title: [Detection and identification of mycobacterial gene in skin lesions and lymph nodes in patients with sarcoidosis].
abstract: OBJECTIVE
  To investigate the possible role of mycobacteria in the pathogenesis of sarcoidosis.
  
  
  METHODS
  We used nested polymerase chain reaction-restriction fragment length polymorphism (nPCR-RFLP) and gene sequencing method to examine 31 formalin-fixed, paraffin-embedded specimens (including 19 skin lesions and 12 lymph nodes ) obtained from patients with sarcoidosis, 14 normal skin specimens, and 3 cutaneous tuberculosis specimens.
  
  
  RESULTS
  The 65kD mycobacterial heat shock protein gene was found in 4 out of 19 (21.1%) skin specimens of sarcoidosis. The mycobacteria included M. tuberculosis (n = 1), M. chelonei (n = 2), and M. gordonae (n = 1). Mycobacterial DNA was negative in 12 lymph node specimens and 14 normal skin specimens. M. tuberculosis gene was detected in all 3 specimens of cutaneous tuberculosis.
  
  
  CONCLUSIONS
  Mycobacteria may play a role in the pathogenesis of cutaneous sarcoidosis.
authors.affiliation: Department of Dermatology, Peking University People's Hospital, Beijing 100044, China.
authors.forename: Xiao-Lan
authors.initials: XL
authors.lastname: Ding
authors.forename: Lin
authors.initials: L
authors.lastname: Cai
authors.forename: Jian-Zhong
authors.initials: JZ
authors.lastname: Zhang