answer 13

1. α1-Antitrypsin deficiency results in excess elastase activity, which can cause emphysema. (can be congenital or from free radicals of tobacco smoke or neutrophils) - In lungs, reduction in α1-antitrypsin leads to uninhibited elastase in alveoli leading to reduced elastic tissue > panacinar emphysema. 2. Centriacinar—associated with smoking. Frequently in upper lobes (smoke rises up). Panacinar—associated with α1-antitrypsin deiciency. Frequently in lower lobes. 3. Enlargement of air spaces, decreased recoil, increased compliance, decreased DLCO from destruction of alveolar walls. INcreased elastase activity > increased loss of elastic fibers > increased lung compliance. ``` CXR: increase AP diameter, flattened diaphragm, increasd lung ield lucency. Barrel-shaped chest Exhalation through pursed lips to increase airway pressure and prevent airway collapse. ``` [class notes] Trapped air---hyperinflation and overdistention •  As more alveoli coalesce, blebs and bullae may develop •  Destruction of alveolar walls and capillaries---reduced surface area for O2 diffusion (hence the major difference with asthma which is that emphysema has a diffusion problem too) •  Compensation is done by increasing respiratory rate to increase alveolar ventilation •  Hypoxemia and hypercapnea usually develops late in disease - results from hypoventilation and increase airway resistance and problems with alveolar gas exchange) •  Minimal coughing with no to small amounts of sputum •  Overdistention of alveoli causes diaphragm to flatten and AP diameter to increase Complications •  Pulmonary hypertension (pulmonary vessel constriction d/t alveolar hypoxia and acidosis) •  Cor pulmonale (Rt heart hypertrophy +- RV failure) •  Pneumonia •  Acute Respiratory Failure •  V/Q mismatch •  Emphysema: increase ventilation of poorly perfused lung units (high V/Q ratio) increased physiological dead space. *-the area is getting destroyed so blood flow will not be sent there with vasoconstriction. You are ventilating areas without blood flow, this is why pulmonary hypertension comes later in the disease •  Chronic bronchitis: perfusion of under-ventilated areas, low V/ Q ration and subsequent physiological shunt. *mucus pus in alveolar space, what is happening to your ventilation and perfusion. You are having areas poorly ventilated but still perfusing. That is what we call a shunt like hypoxia.

Answer 14

***interstitial lung disease also pneumonia, CHF

Answer 15

Fine crackles - altered by body position change but remains unaltered by coughing - it is not transmitted to mouth - produced by sudden inspiratory opening of small airways which were held closed during a previous expiration - *interstitial lung disease Coarse crackles - it is altered by coughing but not by body position changes - it can be transmitted to mouth - produced by gas passing through airways which undergo intermittent opening and closing.

Answer 16

- Pleural effusion 1. Breath sounds -decreased 2. Percussion -dull 3. Fremitus - decrease 4. Tracheal deviation: either none or away from side of lesion - Atelectasis 1. Breath sounds - decreased 2. Percussion -dull 3. Fremitus - decrease 4. Tracheal deviation -toward side of lesion - Simple pneumothorax 1. Breath sounds - decreased 2. Percussion -hyper-resonant 3. Fremitus - decrease 4. Tracheal deviation - none - Tension pneumothorax 1. Breath sounds - decreased 2. Percussion - hyper-resonant 3. Fremitus - decrease 4. Tracheal deviation - away from side of lesion - Consolidation (lobar pneumonia, pulmonary edema) 1. **Breath sounds - bronchial breath sounds, late inspiratory crackles, - egophony: Eee > Aaa change, associated with pleural effusion, - bronchophony: 99 if heard with increased clarity and distinction, - whispered pectoriloquy: whispered sounds heard clearly and distinctly 2. Percussion - dull 3. Fremitus - increase 4. Tracheal deviation - none

Answer 17

I said low O2 delivery, low mixed venous oxygen (MVO2) content- this is true and I may have said the tissues take more O2 etc. but to clarify- LOW O2 DELIVERY results in an INCREASE IN O2 EXTRACTION not in the use or consumption of oxygen, which reflects the metabolic rate of the tissue. The removal of an increased fraction of the O2 from the blood will result in LOW MVO2. To summarize, there are two main concepts linked to the idea of O2 content in mixed venous blood (MVO2). The first concept is related to oxygen delivery. ANY decrease in O2 delivery to the tissue will increase the extraction of oxygen from the blood (and by doing so, will decrease MVO2). The tissue will extract more oxygen from the blood in order to meet its metabolic needs (i.e. its rate of oxygen utilization)- so in fact, the RATE of O2 USE does not change, but % of O2 removed from the blood per 100 ml WILL INCREASE because less O2 is coming in. Thus, if you RESTORE O2 delivery, O2 extraction rate will return to baseline- but the use of O2 by the tissue- its metabolic rate, remains the same. We can make up some math for this: Let's say I NEED 32 oz. of coffee a day- and 64 oz. is regularly delivered- so I routinely take 50% of all the coffee coming to me. Well, one day, someone takes some of my coffee (grrrr! probably Dr. Foty)- and only 48 oz. gets to me- well, I still need my 32 oz- but if I take my regular 50%- I won't get what I need- so I take 75% this time. My needs haven't changed- but I need to increase my "extraction" of coffee-then, if the next day, the whole 64 oz. comes- I will go back to my 50%. So my coffee consumption does not change- only the fraction that I remove from the pot. I hope that makes sense. To problem solve for things that change MVO2 in this way, you want to think about what would be the causes of low oxygen delivery - think about the equation: DO2 (delivery) = Cardiac Output X O2 content of the blood (CaO2). As we have discussed, CaO2 is dependent on the the Hgb, O2 SAT and PaO2. So decreased CO, Hgb, O2 SAT and PaO2 will all result in a decrease in MVO2. The other main concept linked to MVO2 is oxygen consumption by the peripheral tissue (this is O2 USAGE- not to be confused with EXTRACTION)- so anything that increases (e.g. fever, exercise) or decreases (e.g.cyanide, hypothermia) tissue oxygen consumption (that is the USE of O2) will ALSO change the mixed venous O2- in this case, an increase in tissue O2 USE (i.e. metabolic rate) will decrease MVO2, while a decrease in tissue O2 use will increase MVO2. (so that is like, I am getting my 64 oz. delivered, but I decide to drink 40 oz today!)

Answer 18

FA: Autosomal RECESSIVE defect in CFTR gene on chromosome 7; commonly a deletion of Phe508. Most common lethal genetic disease in Caucasian population. __________________________ Patho: CFTR encodes an ATP-gated Cl− channel that secretes Cl− in lungs and GI tract, and reabsorbs Cl− in sweat glands. Most common mutation > misfolded protein > protein retained in RER and not transported to cell membrane, causing reduced Cl− (and H2O) secretion; increased intracellular Cl− results in compensatory increased Na+ reabsorption via epithelial Na+ channels > increased H2O reabsorption > abnormally thick mucus secreted into lungs and GI tract. increased Na+ reabsorption also causes more negative transepithelial potential difference. ___________________________ Diagnosis: Increased Cl− concentration (> 60 mEq/L) in sweat is diagnostic. Can present with contraction alkalosis and hypokalemia (ECF effects analogous to a patient taking a loop diuretic) because of ECF H2O/Na+ losses and concomitant renal K+/H+ wasting. Increased immunoreactive trypsinogen (newborn screening). __________________ Complications: 1. Recurrent pulmonary infections (eg, S aureus [early infancy], P aeruginosa [adolescence]), chronic bronchitis and bronchiectasis > reticulonodular pattern on CXR, opaciication of sinuses. 2. Pancreatic insuficiency, malabsorption with steatorrhea, fat-soluble vitamin deiciencies (A, D, E, K) leading to foul smelling feces 3. biliary cirrhosis, liver disease. Meconium ileus in newborns. Infertility in men (absence of vas deferens, spermatogenesis may be unaffected) and subfertility in women (amenorrhea, abnormally thick cervical mucus). Nasal polyps, clubbing of nails. _____________ Treatment: Multifactorial: chest physiotherapy, albuterol, aerosolized dornase alfa (DNAse), and hypertonic saline facilitate mucus clearance. Azithromycin used as anti-inlammatory agent. Ibuprofen slows disease progression. Pancreatic enzymes for insuficiency. Sweat glands With the lungs, CFTCR is secreting chloride. What follows the chloride? Sodium. What follows sodium? Water. That is why the mucus is so sticky and thick because no water. Lung epithelial cells - CFTCR (cystic fibrosis transmembrane conductance regulator) The two ions are chloride and sodium but CFTCR is a chloride channel. Has a big role in the sweat glands. when sweat is secreted there is a lot of sodium and chloride in the lumen. As it goes through the lumen, there are channels along the way to reabsorb. CFTCR are the chloride channels here, chloride will be reabsorbed into the body (as sodium does through their channels, balanced). So there are few sodium and chloride ions remaining in sweat, when we sweat alot the sweat becomes actually saltier because we its faster. CF - no problem with sodium channel, chloride channels are not open so it can’t leave and keeps going towards the skin, Negative and positive want to stay together. Sodium is pulled by the chloride so alot more is in the sweat now. Salty skin is a symptom of CF.

Answer 19

Obstructive - In obstructive disease, flow is reduced during expiration (scooped out curve) resulting in air trapping and an increase in RV. -due to premature closing of those airways, loop shifts to the left. Inspiration is relatively normal Restrictive - In restrictive disease, flow is normal during expiration resulting in a normal or increased slope in the expiratory phase. The problem here is the lung is stiff and all lung volumes are reduced. Loop shifts to right and is smaller everywhere Fixed Obstruction - Fixed obstruction somewhere in large airways affecting flow in both the inspiratory and expiratory phases -flat inspiration and expiration, looks like a rectangle sort of Variable extrathoracic - Obstruction is extrathoracic and only occurs in inspiration when pressure in trachea becomes negative relative to atmospheric pressure Variable intrathoracic - Obstruction is intrathoracic and only occurs during expiration when pressure in lung becomes greater than internal large airway pressure

Answer 20

Flail chest is a life-threatening condition that occurs when the rib cage is broken in several places due to trauma and becomes detached from the rest of the chest wall. Classic cause of paradoxical chest movement. Inspiration - broken chest wall goes in due to negative pressure Expiration

Answer 21

F. carbon monoxide Cyanide effectively and rapidly halts mitochondrial oxidative phosphorylation by binding to the ferric iron (Fe3+) of cytochrome oxidase a3. Affected cells can't use oxygen for aerobic respiration, resulting in high anion-gap lactic acidosis - and as we have already discussed, one of the clues will be a RISE in the mixed venous oxygen content. While cyanide does bind to the ferrous form (Fe2+) of iron found in oxyhemoglobin - it DOES NOT bind to the Fe2+ in oxyhemoglobin very well; it prefers Fe3+ (ferric form; methemoglobin)- which circulates in the blood in small amounts (range is 0-3% of total hemoglobin)- and therefore WHEN cyanohemoglobin IS measured in the blood, it really reflects the binding of cyanide to the ferric form of iron in methemoglobin primarily. For this reason, you would not expect cyanide to cause the O2 sat to drop in such a large way- Step 1 wants you to know that the problem with cyanide is in the periphery with the ability of the tissues to USE the oxygen that is delivered. I also attached a cyanide cartoon- it is a "sketchy".

