Thyroid storm is a rare complication of thyrotoxicosis, life-threatening if not managed appropriately.
We report a 43-year-old woman who presented to emergency services with shortness of breath, palpitations and weight loss. She was pale, cachectic, in atrial fibrillation and had signs of decompensated heart failure. Investigations showed: WBCs: 3.2×109/l, neutrophils 2.1×109/l, Hb 53 g/l, platelet 233, TSH <0.02 mIU/l, FT4 64 (1025 pmol/l), FT3 19 (2.87 pmol/l) and Thyroid stimulating antibody >40 U/l confirming a diagnosis of Graves disease. Chest X-ray showed bilateral pleural effusions, ECG confirmed atrial fibrillation with rate of 130/min. Echocardiogram demonstrated moderate LVSD with mild mitral and tricuspid regurgitations.
Due to initial suspicion of wet beri-beri, she was treated with diuretics, blood transfusion, thiamine then commenced on Digoxin & betablocker for rate control.
Following endocrinology review, carbimazole 30 mg once daily was commenced. On day 3, she became hypotensive, WBC dropped to 2.7 and neutrophils to 1.7. Carbimazole was switched to Propylthiouracil due to agranulocytosis. At that point FT4 was 30 pmol/l. Patient declined OGD hence was not anti-coagulated due to undiagnosed iron deficiency anaemia pending outpatient CT angiogram.
1. Thyroid storm diagnosis needs high index of suspicion since symptoms may resemble any high cardiac output state e.g. severe sepsis or anaemia and it might be precipitated by them.
2. Both thyroid storm and sepsis can cause leucopoenia, however, vigilance and observation for rare complications of antithyroid drugs including agranulocytosis needs to be considered.
3. There is a solid evidence to suggest that patients with untreated overt thyroid dysfunction are at increased risk of cardiac dysfunction. Persistent sub-clinical thyroid dysfunction is associated with the development of Heart failure.
4. Pernicious anaemia is commonly reported with hyperthyroidism, although there are some reports of microcytic anaemia; however its severity in this case suggests a coexisting aetiology.