Incidence of Febrile Urinary Tract Infection According to Clinical Characteristics in Patients with Congenital Hydronephrosis and Hydronephrotic Patients Diagnosed at First Febrile Urinary Tract Infection

PURPOSE: The aim of this study was to evaluate the incidence of febrile urinary tract infection (UTI) according to clinical characteristics in patients with congenital hydronephrosis (CH) and hydronephrotic patients first diagnosed with hydronephrosis during treatment of febrile UTII. METHODS: In this study, 200 patients with congenital hydronephrosis were enrolled in group 1 and 252 patients first diagnosed with hydronephrosis during treatment of febrile UTI were enrolled in group 2. We counted the episodes of UTI in the two groups according to clinical characteristics, the presence of VUR, type of feeding, and clinical outcomes since 2000. And we compared those results between the two groups. and compared two groups as well. RESULTS: The incidence of recurrent UTI was 10%, 0.028 per person-year in group 1 and 16.7%, 0.051 per person-year in group 2, respectively (P <0.05). Group 2 had more VUR (3% vs. 27%, P <0.05) and higher incidence of UTI than group 1. The incidence of UTI in patients with CH of Society of Fetal Urology (SFU) grade 4 or grade 4-5 VUR was 80% and 44.4%, respectively. No significant differences were found in incidence of UTI between BMF (breast milk feeding) and artificial milk feeding group in both groups (P 1= 0.274, P 2=0.4). The time of resolution of CH had no correlation with either number of UTI episodes or the presence of VUR. CONCLUSION: The overall incidence of UTI is low in patients with CH as well as patients patients first diagnosed with hydronephrosis during treatment of febrile UTI except patients with SFU grade 4 or grade 4-5 VUR. BMF has no protective effect against UTI.

Hypokalemia-induced Polyuria with Nocturia after Intravenous Methylprednisolone Pulse Therapy in a Henoch-Schonlein Purpura Nephritis Patient

Patients with moderate to severe degrees of Henoch-Schonlein purpura (HSP) nephritis receive high-dose intravenous methylprednisolone pulse therapy (IMPT). Although the regimen is generally safe and effective, various complications occasionally develop. administration of excessive corticosteroid can induce urinary potassium wasting leading to hypokalemia. Polyuria, one of the complications of hypokalemia, is related to both increased thirst and mild nephrogenic diabetes insipidus. And hypokalemia itself also impairs the maximal renal urinary concentration ability. Although polyuria or nocturia after IMPT is not common, it is correctable immediately by oral potassium supplementation. Therefore, during IMPT, careful history taking of nocturia as well as monitoring urine volume, serum and urine potassium level at regular follow-up are necessary because even mild hypokalemia can provoke urine concentrating ability defect. We experienced a case of 11 year-old boy with HSP nephritis who suffered from hypokalemia-induced polyuria with nocturia right after IMPT.

Significant Proteinuria Caused by Posterior Nutcracker Phenomenon

Posterior nutcracker phenomenon (PNP) was found to be the cause of significant proteinuria in a 10-year-old female. PNP was documented by Doppler ultrasonography and abdominal 3D CT as a cause of her proteinuria. Despite treatment with ACE inhibitor for several months, her persistent and progressive proteinuria lead us to perform a left renal biopsy, which revealed no significant finding except for focal effacement of foot processes. We speculate that nutcracker phenomenon can induce not only orthostatic proteinuria but also significant proteinuria by focal effacement of foot processes.