{"id":111919,"date":"2025-06-16T12:12:37","date_gmt":"2025-06-16T03:12:37","guid":{"rendered":"https:\/\/www.hiro-clinic.or.jp\/nipt\/bartter-syndrome-bsnd-type4a\/"},"modified":"2025-08-22T15:17:57","modified_gmt":"2025-08-22T06:17:57","slug":"bartter-syndrome-bsnd-type4a","status":"publish","type":"post","link":"https:\/\/www.hiro-clinic.or.jp\/nipt\/bartter-syndrome-bsnd-type4a\/?lang=en","title":{"rendered":"Overview of Bartter Syndrome Type IVa"},"content":{"rendered":"\n<div style=\"height:20px\" aria-hidden=\"true\" class=\"wp-block-spacer\"><\/div>\n\n\n\n<div style=\"border: 4px solid #e9e4f5; background-color: #fcfbff; border-radius: 12px; padding: 1.5rem; margin: 1.5rem 0 2.5rem; font-family: 'Helvetica Neue', sans-serif; line-height: 1.6; box-shadow: 0 2px 8px rgba(0, 0, 0, 0.03);\">\n  <div id=\"ez-toc-container\" class=\"ez-toc-v2_0_84 counter-hierarchy ez-toc-counter ez-toc-grey ez-toc-container-direction\">\n<div class=\"ez-toc-title-container\">\n<p class=\"ez-toc-title\" style=\"cursor:inherit\">\u76ee\u6b21<\/p>\n<span class=\"ez-toc-title-toggle\"><a href=\"#\" class=\"ez-toc-pull-right ez-toc-btn ez-toc-btn-xs ez-toc-btn-default ez-toc-toggle\" aria-label=\"Toggle Table of Content\"><span class=\"ez-toc-js-icon-con\"><span class=\"\"><span class=\"eztoc-hide\" style=\"display:none;\">Toggle<\/span><span class=\"ez-toc-icon-toggle-span\"><svg style=\"fill: #999;color:#999\" xmlns=\"http:\/\/www.w3.org\/2000\/svg\" class=\"list-377408\" width=\"20px\" height=\"20px\" viewBox=\"0 0 24 24\" fill=\"none\"><path d=\"M6 6H4v2h2V6zm14 0H8v2h12V6zM4 11h2v2H4v-2zm16 0H8v2h12v-2zM4 16h2v2H4v-2zm16 0H8v2h12v-2z\" fill=\"currentColor\"><\/path><\/svg><svg style=\"fill: #999;color:#999\" class=\"arrow-unsorted-368013\" xmlns=\"http:\/\/www.w3.org\/2000\/svg\" width=\"10px\" height=\"10px\" viewBox=\"0 0 24 24\" version=\"1.2\" baseProfile=\"tiny\"><path d=\"M18.2 9.3l-6.2-6.3-6.2 6.3c-.2.2-.3.4-.3.7s.1.5.3.7c.2.2.4.3.7.3h11c.3 0 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href=\"https:\/\/www.hiro-clinic.or.jp\/nipt\/bartter-syndrome-bsnd-type4a\/?lang=en\/#Overview_of_Bartter_Syndrome_Type_IVa\" >Overview of Bartter Syndrome Type IVa<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-4\" href=\"https:\/\/www.hiro-clinic.or.jp\/nipt\/bartter-syndrome-bsnd-type4a\/?lang=en\/#Genetic_and_Molecular_Basis\" >Genetic and Molecular Basis<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-5\" href=\"https:\/\/www.hiro-clinic.or.jp\/nipt\/bartter-syndrome-bsnd-type4a\/?lang=en\/#Epidemiology\" >Epidemiology<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-6\" href=\"https:\/\/www.hiro-clinic.or.jp\/nipt\/bartter-syndrome-bsnd-type4a\/?lang=en\/#Etiology\" >Etiology<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-7\" href=\"https:\/\/www.hiro-clinic.or.jp\/nipt\/bartter-syndrome-bsnd-type4a\/?lang=en\/#Clinical_Presentation\" >Clinical Presentation<\/a><ul class='ez-toc-list-level-3' ><li class='ez-toc-heading-level-3'><a class=\"ez-toc-link ez-toc-heading-8\" href=\"https:\/\/www.hiro-clinic.or.jp\/nipt\/bartter-syndrome-bsnd-type4a\/?lang=en\/#Symptoms_in_Pregnancy_and_the_Newborn_Period\" >Symptoms in Pregnancy and the Newborn Period<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-3'><a class=\"ez-toc-link ez-toc-heading-9\" href=\"https:\/\/www.hiro-clinic.or.jp\/nipt\/bartter-syndrome-bsnd-type4a\/?lang=en\/#Symptoms_in_Infancy_and_Childhood\" >Symptoms in Infancy and Childhood<\/a><\/li><\/ul><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-10\" href=\"https:\/\/www.hiro-clinic.or.jp\/nipt\/bartter-syndrome-bsnd-type4a\/?lang=en\/#Diagnostic_Evaluation\" >Diagnostic Evaluation<\/a><ul