Prevalence and risk factors of low vitamin D levels in children and adolescents with familial hypokalemic periodic paralysis.

Patients with familial hypokalemic periodic paralysis (HOKPP) experience episodes of reversible immobility and are at an increased risk of limited sunlight exposure, potentially leading to vitamin D deficiency. However, there is a lack of data on vitamin D levels in this population. We investigated serum vitamin D levels and their associated factors in children with HOKPP. This study included 170 genetically-confirmed children with HOKPP, aged 3-18 years, and 170 age-, sex-, and body mass index (BMI)-matched healthy controls from the Korean Channelopathy Study, a prospective controlled investigation. Anthropometric and clinical characteristics were recorded, and serum levels of calcium, ionized calcium, phosphorus, alkaline phosphatase, 25-hydroxyvitamin D, and intact parathyroid hormone (PTH) were analyzed. Vitamin D deficiency (< 20 ng/mL) was observed in 87.0% of the patients compared to 45.5% of the controls (P < 0.05) during the summer-fall season. During the winter-spring season, 91.7% of the patients and 73.4% of the controls were deficient (P < 0.05). A strong positive correlation was found between onset age of the first paralytic attack and vitamin D levels (r = 0.78, P < 0.01). Conversely, the frequency and duration of paralytic attacks were negatively correlated with vitamin D levels (r = -0.82 and r = -0.65, P < 0.01, respectively). Age, BMI, age at onset, frequency and duration of attacks, and PTH levels were independently associated with vitamin D levels (ß = -0.10, -0.12, 0.19, -0.27, -0.21, and -0.13, P < 0.05, respectively). CONCLUSIONS: Vitamin D deficiency was highly prevalent in children with HOKPP, and vitamin D levels correlated with various disease characteristics. We recommend routine screening for vitamin D levels in these patients to address this prevalent deficiency. Considering the high prevalence of vitamin D deficiency observed, further research on other diseases characterized by reversible immobility is warranted. WHAT IS KNOWN: • A correlation between immobility and low serum vitamin D levels has been established. However, the vitamin D status of patients with familial hypokalemic periodic paralysis (HOKPP) who experience periods of reversible immobility remains unknown. WHAT IS NEW: • Vitamin D deficiency was highly prevalent in children with HOKPP, and vitamin D levels correlated with various disease characteristics.

Thyrotoxic periodic paralysis presenting with quadriparesis and hyperreflexia.

Thyrotoxic periodic paralysis (TPP) is a rare complication of hyperthyroidism that manifests as painless flaccid paralysis. An East Asian man in his late 20s presented to the emergency department with an acute onset of quadriparesis associated with hypertonia and hyperreflexia. His initial symptoms and signs suggested involvement of the brain and spinal cord; however, MRI of the neuroaxis was normal. His serum potassium concentration was low, and thyroid test results were consistent with hyperthyroidism. The patient was diagnosed with TPP associated with Graves' disease and was treated with potassium supplementation, propranolol and methimazole. Motor strength improved to his baseline level of power; bulk was normal, and tone was increased. Although flaccid paralysis is a typical presentation of TPP, brisk reflexes and muscle spasticity cannot rule out this condition. This case highlights the importance of considering TPP as a possible diagnosis in patients presenting with acute quadriparesis.

Recurrent hypokalemic paralysis in hypothyroidism.

Hypothyroidism, a commonly encountered thyroid disorder, usually manifests with readily recognizable typical features. However, an unusual presentation of a classic thyroid disorder may hinder accurate diagnosis in certain instances. One such rare initial presentation of hypothyroidism is recurrent hypokalemic paralysis, and existing reports in the literature are sparse. It has been more commonly reported in thyrotoxicosis. We report the case details and clinical outcomes of two middle-aged individuals (a 34-year-old male and a 37-year-old female) with recurrent episodes of hypokalemic paralysis. Their clinical examination revealed pure motor hyporeflexia quadriparesis with hypotonia and diminished deep tendon reflexes without any autonomic dysfunction. They had no significant previous medical history. Biochemical findings revealed hypokalemia in both cases (1.4 and 1.9 mEq/L, respectively) with elevated levels of thyroid­stimulating hormone and thyroid­related antibodies in both individuals, thus, confirming the diagnosis of autoimmune hypothyroidism. Immediate treatment with intravenous and oral potassium correction helped in the recovery. Thyroxine supplementation was considered a follow-up treatment, and for a one-year follow-up period there were no complaints of limb weakness reported in both individual.

