RENAL PROBLEMS AND CRITICAL CARE Solution 8

The most likely diagnosis here, given the temporal relationship between the antibiotics, the rash and the renal failure, is that penicillin is responsible for both of the injuries. The diagnosis is acute interstitial nephritis; confirmed by looking for eosinophils in the urine. I would change her to a non beta-lactam antibiotic (such as vancomycin), and look for a history of penicillin allergy. If the patients renal failure does not respove, i.e. she remains anuric, she develops uremic symptoms, or becomes hyperkalemic or acidotic, I would dialyze her.

The antibiotics are stopped. On chart review the patient gave a history of penicillin allergy on her previous admission (for tubal surgery). Within 24 hours, the rash is beginning to resolve, and  urinary flow restarts. Seven days later, the patient’s serum creatinine is 0.8.