Answer 22

Anion gap = (Na+) - (Cl- + HCO3-) >12 mEq/L is elevated anion gap 8-12 is normal anion gap MUDPILES - metabolic acidosis with elevated anion gap - methanol (formic acid) - uremia - diabetic ketoacidosis - propylene glycol - iron tablets or INH - lactic acidosis - ethylene glycol - salicylates ``` Normal anion gap metabolic acidosis HARDASS Hyperalimentation (Addison disease - primary adrenal insufficiency/hypocortisolism) Renal tubular acidosis Diarrhea Acetazolamide Spironolactone Saline infusion ```

Answer 23

Rotation • The medial aspect of each clavicle should be equidistant from the spinous processes • The spinous processes should also be in vertically orientated against the vertebral bodies. should be visible projected within the chest, it’s PA. Inspiration • 5-6 anterior ribs, the lung apices, both costophrenic angles and lateral rib edges Projection • AP vs PA film • Tip- if there is no label, then assume it’s a PA. Also, if the scapulae are not • Exposure • Left hemidiaphragm visible to the spine and vertebrae visible behind heart

Answer 24

PRESENTATION Findings: wheezing, crackles, cyanosis (hypoxemia due to shunting), dyspnea, CO2 retention, 2° polycythemia. PATHOLOGY Hypertrophy and hyperplasia of mucus-secreting glands in bronchi > Reid index (thickness of mucosal gland layer to thickness of wall between epithelium and cartilage) > 50%. OTHER Diagnostic criteria: productive cough for > 3 months in a year for > 2 consecutive years. [Class notes]: Elimination: Difficulty in clearing secretions because of poor ciliary function, distal airway occlusion and ineffective cough secondary to respiratory muscle weakness and reduced peak expiratory flow Production: Airflow obstruction: increased mucus hypersecretion causes luminal occlusion,epithelial layer thickening encroaches on the airway lumen and increased mucus alters airway surface tension, thereby predisposing it to expiratory collapse Inflammation: Inhaled cig smoke and noxious stimuli •  Increase neutrophils in airway lumen •  Macrophages in airway lumen, wall and parenchyma •  CD8 lymphocytes in airway wall and parenchyma (as opposed to CD4 in asthma)

Answer 25

``` Findings: cough, wheezing, tachypnea, dyspnea, hypoxemia, decreased inspiratory/ expiratory ratio, pulsus paradoxus, mucus plugging. Triggers: viral URIs, allergens, stress. Diagnosis supported by spirometry and methacholine challenge ``` Bronchial hyperresponsiveness > reversible bronchoconstriction. Smooth muscle hypertrophy and hyperplasia, Curschmann spirals (shed epithelium forms whorled mucous plugs), and *Charcot-Leyden crystals (eosinophilic, hexagonal, double-pointed, needle-like crystals formed from breakdown of eosinophils in sputum ``` Aspirin-induced asthma: COX inhibition > leukotriene overproduction > airway constriction. Associated with nasal polyps ```

Answer 26

Bronchiectasis Findings: purulent sputum, recurrent infections, hemoptysis, digital clubbing. Chronic necrotizing infection of bronchi > permanently dilated airways. ``` Associated with bronchial obstruction, poor ciliary motility (eg, smoking, Kartagener syndrome), cystic fibrosis, allergic bronchopulmonary aspergillosis. ``` ``` [class notes] •  occurs in the context of chronic airway infection and inflammation •  mild to moderate airflow obstruction •  Small airways in bronchiectasis are obstructed from an inflammatory infiltrate in the wall ``` Etiology (think infection) •  Congenital or hereditary conditions: cystic fibrosis, intralobar sequestration of the lung, immunodeficiency states, primary ciliary dyskinesia and kartagener syndrome •  Bronchial obstruction due to tumor, foreign bodies, and mucus impaction •  Other conditions such as rheumatoid arthritis, systemic lupus erythematous, inflammatory bowel disease, and post- transplantation (chronic lung rejection and chronic graft- versus-host disease after bone marrow transplantation)

Answer 27

Intermittent: symptoms <2 days/wk -exacerbations requiring oral systemic corticosteroids 0-1 times/yr Step 1 treatment- consider low dose inhaled corticosteroids, As needed short acting beta agonists Mild: symptoms >2 days/wk but not daily, -exacerbations requiring oral systemic corticosteroids 2 times/yr Step 2 treatment - low dose inhaled corticosteroids, leukotriene receptor antagonist, low dose theophylline, As needed short acting beta agonists Moderate: symptoms daily -exacerbations requiring oral systemic corticosteroids 2 times/yr Step 3 treatment: Low dose ICS/LABA (long acting beta2 agonists) Severe: symptoms throughout the day -exacerbations requiring oral systemic corticosteroids 2 times/yr Step 4 or 5 treatment: normal dose of ICS/LABA, add on treatment of tiotropium, anti-IgE, anti IL5, bronchial thermoplasty *same time frames for usage of short acting beta agonists

Answer 28

Resistive work: energy needed to move air through the conducting airways to the alveoli. Elastic work: energy needed to expand the lungs against their own recoil and the recoil of their surroundings (e.g. chest wall, abdomen, etc.)

Answer 29

•  Autosomal recessive syndrome with variable penetrance •  1 in 15,000 to 40,000 births, poorly functioning cilia •  There is an absence or shortening of the dynein arms •  Kartagener syndrome: bronchiectasis, sinusitus, and situs inversus or partial lateralizing abnormality. Therapy •  Airway clearance •  Antibiotics •  Antinflammatory •  Preventing exacerbations

Answer 30

Samter’s triad (Aspirin Exacerbated Respiratory Disease (AERD), also known as Samter's Triad or Aspirin Sensitive Asthma) 1. Asthma, 2. Chronic rhinosinusitis with polyposis, 3. aspirin/NSAID sensitivity)

Answer 31

Upper Airway Cough Syndrome • Post nasal drip due to various etiologies • Secretions in airway stimulate cough receptors in the laryngeal mucosa • Common reason for chronic cough • Tx: treat post nasal drip

Answer 32

Paradoxical Vocal Fold Motion/Vocal Cord Dysfunction (VCD) *important to think for treatment resistant asthma • Mistimed vocal fold closure creates difficulty breathing – Vocal folds are held in a paramedian position through inspiration and expiration • Misdiagnosed as asthma • Psychogenic component theorized • Post nasal drip, inhaled or aspirated irritants, allergies or GERD may cause laryngeal hyperresponsivenss • TX- Treat underlying causes, reassurance, breathing instruction

Answer 33

Vocal Fold Paralysis • Unilateral- Usually asymptomatic • Airway obstruction can be measured during both quiet and active breathing • The action of inspiratory airflow producing a Bernoulli effect on the flaccid vocal fold (because they are now closer together, increases chance of the two collapsing on each other) • Inappropriate reinnervation of the paralyzed vocal fold with active signals for adduction during inspiration • Tx- Surgery or botulinum toxin injection Bilateral- Very symptomatic on exertion, weak, breathy voice • Most commonly due to surgery in the anterior compartment of the neck (Thyroid Surgery) • Injury to recurrent laryngeal nerves • Loss of vocal cord abduction during inspiration • Loss of adduction for phonation • Tx- Surgery, botulinum injection, tracheotomy

Answer 34

Glottic Stenosis Scarring of the larynx • Usually posterior (PGS) • Most common event associated with onset is prolonged intubation (foreign body leading to excessive scarring) • As the endotracheal tube rubs against the mucosa of the posterior larynx, the mucosa is eroded and inflammation develops • Clinically and endoscopically it can be difficult to distinguish from bilateral vocal fold paralysis • PGS usually have a normal voice because vocal fold adduction is maintained

Answer 35

Subglottis is surrounded by a firm cartilaginous structure and the mucosa lies over the surface with only a normal submucosa for support of the epithelium • Prone to injury from pressure or inflammation • Injury to the mucosa by any one of the prior processes can lead to exposure of the perichondrium, which then responds with inflammation and scar tissue formation • The scar tissue impedes airflow and mucus clearance Caused by prolonged intubation, surgery, and autoimmune disease (Granulomatosis with Polyangitis) • Tx- Surgical

Answer 36

Exposure to known offending antigen - OR 38! Symptoms 4-8 hours after exposure OR: 7 Positive precipitating antibodies Inspiratory Crackles Recurrent episodes of symptoms weight Loss Note: all six variables positive 98% chance of having HP; w/o weight loss 97% chance

Answer 37

Caused by parainluenza viruses (paramyxovirus). Virus membrane contains hemagglutinin (binds sialic acid and promotes viral entry) and neuraminidase (promotes progeny virion release) antigens. Results in a “seal-like” barking cough and inspiratory stridor. Narrowing of upper trachea and subglottis leads to characteristic steeple sign on x-ray A . Severe croup can result in pulsus paradoxus 2° to upper airway obstruction. Respiratory illness characterized by a hoarse voice, dry ‘barking’ cough, inspiratory stridor and a variable amount of respiratory distress resulting from upper airway obstruction.

Answer 38

he has consolidation renal failure lactic acidosis with hypoxia and huge A-a gradient. Consolidation with right lower lobe Severe Community Pneumonia with hypoxemia, leucocytosis, left shift, gap metabolic acidosis due to lactic acidosis. • Blood and sputum culture, sensitivity was obtained.

Answer 39

• Positive pressure ventilation results in – End-inspiratory alveolar overdistention (volutrauma) – End-expiratory alveolar derecruitment (atelectrauma) – Biochemical injury and inflammation (biotrauma) Volutrauma • Large tidal volumes lead to increased wall stress (“stretch”) – Gross physical disruption of lung tissue – Activation of stretch-responsive inflammatory pathways in lung epithelial cells. – Increased parenchymal inflammation, atelectasis, hypoxia and cytokine production. Atelectrauma • Cyclic closing and reopening of alveoli with each tidal breath • Alveolar shear-stress related injury – Biochemical injury and inflammation (biotrauma) results from this mechanical stress Lung Protection strategy – Low tidal volumes (6cc/kg PBV) – Optimal PEEP – Recruitment maneuvers – Prone positioning

Answer 40

Rales = discontinuous sound, crackles, associated with alveoli, the most distal portion of airway -usually due to fluid accumulation - pneumonia, pulmonary edema, can also be caused by atelectasis from PE Rhonchi = wheezing, occurs in large airways, bronchus, continuous sound -inflammatory in nature - asthma, chronic bronchitis, wheezing, constriction - or can be due to secretions Rales in the tails, rhonchi in the bronchi!

Answer 41

Vesicular - normal sound on most of lung - soft, low pitch - inspiration longer than expiration - no gap between phases Bronchial -abnormal in majority of lung that is far from main airways -loud tubular quality -high pitched -inspiratory and expiratory phase equal -definite gap between phases HEARD in - Consolidation, lobar Collapse with patent bronchus, lung Cavity

Answer 42

1. increased tactile fremitus 2. Bronchophony 3. Aegophony (BEE heard as BAY) 4. Whispering pectoriloquy

Answer 43

Continuous and musical quality Expiratory usually indicates narrowing of airways EITHER due to bronchospasm OR secretions in small airways low pitch or high pitch High pitch polyphonic or monophonic during inspiration the elasticity of the airways will cause them to dilate which will allow air to flow around the obstruction. As the airways contract during exhalation, airflow will increase causing the high pitched sounds associated with wheezing

Answer 44

Interrupted and non musical inspiratory usually peripheral airway collapse on expiration due to either interstitial fibrosis or secretions/fluid During inspiration, rapid air entry abruptly opens these collapsed smaller airways and alveoli producing crackling noise. Can be 1. early inspiratory in small airways disease like broncholitis 2. mid inspiratory in pulmonary edema 3. Late inspiratory in pulmonary fibrosis, pulmonary edema, COPD, resolving pneumonia, lung abscess, tuberculous lung cavities 4. biphasic in bronchiectasis Fine crackles - broncholitis, pulmonary edema, pulmonary fibrosis Coarse: COPD, resolving pneumonia, lung absess, tuberculous lung cavities, bronchiectasis

Answer 45

you must perform a brief inspiratory hold maneuver, if the rub continues during the maneuver it is most likely a pericardial rub.

Answer 46

Leading cause of cancer death. Presentation: cough, hemoptysis, bronchial obstruction, wheezing, pneumonic “coin” lesion (solitary nodule) on CXR or non calcified nodule on CT. - Sites of metastases from lung cancer: adrenals, brain, bone (pathologic fracture), liver (jaundice, hepatomegaly). - In the lung, metastases (usually multiple lesions) are more common than 1° neoplasms. Most often from breast, colon, prostate, and bladder cancer. SPHERE of complications: Superior vena cava syndrome: obstruction of SVC leads to distended head and neck veins with edema and blue discoloration of arms and face (SVC syndrome) Pancoast tumor: a tumor of the pulmonary apex. It is a type of lung cancer defined primarily by its location situated at the top end of either the right or left lung. It typically spreads to nearby tissues such as the ribs and vertebrae. Horner syndrome Endocrine (paraneoplastic) Recurrent laryngeal nerve compression (hoarseness) Effusions (pleural or pericardial) Risk factors include smoking, secondhand smoke, radon, asbestos, family history. Squamous and Small cell carcinomas are Sentral (central) and often caused by Smoking. Small cell usually not amenable to surgical resection (chemotherapy and radiation) Non-small cell: usually amenable to surgical resection, usually doesn’t respond well to chemo)

Answer 47

