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Post‐transplant air‐leak syndrome

A 51-year-old man relapsed with cervical lymphadenopathy 9 years after treatment for a transformed follicular lymphoma. He underwent salvage chemotherapy followed by a nonmyeloablative allogeneic stem cell transplant from his human leucocyte antigen-identical brother, after 2-Gray total body irradiation (TBI) and antithymocyte globulin. Unfortunately, the disease relapsed 10 months later. He subsequently received myeloablative doses of cyclophosphamide and 12-Gray TBI, followed by an allogeneic bone marrow transplant from a matched unrelated donor. Tacrolimus and methotrexate were used as graft-versus-host disease (GVHD) prophylaxis. The post-transplant course was complicated by pneumonitis and acute grade-III GVHD of the skin and gastrointestinal tract. Around day 50 post-transplant, he became dyspnoeic and hypoxaemic. Chest radiograph (CXR) revealed bilateral interstitial infiltrates. All investigations for infectious causes, including bronchoalveolar lavage, were negative. One week later, the dyspnoea worsened. Neck swelling developed, along with dysphonia, dysphagia and chest pain. CXR showed subcutaneous emphysema, cervical emphysema, pneumomediastinum and a tiny right pneumothorax (left). High-resolution computerized tomography of the chest showed diffuse reticulo-nodular infiltrates with multiple bullae, characteristic of bronchiolitis obliterans (right). One month after receiving treatment with increased immunosuppression, the air-leak syndrome and his oxygen requirement had improved considerably. Air-leak syndromes including pneumomediastinum, pneumothorax, pneumopericardium, subcutaneous emphysema and cervical emphysema may complicate severe bronchiolitis obliterans, a recognized manifestation of GVHD. Other possible causes of air-leak syndrome, such as aspergillosis and Pneumocystic carinii pneumonia, however, must be excluded. Therapy for this post-transplant complication involves an increase in immunosuppression, though this is often ineffective. Persistent air-leaks may also require pleurodesis or pleurectomy. Post-transplant bronchiolitis obliterans results in irreversible airway obstruction. The condition is usually progressive and fatal.