Hospital admissions in individuals with HTLV-1 infection in Spain

OBJETIVE: To examine the clinical burden and disease spectrum, as well as time trends for HTLV-1 and HTLV-2 hospital admissions. DESIGN: Retrospective, observational study using the Spanish National Hospital Discharge Database. METHODS: Information for the diagnostic codes HTLV, -1 and -2 using the International Classification of Diseases, Ninth Revision, Clinical Modification (ICD-9-CM) was retrieved from the national public registry since 1997 to 2015. RESULTS: From a total of 66,462,136 nationwide hospital admissions recorded during the study period, 135 included HTLV diagnosis, being HTLV-1 in 115 (85.2%) and HTLV-2 in 20 (14.8%). The overall hospital admission rate due to HTLV was 2.03 per million, without significant yearly changes. First admissions represented 104 (77%) whereas 31 (23%) were re-admissions. The median in-hospital stay for HTLV patients was 9 days. In-hospital death occurred in 11 (8.1%). The median age of individuals with HTLV admission was 48 years-old and 60 (44.4%) were female. HTLV was recorded as the main diagnosis in 20%. The most frequent clinical conditions recorded alongside HTLV diagnosis were myelopathy (61; 45.2%), leukemia/lymphoma (30; 22.2%), solid organ transplantation (14; 10.4%) and child delivery (7; 5.2%). CONCLUSION: The rate of HTLV diagnosis in hospitalized patients in Spain is low, roughly of 2 per million admissions. Despite continuous large immigrant flows from HTLV-1 endemic areas, no significant rising in hospitalizations due to HTLV-1 associated illnesses were noticed during the last two decades. Classical clinical complications of HTLV-1 infection, such as myelopathy and lymphoma account for more than two third of cases.