Pulm 2 Flashcards
Actinomycosis
- Slowly progressive dz due to g(+) anaerobic bacteria
- Orgs colonize mouth, colon, vagina (think dental caries, poor dentition)
- Alcoholics ^ed risk
- Filamentous branching patterns & sulfur granules
TX: PCN
Normal trancheal pO2 and normal alveolar pO2
Trach:
150 mmHG
Alv:
104 mmHg
Perfusion-limited?
Think at rest
Diffusion-limited?
Think exercise, emphysema, and pulm fibrosis (can’t get enough O2 to caps b/c of thickness
O2 does not equilibrate by the time it meets the end of the capillary (20mmHg from alveolus only gives 10mmHg to cap)
Chronic granuloatous disease is deficient in what?
NADPH oxidase
O2 to O2 (superoxide) within phagolysosomes => intracellular killing of orgs in phagosomes
X-linked
Presentation of pts w/ CGD
- Recurrent bacterial and fungal infections (catalase positive ones)
- PNA
- Skin/organ abscesses
- Suppurative adenitis
- Osteomyelitis
- Diffuse granuloma formation
Diagnostic tests of CGD
Measure PMN superoxide production
- DHR flow cytometry (preferred — fluorescent green pigment)
- NBT testing (doesn’t turn blue like normal)
Major virulence factor of S. pneumo
Polysaccharide capsule
Inhibits phagocytosis
Polycythemia
EITHER:
- Increased RBC mass (ABSOLUTE)
- Normal RBC mass w/ decreased plasma volume (RELATIVE)
> 52% in men
48% in women
How do you differentiate between absolute and relative erythrocytosis?
- Direct measurement of RBC mass
- Can’t use Hct or Hb levels
Causes of absolute erythrocytosis?
Primary:
- Polycythemia vera (RBC, WBC, plt increase)
Secondary:
- Only RBC increase
- Hypoxia
- Erythropoietin producing tumors
Causes of relative erythrocytosis
- Dehydration
- Excessive diuresis (e.g. CHF emergent tx)
Hypoxic secondary erythrocytosis indicators?
- SaO2
Left HF signs in a person w/ recent MI
- Dyspnea
- Bibasilar crackles (at the lower lobes)
- S3
Due to decreased CO from LV => high end-diastolic pressure
Why do you get dyspnea from L. HF?
high end-diastolic pressure => ^ed hydrostatic pressure in pulm circulation => transudation of fluid into interstitium
Causes decreased lung compliance (can’t stretch b/c fluid distorts lung tissue)
What type of channel is the CFTR protein in CF?
ATP-gated chloride channel
AR — ∆F508 on chromosome 7
Sarcoidosis dysregulated immune response
Th1 => secretes IL-2, IFN-gamma (aka cell-mediated)
IL-2: autocrine proliferation of Th1
IFN-gamma: activates macros => granuloma formation
Humoral immune response - which type of CD4+ helper T cells?
Th2
Products:
- IL4 (IgE)
- IL5 (eos and IgA)
Dust inhaled 10-15 microm. How does the body clear it?
Trapped in upper airways
Dust inhaled 2.5-10 microm. How does the body clear it?
Mucociliary transport
Dust inhaled
Phagocytosis
Reaches terminal bronchioli and alveoli
Alveolar macros MOA
- Take up dust => activation
- Release GFs (PDGF, IGF)
- Stimulates fibroblasts to proliferate/produce collagen
- Inflammation
Pneumoconiosis arises b/c of inflammation and fibrosis of interstitium
Stages of lobal pneumonia
1) Congestion — 24 hrs
2) Red Hepatization —2-3 days
3) Gray hepatization — 4-6 days
4) Resolution
Congestion macro and micro appearance
Macro:
- Affected lobe is red, heavy, boggy
Micro:
- Vascular dilatation
- Alveolar exudate
- Alveoli containing bacteria
Red hepatization macro and micro appearance
Macro:
- Red, firm lobe
- Liver-like
Micro:
- Alveolar exudate contains erythrocytes, PMNs, fibrin
Gray hepatization macro and micro appearance
Macro:
- Gray-brown firm lobe
Micro:
- RBCs disintegrate
- Alveolar exudate contains PMNs & fibrin
Resolution macro and micro appearance
Macro:
- Restoration of normal architecture
Micro:
- Enzymatic digestion of exudate
How do you treat group B strep in pregnant women?
