title: Hypothyroidism in children with cystinosis.
abstract: Eight children with cystinosis (3 with renal transplants, 2 on maintenance haemodialysis, 2 with chronic renal failure, and one with normal renal function) were studied for evidence of hypothyroidism, and compared with a control group of children with chronic renal failure due to other causes. Abnormal thyroid function was present in all the cystinotic patients: thyroxine (T4) low in 1, free thyroxine index (FTI) low in 2, thyroid-stimulating hormone (TSH) raised in 6; all had a supranormal TSH response to thyrotrophin-releasing hormone (TRH) stimulation, indicating impaired thyroid reserve compared with patients in the control group who had a depressed or normal TSH response. Increased growth velocity with thyroid supplementation occurred in only 2 patients, and the onset of puberty may have contributed to this improvement. Hypothyroidism is a common finding in cystinosis, and it is suggested that thyroxine treatment be started when the TSH concentration becomes raised.
mesh_terms: D000293:Adolescent; D002648:Child; D002675:Child, Preschool; D003554:Cystinosis / Q000097:blood / Q000150:complications*; D006801:Humans; D007037:Hypothyroidism / Q000188:drug therapy / Q000209:etiology*; D007676:Kidney Failure, Chronic / Q000150:complications; D013972:Thyrotropin / Q000097:blood; D013974:Thyroxine / Q000097:blood / Q000627:therapeutic use; D014284:Triiodothyronine / Q000097:blood
chemical_list: D014284:Triiodothyronine; D013972:Thyrotropin; D013974:Thyroxine