class='ez-toc-list-level-3' ><li class='ez-toc-heading-level-3'><a class=\"ez-toc-link ez-toc-heading-11\" href=\"https:\/\/www.hiro-clinic.or.jp\/nipt\/bartter-syndrome-bsnd-type4a\/?lang=en\/#Blood_and_Urine_Testing\" >Blood and Urine Testing<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-3'><a class=\"ez-toc-link ez-toc-heading-12\" href=\"https:\/\/www.hiro-clinic.or.jp\/nipt\/bartter-syndrome-bsnd-type4a\/?lang=en\/#Hearing_Assessment\" >Hearing Assessment<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-3'><a class=\"ez-toc-link ez-toc-heading-13\" href=\"https:\/\/www.hiro-clinic.or.jp\/nipt\/bartter-syndrome-bsnd-type4a\/?lang=en\/#Genetic_Testing\" >Genetic Testing<\/a><\/li><\/ul><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-14\" href=\"https:\/\/www.hiro-clinic.or.jp\/nipt\/bartter-syndrome-bsnd-type4a\/?lang=en\/#Management_and_Treatment\" >Management and Treatment<\/a><ul class='ez-toc-list-level-3' ><li class='ez-toc-heading-level-3'><a class=\"ez-toc-link ez-toc-heading-15\" href=\"https:\/\/www.hiro-clinic.or.jp\/nipt\/bartter-syndrome-bsnd-type4a\/?lang=en\/#Management_During_Pregnancy\" >Management During Pregnancy<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-3'><a class=\"ez-toc-link ez-toc-heading-16\" href=\"https:\/\/www.hiro-clinic.or.jp\/nipt\/bartter-syndrome-bsnd-type4a\/?lang=en\/#Postnatal_and_Long-Term_Management\" >Postnatal and Long-Term Management<\/a><\/li><\/ul><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-17\" href=\"https:\/\/www.hiro-clinic.or.jp\/nipt\/bartter-syndrome-bsnd-type4a\/?lang=en\/#Prognosis\" >Prognosis<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-18\" href=\"https:\/\/www.hiro-clinic.or.jp\/nipt\/bartter-syndrome-bsnd-type4a\/?lang=en\/#Key_Scientific_Terms\" >Key Scientific Terms<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-19\" href=\"https:\/\/www.hiro-clinic.or.jp\/nipt\/bartter-syndrome-bsnd-type4a\/?lang=en\/#References\" >References<\/a><\/li><\/ul><\/nav><\/div>\n<h2 style=\"margin-top: 0; margin-bottom: 0.75rem; font-size: 1.25rem; color: #7e6cae; text-align: left; border: none; border-bottom: none; padding-bottom: 0; display: block;\"><span class=\"ez-toc-section\" id=\"%E3%82%84%E3%81%95%E3%81%97%E3%81%84%E3%81%BE%E3%81%A8%E3%82%81\"><\/span>\u3084\u3055\u3057\u3044\u307e\u3068\u3081<span class=\"ez-toc-section-end\"><\/span><\/h2>\n  <p style=\"margin: 0; font-size: 1rem; color: #444;\">\n   This article offers a clear, evidence-based overview of Bartter Syndrome Type IVa, a rare kidney disorder that also causes sensorineural hearing loss. It explains how BSND gene mutations disrupt kidney salt handling and auditory function, outlines symptoms from pregnancy through childhood, and details diagnostic tests, treatment strategies, and prognosis. It is especially useful for families, clinicians, and anyone seeking a scientifically accurate resource on this complex condition.\n\n  <\/p>\n<\/div>\n\n\n\n<h2 class=\"wp-block-heading\"><span class=\"ez-toc-section\" id=\"%E9%81%BA%E4%BC%9D%E5%AD%90%E9%A0%98%E5%9F%9F_Implicated_Genomic_Region\"><\/span>\u907a\u4f1d\u5b50\u9818\u57df | Implicated Genomic Region<span class=\"ez-toc-section-end\"><\/span><\/h2>\n\n\n\n<div style=\"height:18px\" aria-hidden=\"true\" class=\"wp-block-spacer\"><\/div>\n\n\n\n<p class=\"has-text-align-center\"><strong>BSND<\/strong><\/p>\n\n\n<div class=\"wp-block-image\">\n<figure class=\"aligncenter size-large\"><img decoding=\"async\" width=\"1024\" height=\"26\" src=\"\/nipt\/wp-content\/uploads\/2025\/06\/BSND-hgtIdeo_genome_asia_278e1_f81e60-1024x26.png\" alt=\"BSND\" class=\"wp-image-101397\"\/><\/figure><\/div>\n\n\n<div