Clinical and genetic analysis of a case of Gitelman syndrome accompanied with Graves disease and adrenocortical adenoma: A case report.

RATIONALE: Gitelman syndrome (GS), also known as familial hypokalemia and hypomagnesemia, is a rare autosomal recessive inherited disease caused by primary renal desalinization caused by impaired reabsorption of sodium and chloride ions in the distal renal tubules. We report a case of clinical and genetic characteristics of GS accompanied with Graves disease and adrenocorticotrophic hormone (ACTH)-independent adrenocortical adenoma. PATIENT CONCERNS: The patient is a 45 year old female, was admitted to our hospital, due to a left adrenal gland occupying lesion as the chief complaint. DIAGNOSIS: The patient was finally diagnosed as GS with Graves disease and adrenocortical adenoma. INTERVENTIONS: Potassium magnesium aspartate (1788 mg/d, taken orally 3 times a day (supplement a few times a day, intake method, treatment duration). Contains 217.2 mg of potassium and 70.8 mg of magnesium, and potassium chloride (4.5 g/d, taken orally 3 times a day (supplement a few times a day, intake method, and treatment duration); Potassium 2356 mg), spironolactone (20 mg/d, taken orally once a day (supplement a few times a day, intake method, treatment duration). After 3 months of treatment, the patient's blood potassium fluctuated between 3.3-3.6 mmol/L, and blood magnesium fluctuated between 0.5-0.7 mmol/L, indicating a relief of fatigue symptoms. OUTCOMES: On the day 6 of hospitalization, the symptoms of dizziness, limb fatigue, fatigue and pain were completely relieved on patient. In the follow-up of the following year, no recurrence of the condition was found. LESSONS: The novel c.1444-10(IVS11)G > A variation may be a splicing mutation. The compound heterozygous mutations of the SLC12A3 gene may be the pathogenic cause of this GS pedigree.

A case of pseudo-Bartter/Gitelman syndrome caused by long-term laxative abuse, leading to end-stage kidney disease.

Pseudo-Bartter/Gitelman syndrome (PBS/PGS) is a disorder that presents with hypokalemia and metabolic alkalosis resembling Gitelman syndrome (GS) due to secondary factors, such as lifestyle and /or medicines. Notably, PBS/PGS is more likely to cause renal dysfunction than GS. We report the first case of PBS/PGS due to long-term laxative abuse leading to end-stage kidney disease (ESKD). The patient was a 49-year-old woman with a history of constipation since school, who had used excessive doses of laxatives on her own judgment for nine years at least from 22 years of age. Two years later, blood tests revealed hypokalemia (serum K 3.1 mEq/L), and nine years later, the patient's renal function began to deteriorate (Cr-eGFR 48.7 mL/min/1.73 m2). Since abuse of laxatives was suspected as the cause, it was changed to the proper dosage of laxatives. At 33 years, the patient developed acute kidney injury (AKI), due to a urinary tract infection, and required intensive treatment, including hemodialysis. Although the patient was eventually weaned off dialysis, the renal function did not recover to pre-AKI levels. In suspected GS, comprehensive genetic testing for renal disease-related genes was performed; however, no obvious pathogenic variants were identified. Thereafter, despite decreasing the laxative doses and potassium supplementation, her renal function continued to decline. At 49 years, the patient developed ESKD and was started on maintenance hemodialysis. PBS/PGS is a disease that can lead to ESKD. An early diagnosis of PBS/PGS is crucial to prevent renal function deterioration, and the underlying causes should be removed immediately.

Interpreting epigenetic causes of recurrent hypokalemia and seizures: Gitelman syndrome co-exist with pseudohypoparathyroidism type 1B.

