Backgound Bartter's syndrome(BS)is a rare group of salt losing tubulopathies due to the impairment of transport mecha-nisms at the thick ascending limb of the Henle's loop.Data sources Literature reviews and o...Backgound Bartter's syndrome(BS)is a rare group of salt losing tubulopathies due to the impairment of transport mecha-nisms at the thick ascending limb of the Henle's loop.Data sources Literature reviews and original research articles were collected from database,including PubMed and Scopus.Results According to the time of onset and symptoms,BS can be classified into antenatal and classic BS.Molecular studies have identified different subtypes of BS.BS types Ⅰ,Ⅱ and Ⅲ are caused by mutations on genes encoding the luminal Na^(+)-K^(+)-2Cl^(-) co-transporter,the luminal K+ channel ROMK,and the basolateral chloride channel ClC-Kb(CLCNKB),respectively.Loss-of-function mutations of Barttin CLCNK type accessory beta subunit cause BS type Ⅳa.Simultaneous mutations of CLCNKB and CLCNKA cause BS type Ⅳb.BS type Ⅴ consists in a novel transient form characterized by antenatal presentation due to mutations in the MAGE family member D2.Severe gain-of-function mutations of the extracellular calcium sensing receptor gene can result in an autosomal dominant condition of BS.Main clinical and biochemical alterations in BS include polyuria,dehydration,hypokalemia,hypochloremic metabolic alka-losis,hyperreninemia,high levels of prostaglandins,normal or low blood pressure,hypercalciuria and failure to thrive.Treatment focuses mainly at correcting dehydration and electrolyte disturbances and in measures to reduce polyuria,including the use of nonsteroidal anti-inflammatory medications to control excessive renal prostaglandin E2 production.Conclusions Early diagnosis and treatment of BS may prevent long-term consequences such as growth failure,nephrocal-cinosis and end-stage renal disease.展开更多
目的探讨家族性低镁血症高钙尿症与肾钙质沉着症(familial hypomagnesaemia with hypercalciuria and nephrocalcinosis,FHHNC)患者的临床特点和致病基因特征。方法2016年2月收治1例女性患者,年龄24岁。入院前1个月外院腹部X线片(...目的探讨家族性低镁血症高钙尿症与肾钙质沉着症(familial hypomagnesaemia with hypercalciuria and nephrocalcinosis,FHHNC)患者的临床特点和致病基因特征。方法2016年2月收治1例女性患者,年龄24岁。入院前1个月外院腹部X线片(KUB)检查示左肾结石,双肾钙质沉着。患者于外院行经皮肾镜取石术清除大部分左肾结石。本次入院后实验室检查:血镁0.65 mmol/L,24 h尿钙364.0 mg,血甲状旁腺激素187.4 pg/ml,血肌酐101.5μmol/L。行输尿管软镜碎石术清除左肾残余结石。考虑患者为FHHNC,对患者及其父母行外周血CLDN16和CLDN19基因测序分析。结果基因测序结果显示患者CLDN16基因的第2外显子第123密码子一个碱基缺失(c.368delA),第2外显子第139密码子发生错义突变[c.416C→T(p.A139V)]。患者母亲的第139密码子第2个碱基胞嘧啶变为胸腺嘧啶(c.416C→T);患者父亲的第123密码子第2个碱基腺嘌呤缺失(c.368delA)。该患者确诊为FHHNC,口服氢氯噻嗪、枸橼酸钾、钙镁片治疗。随访6个月,复查血镁1.0 mmol/L,24 h尿钙156.0 mg,血甲状旁腺激素139.6 pg/ml,泌尿系结石无复发,双肾钙质沉着症及肾功能损伤无明显加重。结论CLDN16基因复合杂合突变致FHHNC的临床三联症为低镁血症、高钙尿症和肾钙质沉着症,确诊依靠CLDN16和CLDN19基因测序。肾功能严重受损前以对症治疗为主,给予氢氯噻嗪、枸橼酸钾、钙镁片治疗有可能明显改善低镁血症和高钙尿症。展开更多
早产儿是发生钙磷代谢紊乱的高危人群。维生素D,甲状旁腺素,喂养方式等均可影响早产儿的钙磷代谢状况。常见的钙磷代谢紊乱性疾病主要有代谢性骨病(metabolic bone disease,MBD),肾钙质沉着症(nephrocalcinosis,NC)等。MBD主要由宫内钙...早产儿是发生钙磷代谢紊乱的高危人群。维生素D,甲状旁腺素,喂养方式等均可影响早产儿的钙磷代谢状况。常见的钙磷代谢紊乱性疾病主要有代谢性骨病(metabolic bone disease,MBD),肾钙质沉着症(nephrocalcinosis,NC)等。MBD主要由宫内钙磷储备不足所致,血碱性磷酸酶及血磷水平结合诊断MBD敏感性高,适量维生素D摄入及被动肢体运动有助其预防。NC发病原因复杂,高钙尿是其主要危险因素。其诊断首选B超,治疗则尚待研究。展开更多
Medullary Nephrocalcinosis (MNC) is defined as calcium deposition in tubular basement membrane and interstitium of the kidney medulla. It is 20 times more common than cortical one. In this case report, we present a 12...Medullary Nephrocalcinosis (MNC) is defined as calcium deposition in tubular basement membrane and interstitium of the kidney medulla. It is 20 times more common than cortical one. In this case report, we present a 12-year-boy who presented with persistent nocturnal enuresis for 8 years. Physical examination and routine tests were normal except for microscopic hematuria. Renal ultrasound showed extensive MNC. Twenty-four-hour urine collection revealed normal mineral metabolic screen with low urinary excretion of calcium, phosphorous, magnesium and uric acid yet high for oxalates. Hence, and based on the above-mentioned data, certain metabolic disorders were