style=\"height:18px\" aria-hidden=\"true\" class=\"wp-block-spacer\"><\/div>\n\n\n\n<h2 class=\"wp-block-heading\"><span class=\"ez-toc-section\" id=\"Overview_of_Bartter_Syndrome_Type_IVa\"><\/span><strong>Overview of Bartter Syndrome Type IVa<\/strong><span class=\"ez-toc-section-end\"><\/span><\/h2>\n\n\n\n<p>Bartter syndrome is a rare inherited disorder that affects how the kidneys regulate salt and electrolyte balance. Among its subtypes, Type IVa is one of the more severe forms, caused by mutations in the <strong>BSND gene<\/strong>. These mutations interfere with the normal functioning of kidney ion channels and also affect the inner ear, leading to a combination of kidney dysfunction and <strong>sensorineural hearing loss<\/strong>. This subtype, sometimes referred to as <strong>infantile Bartter syndrome with sensorineural deafness<\/strong> or <strong>DFNB73<\/strong>, often becomes apparent in the womb or shortly after birth.<\/p>\n\n\n\n<p>Children with this condition commonly present with dehydration, poor growth, and significant electrolyte disturbances, along with bilateral hearing loss that persists throughout life. Understanding the genetic, clinical, and biochemical basis of this syndrome is crucial for accurate diagnosis and management.<\/p>\n\n\n\n<h2 class=\"wp-block-heading\"><span class=\"ez-toc-section\" id=\"Genetic_and_Molecular_Basis\"><\/span><strong>Genetic and Molecular Basis<\/strong><span class=\"ez-toc-section-end\"><\/span><\/h2>\n\n\n\n<p>The <strong>BSND gene<\/strong> is located on the short arm of chromosome 1 (region 1p32.3) and encodes a protein known as <strong>Barttin<\/strong>. This protein plays a critical role in supporting the function of two chloride channels, <strong>ClC-Ka<\/strong> and <strong>ClC-Kb<\/strong>, encoded by the genes <strong>CLCNKA<\/strong> and <strong>CLCNKB<\/strong> respectively. These chloride channels are found in specific tissues where electrolyte handling is vital: the thick ascending limb of the loop of Henle in the kidneys and the inner ear.<\/p>\n\n\n\n<p>When the BSND gene carries mutations, the production or function of Barttin is disrupted. Without properly functioning Barttin, the chloride channels cannot assemble or operate as needed. In the kidneys, this leads to significant salt and fluid losses, while in the inner ear, it disrupts the potassium circulation needed to generate the <strong>endolymphatic potential<\/strong>, which is essential for hearing. This dual disruption explains why patients present with both renal abnormalities and sensorineural hearing loss.<\/p>\n\n\n\n<h2 class=\"wp-block-heading\"><span class=\"ez-toc-section\" id=\"Epidemiology\"><\/span><strong>Epidemiology<\/strong><span class=\"ez-toc-section-end\"><\/span><\/h2>\n\n\n\n<p>Bartter syndrome is extremely rare, with an estimated frequency of about <strong>1 in 100,000 live births<\/strong>. Type IVa is rarer still. Certain regions such as <strong>Costa Rica<\/strong> and <strong>Kuwait<\/strong> report higher numbers of cases, often linked to <strong>consanguinity<\/strong>, where parents are related by blood. In such populations, autosomal recessive conditions like this one are more common, since both parents are more likely to carry the same pathogenic gene variant.<\/p>\n\n\n\n<h2 class=\"wp-block-heading\"><span class=\"ez-toc-section\" id=\"Etiology\"><\/span><strong>Etiology<\/strong><span class=\"ez-toc-section-end\"><\/span><\/h2>\n\n\n\n<p>The condition follows an <strong>autosomal recessive inheritance pattern<\/strong>, meaning that a child must inherit two defective copies of the BSND gene, one from each parent, to develop the disorder. When Barttin is absent or malfunctioning, the chloride channels in both the kidneys and inner ear are compromised. The kidneys lose the ability to reclaim sodium and chloride efficiently, resulting in excessive urinary losses and electrolyte imbalance. At the same time, the inner ear cannot maintain the ionic gradient required for normal auditory function, leading to congenital bilateral sensorineural hearing loss.