2.9 Hypoglycemia, Endocrine Tumors, Polyglandular Syndromes & Severe Hypertriglyceridemia

ABIM Internal Medicine Exam

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1 Chapter 0: The ABIM Exam, Blueprint & Study Strategy

0.1 Exam Format, Question Types & the 2026 Blueprint 0.2 Eligibility, Registration, Fees & Exam-Day Logistics 0.3 Scoring, the Passing Standard & Score Reports 0.4 Building a Blueprint-Weighted Study Plan

2 Chapter 1: Cardiovascular Disease (14% of Exam)

1.1 Ischemic Heart Disease & Acute Coronary Syndromes 1.2 Antithrombotic Therapy, Secondary Prevention & Mechanical Complications of MI 1.3 Atrial Fibrillation, Atrial Flutter & Stroke Prevention 1.4 Supraventricular Tachycardias, Ventricular Arrhythmias & Bradycardias 1.5 Heart Failure: Classification, Staging & Guideline-Directed Medical Therapy 1.6 Device Therapy, HFpEF & the Cardiomyopathies 1.7 Valvular Heart Disease & Endocarditis Prophylaxis 1.8 Pericardial Disease & Acute Aortic Syndromes 1.9 Hypertension: Classification, Diagnosis & Secondary Causes 1.10 Hypertensive Crises & Dyslipidemia 1.11 Adult Congenital Heart Disease & Coarctation of the Aorta 1.12 Syncope: Reflex, Orthostatic & Cardiac Causes 1.13 Cardiac Physical Examination, Murmurs & Antithrombotic Selection

3 Chapter 2: Endocrinology, Diabetes & Metabolism (9% of Exam)

2.1 Diabetes Mellitus: Diagnosis, Glycemic Targets & Pharmacotherapy 2.2 Insulin Therapy, Hyperglycemic Emergencies & Chronic Complications 2.3 Thyroid Function Testing & Hypothyroidism 2.4 Thyrotoxicosis, Thyroid Storm & Thyroid Nodules 2.5 Adrenal & Pituitary Disorders 2.6 Hypercalcemia, Hypocalcemia & Disorders of Mineral Metabolism 2.7 Osteoporosis & Paget Disease of Bone 2.8 Ovarian, Testicular & Reproductive Endocrine Disorders 2.9 Hypoglycemia, Endocrine Tumors, Polyglandular Syndromes & Severe Hypertriglyceridemia

4 Chapter 3: Gastroenterology & Hepatology (9% of Exam)

3.1 Esophageal Disease 3.2 Stomach & Duodenal Disease and Gastrointestinal Hemorrhage 3.3 Inflammatory Bowel Disease 3.4 Celiac Disease & Irritable Bowel Syndrome 3.5 Diverticular Disease & Colorectal Cancer Screening 3.6 Viral Hepatitis, Steatotic & Alcohol-Associated Liver Disease 3.7 Cirrhosis & the Complications of Portal Hypertension 3.8 Acute Pancreatitis 3.9 Chronic Pancreatitis & Biliary Tract Disease 3.10 Inherited, Autoimmune & Drug-Induced Liver Disease 3.11 Small Intestinal Disease, Ischemia & Gastrointestinal Complications of HIV

5 Chapter 4: Infectious Disease (9% of Exam)

4.1 Lower Respiratory Tract Infections & Sepsis Syndromes 4.2 Viral Respiratory Pathogens & Tuberculosis 4.3 Central Nervous System Infections 4.4 Skin, Soft Tissue, Bone & Joint Infections 4.5 Infective Endocarditis & Cardiovascular Infection 4.6 Clostridioides difficile & Catheter-Related Bloodstream Infection 4.7 HIV Diagnosis, Antiretroviral Therapy & Prevention 4.8 Opportunistic Infections & Sexually Transmitted Infections 4.9 Fever of Unknown Origin, Neutropenic Fever & Toxic Shock 4.10 Travel-Related Illness, Vector-Borne Disease & Outbreaks 4.11 Infection Prevention, Nosocomial Infection & Postexposure Prophylaxis 4.12 Rheumatic Fever, Poststreptococcal Disease, Enteric & Hepatic Infections