``` [Small cell carcinoma] Characteristic histology: 1. poorly differentiated small cells from neuroendocrine cells [chromogranin positive] 2. Neuron-specific enolase positive ``` Association: male smokers Location: central Comment: rapid growth and early metastasis may produce endocrine (ADH or ACTH) or nervous system: (Labert-Eaton myasthenic syndrome: antibodies against presynaptic Ca2+ channels Paraneoplastic myelitis, encephalitis, subacute cerebellar degeneration Amplification of myc oncogenes common. Managed with chemotherapy +/- radiation

Answer 48

[Adenocarcinoma] Characteristic histology: glands or mucin production (stains positive) Association: nonsmokers and female smokers (most common lung cancer overall excluding metastasis) Location: Peripheral Bronchoalveolar: grows along alveolar septa> apparent “thickening” of alveolar walls. Tall columnar cells containing mucus *may present as pneumonia like consolidation on imaging but excellent prognosis Comment: activating mutations include KRAS, EGFR, and ALK. Associated with hypertrophic osteoarthropathy - clubbing Bronchial carcinoid and bronchioalveolar cell have less association with smoking

Answer 49

Squamous cell carcinoma Characteristic histology: *keratin pearls OR intercellular bridges Association: male smokers Location: central Comment: Hilar mass arising from bronchus: 3C’s cavitation, cigarettes, hypercalcemia from PTHrP

Answer 50

Characteristic histology: pleomorphic giant cells Association: smoking Location: central or peripheral Comment : highly anaplastic undifferentiated tumor, POOR prognosis, less responsive to chemotherapy, removed surgically. Strong association with smoking .

Answer 51

Excellent prognosis, metastasis rare SYmptoms due to mass effect or carcinoid syndrome: flushing, diarrhea, wheezing Nests of neuroendocrine cells, chromogranin A positive like small cell carcinoma. Not related to smoking central or peripheral, classically presents as a polyp-like mass in the bronchus. Its a low grade malignancy!

Answer 52

Neonates (<4 wk) Group B streptococci E coli ``` Children (4 wk - 18 years) -Viruses (RSV) -Mycoplasma -C trachomatis (infant s –3 y r) -C pneumoniae (scho ol- a ged children) S pneumoniae Runts May Cough Chunky Sputum ``` ``` Adults (18-40) Mycoplasma C pneumoniae S pneumoniae Viruses (eg, influenza ``` ``` Adults (40-65) S pneumoniae *H inluenzae *Anaerobes Viruses Mycoplasma ``` ``` Elderly (65+) S pneumonia Influenza virus Anaerobes H influenza Gram negative rods ```

Answer 53

coin lesion especially in younger patients (<40) 1. Granuloma- often due to TB or fungus * *If Midwest - Histoplasma 2. bronchial hamartoma - benign tumor composed of lung tissue and cartilage often calcified on lung

Answer 54

Look at old xrays

Answer 55

TNM staging system (Stage = Spread): T = Tumor size/invasiveness - obstruction of SVC leads to distended head and neck veins with edema and blue discoloration of arms and face (SVC syndrome) -involvement of recurrent laryngal (hoarseness or phrenic ( diaphragmatic paralysis nerve) -involvement of the SNS chain (Horners) and brachial plexus (should pain and hand weakness is seen with pancoast tumors! N = Node involvement -hilar, mediastinal M = Metastases Each TNM factor has independent prognostic value; N and M factors are often most important. **adrenal gland is high yield