ruled out: 1) hyperparathyroidism, 2) excessive intake of vitamin D, 3) hypercalcemia, 4) hypercalciuria, 5) hyperuricemia, 6) hyperuricosuria, 7) hypocitraturia, 8) cystinuria, 9) lysinuria and 10) distal renal tubular acidosis were ruled out. Subsequently, urine testing showed high concentration of glycolate with low glycerate and 4-hydroxy-2-oxoglutarates establishing diagnosis of type 1 primary hyperoxaluria (PH I). Further confirmatory tests included: 1) kidney biopsy which showed typical crystals deposition, 2) liver biopsy that confirmed deficiency of the liver-specific peroxisomal enzyme alanine: glyoxylate aminotransferase (AGXT), and 3) full gene analysis that confirmed gene mutation. In conclusion, our case report provides practical algorithm for establishing diagnosis in MNC which is not renal-limited and its prognosis depends upon the underlying etiology.展开更多
Hyperoxaluria can cause not only nephrolithiasis and nephrocalcinosis,but also renal parenchymal disease histologically characterized by deposition of calcium oxalate crystals throughout the renal parenchyma,profound ...Hyperoxaluria can cause not only nephrolithiasis and nephrocalcinosis,but also renal parenchymal disease histologically characterized by deposition of calcium oxalate crystals throughout the renal parenchyma,profound tubular damage and interstitial inflammation and fibrosis.Hyperoxaluric nephropathy presents clinically as acute or chronic renal failure that may progress to endstage renal disease(ESRD).This sequence of events,well recognized in the past in primary and enteric hyperoxalurias,has also been documented in a few cases of dietary hyperoxaluria.Estimates of oxalate intake in patients with chronic dietary hyperoxaluria who developed chronic kidney disease or ESRD were comparable to the reported average oxalate content of the diets of certain populations worldwide,thus raising the question whether dietary hyperoxaluria is a primary cause of ESRD in these regions.Studies addressing this question have the potential of improving population health and should be undertaken,alongside ongoing studies which are yielding fresh insights into the mechanisms of intestinal absorption and renal excretion of oxalate,and into the mechanisms of development of oxalate-induced renal parenchymal disease.Novel preventive and therapeutic strategies for treating all types of hyperoxaluria are expected to develop from these studies.展开更多
<strong>Background:</strong> Medullary sponge kidney (MSK) is a disturbance of renal development characterized by cystic dilation and diffuse precalyceal duct ectasia. The disease affects both genders in e...<strong>Background:</strong> Medullary sponge kidney (MSK) is a disturbance of renal development characterized by cystic dilation and diffuse precalyceal duct ectasia. The disease affects both genders in equal proportions and is generally diagnosed in adulthood, as a result of recurrent calcium nephrolithiasis and nephrocalcinosis. The most frequently encountered manifestations being renal colic, microscopic or macroscopic hematuria, and fever. The intravenous pyelogram is standard for diagnosis and metabolic workup is required to identify the underlying cause. The main goal of treatment is to prevent recurrence and disease progression. Though considered a benign condition, a nephrectomy may often be required in patients presenting late with irreversible complications and end-stage renal disease.<strong> Aim:</strong> To highlight and discuss the presentation and management of a rare case of nephrocalcinosis and nephrolithiasis secondary to the medullary sponge kidney. <strong>Case presentation:</strong> We report herein the case of a 56-year-old male with long-standing hematuria in whom a diagnosis of medullary sponge kidney disease was made and he underwent a left total nephrectomy. The postoperative course was uneventful. <strong>Conclusion:</strong> Nephrocalcinosis and nephrolithiasis are complications of MSK and can result in irreversible renal damage. A high index of suspicion is necessary for patients presenting with renal colic, recurrent urinary tract infections, or hematuria for prompt diagnosis and management.展开更多
