🧪 What is the Malarial Antigen Detection Test?

The Malarial Antigen Test is a rapid diagnostic test (RDT) or immunochromatographic assay used to detect Plasmodium antigens in the blood, typically from a finger-prick or venous sample.

It identifies specific proteins released by malaria parasites (Plasmodium spp.), such as:

• HRP-2 (Histidine-rich protein 2) – specific for Plasmodium falciparum
• pLDH (Plasmodium lactate dehydrogenase) – common to P. vivax, P. malariae, P. ovale
• Aldolase – pan-malarial marker

❓ Why is the Test Done?

To:

• Rapidly diagnose malaria, especially in febrile patients in endemic areas
• Distinguish Plasmodium species (e.g., P. falciparum vs P. vivax)
• Aid early treatment in suspected malarial fever
• Use in areas with limited access to microscopy or during outbreaks

📊 Interpretation of Results

A positive result confirms infection, but a negative result does not completely rule it out (especially in early infection or low parasitemia).

📈 Sensitivity & Specificity

• RDTs are highly specific but less sensitive than microscopy for detecting low-level infections.
• HRP-2 can persist in blood for weeks after parasite clearance, leading to false positives.

🧠 Associated Organs & Systems Affected by Malaria

🔄 Related / Follow-Up Tests

• Peripheral Blood Smear (PBS) – gold standard for species identification and parasitemia
• PCR for Plasmodium DNA – high sensitivity
• CBC – may show anemia, thrombocytopenia
• Liver and Renal Function Tests – to assess severity
• Rapid Dengue and Typhoid tests – in differential diagnosis of fever

✅ Fasting Required?

📝 Summary Table