A Phase III Diagnostic Accuracy Study of a Rapid Diagnostic Test for Diagnosis of Second-Stage Human African Trypanosomiasis in the Democratic Republic of the Congo

Abstract

Objectives: To estimate the diagnostic accuracy of HAT Sero K-SeT for the field diagnosis of second-stage human African trypanosomiasis (HAT). Design: A phase III diagnostic accuracy design. Consecutive patients with symptoms clinically suggestive of HAT were prospectively enrolled. We compared results of the index test HAT Sero K-SeT with those of a composite reference standard: demonstration of trypanosomes in cerebrospinal fluid (CSF), or trypanosomes detected in any other body fluid AND white blood cell count in CSF >5/μl. Setting: Rural hospital in the Democratic Republic of the Congo. Participants: All patients above five years old presenting at Mosango hospital with a neurological problem of recent onset at the exclusion of trauma. Interventions: n.a. Main Outcome Measures: Sensitivity and specificity of HAT Sero K-SeT test. Results: The sensitivity of the HAT Sero K-SeT was 8/8 or 100.0% (95% confidence interval: 67.6 to 100.0%) and the specificity was 258/266 or 97.0% (94.2% to 98.5%). Conclusion: The high sensitivity of the HAT Sero K-SeT is in line with previously published estimates, though the sample of HAT cases in this study was small. The specificity estimate was very high and precise. This test, when negative, allows the clinician to rule out HAT in a clinical suspect in a hospital setting in this endemic region.

Keywords

• Diagnostic accuracy
• Sensitivity& specificity
• Rapid diagnostic test
• Human African trypanosomiasis
• Trypanosoma brucei gambiense