Answer 56

``` [exudate] Cellular (cloudy) elevated protein (> 2.9 g/dL) elevated LDH (vs serum) Due to: Lymphatic obstruction (chylous) Inlammation/infection Malignancy ``` [transudate) Hypocellular (clear) low protein (< 2.5 g/dL) low LDH (vs serum) Due to: increased hydrostatic pressure (eg, HF, Na+ retention) reduced oncotic pressure (eg, cirrhosis, nephrotic syndrome Light Criteria Diagnostic analysis comparing serum and pleural fluid protein and LDH levels. Pleural effusion is exudative if ≥ 1 of the following criteria is met: Pleural effusion protein/serum protein ratio > 0.5 Pleural effusion LDH/serum LDH ratio > 0.6 Pleural effusion LDH > 2⁄3 of the upper limit of normal for serum LDH

Answer 57

Restricted lung expansion causes reduced lung volumes (reduced FVC and TLC). PFTs: FEV1/FVC ratio ≥ 80%. Patient presents with short, shallow breaths. Ty p e s : 1. Poor breathing mechanics (extrapulmonary, peripheral hypoventilation, normal A-a gradient): -Poor muscular effort—polio, myasthenia gravis, Guillain-Barré syndrome -Poor structural apparatus—scoliosis, morbid obesity 2. Interstitial lung diseases (pulmonary reduced diffusing capacity, increased A-a gradient): -Pneumoconioses (eg, coal workers’ pneumoconiosis, silicosis, asbestosis) -Sarcoidosis: bilateral hilar lymphadenopathy, noncaseating granuloma; increased ACE and Ca2+ -Idiopathic pulmonary fibrosis (repeated cycles of lung injury and wound healing with increased collagen deposition, “honeycomb” lung appearance and digital clubbing) • Repeated cycles of epithelial activation/injury by some unidentified agent followed by abnormal epithelial repair at the site of injury • Leads to excessive fibroblastic proliferation resulting in characteristic fibroblastic foci seen on lung biopsy • Areas of both early injury/repair and late collagen deposition lead to characteristic “temporal heterogeneity” Radiographic feature: basal-predominant reticular abnormality with volume loss. Granulomatosis with polyangiitis: inflammation of multiple blood vessels or lymph vessels (Wegener) Pulmonary Langerhans cell histiocytosis (eosinophilic granuloma) Drug induced pulmonary fibrosis: (bleomycin, busulfan, amiodarone, methotrexate) Hypersensitivity pneumonitis—mixed type III/IV hypersensitivity reaction to environmental antigen. Causes dyspnea, cough, chest tightness, headache. Often seen in farmers and those exposed to birds. Reversible in early stages if stimulus is avoided. • Also called extrinsic allergic alveolitis • Results from repeated inhalation of finely dispersed antigens • Antigens encompass a wide variety of organic particles • Sources include mammalian and avian proteins, thermophilic bacteria, fungi, certain small MW chemical compounds • Acute form results from intermittent and intense exposure • Symptoms occur 4-8 hrs. after exposure and characterized by fever, chills, malaise, dyspnea and cough • Subacute and chronic forms result from continual, low-level exposure, usually in the domestic environment • Onset insidious; main symptoms are dyspnea and fatigue • Unrecognized and untreated subacute form may progress to chronic form with irreversible lung changes • Exam usually shows tachypnea and crackles in all forms • Acute form shows diffuse ground-glass appearance or air-space consolidation • In subacute form CXR shows fine nodular or reticulonodular pattern • Chronic form shows predominantly a reticular pattern • Distribution involves mainly the upper two-thirds of the lungs

Answer 58

Pulmonary complication associated with smoke and fire. Caused by heat, particulates ( chemical tracheobronchitis, edema, pneumonia, ARDS. Many patients present 2° to burns, CO inhalation, cyanide poisoning, or arsenic poisoning. Bronchoscopy shows severe edema, congestion of bronchus, and soot deposition ( A , 18 hours after inhalation injury; B , resolution at 11 days after injury).

Answer 59

Coal workers’ pneumoconiosis, silicosis, and asbestosis > increased risk of cor pulmonale, cancer, and Caplan syndrome (rheumatoid arthritis and pneumoconioses with intrapulmonary nodules). Asbestos is from the roof (was common in insulation), but affects the base (lower lobes). Silica and coal are from the base (earth), but affect the roof (upper lobes).

Answer 60

Associated with shipbuilding, rooing, plumbing. “Ivory white,” calcified, supradiaphragmatic and pleural plaques are pathognomonic of asbestosis. Risk of bronchogenic carcinoma > risk of mesothelioma. Affects lower lobes. Asbestos (ferruginous) bodies are golden-brown fusiform rods resembling dumbbells, found in alveolar sputum sample, visualized using Prussian blue stain, often obtained by bronchoalveolar lavage. increased risk of pleural effusions (consistent with increased risk of lung cancer)

Answer 61

Associated with exposure to beryllium in aerospace and manufacturing industries. Granulomatous (noncaseating) on histology and therefore occasionally responsive to steroids. Affects upper lobes

Answer 62

Prolonged coal dust exposure > macrophages laden with carbon > inflammation and fibrosis. Also known as black lung disease. Affects upper lobes. Anthracosis—asymptomatic condition found in many urban dwellers exposed to sooty air.

Answer 63

*most common worldwide Simple vs complicated silicosis Simple: mildest, earliest form of disease -asymptomatic or have chronic cough CXR shows upper zone distribution of small rounded opacities less than 10 mm in diameter • Symptoms do not correlate with CXR findings • PFT’s initially normal but TLC decreases as the number/density of opacities increase • Tuberculosis incidence increased by 2-30 fold Associated with foundries, sandblasting, mines. Macrophages respond to silica and release fibrogenic factors, leading to fibrosis. It is thought that silica may disrupt phagolysosomes and impair macrophages, increasing susceptibility to *****TB. Affects upper lobes Eggshell calcification in hilar lymph nodes on CXR - nicely surrounded Complicated Silicosis • AKA: Progressive Massive Fibrosis • Occurs when smaller opacities coalesce • Symptoms range from minimal to severe dyspnea • CXR shows confluent nodules > 10mm • Nodules become confluent peripherally and migrate centrally • PFT’s show progressive deterioration • Progression in absence of further exposure

Answer 64

Malignancy of the pleura associated with asbestosis. May result in hemorrhagic pleural effusion (exudative), pleural thickening. Psammoma bodies seen on histology. Cytokeratin and calretinin ⊕ in almost all mesotheliomas, ⊝ in most carcinomas. Smoking not a risk factor.

Answer 65

Diagnosis of exclusion characterized by respiratory failure within 1 week of alveolar insult, bilateral lung opacities, decreased PaO2/FiO2 < 300 (hypoxemia due to increased intrapulmonary shunting and diffusion abnormalities), no evidence of HF/fluid overload. Many causes and associations, including sepsis, *pancreatitis, pneumonia, aspiration, trauma, shock. Endothelial damage leads to increased alveolar capillary permeability > protein-rich leakage into alveoli > diffuse alveolar damage and noncardiogenic pulmonary edema (normal PCWP) Results in formation of intra- alveolar hyaline membranes Initial damage due to release of neutrophilic substances toxic to alveolar wall and pulmonary capillary endothelial cells, activation of coagulation cascade, and oxygen-derived free radicals. Management: mechanical ventilation with low tidal volumes, address underlying cause.

Answer 66

Sleep apnea: Repeated cessation of breathing > 10 seconds during sleep > disrupted sleep leads to increased daytime somnolence. Diagnosis confirmed by sleep study. Normal Pao2 during the day. Nocturnal hypoxia > systemic/pulmonary hypertension, arrhythmias (atrial fibrillation/flutter), sudden death. Hypoxia > increased EPO release > increased erythropoiesis. Obstructive: Respiratory effort against airway obstruction. Associated with obesity, loud snoring. Caused by excess parapharyngeal tissue in adults, adenotonsillar hypertrophy in children. Treatment: weight loss, CPAP, surgery. Central sleep apnea: No respiratory effort due to CNS injury/toxicity, HF, opioids. “Central sleep apnea is a disorder in which your breathing repeatedly stops and starts during sleep. Central sleep apnea occurs because your brain doesn't send proper signals to the muscles that control your breathing. ... Central sleep apnea is less common than obstructive sleep apnea” May be associated with Cheyne-Stokes respiration. Treat with positive airway pressure. Obesity hypoventilation syndrome: Obesity (BMI ≥ 30 kg/m2) > hypoventilation > increased PaCO2 during waking hours (retention); decreased PaO2 and increased PaCO2 during sleep. Also known as Pickwickian syndrome.

Answer 67

1. Idiopathic pulmonary fibrosis (usual interstitial pneumonia) 2. Hypersensitivity pneumonitis (inspiratory) 3. Asbestosis (basal crackles) 4. acute pulmonary embolism

Answer 68

Characterized by immune-mediated, widespread noncaseating granulomas , elevated serum ACE levels, and elevated CD4+/CD8+ ratio in bronchoalveolar lavage fluid. More common in African-American females. Often asymptomatic except for enlarged lymph nodes. Findings on CXR of bilateral adenopathy and coarse reticular opacities; CT of the chest better demonstrates the extensive hilar and mediastinal adenopathy - bilateral hilar is most common C . Associated with *restrictive lung disease (interstitial fibrosis), erythema nodosum, lupus pernio (skin lesions on face resembling lupus), Bell palsy, epithelioid granulomas containing microscopic Schaumann and asteroid bodies, uveitis, hypercalcemia (due to q 1α-hydroxylase–mediated vitamin D activation in macrophages). Treatment: steroids (if symptomatic). Lecture: extrapulmonary sarcoidosis • Ophthalmic granulomatosis • Peripheral adenopathy • Cutaneous rash • Central nervous system involvement • Cardiac arrhythmias • Hepatitis • *Hypercalcemia: one of the first symptoms

Answer 69

c-ANCA associated vasculitis which can cause cavitary lesions in the lungs. most patients are oldr males with chronic sinusitis, hemoptysis, and renal involvement. THese patients may have low grade fever and lung cultures would be negative. Granulomatosis with polyangiitis (GPA), also known as Wegener's granulomatosis (WG), is a systemic disorder that involves both granulomatosis and polyangiitis. It is a form of vasculitis (inflammation of blood vessels) that affects small- and medium-size vessels in many organs. Damage to the lungs and kidneys can be fatal. Treatment requires long-term immunosuppression.[1] Granulomatosis with polyangiitis is part of a larger group of vasculitic syndromes called systemic vasculitides or necrotizing vasculopathies, all of which feature an autoimmune attack by an abnormal type of circulating antibody termed ANCAs (antineutrophil cytoplasmic antibodies) against small and medium-size blood vessels. Apart from GPA, this category includes eosinophilic granulomatosis with polyangiitis (EGPA) and microscopic polyangiitis.[1] Although GPA affects small- and medium-size vessels,[2] it is formally classified as one of the small vessel vasculitides in the Chapel Hill system Can cause subglottic and tracheal cervical stenosis

Answer 70

1. Antithrombin deficiency: Inherited deiciency of antithrombin: has no direct effect on the PT, PTT, or thrombin time but diminishes the increase in PTT following heparin administration. Can also be acquired: renal failure/nephrotic syndrome > antithrombin loss in urine > reduced inhibition of factors IIa and Xa. 2. Factor V Leiden Production of mutant factor V (G p A DNA point mutation > Arg506Gln mutation near the cleavage site) that is resistant to degradation by activated protein C. Most common cause of inherited hypercoagulability in Caucasians. Complications include DVT, cerebral vein thromboses, recurrent pregnancy loss. 3. Protein C or S Reduced ability to inactivate factors Va and VIIIa. Increased risk of thrombotic skin necrosis with hemorrhage after administration of warfarin. If this occurs, think protein C deiciency. Together, protein C Cancels, and protein S Stops, coagulation. 4. Prothrombin gene mutation: Mutation in 3′ untranslated region > increased production of prothrombin > increased plasma levels and venous clots.

Answer 71

Blood clot within a deep vein > swelling, redness , warmth, pain. Predisposed by Virchow triad (SHE): Stasis (eg, post-op, long drive/light) Hypercoagulability (eg, defect in coagulation cascade proteins, such as factor V Leiden) Endothelial damage (exposed collagen triggers clotting cascade) d-dimer lab test used clinically to rule out DVT (high sensitivity, low speciicity). Most pulmonary emboli arise from proximal deep veins of lower extremity. Use unfractionated heparin or low-molecular-weight heparins (eg, enoxaparin) for prophylaxis and acute management. Use oral anticoagulants (eg, warfarin, rivaroxaban) for treatment (long-term prevention). Imaging test of choice is compression ultrasound with Doppler.

Answer 72

Obstruction of sinus drainage into nasal cavity > inflammation and pain over affected area (typically maxillary sinuses, filled with fluid on the right in, which drain into the middle meatus, in adults). Most common acute cause is viral URI; may cause superimposed bacterial infection, most commonly 1. S pneumoniae, 2. H inluenzae, 3. M catarrhalis.

Answer 73

Arterial - form under high shear stress - endothelial cell is disrupted - thrombus is platelet rich - use anti-platelet drugs - “white clots” ``` Venous -form under low shear stress -endothelial cell is intact -fibrin-rich -use anti-coagulants for treatment “red clots” ```

Answer 74

Paget-Shroetter Syndrome: - spontaneous upper extremity thrombosis - compression at the thoracic outlet - #1 cause of SPONTaneous UE DVT May-Thurner syndrome -compression of the left common iliac vein by the right common iliac artery

Answer 75

Massive proximal DVT of the lower extremities Signs and symptoms include: - sudden severe leg pain with swelling - cyanosis - edema - various gangrene - arterial compromise

Answer 76

a marker of Th2 | eosinophil mediated inflammation

Answer 77

Parasympathetic nerve stimulation produces bronchoconstriction, mediated by M3 receptors. • M3 receptor activation also increases airway secretions

Answer 78

A cause of necrotizing inflammation to bronchioles and bronchi, causing bronchiectasis -hypersensitivity reaction to aspergillosis leading to chronic inflammatory damage. Usually seen in individuals with asthma or cystic fibrosis

Answer 79

Any: 1. bacterial pneumonia 2. TB 3. non-Hodgkin lymphoma <200 cells/uL: 1. Bacterial pneumonia w/ bacteremia 2. disseminated TB 3. Pneumocystis TB 4. Cryptococcus neoformans <100 cells/uL: 1. Staphylococcus 2. Pseudomonas 3. Kaposi sarcoma (pulm manifestations) 4. Toxoplasmosis 50-100 cells/uL: 1. Endemic fungi 2. Mycobacterium avium complex (MAC) 3. nonedemic fungi 4. CMV

Answer 80

(B) streptococcus pneumonia CD4 is high enough

Answer 81

B) prior vaccination via BCG PPD tells you nothing about the time course.

Answer 82

Sputum should assessed for other etiologies not Tb

Answer 83

``` •  Seen in bacterial pneumonia •  Four stages of inflammatory response: –  Congestion –  Red hepatization –  Gray hepatization –  Resolution •  (But might have residual fibrous thickening, adhesions, scarring) ```

Answer 84

G+, alpha hemolytic (surrounding zone is a green hue) -optochin sensitive, lancet shaped diplococci, bile soluble **Most Common Cause of Community acquired pneumonia ``` •  Sputum -- rust colored, lobar pneumonia MOPS; meningitis, otitis media, pneumonia, sinusitis #1 cause of all of these. •  Alveolar architecture preserved –  When minimal residual destruction •  If baseline compromised lung function -- can lead to decompensation •  20% of adults – normal flora –  Need clinical and infectious picture too ``` Some serotypes can cause empyema and bronchopleural fistula. Treatment: azithromycin, macrolides, ceftriaxone

Answer 85

Haemophilus Influenzae •  Most common cause of of bacterial acute COPD exacerbation •  A-F serotypes, pleomorphic G negative –  Vaccine is against b – most virulent form •  Capsulated forms •  Non-capsulated forms emerging more –  Incidence increasing, some non- typeable –  URI symptoms first – otitis media, sinusitis, bronchopneumonia •  Neonates, cancer patients, Immune compromised •  Pediatric Emergency – high mortality rate pre-vaccine

Answer 86

Moraxella catarrhalis •  Seen more in elderly, Gram negative diplococus •  2nd Most common Cause of bacterial COPD exacerbation •  Common cause of otitis media in children •  Another bronchopulmonary pathologic agent •  Perhaps 30% of humans are colonized upper respiratory tract early

Answer 87

Staphylococcus Aureus •  MSSA – in the community, but MRSA-CAP can be seen too –  Hospital acquired can be MRSA more •  Common cause of 2ndary bacterial pneumonia after virus/influenza •  Can lead to persistent anatomic complications abscess/empyema/cavitations •  IV Drug Users – seed the lung via bacteremia first •  Daptomycin inactivated by surfactant – so not great for PNA Vancomycin

Answer 88

Klebsiella Pneumoniae •  Most common cause of Gm negative bacterial pneumonia •  Debilitated, malnourished, alcoholics •  Thick, mucoid, blood tinged sputum –  Produces viscid capsular polysaccharide which makes it tough to expectorate •  Can form abscess 3A’s - alcoholics, abscesses, aspiration -Klebsiella is immotile -cavatary lesion on patients right lobe is tb like urease positive treat with ceftriaxone, cefotaxime

Answer 89

Legionella pneumophila •  Thin, pleomorphic, flagellated, Gram negative •  Artificial aquatic environments –  Water cooling and tubing systems •  Again, common in sicker people and smokers •  Rapid dx –  Legionella Urine Antigen (only tests for a subtype) –  Culture is gold standard though (pathogenic regardless of how much •  Can be fatal in up to 15% •  Variable radiographic appearnce –  Infiltrates or consolidation •  Need to identify since it’s outbreak associated •  Atypical –TX is  Fluorquinolone or macrolide visualized under silver stain - need cysteine and iron to be added to the agar. Pontiac fever - fever and malaise usually is self limited. Common in smokers and elderly men Blue print: atypical pneumonia patchy unilobed infiltrate (FA) Legionnaires’ disease—severe pneumonia (often unilateral and lobar, fever, GI and CNS symptoms. Common in smokers and in chronic lung disease. Pontiac fever—mild flu-like syndrome.

