title: Follicular bronchiolitis in surgical lung biopsies: clinical implications in 12 patients.
abstract: BACKGROUND
  Follicular bronchiolitis is a histopathologic finding that occurs in diverse clinical contexts. The current study was conducted to characterize clinico-radiologic features, and assess outcomes associated with follicular bronchiolitis.
  
  
  METHODS
  Twelve subjects with follicular bronchiolitis on lung biopsy were seen over a 9-year period, between 1996 and 2005. Medical records, biopsy and radiographic findings, and details of outcome at the time of last follow-up were recorded.
  
  
  RESULTS
  The study population included 4 men and 8 women; the median age at diagnosis was 54 years (range, 33-81 years). Four patients had underlying systemic diseases that included: 2 with common variable immunodeficiency, 1 Sjögren's syndrome and 1 undifferentiated connective tissue disease. The diagnosis was obtained by surgical lung biopsy in all cases. Follicular bronchiolitis was the major histologic pattern in 9 patients; organizing pneumonia, nonspecific interstitial pneumonia and usual interstitial pneumonia was seen in 1 patient each with follicular bronchiolitis being an associated secondary histopathologic component. Computed tomographic findings included reticular opacities, small nodules and ground-glass opacities. Clinical course was characterized by relative stability with partial response to immunosuppressive agents. During a median follow-up period of 47 months, only one death occurred--out of 9 patients where the outcome information was available--and was unrelated to lung disease.
  
  
  CONCLUSIONS
  The histologic lesion of follicular bronchiolitis may be seen as the predominant finding or a relatively minor feature in interstitial pneumonias. The clinical course and prognosis for most patients with follicular bronchiolitis is relatively good, and progressive lung disease is uncommon.
authors.affiliation: Division of Pulmonary and Critical Care Medicine, Desk East 18, Mayo Clinic, 200 1st St. SW, Rochester, MN, USA.
authors.forename: Michelle R
authors.initials: MR
authors.lastname: Aerni
authors.forename: Robert
authors.initials: R
authors.lastname: Vassallo
authors.forename: Jeffrey L
authors.initials: JL
authors.lastname: Myers
authors.forename: Rebecca M
authors.initials: RM
authors.lastname: Lindell
authors.forename: Jay H
authors.initials: JH
authors.lastname: Ryu
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001706:Biopsy; D001988:Bronchiolitis / Q000000981:diagnostic imaging / Q000473:pathology* / Q000503:physiopathology; D005260:Female; D005541:Forced Expiratory Volume; D006801:Humans; D008168:Lung / Q000000981:diagnostic imaging / Q000473:pathology*; D008297:Male; D008875:Middle Aged; D011859:Radiography; D014797:Vital Capacity