Prognostic factors in Saudi children with posterior urethral valves

Abstract

Posterior urethral valves (PUV) account for a sizeable proportion of children with chronic renal failure. Several criteria have been identified as predictive of future renal function in children with PUV. We compared the presenting features and initial treatment in two groups of Saudi children treated for PUV, with the aim of identifying any factors that might account for the differences observed in their renal function. One group (group A, 19 patients) had a serum creatinine of 80 micromol/l or less at follow-up and the other (group B, 13 patients) had higher levels. There was no significant difference in age or weight at presentation, incidence and severity of reflux, urinary tract infection, or type of primary treatment (valve ablation versus vesicostomy) between the two groups. However, after 5-7 days of catheter drainage, the mean serum creatinine level was 88+/-62 micromol/l for patients in group A compared with 172+/-77 micromol/l for those in group B (P<0.0001). This difference was highly significant. Linear regression analysis of post-drainage creatinine and serum creatinine at last follow-up showed a correlation coefficient of 0.7171 (P<0.0001). Hence the serum creatinine level after catheter drainage correlated strongly with renal function during short-term follow-up of Saudi children with PUV. This might help in the selection of the optimal initial therapy and provide some basis for prognostication.

Validation of initial serum creatinine as a predictive factor for development of end stage renal disease in posterior urethral valves

“…On the contrary, the present findings, as well as those of other investigators suggest no significant association between these variables and the subsequent renal function outcome. 4,5,10,18 Dissimilar study designs among these reports are probably the most likely cause for different results.…”

“…Long term prognosis varies from normal renal function to early onset ESRD. 5 This is a retrospective and non-randomized study with the aim to establish whether measurement of serum creatinine at presentation would predict the longterm renal outcome in children with PUV? The main finding was that initial serum creatinine level alone was the most significant correlate of follow-up renal function (P = 0.001).…”

Posterior urethral valve

“…[44,45] Poor compliance is associated with the worst prognosis [46] but other factors implicated in the worsened prognosis in the boys include age at diagnosis, renal dysplasia, renal function before and after valve ablation, VUR, UTI, proteinuria, hypertension, and initial treatment. [42,43] The level of serum creatinine at 1 year old is shown to have a greater predictive value than the level at the time of diagnosis. [42] Because the levels of serum creatinine after relief of obstruction could refl ect more faithfully a kidney mass than those obtained before, and indeed, serum creatinine levels at 1 year old correlate strongly with the final outcome of patients.…”

“…A serum creatinine level of less than 8 mg/L at 1 year old is associated with normal renal function. [47,48] Recent studies [42,43] have shown that there is a clear prognostic relationship between the serum creatinine levels at 4-5 days after bladder catheterization and renal function.…”

“…[41] Researchers have noted different variables that may have predictive value or be responsible for long-term renal failure in patients with PUV. [42,43] Prenatal detection of posterior urethra obstruction at or before 24 weeks of gestation could predict a poor outcome [22] (Table). The bladder dysfunction that some of these patients have will be decisive in the development of their renal failure.…”