12.7 Vascular Dermatoses, Environmental Injury & Cutaneous Signs of Systemic Disease

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

12.7 Vascular Dermatoses, Environmental Injury & Cutaneous Signs of Systemic Disease

Key Takeaways Explain This Topic AI

Vascular dermatoses, dermatologic immunology, cutaneous manifestations of nutritional deficiencies, environmental injury of skin and pressure injuries are enumerated blueprint subsections.

Erythema nodosum is a septal panniculitis whose leading causes are streptococcal infection, sarcoidosis, inflammatory bowel disease, drugs and tuberculosis.

Palpable purpura indicates leukocytoclastic vasculitis and requires evaluation for systemic involvement, particularly renal.

Pellagra from niacin deficiency causes a photodistributed dermatitis with diarrhea and dementia.

Frostbite is rewarmed rapidly in warm water and definitive tissue demarcation is deferred for weeks.

Last updated: August 2026

1. Erythema Nodosum

A septal panniculitis presenting as tender, warm, erythematous subcutaneous nodules on the anterior shins , typically bilateral. The lesions do not ulcerate and heal without scarring, evolving through bruise-like color changes.

Causes — the differential is the exam content:

Category Causes

Infection Streptococcal pharyngitis (the most common identified cause), tuberculosis, coccidioidomycosis, histoplasmosis, Yersinia

• Inflammatory Sarcoidosis (Lofgren syndrome), inflammatory bowel disease , Behcet disease
• Drugs Oral contraceptives , sulfonamides, penicillins
• Other Pregnancy , lymphoma, idiopathic in a large fraction

Lofgren syndrome — erythema nodosum, bilateral hilar lymphadenopathy , fever and polyarthritis — is an acute sarcoidosis presentation with an excellent prognosis that frequently resolves without corticosteroids.

Evaluation of a first episode: history and examination, throat culture or antistreptolysin O, chest radiograph (for hilar adenopathy or tuberculosis), tuberculin or interferon-gamma testing, and a pregnancy test. Treatment is of the underlying cause plus NSAIDs, rest and leg elevation.

2. Leukocytoclastic Vasculitis and Palpable Purpura

Palpable purpura is the cutaneous signature of small-vessel vasculitis — it is palpable because inflammation and extravasation raise the lesion above the skin, distinguishing it from the flat purpura of thrombocytopenia.

Causes:

• Drugs — the most common cause: beta-lactams, sulfonamides, NSAIDs, allopurinol, thiazides
• Infection — streptococcal, hepatitis B and C, endocarditis

IgA vasculitis (Henoch-Schonlein purpura) — purpura on the lower extremities and buttocks, arthralgia, abdominal pain and IgA nephropathy ; more severe in adults

• Cryoglobulinemia — strongly associated with hepatitis C
• ANCA-associated vasculitis , connective tissue disease, malignancy

The essential step is determining whether the vasculitis is skin-limited or systemic. Obtain a urinalysis looking for hematuria, red cell casts and proteinuria , plus creatinine, complete blood count, liver enzymes, hepatitis serologies, complement levels, ANCA, cryoglobulins and antinuclear antibody. Skin-limited disease resolving with drug withdrawal is common; renal involvement changes management entirely.

3. Erythema Multiforme

Targetoid lesions with three concentric zones, favoring the acral surfaces — palms, soles, extensor extremities — and spreading centrally.

Erythema multiforme is usually infectious , most often herpes simplex virus (recurrent erythema multiforme is nearly always HSV-driven and is prevented with suppressive antiviral therapy), and Mycoplasma pneumoniae in younger patients. This is a key contrast: Stevens-Johnson syndrome and toxic epidermal necrolysis are usually drug-induced , present with atypical targets and dusky macules on the trunk , involve mucosa extensively, and carry substantial mortality.

4. Leg Ulcers

An enumerated topic under vascular dermatoses, and a common source of misdiagnosis.

Venous Arterial Neuropathic

Location Medial malleolus (gaiter area) Distal toes, pressure points, lateral malleolus Plantar pressure points

Appearance Irregular, shallow, exudative Punched-out , dry, pale or necrotic base Punched-out with surrounding callus

Pain Aching, better with elevation Severe, worse with elevation , better dependent Painless

Surrounding skin Hemosiderin staining , lipodermatosclerosis, varicosities Shiny, hairless, cool, absent pulses Callus, deformity

• Key test Duplex ultrasound Ankle-brachial index Monofilament testing
• Treatment Compression Revascularization Offloading

Compression is the treatment for venous ulcers and is contraindicated in significant arterial disease — so an ankle-brachial index should be measured before applying compression . Applying compression to an ischemic limb causes tissue necrosis, which is exactly the trap exam items are built around.

Pyoderma gangrenosum should be considered for an ulcer with a violaceous undermined border that enlarges rapidly and is exquisitely painful, often with pathergy (worsening after debridement). It is associated with inflammatory bowel disease, inflammatory arthritis and hematologic malignancy. Surgical debridement worsens it — the treatment is immunosuppression, and recognizing this prevents serious harm.

5. Cutaneous Manifestations of Nutritional Deficiency

A named blueprint subsection.

Deficiency Skin findings Other features

Niacin (B3) — pellagra Photodistributed dermatitis , Casal necklace Diarrhea, dementia , death; seen in alcohol use, carcinoid, isoniazid

Vitamin C — scurvy Perifollicular hemorrhage, corkscrew hairs , gingival bleeding Poor wound healing, arthralgia

Zinc Acrodermatitis enteropathica — periorificial and acral erosive dermatitis Alopecia, diarrhea, impaired taste; after bariatric surgery, in parenteral nutrition

• Vitamin A Follicular hyperkeratosis (phrynoderma) Night blindness , xerophthalmia
• Essential fatty acids Dry scaly dermatitis Prolonged fat-free parenteral nutrition
• Vitamin K Purpura, easy bruising Elevated prothrombin time
• Iron Koilonychia , angular cheilitis, glossitis Microcytic anemia
• B12 / folate Hyperpigmentation, glossitis Macrocytic anemia; B12 also myeloneuropathy

Think of these after bariatric surgery, in chronic alcohol use, in malabsorption, in restrictive eating disorders, and in prolonged parenteral nutrition — the same populations in which the exam places them.

6. Environmental Injury and Pressure Injuries

Frostbite — freezing injury with initial numbness and waxy pallor. Rewarm rapidly in circulating water at 37 to 39 degrees Celsius , and do not rewarm if there is any risk of refreezing, since freeze-thaw-refreeze cycles are far more damaging. Rewarming is painful and requires analgesia. Do not debride early : the extent of tissue loss cannot be judged for weeks, and premature amputation removes salvageable tissue. Clear blisters may be drained; hemorrhagic blisters indicate deeper injury and are left intact.

Burns — assess depth and total body surface area involved. Superficial partial-thickness burns are painful and blanch; full-thickness burns are insensate, leathery and do not blanch . Circumferential full-thickness burns risk compartment syndrome and require escharotomy. Fluid resuscitation is calculated from body surface area involved, and inhalation injury should be suspected with facial burns, singed nasal hairs, carbonaceous sputum or hoarseness.

Pressure injuries — an enumerated subsection under both Dermatology and Geriatric Syndromes, covered in detail with geriatric syndromes. The essential dermatologic point is staging by the deepest tissue visible, and that a stage cannot be assigned when the wound base is obscured by slough or eschar (unstageable), while deep tissue pressure injury appears as a persistent non-blanchable deep red, maroon or purple discoloration of intact skin.