What is the differential diagnosis for a 90-year-old patient with itchy, non-erythematous facial umbilicated papules on bilateral cheeks?

Differential Diagnosis for Itchy, Non-Erythematous Facial Umbilicated Papules in a 90-Year-Old Immunocompetent Patient

In a 90-year-old immunocompetent patient with itchy, non-erythematous umbilicated papules on bilateral cheeks, the differential diagnosis shifts significantly toward age-related benign lesions, with molluscum contagiosum becoming less likely and basal cell carcinoma, fibrous papules, and pruritic dermatoses becoming more prominent considerations.

Key Differential Diagnoses in the Elderly

Basal Cell Carcinoma (BCC)

• BCC commonly presents as pearly papules with smooth surfaces, rolled borders, and telangiectatic vessels, though umbilication can occur with central ulceration 1
• In elderly patients, BCC may appear as pigmented nodular lesions, pigmented patches or plaques, or ulcers depending on subtype and body site 2
• The bilateral cheek location is typical for BCC, as it occurs in sun-exposed areas 1
• Arborizing vessels remain the predominant dermoscopic feature, along with blue, black and gray dots in pigmented variants 2, 3
• Tissue diagnosis via shave biopsy (if raised) or punch biopsy of the most abnormal-appearing area is essential 1

Fibrous Papules of the Face

• Fibrous papules are frequent benign lesions seen in the nasal and perinasal region, occurring in patients aged 18-90 years (mean age 46 years) 4
• These lesions are often clinically misdiagnosed, with the correct diagnosis mentioned in fewer than 50% of cases at initial presentation 4
• The main clinical differential diagnoses include nevus (34% of cases) and basal cell carcinoma (14% of cases) 4
• 83.7% of fibrous papules occur in the nasal region, with none occurring outside the face 4
• Histological diagnosis is often required, with immunohistochemistry for factor XIIIa being positive in most variants 4

Pruritus in Elderly Skin with Secondary Changes

• Elderly patients with pruritus should initially receive emollients with high lipid content and topical steroids for at least 2 weeks to exclude asteatotic eczema 5
• Pruritus in the elderly (Willan's itch) is very common in those over 65 years and may be associated with dry skin, xerosis, or other factors 5
• Chronic scratching can lead to papular changes and lichenification, which may appear as umbilicated lesions 5
• Pruritus alone can rarely be the presenting feature of bullous pemphigoid in the elderly, requiring skin biopsy and indirect immunofluorescence if suspected 5

Molluscum Contagiosum (Less Likely but Possible)

• While typically associated with immunocompromised patients, molluscum can occur in immunocompetent elderly individuals
• The umbilicated appearance and bilateral distribution are classic features
• However, the presence of pruritus and elderly age makes this diagnosis less typical

Critical Diagnostic Approach

Initial Assessment

• Perform detailed examination of the papules looking for pearly appearance, rolled borders, telangiectasia (suggesting BCC), or firm consistency (suggesting fibrous papules) 4, 1
• Assess for signs of chronic scratching, excoriation, or secondary changes from pruritus 5
• Examine the entire skin surface for additional lesions, xerosis, or eczematous changes 5

Diagnostic Testing

• Tissue sampling is essential for definitive diagnosis: use shave biopsy if lesions are raised, or punch biopsy of the most abnormal-appearing area 1
• Consider dermoscopy to look for arborizing vessels, blue-gray dots, or other BCC-specific features 2, 3
• If pruritus is prominent without clear dermatologic cause, check full blood count, ferritin, liver function tests, urea and electrolytes, and thyroid function 5

Management of Pruritus Component

• Initiate emollients with high lipid content and mild topical steroids (1% hydrocortisone) for at least 2 weeks 5
• Avoid sedative antihistamines in elderly patients due to increased risk of dementia and excessive sedation 5
• Consider non-sedating antihistamines such as fexofenadine 180 mg or loratadine 10 mg if pruritus persists 5
• Gabapentin may benefit elderly patients with persistent pruritus not responding to topical treatments 5

Common Pitfalls to Avoid

• Do not assume molluscum contagiosum is the primary diagnosis without considering BCC, as both can present with umbilicated papules in elderly patients 4, 1
• Do not dismiss bilateral facial papules as benign without tissue diagnosis, as BCC can present bilaterally in sun-exposed areas 2, 1
• Do not prescribe sedative antihistamines for pruritus in elderly patients 5
• Do not use crotamiton cream, topical capsaicin, or calamine lotion for elderly skin pruritus 5
• Reassess if symptoms don't improve after initial treatment, and refer to secondary care if there is diagnostic doubt 5