Granuloma annulare is part of the differential
A wide range of diseases comprise the differential diagnosis of sarcoidosis. These diseases include:9
- Granuloma annulare. It is also a granulomatous skin disease, but it appears as single or multiple rings.
- Rheumatoid nodules. These usually appear in the context of a diagnosis of rheumatoid arthritis.
- Granulomatous mycosis fungoides. This type of cutaneous lymphoma has many clinical forms, including granuloma formation.
- Syringoma. On inspection, you’ll see small, firm adnexal benign tumors that usually appear around the upper cheeks and lower eyelids
- Xanthelasma. These are benign, yellow macules, papules, or plaques that tend to appear on the eyelids. Patients with xanthelasma often have a lipid disorder.
- Lichen planus. This is a very pruritic skin involvement with pink to violaceous papules and plaques. It may present in different locations, but the most common areas are the wrists and ankles.
- Granulomatous rosacea. This is a variant of rosacea characterized by uniform papules on the face.
Clinical findings, biopsy clinch the diagnosis
The diagnosis of sarcoidosis is made by a combination of clinical and histologic findings.1
- Clinical findings. Cutaneous involvement is either “specific” or “nonspecific.”
- With specific cutaneous involvement, which our patient had, you’ll see typical noncaseating granulomas, with no evidence of infection or a foreign body. It may be disfiguring, but it’s almost always nontender and it is rarely ulcerative.
- With nonspecific cutaneous involvement, you’ll see erythema nodosum lesions, especially on the legs. The serum angiotensin-converting enzyme (ACE) level is elevated in many of these patients.