(1) Blood culture is the gold standard for the diagnosis of
bacterial infections. (2) Bone marrow culture is more sensitive than blood culture even in patients with
enteric fever receiving
antibiotics. (3) Microscopic agglutination test is considered the gold standard for diagnosing
leptospirosis; however, now
IgM ELISA and polymerase chain reaction (PCR) are more frequently used for diagnosis. (4)
Tuberculosis is diagnosed with the help of
nucleic acid amplification tests like Xpert MTB/RIF Ultra which also detects
rifampicin resistance. Other tests include microscopy, Lowenstein-Jensen and mycobacteria growth
indicator tube culture, line probe assay. (5) Tropical rickettsial
infections are diagnosed by serological reactions (Weil-Felix, ELISA for
antibodies) and PCR. (6) For
Brucellosis culture from blood, bone marrow or tissue specimens remain the mainstay in diagnosis. (7)
Dengue, Zika,
Crimean-Congo hemorrhagic fever, Ebola, hantavirus,
rabies are diagnosed with
reverse transcriptase-polymerase chain reaction. Serological tests like
IgM ELISA or paired sera samples for
IgG are also used for diagnosis.
HOW TO CITE THIS ARTICLE: Basu S, Shetty A. Laboratory Diagnosis of Tropical
Infections. Indian J Crit Care Med 2021;25(Suppl 2):S122-S126.