In human nephrolithiasis, most stones are containing calcium and are located within urinary cavities; they may contain monohydrate calcium oxalate, dihydrate calcium oxalate and/or calcium phosphates in various propor...In human nephrolithiasis, most stones are containing calcium and are located within urinary cavities; they may contain monohydrate calcium oxalate, dihydrate calcium oxalate and/or calcium phosphates in various proportion. Nephrolithiasis may also be associated with nephrocalcinosis, i.e., crystal depositions in tubular lumen and/or interstitium, an entity which suggests specific pathological processes. Several rodents models have been developed in order to study the pathophysiology of intrarenal crystal formation. We review here calcium rodent models classified upon the presence of nephrolithiasis and/or nephrocalcinosis. As rodents are not prone to nephrolithiasis, models require the induction of a long standing hypercalciuria or hyperoxaluria(thus explaining the very few studies reported), conversely to nephrocalcinosis which may occur within hours or days. Whereas a nephrotoxicity leading to tubular injury and regeneration appears as a critical event for crystal retention in nephrocalcinosis models, surprisingly very little is known about the physiopathology of crystal attachment to urothelium in nephrolithiasis. Creating new models of nephrolithiasis especially in different genetic mice strains appears an important challenge in order to unravel the early mechanisms of urinary stone formation in papilla and fornices.展开更多
BACKGROUND Acute phosphate nephropathy(APN)is a disease that can occur when exposed to high doses of phosphate.The most common cause of APN is the use of oral sodium phosphate for bowel cleansing preparations.However,...BACKGROUND Acute phosphate nephropathy(APN)is a disease that can occur when exposed to high doses of phosphate.The most common cause of APN is the use of oral sodium phosphate for bowel cleansing preparations.However,there are other less commonly known sources of phosphate that are equally important.To date,our literature search did not identify any report of excessive dietary phosphate as a cause of APN.CASE SUMMARY We report an unusual case of a 39-year-old diabetic male who presented with epigastric pain and oliguria.Work-up showed elevated serum creatinine,potassium,and calcium-phosphate product,and metabolic acidosis.The patient was admitted in the intensive care unit and received emergent renal replacement therapy.Kidney biopsy revealed tubular cell injury with transparent crystal casts positive for Von Kossa staining,which established the diagnosis of APN.CONCLUSION This case confirmed that APN may occur with other sources of phosphorus,highlighting the importance of good history taking and kidney biopsy in patients with predisposing factors for APN.Raising awareness on the possibility of APN and its timely recognition and management is imperative so that appropriate measures can be instituted to prevent or delay its progression to end stage renal disease.展开更多
Renal tubular acidosis(RTA)can lead to renal calcification in children,which can cause various complications and impair renal function.This review provides pediatricians with a comprehensive understanding of the relat...Renal tubular acidosis(RTA)can lead to renal calcification in children,which can cause various complications and impair renal function.This review provides pediatricians with a comprehensive understanding of the relationship between RTA and renal calcification,highlighting essential aspects for clinical manage-ment.The article analyzed relevant studies to explore the prevalence,risk factors,underlying mechanisms,and clinical implications of renal calcification in children with RTA.Results show that distal RTA(type 1)is particularly associated with nephrocalcinosis,which