Answer 90

``` Mycoplasma •  Another atypical. 1/3 of Outpatient CAP –  10d for culture growth •  Mollicutes – bacterium without cell wall •  “Walking pneumonia” •  Can have •  Close quarters •  Pathologic if isolated •  Dx via PCR or Serology •  Not sensitive to Beta-Lactams –  Fluorquinolone or macrolide (z pack) ``` no stain color - grain intermediate cholesterol in the cell membrane, sterols in the membrane -atypical pneumonia because can’t readily culture, walking pneumonia -patchy infiltrate.

Answer 91

Bacterial or Legionella pneumonia

Answer 92

Atypical bacterial (mycoplasma)

Answer 93

viral pneumonia

Answer 94

Influenza pneumonia

Answer 95

``` Pseudomonas Aureginosa •  Gm (-) rod •  You’ll likely be colonized by it •  Lung disease, CF (most common gram negative nosocomial pneumonia, respiratory failure in CF patients, bronchiectasis •  Immune suppressed •  Usually easy to culture •  Double coverage –  B-lactam/FLQN resistance –  Advanced agents ``` Thrives in aquatic environments, hot tub folliculitis Blue ring - oxidase positive and catalase positive Obligate aerobe Causes otitis externa, ecthyma gangrenosom (dalmation) Treatment: piperacillin, aminoglycosides and fluoroquinolones

Answer 96

\ •  In the US, more in the Mississippi River Areas •  Inhalation of dust particles from soil contaminated with bird or bat droppings that contain infectious spores •  Clinical –  (1) Self limited or latent pulmonary involvement – “coin lesions” –  (2) Then can go to….chronic, progressive secondary lung disease •  Lung apices, cough, fever night sweats –  (3) Spread to extrapulmonary sites –  (4) Wide dissemination (especially in the Immune Compromised) •  Target Macrophages –  Can opsonize into them - macrophages with intracellular oval bodies –  Multiply and lyse •  Helper T cells usually see fungal cell wall antigens –  Interferon gamma secreted and activates macrophages and kill IC yeasts •  Also Histoplasma induces macrophages to secrete TNF which recruits and stimulates other macrophages to kill Histoplasma –  NOTE RISK FACTORS FOR PEOPLE ON TNF INHIBITORS! •  Diagnosis by culture or Identification in tissue lesions •  Serologic Antibodies –  2-6wk after infection •  Normal hosts recover 99% unless infective dose high and get entire lung involved •  *Very close clinically to TB (book w/ Tb symbol) •  Very similar to sarcoidosis –  That is why in treating sarcoid, you want to exclude fungal disease before beginning Immune Suppression •  Symptoms are usually anatomically based and self limited •  Disseminated forms in impaired T-Cell suppression (can’t form granulomas) -Granulomas cause compression (granulomas mirror RB, w calcified nodes and nodules in the hilar region) -Broncholithiasis (LN erodes into trachea) -Fibrosing Mediastinitus (exstensive fibrosis of mediastinum from large antigen release – can get Supperior Vena Ceva blockage, airway constriction) -Cavitary Histoplasmosis (in patients which abnormal lungs mold in the cold and yeast in the beast diagnosis by KOH or rapid serum or urine antigen test

Answer 97

``` Blastomycosis •  Blastomyces dermatitidis is a soil-inhabiting dimorphic fungus. •  Central and southeastern United States **great lakes and Ohio river valley •  Forms –  pulmonary blastomycosis •  Usually abrupt onset illness •  Vary radiographic presentation (lobar, diffuse) •  Usually resolves spontaneously –  disseminated blastomycosis –  (rare) primary cutaneous form •  Diagnosis –  Antigen in urine or serum –  BAL shows “Broad-Based Budding yeast” ``` Treatment is in the immunocompetent -litraconazole, systemic infection use amphotericin B Mold in the cold and yeast in the heat -dimorphism. -blasto is typically the same size as RBCs = patchy alveolar infiltrate

Answer 98

Coccidiomycosis •  *Southwestern US, Very pathogenic – *inhalation usually leads to infection –  The fungus seems to block lysosome •  Delayed type hypersensitivity reaction phagosome fusion •  Peripheral eosinophilia common •  *Still usually asympomatic –  10% progress to lung lesions, cough, pleuritic pain and erythema nodosum or erythema multiforme (San Joaquin Valley fever complex), knee pain - travels to one –  1% go to disseminated disease Mold in the cold *spherule of endospores in the body, not yeast. Azoles for local, amphotericin B for systemic

Answer 99

Cryptococcus •  Budding HEAVily encapsulated yeast also ubiquitous in soil •  HIV association •  India Ink stain transmitted by pigeon droppings and found in the soul. Urease positive Spread to CSF and cause meningitis, this is no bueno and very often will lead to permanent neuro deficits Treatment with ampho B, flucytosine and then fluconazole

Answer 100

``` Mucormycosis •  Treatment for Aspergillus can be risk factor •  Can first infect sinuses •  More nodular than aspergillus Necrotic, Cavitation •  90-degree branching ``` transmitted via spore inhalation - diabetic ketone acidosis predisposes infection of this fungus. Invade through cribriform plate in the skull then will continue to cause necrosis of tissue and frontal cortex abscesses -black eschar and necrosis of nasal cavity and eyes, causing neuro deficits and death Amphotericin B

Answer 101

Opportunistic Mycoses -- Candida •  Normal flora in GI and GU tracts, and commonly contaminates cultures -severe diaper rash when exposed to heat and humidity. •  Can be invasive and cause pneumonia though •  Pneumonia from just candida is extremely rare –  Usually from bloodstream infections (not oropharyngeal secretions) –  Can see micro-absscesss and lobar infiltrates •  Rarely treat when isolated in sputum or at bronchoscopy •  More when see signs of disseminated infection oral candida common in asthmatic kids that don’t rinse mouth after use of inhaler -esophagitis Aids defining illness at CD4 of 100

Answer 102

Pneumocystis pneumonia •  Seen in HIV and Immune Suppressed patients –  Immune Suppressed (CXR to right) has more neutrophils on bronchoscopy, fewer cysts on metheneamine silver stains •  Seen more as fungi than protozoa •  Prophylaxis has reduced incidence •  Can be spread airborne – person to person –  Normal immune system individuals can be colonized with it •  Can present fulminant or subacute – dry cough and fever –  HIV patients usually more subacute and bronchoscopy fluid has more lymphocytes and (CD8+) cells, not many neutrophils, more cysts (below) –  HIV candidiasis can predispose •  Tend to see desaturation on exertion Pneumocystis jiroveci – PCP Ping Pong 1. Aid for Aids – Associated with Aids CD4 counts below 200 2. 20-0 – CD4 counts below 200 3. Immunocompromised Cane player and young player – Symptoms are evident in immunocompromised individuals 4. Cracked glass ping pong tables - Will have a ground glass appearance in both lungs 5. BAL water bottle - Broncheolavar lavage for diagnosis 6. Silver discs on the table and ovoid ping pong balls - Methamine silver stain to identify fungus that looks like disc shaped yeasts 7. Backhand, and the jar of ping pong sulfa bottle- Prophylaxis begins when CD4 count is below 200, Bactrim (TMP/SMX) 8. Pentagon paddles – Pentadamine can be used with sulfa allergies

Answer 103

Cytomegalovirus •  Immune Suppressed unique population – Transplant –  Get from CMV+ donor –  Blood products from CMV+ donor –  Reactivation of latent infection in seropositive recipient –  Close contact with CMV infected individual •  “CMV Infection” – evidence of CMV regardless of symptoms or sings •  “CMV disease” – signs and symptoms –  Fever, malaise (vial syndrome) –  Tissue invasive disease (pneumonitis)

Answer 104

1. Low FiO2 (house fire or high altitude) - alveolar oxygen tension is low 2. hypoventilation - alveolar oxygen tension is low A-a gradient would be normal for alveolar oxygen tension. 3. V/Q mismatch high or low (most common cause of hypoxemia) 4. Shunt 5. Diffusion impairment - interstitial lung disease and that’s IT A-a gradient is high

Answer 105

NEONATES (< 4 WK) 1. Group B streptococci 2. E coli ``` CHILDREN (4 WK–18 YR) Viruses (RSV) Mycoplasma C trachomatis (infant s –3 y r) C pneumoniae (school aged children) S pneumoniae Runts May Cough Chunky Sputum ``` ``` ADULTS (18–40 YR) Mycoplasma C pneumoniae S pneumoniae Viruses (eg, inluenza) ``` ``` ADULTS (40–65 YR) S pneumoniae H influenzae Anaerobes Viruses Mycoplasma ``` ``` ELDERLY S pneumoniae Influenza virus Anaerobes H inluenzae Gram ⊝ rods ```

Answer 106

1. Alcoholic: Klebsiella, anaerobes usually due to aspiration (eg, Peptostreptococcus, Fusobacterium, Prevotella, Bacteroides) 2. IV drug users: S pneumoniae, S aureus 3. Aspiration: Anaerobes 4. Atypical: Mycoplasma, Legionella, Chlamydia 5. Cystic fibrosis: Pseudomonas, S aureus, S pneumoniae, Burkholderia cepacia 6. Immunocompromised: S aureus, Pseudomonas, other enteric gram ⊝ rods, fungi, viruses, P jirovecii with HIV 7. Nosocomial- S. aureus, Pseudomonas, other enteric gram negative rods 8. Postviral: S pneumoniae, S aureus, H influenza.

