{"id":4422505,"date":"2025-01-11T21:40:55","date_gmt":"2025-01-12T03:40:55","guid":{"rendered":"https:\/\/myendoconsult.com\/learn\/topics\/beta-cell-hyperplasia\/"},"modified":"2025-01-12T12:47:16","modified_gmt":"2025-01-12T18:47:16","slug":"beta-cell-hyperplasia","status":"publish","type":"oen_topic","link":"https:\/\/myendoconsult.com\/learn\/topics\/beta-cell-hyperplasia\/","title":{"rendered":"Beta Cell Hyperplasia"},"content":{"rendered":"\n<h2 class=\"wp-block-heading\">PRIMARY PANCREATIC \u03b2-CELL HYPERPLASIA<\/h2>\n\n\n\n<ul class=\"wp-block-list\">\n<li><strong>Definition<\/strong>\n<ul class=\"wp-block-list\">\n<li>A rare cause of hypoglycemia due to an overgrowth (hyperplasia) of the pancreatic \u03b2-cells.<\/li>\n\n\n\n<li>Can present as either <strong>focal<\/strong> or <strong>diffuse<\/strong> hyperplasia.<\/li>\n\n\n\n<li><strong>Nesidioblastosis<\/strong>: neoformation of islets of Langerhans from pancreatic duct epithelium; often accompanies \u03b2-cell hyperplasia.<\/li>\n<\/ul>\n<\/li>\n<\/ul>\n\n\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\"\/>\n\n\n\n<h2 class=\"wp-block-heading\">CONGENITAL HYPERINSULINISM<\/h2>\n\n\n\n<ul class=\"wp-block-list\">\n<li><strong>Epidemiology<\/strong>\n<ul class=\"wp-block-list\">\n<li>Occurs in \u223c1 in 50,000 live births.<\/li>\n\n\n\n<li>Inherited in an <strong>autosomal dominant<\/strong> or <strong>autosomal recessive<\/strong> pattern.<\/li>\n<\/ul>\n<\/li>\n\n\n\n<li><strong>Pathophysiology<\/strong>\n<ol class=\"wp-block-list\">\n<li><strong>Common Cause<\/strong>: Loss-of-function mutations in the <strong>K-ATP channel<\/strong> genes on \u03b2-cells\n<ul class=\"wp-block-list\">\n<li><strong>Key genes<\/strong>:\n<ul class=\"wp-block-list\">\n<li>Sulfonylurea receptor type 1 subunit (<strong>SUR1<\/strong>, coded by <strong>ABCC8<\/strong>)<\/li>\n\n\n\n<li>Potassium channel subunit (<strong>Kir6.2<\/strong>, coded by <strong>KCNJ11<\/strong>)<\/li>\n<\/ul>\n<\/li>\n\n\n\n<li>Channel closure \u2192 persistent membrane depolarization \u2192 insulin oversecretion despite hypoglycemia.<\/li>\n<\/ul>\n<\/li>\n\n\n\n<li><strong>Other Mutations<\/strong>: Activating variants in genes encoding <strong>glutamate dehydrogenase<\/strong> or <strong>glucokinase<\/strong>.<\/li>\n\n\n\n<li><strong>Focal vs. Diffuse<\/strong>\n<ul class=\"wp-block-list\">\n<li><strong>Focal<\/strong> adenomatous islet hyperplasia: involves biallelic inactivation (loss of maternal allele + paternal abnormal allele) \u2192 hyperplasia localized to one area.<\/li>\n\n\n\n<li><strong>Diffuse<\/strong> hyperplasia: entire pancreas involved.<\/li>\n<\/ul>\n<\/li>\n<\/ol>\n<\/li>\n<\/ul>\n\n\n\n<figure class=\"wp-block-image size-full\"><img loading=\"lazy\" decoding=\"async\" width=\"2400\" height=\"3075\" src=\"https:\/\/myendoconsult.com\/learn\/wp-content\/uploads\/regulation-of-glucose.png\" alt=\"\" class=\"wp-image-4422750\" srcset=\"https:\/\/myendoconsult.com\/learn\/wp-content\/uploads\/regulation-of-glucose.png 2400w, https:\/\/myendoconsult.com\/learn\/wp-content\/uploads\/regulation-of-glucose-234x300.png 234w, https:\/\/myendoconsult.com\/learn\/wp-content\/uploads\/regulation-of-glucose-768x984.png 