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.

A novel CACNA1S gene variant in a child with hypokalemic periodic paralysis: a case report and literature review

BACKGROUND

The CACNA1S gene encodes the alpha 1 S-subunit of the voltage-gated calcium channel, which is primarily expressed in the skeletal muscle cells. Pathogenic variants of CACNA1S can cause hypokalemic periodic paralysis (HypoPP), malignant hyperthermia susceptibility, and congenital myopathy. We aimed to study the clinical and molecular features of a male child with a CACNA1S variant and depict the molecular sub-regional characteristics of different phenotypes associated with CACNA1S variants.

CASE PRESENTATION

We presented a case of HypoPP with recurrent muscle weakness and hypokalemia. Genetic analyses of the family members revealed that the proband had a novel c.497 C > A (p.Ala166Asp) variant of CACNA1S, which was inherited from his father. The diagnosis of HypoPP was established in the proband as he met the consensus diagnostic criteria. The patient and his parents were informed to avoid the classical triggers of HypoPP. The attacks of the patient are prevented by lifestyle changes and nutritional counseling. We also showed the molecular sub-regional location of the variants of CACNA1S which was associated with different phenotypes.

CONCLUSIONS

Our results identified a new variant of CACNA1S and expanded the spectrum of variants associated with HypoPP. Early genetic diagnosis can help avoid diagnostic delays, perform genetic counseling, provide proper treatment, and reduce morbidity and mortality.

Sinus arrest in familial hypokalemic periodic paralysis caused by SCN4A mutation: a case report

BACKGROUND

Primary hypokalemic periodic paralysis (HypoPP), a rare skeletal muscle channelopathy resulting in episodic muscle weakness or paralysis under hypokalemic conditions, is caused by autosomal-dominant genetic mutations. HypoPP limits physical activity, and cardiac arrhythmias during paralytic attacks have been reported. We describe a rare familial HypoPP case complicated by sinus arrest and syncope requiring urgent temporary pacemaker implantation.

CASE REPORT

A 27-year-old Vietnamese man with a family history of periodic paralysis presented with his third attack of muscle weakness triggered by intense football training the previous day. Clinical and laboratory features justified a HypoPP diagnosis. During intravenous potassium replacement, the patient experienced syncopal sinus arrest requiring urgent temporary pacemaker implantation. The patient gradually improved, responding favorably to oral potassium supplements. Genetic testing revealed an Arg1132Gln mutation in the sodium ion channel (SCN4A, chromosome 17: 63947091). At discharge, the patient received expert consultation regarding nonpharmacological preventive strategies, including avoidance of vigorous exercise and carbohydrate-rich diet.

CONCLUSIONS

No evidence has established a relationship between hypokalemia and sinus arrest, and no specific treatment exists for familial HypoPP due to SCN4A mutation. Clinician awareness of this rare condition will promote appropriate diagnostic approaches and management strategies for acute paralytic attacks. Treatment should be tailored according to HypoPP phenotypes and genotypes.

[Muscle weakness in the extremities in a man with Graves' disease]

A 42-year-old man of Chinese descent, known to have Graves' disease, presented with muscle weakness. Neurological examination showed paralysis of the arms and legs, with intact sensory function, while blood-test revealed hypokalaemia and thyrotoxicosis. The neurological symptoms resolved quickly after correction of the serum potassium level. Thyrotoxic periodic paralysis is a rare, reversible complication of hyperthyroidism is characterised by hypokalaemia, hyperthyroidism and paralysis.

The long exercise test as a functional marker of periodic paralysis

AIMS

The aim of this study was to evaluate the sensitivity of the long exercise test (LET) in the diagnosis of periodic paralysis (PP) and assess correlations with clinical phenotypes and genotypes.

METHODS

From an unselected cohort of 335 patients who had an LET we analyzed 67 patients with genetic confirmation of PP and/or a positive LET.

RESULTS

32/45 patients with genetically confirmed PP had a significant decrement after exercise (sensitivity of 71%). Performing the short exercise test before the LET in the same hand confounded results in four patients. Sensitivity was highest in patients with frequent (daily or weekly) attacks (8/8, 100%), intermediate with up to monthly attacks (15/21, 71%) and lowest in those with rare attacks (9/16, 56%) (p = .035, Mann-Whitney U-test). Patients with a positive LET without confirmed PP mutation comprised those with typical PP phenotype and a group with atypical features.

