Acute Lobar Nephronia with Negative Urine Cultures Presenting with a Palpable Painful Mass: A Case Report

Children with severe urinary tract infections such as acute pyelonephritis and acute lobar nephronia, presenting with a fever and abdominal mass are not common. Such cases are generally mistaken as intra-abdominal abscess. Without early identification, aggressive antibiotic treatment, or even surgical drainage, acute lobar nephronia may progress to renal abscess or emphysematous pyelonephritis. Here, we report the case of a female aged 11 years and 7 months who presented with fever and a palpable mass located in the right lower quadrant. Computed tomography confirmed a diagnosis of acute lobar nephronia; however, the urine culture was negative. Treatment with intensive antibiotics (ceftriaxone and metronidazole) was adequate, and drainage was not required. With early diagnosis, such patients can be safely treated medically.