Answer 107

Streptococcus pneumoniae (90%)

Answer 108

Haemophilus influenzae

Answer 109

Klebsiella

Answer 110

pseudomonas aeruginosa also commonly causes CAP in patients with cystic fibrosis and immunocompromise

Answer 111

S. aureus Another buzzword is - IV users - endocarditis hospital acquired pneumonia

Answer 112

Sarcoidosis ``` -african american female stellate inclusions -bilateral lung and hilar adenopathy (90%) -mimics Sjorgren syndrome -can effect many organs -elevated ACE ``` Treatment is steroids

Answer 113

Hypersensitivity pneumonitis - presence of non-caseating granulomas - eosinophils

Answer 114

Idiopathy pulmonary fibrosis aka usual intersitial pnuemonia mortality is within 5-6 years 68%. Only treatment is lung transplant

Answer 115

Breathing in carbon dust Coal worker’s penumoconiosis

Answer 116

-most common occupational lung disease in the world Silicosis

Answer 117

Lung cancer Asbestosis -smoking severely increase the chances of cancer

Answer 118

Surfactant production begins at 28 weeks but adequate levels not reached until 34 Neonatal respiratory distress syndrome

Answer 119

chronic bronchitis at least 3 months of productive cough lasting 2 years

Answer 120

Unlike emphysema, the pulmonary capillary bed is undamaged. Instead, the body responds to the increased obstruction by decreasing ventilation and increasing cardiac output. There is a dreadful ventilation to perfusion mismatch leading to hypoxemia and polycythemia. In addition, they also have increased carbon dioxide retention (hypercapnia). Because of increasing obstruction, their residual lung volume gradually increases (the "bloating" part). They are hypoxemic/cyanotic because they actually have worse hypoxemia than pink puffers and this manifests as bluish lips and faces--the "blue" part.

Answer 121

Bronchiectasis | -the air whirls around, because the dilation the air can’t accelerate out

Answer 122

Embryonic - weeks 4-7: tracheoesophageal fistula, up to tertiary bronchi Pseudoglandular - weeks 5-16: terminal bronchiole Canalicular (weeks 16-25): respiratory bronchiole, respiration capable at 25 weeks Saccular (week 26-birth) - alveoli develop, pneumocytes form, surfactant is getting produced Alveolar (week 36 - 8 yrs) = surfactant production peaks,

Answer 123

rare autoimmune disease of the kidney and lung - clinically begins with hemoptysis, rapidly progressive glomerulonephritis - focal necrosis of alveolar walls with associated intra-alveolar hemorrhage - linear deposits of immunoglobulins and complement along the glomerular basement membrane and alveolar septal walls Treatment: plasmapheresis, immunosuppressive therapy

Answer 124

rare disorder with intermittent diffuse alveolar hemorrhage - usually young children - productive cough, hemoptysis and anemia - favorable response to long term immunosuppression with prednisone

Answer 125

Granulomatosis with polyangiitis (Wegener) autoimmune disease characterized by triad of - bilateral nodular and cavitary lung infiltrates, serology for positive c-ANCA is required - rapidly fatal 1. Upper respiratory tract: perforation of nasal septum, chronic sinusitis, otitis media, mastoiditis. 2. Lower respiratory tract: *hemoptysis, cough, dyspnea. 3. Renal: *hematuria, red cell casts. Tr i a d : 1. Focal necrotizing vasculitis 2. Necrotizing granulomas in the lung and upper airway 3. Necrotizing glomerulonephritis PR3-ANCA/c-ANCA (anti-proteinase 3). CXR: large cavitary nodular densities. Treat with cyclophosphamide, corticosteroids

Answer 126

Squamous cell carcinoma the one type of cancer that can cavitate. Horner’s Pancoast

Answer 127

Adenocarcinoma overexpressed in about 80% of non-small cell cancers if this intercellular tyrosine kinase domain is mutated, sending signals for the nucleus to divide. So give tyrosine kinase inhibitors. And stop the division of lung cancer, it has revolutionized the treatment of lung cancer.

Answer 128

Carcinoid -low grade malignancy, can cause carcinoid syndrome

Answer 129

tuberculosis

Answer 130

``` >=5mm –  HIV -former case of TB -immunosuppressed patient -close contact has TB ``` >=10 mm –  foreign immigrants from country with high incidence -people from high risk settings (jails, hospitals) -children < 4 years 15mm –  healthy people >4 years with low likelihood of TB

Answer 131

Obstructive apnea has the presence of respiratory effort • Central apnea has the absence of respiratory effort • Apnea= Cessation of flow for ≥10 seconds • Hypopnea= Decrease in flow by ≥30% for ≥10 seconds associated with oxygen desaturation or elecrophysiologic arousal • Apnea-hypopnea index= number of apneas and hypopneas per hour * Mild= 5- <15 events per hour * Moderate= 15- <30 events per hour * Severe= ≥30 events per hour

Answer 132

1. Cerebral signs 2. Petechial rash 3. Retinal fat globules

Answer 133

Neutrophil - release chemokines, oxygen radicals, prostaglandins and proteases that damage alveolar epithelium shock, severe trauma, sepsis, acute pancreatitis, massive transfusion and gastric aspiration are all causes PaO2-FiO2 <200 mm Hg

Answer 134

Self-limited inflammation • Most commonly secondary to viral infection • Release of inflammatory cytokines and chemokines including interleukin (IL)-6, tumor necrosis factor-α, and interferon-γ results in : – Tissue edema – Mucus production – Vascular dilation • Nasal irritants, including perfumes, smoke, and cleaning products, can cause a similar constellation of symptoms

Answer 135

• Initial allergen exposure provokes early and late phase immune responses • Early phase: – Allergen recognition by IgE** subunits on mast calls and basophils – Degranulation of mast cells and basophils – Release of pre-formed mediators – Histamine** – Tissue edema – Mucus secretion • Late phase (4-8 hrs after exposure): – Infiltration of leukocytes, eosinophils, basophils, CD4 lymphocytes and monocytes – Second wave of inflammatory mediators next time • Priming of immune response • Repeated allergen exposure results in amplification of mucosal hyper-responsiveness • Due to neural hyper-responsiveness and amplification of mast cells and basophils

Answer 136

Acute Rhinosinusitis • Typically viral etiology • Between 0.5% - 2% of viral rhinosinusitis episodes will progress to acute bacterial rhinosinusitis – Viral-mediated mucosal inflammation and edema causes ciliary dysfunction and obstruction of sinus ostia – Mucus stasis

Answer 137

Chronic Rhinosinusitis • Persistent mucosal inflammation • Numerous theories have been proposed: • Systemic immune dysfunction, Staphylococcal super antigens, Bacterial biofilms, Aberrant immune response to fungus, Dysbiosis (imbalance of the resident microbial population) • Can have nasal polyposis (eosinophilic infiltrate with TH2 helper cells) • May have sensitiivy to Aspirin and NSAIDs • Samter’s triad (Asthma, Chronic rhinosinusitis with polyposis, aspirin/NSAID sensitivity) • Abnormalities in arachidonic acid metabolism – Increased inflammatory products of 5-lipoxygenase pathway – Tx- Steroids

Answer 138

Exudative phase (1st week) – Type I pneumocyte necrosis and sloughing of basement membrane – Congestion of alveolar capillaries, interstitial and alveolar edema, and intra-alveolar hemorrhage. – Hyaline membranes in the region of the alveolar ducts. – Interstitial inflammation –lymphocytes, macrophages and plasma cells • End of first week: – Hyperplasia of the Type 2 pneumocytes that continues throughout the organizing phase Organizing phase (begins after 1 week) • Begins towards the end of the first week • The exudate within the interstitium and alveolar spaces begins to organize • Extensive proliferation of type 2 pneumocytes and fibroblasts along the basement membrane of damaged alveolar septa • Fibroblasts and myofibroblasts proliferate within the interstitium and migrate through breaks in the alveolar basement membrane into the intra- alveolar fibrinous exudate. • Vascular thromboemboli are common • Squamous metaplasia can be seen -hyaline membranes getting resorbed Repair and resolution • Regeneration of type 2 pneumocytes regenerate into type I pneumocytes – allowing restoration of normal alveolar gas exchange. • Exudate transforms into granulation tissue that may undergo resorption as the lung returns to normal Fibrotic chronic phase • Patients who survive 3-4 weeks on a ventilator • Extensive remodeling by dense fibrous tissue • Alveolar spaces and bronchioles may haphazardly enlarge and are surrounded by dense fibrosis • Progressive increase in intra-alveolar fibrosis and collagen In fatal cases, fibrosis progresses for several weeks with extensive reconstruction of lung parenchyma and finally honey comb lung.

Answer 139

1. Insult, i.e. sepsis, trauma, severe pancreatitis - sloughing off bronchial epithelium - necrosis of type 1 pneumocytes 2. Inflammatory cells & cytokines 3. Capillary endothelial & alveolar epithelial injury 4. Increased permeability > protein-rich interstitial and alveolar edema 5. Decreased Surfactant production & function > atelectasis Buzzwords: acute inflammation, edema, hyaline membranes, • Bilateral pulmonary infiltrates on chest radiograph

Answer 140

Valve incompetence due to DVT Transmits high pressures to the superficial capillary veins.

Answer 141

Workup is indicated only if the Great and small saphenous veins are involved. The reason is not the thrombophlebitis itself but rather the high association with concurrent DVT- especially if ST is near junctions of the deep venous system There is also risk that these will progress to the deep system.

Answer 142

Paget-Schroetter Syndrome: compression of subclavian vein as it is going under the clavicle, mechanical event.

Answer 143

second most common inherited thrombophilic disorder Mutation is in the 3’ UTR of the prothrombin gene leading to an increase in prothrombin It is autosomal dominant like protein C deficiency

Answer 144

Factor V Leiden Mutation -factor 5 is resistant to activated protein C. Autosomal dominant, inherited risk factors for DVT all are along with antithrombin 3 deficiency and protein S deficiency.

Answer 145

the gene when inactivated is implicated in primary pulmonary hypertension. bmPR (pulmonary resistance) > leading to proliferation of vascular smooth muscle Classically seen in young adult females. Death is within 2 to 5 years and the only treatment is lung transplant.

Answer 146

It is a cause of secondary pulmonary hypertension. Recurrent emboli lead to reduction in the cross sectional area of pulmonary vascular bed.

Answer 147

Right heart catheterization at rest 1. Mean PA pressure >= to 25 mm Hg 2. Pulmonary capillary wedge pressure =< 15 mm Hg

Answer 148

D-dimer tests are used to help rule out the presence of an inappropriate blood clot (thrombus). Some of the conditions that the D-dimer test is used to help rule out include: Deep vein thrombosis (DVT) Pulmonary embolism (PE) Its a highly sensitive test so a negative test means you have high certainty no PE. Together with clinical stability and a low Wells Score, they will likely have excellent outcome.

Answer 149

1. dyspnea 2. pleuritic chest pain 3. Hemoptysis 4. Hypoxemia 5. Increase A-a gradient 6. Respiratory alkalosis (from hyperventilation)

Answer 150

Stages 1 - 3a Beyond needs radiation

Answer 151

- nonfunctioning mass of lung tissue - NO communication w/ tracheobronchial tree - blood supply from systemic circulation - intralobar (75-90%) - left lower lobe - recurrent infection Extralobar - outside lung, has its own visceral pleura, congenital anomalies

Answer 152

mediastinum location thin walled structures that can occur anywhere along embryonic airway - lined with respiratory mucosa Presentation is - recurrent infection - compression, cough, dyspnea, wheezing

Answer 153

1. Congenital diaphragmatic hernia - tachypnea, dyspnea, cyanosis, absent bowel sounds, scaphoid abdomen 2. Potter syndrome - bilateral renal agenesis or bilateral multicystic dysplastic kidney, reduced fetal urine excretion, (lack of) oligohydramnios causing compression

Answer 154

```  Tall  Thin  Marfan syndrome  Smoking tobacco  Smoking marijuana • Catamenial – associated with menstrual cycle. ``` * Alveoli rupture at the point where the alveolar base meets the bronchovascular sheath. * Air dissects along the vascular sheaths towards the mediastinum and into the hilum and mediastinal soft tissues. * The mediastinal parietal pleura ruptures, and a pneumothorax develops.