DISCUSSION

In our cohort, the LET is strongly correlated with the frequency of paralytic attacks suggesting a role as a functional marker. A negative test in the context of frequent attacks makes a diagnosis of PP unlikely but it does not rule out the condition in less severely affected patients.

Thyrotoxic periodic paralysis (TPP): assessment in the emergency department

A male patient aged in his early twenties presented to the emergency department (ED) with quadriparesis. He was ordinarily fit and well and had exercised and eaten a carbohydrate rich meal the evening before. His point-of-care venous blood sample on arrival to the ED showed hypokalaemia of 1.6 mmol/L. (normal range=3.5-5.0 mmol/L). He was put on a cardiac monitor and started on an intravenous infusion of potassium chloride. With the benefit of hindsight, his male sex, particular features in his history and his initial ECG all pointed to a differential diagnosis of thyrotoxic periodic paralysis (TPP), although a differential diagnosis of a first attack of familial hypokalaemic paralysis was considered. As urgent thyroid function tests were sent promptly, there was minimal delay in reaching a diagnosis of TPP and promptly starting propranolol as a safe and more effective means of reversing TPP, followed by definitive treatment with carbimazole.

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.

Novel CACNA1S mutation in hypokalaemic periodic paralysis

A 15-year-old girl was admitted to emergency department with an acute flaccid tetraparesis with no other symptoms. A history of recurrent similar episodes with spontaneous recovery was reported and no family history was known. Laboratory tests revealed severe hypokalaemia and hypokaluria. Symptoms resolution occurred after potassium replacement. The diagnosis of hypokalaemic periodic paralysis (HPP) was confirmed by genetic testing, which revealed a not previously described mutation in CACNA1S gene (c.3715C>G p.Arg1239Gly). HPP is a rare neuromuscular disorder that causes episodic attacks of flaccid paralysis with concomitant hypokalaemia. Primary forms of the disease are skeletal muscle ion channelopathies. HPP occurs due to a problem in potassium distribution rather than a total body potassium deficiency. Therefore potassium replacement should be carefully performed because of the risk of rebound hyperkalaemia. Knowing this rare entity is important in order to avoid diagnostic delays and so that proper treatment can be initiated to reduce morbidity and mortality.

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.

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.

Skeletal Muscle Channelopathies

Skeletal muscle channelopathies are rare genetic neuromuscular conditions that include the nondystrophic myotonias and periodic paralyses. They cause disabling muscle symptoms and can limit educational potential, work opportunities, socialization, and quality of life. Effective therapy is available, making it essential to recognize and treat this group of disorders. Here, the authors highlight important aspects regarding diagnosis and management using illustrative case reports.

[Thyrotoxic hypokalemic periodic paralysis in two African black women]

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.

33-year-old man • flaccid paralysis in limbs • 30-lb weight loss • thyromegaly without nodules • Dx?

Flaccid paralysis in arms and legs. 30-lb weight loss in previous month. Thyromegaly without nodules. Dx?

[Hypokalemic Paresis in Adolescent: A Case Report]

Familial hypokalaemic periodic paralysis is a rare autosomal dominant neuromuscular disease characterized by episodic attacks of flaccid paralysis with concomitant hypokalaemia. We present a case of a 15-year-old male adolescent observed in the pediatric emergency department by flaccid paresis of the 4 limbs of sudden onset and progressive worsening. In the anamnesis, corticosteroid and antihistamine intake were observed on the previous day for urticaria and family history of transient episodes of flaccid paralysis in adolescence, asymptomatic after the fourth decade of life, without an established diagnosis. Diagnostic tests revealed hypokalaemia (K + < 2.4 mEq/L), without hypokaluria and without other changes. Symptomatology resolution after supplementation with potassium was verified until normalization of kaliemia. Flaccid paralysis is a rare form of presentation of hypokalaemia. Several etiologies may be involved in the child or adolescent presenting with acute flaccid paralysis. The description of this case draws attention to the importance of the knowledge of this entity, because if recognized and treated properly, patients usually recover without sequelae.

