Incidence in children: 1–3 per 100,000; mortality now <10% with modern imaging and drainage.
Predisposing conditions:
Pre-existing biliary tract disease (e.g., biliary atresia post-portoenterostomy)
Immunocompromise (oncology, transplant, chronic steroids)
Intra-abdominal infection or trauma (appendicitis, IBD perforation)
Umbilical venous catheterization in neonates
Hematogenous seeding via portal vein bacteremia from gut or peritoneal infections
Contiguous spread from adjacent organs
Polymicrobial in 60–80% of cases
Common isolates:
Streptococcus species (especially anginosus group)
Staphylococcus aureus (incl. MRSA)
Enteric gram-negative rods (E. coli, Klebsiella)
Anaerobes (Bacteroides spp., Fusobacterium)
Fever, chills, malaise
Right upper quadrant (RUQ) pain or tenderness
Hepatomegaly in 50%
Occasionally referred shoulder pain
Mild–moderate elevations in AST/ALT
↑ Alkaline phosphatase
Jaundice if biliary obstruction
Blood cultures positive in ~50%
Ultrasound: first-line—detects fluid collections ≥1–2 cm
Contrast CT: gold standard—delineates size, number, loculations, adjacent structures
MRI: sensitive for small or multiloculated lesions
Empiric antibiotics (begin immediately):
Third-generation cephalosporin (ceftriaxone) plus metronidazole
Or piperacillin-tazobactam
Add vancomycin if MRSA risk
Drainage:
Percutaneous catheter drainage for abscesses ≥3 cm or multiloculated
Needle aspiration may suffice for single, small (<3 cm) lesions
Surgical drainage:
Indicated for multiple, complex, or refractory abscesses
Risks: peritonitis, fistula, hemorrhage, hepatic laceration
Duration: 4–6 weeks of total therapy (2–3 weeks IV, then oral step-down)
Particularly common in infants/children post–portoenterostomy for biliary atresia (40–50% risk within 3 months)
Other risk factors: choledochal cysts, choledocholithiasis, Caroli disease, sphincter of Oddi dysfunction
Bacterial ascent from duodenum or portal venous seeding into an obstructed biliary tree
Predominantly enteric gram-negatives (Escherichia coli most common)
Often polymicrobial, may include enterococci and anaerobes
Charcot triad: fever, RUQ pain, jaundice (seen in 50–75%)
Possible progression to Reynolds pentad with hypotension and altered mental status
Leukocytosis
↑ Serum bilirubin, alkaline phosphatase, AST/ALT above baseline
Blood cultures positive in ~50%
Ultrasound: bile duct dilation, gallstones, sludge
CT/MRCP: evaluate for strictures, abscess, or biliary dilation
Empiric antibiotics (10–14 days):
Third-generation cephalosporin (ceftriaxone) plus metronidazole
Or piperacillin-tazobactam
Avoid aminoglycosides to reduce nephrotoxicity risk in cholestatic patients
Biliary decompression:
Urgent ERCP or percutaneous transhepatic cholangiography if no clinical improvement in 48 hours
Recurrent episodes may cause chronic cholestasis and secondary biliary cirrhosis
Extension of pelvic inflammatory infection—Neisseria gonorrhoeae or Chlamydia trachomatis—via hematogenous spread or peritoneal surfaces
Sudden, severe RUQ pain often exacerbated by respiration
May hear a friction “rub” over right anterior chest wall
Leukocytosis, ↑ CRP/ESR; liver enzymes usually normal
CT: hyperemia or enhancement of anterior liver capsule
Laparoscopy: “violin-string” adhesions between liver capsule and diaphragm or abdominal wall
Cervical/urethral/rectal swabs: N. gonorrhoeae or C. trachomatis
Ceftriaxone 25–50 mg/kg IM (max 250 mg) once
Plus doxycycline 2 mg/kg PO twice daily (max 100 mg BID) for 7 days
Presentation: miliary or localized hepatic TB—fever, weight loss, hepatomegaly; possible biliary obstruction from periportal adenopathy
Imaging: calcified granulomas on plain film or CT; miliary nodularity