6 Chapter 5: Pulmonary Disease (9% of Exam)

5.1 COPD: Diagnosis, GOLD Classification & Initial Pharmacotherapy 5.2 Interventions That Reduce COPD Mortality & Exacerbation Management 5.3 Asthma: Diagnosis, Stepwise Therapy & Status Asthmaticus 5.4 Interstitial Lung Disease & Idiopathic Pulmonary Fibrosis 5.5 Sarcoidosis, Hypersensitivity Pneumonitis & Occupational Lung Disease 5.6 Pulmonary Embolism: Diagnosis, Risk Stratification & Anticoagulation 5.7 Pulmonary Hypertension & Sleep-Disordered Breathing 5.8 Acute Respiratory Distress Syndrome & Mechanical Ventilation 5.9 Pleural Disease, Empyema & Pneumothorax 5.10 Bronchiectasis, Cystic Fibrosis & Restrictive Lung Disease 5.11 Evaluation of Cough, Dyspnea, Hemoptysis & the Solitary Pulmonary Nodule

7 Chapter 6: Rheumatology & Orthopedics (9% of Exam)

6.1 Rheumatoid Arthritis: Diagnosis & Systemic Manifestations 6.2 Antirheumatic Pharmacotherapy & the Spondyloarthropathies 6.3 Gout: Pathophysiology & Acute Management 6.4 Urate-Lowering Therapy & Calcium Pyrophosphate Deposition Disease 6.5 Osteoarthritis 6.6 Systemic Lupus Erythematosus 6.7 Systemic Sclerosis, Sjogren Syndrome & Inflammatory Myopathies 6.8 The Vasculitides 6.9 Regional Musculoskeletal Syndromes, Back Pain & Sports Injuries 6.10 Other Primary Rheumatic Disorders & Mixed Connective Tissue Disease 6.11 Osteonecrosis & Metabolic Bone Disease

8 Chapter 7: Hematology (6% of Exam)

7.1 Approach to Anemia & the Microcytic Anemias 7.2 Macrocytic, Normocytic & Hemolytic Anemias 7.3 Hemoglobinopathies, Thalassemias & Paroxysmal Nocturnal Hemoglobinuria 7.4 Platelet Disorders, Thrombocytopenia & the Bleeding Patient 7.5 Coagulation Factor Disorders, Thrombophilia & Anticoagulant Reversal 7.6 Acute Leukemias, Chronic Leukemias & Myeloproliferative Neoplasms 7.7 Lymphomas & Plasma Cell Disorders 7.8 Myelodysplastic Syndrome, Myeloproliferative Neoplasms & Porphyria 7.9 Transfusion Medicine & Late Complications of Transplantation

9 Chapter 8: Medical Oncology (6% of Exam)

8.1 Breast, Lung, Colorectal & Prostate Cancer 8.2 Oncologic Emergencies 8.3 Genitourinary & Gynecologic Malignancies 8.4 Head and Neck, Bone & Soft Tissue Cancer and Cancer of Unknown Primary 8.5 Complications of Cancer & Its Treatment 8.6 Cancer Prevention, Survivorship & Psychosocial Care

10 Chapter 9: Nephrology & Urology (6% of Exam)

9.1 Acute Kidney Injury: Staging, Etiology & Urine Microscopy 9.2 Glomerular Disorders & Nephrotic Syndrome 9.3 Nephritic Syndromes, RPGN & Indications for Renal Replacement Therapy 9.4 Chronic Kidney Disease: Staging & Progression Retardation 9.5 Complications of Chronic Kidney Disease: Anemia, CKD-MBD & Acidosis 9.6 Hyponatremia, Hypernatremia & Water Balance 9.7 Potassium Disorders & Systematic Acid-Base Analysis 9.8 Renal Tubular Acidosis & Nephrolithiasis 9.9 Prostate Disorders, Urinary Incontinence & Other Urologic Conditions 9.10 Cystic Kidney Disease, Obstructive Uropathy, Tubulointerstitial Disease & Hematuria

11 Chapter 10: Neurology (4% of Exam)

10.1 Acute Ischemic Stroke: Syndromes & Reperfusion 10.2 Transient Ischemic Attack, Secondary Prevention & Hemorrhagic Stroke 10.3 Headache & Facial Pain 10.4 Seizures, Epilepsy & Movement Disorders 10.5 Multiple Sclerosis & Neuromuscular Junction Disorders 10.6 Motor Neuron Disease & Acute Peripheral Neuropathy 10.7 Cranial Neuropathies & Neuro-Ophthalmology 10.8 Peripheral Neuropathies, CNS Tumors & Other Neurologic Disorders