Arterial blood gas analysis aids early differential diagnosis and treatment of primary and secondary hypokalaemic periodic paralysis.

This study aimed to examine changes in electrolytes and acid-base status in primary and secondary hypokalaemic periodic paralysis (HypoPP), which will help early differential diagnosis of HypoPP. A total of 64 HypoPP patients were enrolled and relevant data from clinical records was collected. Overall, 64 patients (mean age 28.2±7.3 years) of which 58(91%) were males, with 39, 11 and 14 patients, respectively, diagnosed as primary HypoPP, thyrotoxic HypoPP, and other secondary HypoPPs at discharge, were assessed. Those with HypoPP secondary to conditions other than hyperthyroidism were more likely to develop acid-base imbalance (p<0.001); they had higher pH (p=0.046) and HCO3 levels (p=0.014) at baseline, and needed a higher dose of potassium supplement before the serum potassium level returned to normal (p=0.007) and a longer time to regain full muscle strength (p=0.004), compared with those with primary or thyrotoxic HypoPP. Emergent arterial blood gas analysis may aid early differential diagnosis of patients with primary and secondary HypoPP.

A dangerous food binge: a case report of hypokalemic periodic paralysis and review of current literature.

BACKGROUND: Hypokalemic periodic paralysis is a rare neuromuscular genetic disorder due to defect of ion channels and subsequent function impairment. It belongs to a periodic paralyses group including hyperkalemic periodic paralysis (HEKPP), hypokalemic periodic paralysis (HOKPP) and Andersen-Tawil syndrome (ATS). Clinical presentations are mostly characterized by episodes of flaccid generalized weakness with transient hypo- or hyperkalemia. CASE PRESENTATION: A teenage boy presented to Emergency Department (ED) for acute weakness and no story of neurological disease, during the anamnestic interview he revealed that he had a carbohydrates-rich meal the previous evening. Through a focused diagnostic work-up the most frequent and dangerous causes of paralysis were excluded, but low serum potassium concentration and positive family history for periodic paralyses raised the diagnostic suspicion of HOKPP. After the acute management in ED, he was admitted to Pediatric Department where a potassium integration was started and the patient was counselled about avoiding daily life triggers. He was discharged in few days. Unfortunately, he presented again because of a new paralytic attack due to a sugar-rich food binge the previous evening. Again, he was admitted and treated by potassium integration. This time he was strongly made aware of the risks he may face in case of poor adherence to therapy or behavioral rules. Currently, after 15 months, the boy is fine and no new flare-ups are reported. CONCLUSION: HOKPP is a rare disease but symptoms can have a remarkable impact on patients' quality of life and can interfere with employment and educational opportunities. The treatment aims to minimize the paralysis attacks by restoring normal potassium level in order to reduce muscle excitability but it seems clear that a strong education of the patient about identification and avoidance triggering factors is essential to guarantee a benign clinical course. In our work we discuss the typical clinical presentation of these patients focusing on the key points of the diagnosis and on the challenges of therapeutic management especially in adolescence. A brief discussion of the most recent knowledge regarding this clinical condition follows.

Stroke-mimicking unilateral hypokalemic paralysis and literature review.

Unilateral paralysis is an alarming symptom with broad differential diagnoses, including stroke, Todd's paralysis, myelopathy, and peripheral neuropathy. Hypokalemic paralysis (HP), a neuromuscular disorder associated with muscle dysfunction, is caused by hypokalemia and manifests as symmetric proximal extremity muscle weakness. Unilateral paralysis has rarely been reported in the literature. Once hypokalemia is corrected, HP is usually reversible. Delayed diagnosis and treatment may result in fatal consequences. Here, we report an atypical case of unilateral weakness along with a review of the literature on unilateral HP.

Refractory familial hypokalaemic periodic paralysis leading to cardiovascular compromise.

