DIAGNOSIS OF MALARIA BY REAL-TIME POLYMERASE CHAIN REACTION IN CASES OF NEGATIVE MALARIAL PARASITE ON MICROSCOPY

Abstract

Objective: To determine the frequency of malaria by polymerase chain reaction in malarial parasite negative samples on microscopy.

Study Design: Cross-sectional study.

Place and Duration of Study: Haematology department of Pakistan Naval Ship, Shifa Hospital, from Jan 2018 to Oct 2018.

Methodology: This study involved 150 adults of both genders with suspicion of malaria but negative malarial parasite on microscopy. Polymerase chain reaction was performed on blood samples from selected patients as per protocol. Outcome variable was the frequency of polymerase chain reaction positivity for malarial parasite. A pre-designed proforma was used to collect the data that was analyzed through SPSS version 20.0.

Results: The mean age of patients was 29.51 ± 8.73 years. The majority (75.3%) of the patients had undiagnosed fever. Only a small proportion of patients had hemolytic anemia (4.0%), splenomegaly (4.0%), acute renal failure (1.3%) and jaundice (1.3%). Polymerase chain reaction was positive in 3 (2.0%) cases. There was no significant difference in the frequency of positive polymerase chain reaction across underlying signs/symptoms except splenomegaly. Patients with splenomegaly had a significantly higher frequency of positive polymerase chain reaction (16.7% vs. 1.4%; p=0.009).

Conclusion: The frequency of positive polymerase chain reaction was found to be 2.0% in malarial parasite negative samples on microscopy. It was significantly higher among patients with splenomegaly.