Association of minimal rejection in lung transplant recipients with obliterative bronchiolitis.

The clinical significance of minimal acute rejection (grade A1) in lung transplant recipients is unknown. We prospectively analyzed 1,159 transbronchial lung biopsies in 184 patients. Two hundred seventy-nine biopsies in 128 participants confirmed A1 histology at a mean postoperative day of 229 +/- 340. Sixty four of 255 surveillance A1 lesions progressed to high-grade acute rejection by 3 months of follow-up, whereas 40 developed new lymphocytic bronchiolitis. Twenty-four A1 biopsies were symptomatic, with only two cases progressing to high-grade rejection after steroid therapy. Seventy-eight of 184 patients experienced multiple (> or = 2) A1 biopsies in the first 12 months after transplant. Bronchiolitis obliterans syndrome developed in 68% of patients with multiple A1 lesions at a mean of 599 +/- 435 days, compared with 43% of patients with one or less A1 lesions at a mean of 819 +/- 526 (p = 0.022). Eighteen patients experienced multiple A1 biopsies after transplant in the absence of high-grade rejection episodes yet also developed earlier obliterative bronchiolitis (456 +/- 245 days, p = 0.020). We conclude that for A1 transbronchial lung biopsies, the conventional treatment of observation only is now challenged even in patients who are asymptomatic. Patients who experience multiple A1 lesions develop an earlier onset of obliterative bronchiolitis and may warrant alternative immunosuppressive strategies.

Prospective analysis of 1,235 transbronchial lung biopsies in lung transplant recipients.

OBJECTIVE: Fiber-optic bronchoscopy with multiple transbronchial lung biopsies (TBB) is the gold standard of evaluation of the pulmonary allograft post-lung transplantation (LT). However, controversy exists regarding the need for surveillance procedures and number of biopsy specimens required for satisfactory yield. The potential morbidity in obtaining multiple TBB specimens remains poorly described. We report the largest series of TBB in LT recipients to date, highlighting the occurrence of acute rejection and infection for surveillance and diagnostic procedures. The safety of TBB is analyzed and a biopsy schedule proposed. METHODS: Prospective analysis of 1,235 TBB in 230 LT recipients performed at St Vincent's Hospital from January 1995 to June 2000. RESULTS: Eight hundred thirty-six (67.7%) TBB were performed as surveillance and 399 (32.3%) for a clinical indication. No significant acute rejection (AR) or infection was disclosed in 53.3% of procedures. The Lung Rejection Study Group requirement of at least five pieces of evaluable lung parenchyma was achieved in 98.2% of procedures. The average number of evaluable fragments per procedure was 6.4, whereas only 3 TBB (0.24%) contained no lung parenchyma and 44 (3.6%) no bronchial wall. Histologic features of AR, lymphocytic bronchiolitis or infection were found in 18.9% of surveillance and 86.4% of clinical TBBs. The yield of surveillance procedures between 4 and 12 months was just 1.1% for cytomegalovirus and 6.1% for AR. The overall complication rate was 6.35% with no deaths recorded. CONCLUSION: Taking 10 to 12 TBB specimens has a high diagnostic yield and rarely fails to provide adequate tissue. The role of surveillance procedures post-lung transplantation remains controversial.