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Surveillance and diagnosis of Plasmodium falciparum malaria relies predominantly on rapid diagnostic tests (RDTs). However, false-negative RDT results are known to occur for a variety of reasons, including operator error, poor storage conditions, pfhrp2/3 gene deletions, poor performance of specific RDT brands and lots, and low-parasite-density infections. We used RDT and microscopy results from 85,000 children enrolled in Demographic Health Surveys and Malaria Indicator Surveys from 2009 to 2015 across 19 countries to explore the distribution of and risk factors for false-negative RDTs in Sub40 Saharan Africa, where malaria’s impact is greatest. We sought to (i) identify spatial and demographic patterns of false-negative RDT (FN-RDT) results, defined as a negative RDT but positive gold-standard microscopy test, and (ii) estimate the percentage of infections missed within community-based malaria surveys due to FN-RDT results. Across all studies, 19.9% [95% CI: 19.0 – 20.9] of microscopy-positive subjects were negative by RDT. The distribution of FN-RDT results was spatially heterogeneous. The variance in FN-RDT results was best explained by the prevalence of malaria, with an increase in FN46 RDT results observed at lower transmission intensities, among younger subjects, and in urban areas. The observed proportion of FN-RDT results was not predicted by differences in RDT brand or lot performance alone. These findings characterise how the probability of detection by RDTs varies in different transmission settings and emphasize the need for careful interpretation of prevalence estimates based on surveys employing RDTs alone. Further studies are needed to characterise the cost-effectiveness of improved malaria diagnostics (e.g. PCR or highly sensitive RDTs) in community52 based surveys, especially in regions of low transmission intensity or high urbanicity.

Five hundred girls with recurrent urinary tract infections and documented reflux were seen in our private practice during the last twenty years. All patients received medical treatment for three to forty-eight months (an average of fifteen months) after which the 250 who were not cured were submitted to corrective surgery. The primary reason for antireflux surgery is to protect the kidney from the damaging effect of a combination of high pressure and infection. Thus our criteria for operation included persistent infection, renal changes typical of past pyelonephritis, major reflux, and abdominal or flank pain. Our surgical cure rate after careful long-term follow-up is 96%. Our medical-surgical cure rate at the end of two years reached 88%. This experience has enabled us to evolve a rigorous point system providing common denominators regardind indications for operation. It emphasizes the desirability of attempting a medical cure for at least one year after urethral dilatation, except where major orifice defects and major reflux exist. This system should help to increase communication and coordination of efforts between pediatrician, radiologist, and urologist.