Pôster:

Cutaneous lesions are uncommon manifestations of tuberculosis, occurring in only 1 to 2 percent of infected patients. It can occurs by different ways: exogenous inoculation; contiguity (eg tuberculosis cutis orificialis) or by hematogenous spread. Tuberculids are a separate category of cutaneous tuberculosis that likely represent hypersensitivity reactions to mycobacterial antigens. Three types of tuberculids are described, including erythema induratum of Bazin, papulonecrotic tuberculid and lichen scrofulosorum. In contrast, cutaneous manifestations of sarcoidosis are more frequent, affecting about 25% of patients. Different patterns of lesions are described, among them papular sarcoidosis is one of the most common, usually presenting as numerous, non scaly, 1 to 10 mm papules, frequently on face with a predilection for the eylids and nasolabial folds.

Case report

A 41-year-old woman was admitted to investigate a two year history of weight loss, polyarthralgia and intermittent fever. After 1 year of initial symptoms, she evolved with generalized lymphadenopathy and face papular lesions predominantly in eyelids. Despite a strongly positive tuberculin skin test, laboratory exams were unremarkable. Chest and abdomen tomography evidenced nonspecific enlarged lymph nodes. Considering the chronic nature of her signs and symptoms, as well as the pattern of the papular lesions, sarcoidosis was suspected. The patient was submitted to cutaneous and submandibular lymph node biopsy, both of which revealed a chronic granulomatous inflammatory process with caseous necrosis suggestive of tuberculosis. The patient was discharged with the tuberculostatic therapy with clinical satisfactory response.

Conclusion

Tuberculosis and sarcoidosis are granulomatous multisystem diseases that share similar clinical and histological features, making the differential diagnosis between them a challenge at the bedside. Although cutaneous papules are more common in patients with sarcoidosis, some points of the case aided in the diagnosis of tuberculosis, including the presence of prolonged fever and a strong tuberculin skin test, both of which are uncommon in this sarcoid disease. In addition, the histological study was fundamental for the definitive diagnosis since, in an appropriate clinical context, the presence of granuloma with caseous necrosis is sufficient to define the treatment for tuberculosis.