**Question:** A 50-year-old woman develops pink macules and papules on her hands and forearms in association with a sore throat. The lesions are targetlike, with the centers a dusky violet. A diagnosis of erythema multiforme is made. The most important information obtained from this patient's history is

A. Presence of a viral infection
B. History of recent drug exposure
C. Presence of a bacterial infection
D. History of allergies

**Correct Answer:** B. History of recent drug exposure

**Core Concept:** Erythema multiforme is a rare cutaneous reaction characterized by the formation of target-like macules, papules, and, in severe cases, mucosal involvement. It is typically associated with an underlying cause, most commonly a viral infection or a drug reaction.

**Why the Correct Answer is Right:**

Erythema multiforme is a drug-induced cutaneous reaction that presents with the classic target-like morphology. The correct answer (B) highlights the importance of recent drug exposure as a potential cause for this reaction. In this case, the patient's history of a sore throat could be related to a viral infection, but the focus on a recent drug exposure is crucial for understanding the correct diagnosis and treatment approach.

**Why Each Wrong Option is Incorrect:**

A. Presence of a viral infection (C) is not specific enough to diagnose erythema multiforme, as viral infections can cause other cutaneous reactions as well.

C. Presence of a bacterial infection (C) is also not directly related to the diagnosis of erythema multiforme, as bacterial infections are not typically associated with this condition.

D. History of allergies (D) is irrelevant to the diagnosis of erythema multiforme, as it is a drug reaction and not an allergy.

**Clinical Pearl:**

Erythema multiforme is a clinical diagnosis based on the morphology of the lesions and the patient's history, including potential drug exposure. If a patient presents with this clinical picture, a thorough review of medications taken recently should be performed to identify the potential culprit drug. This will guide the management and prevent misdiagnosis of a viral infection or other skin disorders.