12 Chapter 11: Psychiatry & Behavioral Health (4% of Exam)

11.1 Major Depressive Disorder & Medical Mimics 11.2 Antidepressant Pharmacotherapy & Treatment-Resistant Depression 11.3 Bipolar Disorder, Mood Stabilizers & Lithium Toxicity 11.4 Anxiety, Stress-Related & Obsessive-Compulsive Disorders 11.5 Alcohol Use Disorder & Withdrawal 11.6 Pharmacotherapy for Alcohol & Opioid Use Disorder 11.7 Toxidromes, Psychiatric Emergencies & Suicide Risk Assessment 11.8 Psychotic, Somatic Symptom, Factitious & Personality Disorders 11.9 Eating Disorders, Sleep Disorders & Sexual Health

13 Chapter 12: Dermatology (3% of Exam)

12.1 Dermatitis, Papulosquamous & Inflammatory Dermatoses 12.2 Acne, Rosacea & Cutaneous Infections 12.3 Herpes Zoster & Autoimmune Blistering Diseases 12.4 Nodules, Tumors & Cutaneous Oncology 12.5 Dermatologic Emergencies & Severe Cutaneous Adverse Reactions 12.6 Pigment Disorders, Alopecia, Nail Disease & Photosensitivity 12.7 Vascular Dermatoses, Environmental Injury & Cutaneous Signs of Systemic Disease

14 Chapter 13: Obstetrics & Gynecology / Women's Health (3% of Exam)

13.1 Contraception, Preconception Care & Teratogenicity 13.2 Hypertensive Disorders of Pregnancy & Gestational Diabetes 13.3 Thyroid Disease & Venous Thromboembolism in Pregnancy 13.4 Menopause & Menopausal Hormone Therapy 13.5 Abnormal Uterine Bleeding, Endometrial Disease & Gynecologic Cancer Screening 13.6 Breast Disorders & Diseases of the Vulva and Vagina 13.7 Menstrual Disorders, Fibroids, Endometriosis & Early Pregnancy Complications

15 Chapter 14: Geriatric Syndromes (3% of Exam)

14.1 Comprehensive Geriatric Assessment & Frailty 14.2 Falls, Gait Assessment & Polypharmacy 14.3 Urinary Incontinence & Pressure Injuries in Older Adults 14.4 Mild Cognitive Impairment, Dementia & Its Subtypes 14.5 Delirium & the Pharmacotherapy of Cognitive Disorders 14.6 Palliative Care, Hospice & Advance Care Planning 14.7 Chronic Wounds, Nutrition, Swallowing, Constipation & Hip Fracture 14.8 Sensory Impairment, Dizziness, Elder Mistreatment & Care Settings

16 Chapter 15: Allergy & Immunology (2% of Exam)

15.1 Anaphylaxis: Recognition & Emergency Management 15.2 Urticaria & Angioedema 15.3 Drug Allergy, Desensitization & Adult Immunodeficiency 15.4 Food Allergy, Insect Venom Hypersensitivity, Serum Sickness & Contrast Reactions 15.5 Rhinitis, Conjunctivitis, Eosinophilic & Mast Cell Disorders

17 Chapter 16: Preventive Medicine, Immunization & Clinical Epidemiology

16.1 The USPSTF Framework & Evidence-Based Cancer Screening 16.2 Cardiovascular & Metabolic Screening and Primary Prevention 16.3 Adult Immunization & Vaccines in Special Populations 16.4 Clinical Epidemiology, Biostatistics & Study Design

18 Chapter 17: Miscellaneous - Ethics, Patient Safety & Quality Improvement (2% of Exam)

17.1 Principles of Bioethics & Decisional Capacity 17.2 Informed Consent, Treatment Refusal & Special Scenarios 17.3 Surrogate Decision-Making, Advance Directives & Confidentiality 17.4 Patient Safety Science, Medical Error & Diagnostic Reasoning 17.5 Quality Improvement Methods, Health Disparities & Health Equity

19 Chapter 18: Perioperative Medicine & Medical Consultation

18.1 Preoperative Cardiovascular Risk Assessment 18.2 Preoperative Pulmonary Risk & Perioperative Medication Management 18.3 Perioperative Anticoagulation, Bridging & Postoperative Complications

