Severe Acquired Primary Hypothyroidism in Children and its Influence on Growth: A Retrospective Analysis of 43 Cases.

INTRODUCTION Severe acquired hypothyroidism in childhood is a rare condition, mostly caused by autoimmune thyroiditis. Scarce and inconsistent data based on small patient numbers exist concerning its impact on growth in height. METHODS Patient files at a single centre university hospital over 8 years were retrospectively reviewed. We identified 43 patients (mean age 10.6 years, 3.3-15.25, 59% prepubertal, 88% females) in a cohort of children older than 3 years with an initial TSH>30 mIU/l and reduced T4 or fT4; congenital and drug-induced hypothyroidism were excluded. RESULTS All patients had signs of autoimmune thyroiditis (93% positive autoantibodies, 95% typical ultrasonography, 63% goiter). Median TSH was 100 mIU/l [0.3-4 mIU/l]), median fT4 3.55 pg/ml [8-19 pg/ml], median T4 2.85 µg/dl [5.3-11 µg/dl]. Presenting symptoms included goiter (26%), tiredness (23%), weight gain (19%), and growth retardation (19%). The diagnosis was made incidentally in 26% patients. In 75% growth was retarded (median height standard deviation score (SDS)-0.55), in 17% height SDS was<-2 at diagnosis. Midparental height SDS at diagnosis correlated significantly with T4 and fT4 (r=0.77, p=0.0012 and r=0.53, p=0.021 respectively). Catch-up growth under T4 substitution was significantly greater in prepubertal than in pubertal children (p 0.049). CONCLUSION This so far largest pediatric cohort with severe acquired hypothyroidism confirms a serious impact on growth which, however in most cases, showed a certain catch-up growth after adequate L-thyroxine therapy. The pubertal state seems to be important for catch-up growth. A significant number of patients were not diagnosed clinically, although affected by severe hypothyroidism.

[1]  A. Kucharska,et al.  Clinical and Biochemical Characteristics of Severe Hypothyroidism Due to Autoimmune Thyroiditis in Children , 2020, Frontiers in Endocrinology.

[2]  AversaTommaso,et al.  Five-Year Prospective Evaluation of Thyroid Function Test Evolution in Children with Hashimoto's Thyroiditis Presenting with Either Euthyroidism or Subclinical Hypothyroidism , 2016 .

[3]  Jennifer Vredeveld,et al.  Iodine Deficiency and Hypothyroidism From Voluntary Diet Restrictions in the US: Case Reports , 2016, Pediatrics.

[4]  A. Mussa,et al.  Thyroid Function Patterns at Hashimoto’s Thyroiditis Presentation in Childhood and Adolescence Are Mainly Conditioned by Patients’ Age , 2012, Hormone Research in Paediatrics.

[5]  M. Vakaki,et al.  Epidemiological characteristics of children with autoimmune thyroid disease , 2011, Hormones.

[6]  A. Alikaşifoğlu,et al.  Assessment of thyroid function during the long course of Hashimoto's thyroiditis in children and adolescents , 2009, Clinical endocrinology.

[7]  A. Grüters,et al.  Small thyroid volumes and normal iodine excretion in Berlin schoolchildren indicate full normalization of iodine supply. , 2009, Experimental and clinical endocrinology & diabetes : official journal, German Society of Endocrinology [and] German Diabetes Association.

[8]  M. Lakomek,et al.  Autoimmune thyreoiditis in childhood--epidemiology, clinical and laboratory findings in 61 patients. , 2009, Experimental and clinical endocrinology & diabetes : official journal, German Society of Endocrinology [and] German Diabetes Association.

[9]  A. McGrogan,et al.  The incidence of autoimmune thyroid disease: a systematic review of the literature , 2008, Clinical endocrinology.

[10]  M. Chhillar,et al.  Goitrous Autoimmune Thyroiditis in a Pediatric Population: A Longitudinal Study , 2008, Pediatrics.

[11]  M. Phillip,et al.  Chronic autoimmune thyroiditis in children and adolescents: at presentation and during long-term follow-up , 2008, Archives of Disease in Childhood.

[12]  H. Dörr,et al.  Verlauf, Therapie und Komorbidität bei Hashimoto-Thyreoiditis im Kindesalter , 2003, Monatsschrift Kinderheilkunde.

[13]  N. Tandon,et al.  Hashimoto's thyroiditis: countrywide screening of goitrous healthy young girls in postiodization phase in India. , 2000, The Journal of clinical endocrinology and metabolism.

[14]  T. MacDonald,et al.  Prevalence and aetiology of hypothyroidism in the young , 2000, Archives of disease in childhood.

[15]  M. Ranke,et al.  Catch-Up Growth after Childhood-Onset Substitution in Primary Hypothyroidism: Is It a Guide towards Optimal Growth Hormone Treatment in Idiopathic Growth Hormone Deficiency? , 1998, Hormone Research in Paediatrics.

[16]  P. Beeson Age and sex associations of 40 autoimmune diseases. , 1994, The American journal of medicine.

[17]  K. Copeland,et al.  Brief report: hypothyroidism caused by chronic autoimmune thyroiditis in very young infants. , 1994, The New England journal of medicine.

[18]  Zusammenfassung,et al.  Longitudinale Körperentwicklung gesunder Kinder von 0 bis 18 Jahren , 1992 .

[19]  M. Preece,et al.  Growth prognosis and growth after menarche in primary hypothyroidism. , 1991, Archives of disease in childhood.

[20]  S. Rivkees,et al.  Long-term growth in juvenile acquired hypothyroidism: the failure to achieve normal adult stature. , 1987, The New England journal of medicine.

[21]  M. Inoue,et al.  High incidence of chronic lymphocytic thyroiditis in apparently healthy school children: epidemiological and clinical study. , 1975, Endocrinologia japonica.

[22]  F. H. Tyler,et al.  Occurrence and natural history of chronic lymphocytic thyroiditis in childhood. , 1975, The Journal of pediatrics.

[23]  M. Salerno,et al.  Five-Year Prospective Evaluation of Thyroid Function Test Evolution in Children with Hashimoto's Thyroiditis Presenting with Either Euthyroidism or Subclinical Hypothyroidism. , 2016, Thyroid : official journal of the American Thyroid Association.

[24]  U. Zaleska-Dorobisz,et al.  Chronic autoimmune thyroid disease in children and adolescents in the years 1999-2004 in Lower Silesia, Poland. , 2005, Hormones.

[25]  J. Heinrich,et al.  Final Height in Long-term Primary Hypothyroid Children , 1998, Journal of pediatric endocrinology & metabolism : JPEM.

[26]  S. Lafranchi Thyroiditis and acquired hypothyroidism. , 1992, Pediatric annals.

[27]  G. Van Oost,et al.  [Longitudinal physical development of healthy children 0 to 18 years of age. Body length/height, body weight and growth velocity]. , 1992, Klinische Padiatrie.