Overview
Lung transplant rejection involves immune-mediated damage to the transplanted lung, primarily manifesting as acute cellular rejection (ACR) and chronic rejection (e.g., bronchiolitis obliterans syndrome). Proper diagnosis and timely intervention are crucial to prevent graft loss 1.Diagnosis
Key Diagnostic Criteria: Histopathological examination of lung allograft biopsy specimens is essential.
Grading Systems: Utilize the ISHLT grading system (A, B, C) where:
- Grade A: No rejection
- Grade B: ACR (B0: minimal, B1R: mild, B2R: moderate, B3R: severe)
- Grade C: Chronic rejection (e.g., bronchiolitis obliterans)
Specific Findings: Lymphocytic bronchiolitis may be under-recognized as grade B rejection by some clinicians, potentially leading to under-treatment 1.Management
First-Line Treatments:
- Immunosuppression Adjustment: Increase or switch maintenance immunosuppression (e.g., tacrolimus, mycophenolate mofetil) 1.
Adjunctive Treatments:
- Intravenous Immunoglobulin (IVIG): Consider in refractory cases 1.
- Anti-thymocyte Globulin (ATG): Used in severe or refractory rejection 1.Special Populations
Pulmonologists' Practices Vary: There is variability in how pulmonologists interpret and treat lymphocytic bronchiolitis and active mononuclear inflammatory infiltrates in different patient groups, though specific guidance for pregnancy, pediatrics, elderly, or comorbidities is not detailed in the provided abstracts 1.Key Recommendations
Combine grades B1 and B2 rejection into B1R for treatment purposes in asymptomatic patients to ensure consistent management 1 (Evidence: Moderate).
Pathologists and pulmonologists should maintain consistent interpretation of lymphocytic bronchiolitis as grade B rejection to avoid under-treatment 1 (Evidence: Moderate).
Consider active mononuclear inflammatory infiltrate in bronchiolitis obliterans as a factor influencing treatment decisions, reflecting nuanced clinical judgment 1 (Evidence: Expert opinion).References
1 Gordon IO, Bhorade S, Vigneswaran WT, Garrity ER, Husain AN. SaLUTaRy: survey of lung transplant rejection. The Journal of heart and lung transplantation : the official publication of the International Society for Heart Transplantation 2012. link