Thyrotoxic periodic paralysis with ventricular tachycardia

A 47-year-old man presented to our emergency department (ED) with limbs weakness for 2 h. His heart rate was 127 beats per minute and blood pressure was 95/49 mm Hg. He found weakness of limbs after 4-h sleep. Physical examinations revealed that the muscle strength of upper limbs is 3/5, and lower limbs are 2/5. Electrocardiogram (ECG) revealed wide QRS complex, monomorphic ventricular tachycardia (VT) with ST-segment depression and long QT interval. Serum potassium level was extremely low as 1.0 mEq/L. This led to periodic hypokalemic paralysis. Due to severe hypokalemia with possible atrioventricular block, the patient was admitted to the intensive care unit. During hospitalization, his potassium level returned to 5.1 mEq/L on the first day. He had a low level of thyroid stimulating hormone (TSH) of <0.03 micro-IU/mL (normal range: 0.25-4.00) and a high free thyroxine (T4) level of 2.43 ng/dL (normal range: 0.89-1.79 ng/dL). Therefore, hyperthyroidism was diagnosed, and 5 mg of methimazole was administered twice a day. The patient was discharged on the seventh day after admission. The final diagnosis is thyrotoxic periodic paralysis (TPP), also as known as nocturnal paralysis or night palsy.

Thyrotoxic Channelopathies

Thyrotoxic periodic paralysis (TPP), a disorder most commonly seen in Asian men, is characterized by abrupt onset of hypokalemia and paralysis. The condition primarily affects the lower extremities and is secondary to thyrotoxicosis. Early recognition of TPP is vital to initiating appropriate treatment and to avoiding the risk of rebound hyperkalemia that may occur if high-dose potassium replacement is given. Here we present a case of 31 year old male with thyrotoxic periodic paralysis with diagnostic and therapeutic approach.

Thyrotoxicosis presenting as hypokalaemic paralysis and hyperlactataemia in an oriental man

A 35-year-old Malaysian man presented with rapid onset of flaccid quadriparesis associated with nausea and vomiting. General blood tests revealed severe hypokalaemia (serum potassium 1.5 mmol/L) and hypophosphataemia (serum phosphate 0.29 mmol/L) as a potential cause of the flaccid paralysis. Arterial blood gases showed mixed acid base disturbance of respiratory alkalosis and metabolic acidosis with hyperlactataemia. Thyrotoxic periodic paralysis (TPP) was suspected as the underlying cause of this presentation and thyroid function tests showed severe hyperthyroid results (free T4 > 77.2 pmol/L, free T3 19.3 pmol/L, thyroid-stimulating hormone [TSH] < 0.05 mIU/L). Treatment with intravenous potassium and phosphate infusion and oral propranolol resulted in rapid resolution of his symptoms. A discussion of the clinical and pathophysiological features and treatment of TPP (a very rare encounter in UK clinical practice) is presented, and to our knowledge associated hyperlactataemia has not been previously described.

Clinical and Aetiological Spectrum of Hypokalemic Flaccid Paralysis in Western Odisha

OBJECTIVE

To study the clinical profile of hypokalemic flaccid paralysis (HKFP) and to evaluate its causes.

METHODS

Fifty cases of hypokalemic flaccid paralysis (HKFP) admitted between November 2012 to October 2014 were taken up in the study. Serum potassium level < 3.5 mmol/ltr has been taken as hypokalemia. All cases were studied for spot and/or 24 hour urinary sodium / potassium, serum potassium / calcium / magnesium. Hypokalemic periodic paralysis (HPP) were diagnosed if there was spot/24 hour urine potassium excretion < 20mmol/ltr in presence of hypokalemia and flaccid weakness without other causes. EMG and nerve conduction study were done to exclude polyneuropathy and myopathic cases.

RESULTS

Out of 50 cases of HKFP, male gender predominated (88%). Maximum number of cases (70%) occurred in 21 to 40 years of age. It occurred in all seasons but more in summer (58%). The precipitating factors were present in 76% of cases out of which high carbohydrate meal (28%), vomiting (16%), excessive sweating (8%), diarrhea (8%) and increased urination (12%) were present. Twenty percent of cases had recurrence (2 to 3 episodes most often) and 6% of cases had family history. Quadriparesis was seen in (54%), paraparesis (36%), hemiparesis (10%) and neck muscle weakness (32%). No case was present with respiratory paralysis or cranial nerve palsy. Twenty-one cases (42%) have very low potassium < 2.5 mmol/ltr, 11 cases (22%) with potassium level between 2.5 to 2.9 mmol/ltr and 18 cases (36%) with 3 to 3.5 mmol/ltr. There was no correlation between severity weakness and potassium level. Eleven cases (22%) had thyrotoxicosis and 3 cases (6%) were hypothyroid. Thirteen cases (26%) have excess urinary loss of potassium (≥20 mmol/ltr) of which 5 cases (10%) were distal renal tubular acidosis (dRTA), four cases (8%) were Gitelman's syndrome (GS) and in 4 cases exact cause could not be diagnosed. Non-renal / prior renal loss of potassium like diarrhea and excessive sweating was responsible in 8% cases each and vomiting in 10% of cases. One unique case of hypernatraemic hypokalemic paralysis (HHP) was found. Only 9 (18%) cases are hypokalemic periodic paralysis (HPP).

