title: Focal bacterial nephritis without pyuria in a boy presenting with high urinary β2-MG and NAG levels.
abstract: Acute focal bacterial nephritis (AFBN) is a localized bacterial infection of the kidney presenting as an inflammatory mass without frank abscess formation. We report a case of acute focal bacterial nephritis without pyuria in a five-month-old boy presenting with high urinary β2-microglobulin (β2-MG) and N-Acetyl-β-(D)-Glucosaminidase (NAG) levels. The infant initially presented with high-grade fever, and plain computed tomography (CT) showed a nearly isodense mass, and contrast-enhanced abdominal CT showed a wedge-shaped hypodense lesion. Enterococcus was detected in the subsequent urine culture. A diagnosis of AFBN was made on the basis of his high inflammatory reaction, contrast-enhanced abdominal CT findings and high urinary β2-MG and NAG levels. He was treated with Ceftriaxone and subsequent improvement in inflammatory reaction and contrast-enhanced CT findings were observed. Voiding cystourethrogram (VCUG) showed a grade V right VUR. This case suggests that urinary β2-MG and NAG levels may be useful additional markers for the diagnosis of AFBN without pyuria.
authors.affiliation: Department of Pediatrics, Fukushima Medical University School of Medicine.
authors.forename: Hitomi
authors.initials: H
authors.lastname: Sekine
authors.forename: Yukihiko
authors.initials: Y
authors.lastname: Kawasaki
authors.forename: Shinichiro
authors.initials: S
authors.lastname: Ohara
authors.forename: Kazuhide
authors.initials: K
authors.lastname: Suyama
authors.forename: Mitsuaki
authors.initials: M
authors.lastname: Hosoya
mesh_terms: D000118:Acetylglucosaminidase / Q000652:urine; D000900:Anti-Bacterial Agents / Q000627:therapeutic use; D015415:Biomarkers / Q000652:urine; D002443:Ceftriaxone / Q000627:therapeutic use; D016983:Enterococcus; D005490:Focal Infection / Q000000981:diagnostic imaging / Q000188:drug therapy / Q000652:urine*; D016908:Gram-Positive Bacterial Infections / Q000000981:diagnostic imaging / Q000188:drug therapy / Q000652:urine*; D006801:Humans; D007223:Infant; D008297:Male; D009393:Nephritis / Q000000981:diagnostic imaging / Q000188:drug therapy / Q000652:urine*; D011859:Radiography; D001613:beta 2-Microglobulin / Q000652:urine
chemical_list: D000900:Anti-Bacterial Agents; D015415:Biomarkers; D001613:beta 2-Microglobulin; D002443:Ceftriaxone; D000118:Acetylglucosaminidase