We describe a unique case of 27-year-old male with Gitelman syndrome (GS) co-exist with pseudohypoparathyroidism type 1B (PHP1B). The patient presented with a 5-year history of seizures, tetany, and numbness of the extremities. Further examinations showed recurrent hypokalemia, inappropriate kaliuresis, hypocalcemia, hyperphosphatemia, and elevated PTH levels. A novel variant of autosomal recessive GS (p.Val287Met SLC12A3) and a novel 492.3Kb deletion containing the whole of STX16, were discovered by a whole-exome sequencing. Following the diagnosis, calcitriol, calcium, and potassium supplements were started. Hematuria calcium and phosphorus levels, as well as blood potassium levels, have recovered and remained within normal ranges after 3 years of follow-up. Our findings have important consequences for supporting the idea that heterozygosity for variants have effects on the patients' clinical performance with autosomal recessive inheritance disorders. Further study is need for the putative effects of the variant. Likewise, further investigation with regards to the gene-gene interaction relations between GS and other electrolyte imbalance disorders is warranted.

Long-Term Indomethacin Treatment in a Chinese Child with Gitelman Syndrome: Case Report and Literature Review on its Efficacy and Tolerance.

BACKGROUND Gitelman syndrome (GS) is a rare inherited autosomal recessive salt-losing renal tubulopathy. Early-onset GS is difficult to differentiate from Bartter syndrome (BS). It has been reported in some cases that cyclooxygenase (COX) inhibitors, which pharmacologically reduce prostaglandin E2(PGE2) synthesis, are helpful for GS patients, especially in children, but the long-term therapeutic effect has not yet been revealed. CASE REPORT A 4-year-old boy was first brought to our hospital for the chief concern of short stature and growth retardation. Biochemical tests demonstrated severe hypokalemia, hyponatremia, and hypochloremic metabolic alkalosis. The patient's serum magnesium was normal. He was diagnosed with BS and treated with potassium supplementation and indomethacin and achieved stable serum potassium levels and slow catch-up growth. At 11.8 years of age, the patient showed hypomagnesemia and a genetic test confirmed that he had GS with compound heterozygous mutations in the SLC12A3 gene. At the age of 14.8 years, when indomethacin had been taken for nearly 10 years, the boy reported having chronic stomachache, while his renal function remained normal. After proton pump inhibitor and acid inhibitor therapy, the patient's symptoms were ameliorated, and he continued to take a low dose of indomethacin (37.5 mg/d divided tid) with good tolerance. CONCLUSIONS Early-onset GS in childhood can be initially misdiagnosed as BS, and gene detection can confirm the final diagnosis. COX inhibitors, such as indomethacin, might be tolerated by pediatric patients, and long-term therapy can improve the hypokalemia and growth retardation without significant adverse effects.

Gitelman syndrome combined with diabetes mellitus: A case report and literature review.

RATIONALE: Gitelman syndrome (GS) is an uncommon autosomal recessive tubulopathy resulting from a functional deletion mutation in the SLC12A3 gene. Its onset is typically insidious and challenging to discern, and it is characterized by hypokalemia, metabolic alkalosis, and reduced urinary calcium excretion. There is limited literature on the diagnosis and management of GS in individuals with concomitant diabetes. PATIENT CONCERNS: A 36-year-old male patient with a longstanding history of diabetes exhibited suboptimal glycemic control. Additionally, he presented with concurrent findings of hypokalemia, hypomagnesemia, hypocalciuria, and metabolic alkalosis. DIAGNOSIS: Building upon the patient's clinical manifestations and extensive laboratory evaluations, we conducted thorough genetic testing, leading to the identification of a compound heterozygous mutation within the SLC12A3 gene. This definitive finding confirmed the diagnosis of GS. INTERVENTIONS: We have formulated a detailed medication regimen for patients, encompassing personalized selection of hypoglycemic medications and targeted electrolyte supplementation. OUTCOMES: Following 1 week of comprehensive therapeutic intervention, the patient's serum potassium level effectively normalized to 3.79 mmol/L, blood glucose parameters stabilized, and there was significant alleviation of clinical symptoms. LESSONS: GS has a hidden onset and requires early diagnosis and intervention based on patient related symptoms and laboratory indicators in clinical practice, and personalized medication plans need to be provided according to the specific situation of the patient.

