Clinical Associations of Human T-Lymphotropic Virus Type 1 Infection in an Indigenous Australian Population

Introduction:in resource-poor areas,infectious diseases may be important causes of morbidity among individuals infected with the human t-lymphotropic virus type 1 (htlv-1). we report the clinical associations of htlv-1 infection among socially disadvantaged indigenous adults in central australia.methodology and principal findings:htlv-1 serological results for indigenous adults admitted 1st january 2000 to 31st december 2010 were obtained from the alice springs hospital pathology database. infections,comorbid conditions and htlv-1 related diseases were identified using icd-10 am discharge morbidity codes. relevant pathology and imaging results were reviewed. disease associations,admission rates and risk factors for death were compared according to htlv-1 serostatus. htlv-1 western blots were positive for 531 (33.3%) of 1595 indigenous adults tested. clinical associations of htlv-1 infection included bronchiectasis (adjusted risk ratio,1.35; 95% ci,1.14-1.60),blood stream infections (bsi) with enteric organisms (arr,1.36; 95% ci,1.05-1.77) and admission with strongyloidiasis (arr 1.38; 95% ci,1.16-1.64). after adjusting for covariates,htlv-1 infection remained associated with increased numbers of bsi episodes (adjusted negative binomial regression,coefficient,0.21; 95% ci,0.02-0.41) and increased admission numbers with strongyloidiasis (coefficient,0.563; 95% ci,0.17-0.95) and respiratory conditions including asthma (coefficient,0.99; 95% ci,0.27-1.7),lower respiratory tract infections (coefficient,0.19; 95% ci,0.04-0.34) and bronchiectasis (coefficient,0.60; 95% ci,0.02-1.18). two patients were admitted with adult t-cell leukemia/lymphoma,four with probable htlv-1 associated myelopathy and another with infective dermatitis. independent predictors of mortality included bsi with enteric organisms (arr 1.78; 95% ci,1.15-2.74) and bronchiectasis (arr 2.07; 95% ci,1.45-2.98).conclusion:htlv-1 infection contributes to morbidity among socially disadvantaged indigenous adults in central australia. this is largely due to an increased risk of other infections and respiratory disease. the spectrum of htlv-1 related diseases may vary according to the social circumstances of the affected population. © 2014 einsiedel et al.