345.3 🏥 內科專科考前版

345.3.1 Mechanistic Deep Dive

345.3.1.1 Bacterial Adherence

  • Pili / fimbriae
  • E. coli FimH (Type 1) + PapG (P fimbriae)
  • Mannose-sensitive (Type 1) inhibited by D-mannose
  • Mannose-resistant (P) involved in pyelonephritis

345.3.1.2 Uropathogenic E. coli (UPEC)

  • Specific virulence factors
  • Biofilm formation
  • Pyelonephritis-associated genes (PAGs)
  • Reservoir in gut

345.3.2 Recent Trials & Updates

345.3.2.1 ALTAR (2022) — Methenamine Hippurate

  • Non-inferior to antibiotics for recurrent UTI prevention
  • ↓ Antibiotic use

345.3.2.2 Uromune Vaccine

  • Sublingual
  • 4-strain
  • Reduces recurrent UTI rates

345.3.2.3 Fosfomycin Trial Updates

  • Single-dose alternative
  • ESBL coverage

345.3.2.4 Cefiderocol for MDR UTI

  • Siderophore cephalosporin
  • Pseudomonas, Acinetobacter, ESBL, CRE

345.3.3 High-Yield Specialist Points

345.3.3.1 Local Antibiogram

  • Check local resistance rates
  • Drives empiric choice
  • E. coli TMP-SMX resistance > 20% → avoid empirically

345.3.3.2 Pyelonephritis + Bacteremia

  • 14 days minimum
  • Source control

345.3.3.3 Renal Abscess

  • Complication of pyelonephritis
  • CT diagnosis
  • Drainage if > 5 cm
  • IV antibiotics

345.3.3.4 Perinephric Abscess

  • Adjacent to kidney
  • Drainage + antibiotics
  • Different from intrarenal

345.3.3.5 Renal Papillary Necrosis

  • DM, sickle cell, analgesic nephropathy
  • Recurrent UTI
  • Hematuria

345.3.3.6 Emphysematous Pyelonephritis

  • Diabetics
  • Klebsiella, E. coli
  • Gas in kidney
  • CT diagnosis
  • Antibiotics + percutaneous drainage; nephrectomy in severe

345.3.3.7 Reflux Nephropathy

  • Pediatric vesicoureteral reflux
  • Recurrent pyelonephritis → scarring
  • VCUG diagnosis
  • Anti-reflux surgery or prophylactic antibiotics

345.3.3.8 Urethritis (STI)

  • N. gonorrhoeae, C. trachomatis, M. genitalium
  • Different treatment than UTI
  • Test for STIs

345.3.3.9 Schistosomiasis Bladder

  • S. haematobium
  • Bladder cancer risk
  • Eosinophiluria

345.3.3.10 Renal TB

  • Sterile pyuria
  • Bladder lesions
  • Diagnosis with PCR + culture

345.3.3.11 Candiduria

  • Catheter-associated common
  • Treat only if symptomatic
  • Fluconazole (sensitive)
  • Echinocandin if resistant

345.3.3.13 UTI in Spinal Cord Injury

  • Frequent
  • Asymptomatic bacteriuria common (don’t treat)
  • Indwelling vs intermittent catheter

345.3.3.14 Pregnant Pyelonephritis

  • Severe; hospitalization
  • IV ceftriaxone
  • Risk of preterm labor
  • Sepsis risk

345.3.3.15 Pediatric UTI

  • Often febrile, vague
  • VCUG if recurrent or first if < 2 years
  • Imaging for stones, reflux

345.3.3.16 UTI in Renal Transplant

  • More common
  • Higher complications
  • Trim-sulfa prophylaxis common (also for PCP)
  • Watch BK virus

345.3.4 Pearls

  • E. coli most common (75-95% uncomplicated)
  • Nitrofurantoin first-line for uncomplicated cystitis
  • Pyelonephritis: ciprofloxacin outpatient; ceftriaxone IV inpatient
  • Asymptomatic bacteriuria: treat only pregnancy + pre-procedure
  • Recurrent UTI: postcoital prophylaxis, vaginal estrogen, methenamine, vaccines
  • Acute prostatitis: fluoroquinolone × 4-6 weeks
  • CP/CPPS: multidisciplinary
  • MDR: cefiderocol + ceftaz-avibactam + meropenem-vaborbactam emerging
  • Pregnancy: nitrofurantoin (not term), cephalexin, fosfomycin