CONCLUSIONS

HKFP is a hetergenous group of disease of which a significant number of patients had thyroid disorders mostly in the form of thyrotoxicosis followed by renal tubular dysfunctions like dRTA and GS; non-renal and prior renal loss of potassium like diarrhea, excessive sweating and vomiting respectively. Early recognition and prompt management of these conditions will give gratifying result and prevent further attacks in some cases.

An Unusual Case of Acute Muscle Weakness

A previously healthy 35-year old man presented to hospital with acute leg weakness following an alcohol binge. On assessment, tachycardia, urinary retention and bilateral upper and lower limb proximal weakness with preserved peripheral power were noted. Biochemistry revealed marked hypokalaemia, which responded to intravenous replacement, and biochemical thyrotoxicosis, leading to the diagnosis of Thyrotoxic Periodic Paralysis (TPP). Anti-thyroid therapy and beta-blockers were commenced and his neurological symptomatology resolved as he became progressively euthyroid. TPP is a rare acquired subtype of hypokalaemic periodic paralysis, typically causing proximal muscle weakness associated with thyrotoxicosis. It is most common in young Asian males. Acute treatment requires cautious oral potassium supplementation, beta-blockade, and anti-thyroid therapy. TPP is prevented by maintaining euthyroidism; otherwise recurrence is likely.

Hypokalemic Paralysis Complicated by Concurrent Hyperthyroidism and Chronic Alcoholism: A Case Report

Thyrotoxic periodic paralysis (TPP) is characterized by the presence of muscle paralysis, hypokalemia, and hyperthyroidism. We report the case of a young man with paralysis of the lower extremities, severe hypokalemia, and concurrent hyperthyroidism. TPP was suspected; therefore, treatment consisting of judicious potassium (K+) repletion and β-blocker administration was initiated. However, urinary K+ excretion rate, as well as refractoriness to treatment, was inconsistent with TPP. Chronic alcoholism was considered as an alternative cause of hypokalemia, and serum K+ was restored through vigorous K repletion and the addition of K+ -sparing diuretics. The presence of thyrotoxicosis and hypokalemia does not always indicate a diagnosis of TPP. Exclusion of TPP can be accomplished by immediate evaluation of urinary K+ excretion, acid-base status, and the amount of potassium chloride required to correct hypokalemia at presentation.

Thyrotoxic, hypokalemic periodic paralysis (THPP) in adolescents

INTRODUCTION

Periodic paralysis associated with hyperthyroidism and hypokalemia is an uncommon disorder reported primarily in Asian males and rarely in children. We report three Hispanic adolescent males who were seen with Graves' disease (GD) and THPP.

METHODS

The method used was chart review.

RESULTS

Two of these boys presented with episodes of paralysis and were diagnosed with GD. The third was initially seen with hyperthyroidism and developed weakness and paralysis when his disease progressed because of therapeutic noncompliance. Hypokalemia was documented in two of the three patients with the third not seen during paralysis. Intravenous K⁺ was required in only one case. All three boys were treated with antithyroid medications and β blockers, and the musculoskeletal symptoms resolved in all three when hyperthyroidism was controlled after 2 weeks of treatment. The duration for each episode of weakness and paralysis varied in each case and resolved within 15 min to 2 h in case 1, 1-5 h in case 2, and 24 h in case 3.

CONCLUSIONS

THPP is considered uncommon except in Asian males and rare in childhood and adolescence. Its occurrence in these three Hispanic boys suggests that it may occur more frequently in the young and in the USA than has been suspected, especially with the changing national demographics. We believe that our experience should raise the awareness of THPP among pediatric care providers.

Hyperthyroidism · myalgia · rapidly progressing paralysis · Dx?

A 26-year-old Hispanic woman presented to the emergency department (ED) with myalgia and weakness. There were no prior symptoms and family history was negative for endocrinopathies. She was admitted and started on methimazole 10 mg twice a day for thyroid suppression and given propranolol 10 mg twice a day for anticipated hyperadrenergic adverse effects. The remainder of her hospital stay was uneventful and she was discharged 6 days after admission. Soon after, an outpatient thyroid scan ordered by her primary care physician confirmed that the patient had Graves' disease.

