Changes in the thyroid hormone profiles in children with nephrotic syndrome.

PURPOSE

We compared thyroid hormone profiles in children with nephrotic syndrome (NS) during the nephrotic phase and after remission.

METHODS

This study included 31 pediatric NS patients. The thyroid hormone profiles included serum levels of triiodothyronine (T3), thyroxine (T4), thyroid-stimulating hormone (TSH), and free T4.

RESULTS

Of the 31 patients, 16 (51.6%) showed abnormal thyroid hormone profiles: 6 had overt hypothyroidism, 8 had subclinical hypothyroidism, and 2 had low T3 syndrome. The mean serum T3, T4, and free T4 levels in the nephrotic phase and after remission were 82.37±23.64 and 117.88±29.49 ng/dL, 5.47±1.14 and 7.91±1.56 µg/dL, and 1.02±0.26 and 1.38±0.23 ng/dL, respectively; the levels were significantly lower in the NS nephrotic phase (P=0.0007, P<0.0001, and P=0.0002). The mean serum TSH levels during the nephrotic phase and after remission were 8.05±3.53 and 4.08±2.05 µIU/ mL, respectively; they were significantly higher in the nephrotic phase (P=0.0005). The urinary protein/ creatinine ratio during the nephrotic phase was significantly correlated with serum T3, T4, and free T4 levels (r=-0.5995, P=0.0032; r=-0.5797, P=0.0047; r=-0.5513, P=0.0078) as well as with TSH levels (r=0.5022, P=0.0172). A significant correlation was found between serum albumin and serum T3 levels during the nephrotic phase (r=0.5385, P=0.0018) but not between serum albumin and T4, TSH, or free T4 levels. These significant correlations all disappeared after remission.

CONCLUSION

Abnormal thyroid hormone profile findings were observed in 51.6% of pediatric patients with NS. Thyroid hormone levels normalized after remission, regardless of levothyroxine therapy.