Novel heterozygous mutations of SLC12A3 gene in a Chinese pedigree with Gitelman syndrome: A care-compliant case report.

RATIONALE: The diagnosis of Gentleman syndrome (GS) is usually delayed because the clinical symptoms are easily mistaken. PATIENT CONCERNS: A 19-year-old male patient was referred to endocrinology due to intermittent twitch of extremities for approximately 7 years. DIAGNOSES: The diagnosis of GS was made based on the laboratory and gene detection results. We identified 2 new variants in the SLC12A3 gene [c.857 A > C (exon7) and c.2089_2095del (exon17)] in his Asian family. INTERVENTIONS: The patient received the treatment of potassium chloride sustained release tablets, potassium magnesium aspartate and spironolactone. After given potassium supplement through enema, his serum potassium level was corrected to normal. OUTCOMES: The electrolyte imbalance including hypokalemia and hypomagnesemia were improved with a remission of the clinical manifestations. But the patient's condition still could not remain stable for his irregular oral potassium supplementation during the follow-up of nearly 3 months. LESSONS: Our finding broadens the variant spectrum of SLC12A3 and contributes to a more quickly genetic counseling. As a result, when a patient presents with persistent, unspecified, and inadequately treated hypokalemia, tests for GS should indeed be considered. For suspected cases of GS, genetic testing should always be considered in the diagnosis.

Spectrum of variants in a large Chinese Gitelman syndrome cohort.

Gitelman syndrome (GS) is caused by SLC12A3 biallelic variants. A previous study showed that large rearrangements (LRGs) of SLC12A3 accounted for the low sensitivity of genetic testing. However, a systematic screening for LRGs in Chinese GS patients is lacking. Massively parallel sequencing (MPS) and multiplex ligation-dependent probe amplification (MLPA) were performed to sequence the genomic DNA of patients with clinically diagnosed GS. Of 165 index cases, MPS identified 151 cases with two or more affected alleles and 14 cases with one variant allele. LRGs were detected by MLPA in 20 out of 27 cases, including 15 cases with suspected LRGs by MPS. Among these 20 cases with LRGs, the results of MPS and MLPA were identical in only 8 cases. Additional LRGs in 6 cases were detected by MLPA alone. In 6 cases, E4_E6del was identified by MPS, while E4_E5del and Intron6del were identified by MLPA. Among the 102 distinct variants, 30 are novel. LRGs were found in 20 cases (12.1%). LRGs were found in 12.1% of our Chinese GS patients cohort. We show that MPS and MLPA are two complementary techniques with the ability to improve the diagnostic yield of GS.

Case report: Gitelman syndrome with diabetes: Confirmed by both hydrochlorothiazide test and genetic testing.

RATIONALE: Gitelman syndrome (GS) is an autosomal recessive tubulopathy caused by mutations of the SLC12A3 gene. It is characterized by hypokalemic metabolic alkalosis, hypomagnesemia and hypocalciuria. Hypokalemia, hypomagnesemia, and increased renin-angiotensin-aldosterone system (RAAS) activity can cause glucose metabolism dysfunction. The diagnosis of GS includes clinical diagnosis, genetic diagnosis and functional diagnosis. The gene diagnosis is the golden criterion while as functional diagnosis is of great value in differential diagnosis. The hydrochlorothiazide (HCT) test is helpful to distinguish GS from batter syndrome, but few cases have been reported to have HCT testing. PATIENT CONCERNS: A 51-year-old Chinese woman presented to emergency department because of intermittent fatigue for more than 10 years. DIAGNOSES: Laboratory test results showed hypokalemia, hypomagnesemia, hypocalciuria and metabolic alkalosis. The HCT test showed no response. Using next-generation and Sanger sequencing, we identified 2 heterozygous missense variants (c.533C > T:p.S178L and c.2582G > A:p.R861H) in the SLC12A3 gene. In addition, the patient was diagnosed with type 2 diabetes mellitus 7 years ago. Based on these findings, the patient was diagnosed with GS with type 2 diabetic mellitus (T2DM). INTERVENTIONS: She was given potassium and magnesium supplements, and dapagliflozin was used to control her blood glucose. OUTCOMES: After treatments, her fatigue symptoms were reduced, blood potassium and magnesium levels were increased, and blood glucose levels were well controlled. LESSONS: When GS is considered in patients with unexplained hypokalemia, the HCT test can be used for differential diagnosis, and genetic testing can be continued to confirm the diagnosis when conditions are available. GS patients often have abnormal glucose metabolism, which is mainly caused by hypokalemia, hypomagnesemia, and secondary activation of RAAS. When a patient is diagnosed with GS and type 2 diabetes, sodium-glucose cotransporter 2 inhibitors (SGLT2i) can be used to control the blood glucose level and assist in raising blood magnesium.