Test at 35-37 wks
INTRApartum antibiotics (PCN or amp)
Prevents neonatal GBS sepsis, PNA, and meningitis
Budding yeasts w/ thick capsules? Immunocompromised?
THINK
Cryptococcus neoformans
Stained w/ mucicarmine
Cryptococcus neoformans complication in immunocompromised individuals
Meningoencephalitis
HIV, sarcoidosis, leukemia, high dose steroids
Sx of meningoencephalitis b/c of c. neoformans
- HA
- N/V
- Confusion
CSF w/ india ink => budding yeasts w/ halos (peripheral clearings due to thick polysaccharide capsules)
Advantages of PPSV23
Decrease incidence of replacement strains due to lack of mucosal immunity
But only moderate levels of intermediate-affinity ABs
Advantages of PCV13
- Increased efficacy in elderly & children
OSA
- Recurrent obstruction of upper airway during sleep
- Each episode => reduced ventilation => transient hypercapnia & hypoxemia
- Systemic and pulm vasoconstriction
What can prolonged, untreated OSA cause?
- Pulm HTN
- RHF
Also:
- a. fib
- arrhythmias
- CAD
- ^ed risk of sudden cardiac death
Normal CD4+ count?
400-1400
PNA organism in a 34y HIV+ w/ CD4+ of 800?
S. pneumo
PNA organism in a 34yo HIV+ w/ CD4+
Pneumocystis jiroveci
Thick-walled spherules packed w/ endospores
Lung organism?
Coccidioides immitis
Pulm TB infection creates caseating granulomas using which cell mediators?
CD4+ T lymphs
Macros
Normal bronchi are lined with…?
Pseudostratified ciliated columnar cells
Interspersed w/ goblet cells (mucus production)
Smoking changes lining of bronchi to what…?
Stratified squamous metaplasia
Similar to Barrett esophagus
Exercise’s effect on pCO2
- Increases pCO2 of mixed venous blood
- Due to increased skeletal muscle CO2 production
Homeostatic => maintains arterial blood gas and arterial pH near resting levels
Enveloped viruses are inactivated by what?
- Ether and other organic solvents
- Dissolves lipid bilayer that makes up outer viral envelope
Loses infectivity
PCWP in ARDS?
Normal
ARDS is noncardiogenic pulmonary edema
ANOVA measures what?
compares difference of means of 2 or more groups
T-test measures what?
Compares the difference between means of 2 groups
Pulm infections in alcoholics. Common bugs?
- Bacteroides
- Prevotella
- Fusobacterium
- Peptostreptococcus
- S pneumo
Clindamycin MOA
- Binds to 50s ribosomal subunit
- Disrupts protein synthesis
Covers anaerobes and G(+) orgs
Thoracentesis should be performed where?
- Above 8th in midclavicular line
- above the 10th rib along the midaxillary line
- Above 12th rib along the posterior scapular or paravertebral line
Thoracentesis at risk for penetrating which structures?
Abdominal structures
Liver definitely
Microscopic features of chronic bronchitis
- Thickened bronchial walls
- Lymphocytic infiltration
- Mucus gland enlargement
- Patchy squamous metaplasia
Cigarettes is leading cause
Complications associated w/ concentrated O2 tx for neonatal respiratory distress syndrome
Retinopathy of prematurity/retrolental fibroplasia
- Abnormal retinal neovascularization => major cause of blindness
- Due to up-regulation of VEGF when returned to room air
