Infectious Disease Pharmacology — Key Flashcards (UTI, ENT, CAP, TB)

Flashcards cover key pharmacologic and management concepts for UTIs, ENT infections, CAP, and latent TB based on the notes.

Nitrite positive urine dipstick

Urine dipstick finding most indicative of a urinary tract infection (UTI).

First-line therapies for acute uncomplicated cystitis

Nitrofurantoin 100 mg twice daily for 5 days, or TMP-SMX for 3 days, or Fosfomycin as a single 3 g dose.

Moxifloxacin

Fluoroquinolone not recommended for empiric cystitis due to poor renal excretion and urinary concentration.

Empiric therapy for acute pyelonephritis

Fluoroquinolones (ciprofloxacin, levofloxacin) or TMP-SMX for 7–14 days.

Postcoital prophylaxis for recurrent UTIs

Prophylaxis after intercourse: TMP-SMX 1/2 tablet or nitrofurantoin 50 mg after sex.

Nitrofurantoin in late pregnancy

Avoid after 37 weeks due to risk of hemolytic anemia in the newborn.

TMP-SMX in late pregnancy

Avoid during the 3rd trimester due to risk of kernicterus.

Antibiotic class with highest collateral damage in UTI therapy

Fluoroquinolones.

First-line treatment for acute bacterial rhinosinusitis

Amoxicillin/clavulanate.

Definition of treatment failure in sinusitis

Symptoms not improving after 10 days or worsening after initial improvement (double sickening).

First-line therapy for Group A streptococcal pharyngitis

Penicillin or amoxicillin for 10 days.

RADT-negative testing in children

Negative RADT should always be backed up with culture due to rheumatic fever risk.

First-line therapy for acute otitis media in children

Amoxicillin 80–90 mg/kg/day divided BID.

Observation without antibiotics in otitis media

Consider in children ≥2 years with bilateral AOM without otorrhea, or unilateral AOM without otorrhea.

Conjunctivitis treatment in high-risk patients

Topical antibiotics (fluoroquinolones, azithromycin, or gentamicin).

CAP without comorbidities—first-line agents

Amoxicillin, doxycycline, or macrolide (if resistance <25%).

CAP with comorbidities—empiric therapy

β-lactam plus macrolide/doxycycline, or respiratory fluoroquinolone monotherapy.

Minimum duration of CAP therapy

5 days, provided the patient is clinically stable and afebrile for 48–72 hours.

Tetracyclines in children <8 for CAP

Tetracyclines are generally contraindicated in children <8 (doxycycline may be used short-term in select cases).

Latent TB infection treatment regimens

INH + rifapentine weekly for 12 weeks; or rifampin for 4 months; or INH + rifampin for 3 months.