Recurrent hypokalemic paralysis: An atypical presentation of hypothyroidism

Abstract

Hypothyroidism presenting as recurrent hypokalemic paralysis is rare in the literature. This transient and episodic neurological condition is commonly associated with thyrotoxicosis. We report a case of young female admitted with recurrent paralytic attacks since last 1 year. She had no symptom of hypothyroidism. She had weakness of all four limbs, delayed relaxation of ankle jerks, and normal higher mental function. There was no enlargement of thyroid. Serum potassium level ranged from 1.6 to 3.2 meq/L during attack with high serum creatine phosphokinase level. Electromyography was normal. The patient was diagnosed having chronic thyroiditis with high thyroid-stimulating hormone and thyroid-related antibodies. Follow up shows satisfactory result with thyroxine replacement. It is an extremely rare and unusual presentation of hypothyroidism, probably the fourth reported case of hypothyroidism with hypokalemic paralysis, to the best of our knowledge.

Case Report: Recurrent hypokalemic periodic paralysis associated with distal renal tubular acidosis (type 1) and hypothyroidism secondary to Hashimoto's thyroiditis

“…Thyrotoxicosis is the most common secondary cause of HypoKPP; while hypothyroidism is an extremely rare cause of HypoKPP 6, 8 .…”

“…RTA is a rare cause of HypoKPP 6, 9– 12 . Table 5 in the paper by Rodríguez Soriano (2002) 15 summarizes the different characteristics of types of RTA, leading us to conclude that our patient had distal RTA (DRTA).…”

Sporadic hypothyroidism-related hypokalemic paralysis: Diagnosis in a resource-poor setting

“…HP with hypothyroidism has been reported on 15 occasions previously (16 adults, 2 children). [ 4 5 6 7 8 9 10 11 12 ] Eleven (11/18) patients with HP had hypokalemic periodic paralysis (HPP). One patient had resistance to thyroid hormone and was already on L-thyroxine without improvement in his episodic paralysis.…”

Case Report: Recurrent hypokalemic periodic paralysis associated with distal renal tubular acidosis (type 1) and hypothyroidism secondary to Hashimoto´s thyroiditis

“…In HypoKPP, whether by potassium movement into cells or by potassium loss, the resulting hypokalemia reduces the resting membrane potential and blocks the action potential 1,2 . The paralytic attacks occur suddenly with localized or generalized weakness, and can last from one hour to days 1,6 . Muscle provocation tests or genetic studies were performed in search of channelopathies.…”

“…Primary HypoKPP occurs when the channelopathies produce potassium intracellular translocation. Secondary HypoKPP is caused by the loss of potassium from kidneys, gastrointestinal tract or skin 1,[5][6][7][8][9] . HypoKPP cases related to thyroid disorders, more frequently thyrotoxicosis, and several autoimmune diseases have been previously reported 2,3,5 .…”