A case report of Gitelman syndrome in children.

RATIONALE: Giltelman syndrome (GS) is an autosomal recessive infectious disease, which is caused by the mutation of SLC12A3 gene encoding thiazide diuretic sensitive sodium chloride cotransporter located in the distal convoluted tubule of the kidney. PATIENT CONCERNS: A 7-year-old and 3-month-old male patient has poor appetite, slow growth in height and body weight since the age of 3, body weight: 16 kg (-3 standard deviation), height: 110 cm (-3 standard deviation), normal exercise ability and intelligence. One year ago, he was diagnosed with hypokalemia. After potassium supplement treatment, the blood potassium returned to normal. The patient developed abdominal pain, vomiting, limb weakness, and tetany 1 day before admission. DIAGNOSES: After admission examination, the patient was found to have hypokalemia (2.27-2.88 mmol/L), hypomagnesemia (0.47 mmol/L), hypophosphatemia (1.17 mmol/L), hypocalcemia (1.06 mmol/24 hours), and metabolic alkalosis (PH 7.60). The blood pressure is normal, and the concentration of aldosterone is 791.63 pg/mL. The adrenocorticotropic hormone and cortisol detected at 8 am are 4.95 pmol/L and 275.09 nmol/L, respectively. Twenty-four hours of urine potassium is 32.52 mmol. Gene sequencing results showed 2 pathogenic variants in the GS-related SLC12A3 gene, which are related to the phenotype of the subject. INTERVENTIONS: After admission, the patients were given potassium and magnesium supplements, as well as oral spironolactone. The symptoms of limb weakness and tetany were significantly relieved. After discharge, the patients continued to maintain treatment to keep the blood potassium at more than 3.0 mmol/L, and the blood magnesium at more than 0.6 mmol/L. OUTCOMES: Follow-up at 1 month after discharge, in the patient's self-description, he had no symptoms such as limb weakness and tetany, and his height was increased by 1 cm and the body weight increased by 1.5 kg. LESSONS: For patients with hypokalemia, hypomagnesemia, and metabolic alkalosis, the possibility of GS should be given priority. After the diagnosed by gene sequencing of SLC12A3 gene, potassium and magnesium supplementation could significantly improve symptoms.

Gitelman syndrome in pregnancy: a case series.

OBJECTIVE: To evaluate maternal and fetal outcomes in women with Gitelman syndrome (GS). METHODS: Retrospective analysis of the clinical data of five patients with the clinical diagnosis of GS during pregnancy, who were admitted to Beijing Shijitan Hospital, Capital Medical University between 2013 and 2019, was conducted. RESULTS: Five women with GS during pregnancy who finally gave birth to a total of eight newborns have been included. Three cases were primiparas and two cases were multiparas. Two cases were diagnosed before pregnancy and three cases were diagnosed in first or second trimester. The primary treatment was oral or intravenous electrolytes supplement. Three patients delivered through the vagina, and shoulder dystocia occurred in one patient. Two patients delivered by cesarean section, with one because of symptom of limb weakness during the course of labor and the other owing to gestational diabetes with fetal macrosomia. Postpartum hemorrhage and urinary retention were not reported in these cases. In perinatal period all the infants had good outcome. The children, aged between six months and five years, were healthy and well-developed during follow-up. CONCLUSION: The maternal and perinatal outcome is usually favorable. We should pay attention to electrolyte examination in the first trimester in order to diagnose and manage the GS efficiently. Well-controlled patients with Gitelman syndrome can deliver through the vagina.

