NEW ORLEANS — Because of its myriad presentations on black skin, sarcoidosis can be called “the great imitator,” Rebat Halder, M.D., said at the annual meeting of the American Academy of Dermatology.
“The appearance on the skin can have many different morphologies,” said Dr. Halder, chair of the department of dermatology at Howard University, Washington.
“It can really fool you: The lesions can be macular, papular, ichthyosiform, nodular, ulcerative, vesicular, annular, or it can simply present as areas of hypopigmentation with no apparent inflammation.”
Sarcoidosis, characterized by noncaseating epithelioid granulomas that may affect any organ system, is uncommon in any group of patients. However, it is about 16 times more common in blacks than in whites, with an incidence of 35-65/100,000 among blacks. Black women in their fourth decade are most commonly affected, with an incidence of about 100/100,000, Dr. Halder said in an interview.
The etiology of sarcoidosis is unknown, although familial clustering has been observed.
For unknown reasons, sarcoidosis is often more aggressive and difficult to treat in blacks. They have a higher rate of relapse, are more likely to experience multiorgan involvement, and have a slightly higher mortality rate than whites.
About 90% of patients have lung involvement, usually fibrosis due to granulomatous lesions.
Skin lesions appear in about 35% of patients. Other affected organs are the eyes, liver, heart, central nervous system, and spleen.
Any suspicious lesions should be biopsied. Typically, histology will show characteristic noncaseating granulomas. Since so many patients have lung involvement, a chest x-ray is imperative, Dr. Halder said. “If you suspect a skin lesion is sarcoidosis, you must search for the disease elsewhere in the body.”
Papular sarcoidosis consists of red-brown papules usually occurring on the face, around the eyes, nose, mouth, and nape of neck.
The papules can be larger, or quite fine, with the skin assuming a sandpaperlike texture, Dr. Halder said.
Lupus pernio lesions are red or purple indurated plaques usually occurring around the nose. These lesions can affect the nasal cartilage or bone and upper respiratory system as well.
Plaquelike sarcoidosis can occur anywhere on the skin, but is most common on the back of the neck and on the arms and legs.
This condition is characterized by round or oval, red-brown to purple, infiltrated plaques.
Ulcerative sarcoidosis can be especially debilitating, especially when it occurs on the palms of the hands or soles of the feet.
These lesions are small but can become quite deep, Dr. Halder commented.
Vesicular sarcoidosis can occur anywhere on the skin and can easily be confused with other blistering diseases or with skin infections.
Hypopigmented sarcoidosis is especially difficult to recognize, he said. “This presents only as areas of the skin without pigment. You would have to consider sarcoidosis along with hypopigmented cutaneous T-cell lymphoma, vitiligo, or tinea versicolor. Again, biopsy is crucial to diagnosis.”
Treatment for skin lesions usually consists of topical or intralesional steroids.
Extensive or recalcitrant disease requires more aggressive treatment, which includes drugs such as oral steroids, methotrexate, allopurinol, thalidomide, or oral retinoids.
There has been some success with infliximab as well, Dr. Halder said.
Adjunctive phototherapy is useful for hypopigmented sarcoidosis, the investigator said.