Down syndrome, insulin-dependent diabetes mellitus and hyperthyroidism: a rare association

Area of Science:

• Pediatric Endocrinology
• Genetics
• Autoimmunology

Background:

• Down syndrome (DS) is associated with an increased risk of autoimmune endocrinopathies.
• Autoimmune disorders in DS often increase with age and can predispose to other conditions.
• Simultaneous onset of type 1 diabetes mellitus and hyperthyroidism is rare in children with DS.

Observation:

• An 8-year-old girl with DS presented with hyperglycemia and ketosis, indicative of type 1 diabetes mellitus.
• During initial investigations for diabetes, hyperthyroidism was detected.
• Laboratory results showed suppressed thyroid-stimulating hormone (<0.01 µUI/mL), positive antithyroid antibodies, and thyroid gland enlargement on ultrasound.

Findings:

• The case demonstrates the concurrent presentation of type 1 diabetes mellitus and hyperthyroidism in a child with Down syndrome.
• This co-occurrence underscores the complex interplay of autoimmune conditions in individuals with DS.
• Early detection of hyperthyroidism was achieved through routine monitoring during diabetes diagnosis.

Implications:

• Routine thyroid function monitoring is crucial at the time of diabetes diagnosis in children with Down syndrome, even without overt symptoms.
• This case alerts healthcare providers to the potential for simultaneous autoimmune endocrine dysfunction in pediatric DS patients.
• Prompt identification and management of co-existing endocrinopathies can improve patient outcomes in this vulnerable population.