Background and purpose: Sarcoidosis is rare in Taiwan, although increasingly more cases are being diagnosed. The purpose of this study was to further characterize the clinical features of all biopsy-proven cases of sarcoidosis diagnosed between 1988 and 2002 in a national teaching hospital in southern Taiwan, and to detect mycobacterial DNA in sarcoid lesions.
Materials and methods: A total of 28 biopsy-proven cases of sarcoidosis were reviewed. Formalin-fixed, paraffin-embedded tissues were used as template for nested polymerase chain reaction (PCR) detection of the mycobacterial hsp65 gene. This was followed by direct DNA sequencing to identify the species in positive cases.
Results: Eleven males and 17 females, aged 19 to 79 years (mean, 50 yr) were enrolled. Bilateral hilar lymphadenopathy, pulmonary lesions or both, were detected in 14 patients (50%). Of the 22 patients (78%) with skin involvement, nine manifested angiolupoid lesions on the face, a rare form of cutaneous sarcoidosis. Eight patients had papular lesions and five had plaque lesions, usually widespread on the extremities and trunk. No patients presented with erythema nodosum. Fifteen of the 22 patients with skin involvement had had the disease for more than 2 years. The hsp65 gene was detected in seven cases, four of which showed greater than 90% homology to four different species of atypical mycobacteria.
Conclusion: Our study showed that sarcoidosis tended to affect women older than 40 years, often manifested angiolupoid lesions on the face, and ran a subacute to chronic course. Atypical mycobacteria might play a role in the etiology in a minority of our patients, but more cases and other potential etiologic agents need to be studied.