Diagnosis: Pityriasis lichenoides et varioliformis acuta (PLEVA)
This case presents a 20-year-old male with a 3-week history of a rapidly evolving rash characterized by polymorphous crops of papules and necrotic lesions on the trunk. The lesions exhibited a distinctive appearance, raising suspicion for a specific papulosquamous disorder, ultimately leading to the diagnosis after thorough clinical evaluation.
A 20-year-old male presented with a 3-week history of a pruritic rash primarily affecting the trunk. On examination, the skin revealed erythematous papules that progressed to necrotic lesions, with some lesions exhibiting crust formation. The distribution was symmetrical, and there was no involvement of mucosal surfaces. The patient reported mild systemic symptoms, including low-grade fever and malaise.Duration: 3 weeks.Distribution: Predominantly on the trunk.Lesion characteristics: Erythematous papules evolving to necrotic lesions.Associated symptoms: Mild pruritus and systemic symptoms.Prior treatments: None reported.
The patient noted that the rash began suddenly after a recent viral upper respiratory infection. He denied any known drug allergies or recent medication changes. His past medical history was unremarkable, and there was no significant family history of skin disorders. Social history revealed no recent travel or exposure to new environments. He had been in good health prior to the onset of the rash.Onset: Sudden onset following a viral illness.Triggers: Possible viral infection; no known drug exposure.Past medical history: Unremarkable.Family history: No significant skin disorders reported.Social history: No recent travel or exposure to new environments.
Acute / First-Line ManagementTopical corticosteroids (e.g., clobetasol propionate 0.05% ointment applied twice daily) to reduce inflammation.Systemic corticosteroids may be considered for extensive disease (e.g., prednisone 1 mg/kg/day with a taper over 2-4 weeks).Supportive care including antihistamines for pruritus.Workup and Diagnostic ConfirmationClinical diagnosis based on characteristic lesions and history; biopsy may confirm the diagnosis.Histopathological examination typically reveals a mixed inflammatory infiltrate with necrosis.Consider laboratory tests to rule out associated conditions (e.g., viral serologies).Long-Term ManagementMonitor for recurrences; most patients have a self-limited course.In cases of recurrence, consider phototherapy or systemic immunosuppressants like methotrexate.Patient education regarding the benign nature of the condition and reassurance.
Sweet's syndrome: Characterized by painful erythematous plaques and systemic symptoms; often associated with underlying malignancies or infections.Vasculitis: May present with necrotic lesions but usually has systemic involvement and specific laboratory findings.Graft-versus-host disease: Occurs post-transplant; presents with polymorphous rash and mucosal involvement.Drug eruption: Consider recent medications; typically presents with widespread lesions and pruritus.Infectious etiology (e.g., viral exanthem): May mimic PLEVA but often has a clear infectious origin and systemic symptoms.Psoriasis: Chronic plaque psoriasis has a different morphology and is often associated with a family history.Necrotizing fasciitis: Rapid progression and systemic symptoms differentiate it; requires urgent intervention.
High-Yield PearlsClinical presentation: The characteristic polymorphous crops of papules and necrotic lesions are key to diagnosis.Histopathology: Biopsy typically shows a mixed inflammatory infiltrate with necrosis.Triggers: Often associated with viral infections; consider the patient’s recent history.Management: Topical and systemic corticosteroids are first-line treatments.Self-limited course: Most patients experience spontaneous resolution over weeks to months.Pityriasis lichenoides et varioliformis acuta is a self-limited disorder that requires careful differentiation from other papulosquamous diseases.
Tags: PLEVA, pityriasis lichenoides