A 5-year-old boy with active nephrotic syndrome develops fever, diffuse abdominal pain, and guarding. Ascitic fluid shows 450 neutrophils/mm3. Which is the most common causative organism of this complication?

• A Streptococcus pneumoniae ✓
• B Staphylococcus epidermidis
• C Pseudomonas aeruginosa
• D Anaerobic Bacteroides species

Explanation

Spontaneous bacterial peritonitis is a recognized serious complication of childhood nephrotic syndrome because ascitic fluid supports bacterial growth while serum IgG and complement factor A are lost in urine. Streptococcus pneumoniae is classically the most common isolate, followed by E. coli. Skin commensals such as S. epidermidis cause catheter related infections, and anaerobes are typical of secondary peritonitis from bowel perforation, not spontaneous ascitic infection.

Reference: Nelson Textbook of Pediatrics, 21st ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

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