ESPE Abstracts

An 11-year-old female presents with a 6-week history of double and blurred vision associated with headaches and neck swelling. Thyroid function tests demonstrated antibody negative hypothyroidism and connective tissue disorder screening was negative. The patient was commenced on thyroid hormone replacement (levothyroxine). 5 days later, she re-presented with strabismus and progressive diplopia. Intracranial imaging was performed to rule out space occupying masses. A diagnosis of left sided Brown’s syndrome secondary to hypothyroidism was made. Initial treatment consisted of conservative management with a Fresnel prism whilst continuing levothyroxine to reach euthyroid status. Patient has remained clinically stable since presentation with no further recurrence of symptoms. Further tests after her first presentation included thyroid antibody and connective tissue disorder screening, an adrenocorticotrophin stimulating test and glucose levels which were all normal. Importantly, anti-thyroid peroxidase antibodies were not detected. An ultrasound scan described findings consistent with a diffuse goitre. Computerised tomography performed at the time of her second presentation and a follow-up magnetic resonance image of the brain was reported as normal with no evidence of a mass lesion. Specifically, there were normal appearances of the extra-ocular muscles. A repeat thyroid ultrasound 3 years 8 months from first presentation demonstrated a mildly enlarged thyroid gland with a heterogenous texture and increased vascularity consistent with thyroiditis. Brown’s syndrome is characterised by the inability to elevate the affected eye in adduction due to a mechanical restriction of the superior oblique muscle tendon. Most commonly a congenital condition, acquired cases are usually caused by surgery, trauma or disorders associated with inflammation such as sinusitis, system lupus erythematosus or juvenile rheumatoid arthritis.(1,2) This is the first published case where Brown’s syndrome formed part of the clinical presentation of antibody negative hypothyroidism.