Familial hypokalaemic periodic paralysis (FHPP) is a rare neuromuscular disorder that is classified under periodic paralysis (PP), which is characterised by episodes of muscle weakness. Common triggers include intense exercise, fasting or consumption of carbohydrate-rich meals. Hypokalaemic PP has an incidence of 1 in 100 000; despite the temporal association, cardiac manifestations are exceedingly rare. We present a case of FHPP, a channelopathy presenting with severe refractory hypokalaemia. The challenges with our patient were maintaining potassium levels within normal ranges and initiating a close follow-up plan. Due to the lack of clinical guidance in our case, many aspects of care, including surveillance, medications and genetic testing, remain unaddressed. Medical management includes aggressive correction with supplements, potassium-sparing diuretics and carbonic anhydrase inhibitors. Severe cases of dysrhythmias, especially ventricular fibrillation, require electrophysiology evaluation and possible implantation of a defibrillator to prevent sudden cardiac death.

Thyrotoxic periodic paralysis in two sexagenarian men: A case report.

RATIONALE: Thyrotoxic periodic paralysis (TPP) characterized by the triad of muscle paralysis, acute hypokalemia, and the presence of hyperthyroidism is often reported in young adults but rarely reported in age >60 year-old. PATIENT CONCERNS: Two sexagenarian males (age 61 and 62) presenting to the emergency department with progressive muscle paralysis for hours. There was symmetrical flaccid paralysis with areflexia of lower extremities. Both of them did not have the obvious precipitating factors and take any drugs. DIAGNOSIS: Their Wayne scores, as an objective index of symptoms and signs associated with thyrotoxicosis, were <19 (7 and 14, respectively). Their blood pressure stood 162/78 and 170/82 mm Hg, respectively. Their thyroid glands were slightly enlarged. Both of them had severe hypokalemia (1.8 and 2.0 mmol/L). Their presumptive diagnosis of mineralocorticoid excess disorders with severe potassium (K+) deficit were made. However, low urine K+ excretion and relatively normal blood acid-base status were suggestive of an intracellular shift of K+ rather than K+ deficit. Hormone studies confirmed hyperthyroidism due to Graves disease. INTERVENTIONS: A smaller dose of K+ supplementation (only a total of 50 and 70 mmol K+, respectively) were prescribed for the patient. OUTCOMES: After treatment, their serum K+ levels became normal with a full recovery of muscle strength. LESSONS: Our 2 cases highlight the fact that thyrotoxic periodic paralysis must be still kept in mind as the underlying cause of hypokalemia with paralysis and hypertension in elderly patients to avoid missing curable disorders.

Hypokalaemic periodic paralysis secondary to subclinical hyperthyroidism: an uncommon cause of acute muscle paralysis.

Hypokalaemic periodic paralysis secondary to subclinical hyperthyroidism is an uncommon clinical phenomenon characterised by lower limb paralysis secondary to hypokalaemia in the background of subclinical hyperthyroidism. In this article, we report a patient who presented with progressive lower limb muscle weakness secondary to hypokalaemia that was refractory to potassium replacement therapy. He has no diarrhoea, no reduced appetite and was not taking any medication that can cause potassium wasting. Although he was clinically euthyroid, his thyroid function test revealed subclinical hyperthyroidism. His 24-hour urine potassium level was normal, which makes a rapid transcellular shift of potassium secondary to subclinical hyperthyroidism as the possible cause. He was successfully treated with potassium supplements, non-selective beta-blockers and anti-thyroid medication. This case report aimed to share an uncommon case of hypokalaemic periodic paralysis secondary to subclinical hyperthyroidism, which to our knowledge, only a few has been reported in the literature.

Parálisis periódica hipocaliémica: revisión sistemática de casos publicados / Hypokalemic periodic paralysis: a systematic review of published case reports

