Snapshot A 42-year-old male executive complains of upper abdominal pain. He says he is under considerable stress at work and smokes a pack of cigarettes daily. He has no history of shortness of breath, swelling of the feet, chest pain, or allergies. Further history reveals that the pain is worse at night and often wakens him from sleep. It occurs between meals and is subsided by drinking milk and avoiding spicy foods. On 1 occasion he vomited blood. Testing reveals serum gastrin level of 1000 pg/ml (normal < 300 pg/ml). Introduction Clinical definition syndrome characterized by the secretion of gastrin by duodenal or pancreatic neuroendocrine tumors (gastrinomas) Epidemiology demographics annual incidence is 0.5-2 per million high incidence in men compared to women only 25% of gastrinomas arise in the pancreas with the majority occurring in the duodenum Pathogenesis excessive gastrin secretion from gastrinoma leads to high gastric acid output gastrin has trophic action on gastric parietal cells and histamine-secreting enterochromaffin-like cells high gastric acid secreting overwhelms the neutralizing capacity of pancreatic bicarbonate secretion, resulting in low pH of intestinal contents the low pH inactivates pancreatic digestive enzymes and thus interferes with the emulsification of fat by bile acids results in maldigestion and malabsorption high serum gastrin concentrations inhibit the absorption of sodium and water by the small intestine Associated conditions multiple endocrine neoplasia type 1 (MEN1) Presentation Symptoms peptic ulcer disease heartburn weight loss diarrhea Physical exam abdominal tenderness Imaging Upper endoscopy Contrast-enhanced computed tomography (CT) or magnetic resonance imaging (MRI) Somatostatin receptor scintigraphy Endoscopic ultrasound usually indicated prior to surgical resection as it has greater sensitivity in detecting small tumors Studies Fasting serum gastrin concentration and gastric pH best initial test serum gastrin value > 10 times the upper limit of normal (> 1000 pg/mL) in the presence of gastric pH < 2 is diagnostic Secretin stimulation test indicated in patients with elevated gastrin/low gastrin pH that do not meet the diagnostic criteria differentiates gastrinomas from other causes of hypergastrinemia (e.g., antral G-cell hyperplasia) patients with gastrinomas will have a dramatic rise in serum gastrin following secretin stimulation (normal gastric G cells are inhibited by secretin) Calcium infusion study indicated in patients with strong clinical suspicion despite a negative secretin stimulation test MEN1 evaluation serum parathormone levels ionized calcium levels prolactin levels Differential Antral G-cell hyperplasia distinguishing factors poor response to secretin stimulation ltest absence of gastrinoma on imaging Treatment First-line medical management with proton pump inhibitors (e.g., omeprazole) and H2-receptor anatagonists (e.g., ranitidine) surgical resection eliminates need for antisecretory medical therapy and protects against the morbidity and mortality of metastasis Second-line octreotide (rarely required) reoperation indicated in patients with intractable symptoms who fails dietary and medical therapy Complications Stricture Perforation Metastatic gastrinoma liver is the most common site most common cause of morbidity and mortality
QUESTIONS 1 of 4 1 2 3 4 Previous Next Lab Values Blood Hematologic Cerebrospinal Sweat, Urine, and BMI Blood, Plasma, Serum Reference Range ALT 8-20 U/L Amylase, serum 25-125 U/L AST 8-20 U/L Bilirubin, serum (adult) Total // Direct 0.1-1.0 mg/dL // 0.0-0.3 mg/dL Calcium, serum (Ca2+) 8.4-10.2 mg/dL Cholesterol, serum Rec: < 200 mg/dL Cortisol, serum 0800 h: 5-23 μg/dL //1600 h: 3-15 μg/dL 2000 h: ≤ 50% of 0800 h Creatine kinase, serum Male: 25-90 U/LFemale: 10-70 U/L Creatinine, serum 0.6-1.2 mg/dL Electrolytes, serum Sodium (Na+) 136-145 mEq/L Chloride (Cl-) 95-105 mEq/L Potassium (K+) 3.5-5.0 mEq/L Bicarbonate (HCO3-) 22-28 mEq/L Magnesium (Mg2+) 1.5-2.0 mEq/L Estriol, total, serum (in pregnancy) 24-28 wks // 32-36 wks 30-170 ng/mL // 60-280 ng/mL 28-32 wk // 36-40 wks 40-220 ng/mL // 80-350 ng/mL Ferritin, serum Male: 15-200 ng/mLFemale: 12-150 ng/mL Follicle-stimulating hormone, serum/plasma Male: 4-25 mIU/mL Female: premenopause: 4-30 mIU/mL midcycle peak: 10-90 mIU/mL postmenopause: 40-250 pH 7.35-7.45 PCO2 33-45 mmHg PO2 75-105 mmHg Glucose, serum Fasting: 70-110 mg/dL2-h postprandial:<120 mg/dL Growth hormone - arginine stimulation Fasting: <5 ng/mLProvocative stimuli: > 7ng/mL Immunoglobulins, serum IgA 76-390 mg/dL IgE 0-380 IU/mL IgG 650-1500 mg/dL IgM 40-345 mg/dL Iron 50-170 μg/dL Lactate dehydrogenase, serum 45-90 U/L Luteinizing