Masks of severe acquired hypothyroidism in preschool children

We describe two cases of severe acquired hypothyroidism associated with autoimmune thyroiditis in preschool children. Hypothyroidism was masked by pericarditis in the first case and by polyarthritis in the second case. Both patients presented with the full-blown clinical picture of hypothyroidism in the form of increased fatigue and drowsiness, a pale and pasty skin, overweight, constipation, marked hypercholesterolemia, anemia, and an increased and indurated thyroid. In both cases, diagnosis of hypothyroidism was performed after consultation of the endocrinologist for overweight/obesity. Finally, the relationship between cardiac and joint changes and hypothyroidism was confirmed by positive changes in clinical and laboratory-instrumental data in the course of levothyroxine therapy and by follow-up results of patients. The presented cases indicate the need for timely diagnosis of hypothyroidism that may be a potential cause of pericarditis and polyarthritis in children.