Active surveillance for antenatally detected ureteroceles: Predictors of success.

INTRODUCTION: Historically, ureteroceles were surgically treated, as patients were diagnosed after developing symptoms. However, with the advance of fetal medicine, antenatal detection has provided an opportunity to look at the natural history of ureteroceles. OBJECTIVES: With data derived from a retrospective chart review of patients with ureteroceles that were detected antenatally, the current study aimed to determine which group of children would be at risk for failure on active surveillance. It was hypothesized that single system ureteroceles (SSU) and male patients with duplex system ureteroceles (DSU) would be ideal for observation. METHODS: Outcomes were assessed by descriptive statistics. Kaplan-Meier curves were utilized to estimate median duration on active surveillance in both single and duplex cohorts. Breakthrough febrile urinary tract infection (fUTI) and surgery were determined by Cox regression in the duplex system cohort. Surgery was considered surveillance failure. RESULTS: A total of 102 patients (64 females/38 males) met the criteria: 78 (76.5%) had DSU and 24 (23.5%) SSU. The overall median observation was 1.2 years (range 0.7-3.1). Follow-up ranged from 0.3 to 11.7 years for SSU, and from 0.02 to 17.3 years for DSU. The predictors of failure of active surveillance (AS) in DSU (surgical intervention) were male gender (HR 1.8, 1.0-3.3, P = 0.037), or fUTI (HR 3.1, 1.7-5.8, P = 0.002). Predictors of fUTI were contralateral hydroureter or ipsilateral hydronephrosis ± hydroureter (OR 9.5, 1.2-71.7, P = 0.028). Interestingly, vesicoureteral reflux (VUR) was not a predictor of fUTI. The SSU patients were ideal for AS, while in DSU, surveillance was successful in 30% of patients who were primarily females without contralateral hydroureter or ipsilateral hydronephrosis ± hydroureter. However, in contradiction to the hypothesis, males were at higher risk for surgical intervention in the DSU cohort. CONCLUSION: Active surveillance is an option for patients with antenatally detected ureteroceles, but careful long term follow up is mandatory. Parents should be advised that surgical intervention may still be necessary, particularly in males with DSU.

The microbial metabolism of Cl compounds. The stoicheiometry of respiration-driven proton translocation in Pseudomonas AM1 and in a mutant lacking cytochrome c.

This paper clarifies the role of cytochrome c in Pseudomonas AM1 by measuring the stoicheiometry of proton translocation driven by respiration of endogenous or added substrates in wild-type bacteria and in a mutant lacking cytochrome c (mutant PCT76). The maximum -->H(+)/O ratio (protons translocated out of the bacteria per atom of oxygen consumed during respiration) was about 4 and, except when respiration was markedly affected, this ratio was similar in mutant and wild-type bacteria. The -->H(+)/O ratios were unaltered when the usual oxidase (cytochrome a(3)) was inhibited by 300mum-KCN and respiration involved the single cytochrome b functioning as an alternative oxidase. Ratios measured in cells respiring endogenous substrate and in cells loaded with malate or 3-hydroxybutyrate suggest that there are two proton-translocating segments operating during the oxidation of NADH. By contrast, during oxidation of formaldehyde or methylamine only one pair of protons is translocated. Proton translocation could not be measured with methanol as substrate, because its oxidation was inhibited (90-95%) by 5mm-KSCN. It is tentatively proposed that the electron-transport chain for NADH oxidation in Pseudomonas AM1 is arranged such that the NADH-ubiquinone oxidoreductase forms one proton-translocating segment and the second segment consists of ubiquinone and cytochromes b and a/a(3). The cytochrome c appears to be essential only for respiration and proton translocation from methanol (and possibly from methylamine); there is no conclusive evidence that cytochrome c ever mediates between cytochromes b and a/a(3) in Pseudomonas AM1.