Blood borne parasite :
The blood borne parasites which can be found in the bloodstream of an infected person are called blood borne parasites.
Name some blood borne parasite :
- Leishmania donovani causes Kala-azar
- Plasmodium species causes Malaria
- Wuchereria bancrofti causes Filariasis
Laboratory diagnosis of kala-azar:
Principle:
Leishmaniasis can be diagnosed by demonstration of the parasite (LD bodies) from the cutaneous, mucosal lesions and incase of visceral leishmaniasis from Bone marrow, Spleen or Lymph node aspirate. It can also be diagnosed by detection of antigen or antibody by immunological tests and isolation of the organism by culture if facilities are available. Nucleic acid techniques are also helpful.
Specimen collection:
Aspiration of bone marrow, spleen, lymph nodes, buffy coat of blood.
Microscopic examinations:
- Leishman (or Giemsa) stained smear.
- Findings: Amastigote form (LD bodies) in bone marrow, splenic aspirate and within blood monocytes.
Isolation and identification from culture:
- NNN media (Novy, Mac Neal, Nicole).
- Incubation- at 22° C.
- Incubation time-1 to 2 weeks.
- Findings- promastigote forms of parasites are found.
Serological tests:
Specific:
For detection of antibody–
- ICT (ImmunoChromatographic Test)
- DAT (Direct Agglutination Test)
- IFAT (Indirect Fluorescent Antibody Test)
- CFT (Complement Fixation Test)
For detection of antigen-
- ELISA (Enzyme Linked ImmunoSorbent Assay)
- RIA (Radio Immuno Assay)
Non-specific:
- Aldehyde test for detection of high globulin.
- Antimony test.
- Blood count-Decrease WBC. RBC, Platelet.
NA based techniques:
PCR (Polymerase chain reaction).