2. What is Kala-Azar
• Kala-azar means dark pigmentation which is
characteristic of cases of visceral
leishmaniasis. It is caused by Leishmania
donovani bodies and may be present either in
endemic, epidemic or sporadic forms. It is
widely prevalent in India in epidemic form in
states of Bihar, Assam and Bengal. Kala azar
found in East and North Africa is a disease of
young children and young adults, being more
common in males as compared to females.
5. KALA AZAR
• Leishmaniasis is a disease caused by protozoan
parasites of to the genus Leishmania and is
transmitted by the bite of sand fly.
• Human infection is caused by about 21 of 30
species that infect mammals. These include the L.
donovani complex with three species (L. donovani,
L. infantum, and L. chagasi
• Infections range from asymptomatic to progressive,
fully developed kala-azar.
• Incubation period is usually 2 – 4 months.
• Symptoms – Begins with low-grade fever and
malaise, followed by progressive wasting, anemia,
and protrusion of the abdomen from enlarged liver
• Fatal after 2 – 3 years if not treated.
• In acute cases with chills, fevers up to 104⁰ F and
vomiting; death may occur within 6 – 12 months.
• Immediate cause of death is usually an invasion of a
secondary pathogen that the body is unable to
7. Leishmaniasis is Neglected Disease
• Leishmaniasis is a globally important but
neglected disease, affecting
approximately two million people every
year. For most people, infection results in
a slow-to-heal skin ulcer. In others,
however, the parasite targets the liver,
spleen and bone marrow, leading to over
70,000 deaths annually.
8. The Parasite
15. • Amastigotes (*)
donovani in the
cells of a
μm in diameter.
16. Morphology and Life Cycle
micrometers, with a
large nucleus and
• Amastigotes mainly
live within cells of
the RE system, but
have been found in
nearly every tissue
and fluid of the
17. Life cycle
• The organism is transmitted by the
bite of several species of blood-feeding
sand flies (Phlebotomus)
which carries the promastigote in
the anterior gut and pharynx. It
gains access to mononuclear
phagocytes where it transform into
amastigote and divides until the
infected cell ruptures.
19. Life cycle
• The released organisms infect other
cells. The sand-fly acquires the
organisms during the blood meal,
the Amastigote transform into
flagellate Promastigote and multiply
in the gut until the anterior gut and
pharynx are packed. Dogs and
rodents are common reservoirs. 19
23. • Pallor in hands of a
24. Laboratory diagnosis
• Blood counts: Anaemia, neutropenia, thrombocytopenia
• A/G ratio reversed (n-4.5:2, in kala-azar-2.8:4)
• Parasitological Diagnosis
• Needle biopsy/aspiration
• Animal inoculation
• Immunological tests
• Non-specific tests
• Aldehyde tests
• Antimony test
• A:G Complement fixation test with W.K.K antigen
25. • Immunological tests
• Non-specific test
• Aldehyde test
• Antimony test
• Complement fixation test with W.K.K antigen
• Specific tests
• Direct agglutination test(DAT)
• Indirect haemagglutination test (IHA)
• Indirect fluorescent antibody test(IFAT)
26. Parasitological diagnosis:
Bone marrow aspirate
Lymph node aspiration
Microscopy – PBF, Buffy coat smear
Animal inoculation- golden hamester
28. L. donovani bodies
L. donovani bodies may be
demonstrated in buffy
coat preparations of
blood and bone
PBF is made with straight
Aspirates taken from
enlarged lymph nodes
show parasites in 60
percent of cases.
29. Culturing of the Parasite
• Organisms can be
cultured in Nicolle-
media) media from
splenic or bone
• NNN medium-Biphasic media- 2 parts of salt
agar+1 part of defibrinated rabbit blood,
melted & cooled to 48⁰C ice, inoculated into
water of condensation, incubated at 22-25⁰C
for the 21 days.
• Hockmeyer medium- Insect cell culture
medium+ foetal calf serum+ penicillin+
streptomycin( detected after 2-3 d)
• Schneider Dorsophila Medium
31. Promastigote in culture in NNN
medium (magnification 100×)
NNN culture medium
Promastigotes growing in culture medium Bone marrow aspirate -“rosette” of
extra-cellular Promastigotes (Giemsa stain31).
32. Immunological Diagnosis:
• Specific serologic tests:
• Direct Agglutination Test (DAT),
• CFT for detection of antibodies
• Rapid immunochromatic test(ICT): By using
• Molecular Methods: PCR & RT-PCR.
