Y Najam1, M Khan, F Ilahi, A Alam. 1. Department of Pediatrics, Shifa International Hospital, Islamabad.
Abstract
OBJECTIVE: To evaluate the distribution of Thyroxin (T4) and Thyroid Stimulating Hormone (TSH) values in children of various age groups attending our hospital. METHOD: We have retrospectively reviewed the T4, TSH levels recorded at our hospital in children from birth to 5 years and evaluated the reference intervals for T4 TSH amongst different ages. Non parametric methods were used to establish a 97.5th, 95th, 50th, 5th and 2.5th centiles. RESULTS: In T4 (n=1148) and TSH (n=1142) samples reviewed a TSH surge following delivery showed a sharp decline in the first 4 days of life. This was followed by a more gradual downward trend. Data on T4 estimations showed a similar but more gradual downward trend in advancing age groups. The 5th-95th centile reference range for TSH showed values between 1.7-22.5 (0-4 days; n=992), 0.6-13.3 (5-7 days; n=38), 0.9-14.0 (1 week-1 month; n=38), 0.5-13.6 (1 month-1 year, n=38) and 0.4-12.8 (1-5 years; n=38) microlU/mL. The 5th-95th centile reference range for T4 showed values between 10.7-25.0 (0-4 days; n=995), 6.5-20.4 (5-7 days; n=35), 8.0-18.1 (1 week-1 month; n=38), 6.0-16.1 (1 month-1 year; n=41), 6.9-15.3 (1-5 years; n=39) micro gm/dl. CONCLUSION: We recommend using separate T4 and TSH reference values for children in different age groups. Further large-scale studies should be done in Pakistan to establish these reference values within age groups. A national center for neonatal thyroid screening is highly recommended.
OBJECTIVE: To evaluate the distribution of Thyroxin (T4) and Thyroid Stimulating Hormone (TSH) values in children of various age groups attending our hospital. METHOD: We have retrospectively reviewed the T4, TSH levels recorded at our hospital in children from birth to 5 years and evaluated the reference intervals for T4 TSH amongst different ages. Non parametric methods were used to establish a 97.5th, 95th, 50th, 5th and 2.5th centiles. RESULTS: In T4 (n=1148) and TSH (n=1142) samples reviewed a TSH surge following delivery showed a sharp decline in the first 4 days of life. This was followed by a more gradual downward trend. Data on T4 estimations showed a similar but more gradual downward trend in advancing age groups. The 5th-95th centile reference range for TSH showed values between 1.7-22.5 (0-4 days; n=992), 0.6-13.3 (5-7 days; n=38), 0.9-14.0 (1 week-1 month; n=38), 0.5-13.6 (1 month-1 year, n=38) and 0.4-12.8 (1-5 years; n=38) microlU/mL. The 5th-95th centile reference range for T4 showed values between 10.7-25.0 (0-4 days; n=995), 6.5-20.4 (5-7 days; n=35), 8.0-18.1 (1 week-1 month; n=38), 6.0-16.1 (1 month-1 year; n=41), 6.9-15.3 (1-5 years; n=39) micro gm/dl. CONCLUSION: We recommend using separate T4 and TSH reference values for children in different age groups. Further large-scale studies should be done in Pakistan to establish these reference values within age groups. A national center for neonatal thyroid screening is highly recommended.