Jwal B Doctor, Institute of Pharmacy Nirma University, Ahmedabad, Gujarat

Bharat J Kumar, Associate Professor, Dept. of Pediatrics, BJ Medical College, Civil Hospital, Ahmedabad, Gujarat

Abstract

Thyrotoxicosis is infrequently encountered in childhood. The clinical expression is attributed to accelerated metabolism from excessive level of circulating thyroid hormones. We present the case of a 7-year-old female child admitted in Pediatric Ward in Civil Hospital with chief complaint of increased appetite for 6 months and emotional disturbances accompanied by motor hyperactivity for 2 months; child became irritable and easily excitable; failure to thrive, loose stools and increased sweating for 2 months. Clinical signs of goiter, exophthalmos, increased appetite, hyperactivity, tachycardia, increased sweating, weight-15 kg, height-120 cm. Investigations: Hb-10.5 gm%, ESR-26 mm/hr, chest X-ray normal, ECG-sinus tachycardia, ECHO-normal, serum T3-3.46 ng/mL, serum T4-180.0 ng/mL, serum TSH-<0.05 MicroU/mL, TSH-receptor antibody serum by ELISA-28.46 IU/L, USG neck-thyromegaly with bilateral cervical lymphadenopathy. Thyroid scan - findings show bilateral thyromegaly, which increase trapping function in given clinical content. The uptake pattern favors hyperfunction of thyroid gland, possibly Graves’ disease.

Keywords: Failure to thrive, increased sweating, goiter, exophthalmos, increased appetite, hyperactivity, tachycardia, thyroid scan, bilateral thyromegaly

Introduction

Hyperthyroidism refers to increased hormone production by thyroid gland. It is infrequently encountered in childhood with an increase in incidence during adolescence. The clinical manifestations are attributed to accelerated metabolism due to excessive level of thyroid hormones. The most common cause of thyrotoxicosis in children is Graves’ disease (GD), which accounts for 10-15% of childhood thyroid disease in the Western world.

Causes include chronic lymphocytic thyroiditis, excess thyroid hormones ingestion (fictitious thyrotoxicosis), iodine-induced disease, McCune-Albright syndrome or constitutively activated thyrotropin (TSH) receptor. Acute or subacute thyroiditis which tends to transient, TSH secreting pituitary tumors, toxic adenoma, multinodular goiter causing hyperthyroidism are rare in children. One thousand cases of all ages of GD have shown an incidence of 5.7% in children and adolescents. Two large series from India reported an incidence of 3% and 6%, the incidence increasing with age. It is rare before 5 years of age and peaks during adolescence (10-15 years of age). This disease is more common in girls, ratio of girls: boys being 3.1:6.1. Signs of diffuse toxic goiter thyroid eye sign (exophthalmos, lid retraction, lid lag, impaired convergence, ophthalmoplegia), pretibial myxedema observed in GD.

CASE REPORT

A 7-year-old female child was admitted in Pediatric Ward in Civil Hospital with chief complaint of increased appetite for 6 months, emotional disturbances: motor hyperactivity, irritability and easily excitable for 2 months, failure to thrive, loose stools and increased sweating for 2 months. We noticed weight of 15 kg approximately, height of 120 cm, failure to thrive, goiter, exophthalmos (Figs. 1-3), hyperactivity, tachycardia and increased sweating.

On investigation: Hemoglobin (Hb)-10.5 g/dL,erythrocyte sedimentation rate (ESR)-26 mm/hour, chest X-ray was normal, electrocardiogram (ECG) sinus tachycardia, echocardiographic stress (ECHO) was normal, serum T3-3.46 ng/mL, serum T4-180.0 ng/mL, serum TSH-<0.05 microU/mL, TSH-receptor antibody serum by enzyme-linked immunosorbent assay (ELISA)-28.46 IU/L. Ultrasonography (USG) neck-thyromegaly with bilateral cervical lymphadenopathy, thyroid scan - findings show bilateral thyromegaly, which increase trapping function in given clinical content. The uptake pattern favors hyperfunction of thyroid gland, possibly GD.

Diagnosis

The total T3 and T4 levels are elevated with suppressed TSH. The thyroid receptor antibody (TRAb) is positive in more than 90% of children with GD.

Management and Outcome

The treatment modality consists of medical management with antithyroid drug, radioactive iodine ablation or surgery. Medical management keeps thyroid hormone levels within normal range till natural remission occurs. The other two modalities of treatment result in thyroid gland ablation and bring relief. Medical management is preferred in children. Medical therapy consists of propylthiouracil, methimazole and carbimazole.

Improvement starts around 2 weeks and it may take as much as 6-8 weeks before hormone level T3 and T4 are normalized. b blocker propranolol 0.5-2.0 mg/kg/day8-hour dose was given for about 1 month for marked palpitation tremors. Monitoring of white blood cell (WBC) count was done during antithyroid drug therapy. Lower dose of irradiation is associated with future malignancy and hence higher and single dose are recommended. Surgical therapy with total thyroidectomy offers the most rapid resolution of thyrotoxicosis and is indicated when the goiter is too large.

Suggested Reading

1. Desai MP, Menon PSN, Bhatia V (Eds.). Pediatric Endocrine Disorders, 3rd Edition. Himayantnagar, Hyderabad: Bookcraft Publishing Private Limited; 2014. pp. 211-4.
2. Lazar L, Kalter-Leibovici O, Pertzelan A, Weintrob N, Josefsberg Z, Phillip M. Thyrotoxicosis in prepubertal children compared with pubertal and postpubertal patients. J Clin Endocrinol Metab. 2000;85(10):3678-82.
3.  LaFranchi SH. Hyperthyroidism in the neonatal and childhood. Werner and Ingbara acquired hyperthyroidism in the thyroid a fundamental and clinical text. 2013;10:803-14.
4. Kraem Z. Grave disease in the children. J Pediatr Endocrinol Metab. 2001;13:229-33.
5. Lee JA, Grumbach MM, Clark OH. The optimal treatment for paediatric Graves’ disease is surgery. J Clin Endocrinol Metab. 2007;92(3):801-3.
6. Rivkees SA, Dinauer C. An optimal treatment for paediatrics Graves’ disease in radioiodine. J Clin Endocrinol Metab. 2007;92(3):797-800.
7. Bauer AJ. Approach to paediatric patients with Grave disease: what is definitive therapy warranted? J Clin Endocrinol Metab. 2011;96(3):580-8.
8. Zimmerman D, Lteif AN. Thyrotoxicosis in children. Endocrinol Metab Clin North Am. 1998;27(1):109-26.
9. Desai MP. Disorders of thyroid gland in India. Indian J Pediatr. 1997;64(1):11-20.