Difficulties in the management of hypokalemia in a pregnant patient with Gitelman syndrome.

Gitelman syndrome (GS) is a rare renal disorder, and little is known about its impact on pregnancy. We report the successful outcome of pregnancy in a patient with GS that was managed with aggressive oral and intravenous potassium supplementation.

Molecular Basis, Diagnostic Challenges and Therapeutic Approaches of Bartter and Gitelman Syndromes: A Primer for Clinicians.

Gitelman and Bartter syndromes are rare inherited diseases that belong to the category of renal tubulopathies. The genes associated with these pathologies encode electrolyte transport proteins located in the nephron, particularly in the Distal Convoluted Tubule and Ascending Loop of Henle. Therefore, both syndromes are characterized by alterations in the secretion and reabsorption processes that occur in these regions. Patients suffer from deficiencies in the concentration of electrolytes in the blood and urine, which leads to different systemic consequences related to these salt-wasting processes. The main clinical features of both syndromes are hypokalemia, hypochloremia, metabolic alkalosis, hyperreninemia and hyperaldosteronism. Despite having a different molecular etiology, Gitelman and Bartter syndromes share a relevant number of clinical symptoms, and they have similar therapeutic approaches. The main basis of their treatment consists of electrolytes supplements accompanied by dietary changes. Specifically for Bartter syndrome, the use of non-steroidal anti-inflammatory drugs is also strongly supported. This review aims to address the latest diagnostic challenges and therapeutic approaches, as well as relevant recent research on the biology of the proteins involved in disease. Finally, we highlight several objectives to continue advancing in the characterization of both etiologies.

The Dietary Approach to the Treatment of the Rare Genetic Tubulopathies Gitelman's and Bartter's Syndromes.

Gitelman's (GS) and Bartter's (BS) syndromes are rare, inherited autosomal recessive tubulopathies characterized by hypokalemia, metabolic alkalosis, renal sodium, chloride, and potassium and magnesium-wasting. While the treatment based on potassium, sodium, chloride, and magnesium supplementation in addition to other pharmacologic options are widely established, recommendations about the dietary approach to GS and BS still remain generic. In this review we focus on the dietary strategies to increase sodium, potassium, and magnesium intake in GS and BS patients. Potassium and magnesium-rich foods and supplements are considered together with those that may reduce through different mechanisms the potassium and magnesium plasma level. Magnesium supplementation is often poorly tolerated, causing abdominal pain and diarrhea in most patients. New formulations using liposome and, in particular, sucrosomial technology have been recently proposed for magnesium supplementation in order to increase magnesium supplement tolerability and intestinal absorption. The dietary approach to GS and BS may be very important in the therapeutic approach to these syndromes. Due to the relevance of the dietary approach to these syndromes, a nutritional counseling should always be recommended and the nutritionist should join nephrologists in the follow-up of GS and BS patient care.

A novel compound heterozygous variant of the SLC12A3 gene in Gitelman syndrome with diabetes and the choices of the appropriate hypoglycemic drugs: a case report.

