Which investigation is essential to guide treatment for suspected PD-related peritonitis?

• A. Effluent culture.
• B. Urinalysis only.
• C. Renal ultrasound.
• D. Serum creatinine.

Answer: (A)

Identifying the exact infectious organism in suspected PD-related peritonitis guides which antibiotics to use. The dialysate effluent culture reveals the pathogen and its antibiotic sensitivities, allowing you to tailor therapy rather than rely on broad, one-size-fits-all treatment. In practice, you collect effluent for culture at the start and begin empiric intraperitoneal antibiotics right away; once culture results return, you can narrow or adjust the regimen and decide on further steps like catheter management if needed. Urinalysis alone doesn’t inform peritoneal infection treatment, and renal ultrasound or serum creatinine don’t determine the antimicrobial plan for peritonitis, though they may have other uses in care.