Diagnosis: culture or PCR from gastric aspirate, sputum, or liver biopsy
Histology: caseating granulomas with acid-fast bacilli
Treatment: standard RIPE regimen—2 months of isoniazid, rifampin, pyrazinamide, ethambutol, then 4 months of isoniazid + rifampin
Occurs primarily in HIV-infected or profoundly immunosuppressed children
Diagnosis: positive blood, sputum, or fecal cultures; histology shows foamy macrophages with AFB
Treatment: clarithromycin (15 mg/kg/day) + ethambutol (15 mg/kg/dose three times weekly); add rifabutin for severe disease
Leptospira interrogans—spirochete shed in urine of infected animals (rodents, livestock)
Human infection via contact with contaminated water or soil
Biphasic illness:
Leptospiremic phase—fever, headache, myalgia, conjunctivitis, rash
Immune phase—jaundice, renal failure, hemorrhage (Weil disease)
↑ AST/ALT, bilirubin
Leukocytosis, thrombocytopenia, proteinuria, coagulopathy
Microscopic agglutination test (MAT) serology
Culture of blood/CSF in first 7–10 days; urine culture up to 3 weeks
IV penicillin G (100,000–150,000 U/kg/day divided every 6 hours) for 7 days
Doxycycline (2 mg/kg/dose BID) alternative in older children
Borrelia burgdorferi transmitted by Ixodes ticks
Classic erythema migrans rash; systemic: fever, headache, arthralgias, lymphadenopathy; mild hepatitis
↑ AST/ALT (mild)
Two-step serology: ELISA followed by Western blot
Doxycycline 4 mg/kg/day in two divided doses (max 100 mg BID) for 14–21 days (children ≥8 years)
Amoxicillin 50 mg/kg/day divided TID for children <8 years
Regional lymphadenitis; fever, malaise; hepatosplenic involvement in disseminated disease (peliosis hepatis)
Ultrasound/CT: multiple small hypodense lesions in liver and spleen
Biopsy: necrotizing granulomatous hepatitis with stellate abscesses
Serology (IFA or ELISA) for B. henselae IgG/IgM
Mild disease: azithromycin 10 mg/kg day 1, then 5 mg/kg daily on days 2–5
Hepatosplenic/disseminated: azithromycin plus rifampin (20 mg/kg/day in divided doses) for 2–4 weeks
Salmonella enterica serotypes Typhi and Paratyphi A/B/C
Imported cases in U.S. travelers from endemic regions
Stepwise fever, headache, abdominal pain; hepatosplenomegaly; potential complications: intestinal perforation, encephalopathy, pneumonia
Mild–moderate ↑ AST/ALT
Blood cultures positive in 40–80% during first week; bone marrow culture more sensitive
Ceftriaxone 50 mg/kg/day IV once daily (max 2 g) for 7–14 days
Azithromycin 20 mg/kg/day PO (max 1 g/day) for 7 days in uncomplicated, fully susceptible cases
Tailor to regional resistance patterns
Brucella melitensis, B. abortus, B. suis—zoonotic from unpasteurized dairy or animal contact
Undulating fever, sweats, malaise, weight loss, arthralgia, back pain; 25% with hepatosplenomegaly
↑ ESR/CRP; mild ↑ AST/ALT
Blood or bone marrow culture (gold standard); PCR or serology (SAT, ELISA)
Children ≥8 years: doxycycline 4 mg/kg/day PO in two divided doses × 6 weeks plus rifampin 15–20 mg/kg/day PO × 6 weeks
Children <8 years: TMP-SMX (8 mg TMP/kg/day PO in divided doses) plus rifampin for 6 weeks
Early recognition and imaging (US/CT) are critical for diagnosis.
Empiric antibiotic regimens must cover likely pathogens—polymicrobial in abscess and cholangitis.
Percutaneous drainage has revolutionized abscess management; surgery reserved for refractory cases.
Cholangitis in postoperative biliary atresia often requires both antibiotics and endoscopic/radiologic decompression.
Uncommon infections (e.g., leptospirosis, Bartonella) must be considered in the appropriate epidemiologic context.
Coordination with pediatric infectious diseases, interventional radiology, and surgery optimizes outcomes.