presents a higher risk of renal calcification.However,there are limitations to the existing literature,including a small number of studies,heterogeneity in methodologies,and potential publication bias.Longitudinal data and control groups are also lacking,which limits our understanding of longterm outcomes and optimal management strategies for children with RTA and renal calcification.Pediatricians play a crucial role in the early diagnosis and management of RTA to mitigate the risk of renal calcification and associated complications.In addition,alkaline therapy remains a cornerstone in the treatment of RTA,aimed at correcting the acid-base imbalance and reducing the formation of kidney stones.Therefore,early diagnosis and appropriate therapeutic interventions are paramount in preventing and managing renal calcification to preserve renal function and improve long-term outcomes for affected children.Further research with larger sample sizes and rigorous methodologies is needed to optimize the clinical approach to renal calcification in the context of RTA in the pediatric population.展开更多
Background:Familial hypomagnesemia with hypercalciuria and nephrocalcinosis(FHHNC)is an autosomal recessive tubular disease caused by mutations in the CLDN16 or CLDN19 gene.Previous studies using microsatellite marker...Background:Familial hypomagnesemia with hypercalciuria and nephrocalcinosis(FHHNC)is an autosomal recessive tubular disease caused by mutations in the CLDN16 or CLDN19 gene.Previous studies using microsatellite markers flanking the CLDN19 locus estimated that p.G20D(c.59G>A),a recurrent mutation in Spanish families,is a founder mutation.In the present study,we assessed the haplotype of Spanish patients using single nucleotide polymorphisms(SNPs).Methods:Twenty-seven FHHNC patients were included in this study.We analyzed four SNPs located in CLDN19 introns 3 and 4 by polymerase chain reaction amplification and DNA sequencing.Results:Three new patients with homozygous p.G20D were identified.The SNP genotyping analysis showed that alleles carrying this mutation shared a common SNP haplotype.Conclusions:Our findings suggest the existence of a founder effect responsible for FHHNC in our cohort.Testing for the presence of mutation p.G20D should be the first genetic screening in Spanish patients.展开更多
文摘Backgound Bartter's syndrome(BS)is a rare group of salt losing tubulopathies due to the impairment of transport mecha-nisms at the thick ascending limb of the Henle's loop.Data sources Literature reviews and original research articles were collected from database,including PubMed and Scopus.Results According to the time of onset and symptoms,BS can be classified into antenatal and classic BS.Molecular studies have identified different subtypes of BS.BS types Ⅰ,Ⅱ and Ⅲ are caused by mutations on genes encoding the luminal Na^(+)-K^(+)-2Cl^(-) co-transporter,the luminal K+ channel ROMK,and the basolateral chloride channel ClC-Kb(CLCNKB),respectively.Loss-of-function mutations of Barttin CLCNK type accessory beta subunit cause BS type Ⅳa.Simultaneous mutations of CLCNKB and CLCNKA cause BS type Ⅳb.BS type Ⅴ consists in a novel transient form characterized by antenatal presentation due to mutations in the MAGE family member D2.Severe gain-of-function mutations of the extracellular calcium sensing receptor gene can result in an autosomal dominant condition of BS.Main clinical and biochemical alterations in BS include polyuria,dehydration,hypokalemia,hypochloremic metabolic alka-losis,hyperreninemia,high levels of prostaglandins,normal or low blood pressure,hypercalciuria and failure to thrive.Treatment focuses mainly at correcting dehydration and electrolyte disturbances and in measures to reduce polyuria,including the use of nonsteroidal anti-inflammatory medications to control excessive renal prostaglandin E2 production.Conclusions Early diagnosis and treatment of BS may prevent long-term consequences such as growth failure,nephrocal-cinosis and end-stage renal disease.
