Pulmonary Infections_Dr. Shiv Flashcards
List some common pulmonary infections we went over in this section.
Pneumonia Lung Abscess TB Fungal infections : Aspergillosis Parasitic infection : hydatid cyst URTIs
What is the general definition of pneumonia?
Pneumonia is an infection of the pulmonary parenchyma
What is CAP (community-acquired pneumonia)?
Pneumonia that is acquired in the communityoutside of health care facilities. Compared with health care–associated pneumonia, it is less likely to involve multidrug-resistantbacteria. Although the latter are no longer rare in CAP they are still less likely.
What is (HCAP/MCAP) Health/Medical Care-Associated Pneumonia?
an infection associated with recent exposure (within 3 months) to thehealth caresystemincluding hospital, outpatient clinic,nursing home,dialysiscenter, chemotherapytreatment, orhome care. HCAP is sometimes called MCAP (Medical Care–associated pneumonia).
What is Hospital-acquired pneumonia (HAP)?
is acquired in ahospitalthat occurs 48 hours or more after admission, and likely to involvehospital-acquired infections, with higher risk ofmultidrug-resistantpathogens.
Ventilator-associated pneumonia (VAP)
occurs in patients onmechanical ventilationthat arises more than 48 to 72 hours after endotracheal intubation.
A 32 years old male was brought to Emergency Room for Traumatic Brain Injury (TBI) due to high-velocity road traffic accident 30 mins back. He was unconscious at that time with GCS (Glasgow Coma Scale) of 5, HR of 92/min, BP of 98/54 mmHg, RR of 20/min and SpO2 of 84% which was still falling so e was intubated with cuffed endotracheal tube and put on Ventilator for invasive ventilation. There was past medical history of Hypertension with dyslipidemia and patient is on statins with ACE inhibitor. There was no other previous significant surgical history. After 30 hours of intubation and invasive ventilation, patient showed consolidation in middle lobe of right lung and diagnosed for Pneumonia. On the basis of this clinical vignette, which of the following type best describes patient’s condition?
A. CAP B. HAP C. VAP D. MCAP E. Sorry, Not sure.
A. CAP (community-acquired pneumonia)
Be able to compare and contrast these different types of pneumonia.
Reproduce chart if possible.
What is your diagnosis and why?
Lobar pneumonia
Involves single lobe
Unilateral
Air bronchogram
What is your diagnosis and why?
Interstitial pneumonia
Involves interstitial space
Ground glass appearance
Bilateral, symmetrical
What is your diagnosis and why?
Bronchopneumonia
Central bronchi involved
Patchy bilateral disease
asymmetrical
What are ways that microorganisms gain access to the lower respiratory tract?
Aspiration (Impaired consciousness, impaired gag reflex, increased GI reflux)
Inhaled contaminated droplets
Hematogenous spread (rare)
Contiguous extension (rare)
How does the defense mechanism of the body become impaired when one has pneumonia?
Chemical mediators from immune cells lead to fever, capillary leak, increased WBCs, infiltrates, hemoptysis, cough, rales, hypoxia, increased RR/Drive, Respiratory alkalosis.
What are the 2 classifications of etiological agent that can be found in community-acquired pneumonia?
Typical or Atypical
What is the most common cause of CAP? (pathogen)
Strep pneumonia
What are some newly identified pathogens that are causes of CAP?
hantaviruses, metapneumo-viruses and the coronavirus.
List the common microbial causes of CAP by site of care. List in descending order of frequency. Just be familiar with about 4 of these that are common pathogens for pneumonia.
Reproduce chart.
Do all forms of pneumonia present with fever and cough?
yes
Chills or rigors when one has bacterial pathogens that cause pneumonia in their body is a sign of what?
toxemia
Describe the characteristic of cough in pneumonia?
Cough may be either non-productive or productive of mucoid, purulent, or blood-tinged sputum.
Cough, from any etiology, may be associated with hemoptysis.
T/F. Severe infection in pneumonia patients is not associated with dyspnea.
False.
Is associated with dyspnea
Chest pain result from what when a patient has pneumonia?
inflammation of the pleura
What are some GI symptoms that may occur when one has pneumonia?
nausea, vomiting, and/or diarrhea
What are the main diagnostic hallmarks of pneumonia?
dyspnea, high fever, and an abnormal chest x-ray is main hallmark
Know how different organism present.
Reproduce chart.
Upon Physical Exam, what may one with pneumonia present with?
Finding vary by degree of pulmonary consolidation and presence or absence of significant pleural effusion
abnormalities of vital signs
altered mental status
Tactile fremits increases upon palpation
Percussion dull
Auscultation Rhonchi, crackles, bronchial breath sounds, pleural friction rubs
Septic shock and evidence organ failure.
Are specific sputum color diagnostic of etiology behind the pneumonia?
no
Infections often with “dry” or nonproductive cough preferentially involve what areas of the lung?
interstitial space and more often leave the air spaces of the alveoli empty. That is why there is less sputum production.
Pathogens that produce dry cough.
-Mycoplasma • Viruses • Coxiella • Pneumocystis • Chlamydia
What is characteristic of X-rays in individuals who have atypical pneumonia?
X-rays lag behind clinical findings
What type of imaging is this? (Tool) What are these X-rays indicating?
Chest Skiagram
Consolidation from left to right:
Rt lower lobe consolidation, Rt middle lobe consolidation, Rt upper lobe consolidation
Is it possible to make a specific diagnosis of the cause of pneumonia from history and examination?
no; impossible
Describe what are some characteristic features of pneumonia upon lab investigations.
