Kala azar also known as Visceral Leishmaniasis Or Black fever. Kala-Azar caused by Leishmania Donovani is second largest parasitic killer in the world. Disease parasite migrate to the internal organs such as spleen, liver (hance it’s called Visceral Leishmaniasis) and bone Marrow.
Sir william Leishman first observed this protozoa in spleen at Dumdum, kolkata in 1900.
Kala azar is caused by bites from female phlebotomine sandflies, the vector of the Leishmania parasite.
The sand flies feed on humans and animals for blood, if blood containing Leishmania parasites, the next person to receive a bite will then become infected and develop leishmaniasis.
There are three forms of Leishmaniasis:
• Visceral Leishmaniasis – Kala-Azar
• Cutaneous Leishmaniasis
• Mucosal Leishmaniasis
STAGES:
• Amastigote form Or Leishmanial form or Aflagellar stage – It is found intracellular in macrophages, monocyte, neutrophil, reticulo endothelial cell
• Promastigote form or Leptomonad form or Flagellar stage – It is found in parasite sand fly ( phlebotomus argentipes)
TYPE
• Asymptomatic Kala-Azar
• Post Kala-Azar dermal Leishmaniasis
CAUSES
• Causative organism = Leishmania Donovani
• Definitive Host( In which a parasite reaches the sexual stage) = Human being, Sometime dogs
• Intermediate Host and Source of infection = Sand fly
• Infective form = Promastigote form
• This disease affects of the poorest people due to malnutrition, population displacement, poor housing, weak immune system
SYMPTOMS
FOR VISCERAL LEISHMANIASIS
• Incubation period for 3- 6 months
• Fever
• Continuous or remittent type of fever
• Splenic Enlargement
• liver enlarged but not so much as spleen
FOR POST KALA-AZAR – dermal lesions are three types
• Depigmented Macules – Earliest lesion on trunk and extremities
• Erythrematous patches – Appears on nose, cheek, chin, having butterfly distribution called Butterfly Erythema. Very photosensitive prominent towards the noon
• Yellow pink nodules appear on face. Nodules are soft pain less
GENERAL FEATURES
• Malaise
• Emaciation
• Anaemia
• Loss of appetite
• Pallor
• Weightloss
• Skin and entire body dry and rough
RISK FACTORS
• Socioeconomic condition
• Malnutrition
• Environmental changes
• Population Mobility
• Climate changes
INVESTIGATION
A. DIRECT :
• Peripheral Blood =
Thick smear
Amastigote form ( Leishman Stain)
• Blood culture in N. N. N (Novy-MacNeal-Nicolle) Medium = Promastigote form
• Biopsy Material (Collection of tissue from alive person and study) =
– Lymph Node Puncture ( Amastigote form)
– Bone marrow study / Sternal/ iliac crest puncture ( Amastigote form)
– Spleen Puncture ( Amastigote form)
B. INDIRECT:
• Serum Test
– Aldehyde Test >Positive after 3month > Due to increase in Gamma Globulin
– Antimony Test > Less reliable than aldehyde test
– Complete Fixation Test With WKK (Witebsky, Klingenstein, Kuhn) Antigen
• Blood Count
– TLC ( Total Lymphocytic Count)=Leukopenia
– DLC (Diffenential Leukocyte Count) = Monocytosis, Lymphocytosis
– Anaemia
• Treatment depend on condition and severity
• If untreated death occures due to complications with
Amoebic Dysentery
Pneumonia
Pulmonary Tuberculosis
Septic infection
• Antiparasitic Medicine
• Antifungal medication
PREVENTION AND CONTROL
• Early diagnosis and effective prompt treatment
• Vector control or Sand fly control – Use of insecticide spray to treated nets, decrease the number pf sand fly, personal protection, environmental management
• Effective disease surveillance
• Control of animal reservoir host