768w, https:\/\/myendoconsult.com\/learn\/wp-content\/uploads\/regulation-of-glucose-1199x1536.png 1199w, https:\/\/myendoconsult.com\/learn\/wp-content\/uploads\/regulation-of-glucose-1598x2048.png 1598w\" sizes=\"auto, (max-width: 2400px) 100vw, 2400px\" \/><figcaption class=\"wp-element-caption\">Regulation of glucose by pancreatic hormones<\/figcaption><\/figure>\n\n\n\n<ul class=\"wp-block-list\">\n<li><strong>Clinical Presentation<\/strong>\n<ul class=\"wp-block-list\">\n<li><strong>Severe, intractable hypoglycemia<\/strong> in neonates\/infants.<\/li>\n\n\n\n<li>Neonatal signs:\n<ul class=\"wp-block-list\">\n<li>Altered consciousness<\/li>\n\n\n\n<li>Tremors<\/li>\n\n\n\n<li>Hypotonia<\/li>\n\n\n\n<li>Seizures<\/li>\n\n\n\n<li>Apnea<\/li>\n\n\n\n<li>Cyanotic spells<\/li>\n<\/ul>\n<\/li>\n\n\n\n<li><strong>Macrosomia<\/strong> common.<\/li>\n\n\n\n<li>Milder or partial defects can present later in childhood.<\/li>\n<\/ul>\n<\/li>\n\n\n\n<li><strong>Differential Diagnosis<\/strong> of Hypoglycemia in Infancy\/Childhood\n<ul class=\"wp-block-list\">\n<li><strong>Hyperinsulinism<\/strong>: congenital hyperinsulinism, nesidioblastosis, infant of a diabetic mother, maternal sulfonylureas.<\/li>\n\n\n\n<li><strong>Drug-related<\/strong>: exogenous insulin, sulfonylureas.<\/li>\n\n\n\n<li><strong>Severe illness<\/strong>: e.g., sepsis, renal\/hepatic failure.<\/li>\n\n\n\n<li><strong>Counterregulatory hormone deficiency<\/strong>: e.g., hypopituitarism, Addison disease.<\/li>\n\n\n\n<li><strong>Metabolic enzyme defects<\/strong>: glycogen <a href=\"https:\/\/myendoconsult.com\/learn\/topics\/storage-diseases\/\" data-wpil-monitor-id=\"317\">storage diseases<\/a>, fatty acid oxidation defects, organic acidemias.<\/li>\n<\/ul>\n<\/li>\n\n\n\n<li><strong>Treatment<\/strong>\n<ol class=\"wp-block-list\">\n<li><strong>Medical<\/strong>: Diazoxide (inhibits insulin release), octreotide (somatostatin analogue).<\/li>\n\n\n\n<li><strong>Surgical<\/strong>:\n<ul class=\"wp-block-list\">\n<li><strong>Focal<\/strong> lesion: resect focal hyperplastic area \u2192 potential cure.<\/li>\n\n\n\n<li><strong>Diffuse<\/strong> disease: more extensive pancreatectomy may be required.<\/li>\n<\/ul>\n<\/li>\n<\/ol>\n<\/li>\n<\/ul>\n\n\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\"\/>\n\n\n\n<h2 class=\"wp-block-heading\">NONINSULINOMA PANCREATOGENOUS HYPOGLYCEMIA SYNDROME (NIPHS)<\/h2>\n\n\n\n<ul class=\"wp-block-list\">\n<li><strong>Definition<\/strong>\n<ul class=\"wp-block-list\">\n<li>A form of islet \u03b2-cell hyperplasia that typically causes <strong>postprandial<\/strong> (rather than fasting) hypoglycemia.<\/li>\n\n\n\n<li>Also called \u201cnesidioblastosis\u201d in adults.<\/li>\n<\/ul>\n<\/li>\n\n\n\n<li><strong>Clinical Presentation<\/strong>\n<ul class=\"wp-block-list\">\n<li><strong>Postprandial hyperinsulinemic hypoglycemia<\/strong> and related adrenergic\/neuroglycopenic symptoms.<\/li>\n\n\n\n<li>Surgical partial pancreatectomy often cures the condition.