A Cross-Sectional View of HTLV-1: From Childhood to Adulthood in an Endemic Region of Colombia

Human T-cell lymphotropic virus type 1 (HTLV-1) affects between 10 and 20 million people worldwide and remains a neglected infection in endemic areas such as southwestern Colombia. This study aimed to describe the clinical and demographic characteristics of forty-four patients with confirmed HTLV-1 infection treated at a referral center between January 2021 and December 2023. A retrospective case series analysis was conducted, including twenty-three pediatric patients, sixteen adults, and five pregnant women, with confirmation by Western Blot. Among the pediatric population, 52.2% presented with anemia, leukocytosis, and pulmonary coinfections, mainly due to Aspergillus spp. and Mycobacterium tuberculosis; 47.8% had infective dermatitis, and 45.5% had malnutrition. In adults, adult T-cell leukemia/lymphoma (ATLL) was the main manifestation (56.3%), followed by neurological involvement (43.7%). The mortality rate among adults was 68.7%, and one death was recorded in the pediatric group. The pregnant women had a mean age of 33 years and an average gestational age of 31.6 weeks at diagnosis; all were asymptomatic carriers. These findings highlight the clinical burden of HTLV-1 across different age groups and reinforce the need to implement public health strategies, including prenatal screening and comprehensive clinical follow-up in endemic areas.