title: Biochemical and histochemical changes pertaining to active and healed cutaneous tuberculosis.
abstract: BACKGROUND
  Fibrosis is one of the major causes of post-treatment morbidity in tuberculosis. The molecular basis of fibrosis in active and healed tuberculous lesions is yet to be fully characterized.
  
  
  OBJECTIVE
  To measure the tissue levels of collagen, elastin, fibronectin, transforming growth factor-beta (TGF-beta) and zinc in active and healed lesions of cutaneous tuberculosis.
  
  
  METHODS
  Biopsy lesions obtained from 17 patients with active cutaneous tuberculosis and 12 patients after a 6-month regimen of antituberculous chemotherapy were examined. Collagen, elastin and zinc were estimated biochemically. In addition, the presence of collagen IV, TGF-beta and fibronectin were determined immunohistochemically.
  
  
  RESULTS
  It was found that collagen, elastin, fibronectin and TGF-beta levels were higher in the active lesions. The levels of zinc were similar in both active and healed lesions. Clinically, scar tissue or keloid formation was not seen in any of the healed lesions.
  
  
  CONCLUSIONS
  Effective antituberculous chemotherapy will lead to a substantial reduction of fibrosis and the consequent disability that can arise in patients with tuberculosis.
authors.affiliation: Department of Biochemistry, Tuberculosis Research Centre, Indian Council of Medical Research, Mayor V.R.Ramanathan Saalai, Chetpet, Chennai 31, 600 031, India.
authors.forename: K
authors.initials: K
authors.lastname: Jayasankar
authors.forename: H
authors.initials: H
authors.lastname: Shakila
authors.forename: K C
authors.initials: KC
authors.lastname: Umapathy
authors.forename: V D
authors.initials: VD
authors.lastname: Ramanathan
mesh_terms: D000995:Antitubercular Agents / Q000627:therapeutic use; D001706:Biopsy / Q000379:methods; D003094:Collagen / Q000032:analysis; D004549:Elastin / Q000032:analysis; D005353:Fibronectins / Q000032:analysis; D005355:Fibrosis; D006801:Humans; D007150:Immunohistochemistry / Q000379:methods; D007538:Isoniazid / Q000627:therapeutic use; D012293:Rifampin / Q000627:therapeutic use; D016212:Transforming Growth Factor beta / Q000032:analysis; D014382:Tuberculosis, Cutaneous / Q000188:drug therapy / Q000473:pathology*; D015032:Zinc / Q000032:analysis
chemical_list: D000995:Antitubercular Agents; D005353:Fibronectins; D016212:Transforming Growth Factor beta; D003094:Collagen; D004549:Elastin; D015032:Zinc; D007538:Isoniazid; D012293:Rifampin