<\/p>\n\n\n\n<h2 class=\"wp-block-heading\"><span class=\"ez-toc-section\" id=\"Clinical_Presentation\"><\/span><strong>Clinical Presentation<\/strong><span class=\"ez-toc-section-end\"><\/span><\/h2>\n\n\n\n<h3 class=\"wp-block-heading\"><span class=\"ez-toc-section\" id=\"Symptoms_in_Pregnancy_and_the_Newborn_Period\"><\/span><strong>Symptoms in Pregnancy and the Newborn Period<\/strong><span class=\"ez-toc-section-end\"><\/span><\/h3>\n\n\n\n<p>The earliest signs often develop during pregnancy. Around <strong>22 to 28 weeks of gestation<\/strong>, the fetus begins producing unusually large amounts of urine, which leads to <strong>polyhydramnios<\/strong>, or excessive amniotic fluid. This excess fluid increases uterine pressure, raising the risk of <strong>premature birth<\/strong>. Babies are often born with <strong>low birth weight<\/strong> and present shortly after birth with <strong>dehydration<\/strong> and difficulties in gaining weight due to ongoing salt and fluid losses. Severe <strong>polyuria<\/strong>, or high urine output, is common, as are <strong>electrolyte imbalances<\/strong>, particularly low levels of potassium and chloride. In nearly all cases, <strong>bilateral sensorineural hearing loss<\/strong> is present at birth, though the severity can vary.<\/p>\n\n\n\n<h3 class=\"wp-block-heading\"><span class=\"ez-toc-section\" id=\"Symptoms_in_Infancy_and_Childhood\"><\/span><strong>Symptoms in Infancy and Childhood<\/strong><span class=\"ez-toc-section-end\"><\/span><\/h3>\n\n\n\n<p>As children grow, additional complications become evident. Persistent <strong>hypokalemia<\/strong> can lead to muscle weakness, cramping, and occasional nausea. Many children crave salt and may develop <strong>constipation<\/strong> due to electrolyte imbalance. Growth is often delayed, and children may remain shorter than their peers or experience delayed puberty. Low muscle tone and delayed motor milestones are also frequently observed. Over time, children may develop subtle but characteristic facial features, such as a pointed chin, downturned corners of the mouth, and relatively prominent ears.<\/p>\n\n\n\n<h2 class=\"wp-block-heading\"><span class=\"ez-toc-section\" id=\"Diagnostic_Evaluation\"><\/span><strong>Diagnostic Evaluation<\/strong><span class=\"ez-toc-section-end\"><\/span><\/h2>\n\n\n\n<h3 class=\"wp-block-heading\"><span class=\"ez-toc-section\" id=\"Blood_and_Urine_Testing\"><\/span><strong>Blood and Urine Testing<\/strong><span class=\"ez-toc-section-end\"><\/span><\/h3>\n\n\n\n<p>The diagnostic process often begins with biochemical testing. Blood tests typically reveal <strong>hypokalemia<\/strong> (potassium levels below 3 mmol\/L), <strong>hypochloremia<\/strong> (low chloride levels), and <strong>metabolic alkalosis<\/strong>, where blood becomes abnormally alkaline. Hormone testing usually shows elevated <strong>renin<\/strong> and <strong>aldosterone<\/strong>, reflecting the body\u2019s attempt to compensate for salt losses. Urinary analysis often detects excessive excretion of sodium and calcium, reinforcing the diagnosis of a salt-wasting renal disorder.