Answer 155

• Physical findings do not usually manifest until pleural effusions exceed 300 mL • Dullness on chest percussion • Decreased tactile fremitus • Egophony • Decreased breath sound in chest auscultation • Decreased lung excursion

Answer 156

* aspiration of infective material: - abscess is a form of liquefactive necorsis resulting from neutrophilic enzymatic degradation. * a large hole in the lung with accumulated debris along one edge of the cavity. - vulnerable patients include those with diminished cough reflex, consciousness, seizure disorders, elderly, alcoholics - anaerobic bacteria are commonly cultured (fusobacterium, bacteroides) - chest xray reveals a cavitary lesion with an air-fluid level •  Infection causes necrotic lung tissue to cavitate •  Bacteria more associated with cavitation/abscess 1–  Actinomyces (Gm+ anaerobe) – alcoholic, poor dental hygiene, post dental procedure, more in immune competent 2–  Nocardia (Gm+ anaerobe) – (weakly acid fast), seen in soil, immune compromised •  Not all cavitations are infectious! –  Wegener’s, Trauma, cysts, cancer also, among other causes, create pulmonary cavity •  Pathophysiology –  Small zones of necrosis in consolidated regions of pneumonia form single or multiple abscesses that erode into bronchi, ultimately resulting in fibrosis

Answer 157

Defects in the cytoskeletal structure of cilia, particularly dynein. Sweat test: A sweat test measures the amount of salt chemicals (sodium and chloride) in sweat. It is done to help diagnose cystic fibrosis. Normally, sweat on the skin surface contains very little sodium and chloride. People with cystic fibrosis have 2 to 5 times the normal amount of sodium and chloride in their sweat. The defective chloride channel prevents reabsorption of ions. During the sweat test camera.gif, medicine that causes a person to sweat is applied to the skin (usually on the arm or thigh). The sweat is then collected on a paper or a gauze pad, and the amount of salt chemicals in the paper or gauze is measured in a lab. Generally, chloride (sweat chloride) is measured.

Answer 158

The sphenopalatine artery is the major blood supply to the nasal mucosa = it is a terminal branch of the maxillary artery

Answer 159

Arterial PO2: decrease Arterial O2 saturation - decrease Hematocrit - increase - arterial PO2 and arterial O2 sat both reamin low because these parameters are both virtually independent of blood hb concentration. The oxygen saturation curve yo

Answer 160

-abnormal communication between the trachea and esophagus caused by a malformation of the tracheoesophageal septum It is generally associated with esophageal atresia and polyhydramnios because of fetus has difficulty swallowing. Results in immediate vomiting after feeding, copious, frothy secretions (air can enter the stomach) and gagging - a nasogastric tube is placed and resistance if felt after several centimeters.

Answer 161

Histoplasmosis

Answer 162

purified protein derivative - tuberculin (outer surface protein) and mycolic acids of the organism.

Answer 163

``` buzzwords" Southern China adult Africa childhood EBV enlarged cervical lymph nodes -pleomorphic keratin cells over a background of lymphocytes ```

Answer 164

This vignette suggests a patient with Pneumocystis jiroveci pneumonia based on the HIV status, physical examination and x-ray findings, and the elevated lactate dehydrogenase level. Prophylactic therapy for P jiroveci pneumonia is indicated for an HIV-positive patient with a CD4+ T-lymphocyte count <200/μL. The standard prophylactic therapy for P jiroveci pneumonia is trimethoprim-sulfamethoxazole (TMP-SMX). This combination, however, is contraindicated for patients with a sulfa allergy, because sulfamethoxazole is a sulfa drug. In these cases, the best alternative treatment is aerosolized pentamidine

Answer 165

From the history, it appears that this man initially experienced nonspecific viral symptoms, but there is not enough information to determine which virus he has. What is clear, however, is that his initial symptoms are distinct from what he experiences on relapse. The radiograph shows that he has lobar pneumonia (lower right lobe), which can be caused by any number of bacterial species. The question that must be asked,therefore, is, “Which viral illness predisposes to subsequent bacterial pneumonia in an otherwise healthy individual?” The classic answer is influenza. The influenza virus is an enveloped, single-stranded RNA virus with a segmented genome that permits reassortment of the genes encoding the hemagglutinin and neuraminidase proteins, resulting in the phenomenon of antigenic shift. Complications of influenza include both viral pneumonia (due to a spreading of the illness into the lower respiratory tract) and bacterial pneumonia. The latter is thought to be due largely to the fact that influenza damages the epithelium of the upper respiratory tract, compromising its ability to keep the lower respiratory tract sterile. Streptococcus pneumoniae, Staphylococcus aureus, and Haemophilus influenzae are the organisms most commonly seen in bacterial pneumonia secondary to influenza. This chest x-ray shows a consolidation in the right lower lobe along with a para-pneumonic effusion, highly suspicious for bacterial pneumonia.

Answer 166

In patients who present with insidious onset of dry cough, low-grade fever, headache, myalgias, nausea, or emesis, an atypical pneumonia should be considered. Atypical pneumonias are mostly caused by Mycoplasma or viruses. Mycoplasma cannot be cultured and is detected by the cold agglutinin test, which measures the agglutination of immunoglobulins when they are cooled. X-ray of the chest is often more impressive than physical examination findings, and is characterized by a patchy interstitial pattern. Treatment consists of antibiotic therapy with a macrolide, usually azithromycin, for five days

Answer 167

.Epiglottitis is a medical emergency, and 90% of patients require surgery to reestablish an airway. At presentation patients with epiglottitis can have little or no respiratory compromise, but this can progress to life-threatening respiratory distress within a matter of hours. Epiglottitis on x-ray film of the neck reveals a “thumbs up” sign (ie, “thumbprint” on radiograph), which correlates with an inflamed epiglottis. Inflammation of the larynx and subglottic trachea is not associated with epiglottitis. Patients with epiglottitis do not have the symptoms or physical findings of conjunctivitis or rhinorrhea. These findings are more typical of croup. Epiglottitis has additional symptoms of drooling and labored breathing. In general, the onset of symptoms is abrupt with epiglottitis and gradual with croup. A typical barking cough is seen with croup, which may eventually lead to inspiratory stridor. Epiglottitis typically presents with stridor and hoarseness. Most of the time, a throat swab in epiglottitis will reveal Haemophilusinfluenzae, not parainfluenza. Parainfluenza is more often seen in croup.

Answer 168

.Of the antimycobacterial drugs, only isoniazid (INH) produces the lupus-like syndrome described above. INH decreases synthesis of mycolic acids. Furthermore, hepatotoxicity is common to many antituberculosis drugs (rifampin, pyrazinamide, and INH).

Answer 169

..Nonselective bblockers are contraindicated in patients with lung disease because they can cause bronchoconstriction by blocking b2-receptors responsible for relaxation of bronchial smooth muscle. Nadolol is a nonselective b-blocker and should not be used in a patient with lung disease. Other nonselective b-blockers include propranolol, timolol, and pindolol. Acebutolol, atenolol, esmolol, metoprolol, and betaxolol are cardioselective b1-blockers that should be favored in patients with lung/airway disease. Although the stem does not specifically state that this patient has lung disease, smoking causes airway hyperreactivity and bronchoconstriction. Adding a nonselective b-blocker could exaggerate these adverse effects of smoking.

Answer 170

``` This patient’s constellation of symptoms is most consistent with Wegener granulomatosis, with the triad of 1. focal necrotizing vasculitis, 2. necrotizing granulomas of the upper and/or lower airways, 3. necrotizing glomerulonephritis. ``` Most patients have positive titers for anti-neutrophil cytoplasmic antibodies with a cytosolic staining pattern (c-ANCA). The disease is caused by systemic granulomatous inflammation, particularly of small- and medium-sized arteries such as those supplying the kidneys and lungs. If not treated with immunomodulating drugs, focal glomerulonephritis can progress to a crescentic form, with ensuing renal failure. ``` -dark colored urine - productive of blood-tinged sputum. -creatinine level of 1.7 mg/dL - ulcerated lesion of the mucosa of the right naris ```

Answer 171

.The patient has signs and symptoms of sarcoidosis, with classic race, pathology (noncaseating granuloma), and x-ray of the chest revealing prominent bilateral hilar lymphadenopathy, which is present in >90% of patients with sarcoidosis. Erythema nodosum, an inflammatory panniculitis, is the most common cutaneous manifestation of sarcoidosis, and frequently presents as bilateral tender red bumps on the shins. Additional features of sarcoidosis include hypercalcemia due to increased activation of vitamin D by activated macrophages.

Answer 172

.This patient likely has diphtheria, an infection caused by the gram-positive rod Corynebacterium diphtheriae. Diphtheria classically presents with a grayish-white pseudomembrane on the pharynx or tonsils; this pseudomembrane should not be disrupted in order to avoid increased absorption of the lethal exotoxin. Fever is usually mild or absent. It is seen very rarely in vaccinated populations but is endemic to certain parts of the world. Culture of C diphtheriae requires tellurite agar (Loeffler medium) to prevent growth of normal upper respiratory tract flora. Colonies will become gray to black within 24 hours. Bordet-Gengou agar is used to culture Bordetella pertussis. Pertussis presents with paroxysmal coughing spells and whooping sounds on inspiration. Chocolate agar is used to grow Haemophilus influenzae. Encapsulated strains of H influenzae cause invasive diseases such as septicemia, meningitis, cellulitis, septic arthritis, epiglottitis, and pneumonia. Nonencapsulated strains are likely to cause otitis media, conjunctivitis, bronchitis, and sinusitis. Sabouraud agar is used to grow fungi. Thayer-Martin agar is a chocolate agar plate, which has VCN antibiotics (vancomycin, colistin, and nystatin) that suppress the growth of endogenous flora while supporting Neisseria gonorrhoeae growth. This patient does not have symptoms of gonorrhea

Answer 173

Ethambutol is active against Mycobacterium tuberculosis, and it is among the first-line agents used to treat tuberculosis (TB) infection (others are isoniazid, rifampin, and pyrazinamide). Ethambutol’s mechanism of action appears to be the inhibition of polymerization of cell-wall precursors. Although the drug generally is well tolerated, its most common adverse effects involve ocular toxicity such as loss of visual acuity and redgreen color blindness, which usually appears several months after the initiation of treatment. Ethambutol usually is used in an anti-TB regimen with rifampin for patients who either cannot tolerate isoniazid or are infected with isoniazid-resistant M tuberculosis. For children, most literature supports a regimen of six months with isoniazid and rifampin, with ad

Answer 174

.Cytomegalovirus (CMV) infection is a common complication in immunocompromised patients following bone-marrow transplantation. Histopathology shows large cells with intranuclear inclusions (so-called “owl’s eyes”) typical of CMV infection.