Leukocytosis (elevated white blood cell count) is often present, but is a nonspecific marker of infection.
Blood Cultures are positive in 5% to 15% of cases of CAP, particularly with S. pneumoniae.
What are the best ways to first try to determine a specific microbial etiology in cases of pneumonia. Unfortunately, many organisms will not be detected by this method.
Sputum gram stain and sputum culture
The term atypical pneumonia has what characteristic Gram Stain pattern? (explain)
not visible on Gram stain and not culturable on standard blood agar. The use of sputum stain and culture is somewhat controversial because of their low sensitivity.
Even after thorough sputum examination, no etiology is found in at least 50% of cases.
What is the treatment for CAP (outpatients)? (If previously healthy and no antibiotics in past 3 months, Comorbidities or antibiotics in past 3 months)
If previously healthy and no antibiotics:
A macrolide (Clarithromycin or Azithromycin)
Doxycycline
Comorbidities or Antibiotics in past 3 months
A respiratory fluoroquinolone (moxifloxacin, gemifloxacin, levofloxacin)
A B-lactam (amoxicillin) plus a macrolide
What is risk stratification?
Tool used for determination of site of care.
These rules have been used to identify patients who can be safely treated as outpatients and those who require hospitalization because of high risk of complications.
How does the CURB-65 point system work for determining treatment of pneumonia?
In CURB-65, 1 point is allotted for each of the following risk factors:
Confusion
Uremia (BUN ≥19 mg/dL or >7mmol/L)
Respiratory rate > 30 breaths/min
SystolicBP< 90 mm Hg or diastolic BP ≤ 60 mm Hg
Age ≥65yr
Scores can be used as follows:
0 or 1 points: Risk of death is < 3%. Outpatient therapy is usually appropriate.
2 points: Risk of death is 9%. Hospitalization should be considered.
≥ 3 points: Hospitalization is indicated, and, particularly with 4 or 5 points, ICU admission considered.
In the treatment of pneumonia are hypoxia and hypotension as single factors a reason to hospitalize a patient?
yes
For patients with pneumonia, can an X-ray tell the severity of hypoxia?
no
What are some Inpatient treatment plans for CAP? (non-icu)
non-ICU
A respiratory fluoroquinolone [Moxifloxacin
A β-lactam [Cefotaxime (1–2 g IV q8h), Ceftriaxone plus a macrolide
Treatment for CAP Inpatients, ICU
B-lactam plus azithromycin or fluoroquinolone
How to you treat CAP if pseudomonas is consideration?
B lactam plus fluoroquinolone
or
B lactam plus aminoglycoside
or
B-lactam plus amino glycoside plus and anti-pneumococcal fluorquinolone
In CAP if CA-MRSA is a consideration what is the treatment plan?
Linezolid or Vancomycin
What are some supportive measure for treating CAP?
Adequate Hydration,
Antipyretics,
Analgesics,
O2 therapy (for patients with hypoxemia),
Assisted Ventilation,
Prophylaxis against thromboembolic disease
Early mobilization improve outcomes for patients hospitalized with pneumonia.
Cessation counseling should also be done for smokers.
What are some complications of CAP?
Failure to Improve Respiratory failure, Shock Multi-organ failure, empyema Exacerbation of comorbid illnesses Metastatic infection (e.g., brain abscess or endocarditis), Lung abscess, Complicated pleural effusion
Thoracentesis
Analysis of a pleural effusion can sometimes be useful to determine the presence of an empyema if the diagnosis is unclear. Any new large effusion should be analyzed. Empyema is an infected pleural effusion. Empyema acts like an abscess and will improve more rapidly if it is drained with a chest tube.
This tool can be used to remove the fluid from the lungs.
What are these images indicative of from left to right?
Pleural Effusion
Mild
moderate
severe
What forms of CAP are preventable with vaccination?
influenza and pneumococcal
What is the follow up plan for an individual with CAP?
Fever and leukocytosis usually resolve within 2–4 days but physical findings may persist longer.
Chest radiographic abnormalities are slowest to resolve (4–12 weeks).
Patients may be discharged once their clinical conditions are stable.
A follow-up radiograph can be done ~4–6 weeks later.
Persistence of an infiltrate raises suspicions of TB or an underlying, possibly malignant endobronchial lesion.
Patients with HAP have a higher incidence of what pathogens infiltrating their body?
Gram-negative bacilli such as E. coli or Pseudomonas
What is the main difference in management of HAP from CAPs?
macrolides (azithromycin or clarithromycin) are NOT acceptable as empiric therapy
What is treatment of HAP centered around?
therapy for Gram-negative bacilli
What treatment is used for HAP? (drugs used)
Antipseudomonal cephalosporin’s
or
antipseudomonal penicillin or Carbapenems (imipenem, doripenem)
Piperacillin and ticarcillin are always used in combination with what drugs in the treatment of HAP?
In combo with a B-lactam inhibitor such as tazobactam or clavulanic acid
What are the Treatment plans of HAP for patients without risk factors for MDR pathogens?
Ceftriaxone or Ertapenem or Ampicillin/sulbactam or moxifloxacin or all the floxacins
What is the antibiotic treatment plan for patients of HAP with risk factors of MDR pathogens?
B-lactam plus a second agent active against gram negative bacteria plus gram-positive bacteria
What is a Lung Abscess
is a necrotizing lung infection characterized by a pus-filled cavitary lesion.