文摘早产儿是发生钙磷代谢紊乱的高危人群。维生素D,甲状旁腺素,喂养方式等均可影响早产儿的钙磷代谢状况。常见的钙磷代谢紊乱性疾病主要有代谢性骨病(metabolic bone disease,MBD),肾钙质沉着症(nephrocalcinosis,NC)等。MBD主要由宫内钙磷储备不足所致,血碱性磷酸酶及血磷水平结合诊断MBD敏感性高,适量维生素D摄入及被动肢体运动有助其预防。NC发病原因复杂,高钙尿是其主要危险因素。其诊断首选B超,治疗则尚待研究。
文摘Medullary Nephrocalcinosis (MNC) is defined as calcium deposition in tubular basement membrane and interstitium of the kidney medulla. It is 20 times more common than cortical one. In this case report, we present a 12-year-boy who presented with persistent nocturnal enuresis for 8 years. Physical examination and routine tests were normal except for microscopic hematuria. Renal ultrasound showed extensive MNC. Twenty-four-hour urine collection revealed normal mineral metabolic screen with low urinary excretion of calcium, phosphorous, magnesium and uric acid yet high for oxalates. Hence, and based on the above-mentioned data, certain metabolic disorders were ruled out: 1) hyperparathyroidism, 2) excessive intake of vitamin D, 3) hypercalcemia, 4) hypercalciuria, 5) hyperuricemia, 6) hyperuricosuria, 7) hypocitraturia, 8) cystinuria, 9) lysinuria and 10) distal renal tubular acidosis were ruled out. Subsequently, urine testing showed high concentration of glycolate with low glycerate and 4-hydroxy-2-oxoglutarates establishing diagnosis of type 1 primary hyperoxaluria (PH I). Further confirmatory tests included: 1) kidney biopsy which showed typical crystals deposition, 2) liver biopsy that confirmed deficiency of the liver-specific peroxisomal enzyme alanine: glyoxylate aminotransferase (AGXT), and 3) full gene analysis that confirmed gene mutation. In conclusion, our case report provides practical algorithm for establishing diagnosis in MNC which is not renal-limited and its prognosis depends upon the underlying etiology.
文摘Hyperoxaluria can cause not only nephrolithiasis and nephrocalcinosis,but also renal parenchymal disease histologically characterized by deposition of calcium oxalate crystals throughout the renal parenchyma,profound tubular damage and interstitial inflammation and fibrosis.Hyperoxaluric nephropathy presents clinically as acute or chronic renal failure that may progress to endstage renal disease(ESRD).This sequence of events,well recognized in the past in primary and enteric hyperoxalurias,has also been documented in a few cases of dietary hyperoxaluria.Estimates of oxalate intake in patients with chronic dietary hyperoxaluria who developed chronic kidney disease or ESRD were comparable to the reported average oxalate content of the diets of certain populations worldwide,thus raising the question whether dietary hyperoxaluria is a primary cause of ESRD in these regions.Studies addressing this question have the potential of improving population health and should be undertaken,alongside ongoing studies which are yielding fresh insights into the mechanisms of intestinal absorption and renal excretion of oxalate,and into the mechanisms of development of oxalate-induced renal parenchymal disease.Novel preventive and therapeutic strategies for treating all types of hyperoxaluria are expected to develop from these studies.
文摘<strong>Background:</strong> Medullary sponge kidney (MSK) is a disturbance of renal development characterized by cystic dilation and diffuse precalyceal duct ectasia. The disease affects both genders in equal proportions and is generally diagnosed in adulthood, as a result of recurrent calcium nephrolithiasis and nephrocalcinosis. The most frequently encountered manifestations being renal colic, microscopic or macroscopic hematuria, and fever. The intravenous pyelogram is standard for diagnosis and metabolic workup is required to identify the underlying cause. The main goal of treatment is to prevent recurrence and disease progression. Though considered a benign condition, a nephrectomy may often be required in patients presenting late with irreversible complications and end-stage renal disease.<strong> Aim:</strong> To highlight and discuss the presentation and management of a rare case of nephrocalcinosis and nephrolithiasis secondary to the medullary sponge kidney. <strong>Case presentation:</strong> We report herein the case of a 56-year-old male with long-standing hematuria in whom a diagnosis of medullary sponge kidney disease was made and he underwent a left total nephrectomy. The postoperative course was uneventful. <strong>Conclusion:</strong> Nephrocalcinosis and nephrolithiasis are complications of MSK and can result in irreversible renal damage. A high index of suspicion is necessary for patients presenting with renal colic, recurrent urinary tract infections, or hematuria for prompt diagnosis and management.
