title: Resistance to treatment in Kala-azar: speciation of isolates from northeast India.
abstract: Kala-azar in India is becoming increasingly difficult to treat, which may be due to the presence of species other than Leishmania donovani; Leishmania tropica was reported to cause the same clinical syndrome in the area. Over the past 3 years, we have collected samples from 241 patients with visceral leishmaniasis from across the region. Of the 189 isolates that grew on diphasic medium, 159 were successfully transferred to liquid medium for typing. Clinically, 80% of these were resistant to antimony. Lipophosphoglycan-specific monoclonal antibodies were used to distinguish the 2 species by agglutination of promastigotes; all 159 were shown to be L. donovani. Eighty-three isolates were confirmed to be L. donovani by isoenzyme analysis, by amplification of kinetoplast DNA, or both, in comparison with multiple reference strains; none were L. tropica. Thus, the rising incidence of clinical resistance to treatment is unlikely to be due to a different species causing kala-azar in north Bihar.
authors.affiliation: Kala-azar Medical Research Center, Department of Medicine, Institute of Medical Sciences, Banaras Hindu University, Varanasi, India.
authors.forename: S
authors.initials: S
authors.lastname: Sundar
authors.forename: K
authors.initials: K
authors.lastname: Pai
authors.forename: R
authors.initials: R
authors.lastname: Kumar
authors.forename: K
authors.initials: K
authors.lastname: Pathak-Tripathi
authors.forename: A A
authors.initials: AA
authors.lastname: Gam
authors.forename: M
authors.initials: M
authors.lastname: Ray
authors.forename: R T
authors.initials: RT
authors.lastname: Kenney
mesh_terms: D000293:Adolescent; D000328:Adult; D000818:Animals; D000913:Antibodies, Protozoan / Q000097:blood; D000967:Antimony Sodium Gluconate / Q000008:administration & dosage / Q000627:therapeutic use*; D000981:Antiprotozoal Agents / Q000008:administration & dosage / Q000627:therapeutic use*; D002648:Child; D018105:DNA, Kinetoplast / Q000737:chemistry / Q000302:isolation & purification; D016054:DNA, Protozoan / Q000737:chemistry / Q000302:isolation & purification; D004351:Drug Resistance; D004588:Electrophoresis, Cellulose Acetate; D005260:Female; D006801:Humans; D007194:India / Q000453:epidemiology; D007893:Leishmania donovani / Q000145:classification* / Q000235:genetics; D007895:Leishmania tropica / Q000145:classification* / Q000235:genetics; D007898:Leishmaniasis, Visceral / Q000188:drug therapy* / Q000469:parasitology*; D008297:Male; D008875:Middle Aged; D018512:Parasitemia / Q000188:drug therapy / Q000469:parasitology
chemical_list: D000913:Antibodies, Protozoan; D000981:Antiprotozoal Agents; D018105:DNA, Kinetoplast; D016054:DNA, Protozoan; D000967:Antimony Sodium Gluconate