20 Chapter 19: Ophthalmology (1% of Exam)

19.1 The Acute Red Eye & Ophthalmic Emergencies 19.2 Painless Vision Loss & Chronic Ophthalmic Disease 19.3 Uveitis, Scleritis & Orbital Disease

21 Chapter 20: Otolaryngology & Dental Medicine (1% of Exam)

20.1 Dizziness, Vertigo & Epistaxis 20.2 Ear Disorders, Hearing Loss & Upper Respiratory Infections 20.3 Oral Cavity, Salivary Gland, Laryngeal & Taste and Smell Disorders

2.9 Hypoglycemia, Endocrine Tumors, Polyglandular Syndromes & Severe Hypertriglyceridemia

Key Takeaways Explain This Topic AI

Hypoglycemia not due to insulinoma, endocrine tumors, polyglandular autoimmune disorders and hypothalamic disorders are four separate named blueprint subsections.

Whipple triad plus a plasma insulin, C-peptide and proinsulin panel drawn during hypoglycemia distinguishes insulinoma from sulfonylurea use and from surreptitious insulin injection.

Exogenous insulin administration produces high insulin with suppressed C-peptide, whereas insulinoma and sulfonylurea both produce high insulin with high C-peptide.

Carcinoid syndrome implies hepatic metastases or a bronchial primary, because gut-derived serotonin is otherwise cleared by first-pass hepatic metabolism.

Chylomicronemia syndrome with triglycerides above roughly 1,000 mg/dL causes pancreatitis and is treated with fat restriction and fibrate therapy rather than with statins.

Last updated: August 2026

1. Evaluating Hypoglycemia in a Patient Without Diabetes

Hypoglycemia should be pursued only when Whipple triad is satisfied: symptoms consistent with hypoglycemia, a documented low plasma glucose at the time of symptoms, and relief of symptoms when glucose is raised . A capillary reading alone is insufficient.

The critical maneuver is drawing the diagnostic panel while the patient is hypoglycemic , before glucose is given. Once glucose is corrected the opportunity is gone.

• Cause Insulin C-peptide Proinsulin Sulfonylurea screen Beta-hydroxybutyrate
• Insulinoma High High High Negative Low
• Sulfonylurea / meglitinide High High High Positive Low
• Exogenous insulin Very high Suppressed Low Negative Low
• Non-islet tumor (IGF-2) Low Low Low Negative Low
• Fasting / alcohol / adrenal insufficiency Low Low Low Negative High

The single most testable discriminator is C-peptide. Endogenous insulin is secreted as proinsulin and cleaved, releasing equimolar C-peptide; pharmaceutical insulin contains none. High insulin with a suppressed C-peptide therefore means injected insulin — factitious or malicious administration — and the differential includes health care workers and relatives of people with diabetes. High insulin with a high C-peptide means the pancreas is secreting, and the sulfonylurea screen then separates a drug effect from an insulinoma.

Non-islet cell tumor hypoglycemia is caused by large mesenchymal or hepatic tumors secreting incompletely processed insulin-like growth factor 2, producing hypoglycemia with suppressed insulin and C-peptide.

Post-bariatric hypoglycemia is a late postprandial hyperinsulinemic hypoglycemia occurring one to three hours after eating, typically years after Roux-en-Y gastric bypass; it is managed with dietary modification rather than surgery.

2. Insulinoma

A usually small, usually benign, usually solitary pancreatic islet cell tumor causing fasting hypoglycemia. Confirmation classically uses a supervised 72-hour fast . Because the lesion is often under 2 cm, cross-sectional imaging may be negative and endoscopic ultrasound is more sensitive. About 10% are associated with multiple endocrine neoplasia type 1 , so a young patient or one with a suggestive family history should be evaluated for coexisting hyperparathyroidism and pituitary disease. Treatment is surgical enucleation.

3. Carcinoid Syndrome

Neuroendocrine tumors secreting serotonin and other vasoactive mediators. The classic tetrad is episodic flushing, secretory diarrhea, wheezing and, late, right-sided valvular heart disease (tricuspid regurgitation and pulmonic stenosis).

The reasoning point that makes this a good exam item: a midgut carcinoid confined to the bowel does not cause the syndrome. Portal venous drainage delivers serotonin to the liver, which inactivates it on first pass. The syndrome therefore implies hepatic metastases — bypassing first-pass clearance — or a primary outside the portal system, such as a bronchial carcinoid. Right-sided valve involvement follows the same logic: the lungs inactivate the mediators before they reach the left heart.

