VARIABILITY OF LEISHMANIA-(LEISHMANIA)-INFANTUM AMONG STOCKS FROM IMMUNOCOMPROMISED, IMMUNOCOMPETENT PATIENTS AND DOGS IN SPAIN

Leishmania (Leishmania) infantum is the causative agent of both the cu taneous and visceral forms of leishmaniasis in southwest Europe; the d og is the main reservoir. In order to identify the L. (L.) infantum zy modemes present in Spain, a total number of 85 Leishmania stocks isola ted from dogs (31), HIV-positive patients (46) with visceral or cutane ous leishmaniasis, a patient with visceral leishmaniasis complicating renal transplantation (1) and immunocompetent patients (7) with viscer al or cutaneous leishmaniasis, have been characterized by isoenzyme ty ping. All canine stocks were MON-1, which is the most widespread zymod eme in the Mediterranean area. In immunocompetent patients three zymod emes were found: MON-1 (2), MON-24 (2) and MON-34 (3). Nine different zymodemes were obtained in stocks from HIV co-infected patients, indic ating a higher variability of L. (L.) infantum amongst them: MON-1 (in 21 stocks), MON-24 (7), MON-28 (1), MON-29 (3), MON-33 (7), MON-34 (1 ) and MON-183 (4). Two new zymodemes, MON-198 (1) and MON-199 (1), wer e described among HIV patients from Spain. The stock from the renal tr ansplanted patient was MON-1. The exclusive presence of certain zymode mes in immunocompromised patients and their absence in typical cases o f cutaneous and visceral leishmaniasis and in infected dogs suggests t wo possibilities: (i) an anthroponotic pattern of leishmaniasis where intravenous drug user-infected patients act as potential reservoir for these new zymodemes. In the latter, syringes could act as the vehicle s for infected monocytes; (ii) the cellular immune system could select virulent from non-virulent zymodemes in immunocompetent visceral leis hmaniasis patients.