Serum creatine kinase activity in untreated primary hypothyroid children

Objectives To determine association between primary

hypothyroidism and serum creatine kinase (CK) activity

in children.

Design and Setting Prospective study of patients seen

at university paediatric unit, Galle for a period of 4

years starting from January 1998.

Method Primary hypothyroidism was confirmed by

presence of elevated serum thyroid stimulating hormone

and low thyroxine for age. All newly diagnosed patients

with primary hypothyroidism were tested for serum CK

activity. Levels were compared with serum CK activity

in normal euthyroid children. Serum CK levels were

repeated 6 weeks after starting thyroxine therapy.

Results 19 children presented with primary

hypothyroidism during study period. All had elevated

serum CK levels. 2 patients showed clinical evidence

of muscular hypertrophy. There were 7 neonates with

congenital hypothyroidism.

Conclusions: Elevated levels of CK activity were

seen in all children with untreated primary

hypothyroidism in this series. CK activity became

normal 4-6 weeks after starting therapy. Hence

elevated serum CK could be used as an indicator for

diagnosis of untreated hypothyroidism or to assess

adequacy of therapy in primary hypothyroidism.

Sri Lanka Journal of Child Health, 2004; 33: 106-7

(Key words: Creatine kinase, primary hypothyroidism, Kocher-Debre-Semelaigne syndrome)

doi: 10.4038/sljch.v33i4.620