33. Direct agglutination test
• Direct agglutination test
(DAT) based on
agglutination of the
promastigotes is useful
in endemic regions. Its
sensitivity ranges from
91-100% and specificity
from 72 to 100%.
• ELISA is an important
sero diagnostic tool
for leishmaniasis. It
is a highly sensitive
test and its
upon the antigen
35. Chromatographic strip test
• A ready to use immuno
test based on rk 39
antigen has been
developed as a rapid test
for diagnosis of kala azar.
An important limitation of
this test is the presence
of antibodies in healthy
controls hailing from
36. • Non specific serological tests for
• Napier’s Aldehyde test: Patient’s sera is mixed
with a drop of 40% formalin in a test tube.
Positive test is indicated by jellification.
• Chopra’s antimony test: Positive test is by
formation of profuse flocculation when
patient ‘ sera is mixed with 4% urea stilbamine
Skin test ( leishmanin test or Montenegro
test) It is a delayed hypersensitivity skin test
for survey of populations and follow-up after
treatment - 0.2 ml(6-10 million/ml of killed
promastigotes in 0.5% phenol saline)
injected—erythema ≥ 5mm→ +ve after 6-8
weeks of cure.
38. The leishmanin skin test (LST) or MST (Montenegro skin test)
A positive leishmanin skin test
•Reference standards -antigens & performance (reading)- not developed.
•Most antigens, crude extracts of parasites, neither sensitive nor specific.
•Positivity not demonstrable until 5 months after the acute phase of VL-20%
• May or may not be positive for PKDL.
•Persistence of the lesions has been frequently associated with non reactivity in the
LST and high levels of anti-leishmanial antibodies.
• Pentavalent antimony (Pentostam)
• Amphotericin B
Treatment of complications:
• Infections etc.
• Vector control
• Reservoir control
• Treatment of active cases
41. Management of Kala-azar Patients
• It includes both supportive and curative. All
patients of Kala azar should preferably be
hospitalized. Any infection complicating the
disease be treated by use of proper
antibiotics. Nutrition must be maintained.
Cases with severe anemia may require blood
transfusions. Pentavalent antimony
compounds are the drug of choice. Sodium
antimony gluconate (Pentostam) is the most
commonly used drug.
42. Kala-azar prevention:
• Multipronged approach is needed.
• Sand-flies are extremely sensitive to
insecticides & vector control through
insecticide spray is very important.
• Mosquito nets or curtains treated
with insecticides will keep out the
43. Kala-azar prevention:
• In endemic areas with zoonotic transmission,
infected or stray dogs should be destroyed.
• In areas with anthroponotic transmission,
early diagnosis & treatment of human
infections, to reduce the reservoir & control
epidemics of VL, is extremely important.
• Serology is useful for screening of suspected
cases in the field.
• No vaccine is currently available .
46. Post Kala Azar Dermal
Normally develops <2 years after recovery
Restricted to skin
Rare but varies geographically(10% of cases
in India and 3% of cases in Africa)
•Non ulcerative skin lesin.
•Late sequale of VL.
•1-2 years after recovery fron VL.
•Currently, PKDL is reported to occur in only 1% of Indian VL
Nodular skin lesions in PKDL
•3 major representations-
(i) Erythematous indurated lesions on the butterfly area of
(ii) Multiple symmetrical hypopigmented macules with
irregular margins that may coalesce, having generalized
distribution to the extremities and trunk; and
(iii) Combination of papules, nodules and plaques.
48. Fig. Clinical presentation in PKDL (A) PKDL nodular and popular lesions on face and
hypopigmented macules on neck in a patient
with polymorphic presentation (B) hypopigmented macules on trunk in a patient with macular
PKDL. (C) Erythematous and indurated
lesions over the butterfly area of face. 48
49. Complications of PKDL
1. Blindness due to corneal involvement.
2. Recently, nerve involvement in Indian PKDL reportd.
• Nowadays – reported from South America, Europe & India.
• Recurrence of VL following PKDL reported.
• LD bodies rich nodular skin lesions -sole reservoir to disseminate in
absence of zoonotic transmission.
50. Grey areas in PKDL
1. The factors of parasite/host origin -drive the parasite to shift from viscera to dermis. --It is
not known it is the residual parasite after VL infection, attributed to altered immune status or
is introduced upon re-infection by sandfly vector.
Antimony therapy for PKDL patients needs to be continued for much longer duration than
for VL patients (4 months instead of 4 wk for VL).
• Recently-High interleukin-10 (IL-10) levels in skin & peripheral blood.
-High level of C reactive protein in plasma of patients with VL
Predictive of the subsequent development of PKDL.