文摘In human nephrolithiasis, most stones are containing calcium and are located within urinary cavities; they may contain monohydrate calcium oxalate, dihydrate calcium oxalate and/or calcium phosphates in various proportion. Nephrolithiasis may also be associated with nephrocalcinosis, i.e., crystal depositions in tubular lumen and/or interstitium, an entity which suggests specific pathological processes. Several rodents models have been developed in order to study the pathophysiology of intrarenal crystal formation. We review here calcium rodent models classified upon the presence of nephrolithiasis and/or nephrocalcinosis. As rodents are not prone to nephrolithiasis, models require the induction of a long standing hypercalciuria or hyperoxaluria(thus explaining the very few studies reported), conversely to nephrocalcinosis which may occur within hours or days. Whereas a nephrotoxicity leading to tubular injury and regeneration appears as a critical event for crystal retention in nephrocalcinosis models, surprisingly very little is known about the physiopathology of crystal attachment to urothelium in nephrolithiasis. Creating new models of nephrolithiasis especially in different genetic mice strains appears an important challenge in order to unravel the early mechanisms of urinary stone formation in papilla and fornices.
文摘BACKGROUND Acute phosphate nephropathy(APN)is a disease that can occur when exposed to high doses of phosphate.The most common cause of APN is the use of oral sodium phosphate for bowel cleansing preparations.However,there are other less commonly known sources of phosphate that are equally important.To date,our literature search did not identify any report of excessive dietary phosphate as a cause of APN.CASE SUMMARY We report an unusual case of a 39-year-old diabetic male who presented with epigastric pain and oliguria.Work-up showed elevated serum creatinine,potassium,and calcium-phosphate product,and metabolic acidosis.The patient was admitted in the intensive care unit and received emergent renal replacement therapy.Kidney biopsy revealed tubular cell injury with transparent crystal casts positive for Von Kossa staining,which established the diagnosis of APN.CONCLUSION This case confirmed that APN may occur with other sources of phosphorus,highlighting the importance of good history taking and kidney biopsy in patients with predisposing factors for APN.Raising awareness on the possibility of APN and its timely recognition and management is imperative so that appropriate measures can be instituted to prevent or delay its progression to end stage renal disease.
文摘Renal tubular acidosis(RTA)can lead to renal calcification in children,which can cause various complications and impair renal function.This review provides pediatricians with a comprehensive understanding of the relationship between RTA and renal calcification,highlighting essential aspects for clinical manage-ment.The article analyzed relevant studies to explore the prevalence,risk factors,underlying mechanisms,and clinical implications of renal calcification in children with RTA.Results show that distal RTA(type 1)is particularly associated with nephrocalcinosis,which presents a higher risk of renal calcification.However,there are limitations to the existing literature,including a small number of studies,heterogeneity in methodologies,and potential publication bias.Longitudinal data and control groups are also lacking,which limits our understanding of longterm outcomes and optimal management strategies for children with RTA and renal calcification.Pediatricians play a crucial role in the early diagnosis and management of RTA to mitigate the risk of renal calcification and associated complications.In addition,alkaline therapy remains a cornerstone in the treatment of RTA,aimed at correcting the acid-base imbalance and reducing the formation of kidney stones.Therefore,early diagnosis and appropriate therapeutic interventions are paramount in preventing and managing renal calcification to preserve renal function and improve long-term outcomes for affected children.Further research with larger sample sizes and rigorous methodologies is needed to optimize the clinical approach to renal calcification in the context of RTA in the pediatric population.
基金supported by a research grant(PI11/00342)from Fondo de Investigacion Sanitaria(co-funded by the European Regional Development Fund,"A way to build Europe")to F.C.M.This funding was granted as coordinated project Renaltube
文摘Background:Familial hypomagnesemia with hypercalciuria and nephrocalcinosis(FHHNC)is an autosomal recessive tubular disease caused by mutations in the CLDN16 or CLDN19 gene.Previous studies using microsatellite markers flanking the CLDN19 locus estimated that p.G20D(c.59G>A),a recurrent mutation in Spanish families,is a founder mutation.In the present study,we assessed the haplotype of Spanish patients using single nucleotide polymorphisms(SNPs).Methods:Twenty-seven FHHNC patients were included in this study.We analyzed four SNPs located in CLDN19 introns 3 and 4 by polymerase chain reaction amplification and DNA sequencing.Results:Three new patients with homozygous p.G20D were identified.The SNP genotyping analysis showed that alleles carrying this mutation shared a common SNP haplotype.Conclusions:Our findings suggest the existence of a founder effect responsible for FHHNC in our cohort.Testing for the presence of mutation p.G20D should be the first genetic screening in Spanish patients.