Dermatology MCQ - Inflammatory Dermatoses - Erythroderma

A 68-year-old man with a history of poorly controlled psoriasis presents with generalized erythema covering over 95% of his body surface area. He has associated fever, malaise, and significant scaling. On examination, you note fine, exfoliative scale, diffuse erythema, and bilateral lower extremity pitting edema. What is the most urgent initial complication to assess for and manage in this patient?

A. Superimposed bacterial skin infection
B. High-output cardiac failure
C. Protein and fluid loss leading to hypovolemia and electrolyte imbalance
D. Underlying cutaneous T-cell lymphoma
E. Hepatic dysfunction from systemic inflammation

Correct Answer: C. Protein and fluid loss leading to hypovolemia and electrolyte imbalance

Explanation:

• The patient is presenting with erythroderma, also known as exfoliative dermatitis. This is a life-threatening dermatologic emergency. The skin's primary function as a barrier is profoundly compromised. The massive inflammation leads to immense insensible fluid loss, increased cutaneous blood flow, and exfoliation that results in significant protein loss. The most immediate, life-threatening complications are hypovolemia, hypoproteinemia, and electrolyte disturbances, which can lead to renal failure and cardiac complications. The pitting edema is a sign of both the high-output state and hypoalbuminemia.

• Why the other options are incorrect (or less urgent):

  • A. Superimposed bacterial skin infection: This is a common and serious complication due to the loss of the skin barrier, but the hemodynamic and metabolic instability from fluid and protein loss is a more immediate threat to life and must be stabilized first.

  • B. High-output cardiac failure: This is a real complication of erythroderma due to the massive shunting of blood to the skin. However, it is a consequence of the hyperdynamic state, which itself is driven by the fluid shifts and metabolic demands. Correcting the hypovolemia and metabolic status is the primary step in managing cardiac strain.

  • D. Underlying cutaneous T-cell lymphoma: While this is an important cause of erythroderma to investigate (e.g., Sézary syndrome), it is not the most urgent complication to manage in the initial resuscitation phase.

  • E. Hepatic dysfunction: This can occur but is not the most immediate, universal complication. The hemodynamic instability takes precedence.

Key Points for Exams

• Common Causes (Mnemonic: "I PRefer SHiNy CAPs"):

  • Idiopathic

  • Psoriasis

  • Reactive (e.g., DRESS)

  • SH (Sézary Syndrome)

  • Contact Dermatitis

  • Atopic Dermatitis

  • Pityriasis Rubra Pilaris (PRP)

  • Drug eruptions are a very common cause.

• Systemic Complications:

  • Thermoregulatory Failure: Inability to conserve heat leads to hypothermia.

  • Hemodynamic Instability: Hypovolemia and high-output cardiac failure.

  • Metabolic: Hypoalbuminemia, electrolyte loss.

  • Infectious: Secondary bacterial infection (impetiginization, cellulitis) and sepsis.

• Management Priorities (The ABCs of Erythroderma):

  1. Hospitalization: Almost always required.

  2. Fluid and Electrolyte Resuscitation: Central venous monitoring may be necessary.

  3. Thermoregulation: Use a warm environment and blankets; avoid cooling the patient.

  4. Skin Care: Topical, low-potency corticosteroids and bland emollients (e.g., petrolatum) to soothe the skin and help restore the barrier.

  5. Identify and Treat the Underlying Cause: This is the definitive management and requires a thorough history, examination, and often skin biopsy.