THYROID-DYSFUNCTION IN HIV-INFECTED CHILDREN - IS L-THYROXINE THERAPYBENEFICIAL

Purpose. To assess thyroid function in symptomatic HIV-infected infant s and children with failure to thrive and to evaluate clinical respons e in patients with hyperthyrotropinemia to levothyroxine. Methods. We evaluated 11 children (mean age: 1.5 years; males = 5, females = 6) wi th HIV infection and failure to thrive (weight and height > 2 SD below the mean) for presence of hypothyroidism. Thyroid-stimulating hormone (TSH) and thyroxine (T4) were measured. Four children with high basal TSH and one child with a normal basal TSH underwent the Thyrotropin-r eleasing hormone (TRH) stimulation test as well. Four children receive d treatment with L-thyroxine. Results. Eight of the 11 children had hi gh basal TSH levels. All patients had normal or increased T4 values. T he TRH stimulation test showed an exaggerated response in all four pat ients with high basal TSH values and a normal response in one patient with normal basal THS values. All four patients who received treatment with L-thyroxine showed normalization of the TSH. Increased growth ve locity was noted in 3 of 4 patients. The fourth patient died within tw o weeks following initiation of therapy for overwhelming candida sepsi s. The autopsy of this patient showed atrophy of the thyroid gland. Tw o of the four patients with high TSH levels, who did not receive L-thy roxine, died; the other two did not show any improvement in their heig ht z scores. Two patients with a high TSH also had high thyroid-bindin g hormone (TBG) levels. Both patients with the high TBG died within 2 to 3 months of the study. Conclusions. Hypothyroidism as indicated by elevated basal TSH and abnormal TRH response was common in the HIV-inf ected children in this study and may have contributed to failure of gr owth in these children. Replacement therapy resulted in correction of abnormal TSH and improvement of height z scores during the period of o bservation. The significance of these findings needs to be confirmed i n a larger prospective study.