hormone, serum/plasma Male: 6-23 mIU/mL Female: follicular phase: 5-30 mIU/mL midcycle: 75-150 mIU/mL postmenopause 30-200 mIU/mL Osmolality, serum 275-295 mOsmol/kd H2O Parathyroid hormone, serume, N-terminal 230-630 pg/mL Phosphatase (alkaline), serum (p-NPP at 30° C) 20-70 U/L Phosphorus (inorganic), serum 3.0-4.5 mg/dL Prolactin, serum (hPRL) < 20 ng/mL Proteins, serum Total (recumbent) 6.0-7.8 g/dL Albumin 3.5-5.5 g/dL Globulin 2.3-3.5 g/dL Thyroid-stimulating hormone, serum or plasma .5-5.0 μU/mL Thyroidal iodine (123I) uptake 8%-30% of administered dose/24h Thyroxine (T4), serum 5-12 μg/dL Triglycerides, serum 35-160 mg/dL Triiodothyronine (T3), serum (RIA) 115-190 ng/dL Triiodothyronine (T3) resin uptake 25%-35% Urea nitrogen, serum 7-18 mg/dL Uric acid, serum 3.0-8.2 mg/dL Hematologic Reference Range Bleeding time 2-7 minutes Erythrocyte count Male: 4.3-5.9 million/mm3Female: 3.5-5.5 million mm3 Erythrocyte sedimentation rate (Westergren) Male: 0-15 mm/hFemale: 0-20 mm/h Hematocrit Male: 41%-53%Female: 36%-46% Hemoglobin A1c ≤ 6 % Hemoglobin, blood Male: 13.5-17.5 g/dLFemale: 12.0-16.0 g/dL Hemoglobin, plasma 1-4 mg/dL Leukocyte count and differential Leukocyte count 4,500-11,000/mm3 Segmented neutrophils 54%-62% Bands 3%-5% Eosinophils 1%-3% Basophils 0%-0.75% Lymphocytes 25%-33% Monocytes 3%-7% Mean corpuscular hemoglobin 25.4-34.6 pg/cell Mean corpuscular hemoglobin concentration 31%-36% Hb/cell Mean corpuscular volume 80-100 μm3 Partial thromboplastin time (activated) 25-40 seconds Platelet count 150,000-400,000/mm3 Prothrombin time 11-15 seconds Reticulocyte count 0.5%-1.5% of red cells Thrombin time < 2 seconds deviation from control Volume Plasma Male: 25-43 mL/kgFemale: 28-45 mL/kg Red cell Male: 20-36 mL/kgFemale: 19-31 mL/kg Cerebrospinal Fluid Reference Range Cell count 0-5/mm3 Chloride 118-132 mEq/L Gamma globulin 3%-12% total proteins Glucose 40-70 mg/dL Pressure 70-180 mm H2O Proteins, total < 40 mg/dL Sweat Reference Range Chloride 0-35 mmol/L Urine Calcium 100-300 mg/24 h Chloride Varies with intake Creatinine clearance Male: 97-137 mL/minFemale: 88-128 mL/min Estriol, total (in pregnancy) 30 wks 6-18 mg/24 h 35 wks 9-28 mg/24 h 40 wks 13-42 mg/24 h 17-Hydroxycorticosteroids Male: 3.0-10.0 mg/24 hFemale: 2.0-8.0 mg/24 h 17-Ketosteroids, total Male: 8-20 mg/24 hFemale: 6-15 mg/24 h Osmolality 50-1400 mOsmol/kg H2O Oxalate 8-40 μg/mL Potassium Varies with diet Proteins, total < 150 mg/24 h Sodium Varies with diet Uric acid Varies with diet Body Mass Index (BMI) Adult: 19-25 kg/m2 Calculator ( ) xy AC 7 8 9 ÷ 4 5 6 × 1 2 3 - 0 . = + Sorry, this question is for PEAK Premium Subscribers only Upgrade to PEAK You have 100% on this question. Just skip this one for now. Take This Question Anyway (M1.GI.25) A 41-year-old female complains of frequent diarrhea and abdominal pain between meals. Endoscopy reveals a duodenal ulcer distal to the duodenal bulb. CT scan of the abdomen demonstrates a pancreatic mass, and subsequent tissue biopsy of the pancreas reveals a malignant islet cell tumor. Which of the following hormones is likely to be markedly elevated in this patient: Review Topic | Tested Concept QID: 101082 Type & Select Correct Answer 1 Gastrin 59% (27/46) 2 Cholecystokinin 4% (2/46) 3 Secretin 9% (4/46) 4 Vasoactive intestinal peptide 22% (10/46) 5 Motilin 0% (0/46) M1 Question Complexity B Question Importance Select Answer to see Preferred Response SUBMIT RESPONSE 1 You have 100% on this question. Just skip this one for now. Take This Question Anyway (M1.GI.174) A 45-year-old male patient with a history of recurrent nephrolithiasis and chronic lower back pain presents to the ER with severe, sudden-onset, upper abdominal pain. The patient is febrile, hypotensive, and tachycardic, and is rushed to the OR for exploratory laporotomy. Surgery reveals that the patient has a perforated gastric ulcer. Despite appropriate therapy, the patient expires, and subsequent autopsy reveals multiple ulcers in the stomach, duodenum, and jejunum. The patient had been complaining of abdominal pain and diarrhea for several months but had only been taking ibuprofen for his lower back pain for the past 3 weeks. What is the most likely cause of the patient's presentation? Review Topic | Tested Concept QID: 101231 Type & Select Correct Answer 1 A gastrin-secreting tumor of the pancreas 67% (29/43) 2 A vasoactive-intestinal-peptide (VIP) secreting tumor of the pancreas 5% (2/43) 3 Cytomegalovirus infection 0% (0/43) 4 H. pylori infection 12% (5/43) 5 Chronic NSAID use 16% (7/43) M1 Question Complexity A Question Importance Select Answer to see Preferred Response SUBMIT RESPONSE 1 Sorry, this question is for PEAK Premium Subscribers only Upgrade to PEAK