Sarcoidosis nodules under the skin: what should you know?

In skin sarcoidosis, inflammation can form firm papules or nodules within or just beneath the skin. They may match the surrounding skin or look red-brown or purple. A nodule can be painless and slow to change, although tenderness, itch, or several lesions may occur. Common locations include the face, trunk, arms, and areas around old scars.

A lump under the skin is not specific to sarcoidosis. Boils are often painful, warm, and linked with infection; basal cell carcinoma may appear as a persistent changing growth. A clinician may also consider cysts, benign growths, or other inflammatory causes. The lump itself is a symptom, not a prediction of its diagnosis.

Book an assessment for a new, persistent, enlarging, or unexplained lump. Do not squeeze, pierce, or massage it, as this can irritate the tissue or worsen an infection. Note its location, tenderness, colour, speed of change, and whether similar nodules have appeared elsewhere.

The clinician may inspect and feel the lesion, review your general symptoms, and suggest imaging or a biopsy when the cause is uncertain. If skin sarcoidosis is confirmed and treatment is needed, a steroid injection into the skin may be considered for selected lesions. Treatment is tailored to the lesion and your wider health.

Get prompt care if a lump becomes rapidly larger, hot, very painful, draining, or surrounded by spreading redness, or if you develop fever. Seek urgent help for breathing trouble, chest pain, severe eye pain, or sudden vision changes. Otherwise, arrange a routine review rather than monitoring an unexplained lump indefinitely.

What features make this lump more consistent with inflammation, infection, or another growth? Is a biopsy or scan needed? Could there be nodules elsewhere? If sarcoidosis is confirmed, would local treatment be enough, and what changes should prompt rechecking?