Thyroid dysfunction in antiretroviral treated children

BACKGROUND: A high rate of thyroid disorders has been described in HIV-infected adults treated with highly active antiretroviral therapy (HAART), but data on children are lacking. We aimed to assess thyroid function in pediatric patients. METHODS: Fifty-two HIV-infected children receiving HAART were assessed for signs of thyroid dysfunction and serum concentrations of thyrotropin (TSH), free thyroxin (FT4), free triiodothyronine (FT3), thyroglobulin (TG), reverse triiodothyronine (rT3), anti-TG and antimicrosomal (anti-TSM) antibodies. RESULTS: Eighteen (35%) children showed thyroid abnormalities: isolated low FT4 value in 16; subclinical hypothyroidism in 1; and symptomatic hypothyroidism in 1.Children with low FT4 values as compared with the 34 children without thyroid dysfunction were similar for stage of disease, number of patients with undetectable HIV-RNA, FT3, TSH, TG, rT3, anti-TSM and anti-TG values, whereas they had shorter duration of HAART exposure (P = 0.019) and lower CD4 cell percentage (P = 0.035). The thyrotropin-releasing hormone (TRH) test was normal in all children with low FT4 values. Among children with low FT4, FT4 concentrations correlated positively with CD4 cell percentage (P < 0.05) and duration of HAART exposure (P < 0.05).The case with subclinical hypothyroidism had high basal TSH (7.3 microunits/ml), normal TSH response to TRH test and normal FT4, FT3, TG, rT3, anti-TG and anti-TSM antibodies.The case with symptomatic hypothyroidism had low FT4 (6.6 pg/ml) and high TSH (44 microunits/ml), TG (55 ng/ml), anti-TG (666 IU/ml) and anti-TSM (123 IU/ml). CONCLUSION: Thyroid abnormalities occur frequently in HAART-treated children even in the absence of clinical symptoms. These data suggest a need of regular thyroid function monitoring.