Symptomatic Hypocalcemia due to Nutritional Vitamin D Deficiency in Three Adolescents during the COVID-19 Pandemic.

Background: Symptomatic hypocalcemia secondary to vitamin D deficiency (VDD) is rare among adolescents without underlying medical disorders, but its prevalence is higher in known risk populations. We report on three adolescent males with low nutritional intake of vitamin D and calcium and limited sun exposure who presented with hypocalcemic tetany and muscle cramps due to VDD during the COVID-19 pandemic. Case Reports. Three adolescent males (age range 14 to 16 years) presented with symptomatic hypocalcemia: paresthesia, carpopedal spasms, and muscle cramps. All reported limited dairy intake and sun exposure. Laboratory studies showed mean ionized calcium (iCa) 2.73 mg/dl (range 2.69-2.8), mean phosphorus 4.17 mg/dl (range, 3-5.4), mean parathyroid hormone (PTH) 431.67 pg/mL (range, 320-527), and mean 25-hydroxyvitamin D (25(OH)D) 7.37 ng/mL (range 5.3-10.8). All the patients presented during the COVID-19 pandemic, and one had COVID-19 infection. All were treated with oral calcium and high dose ergocalciferol. Patients 2 and 3 were also treated with intravenous calcium gluconate infusion and oral calcitriol. Conclusion: Severe VDD with symptomatic hypocalcemia can occur among adolescents without underlying medical diagnoses due to dietary and behavioral habits that limit nutritional intake and sun exposure. Risk factors of the patients may have been potentiated by pandemic-related behaviors such as more time indoors at home related to social distancing, as well as diets with limited nutrient intake. Adolescents presenting with nonspecific musculoskeletal symptoms should be screened for VDD and hypocalcemia. Appropriate treatment and preventive measures can stop immediate and long-term complications.

Severe Hypothyroidism and Large Goiter due to Iodine Deficiency in an Adolescent Male in the United States: A Case Report and Review of the Literature.

Acquired hypothyroidism due to iodine deficiency is extremely rare in the United States due to the introduction of table salt iodization in the 1920s (Leung et al., 2012). We present the case of an adolescent male with a history of mild autism spectrum disorder and an extremely restrictive diet who was found to have iodine deficiency as the etiology for his rapidly enlarging goiter and antibody-negative hypothyroidism. Thyroid-stimulating hormone (TSH) was 416 µIU/mL (0.350-5.500 µIU/mL), free thyroxine (T4) was <0.1 ng/dL (0.80-1.80 ng/dL), and triiodothyronine (T3) was 41 ng/dL (82-213 mg/dL) at diagnosis. The patient's 24-hour urinary iodine was undetectable. He was started on iodine supplementation with rapid visible improvement of goiter within two weeks and normalization of thyroid function tests within four weeks. Thorough dietary history and nutritional screening are important in cases of acquired hypothyroidism and/or goiter. Alternatively, diets that are low in iodized salt, dairy, bread, and seafood should raise concern for iodine deficiency, and patients with suspected or proven iodine deficiency should be screened for hypothyroidism.

Thyroid function tests of iodine deficiency goiter can mimic thyroid hormone resistance alpha.

OBJECTIVES: Iodine deficiency goiter can develop in children on a restrictive diet and most have normal thyroid function. We report a 6-year-old girl with iodine deficiency goiter with thyroid function studies mimicking thyroid hormone resistance alpha. Thyroid hormones mediate its effects through thyroid hormone receptors alpha and beta. Biochemical picture of low/low-normal T4 and high/high-normal T3 levels, variably reduced reverse T3 and normal TSH is characteristic of thyroid hormone resistance alpha. CASE PRESENTATION: A 6-year-old girl, born out of non-consanguineous marriage presented with goiter of 1.5 years duration. She was without symptoms of thyroid dysfunction. The patient was evaluated at one year of age for macrocephaly with cranial ultrasound which was normal. She had normal growth and development. Patient was vegan and was not on any medications or supplements. Laboratory work up showed TSH 5.03 uIU/mL (0.34-5.5), FT4 0.3 ng/dL (0.58-1.2), FT3 5.3 pg/mL (2.5-3.9), total T3 258 ng/dL (94-241), reverse T3 <5.0 ng/dL (8.3-22.9) and negative thyroglobulin antibody and thyroid peroxidase antibody. Thyroglobulin level was 1,098.8 ng/mL (<13 ug/L), and urine iodine 15.8 ug/L (<100 ug/L) confirming a diagnosis of iodine deficiency goiter. Patient was started on iodine supplements, 150 ug daily and repeat work up 3 months later were TSH: 2.717 uIU/mL, T3, total 182 ng/dL, T4, total 9.3 ug/dL, FT 4 2.1 ng/dL. CONCLUSIONS: Iodine deficiency goiter may present with low FT 4, elevated T3 and normal TSH mimicking thyroid hormone resistance alpha and should be considered in children on restrictive diet.