<\/li>\n<\/ul>\n<\/li>\n\n\n\n<li><strong>Post\u2013Gastric Bypass Hypoglycemia<\/strong>\n<ul class=\"wp-block-list\">\n<li>Similar pathologic changes (\u03b2-cell hyperplasia, nesidioblastosis) seen after Roux-en-Y <a href=\"https:\/\/myendoconsult.com\/learn\/hypoglycemia-after-gastric-bypass\/\" data-wpil-monitor-id=\"318\">gastric bypass<\/a>.<\/li>\n\n\n\n<li>Onset: 6 months to 8 years postoperatively.<\/li>\n\n\n\n<li>Mechanisms may involve reduced ghrelin or other incompletely understood factors.<\/li>\n<\/ul>\n<\/li>\n<\/ul>\n\n\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\"\/>\n\n\n\n<h2 class=\"wp-block-heading\">EVALUATION AND DIAGNOSIS<\/h2>\n\n\n\n<ul class=\"wp-block-list\">\n<li><strong>Timing of Hypoglycemia<\/strong>\n<ul class=\"wp-block-list\">\n<li>\u03b2-cell hyperplasia typically \u2192 <strong>postprandial<\/strong> hypoglycemia (insulinoma usually \u2192 fasting hypoglycemia).<\/li>\n\n\n\n<li>Lab abnormalities (low glucose, inappropriately high insulin\/C-peptide\/proinsulin) resemble those in <strong>insulinoma<\/strong>.<\/li>\n<\/ul>\n<\/li>\n\n\n\n<li><strong>Imaging<\/strong>\n<ul class=\"wp-block-list\">\n<li>Often <strong>not helpful<\/strong> in localizing diffuse hyperplasia (unlike insulinoma, which is typically a discrete tumor).<\/li>\n<\/ul>\n<\/li>\n\n\n\n<li><strong>Selective Arterial Calcium Stimulation<\/strong> with Hepatic Venous Sampling\n<ol class=\"wp-block-list\">\n<li>Inject Ca\u00b2\u207a gluconate into branches of arterial supply to the pancreas (gastroduodenal, splenic, superior mesenteric).<\/li>\n\n\n\n<li>Measure insulin in timed hepatic venous samples.<\/li>\n\n\n\n<li><strong>Abnormal<\/strong>: \u22652\u20133\u00d7 increase in hepatic vein insulin from baseline.<\/li>\n\n\n\n<li>Helps <strong>regionalize<\/strong> dysfunctional \u03b2-cells \u2192 partial pancreatectomy guided by the arterial distribution with abnormal insulin response.<\/li>\n<\/ol>\n<\/li>\n<\/ul>\n","protected":false},"excerpt":{"rendered":"<p>PRIMARY PANCREATIC \u03b2-CELL HYPERPLASIA CONGENITAL HYPERINSULINISM NONINSULINOMA PANCREATOGENOUS HYPOGLYCEMIA SYNDROME (NIPHS) EVALUATION AND DIAGNOSIS<\/p>\n","protected":false},"featured_media":0,"template":"","oen_topic_chapter":[686],"class_list":["post-4422505","oen_topic","type-oen_topic","status-publish","hentry","oen_topic_chapter-the-pancreas","post-wrapper","thrv_wrapper"],"_links":{"self":[{"href":"https:\/\/myendoconsult.com\/learn\/wp-json\/wp\/v2\/oen_topic\/4422505","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/myendoconsult.com\/learn\/wp-json\/wp\/v2\/oen_topic"}],"about":[{"href":"https:\/\/myendoconsult.com\/learn\/wp-json\/wp\/v2\/types\/oen_topic"}],"version-history":[{"count":4,"href":"https:\/\/myendoconsult.com\/learn\/wp-json\/wp\/v2\/oen_topic\/4422505\/revisions"}],"predecessor-version":[{"id":4422752,"href":"https:\/\/myendoconsult.com\/learn\/wp-json\/wp\/v2\/oen_topic\/4422505\/revisions\/4422752"}],"wp:attachment":[{"href":"https:\/\/myendoconsult.com\/learn\/wp-json\/wp\/v2\/media?parent=4422505"}],"wp:term":[{"taxonomy":"oen_topic_chapter","embeddable":true,"href":"https:\/\/myendoconsult.com\/learn\/wp-json\/wp\/v2\/oen_topic_chapter?post=4422505"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}