[Hereditary hypokaliaemic periodic paralysis in a 13-year-old boy]

Hypokaliaemic periodic paralysis is a rare hereditary neuro-muscular disease caused by an error in the ion-canals in muscle cells resulting in decreased excitabiliy. It presents itself in the late childhood or teenage years with a periodic paralysis without involving respiratory and heart muscles. Our patient was a 13-year-old boy, who woke up with decreased strength in arms and legs after excessive physical activity and a high carbo-hydrate intake. Tests showed a low P-potassium level. The patient had full remission of his symptoms within 24 hours.

[Thyrotoxic hypokalemic periodic paralysis in patients of African descent]

Thyrotoxic hypokalemic periodic paralysis (THPP) is an endocrine emergency marked by recurrent attacks of muscle weakness associated with hypokalemia and thyrotoxicosis. Asiatic male patients are most often affected. On the other hand, African descents rarely present this disease. The case described shows an afrodescendant patient with hypokalemia and tetraparesis, whose diagnosis of hyperthyroidism was considered during this crisis. The THPP, although rare, is potentially lethal. Therefore, in cases of flaccid paresis crisis this diagnosis should always be considered, especially if associated with hypokalemia. In this situation, if no previous diagnosis of hyperthyroidism, this should also be regarded.

[A case of thyreotoxic hypokalaemic periodic paralysis in a white male]

BACKGROUND

Thyreotoxic hypokalaemic periodic paralysis (THPP) is a rare and potentially life-threatening syndrome. It principally affects men of East-Asian origin and has rarely been described in a white person.

CASE DESCRIPTION

A 34-year-old Dutch man, suffering from Graves' disease, presented with weakness in his lower limbs. Laboratory investigation showed severe hypokalaemia (1.8 mmol/l) and increased creatinine kinase levels. An electrocardiogram showed atrial fibrillation with a prolonged QTc-interval. The patient was admitted, cardiac rhythm was monitored, and he received potassium supplements. Laboratory investigation of thyroid function showed thyrotoxicosis. The patient was treated with propranolol and thiamazol. At follow-up, thyroid function, potassium levels and muscle strength had normalized.

CONCLUSION

Hypokalaemia due to thyrotoxicosis should be considered in cases of unexplained paralysis. The treatment of THPP consists of treating for hyperthyroidism plus propranolol. Since the hypokalaemia is self-limiting, potassium supplementation is only necessary in cases of rhythm disturbances or cardiac-conduction disturbances. Despite adequate treatment, there is a risk of recurrence. Regular monitoring is indicated until euthyroidism is achieved.

Thyrotoxic hypokalemic periodic paralysis: two case reports and a brief review of literature

Thyrotoxic Hypokalemic Periodic Paralysis (THPP) is a rare complication of thyrotoxicosis and can sometimes be fatal. It needs early recognition for proper management and prevention of recurrences. Here we describe two cases presenting with acute onset of paresis, low potassium levels, low levels of thyroid-stimulating hormones (TSH), and elevated thyroid hormone levels.

Thyrotoxic periodic paralysis with Graves' disease leading to the discovery of a hidden nonclassic 11β hydroxylase deficiency

11β hydroxylase deficiency (OHD) is one of the main causes of congenital adrenal hyperplasia. There have been only a few reported cases of nonclassic 11β OHD, a milder form of the disease. It is difficult to detect occult nonclassic 11β OHD because patients present with no or mild symptoms. We herein present a case of thyrotoxic periodic paralysis (TPP) with Graves' disease leading to the discovery of a hidden nonclassic 11β OHD. In this case, increased levels of thyroid hormone seem to have induced symptoms of occult nonclassic 11β OHD and aggravated TPP.

Hypokalemic periodic paralysis, facial dysmorphism and ventricular arrhythmia (clinical triad of Andersen-Tawil syndrome)

Andersen-Tawil Syndrome (ATS) is a rare potassium channel disorder, characterized by episodic weakness, ventricular arrhythmias and dysmorphic features (short stature, scoliosis, clinodactyly, hypertelorism, small or prominent low set ears, micrognathia and broad forehead). We report a case of hypokalemic periodic paralysis with dysmorphic facial features and ventricular arrhythmia resembling Andersen-Tawil syndrome.

