Kala-azar
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Diseases Page
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- Kala-azar is a slow progressing indigenous disease caused by a
protozoan parasite of genus Leishmania
- In India Leishmania donovani is the only parasite
causing this disease
- The parasite primarily infects reticuloendothelial system and may
be found in abundance in bone marrow, spleen and liver.
- Post Kala-azar Dermal Leishmaniasis (PKDL) is a condition when
Leishmania donovani invades skin cells, resides and develops
there and manifests as dermal leisions. Some of the kala-azar cases
manifests PKDL after a few years of treatment. Recently it is believed
that PKDL may appear without passing through visceral stage. However,
adequate data is yet to be generated on course of PKDL
manifestation
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What are Signs & Symptoms of Kala-Azar?
- Recurrent fever intermittent or remittent with often double
rise
- loss of appetite, pallor and weight loss with progressive
emaciation
- Splenomegaly – spleen enlarges rapidly to massive enlargement,
usually soft and nontender(not painful)
- Liver – enlargement not to the extent of spleen, soft, smooth
surface, sharp edge
- Lymphadenopathy – not very common in India
- Skin – dry, thin and scaly and hair may be lost. Light coloured
persons show grayish discolouration of the skin of hands, feet, abdomen
and face which gives the Indian name Kala-azar meaning “Black
fever”
- Anaemia – develops rapidly
- weakness
Anaemia with emaciation and gross splenomegaly produces a typical
appearance of the patients |
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| Post Kala-azar Dermal Leishmaniasis is a condition in which
Leishmania donovani parasites are found in skin. PKDL develops in some
of the Indian kala-azar patients usually 1-2 years or more following
recovery of Kala-azar; less commonly without suffering from
Kala-azar |
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What are Signs & Symptoms of PKDL?
Types of morphological lesions:
- Early hypopigmented macules similar to macular lesions of
Lepromatous Leprosy but normally less than 1 cm. Usually occur on face
but can affect any part of the body.
- Later (after a variable period of months or years) diffuse nodular
lesions on those macules
- Erythematous butterfly rash which may be aggravated by exposure to
Sunlight; an early sign of PKDL
- Erythematous papules and nodules which usually occur on face,
especially the chin.
- Lesions progressive over many years , seldom heal
spontaneously
Rare manifestations of PKDL include:
- Multiple lesions coalesce to form larger plaque type lesions
- Verrucous lesions (hands and feet)
- Papillomatous lesions (on muzzle area of face, nose, chin, and
lips)
- Hypertrophic lesions (eyelids, nose and lips)
- Xanthematous rash (orange plaque on axillary fold, cubital fossae,
inner thighs, outer canthus of the eye and perioral)
- Pityriasis rosea like lesions
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- Visceral leishmaniasis (VL) has emerged as an opportunistic
infection in HIV and other immunosuppressed patients
- More than 1000 cases of HIV and VL are reported from 25 countries.
However, in India yet not a serious problem
- VL may be first Opportunistic Infection in asymptomatic HIV-I
infected person
- Also occurs in advanced stage of AIDS
- All co-infected patients are not symptomatic
- Diagnosis may be altered because symptoms may be of short duration;
fever and spleen may not be marked; Leishmania antibodies may
be undetectable.
- However peripheral blood smears of buffycoat and blood culture may
yield good results
- Response to treatment is poor; drug side effects may be more and
relapses may be common
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- Kala-azar is a vector borne disease
- Sandfly of genus Phlebotomus argentipes are the only known
vectors of kala-azar in India
- Indian Kala-azar has a unique epidemiological feature of being
Anthroponotic; human is the only known reservoir of
infection
- Female sandflies pick up parasite (Amastigote or LD bodies)while
feeding on an infected human host.
- Parasite undergo morphological change to become flagellate
(Promastigote or Leptomonad), development and multiplication in the gut
of sandflies and move to mouthparts
- Healthy human hosts get infection when an infective sandfly vector
bites them
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- There is only one sandfly vector of Kala-azar in India
Phlebotomus aregentipes
- Sandflies are small insects, about one fourth of a mosquito.
The length of a snadfly body ranges from 1.5 to 3.5 mm.