BACKGROUND: Gitelman syndrome (GS) is an autosomal recessive tubulopathy caused by mutations of the SLC12A3 gene. It is characterized by hypokalemic metabolic alkalosis, hypomagnesemia and hypocalciuria. It is universally known that both hypokalemia and hypomagnesemia can influence insulin secretion and insulin resistance, but the exact mechanisms require further study. We identified a novel deletion variant of the SLC12A3 gene and discussed the appropriate hypoglycemic drugs in Gitelman syndrome (GS) patients with type 2 diabetes. CASE PRESENTATION: A 55-year-old diabetic female patient was hospitalized for evaluation because of paroxysmal general weakness and numbness of extremities for one year. We suspected that she was suffering from GS by initial estimation. Direct Sanger sequencing was used to analyze the causative gene SLC12A3 of GS. Oral glucose tolerance test (OGTT) was carried out to assess the glucose metabolism and insulin resistance status. Genetic analysis revealed that she was a compound heterozygote for a recurrent missense mutation c.179C > T and a novel deletion c.1740delC in SLC12A3, thus her diagnosis of GS was confirmed. The patient was treated with potassium chloride (3.0 g/d) and magnesium chloride (element magnesium 350 mg/d) on the basis of initial treatment of diabetes with hypoglycemic drug (Repaglinide, 3.0 mg/day). However, she developed frequent hypoglycemia after one week. OGTT showed that her glucose metabolism and insulin resistance much improved after potassium and magnesium supplemental therapy. Then we changed the hypoglycemic agent to a dipeptidyl peptidase-4 (DPP-4) inhibitor (Trajenta 5 mg/d), since then her blood glucose level remained normal during two-year of follow-up. CONCLUSION: We have identified a novel deletion of the SLC12A3 gene and discussed the appropriate hypoglycemic drugs in Gitelman syndrome (GS) patients with type 2 diabetes. We suggested that attention need to be paid to blood glucose monitoring in GS patients, especially when hypokalemia and hypomagnesemia are corrected. Besides, the insufficient blood volume and serum electrolyte disturbance should also be taken into consideration in the selecting hypoglycemic drugs for GS patients.

Gitelman Syndrome in Pregnancy: A Clinical Challenge.

PURPOSE: Disease progress may be affected by pregnancy-related changes, and underlying conditions may also affekt pregnancy outcomes in women with Gitelman syndrome (GS). Case presentation A 35-year-old woman with GS (gravida 2 para 1) was referred to our hospital to start routine antenatal care follow-up at 6 weeks of gestation. At the age of 31, she had been diagnosed with GS after her first uneventful pregnancy. Upon early admission, her serum Mg+level was 0.51 mmol/L and her serum K+level 2.7 mmol/L with normal kidney function tests. She was already taking oral combined potassium citrate and potassium bicarbonate supplementation once a day before pregnancy. At the eighth gestational week, the medication was changed to an oral potassium color sachet of 1.5 gram per day until labor because of the insufficient dosage to maintain optimum potassium levels. She was also taking 365 milligrams of oral magnesium oxide twice a day before and during pregnancy. In the third trimester of the pregnancy, her serum Mg+level was 0.48 mmol/L and serum K+level 2.8 mmol/L. Because of the previous uterine surgery history, she underwent an elective cesarean operation at 39 weeks' gestation under spinal anesthesia and delivered a healthy 3090-gram female infant. CONCLUSION: Increased need for potassium and magnesium supplementation should be the critical considerations when managing pregnant patients with GS.

Anesthetic management of child with Gitelman Syndrome: case report.

Gitelman syndrome is a rare autosomal recessive inherited disease that affects the thiazidesensitive sodium-chloride cotransport channels and the magnesium channels in the distal convoluted tubule, leading to hypokalemic metabolic alkalosis, hypomagnesemia and hypocalciuria. There is no cure for this condition and supportive treatment relies on ionic supplementation and symptom management. Literature regarding the anesthetic approach is scarce. This case report presents the anesthetic management of a child with Gitelman syndrome and its difficult electrolyte optimization.

Hypokalaemic paralysis and metabolic alkalosis in a patient with Sjögren syndrome: a case report and literature review.

