Iso-enzymatic variability of Leishmania infantum in Spain

Area of Science:

• Medical Parasitology
• Infectious Diseases
• Immunology

Background:

• Leishmaniasis is increasingly prevalent in HIV-positive individuals across the Mediterranean basin.
• Spain reports the highest number of Leishmania/HIV co-infection cases in Southern Europe.
• Leishmania infantum is the primary species implicated in these co-infections.

Purpose of the Study:

• To characterize Leishmania infantum isolates from Spain, focusing on those co-infected with HIV.
• To investigate the genetic variability and zymodeme diversity of Leishmania infantum in HIV-positive patients.
• To understand the clinical implications of Leishmania infantum variants in immunocompromised individuals.

Main Methods:

• Iso-enzymatic analysis of 359 Spanish Leishmania infantum isolates collected since 1984.
• Characterization of isolates primarily from HIV-positive patients (94.6%).
• Comparison of zymodeme profiles between isolates from immunocompetent and HIV-positive individuals.

Main Results:

• Significant iso-enzymatic variability was observed among Leishmania infantum isolates.
• HIV-positive patients harbored variants typically considered dermotropic in immunocompetent hosts.
• New zymodemes of Leishmania infantum emerged within the HIV-positive population.

Conclusions:

• Leishmania infantum exhibits considerable genetic diversity in HIV-positive individuals in Spain.
• HIV co-infection can alter the tropism of Leishmania infantum variants, leading to visceralization.
• The emergence of novel zymodemes highlights the impact of HIV on Leishmania epidemiology and pathogenesis.