Infectious Diseases PREmidterm edit Flashcards
acute bronchitis definition + common causes
-Self-limited inflammation of large airways -> cough without pneumonia
-VIRUS MC:
-Influenza A and B
-Parainfluenza
-Coronavirus (types 1-3)
-Rhinovirus
-RSV
pathophysiology acute bronchitis
Inflammatory response to infections of bronchial epithelium
-inflamed areas of bronchi and tracheal mucosa thicken
- purulent sptum: from sloughed off tracheobronchial epithelium and inflammatory cells
acute bronchitis symptoms
Sx:
Cough for over 5 days
+/- purulentputum (50%)**
- >5 days = acute bronchitis NOT URI
- NO FEVER, tachycardia, tachypnea -> r/o pneumonia
Signs:
- rhonchi**
- normal vitals
+/- wheezing
PFTs: acute bronchitis
-generally not indicated
-may become abnormal
-significant reductions in FEV1 -> obstructive pattern
-bronchial hyperreactivity
acute bronchitis dx
PHYSICAL EXAM!
-cough WITHOUT fever, tachycardia and tachypnea suggests bronchitis, rather than pneumonia
-normal vital signs
- no rales and egophony
Chest x-ray:
- only if cant distinguish by physical exam
Acute bronchitis rapid tests
-Rapid dx tests for several pathogens linked to acute bronchitis -> COVID-19, Influenza, RSV
Rapid tests should be used if:
-Suspected organism is treatable
-Infection circulating in the community
-pt has suggestive symptoms or signs
treatment of acute bronchitis
Antimicrobial agents are NOT recommended in most acute bronchitis **
Supportive Care*
- If cough is 20+ days, may give inhaled or oral corticosteroids
Antimicrobial therapy only if:
- Influenza agents
- Pertussis
- COVID-19
influenza symptoms
ABRUPT onset of fever, headache, myalgia*
arthralgias, malaise
- watching tv and all of sudden feel awful
influenza PE
Physical Exam: not that bad
- Feeling of hot and flushed
- Oropharyngeal hyperemia
- Mild cervical lymphadenopathy
- Respiratory exam unremarkable
influenza labs, xray and dx
Labs = not helpful
-leukopenia
Xray = normal
Diagnostic Test: RT-PCR
- Rapid tests for influenza antigens are widely available
- RT-PCR is most sensitive and specific*
influenza maincomplication and risk group
Pneumonia (MC)
-High risk groups:
-Cardiovascular or pulmonary ds
-Diabetes mellitus, renal disease, hemoglobinopathy, or immunosuppression
-Nursing homes or chronic care facilities
-Over age 50, pregnant, young kids
primary viral pneumonia description + sx
Occurs when symptoms persist and worsen **
- INTERSTITIAL tissue
Sx:
-High fever, dyspnea, and progression to cyanosis can be seen
primary viral pneumonia vs secondary pneumonia xray
Primary: INTERSTITIAL, diffuse everywhere inflitrates
Secondary:
- Lobar/ALVEOLAR Infiltrates
- consolidations
secondary bacterial pneumonia
Relapse, get a bacterial infection while recovering from virus**
- purulent sputum
- MC: Strep pneumoniae
- Most severe: Staph aureus
influenza complications
Reye syndrome**- assoc with kids and aspirin use -> dont give aspirin to kids -> encephalopathy
-flu + aspirin = assoc with reye syndrome
prevention of influenza + prophylax
Influenza vaccine provides 85% efficacy immunity for few months - 1 year
- Vaccine is HIGHLY RECOMMENDED for > 6 months
- Takes 2 weeks after shot for immunity
Chemoprophylaxis
- Oseltamivir, Zanamivir, Baloxavir
- Reduces attack rate if taken within 48 hours after exposure
influenza treatment
Supportive Care with Hydration!
- Analgesics (ASA is not recommended, risk of Reye Syndrome)
Neuraminidase inhibitors: within 48h of sx
-Baloxavir (QD*)
-Oseltamivir (BID x 5 days) -> tamaflu
-Zanamivir (two 5mg inhalations twice daily for 5 days) - cant give to pts with asthma
who to treat: influenza
-Illness requiring hospitalization
-Progressive, severe, or complicated illness, regardless of previous health or vaccination status
-High risk pts: children under 2, over 65, comorbid ds, immunosurpressed, ASA users
bordetella pertussis infection description and is pertussis lifelong immunity after vaccination
Transmission: respiratory droplets
-Incubation period: 7–21 days
Most cases (50%) are those < 2 yo
vaccine or past disease does not give lasting immunity to pertussis**
-Adults are important reservoir (waning immunization)
bordetella pertussis stages
Sx last about 6 weeks
-1. Catarrhal stage- feels like a respiratory infection
-2. Paroxysmal stage- whooping cough
-3. Convalescent stage- recovery
bordetella pertussis: Catarrhal stage
-7-10 days
-insidious/gradual onset
-Lacrimation, sneezing, coryza, anorexia, malaise, and hacking NIGHT cough that becomes DIURNAL (during day) -> like URI
bordetella pertussis: paroxysmal stage
-1-6 wks but up to 10
-posttussive emesis & fatigue
-“whoop”: cough
bordetella pertussis: convalescent stage: 1-3 weeks
-Decrease in frequency and severity of paroxysms of cough
bordetella pertussis labs and CXR
WBC: 15,000–20,000/mcL
CXR: nonspecific
-Peribronchial cuffing (walls of bronchi are edematous -> donut sign), perihilar infiltrates, interstitial edema, or atelectasis
-Pulmonary consolidation (20 %)
-primary or Secondary bacterial pneumonia
bordetella pertussis complications
-Pneumonia (primary and secondary)
pertussis diagnosis
-Diagnosis: combinations of diagnostic tests to identify persons with pertussis, based upon the duration of cough
- Wk 0-2: culture + PCR
- Wk 2-4: PCR + serology
- Wk 4+: serology
pertussis prevention
DTaP vaccine!!
-Booster vaccination: for adolescents/adults
Post exposure prophylaxis: azithromycin
tx and post exposure tx for pertussis
-adults - ZPAC- azithromycin
