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Updated: Jan 25, 2026

Interview: HIV-1 Proviral DNA Excision Using an Evolved Recombinase
Published on: June 16, 2008
Revisiting Keratoconjunctivitis sicca associated with Human T-Cell Lymphotropic Virus Type 1: prevalence, clinical
Regina Helena Rathsam-Pinheiro1, Ney Boa-Sorte2, Maria Fernanda Rios Grassi3
1Escola Bahiana de Medicina e Saúde Pública, Centro Integrativo e Interdisciplinar de HTLV, Salvador, BA, Brazil; Instituto Brasileiro de Oftalmologia e Prevenção da Cegueira, Salvador, BA, Brazil.
Background:
The prevalence of keratoconjunctivitis sicca (KCS) associated with Human T-Cell Lymphotropic Virus Type 1 (HTLV-1) (HTLV-1/KCS) has been estimated at around 37%, but its clinical manifestations are poorly described.
Purpose:
To determine the prevalence and associated factors of HTLV-1/KCS in a large cohort of HTLV-1-infected individuals living in Salvador, Brazil.
Methods:
A cross-sectional study was conducted between June 2004 and September 2017 at the Integrative and Multidisciplinary Center for HTLV in Salvador, Bahia-Brazil. Data from 758 HTLV-1-infected patients was collected. A complete ophthalmologic examination was performed in both eyes. Lacrimal function was evaluated by breakup time, Rose Bengal and Schirmer I Tests. KCS diagnosis was considered in the presence of at least two out of three positive tests. HTLV-1 proviral load Crude and Adjusted Prevalence Rates (PR) with 95% Confidence Intervals (95% CI) were estimated using multivariate Poisson Regression with robust error variance.
Results:
The overall prevalence of KCS was 31.7%, with higher rates observed in HTLV-1-associated myelopathy/tropical spastic paraparesis patients (crude PR: 1.84; CI95%: 1.50-2.26) even after adjusting for age, sex, time of HTLV-1 diagnosis and schooling (adjusted PR: 1.63; CI95%: 1.31-2.02). Proviral load, low corrected visual acuity, burning and/or pain and itching were all significantly higher in patients with KCS.
Conclusion:
Burning and/or pain and itching and low corrected visual acuity were the most common alterations of HTLV-1/KCS. High Proviral load was found to be associated with the presence of KCS. It is strongly recommended that HTLV-1 patients undergo periodic ophthalmologic examination to promote the early diagnosis of KCS and prevent the consequences associated with dry eye disease.
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