Answer 175

.This patient most likely has type 1 DM and a resulting ketoacidosis. He has a metabolic acidosis with a large anion gap (>10 mEq) as calculated by the following formula: Anion gap = Na+ - [HCO3 - + Cl-]. This leads to respiratory compensation by deep respiration (Kussmaul’s respiration), resulting in a decrease in blood partial pressure of carbon dioxide. The large anion gap is due to the overproduction of ketones in the absence of insulin production.

Answer 176

.The patient is suffering from the syndrome of inappropriate ADH secretion (SIADH), a condition in which excessive ADH is secreted independently of serum osmolality; this can be seen in a variety of pulmonary diseases (including TB) as well as central nervous system (CNS) disorders that enhance ADH release (eg, stroke, hemorrhage, infection, and trauma) and certain carcinomas (most commonly small cell lung carcinoma). SIADH can also be an adverse effect of some drugs, notably high-dose intravenous cyclophosphamide. Other drugs shown to cause SIADH include carbamazepine, vincristine, vinblastine, cisplatin, amitriptyline, amiodarone, and monoamine oxidase inhibitors. Excessive ADH secretion can lead to nausea, lethargy, seizures, and even coma. The patient’s laboratory values are typical of someone with SIADH, showing hyponatremia, serum hypo-osmolality, urine hyperosmolarity, and decreased hematocrit secondary to dilution. Like lithium, demeclocycline has been associated with nephrogenic diabetes insipidus (DI). Demeclocycline is not known to cause SIADH, the underlying disorder that accounts for this patient’s presentation. In fact, demeclocycline is sometimes used to treat SIADH. Hydrochlorothiazide (HCTZ) is a diuretic that may sometimes result in hyponatremia. However, this patient is presenting with SIADH, and HCTZ is not a known cause of SIADH. HCTZ would be unlikely to account for the degree of hyponatremia (as well as the other laboratory abnormalities) seen in this patient. Like indomethacin, HCTZ can be used to treat nephrogenic DI. Indomethacin has not been associated with SIADH. It is, however, sometimes used to treat nephrogenic DI. Patients with nephrogenic DI typically present with serum hyperosmolality, hypernatremia, and urine hypoosmolality. Answer E is incorrect. Lithium toxicity has been shown to cause nephrogenic DI rather than SIADH. In nephrogenic DI the kidneys are unable to absorb water appropriately in response to ADH. Patients present with production of large quantities of dilute urine, serum hyperosmolality, and hypernatremia. They report both polydipsia and polyuria. Medical treatment of nephrogenic DI may consist of hydrochlorothiazide or indomethacin.

Answer 177

.The patient’s penetrating chest wound opened her intrapleural space to the atmosphere. Therefore, as she attempts to inhale, her thoracic cavity expands but air enters through the wound, equalizing the pressure; this prevents the normal expansion of the lungs. If air is not able to escape through the wound duration exhalation, this is called a tension pneumothorax, in which the quantity of free air in the thoracic cavity increases after each breath.

Answer 178

This man is likely suffering from obstructive sleep apnea (OSA) secondary to extreme obesity (Pickwickian syndrome). During the night he has intermittent cessation of airflow at the nose and mouth. During this progressive asphyxia, he has a brief arousal, restores airway patency, and returns to sleep. This patient’s obesity and elongated uvula are very good indicators of OSA, as are his daytime sleepiness, inability to concentrate, and hypertension. Periodic, recurrent asphyxia has the effect of causing a respiratory acidosis that, when present chronically, is compensated for by renal retention of HCO3 -.

Answer 179

.Legionella pneumophila The patient has a severe, potentially fatal, pneumonia with prominent systemic symptoms. Culture on buffered charcoal yeast extract is the specific clue that the organism is Legionella pneumophila. The disease is respiratory legionellosis, also known as legionnaire’s disease, so named because the disease was first described when it occurred in epidemic form after an American Legion convention at a Philadelphia hotel. Patients tend to be older and may have risk factors, including cigarette use, alcoholism, diabetes, chronic illness, or immunosuppressive therapy.

Answer 180

. Interstitial (or idiopathic) pulmonary fibrosis (IPF) is a chronic, progressive fibrotic disorder of the lower respiratory tract that affects older adults. It is characterized by the abnormal proliferation of mesenchymal cells, disruption of collagen structures, and impaired gas exchange. The exact pathogenesis of IPF is still unknown. If not treated, IPF often results in death within five years. Lung transplantation is currently the only “cure” for this disease. On x-ray of the chest, IPF usually is seen best in the lower parts of both lungs as white lines in a netlike pattern

Answer 181

Legionella pneumophila is an aerobic, gram-negative rod that causes Legionnaire’s disease, a condition in which patients develop acute, severe pneumonia and a high fever. Other signs and symptoms include hyponatremia (which is unique to this pneumonia) and CNS changes. Legionnaire’s disease is one of the most common causes of community-acquired pneumonia but is identified as the cause in only 3% of cases. The organism is present only in water sources (eg, air conditioning systems, whirlpools, mist sprayers) and causes infection when aerosolized water droplets are inhaled. Transmission is not by person-to-person contact. Typically, more severe illness is seen in patients who are >50 years of age, those who smoke, and those whose Gram stain shows neutrophils and very few organisms, as in this case. Treatment is with erythromycin, because L pneumophila produces a b lactamase that renders it resistant to penicillin derivatives.

Answer 182

.The patient is suffering from TB, with the causative organism (Mycobacterium tuberculosis) seen as red on acid-fast stain. Symptoms include fever, night sweats, chills, cough, and weight loss. His treatment regimen will include isoniazid and other antimycobacterial agents. Isoniazid inhibits mycolic acid synthesis in the mycobacterial cell wall. Because of rapid development of resistance, isoniazid should never be used alone to treat active TB. Isoniazid depletes pyridoxine (vitamin B6), which is required for the production of dopamine, epinephrine, norepinephrine, and monoamine neurotransmitters. Hence, one of the adverse effects of isoniazid therapy is peripheral neuropathy, which can be prevented by co-administration of vitamin B6.

Answer 183

This child has measles complicated by pneumonia. Pneumonia complicates approximately 4% of measles cases in the United States and as many as 50% of cases abroad. Clinically, this child has a high fever, Koplik’s spots, maculopapular rash, and CT of the chest showing diffuse interstitial involvement. Measles-infected respiratory cells will fuse and form multinucleated giant cells, which can be detected in sputum samples. Measles is a member of the Paramyxoviridae family, a group of negative-sense, singlestranded RNA viruses. In immunocompromised hosts, measles pneumonia may evolve to giant cell pneumonia, which is often fatal

Answer 184

.This patient is showing signs of Cushing syndrome with a buffalo hump and purple striae. Cushing syndrome is caused by an excess of cortisol either because of a pituitary adenoma producing excess ACTH, an adrenal adenoma producing excess cortisol, or ectopic ACTH production by a neoplasm. This man’s smoking history and lung nodule shown on chest radiography point to lung cancer. Taken together with ectopic production of ACTH, this patient has paraneoplastic syndrome, with ectopic production of ACTH by the malignant lung mass. Of the different histological classifications of lung cancer listed above, small cell carcinoma is the most likely in the case for several reasons: Squamous cell and small cell carcinomas are most closely linked to smoking history (>98% are associated with smoking) and both present as central lesions such as that shown on the x-ray film. Additionally, tumors producing ACTH or ADH are usually small cell carcinomas.

Answer 185

.This question requires knowledge of both the anatomy and the physiology of the sucking chest wound, as described in this patient. A penetrating wound to the chest can puncture the pleura, making an opening for air to be sucked into the pleural space. With inspiration, the diaphragm descends, lowering the intrapleural pressure. If there is a communication directly between the pleural space and the outside world, air is sucked into this negative-pressure space and collapses the lung. Pneumothorax is seen on x-ray of the chest as a collapsed lung with a mediastinum shifted away from the collapsed lung. With pneumothorax, the patient should be assessed for signs and symptoms of hemodynamic compromise. This patient, for example, is hypotensive, tachycardic, and tachypnic, and therefore requires urgent management.

Answer 186

B-agonists such as albuterol may cause potassium to shift into cells, resulting in hypokalemia. This may lead to ECG abnormalities due to destabilization of cardiac cell membranes, the classic examples of which are U waves. Short-acting b-agonists such as albuterol are used in the treatment of acute asthma exacerbations because of their relaxing effects on bronchial smooth muscle. Long-acting β-agonists such as salmeterol are used for prophylaxis of bronchospasm.

Answer 187

This describes Bacillus anthracis, which can cause cutaneous anthrax, inhalation anthrax, and GI anthrax. This patient had inhalation anthrax (also known as “wool-sorter’s disease”), which usually has two phases: the initial phase characterized by malaise, dry cough, and chest pressure that resolve in a few days; and the second phase in which patients suddenly develop acute respiratory distress and hypoxemia followed by hemorrhagic mediastinitis and bloody pleural effusions. A classic radiologic finding is mediastinal widening. If a patient is not rapidly treated with penicillin, doxycycline, ciprofloxacin, or levofloxacin, systemic infection can cause septic shock (due to exotoxins produced by the bacteria) and death within 24 hours. Spores from sheep or goat skin are the primary mode of transmission in this kind of anthrax. Interestingly, B anthracis is the only medically relevant bacteria with a protein capsule.

Answer 188

This patient is most likely suffering from a spontaneous pneumothorax. Caused by the rupture of a small apical bleb on the surface of the lung, spontaneous pneumothoraces typically present in tall young men. The patient usually has sudden pain and dyspnea. Examination will show decreased breath sounds and hyperresonance on the affected side. X-ray of the chest shows overexpansion of the rib cage and an elevated hemidiaphragm on the affected side. This paradoxical abdominal motion occurs because of the negative intrathoracic pressure that causes the fatigued diaphragm to be pulled into the thorax on the right side. Spontaneous pneumothorax is treated by inserting a chest tube to remove the air from the pleural space. It is possible that this man could have emphysema due to an a1-antitrypsin deficiency, but in that case it would not present this acutely.

Answer 189

Working in a shipyard is associated with asbestos exposure. Chronic inhalation of asbestos fibers can result in asbestosis, which is marked histologically by ferruginous bodies that stain positively with Prussian blue. Asbestosis, unlike most other pneumoconioses, results in marked predisposition to bronchogenic carcinoma and to malignant mesothelioma. Smoking and asbestos exposure together greatly increase one’s risk of developing bronchogenic carcinoma.

Answer 190

This child suffers from a congenital diaphragmatic hernia caused by the failure of the diaphragm to properly form and close. The presence of bowel sounds in a lung zone indicates that abdominal contents have herniated past the boundary of the diaphragm into the thorax. The developing diaphragm is derived from the Septum transversum, Pleuroperitoneal folds, Body wall, and Dorsal mesentery of the esophagus. These four components can be remembered by the mnemonic “Several Parts Build the Diaphragm.”

Answer 191

This patient is likely suffering from a TB infection that was reactivated by her use of etanercept. The x-ray of the chest shows a dense cavitary apical lung lesion that is highly indicative of a reactivated TB infection. Etanercept is a fusion protein that contains two identical tumor necrosis factor (TNF)-receptor monomers fused to a human IgG Fc domain. Therefore, it acts as a TNF antagonist. In TB infections, TNF (secreted by activated macrophages) recruits monocytes to form the epithelioid granulomas required to contain the mycobacteria. When TNF is effectively removed from the infection site (by drugs or other forms of immunosuppression), patients face an increased risk of reactivation with caseation and cavitary lesions.