López M M, Castillo L A, Chávez J B, Ramones C
Equipex SA, Miami FL 33102-0010, USA.
Pediatr Nephrol. 1999 Jun;13(5):433-7. doi: 10.1007/s004670050635.
Recurrent urinary tract infection (UTI) has not been widely recognized as a clinical manifestation of hypercalciuria in children. We studied 59 children with two or more episodes of UTI, a normal urinary tract, and with hypercalciuria. Clinical manifestations were fever, dysuria, straining with micturition, hematuria, polyuria, abdominal pain, and failure to thrive. Urinary calcium/creatinine ratio was 0.36+/-0.15 mg/mg. Renal function studies included serum bicarbonate (21+/-3 mmol/l), urinary/blood PCO2 difference (11+/-11 mmHg), urinary net acid excretion (63+/-3 micromol/min per 1.73 m2), uric acid fractional excretion (13%+/-12%), and maximal urinary osmolality (920+/-236 mosmol/kg). Treatment included promotion of fluid intake, avoiding excessive salt and protein, and keeping dietary calcium between 900 and 1,200 mg/day. Potassium citrate or hydrochlorothiazide were indicated if hypercalciuria persisted. With this treatment, in 95% of the children, no further episodes of UTI occurred once normocalciuria was achieved. It is possible that hypercalciuria may play a predisposing role for recurrent UTI in children by promoting the formation of microcrystals which damage the uroepithelium. We advocate the investigation of urinary calcium excretion in children with recurrent UTI and a normal urinary tract.
复发性尿路感染（UTI）尚未被广泛认为是儿童高钙尿症的一种临床表现。我们研究了59名患有两次或更多次UTI、尿路正常且有高钙尿症的儿童。临床表现为发热、排尿困难、排尿时用力、血尿、多尿、腹痛和发育不良。尿钙/肌酐比值为0.36±0.15mg/mg。肾功能研究包括血清碳酸氢盐（21±3mmol/L）、尿/血PCO2差值（11±11mmHg）、尿净酸排泄（63±3μmol/min每1.73m2）、尿酸排泄分数（13%±12%）和最大尿渗透压（920±236mosmol/kg）。治疗包括增加液体摄入量、避免过量的盐和蛋白质，并使饮食钙摄入量保持在每天900至1200mg之间。如果高钙尿症持续存在，则使用柠檬酸钾或氢氯噻嗪。通过这种治疗，95%的儿童在实现正常钙尿症后未再发生UTI。高钙尿症可能通过促进损害尿路上皮的微晶形成，在儿童复发性UTI中起易感作用。我们主张对患有复发性UTI且尿路正常的儿童进行尿钙排泄调查。