INTRODUCCIÓN: La parálisis periódica hipocaliémica es una enfermedad neuromuscular hereditaria que se caracteriza por presentar episodios de parálisis flácida o debilidad muscular relacionados con niveles bajos de potasio en sangre. Como consecuencia de su baja prevalencia, todavía hay aspectos clínicos y de manejo por caracterizar. PACIENTES Y MÉTODOS: Se desarrolla una revisión sistemática de los casos clínicos publicados en la última década, analizando las características demográficas y genéticas, las características de los episodios, los tratamientos recibidos y su respuesta, y las diferencias y evolución de los pacientes en función de las mutaciones de los genes más prevalentes: CACNA1S y SCN4A. RESULTADOS: Se incluyeron 33 artículos, que permitieron revisar a 40 sujetos. La edad media del inicio de los síntomas fue de 15,3 ± 9,7 años. El gen alterado con mayor frecuencia fue CACNA1S en 20 (60,5%) casos. Se observó que los sujetos con alteración del gen del canal de calcio CACNA1S presentaron niveles de potasio sérico inferiores, factores desencadenantes propios y una mayor proporción de sujetos con disnea en las crisis. La respuesta al tratamiento oral clásico con acetazolamida sólo alcanzó el 50%. Los diuréticos ahorradores de potasio y los fármacos antiepilépticos emergieron como una alternativa. CONCLUSIONES: La parálisis periódica hipocaliémica tiene una expresión clínica heterogénea con diferencias fenotípicas ligadas a las diferentes mutaciones genéticas. La respuesta al tratamiento preventivo habitual es subóptima. Son necesarios estudios prospectivos para poder discernir la mejor opción terapéutica en función de la carga genética

INTRODUCTION: Hypokalemic periodic paralysis is a neuromuscular disease characterized by a combination of flaccid paralysis episodes (or muscular weakness) that are related to low levels of potassium in blood. As a consequence of its low prevalence, there are still clinical and management aspects to characterize. PATIENTS AND METHODS: A systematic review of the clinical cases published in the last decade has been developed by analyzing demographic and genetic features, the episodes' characteristics, the received treatments, the response to them and also, the differences and evolution of patients depending on the most prevalent genetic alterations: CACNA1S and SCN4A. RESULTS: A total of 33 articles were included, allowing 40 individuals to be reviewed. The average age of onset of symptoms was 15.3 ± 9.7 years. The most frequent altered gene was CACNA1S in 20 (60.5%) cases. It was observed that subjects presenting an alteration of the gene responsible for the calcium channel, CACNA1S, presented lower serum potassium levels, own triggers and a higher proportion of subjects showing dyspnea during the crisis. Only 50% of the subjects respond to classical oral treatment with acetazolamide. Potassium-sparing diuretics and antiepileptics drugs emerge as an alternative. CONCLUSION: Hypokalemic periodic paralysis has an heterogeneous clinical expression with phenotypic differences linked to different genetic mutations. The common preventive treatment response is suboptimal. Prospective studies are needed to discern the best therapeutic option based on genetic load

Potassium losing, aldosterone producing adrenocortical carcinoma: a rare presentation.

Adrenocortical carcinomas (ACCs) are rare malignancies with an incidence of one to two per million per year. Aldosterone-producing ACCs (APACs) are extremely rare with an incidence less than 1%. We describe a rare case of APAC, presenting with episodic lower-limb weakness and hypertension. Our patient was found to have serum aldosterone levels of 20.8 ng/dL (2.5-15.2) with persistent hypokalaemia and a 9.7×8.3×7.7 cm right adrenal mass, which was suspicious of malignancy on evaluation. He underwent a complete surgical resection which confirmed the diagnosis of ACC and normalised his aldosterone and potassium levels. He was then subjected to postoperative chemotherapy. Postoperative adjuvant chemotherapy with mitotane has a role in preventing recurrence.

[Thyrotoxic hypokalemic periodic paralysis in two African black women]. / Paralysie périodique hypokaliémique thyrotoxique chez deux femmes noires africaines.

Thyrotoxic hypokalemic periodic paralysis is a rare complication of hyperthyroidism. It has been most often reported in Asian subjects while it has been little described in the black population. Its mechanism has been little elucidated, but it would be caused by hyperactivity of the Na+/K+pump. We here report two cases of thyrotoxic hypokalemic periodic paralysis in black African subjects. The clinical manifestation was identical in both patients: proximal muscle paralysis of the lower limbs. Paralysis was associated with severe hypokalemia and occurred in female patients treated for Graves' disease without any other associated disease. Outcome was immediately favorable under potassium supplementation. Treatment of hyperthyroidism prevented recurrences. This study highlights the importance of suspecting the diagnosis of thyrotoxic hypokalemic periodic paralysis despite its rarity in the black African population.