Enlarging annular plaques and patches

Sarcoidosis is a systemic granulomatous disease that involves the skin and many of the internal organs with an acute or persistent course interrupted by remissions and relapses.1 The etiology is unknown, but it likely represents a granulomatous reaction to an...

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Sarcoidosis is a systemic granulomatous disease that involves the skin and many of the internal organs with an acute or persistent course interrupted by remissions and relapses.¹ The etiology is unknown, but it likely represents a granulomatous reaction to an unknown antigen.² Strong racial proclivity and outbreaks within families suggest a genetic predisposition. It appears likely that multiple genetic factors are to blame.¹

Whatever the trigger, T-cells appear to play a significant role in the genesis of sarcoidosis. T-cells likely propagate an excessive cellular immune reaction, mostly composed of increased numbers of CD4 cells accompanied by the release of interleukin 2, such Th1 cytokines as interferon, and an increase in tumor necrosis factor (TNF) and TNF receptors. The fact that the disease responds well to such anti-TNF drugs as pentoxifylline (Pentopak, Pentoxil, Trental) and infliximab (Remicade) appears to support this theory.³

In addition to the skin, which is involved in at least 25% of cases, other sites of involvement include the lungs, mediastinal and peripheral lymph nodes, eyes, phalangeal bones, myocardium, central nervous system, kidneys, spleen, liver, and parotid glands.

In the United States, black women between the ages of 30 and 39 years have the highest incidence of sarcoidosis (107 cases per 100,000 population). In Europe, the condition is most prevalent in Scandinavia, especially Sweden, with a prevalence of 64 cases per 100,000 population. Sarcoidosis can also affect children.¹

Papules are the most common morphological form of cutaneous sarcoid. These lesions are typically <1 cm in diameter and may be localized or generalized. Commonly affected areas include the face, eyelids, neck, and shoulders, where the lesions are often arranged or coalesce into annular patterns.

Hypopigmentation, obviously more noticeable in darker-skinned patients, may be the earliest sign of sarcoid­osis. Cutaneous involvement is classified as either specific, which reveals granulomas on biopsy, or nonspecific, which is mainly reactive. Erythema nodosum is the most common nonspecific cutaneous lesion of sarcoidosis. Biopsy of erythema nodosum reveals septal panniculitis confined to adipose tissue,⁴ a nonspecific reaction associated with a number of other unrelated diseases and triggers.

The skin lesions of sarcoidosis do not generally correlate with the extent or nature of systemic involvement or with prognosis. However, red to violaceous lesions on the cheeks, ears, nose (especially the nostril rim), and fingers can become severe to the point of disfigurement and may even lead to involvement of underlying bone, cartilage, or upper aerodigestive tract. Such cases are termed lupus pernio, which can also manifest with uveitis and bone cysts. This type of sarcoidosis is most often seen in black women in their fourth or fifth decade of life.⁵

Additional cutaneous forms of sarcoid include ulcerative, subcutaneous, scar, plaque-type, erythrodermic, icthyosiform, alopecia, morpheaform, and mucosal.

Sarcoidosis may first appear with fever, polyarthralgias, uveitis, bilateral hilar adenopathy, and fatigue. Sarcoidosis combined with erythema nodosum is known as Lofgren syndrome, a condition that is far more common in Scandinavian whites and uncommon in American blacks.⁶

Approximately 5% of sarcoidosis cases are asymptomatic and are detected on radiographs of the chest performed for other reasons. Fever may be the only symptom, or sarcoid may be accompanied by weight loss, fatigue, and malaise. The disease can involve virtually every internal organ, and its manifestations are truly protean. It has been called “the great imitator” because of the extreme variation in its presentations.⁷

Blind liver biopsy showing hepatic granulomas is an excellent means of confirming the diagnosis, since about 60% of sarcoid patients will have hepatic involvement. Blood work can reveal an elevated erythrocyte sedimentation rate, leukopenia, lymphopenia, anemia, eosinophilia, and thrombocytopenia. Levels of angiotensin-converting enzyme may be elevated in all granulomatous diseases—including sarcoidosis—but are not diagnostic.¹

The differential diagnoses for sarcoidosis include cutaneous TB, lichen planus, granuloma annulare, discoid lupus, plaque psoriasis, syphilis and leprosy, among others.

Cutaneous disease may remit without treatment. Systemic steroids are quite effective but are problematic for long-term use. Intralesional steroid injection of 2-5 mg/cc triamcinolone has been used to good effect. Topical steroids have been effective as well, albeit to a lesser extent. Systemic agents used to treat cutaneous sarcoidosis include methotrexate (Rheumatrex, Trexall) and the antimalarials chloroquine (Aralen) and hydroxychloroquine (Plaquenil, Quineprox).

Systemic corticosteroid use is indicated in acute systemic disease, especially in the presence of fever and weight loss, active eye disease, active pulmonary involvement, or other overt systemic manifestation.

Since TNF is an important cytokine in the formation of granulomas, TNF inhibitors have been reported to be effective in refractory disease.⁸ As of this writing, this treatment is under consideration for this particular patient, since his disease has been resistant to all other commonly used medications.

Joe Monroe, PA-C, is a physician assistant specializing in dermatology at Dawkins Dermatology in Oklahoma City.

All electronic documents accessed July 15, 2012.