ABSTRACT
Background: Hypothyroidism is a common endocrinal cause of growth retardation in children. Following adequate treatment with thyroxine, growth resumes at an accelerated rate which is known as catch-up growth. There are few observational studies from India on the growth parameters following treatment with thyroxine in children with hypothyroidism.Methods: A retrospective study was done in children aged 2-10 years who were newly diagnosed cases of primary hypothyroidism [Total serum Thyroxine (T4) levels <5 'g/dl and serum Thyroid Stimulating Hormone (TSH) levels ?15 'U/ml] and treated with oral thyroxine to attain euthyroid state. Height measured before starting treatment and at the time of follow up visits was noted, the Height Standard Deviation Scores (HSDS) were calculated. The effect of thyroxine on linear growth was studied.Results: There were 23 children who were diagnosed as having primary hypothyroidism of whom 16(69.6%) were females and 7(30.4%) were males. The mean age of the children studied was 7.3'2.3 years. The mean dose of thyroxine required to maintain euthyroid status was 4.6'2.2 'g/kg/day. Mean duration of follow up was 13.7'2.4 months. The initial HSDS was - 2.31'0.9 which improved to a final value of - 1.7'0.76 (?HSDS0.61, p value <0.0001). Mean height velocity was 8.1 cms/year.Conclusions: Following adequate thyroxine replacement therapy catch-up growth occurs and increased growth velocity leads to partial regain of height deficit in the first couple of years of treatment.
ABSTRACT
Objective To analyze the distribution of common chromosomal karyotypes of patients with Turner syndrome (TS), and to explore the correlation between the age and height standard deviation scores (HSDS) on diagnosis.Methods Retrospective investigation was performed for the data of age and HSDS on diagnosis in 273 TS girls(≤ 18.0 years old)diagnosed by chromosomal karyotypes.The main statistical methods were analyzed with t-test and Pearson correlation test by using the SPSS 18.0 statistical software.Results (1) There were 4 kinds of common chromosomal karyotypes in the TS :45, X (87/273 cases,31.9％),46, X, i (Xq) (43/273 cases, 15.7％) ,45, X/46, X, i (Xq) (36/273 cases, 13.2％) and 45, X/46, XX (23/273 cases, 8.4％), respectively, the adolescent TS all had delayed puberty.For the cases with 45, X karyotypes ,3 cases presented mental retardation and 2 cases with organs deformity.(2)The patients with 45 ,X/46,X,i(Xq) karyotypes or with 46,X,i(Xq) karyotypes had the maximum(12.56 age) or the minimum(9.70 age) mean age on diagnosis, respectively, there was a significant difference between 2 groups (t =3.019, P =0.004).The maximum deviation from normal height was found in the patients with karyotypes of 46, X,i (Xq) (HSDS =-4.04), and the minimum deviation was in the patients with karyotypes of 45,X/46, XX (HSDS =-3.16), and there was a significant difference between 2 groups (t =-2.95, P =0.004).(3) More than 75.7％ of TS patients was diagnosed when their heights deviated above 3 SD,and their mean age on diagnosis was 12.10 age,which was 3 years later than those patients within 2 SD.(4) There was a significant negative correlation between the age and HSDS on diagnosis in the groups of common chromosomal karyotypes[45,X、46,X,i(Xq) and 45,X/46,XX] (r =-0.551,-0.560,-0.622,all P ＜ 0.01), except for the group with the 45, X/46, X, i (Xq).Conclusions (1) In this study, the consti-tuent ratios of these 4 common chromosomal karyotypes were different from those in Europe and America's.(2)Patients with 45 ,X may have more severe symptoms than others.(3)The mean age on diagnosis was at least 3.0 years earlier when considered HSDS below-2.00 as an indicator for chromosomal karyotype screening,which would facilitate earlier diagnosis.