The Validity of Haematuria and Proteinuria by chemical reagent strip for diagnosis of Schistosoma haematobium infection

Document Type : Original Article

Author

Society of Pathological Biochemistry and Hematology, Egypt

Abstract

Background: Urinary schistosomiasis is a chronic water-borne disease that affects the lives of millions of people globally especially the rural areas of developing countries, Microscopic examination can quantify the intensity of the S.haematobium infection, however, it is relatively insensitive especially in situations involving low-level infections. Hematuria and proteinuria have been considered as alternatives for microscopic testing of urine to diagnose S.haematobium infection, and as a single tool in large-scale control programs. Subjects and methods: This study is a cross-sectional study designed to evaluate haematuria and proteinuria by chemical reagent strip to determine urinary schistosomiasis in the study population, to overall sample was 1000 patients of different ages also, urine microscopic examination was done for detection of S.haematobium eggs by sedimentation centrifugation and nuclepore filtration techniques. Results:  The results showed that haematuria by chemical reagent strips had a sensitivity of 27.8% and specificity of 63.4%. When proteinuria was considered, sensitivity increased to 67.1% also specificity increased to 80.7%. When both haematuria and proteinuria were considered, sensitivity was 45.2% and specificity 85.9%. sensitivity in between the previous results. PPVs ranged between 6.13% and 22.9% whereas NPVs ranged between 91.1% and 96.6%. As for diagnostic efficiency, it was best for both haematuria and proteinuria (83.1%) followed by proteinuria 79.6% and least for haematuria (60.7%), where the area under the curve (AUC) was sufficient for both haematuria and proteinuria 0.61 and good for proteinuria (0.71), where it was not useful for haematuria (0.48). Conclusion and Recommendations: Most previous studies showed blood in urine or microhaematuria is more important than protein and used chemical reagent strips to detect microhaematuria and not protein. While this study showed detect of protein by chemical reagent strip is more important than microhaematuria by chemical reagent strip, and statistical parameters tested were higher with proteinuria than haematuria. The sensitivity, specificity, positive and negative predictive value, the likelihood ratio for positive results, diagnostic efficiency, and area under the curve all were higher in proteinuria than haematuria. The sum of proteinuria and haematuria had more specificity. In this study, we demonstrate that the use of urine reagent strips for both proteinuria and haematuria might be considered for the diagnosis of S. haematobium where microscopy is unavailable.

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