A-107 A general description of the HTLV-1 Cohort at the Institute of Tropical Medicine Alexander von Humboldt (1989–2015)

Abstract

In Peru, the Institute of Tropical Medicine Alexander von Humboldt, in partnership with Hospital Cayetano Heredia, promotes specialized care for persons with HTLV-1 infection since 1989. Briefly, we offer pre and post-test counseling, diagnostic services, and medical attention. People are eligible for diagnostic services if they have: a prior seropositive result in Blood Banks; a first-degree relative or sexual partner with HTLV-1 infection; a potential diagnosis of HTLV-1-associated diseases (mainly: HTLV-1-associated myelopathy (HAM/TSP), Strongyloides stercoralis (SS) infection, T-cell leukemia/lymphoma, uveitis, infective dermatitis). Given the limited capacity to continuously afford confirmatory testing, HTLV infection is also diagnosed with repeatedly reactive ELISA tests. Cases receive post-test counseling, and specialized medical services. This setting has promoted our HTLV-1 Cohort; for those consenting, enrollment is at time of HTLV-1 testing. Until June 2015, 8845 persons were enrolled in the cohort; the median age was 38.8 years (interquartile range: 26.5–52.3), 5042 (57.5%) were women and 4337 (49.0%) did not report being related to someone with HTLV-1 infection and were thus defined as index cases. The leading reasons for HTLV testing were family studies (3987, 45.1%), followed by potential diagnosis of HTLV-1 associated diseases (3365, 38.0%), and seropositive results in Blood Banks (718, 8.5%). HTLV infection was diagnosed in 3359 persons (48.0%), including 1202 (13.6%) with available confirmatory testing. Most (58.3%) were women; the median age was 43 years (IQR: 31.0–55.6), but 285 were children. The proportion of HTLV diagnosis varied by reason for testing: 79.0% for those with potential HAM/TPS, 69.8% for potential ATL, 31.0% in cases with SS; 79.0% in donors and 34.0% when testing was done as part of family studies. At entry, the cases with HTLV infection included potential HAM/TSP (621, 18.5%); other complications mostly of infectious nature (338, 10.1%); SS infection (238, 7.0%), and ATL (5.6%). Most cases (1426, 43.0%) were lost to follow-up in the first year after diagnosis; in those remaining, with 8227 person-years of follow-up up to December 31, 2016, there were 88 incident cases of HAM/TSP, 47 of SS, and 8 of ATL. In those not lost-to-follow-up, 113 out of 1933 (5.6%) died. Our cohort offers a valuable platform to increase the quality of evidence regarding clinical consequences of HTLV-1 infection; at the same time, the number of pediatric cases remark the imperative need to implement sound actions for prevention of transmission of HTLV-1 from mother-to-child.