Hypokalemic Periodic Paralysis Precipitated by Thyrotoxicosis and Renal Tubular Acidosis

Abstract

Background. Hypokalemic periodic paralysis is a rare neuromuscular disorder characterized by transient episodes of flaccid paralysis due to a defect in muscle ion channels. Most cases are hereditary, but it can be acquired. We present a case of acquired hypokalemic periodic paralysis associated with hyperthyroidism and renal tubular acidosis. Clinical Case. A 38-year-old female with a history of Graves’ disease presented to the emergency department with generalized weakness and associated nausea, vomiting, and weight loss. Examination was significant for diffuse weakness in all extremities. Labs showed hypokalemia, hyperthyroidism, and nonanion gap metabolic acidosis with a positive urine anion gap. She was treated for hypokalemic periodic paralysis and renal tubular acidosis. Potassium replacement, propranolol, methimazole, and sodium bicarbonate were initiated. Her potassium gradually corrected with resolution of her symptoms. Further investigation revealed a history of dry eyes, dry mouth, and recurrent dental carries. She had positive ANA, SS-A, and SS-B antibodies. She was diagnosed with Sjögren’s syndrome, which may have been associated with her Graves’ disease and thus contributed to both her RTA and hyperthyroidism. Conclusion. Early recognition and treatment of thyrotoxic periodic paralysis are important to prevent cardiac complications. Management includes potassium replacement with careful monitoring to prevent rebound hyperkalemia. The definitive treatment is to achieve euthyroid status.

The Aging Features of Thyrotoxicosis Mice: Malnutrition, Immunosenescence and Lipotoxicity

“…Mice deficient in carbonic anhydrase 2 (Car2−/− mice) have metabolic acidosis, impaired urine acidification, and are deficient in normal intercalated cells ( 71 ). The present study showed that the abundance of Ca1 and Ca2 in thyrotoxicosis mice were both downregulated, which might be the reason for hyperthyroidism associated renal tubular acidosis ( 72 ). A study showed that the expression of the Ca2 gene in zebrafish decreased with age, and Ca2 can be used as a biomarker of aging ( 73 ).…”

Thyrotoxic Hypokalemic Periodic Paralysis: A Case Report

“…4 In the absence of a family history of paralysis, renal tubular acidosis should also be considered. 5 Symptoms of hyperthyroidism may not always be evident in patients, or muscle paralysis could be the first manifestation of thyrotoxicosis. THPP can be complicated with ventricular fibrillation or hypercapnic respiratory failure if not diagnosed and treated promptly.…”

Distal Renal Tubular Acidosis in Patients with Autoimmune Diseases—An Update on Pathogenesis, Clinical Presentation and Therapeutic Strategies

“…Two additional case reports with this association were published in 2020, and another study published recently showed a prevalence of 14.81% of DRTA (16 patients) in a cohort of 108 patients with SLE [ 6 , 7 , 8 ]. Generally, the majority of cases with complete DRTA published in literature are diagnosed due to severe symptoms associated with hypokalemia, such as quadriparesis or even respiratory arrest, and therefore, the real prevalence of DRTA associated with autoimmune diseases is difficult to estimate [ 6 , 9 , 10 , 11 , 12 , 13 , 14 , 15 , 16 , 17 , 18 , 19 , 20 , 21 , 22 ]. Therefore, urinary acidification tests are essential in diagnosing those patients who did not develop any symptoms and would otherwise escape undiagnosed.…”

“…Aiming for a better understanding of the disease, we performed a search of the PubMed database using MeSH descriptors (Acidosis, Renal Tubular; Lupus Erythematosus, Systemic; Sjogren’s Syndrome, Systemic Vasculitis, Rheumatoid Vasculitis, Arthritis, Rheumatoid, Anti-Neutrophil Cytoplasmic Antibody-Associated Vasculitis, Churg-Strauss Syndrome, IgA Vasculitis, Spondylitis, Ankylosing, Cryoglobulins, Hepatitis, Autoimmune, Liver Cirrhosis, Biliary), and we identified 37 individual case reports published since December 2016 with the association of distal renal tubular acidosis and the following autoimmune disorders: SLE, Sjögren’s syndrome, autoimmune hepatitis, primary biliary cirrhosis and rheumatoid arthritis (see Table 1 ) [ 6 , 10 , 11 , 13 , 15 , 16 , 17 , 18 , 20 , 24 , 25 , 26 , 27 , 28 , 29 , 30 , 31 , 32 , 33 , 34 , 35 , 36 , 37 , 38 ]. We also identified a case of hereditary autoimmune polyendocrine syndrome (DRTA, hypoparathyroidism, Addison disease), published in a series of cases, which was not included in our analysis, due to the lack of individual data availability [ 39 ].…”

“…In all of these cases, it is mentioned that acidosis and hypokalemia were not ameliorated and the patients remained dependent on oral supplementation with potassium and bicarbonate. However, there are also some examples in which immunosuppressive therapy seems to improve distal tubular function because, after a period of treatment, oral supplementation for potassium and alkali was no longer needed [ 11 , 28 , 32 ]. One of the patients received only hydroxychloroquine, another patient received a combination of hydroxychloroquine and prednisone and the last patient received rituximab.…”