부산대학교 도서관

There have been numerous reports of pseudo-hypoaldosteronism type III (PHA III) associated with upper urinary tract infections (uUTIs) and/or urinary tract abnormalities occurring in infants younger than 90 days of age. This transient distal tubular dysfunction is not usually missed because it mostly presents as life-threatening events including severe hyponatremia and hyperkalemia. In this case, we experienced a simple upper urinary tract infection complicated by transient Fanconi syndrome (FS), without PHA III or other distal tubular lesions. A 28-day-old baby girl with 21 trisomy had her first upper urinary tract infection without urinary tract abnormalities, as determined by imaging studies. Despite rapid resolution of fever with appropriate antimicrobial therapy, the baby continued to be limp and weak. Further examination confirmed a diagnosis of FS with no evidence of distal tubular dysfunction. Short-term alkaline and potassium infusion promptly improved her general condition, but it took two months to achieve complete biochemical resolution. uUTIs in young infants may be complicated by transient renal tubular dysfunction limited to proximal site and may last for weeks after control of the underlying infection has been achieved. Secondary transient FS should be considered when poor general activities persist following uUTIs in young infants even if their fever subsides promptly after use of appropriate antibiotic agents. Careful follow-up of patient recovery is crucial.