Importance of Clinical Suspicion in Rapid Diagnostic Test Negativity in Malaria: Two Case Reports

Abstract

Introduction: Malaria is a life-threatening disease caused by infection with Plasmodium parasites. Rapid diagnostic tests (RDTs) have been used for the diagnosis of malaria without special equipment by unskilled personnel over the last 15 years. The treatment should only be given after the clinical diagnosis confirmed by RDT or microscopy. RDTs' specificity and sensitivity have been reported as >95% by the World Health Organization - Foundation for Initiative New Diagnostics (WHO-FIND). Case Report: A 30-years-old male and a 23-years-old female presented to our emergency department with fever and history of a visit to a malaria-endemic country. Plasmodium trophozoites were seen in the blood smear samples via light microscopy. However, RDTs were negative. The patients were treated according to their pathogens. Conclusion: Rarely, RDT might result in a false negative in the diagnosis of malaria. People travelling to endemic areas should be closely monitored. Emergency department physicians should not neglect microscopy which is the gold standard for diagnosis of malaria.

Keywords

• Clinical Microbiology
• Emergency Departments
• Infectious Diseases
• Parasitology
• Plasmodium

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