BACKGROUND: Acquired Gitelman syndrome is a very rare disorder reported in association with autoimmune disorders, mostly Sjögren syndrome. It is characterized by the presence of hypokalaemic metabolic alkalosis, hypocalciuria, hypomagnesaemia and hyper-reninaemia, in the absence of typical genetic mutations associated with inherited Gitelman syndrome. CASE PRESENTATION: A 20 year old woman who was previously diagnosed with primary Sjögren syndrome and autoimmune thyroiditis presented with two week history of lower limb weakness and salt craving. Examination revealed upper limb and lower limb muscle weakness with muscle power of 3/5 on MRC scale and diminished deep tendon reflexes. On evaluation, she had hypokalaemia with high trans-tubular potassium gradient, metabolic alkalosis and hypocalciuria, features suggestive of Gitelman syndrome. New onset hypokalaemic alkalosis in a previously normokalaemic patient with Sjögren syndrome strongly favored a diagnosis of acquired Gitelman syndrome. Daily potassium supplementation and spironolactone resulted in complete clinical recovery. CONCLUSIONS: Acquired Gitelman syndrome associated with Sjögren syndrome is rare. It should be considered as a differential diagnosis during evaluation of acute paralysis and hypokalaemic metabolic alkalosis in patients with autoimmune disorders, especially Sjögren syndrome.

Diagnosis and outpatient management of Gitelman syndrome from the first trimester of pregnancy.

A 32-year-old woman presented with an incidental finding of hypokalaemia on routine bloods at 9 weeks of a second pregnancy, on a background of lifelong salt craving. Her previous pregnancy was uncomplicated. She had no previous significant medical or family history. Venous blood gases showed a hypokalaemic, normochloraemic metabolic alkalosis. Urinary potassium was elevated. Escalating doses of oral supplementation of potassium, magnesium, sodium and potassium-sparing diuretics were required through the course of pregnancy, in response to regular electrolyte monitoring. These were later weaned and completely stopped post partum. Delivery was uneventful with no maternal or neonatal complications. Genetic testing performed post partum showed heterogenous mutation of SCL12A3 gene.

Type-5 Bartter syndrome presenting with metabolic seizure in adulthood.

Bartter syndrome is a very rare and heterogeneous disease with variable age of onset and symptom severity. Genotypically they have inherited disorders of the thick ascending limb in the renal tubular system, which manifest phenotypically as electrolyte imbalance due to loss of sodium, chloride and potassium. Gain of function mutations in the calcium-sensing receptor has been described in some patients with Bartter's syndrome (type-5 Bartter syndrome or autosomal dominant hypocalcaemia with Bartter syndrome) associated with hypocalcaemia and hypercalciuria differentiating it from Gitelman syndrome. This phenotype has been reported to present in adulthood with metabolic abnormalities. We present a case of a middle-aged woman who presented with metabolic seizures and on evaluation was found to have profound electrolyte abnormalities which were corrected with supplements and led to the resolution of symptoms.

Novel SLC12A3 mutation in Gitelman syndrome.

Gitelman syndrome (GS) is an autosomal recessive disease characterised by the presence of hypokalaemic metabolic alkalosis with hypomagnesaemia and hypocalciuria. The prevalence of this disease is 1-10/40 000. GS is usually associated with mild and non-specific symptoms and many patients are only diagnosed in adulthood. The disease is caused by mutations in the SLC12A3 gene. We present the case of a 49-year-old man referred to a nephrology appointment due to persistent hypokalaemia and hypomagnesaemia. Complementary evaluation revealed hypokalaemia, hypomagnesaemia, metabolic alkalosis, hyperreninaemia, increased chloride and sodium urinary excretion, and reduced urinary calcium excretion. Renal function, remainder serum and urinary ionogram, and renal ultrasound were normal. A diagnosis of GS was established and confirmed with genetic testing which revealed a novel mutation in SLC12A3 (c.1072del, p.(Ala358Profs*12)). This novel mutation extends the spectrum of known SLC12A3 gene mutations and further supports the allelic heterogeneity of GS.