What is the diagnosis and recommended treatment for a 5-year-old male presenting with white bumps on the penis and white spots on the chest and lower abdomen?

Diagnosis: Pearly Penile Papules and Molluscum Contagiosum

The most likely diagnosis for a 5-year-old male with white bumps on the penis and white spots on the chest and lower abdomen is a combination of pearly penile papules (PPP) on the penis and molluscum contagiosum on the trunk, both of which are benign conditions requiring only reassurance in most cases. 1

Clinical Differentiation

Pearly Penile Papules

• PPP present as uniform, dome-shaped white or flesh-colored papules arranged in one to two rows around the corona of the glans penis 1
• These are benign, normal anatomical variants that can appear during childhood or adolescence and have no association with sexually transmitted infections 1
• No treatment is necessary unless there is excessive parental or patient concern after adequate counseling 1
• The key distinguishing feature is their uniform appearance, symmetric distribution around the corona, and lack of other symptoms 2, 1

Molluscum Contagiosum (Likely for Trunk Lesions)

• White or flesh-colored papules on the chest and abdomen in a 5-year-old are most consistent with molluscum contagiosum, a common viral infection in children
• These lesions are typically dome-shaped with central umbilication and spread through direct contact
• Self-limited condition that resolves spontaneously over months to years

Important Differential Diagnoses to Exclude

Lichen Sclerosus

• Presents as white, smooth atrophic plaques in the anogenital region with possible distortion of anatomy 3
• Children can present as young as 6 months but average around 5 years of age 3
• Males typically present with difficulty retracting the foreskin leading to phimosis, not isolated white bumps 4, 3
• Requires biopsy if there is diagnostic uncertainty, failure to respond to treatment, or atypical features 4
• First-line treatment is ultrapotent topical corticosteroids applied intermittently 3

Genital Warts (Condyloma Acuminata)

• Caused by low-risk HPV types 6 and 11, presenting as papillomatous lesions 2
• Unlike PPP, these lesions are irregular, may coalesce, and can occur anywhere on the genitalia, not just the corona 2
• Would be unusual in a 5-year-old without history of sexual abuse or vertical transmission

Syringoma

• Extremely rare on the penis, presenting as yellow-white papules or brownish-red plaques 5
• Typically occurs in an eruptive fashion on dorsal and lateral aspects of penile shaft 5
• Requires biopsy for definitive diagnosis 5

Recommended Management Algorithm

Step 1: Clinical Examination

• Examine the penile lesions for uniform dome-shaped papules in 1-2 rows around the corona (pathognomonic for PPP) 1
• Assess for any signs of inflammation, atrophy, phimosis, or anatomical distortion that would suggest lichen sclerosus 4, 3
• Examine trunk lesions for central umbilication characteristic of molluscum contagiosum

Step 2: Reassurance vs. Further Evaluation

• If lesions are consistent with PPP (uniform, symmetric, on corona only), provide reassurance that these are normal anatomical variants with no association to infection 1
• If there is any diagnostic uncertainty, atrophic changes, phimosis, or failure of lesions to fit the classic PPP pattern, perform a biopsy 4
• For lichen sclerosus, biopsy is essential before initiating treatment in young patients to confirm diagnosis 4

Step 3: Treatment (Only if Indicated)

• For PPP: No treatment is necessary; if parents insist after counseling, cryotherapy or laser therapy are options with low recurrence rates 1
• For lichen sclerosus: Ultrapotent topical corticosteroids are first-line therapy, with topical tacrolimus or pimecrolimus as alternatives 3
• For molluscum contagiosum: Observation is preferred as lesions are self-limited; treatment options include curettage or cryotherapy if desired

Step 4: Follow-up

• Patients with lichen sclerosus require monitoring every 6-12 months even when asymptomatic due to potential for malignant transformation in adulthood 3
• PPP requires no follow-up as they are benign and stable 1

Critical Clinical Pitfalls

• Do not misdiagnose PPP as genital warts, which can cause unnecessary anxiety and inappropriate treatment 1
• Lichen sclerosus in children has been commonly misdiagnosed as sexual abuse, leading to unnecessary family turmoil 3
• Always consider lichen sclerosus if there is any associated phimosis, atrophy, or anatomical distortion 4, 3
• Biopsy is mandatory if there is any suspicion of premalignant change, persistent hyperkeratosis, erosion, or failure to respond to treatment 4