Hello,
Thanks for posting your query.
I understand your concern as a vigilant and caring parent.
Your son is most probably having a penile papule either due to a viral infection or a local inflammation.
Most penile papules do not have a serious cause, but some are infectious and may be contagious . The most common reason could be a molluscum contagiosum or a viral infection common in children.These are pearly white papule(bumps) with a central umbilication .Usually seen in children, it occurs in adults as a sexually transmitted disease. Other types of close contact or usage of towels etc can also transmit the disease.
These are usually self limiting and can go away by themselves after a few months or even years. Except for the contact transmission risk, these are comparatively harmless eruptions.
Removal is easy with needle excision and curretage, cryo freezing or electro cautery.
Another possibility is an inflammation of the hair follicles and sebaceous (sweat) glands. These are a normal part of the skin's anatomy and are commonly found on the penile shaft, particularly on the ventral surface (underside). They may be visible as small nodules or might only be felt as small lumps in the skin. They will have a hair arising from them that reveals their true nature.
In any case if the lesions are itchy or painful or spreading or oozing the next best step would be to see a dermatologist to get a confirmed diagnosis . The treatment would depend on the diagnosis . Most penile papules in children would self resolve in few months unless complicated or infectious.
Hope I have answered your query.
I'll be available for any follow up queries.
Regards

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