A UK single-centre retrospective analysis of malaria diagnostics

Abstract

Objectives: The objective of the study was to assess adherence to current UK (2016) guidelines on the investigation of patients with suspected malaria, and if practice of analysing serial blood films is necessary to exclude a diagnosis of malaria in febrile returning traveller. Methods: All samples taken in 7-year period sent for the examination of malaria parasites to a tertiary referral tropical medicine centre were included in the analysis. Samples were separated into a total of 2082 patient episodes (all samples sent within 30 days of initial sample). Data were additionally collected on parasite subspecies and travel history. Results: Adherence to current malaria diagnostic guidelines is poor, especially for patients assessed in primary care. All positive diagnoses of malaria were made on initial blood film sent for analysis; negative predictive value of blood film with no malaria parasites was identified 100% in excluding diagnosis of malaria. Conclusions: Serial blood films may not be necessary to exclude diagnosis of malaria in specialist centres. Risk stratification of febrile patients returning from endemic world regions may help in selecting patients requiring further blood film analysis after initial negative film.

Keywords

• Malaria
• Diagnosis
• Blood tests
• Microscopy
• Antigen