Respiratory Tract Infection Flashcards
What are common upper respiratory tract infections?
- rhinitis
- sinusitis
- otitis
- pharyngitis
- laryngotracheitis
- epiglottitis
- bronchitis
Rhinitis is caused by what?
- rhinovirus (30%)
- coronavirus (10%)
- parainfluenza
- influenza
- RSV
- adenovirus
What causes sinusitis?
many viral, some bacterial (strep pneumo, H flu, moraxella, and oral anaerobes)
-treat with ampicillin, amoxicillin, tmp-sulfa, amox-clav
What causes pharyngitis?
viral 70%
strep throat
What causes epiglottis?
H flu group A strep H parainfluenzae Emergency ENT consultation -Amox-clav, amp-sulbactam, 3rd generation cephalosporin
What causes acute bronchitis?
self limited infection/inflammation of large airways
cough> 5days, purulent sputum
Etiology: majority viral 1. influenza 2. parainfluenza 3. RSV 4. coronavirus 5. adenovirus 6. rhinovirus (same as sinusitis)
Bacterial
- mycoplasma
- strep pneumo
- H flu
- Chlamydophila
- B pertussis
treatment is symptomatic, routine antibiotics are not suggested, antitussives and mucolytics usually aren’t helpful
What are the signs and symptoms of pneumonia?
cough, sputum, fever, shortness of breath
signs of consolidation on exam, elevated wbc
Risk factors: old age, pulmonary disease, smoking, recent viral illness, diabetes, chronic renal disease, immunodeficiency
What are the diagnostic tests for CAP?
- CXR
- if there is a pleural effusion it should be sampled
- flu test
- yield on blood sputum cultures is low
What are the signs of typical of community acquired pneumonia?
- Acute onset of symptoms (cough, sputum, fever, shaking chills)
- Lobar infiltrate
- gram stain with PMNs and organisms
What are common bugs of typical CAP?
- Strep pneumo
- H flu
- moraxella catarrhalis
- staph aureus
no organisms found in 30-50%
What is the most common cause of typical CAP?
strep pneumo
- acute onset fever, shaking chill, SOB, pleuritic chest pain
- rusty sputum, lancet shaped diplococcus
What are the symptoms of atypical CAP?
- subacute onset of symptoms
- milder symptoms
- prodrome
- negative gram stain
What are the most common bugs of atypical CAP?
- Mycoplasma
- Chlamydia
- Legionella
- viruses
What are symptoms of legionella pneumophila?
headache, myalgias, high fever, fatigue, cough, sputum
- can progress to multi-organ system failure
- flourishes in artificial aquatic environments
- infection with inhalation or drinking contaminated water
- diagnosis by urinary legionella antigen
What are the most common etiologic agents causing viral atypical CAP?
- influenza
- RSV
- adenovirus
- parainfluenza
- can develop secondary bacterial infections
- seasonal
What are typical symptoms of influenza?
fever, cough, headache, sore throat, myalgias
can cause pneumonia, respiratory failure, death
-in flu season can, test, isolate and start therapy if within 48 hours of start of symptoms
Therapy: Oseltamivir or zanamivir
Best prevention: yearly flu vaccine
What are the symptoms of CAP in pediatrics?
tachypnea, fever, cough dyspnea
What are the most common bugs in CAP pediatrics?
Under 2: viral (RSV, rhinovirus)
5-10 yrs old: mycoplasma
10-16: s pneumo, chlamydophila
Emerging pathogens:
Human metapneumovirus
Human Bocavirus
Simkania Negevensis
What is the therapy for CAP?
Outpatient:
- Macrolide or doxycycline
- If co-morbid illness or recent antibiotics, a respiratory fluoroquinolone
Inpatient, non ICU
- respiratory fluoroquinolone
- B lactam + macrolide
Inpatient ICU:
-B lactam + macrolide or fluoroquinolone
If pseudomonas is a concern:
- Anti-pseudomonal B lactam + respiratory fluoroquinolone
- Anti-Antipseudomonal b lactam + macrolide + aminoglycoside
How long do you give antibiotics?
at least 5 days, longer if the patient is sick or the initial empiric choices were wrong
What are diagnostic criteria for HAP?
-fever, new infiltrate, leukocytosis, and change in sputum
What are the bugs that cause HAP?
become colonized with gram negative rods:
- klebsiella
- e. coli
- enterobacter
- proteus
- serratia
- pseudomonas
- acinetobacter
organisms are aspirated
host defenses are lowered by coexisting illness
What are risk factors for HAP?
- mechanical ventilation
- chronic lung disease
- CHF
- > 60
- Head trauma
- shcock
- decreased mental status/coma
What are risk factors for HAP that is multidrug resistant?
- antibiotics within 90 days
- inpatient for >5 days
- residence in NH
- dialysis
- immunosuppression
What is the therapy for HAP?
Early, broad empiric therapy Narrow by culture results or lack there of 1. antipseudomonal cephalosporin 2. antipseudomonal carbapenem 3. b lactam/ b lactamase 4. vancomycin if worried about MRSA
What is chronic pneumonia?
subacute onset of symptoms -typically >6 weeks
caused by slow growing organisms
What are common bugs with chronic pneumonia?
- mycobacterium (tb or atypical)
- nocardia
- actinomyces
- endemic fungi
- coxiella
- tularemia
- anatomic problem
What does lung abscess lead to? What bugs cause lung abscesses?
-leads to tissue destruction and necrosis, suppuration, cavitation
anaerobic mouth organisms (bacteroides, fusobacterium, peptostreptococcus), aerobic and anaerobic streptococcus, GNR
caused by : aspiration, post-pneumonic, septic emboli
What is empyema?
infection spreading to the pleural space
What causes neutrophil dysfunction or deficiency, what organisms cause pneumonia with this deficiency?
Causes: chemo, leukemia, chronic granulomatous disease
organisms:
- gram negative rods (pseudo, Hflu)
- staph
- aspergillus
- candida
What can cause T cell dysfunction or deficiency? What organisms cause pneumonia in this deficiency?
Causes: AIDS, T cell lymphoma, Transplant, DiGeorge’s syndrome
Organisms: Fungi (candida, aspergillus, cryptococcus)
Viral (CMV, HSV)
-Pneumocystis, mycobacteria, listeria
CMV Pneumonia
rare in the immunocompetent but common in T cell def (BMT and lung transplants, less common in AIDs but can co-infect with pneumocystis)
generalized infection (multiple organisms)
Diagnosis-pathology, immunofluorescence, PCR on blood
Therapy: ganciclovir, valganciclovir
What can cause B cell dysfunction or deficiency? What organisms cause pneumonia in this deficiency?
causes: splenectomy, chronic lymphocytic lymphoma, NHL, Myeloma, gamma globulin deficiencies
Organisms:
- strep pneumo
- H flu
- Neisseria
- Klebsiella
- E. coli
- Giardia
