(14.13) A Case of Jod-Basedow phenomenon due to Sea Moss Gel Supplement use

Hyperthyroidism is an uncommon condition often associated with sympatho-adrenal symptoms. Grave’s disease is the most common cause and excess iodine intake; Jod-Basedow phenomenon (JBP) is a less common cause. We present a 54 yr old lady with hyperthyroid presentation induced by intake of the over-the-counter supplement, Sea Moss Gel (SMG).

Case(s) Description :

The patient is a 54 yr old postmenopausal lady referred for marked involuntary weight loss. She had no significant past medical history but had family history of hypothyroidism. She had anxiety, tremors, excess diaphoresis and heat intolerance but no palpitations or local neck symptoms. She had no ocular symptoms. She started taking SMG 2-3 times daily 3-4 mths prior to “improve her thyroid health”. Vitals were normal with BMI; 26kg/m2 and weight of 152lbs (51lb deficit from 3 mths ago). She had bilateral proptosis with no chemosis or conjunctival injection. She had bilateral lid retraction and diplopia on extreme upward gaze. She also had a goiter and 1.5cm left mid zone nodule with no neck adenopathy or bruits. Other than bilateral tremors of both hands the rest of the examination was normal. DEXA showed osteopenia and thyroid ultrasound showed multinodular goiter (MNG) with diffuse hypervascularity. Thyroid function tests; Free T4 2.25 ng/dl (0.71-1.51), Total T3 327ng/dl (80-180), TSH < 0.010 (0.4-4 uIU/ml), -ve thyroglobulin and thyroid peroxidase antibodies, serum thyroglobulin; 188 ng/ml (13-45), serum iodine 327ng/ml (40-82), 24 hr urine iodine; 2,600Ug/day (70-500), thyrotropin receptor antibody 3.2IU/ml (0-1.75) and thyroid stimulating immunoglobulin 3.58 (< 0.10 IU/ml). I-123 scan and uptake showed diffuse symmetric uptake; 6 hr uptake 8.5%(n) and 24 hr uptake 83.5% (elevated).  She was advised to stop all supplement use immediately and commenced on low dose methimazole. Her symptoms rapidly resolved and after ~ 3 mths she was near chemical euthyroidism (only suppressed TSH). She had subtotal thyroidectomy and is now on levothyroxine 112mcg daily with interval weight gain of ~ 30 lbs.

Discussion :

While the patient had long MNG and Grave’s disease this had been quiescent. Clinically symptoms were precipitated by intake of what she presumed to be an innocuous supplement to “improve” thyroid health. The result was the opposite and brought to fore previously dormant thyroid disease.

Caution is needed in the use of so called over-the-counter “thyroid supplements”. Some could be potentially dangerous. Iodine rich supplements like SMG can induce JBP in patients with or without prior thyroid disease. Such hyperthyroid presentations can lead to significant morbidity and potentially mortality if they induce thyroid storm.