Papules

Name: Papules - Pulse Reference
Published: 2022-08-02T13:08:11+00:00

Differential Diagnosis

Key distinguishing features of the most common diagnoses

	Acne	Scabies	Viral Wart	C. de M. Spot	Skin Tag
Itchy	No	Yes	No	No	No
Characteristic Distribution	Yes	Yes	No	Yes	No
Red	Yes	Yes	No	Yes	No
Associated Lesions	Yes	Yes	No	No	No
History of Contact	No	Yes	Possible	No	No

In practice, very few investigations are needed with this presentation: A lipid screen is required in the presence of xanthomata; genital warts require referral for screening for other STDs; thorough investigation may be needed in the very rare case where underlying malignancy is possible (e.g. acanthosis nigricans); and obscure rashes or solitary papules may occasionally require excision biopsy for a definitive diagnosis.

Bear in mind that skin cancer is usually uppermost in the patient’s mind, especially in subacute or chronic cases – so provide appropriate reassurance.
In obscure solitary lesions, record clinical findings carefully and arrange to review in due course.
Itchy, asymmetrical grouped papules are likely to be insect bites, although the patient may take some convincing!

An enlarging dark blue or blue-black papule may be a malignant melanoma, blue naevus or Kaposi’s sarcoma. Refer for urgent opinion.
Brown, skin-coloured papules crowded around the nose of a child may be tuberous sclerosis. This can be associated with serious systemic pathology so refer for expert opinion.
An intensely itchy papular rash which is worse at night and has no other obvious cause is likely to be scabies, even if scabetic burrows are not evident – treat on suspicion.