MASSIVE PERICARDIAL EFFUSION AS A PRIMARY MANIFESTATION OF HYPOTHYROIDISM

Abstract

INTRODUCTION/BACKGROUND
Hypothyroidism is an endocrine disorder with multiorgan involvement and various complications. Mild pericardial effusion is a common cardiovascular complication but massive pericardial effusion with cardiac tamponade as initial presentation of hypothyroidism is rare.

CASE
We report a 70-year-old female with a history of hyperthyroidism who was treated with radioiodine ablation more than 20 years ago. She defaulted followup and hence was not on L-thyroxine. She presented with progressive exertional dyspnoea and hypothyroid symptoms (weight gain, fatigue, cold intolerance) for a month. On examination, she had coarse dry skin, periorbital oedema, and bradycardia. She was normotensive. Her heart sounds were not muffled. Biochemically she was in overt hypothyroidism, TSH 16.825 m IU/L (0.35-4.94), T4 <5.41 pmol/L (9.01-19.05). She also had hyponatremia with a sodium level of 118-125 mmol/L and hyperlipidaemia. She had cardiomegaly on a chest x-ray. Her electrocardiogram showed normal voltage complexes with no electrical alternans. Her echocardiography showed massive pericardial effusion (3.1 cm) with a collapsible right atrium. She had normal ventricular function. Pericardiocentesis was performed and 150 cc straw-coloured fluid was aspirated. The pericardial fluid was exudative. Cultures were negative for bacteria and acid-fast bacilli. There were no malignant cells. She was treated with L-thyroxine 75 mcg daily. TFTs repeated six weeks later were already normal with TSH of 2.521 m IU/L (0.35-4.94) and T4 of 12.76 pmol/L (9.01- 19.05). Repeat echocardiography showed resolution of the pericardial effusion. Clinically, she remained asymptomatic.

CONCLUSION
Although massive pericardial effusion is an uncommon initial presentation of hypothyroidism, it can occur in longstanding untreated cases. Pericardial effusion can resolve with adequate thyroid hormone replacement therapy.