Case report: Hyperthyroid hypokalemic periodic paralysis

INTRODUCTION AND IMPORTANCE: HHPP is a rare type of hypokalemic PP that can occur when there is hyperthyroidism.Thyrotoxic periodic paralysis is due to increased influx of potassium into skeletal muscle cells which leads to profound hypokalemia and paralysis. Insulin and Epinephrine are also responsible for stimulating the Na–K-ATPase pumps which are over expressed during hyperthyroid state. Laboratory hypokalemia in the background of hyperthyroidism with sudden symmetric paralysis point toward the diagnosis. CASE: We present a case of 25 year old male with limb weakness for 3hours following heavy dinner.He felt weakness after waking up in the morning where he could not move his both lower limbs. He also had difficulty moving upper limbs. CLINICAL FINDINGS AND INVESTIGATIONS: Examination revealed proximal muscle weakness with power of 2/5, decreased muscle tone, diminished deep tendon reflexes in all four limbs and equivocal plantar reflex bilaterally. Investigation sent were Total Leukocyte count, Hemoglobin, Renal function test, Liver Function test,Thyroid function test, Vitamin B12, Serology, ACTH, Serum calcium, Serum phosphate, Serum magnesium, Urine R/ME and Stool R/ME. INTERVENTION AND OUTCOME: Patient is treated with 10mEq/L/hr infusion of potassium chloride, methimazole and beta-blockers. He is stable and is in regular followup in medicine OPD. RELEVANCE AND IMPACT: Early diagnosis of HHPP is very essential to prevent fatal complications (cardiac and respiratory). It can be treated by timely potassium supplementation, methimazole and beta-blockers. Clinicians must be concerned about Hyperkalemia while supplementing Potassium in bed side.