<\/p>\n\n\n\n<h3 class=\"wp-block-heading\"><span class=\"ez-toc-section\" id=\"Hearing_Assessment\"><\/span><strong>Hearing Assessment<\/strong><span class=\"ez-toc-section-end\"><\/span><\/h3>\n\n\n\n<p>Audiological testing is crucial. <strong>Otoacoustic emissions (OAE)<\/strong> testing usually shows no measurable response, indicating dysfunction of the cochlear hair cells. More detailed evaluations, such as <strong>brainstem evoked response audiometry (BERA)<\/strong> and <strong>auditory steady-state response (ASSR)<\/strong>, help to quantify the degree of hearing loss and confirm the absence of normal auditory pathway signaling.<\/p>\n\n\n\n<h3 class=\"wp-block-heading\"><span class=\"ez-toc-section\" id=\"Genetic_Testing\"><\/span><strong>Genetic Testing<\/strong><span class=\"ez-toc-section-end\"><\/span><\/h3>\n\n\n\n<p>Definitive diagnosis is made through genetic testing, typically via a panel that includes the <strong>BSND gene<\/strong>. In some cases, testing of the <strong>CLCNKB<\/strong> and <strong>SLC12A1<\/strong> genes is recommended to rule out other genetic subtypes of Bartter syndrome. For families with a known mutation, <strong>prenatal genetic testing<\/strong> through procedures such as <strong>amniocentesis<\/strong> can confirm whether the fetus is affected.<\/p>\n\n\n\n<h2 class=\"wp-block-heading\"><span class=\"ez-toc-section\" id=\"Management_and_Treatment\"><\/span><strong>Management and Treatment<\/strong><span class=\"ez-toc-section-end\"><\/span><\/h2>\n\n\n\n<h3 class=\"wp-block-heading\"><span class=\"ez-toc-section\" id=\"Management_During_Pregnancy\"><\/span><strong>Management During Pregnancy<\/strong><span class=\"ez-toc-section-end\"><\/span><\/h3>\n\n\n\n<p>When polyhydramnios is detected, close monitoring is essential. In some cases, drugs such as <strong>indomethacin<\/strong> may be administered to reduce fetal urine production, though this requires careful oversight due to potential effects on the fetal cardiovascular system.<\/p>\n\n\n\n<h3 class=\"wp-block-heading\"><span class=\"ez-toc-section\" id=\"Postnatal_and_Long-Term_Management\"><\/span><strong>Postnatal and Long-Term Management<\/strong><span class=\"ez-toc-section-end\"><\/span><\/h3>\n\n\n\n<p>Treatment after birth focuses on correcting and maintaining electrolyte balance. Oral supplementation of <strong>sodium chloride<\/strong> (5\u201310 mEq\/kg\/day) and <strong>potassium chloride<\/strong> (2\u20135 mEq\/kg\/day) is the mainstay of therapy. Nonsteroidal anti-inflammatory drugs (NSAIDs), such as <strong>indomethacin<\/strong> or <strong>ibuprofen<\/strong>, may be prescribed to reduce renal salt loss, while <strong>potassium-sparing diuretics<\/strong> like spironolactone or amiloride help to minimize potassium depletion.<\/p>\n\n\n\n<p>For hearing loss, early intervention is key. Many children benefit from <strong>hearing aids<\/strong>, while others may require <strong>cochlear implants<\/strong> depending on the severity of impairment. <a href=\"https:\/\/www.hiro-clinic.or.jp\/nipt\/early-nipt-august-only\/\">Early<\/a> speech and occupational therapy support better language acquisition and cognitive development. In children with persistent short stature despite good metabolic control, <strong>growth hormone therapy<\/strong> may be considered under specialist supervision.<\/p>\n\n\n\n<h2 class=\"wp-block-heading\"><span class=\"ez-toc-section\" id=\"Prognosis\"><\/span><strong>Prognosis<\/strong><span class=\"ez-toc-section-end\"><\/span><\/h2>\n\n\n\n<p>Hearing loss associated with Type IVa Bartter syndrome is <strong>irreversible<\/strong>, but early audiological support and consistent therapy significantly improve communication outcomes and quality of life. Kidney function varies among patients; while many maintain relatively stable renal health with good management, there is a recognized risk of progression to <strong>chronic kidney disease (CKD)<\/strong>, particularly in more severe cases.