- Adult is a small fuzzy, delicately proportionate fly with erect
large wings. The entire body including wings is heavily clothed with
long hairs.
- Life cycle consists of egg, four instages of larvae, pupa and
adult. The whole cycle takes more than a month, however, duration
depends on temperature and other ecological conditions
- They prefer high relative humidity, warm temperature, high subsoil
water and abundance of vegetation.
- Sandflies breed in favourable micro-climatic conditions in places
with high organic matter that serve as food for larvae
- These are ecologically sensitive insects, fragile and cannot
withstand desiccation
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Clinical:
A case of fever of more than 2 weeks
duration not responding to antimalarials and antibiotics. Clinical
laboratory findings may include anaemia, progressive leucopenia
thrombocytopenia and hypergammaglobulinemia
Laboratory:
- Serology tests: Variety of tests are available for
diagnosis of Kala-azar. The most commonly used tests based on relative
sensitivity; specificity and operationally feasibility include Direct
Agglutination Test (DAT), rk39 dipstick and ELISA. However all these
tests detect IgG antibodies that are relatively long lasting. Aldehyde
Test is commonly used but it is a non-specific test. IgM detecting
tests are under development and not available for field use.
- Parasite demonstration in bone
marrow/spleen/lymphnode aspiration or in culture medium is the
confirmatory diagnosis. However, sensitivity varies with the organ
selected for aspiration. Though spleen aspiration has the highest
sensitivity and specificity (considered gold standard) but a skilled
professional with appropriate precaustions can perform it only at a
good hospital facility.
Differential Diagnosis:
- Typhoid
- Miliary tuberculosis
- Malaria
- Brucellosis
- Amoebic liver abscess
- Infectious mononucleosis
- Lymphoma, Leukemia
- Tropical splenomegaly
- Portal hypertension
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- Kala-azar Drugs available in India
- Sodium Stibogluconate (indigenous manufacture, registered for use
& sale)
- Pentamidine Isethionate: (imported, registered for use)
- Amphotericin B: (indigenous manufacture, registered for use and
sale)
- Liposomal Amphotericin B: (indigenous manufacture & import,
registered for use and sale)
- Miltefosine (imported/ registered for use & sale)
First Line Drugs
A. Short Term
- Areas with SSG sensitivity >90%
SSG IM/IV 20mg/kg/day X 30 days
- Areas with SSG sensitivity <90%
Amphotericin B 1mg/kg b.w. IV infusion daily or alternate day for
15-20 infusions. Dose can be increased in patients with incomplete
response with 30 injections
B. Long Term
- Areas with high level of SSG resistance
(>20%)
- Miltefosine 100 mg daily x 4 weeks (after phase III
studies completed with proven safety & efficacy)
- Areas with SSG sensitivity >80%
- SSG IM/IV 20mg/kg/day X 30 days
- Miltefosine 100 mg daily x 4 weeks (after phase III
studies completed with proven safety & efficacy)
A. SSG Failures
Amphotericin B 1mg/kg b.w. IV infusion daily or alternate day for
15-20 infusions. Dose can be increased in patients with incomplete
response with 30 injections
B. SSG and Miltefosine Failures
Liposomal Amphotericin B (when final results are available with proven
efficacy and safety)
Treatment of PKDL
- SSG in usual dosages for KA could be given up to 120
days
- Repeated 3-4 courses of Amphotericin B can be given in patients
failing SSG treatment
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- Endemic in eastern States of India namely Bihar, Jharkhand, Uttar
Pradesh and West Bengal
- 48 districts endemic; sporadic cases reported from a few other
districts
- Estimated 165.4 million population at risk in 4 states
- Mostly poor socio-economic groups of population primarily living in
rural areas are affected
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- An organized centrally sponsored Control Programme launched in
endemic areas in 1990-91
- Government of India provided kala-azar medicines, insecticides and
technical support and the State governments implemented the programme
through primary health care system and district/zonal and State malaria
control organizations and provided other costs involved in strategy
implementation
- Programme strategy included:
Vector control through IRS with DDT up to 6 feet height from the
ground twice annually
Early Diagnosis and Complete treatment
Information Education Communication
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