Diagnosis uses 24-hour urinary 5-hydroxyindoleacetic acid , with dietary restriction of serotonin-rich foods beforehand. Somatostatin analogues control symptoms and slow progression. Carcinoid crisis — profound hypotension and bronchospasm precipitated by anesthesia or tumor manipulation — is treated with octreotide, not with catecholamines, which can worsen it.

4. Multiple Endocrine Neoplasia

• Syndrome Components Genetics
• MEN 1 Parathyroid hyperplasia, p ancreatic islet tumors, p ituitary adenoma (the "3 Ps") MEN1 tumor suppressor
• MEN 2A Medullary thyroid carcinoma, pheochromocytoma, parathyroid hyperplasia RET proto-oncogene
• MEN 2B Medullary thyroid carcinoma, pheochromocytoma, mucosal neuromas, marfanoid habitus RET proto-oncogene

Two management rules: in any MEN 2 patient undergoing surgery, pheochromocytoma must be excluded and treated first , because operating on an unblocked pheochromocytoma can precipitate a fatal hypertensive crisis. And in MEN 1, hyperparathyroidism is usually the earliest manifestation.

5. Polyglandular Autoimmune Syndromes

The blueprint names polyglandular autoimmune disorders with the subtopic multiple endocrine hypofunction . The exam concept is simple and high-yield: one autoimmune endocrinopathy predicts others.

Syndrome Core features Notes

Type 1 (APECED) Chronic mucocutaneous candidiasis, hypoparathyroidism, adrenal insufficiency Childhood onset; AIRE mutation

Type 2 (Schmidt) Adrenal insufficiency plus autoimmune thyroid disease and/or type 1 diabetes Adult onset; far more common

Associated conditions include pernicious anemia, celiac disease, vitiligo, alopecia areata and premature ovarian insufficiency.

The clinical trap: in a patient with known type 1 diabetes and autoimmune thyroid disease, a falling insulin requirement with unexplained hypoglycemia, fatigue, hyperkalemia and hyponatremia signals developing adrenal insufficiency , not improving diabetes. Similarly, starting levothyroxine in someone with unrecognized adrenal insufficiency can precipitate adrenal crisis by accelerating cortisol clearance — glucocorticoid replacement must come first .

6. Hypothalamic Disorders

A separately named blueprint subsection. Hypothalamic lesions — craniopharyngioma, germinoma, sarcoidosis, Langerhans cell histiocytosis, infiltrative disease, radiation — produce a distinctive combination that a purely pituitary lesion does not:

Central diabetes insipidus (arginine vasopressin deficiency)

Hyperprolactinemia from stalk effect — loss of dopaminergic inhibition, producing a modest prolactin elevation, in contrast to the marked elevation of a true prolactinoma

Disordered thirst, temperature regulation, satiety and sleep-wake cycling

Marked hyperphagia with obesity, thermal dysregulation and adipsia points to the hypothalamus rather than the pituitary.

7. Chylomicronemia Syndrome

Listed under lipid disorders and separated from ordinary hypertriglyceridemia because both the risk and the treatment differ. Severe hypertriglyceridemia, generally above roughly 1,000 mg/dL , causes acute pancreatitis , and may produce eruptive xanthomas, lipemia retinalis and lipemic serum.

Familial chylomicronemia syndrome results from lipoprotein lipase pathway defects and presents in childhood. Far more commonly, adults have multifactorial chylomicronemia — an underlying genetic predisposition unmasked by uncontrolled diabetes, alcohol, obesity, hypothyroidism, pregnancy, estrogen therapy or a thiazide.

Management differs from routine lipid management in a way that is frequently tested:

The target of therapy is pancreatitis prevention , not atherosclerotic risk reduction.

Fibrates , not statins, are first-line; severe dietary fat restriction is essential; omega-3 fatty acids are adjunctive.

Remove secondary contributors: control diabetes, stop alcohol, discontinue oral estrogen.

In acute hypertriglyceridemic pancreatitis, insulin infusion and, in refractory cases, apheresis lower triglycerides rapidly.

Artifact caution: severe lipemia interferes with laboratory assays and can produce spurious hyponatremia (pseudohyponatremia).