<\/p>\n\n\n\n<p>Growth and developmental outcomes also depend on early intervention. Many children grow into adulthood with near-normal height if treatment is optimized, though around 40% continue to experience some degree of short stature. With proper monitoring, adherence to therapy, and coordinated multidisciplinary care, most individuals with Type IVa Bartter syndrome can expect a <strong>normal life expectancy<\/strong> and a good quality of life.<\/p>\n\n\n\n<h2 class=\"wp-block-heading\"><span class=\"ez-toc-section\" id=\"Key_Scientific_Terms\"><\/span><strong>Key Scientific Terms<\/strong><span class=\"ez-toc-section-end\"><\/span><\/h2>\n\n\n\n<p>A <strong>gene<\/strong> is a segment of DNA that carries the instructions for producing proteins that shape traits and biological functions. A <strong>gene mutation<\/strong> is a change in this DNA sequence that can disrupt the gene\u2019s normal function and sometimes lead to disease. <strong>Autosomal recessive inheritance<\/strong> occurs when a child inherits a defective copy of a gene from both parents, resulting in the clinical manifestation of the condition.<\/p>\n\n\n\n<p>The <strong>BSND gene<\/strong> specifically encodes Barttin, a protein that supports the function of kidney and ear chloride channels. These channels are vital for maintaining fluid and electrolyte balance in the kidneys and for preserving the ionic environment necessary for hearing in the inner ear. The <strong>thick ascending limb of the loop of Henle<\/strong> is a segment of the kidney nephron that plays a major role in reabsorbing salt and maintaining overall fluid balance. <strong>Salt-wasting tubulopathy<\/strong> refers to a group of disorders, including Bartter syndrome, where the kidneys fail to retain salts effectively.<\/p>\n\n\n\n<p><strong>Sensorineural hearing loss<\/strong> refers to hearing impairment caused by damage to the inner ear or auditory nerve pathways. <strong>Polyhydramnios<\/strong> describes excessive amniotic fluid accumulation during pregnancy and is often a sign of fetal kidney dysfunction. <strong>Growth hormone therapy<\/strong> is sometimes used in children with persistent growth failure to help them achieve improved height and developmental outcomes.<\/p>\n\n\n\n<h2 class=\"wp-block-heading\"><span class=\"ez-toc-section\" id=\"References\"><\/span><strong>References<\/strong><span class=\"ez-toc-section-end\"><\/span><\/h2>\n\n\n\n<p>Florea L, et al. Genetic Heterogeneity in Bartter Syndrome: Clinical and Practical Importance. <em>Frontiers in Pediatrics<\/em>. 2022.<a href=\"https:\/\/doi.org\/10.3389\/fped.2022.908655\"> https:\/\/doi.org\/10.3389\/fped.2022.908655<\/a><\/p>\n\n\n\n<p>Zizlavsky S, et al. Sensorineural Hearing Loss in Bartter Syndrome. <em>Oto Rhino Laryngologica Indonesiana<\/em>. 2021.<a href=\"https:\/\/doi.org\/10.32637\/orli.v51i1.445\"> https:\/\/doi.org\/10.32637\/orli.v51i1.445<\/a><\/p>\n\n\n\n<!-- \u3042\u3044\u3046\u3048\u304a\u304b\u304d\u304f\u3051\u3053\u3055\u3057\u3059\u305b\u305d\u305f\u3061\u3064\u3066\u3068-->\n\n<script type=\"application\/ld+json\">\n{\n  \"@context\": \"https:\/\/schema.org\",\n  \"@graph\": [\n    {\n      \"@type\": \"WebPage\",\n      \"@id\": \"https:\/\/www.hiro-clinic.or.jp\/nipt\/bartter-syndrome-bsnd-type4a\",\n      \"url\": \"https:\/\/www.hiro-clinic.or.jp\/nipt\/bartter-syndrome-bsnd-type4a\",\n      \"name\": \"Bartter\u75c7\u5019\u7fa4\uff08BSND\u95a2\u9023\uff09\u306e\u75c7\u72b6\u3068\u6cbb\u7642\uff5c\u30d2\u30ed\u30af\u30ea\u30cb\u30c3\u30af\",\n      \"inLanguage\": \"ja\",\n      \"description\": 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