A study of thyroid dysfunction in HIV infected patients in a tertiary care hospital

Abstract

Background: Increasing prevalence of thyroid dysfunction has been reported in HIV-infected patients. However, there is insufficient evidence to recommend routine thyroid screening of asymptomatic individuals. Hence, this study was undertaken in an attempt to resolve these issues. Methods: A cross sectional prevalence study was conducted on 75 adult HIV positive patients who did not suffer from hypertension, diabetes, coronary artery disease or thyroid disorder. A detailed history taking and examination was done and biochemical, microbiological and radiological tests were performed in order to reach a diagnosis. In addition, FT3, FT4, TSH and CD4 were done in all the patients. Results: Overt hypothyroidism was found in 2 (3%), subclinical hypothyroidism in 10 (13%), isolated low FT4 in 2 (3%) and sick euthyroidism in 19 (25%) patients. As the stage of HIV advanced, the FT3 and FT4 levels went on decreasing. The TSH levels however, did not correlate with the stage of infection. A direct correlation was found between FT3 and CD4 counts and an inverse correlation between TSH levels and CD4 counts. The mean TSH levels in patients on HAART were significantly higher than in patients not on HAART. Cryptococcal meningitis was found to be associated with subclinical hypothyroidism, CNS toxoplasmosis with isolated low FT4 levels and tuberculosis with sick euthyroidism. Conclusions: Thyroid dysfunction in HIV infected patients was largely asymptomatic. There was a direct correlation between WHO clinical stage of infection and serum FT3 and FT4 levels. TSH levels increased as CD4 counts decreased. Patients on HAART had a high prevalence of subclinical hypothyroidism. No association could be implied between opportunistic infections (OIs) and thyroid dysfunction, due to a small sample size.