Pulmonary Disease Is Associated With Human T-Cell Leukemia Virus Type 1c Infection: A Cross-sectional Survey in Remote Aboriginal Communities.

BACKGROUND: The human T-cell leukemia virus type 1 (HTLV-1) subtype c is endemic to central Australia. We report the first large-scale, community-based, health survey of HTLV-1 and its disease associations in this setting. METHODS: Aboriginal community residents aged >2 years in 7 remote communities were invited to do a health survey that included a questionnaire, spirometry, and clinical examination by a physician blinded to HTLV-1 status, clinical records, and spirometry results. Blood was drawn for HTLV-1 serology and proviral load (PVL). Pulmonary disease was assessed clinically and spirometrically and, where records were available, radiologically after the clinical assessment. Associations between specific diseases and HTLV-1 status were determined using logistic regression, adjusting for available confounders. RESULTS: Overall, 579 residents (164 children aged 3-17 years; 415 adults) were examined (37.7% of the estimated resident population). HTLV-1 prevalences for children and adults were 6.1% and 39.3%, respectively. No associations were found between HTLV-1 and any assessed clinical condition among children. Chronic pulmonary disease and gait abnormalities were more common among adults with HTLV-1 infection. Adjusted odds ratios among participants with PVL ≥1000 per 105 peripheral blood leukocytes were 7.08 (95% confidence interval [CI], 2.67-18.74; P < .001), 9.81 (95% CI, 3.52-27.35; P < .001), and 14.4 (95% CI, 4.99-41.69; P < .001) for clinically defined chronic pulmonary disease, moderate-severe expiratory airflow limitation, and radiologically determined bronchiectasis/bronchiolitis, respectively, and 5.21 (95% CI, 1.50-18.07; P = .009) for gait abnormalities. CONCLUSIONS: In the first study of HTLV-1 disease associations based on community recruitment and blinded assessment, HTLV-1 infection was strongly associated with pulmonary disease and gait abnormalities.

Higher human T-cell leukaemia virus type 1 (HTLV-1) proviral load is associated with end-stage kidney disease in Indigenous Australians: Results of a case-control study in central Australia.

Case series suggest that human T-cell leukaemia virus type 1 (HTLV-1) is associated with kidney disease; however, little is known about the impact of proviral load (PVL). The present study was commenced to determine whether higher HTLV-1 PVL is associated with end stage kidney disease (ESKD) in Indigenous Australians. A case-control study was conducted in Alice Springs Hospital (ASH), 1 July 2007 to 30 November 2015. Cases included all 80 Indigenous adults (>17 years) with HTLV-1c and ESKD, matched 1:1 by sex to controls with HTLV-1 who had no renal disease or other recognised disease associations of HTLV-1, and were recruited during the same period. The association between PVL and ESKD was assessed using logistic regression. Median (IQR) HTLV-1c PVL for subjects with ESKD (6.86, IQR (3.35, 8.23) log copies per 105 peripheral blood leukocytes (PBL) (ie, 0.95; IQR, 0.03; 3.70% PBL) was significantly higher than that of the asymptomatic group (3.47; IQR (-0.04, 6.61) log copies per 10 5 PBL (ie, 0.01; IQR, 0.00; 0.52% PBL) (asymptomatic vs ESKD, P (ranksum) < .001). Major factors associated with ESKD were diabetes (adjusted odds ratio [aOR], 21.80; 95% CI, 4.84, 98.22; P < .001), hypertension (aOR, 4.16; 1.11, 15.64; P = .03), remote residence (aOR, 5.34; 95% CI, 1.17, 27.29; P = .03) and HTLV-1c PVL greater than or equal to 100 copies per 10 5 PBL (aOR, 3.67; 95% CI, 1.36, 9.92; P = .01). Higher HTLV-1c PVL are strongly associated with inflammatory diseases. The high HTLV-1c PVL reported here may have clinical implications for people with HTLV-1 who require haemodialysis. Longitudinal studies are required to determine whether this association is causal.