Relapse of minimal change disease following infection with the 2009 pandemic influenza (H1N1) virus.

We report a case of relapse of minimal change disease following infection with the influenza A (H1N1) virus responsible for the 2009 pandemic. A 22-year-old man who had been diagnosed with minimal change disease presented with systemic edema. He had achieved complete remission with an oral steroid (prednisolone 1 mg/kg/day) by the 17th day of administration. On the 27th day of prednisolone administration, he presented with a new onset of generalized edema after several days of productive coughing. His urine showed proteinuria (4+) with a protein/creatinine ratio (PCR) of 2852.1 mg/g. His nasal swab sample was positive for the 2009 pandemic influenza (H1N1) virus by real-time reverse-transcriptase polymerase chain reaction (RT-PCR). He received oseltamivir (150 mg/day) for 5 days. A day after completing the oseltamivir therapy, his proteinuria returned to a normal range; urinalysis was negative for protein with PCR 79.2 mg/g. One month later, the patient remained normal with no proteinuria.