What is the cause and treatment of papules on the hands and feet of a 17-year-old with no recent sexual exposures?

Acute Papular Eruption on Hands and Feet in an Adolescent

In a 17-year-old with papules on hands and feet for two days without sexual exposure, the most likely diagnosis is a viral exanthem (such as papular-purpuric "gloves and socks" syndrome from parvovirus B19 or other viral infections), hand-foot-and-mouth disease, or a hypersensitivity reaction—treatment is primarily supportive with close monitoring for systemic symptoms.

Differential Diagnosis Approach

The acute onset (2 days) and acral distribution (hands and feet) in an adolescent narrows the differential significantly:

Most Likely Viral Etiologies

• Papular-purpuric "gloves and socks" syndrome (PPGSS) presents with edema, erythema, and pruritic petechiae/papules in a "gloves and socks" distribution, often accompanied by fever, lymphadenopathy, and myalgias 1
• PPGSS is typically triggered by parvovirus B19, but has been documented with influenza and other viral infections 1
• Hand-foot-and-mouth disease (enterovirus) causes papulovesicular lesions on palms, soles, and oral mucosa, common in adolescents

Other Considerations Based on Clinical Features

• Keratosis pilaris presents as folliculocentric papules but is chronic, not acute over 2 days 2
• Drug reaction should be considered if any new medications were started within the past 1-2 weeks
• Scabies causes papules but typically involves web spaces, wrists, and is intensely pruritic 3

Immediate Assessment

Key Clinical Features to Evaluate

• Distribution pattern: Symmetric involvement of hands/feet suggests viral etiology; asymmetric or web space involvement suggests scabies 3
• Lesion morphology: Papules vs. papulovesicles vs. purpuric papules 1
• Associated symptoms: Fever, oral lesions, lymphadenopathy, pruritus 1
• Recent illness: Preceding upper respiratory infection or flu-like symptoms 1

What to Rule Out

• Secondary syphilis can cause papulosquamous lesions on palms/soles, but the patient denies sexual exposure and this would be unusual with only 2 days of symptoms 3
• Infection requiring antibiotics: Absence of pustules, yellow crusts, or discharge makes bacterial superinfection unlikely 3

Management Strategy

For Presumed Viral Etiology (Most Likely)

• Supportive care with oral antihistamines for pruritus
• Topical low-potency corticosteroids (hydrocortisone 1-2.5%) if significant inflammation 3
• Avoid hot water exposure and skin irritants 3
• Alcohol-free moisturizers applied twice daily 3
• Self-limited course expected within 1-2 weeks 1

When to Escalate Care

• Obtain bacterial culture if lesions become painful, develop pustules, yellow crusts, or discharge suggesting superinfection 3
• Consider dermatology referral if lesions persist beyond 2-3 weeks, worsen despite supportive care, or if diagnosis remains uncertain 4
• Reassess after 2 weeks for treatment response 3

Critical Pitfalls to Avoid

• Do not prescribe antibiotics empirically without evidence of bacterial infection (pustules, crusting, discharge) 3, 5
• Do not use topical steroids if infection is suspected, as this can worsen bacterial or fungal infections 4
• Do not assume sexually transmitted infection based solely on acral papules—condyloma acuminata affects anogenital regions, not hands and feet 6
• Do not perform HPV testing for papules on hands/feet, as this is not indicated for non-genital lesions 3, 6

Red Flags Requiring Urgent Evaluation

• Fever with rapid progression suggests possible systemic infection requiring cultures and broader workup 3
• Painful lesions with necrosis could indicate rare fungal or atypical bacterial infection in immunocompromised hosts 3
• Immunosuppression history (chemotherapy, transplant, immunomodulators) requires immediate dermatology and infectious disease consultation 3