Case report: Hyperthyroid hypokalemic periodic paralysis

• Published in: Annals of medicine and surgery Vol. 78; p. 103759
• Main Authors: Poudel Jaishi, Prakash, Neupane, Sandhya Kiran, Neupane, Prabhat Kiran
• Format: Journal Article
• Language: English
• Published: England Elsevier Ltd 01-06-2022; Elsevier
• Subjects: Beta blocker; Case Report; Case reports; Hyperthyroid hypokalemic periodic paralysis; Methimazole; Potassium supplementation; Beta blocker; Case reports; Methimazole; Hyperthyroid hypokalemic periodic paralysis; Potassium supplementation
• ISSN: 2049-0801; 2049-0801
• DOI: 10.1016/j.amsu.2022.103759

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.
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.
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.
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.
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.
•HHPP is a rare life-threatening complication of hyperthyroidism which is characterized by episodes of acute muscle weakness due to hypokalemia.•Periodic paralysis (PP) is a muscle disease, characterized by episodes of painless muscle weakness. These episodes can be triggered by strenuous exercise, fasting, or consuming high-carbohydrate foods.•Treatment cand be done by potassium supplementation until normalized serum potassium level. Patient must be kept in cardiac monitoring and serum potassium monitoring.•Hyperthyroidism can be treated with methimazole. Patient must be kept under regular follow up in endocrinology department.•Relapses can be prevented by treatment with radioactive iodine or surgery. Beta-blocking drugs have also been proven to reduce the frequency and severity of episodes.