Gitelman's syndrome presenting with hypocalcaemia, basal ganglia calcification and periodic paralysis

Gitelman's syndrome (GS), also referred to as familial hypokalaemia-hypomagnesaemia syndrome, is an autosomal recessive renal tubular disorder characterised by hypokalaemic metabolic alkalosis, hypomagnesaemia and hypocalciuria. It is caused by a defect of the thiazide-sensitive sodium chloride co-transporter at the distal tubule. This condition was previously confused with Bartter syndrome. Documentation of hypocalciuria helps to differentiate GS from Bartter syndrome. We report a 44-year-old woman who presented with a history of seizure disorder and periodic paralysis. On investigation, she was found to have hypokalaemic metabolic alkalosis, hypomagnesaemia, hypocalciuria, hypoparathyroidism, hypocalcaemia and basal ganglia calcification, consistent with GS. The atypical features in our case, namely basal ganglia calcification and hypocalcaemia, prompted the writing of this case report.

A young man presenting with paralysis after vigorous exercise

Thyrotoxic periodic paralysis (TPP) is a rare metabolic disorder characterised by muscular weakness and paralysis in predisposed thyrotoxic patients. Although patients with TPP are almost uniformly men of Asian descent, cases have been reported in Caucasian and other ethnic populations. The rapid increase in ethnic diversity in Western and European nations has led to increase in TPP reports, where it was once considered exceedingly rare. Correcting the hypokalaemic and hyperthyroid state tends to reverse the paralysis. However, failure to recognise the condition may lead to delay in diagnosis and serious consequences including respiratory failure and death. We describe a young man who was diagnosed with hyperthyroidism who presented with acute paralysis. The clinical characteristics, pathophysiology and management of TTP are reviewed.

Sjogren's syndrome presenting with hypokalemic periodic paralysis

We report a rare case of a 38-year-old female who presented with sudden onset flaccid quadriplegia and respiratory arrest with no significant past clinical history. She was later found to have hypokalemia due to distal renal tubular acidosis and further diagnosed as case of Sjogrens Syndrome.

Thyrotoxic periodic paralysis associated with transient thyrotoxicosis due to painless thyroiditis

Thyrotoxic periodic paralysis (TPP) is a rare manifestation of hyperthyroidism characterized by muscle weakness and hypokalemia. All ethnicities can be affected, but TPP typically presents in men of Asian descent. The most common cause of TPP in thyrotoxicosis is Graves' disease. However, TPP can occur with any form of thyrotoxicosis. Up to our knowledge, very few cases ever reported the relationship between TPP and painless thyroiditis. We herein report a 25-yr-old Korean man who suffered from flaccid paralysis of the lower extremities and numbness of hands. The patient was subsequently diagnosed as having TPP associated with transient thyrotoxicosis due to painless thyroiditis. The paralytic attack did not recur after improving the thyroid function. Therefore, it is necessary that early diagnosis of TPP due to transient thyrotoxicosis is made to administer definite treatment and prevent recurrent paralysis.

An unusual cause of muscle weakness: a diagnostic challenge

We report a case of 24 year-old-female presenting with bilateral leg heaviness sensation and difficult walking of one-day duration. Over the past three months she developed progressive and frequent tingling sensation on her hands accompanied by headache and increased thirst. Hypokalemia was identified and treated with resolution of symptoms. She was later found to have Graves' disease. After propranolol and radioiodine therapy no further episodes were reported. Thyrotoxic hypokalemic periodic paralysis is an alarming, potentially lethal, and rare complication of hyperthyroidism. The pathogenesis is uncertain. Because the condition is rare, it is frequently overlooked and misdiagnosed on presentation. It is important to recognize these clinical settings in hypokalemic patients in order to promptly start adequate medical therapy and avoid the lethal complications caused by prolonged sustained potassium depletion.

Periodic paralysis: an unusual presentation of thyrotoxicosis

Thyrotoxic Periodic Paralysis (TPP) is a rare complication of thyrotoxicosis and is up to 20 times more common in males. Cases usually present with painless muscle weakness precipitated by heavy exercise, fasting, an alcohol binge or large carbohydrate meal. Serum potassium is low in the majority, but normokalaemic (or even hyperkalaemic) TPP is recognised. Acute treatment of any electrolyte disorder, administration of a beta-blocker and treatment of the thyrotoxicosis leads to complete resolution. This rare diagnosis should be considered by the Acute Physician when confronted with any case of muscle weakness.