title: Two cases of renal hypouricemia with nephrolithiasis.
abstract: We treated two cases of renal hypouricemia with nephrolithiasis. The serum uric acid level of the first patient was 1.5 mg/dl, and the ratio of uric acid clearance to creatinine clearance (CUA/Ccr) was 75.7%. In the benzbromarone (BZB) suppression test, CUA/Ccr was increased from 60.4% to 130.0%, but was not decreased in response to the pyrazinamide (PZA) suppression test. This patient was considered to have a presecretory reabsorptive urate transportation defect. His condition was also associated with IgA nephropathy. The serum uric acid level in the second patient was 1.0 mg/dl and CUA/Ccr was 56.0%. Neither PZA nor BZB had a significant effect on CUA/Ccr. He was considered to have a subtotal uric acid transportation defect. Both patients were incidentally found to have nephrolithiasis. The second patient had abnormal maximum tubular secretory capacity for para-aminohippurate (PAH) (TmPAH), and was found to have two kinds of proximal tubular abnormalities related to uric acid and PAH.
authors.affiliation: First Department of Internal Medicine, Okayama University School of Medicine.
authors.forename: S
authors.initials: S
authors.lastname: Hirasaki
authors.forename: N
authors.initials: N
authors.lastname: Koide
authors.forename: K
authors.initials: K
authors.lastname: Fujita
authors.forename: H
authors.initials: H
authors.lastname: Ogawa
authors.forename: T
authors.initials: T
authors.lastname: Tsuji
mesh_terms: D000328:Adult; D001553:Benzbromarone; D003404:Creatinine / Q000097:blood; D006801:Humans; D007669:Kidney Calculi / Q000150:complications* / Q000378:metabolism; D007684:Kidney Tubules / Q000378:metabolism; D008297:Male; D008875:Middle Aged; D011718:Pyrazinamide; D014527:Uric Acid / Q000097:blood* / Q000652:urine; D014528:Uricosuric Agents
chemical_list: D014528:Uricosuric Agents; D014527:Uric Acid; D011718:Pyrazinamide; D001553:Benzbromarone; D003404:Creatinine