Wrong sample dispensing may cause false positive malaria test

Area of Science:

• Medical Diagnostics
• Parasitology
• Blood Transfusion Safety

Background:

• Malaria parasite (MP) rapid diagnostic tests (RDTs) are crucial for malaria detection but are susceptible to false positive (FP) and false negative results.
• Interference from substances within blood samples can lead to inaccurate RDT results.

Purpose of the Study:

• To report the first-time detection of a false positive result in a malaria parasite RDT.
• To identify the cause of the false positive result as an incorrect sample dispensing technique.

Main Methods:

• A 36-year-old female whole blood donor's sample was tested using an MP RDT.
• The initial test yielded a reactive (false positive) result due to the technician collecting red blood cells instead of the recommended whole blood.
• The sample was re-tested after proper mixing, and peripheral blood smear examinations were performed.

Main Results:

• The initial MP RDT showed a false positive result.
• Subsequent testing of the properly mixed sample yielded a non-reactive result.
• Peripheral blood smear examinations for malaria parasites were negative.

Conclusions:

• Incorrect sample dispensing, specifically collecting red blood cells instead of whole blood, can lead to false positive results in malaria parasite RDTs.
• Proper training on sample collection techniques is essential for accurate malaria diagnosis using RDTs.
• This case highlights a critical procedural error that can compromise blood transfusion safety and diagnostic accuracy.