Bronchiolitis Obliterans Associated with Stevens-Johnson Syndrome and Response to Azathioprine

Abstract

To the Editor: Stevens-Johnson syndrome (SJS) is an acute, self-limiting, immune-complex mediated hypersensitivity disorder of skin and mucus membranes. Though acute pulmonary complications are well described, persistent pulmonary sequelae associated with SJS are rare [1]. We describe severe progressive form of bronchiolitis obliterans (BO) following SJS and good response to azathioprine. A 9-y-old boy developed SJS following oral ibuprofen prescribed for febrile illness. A week later, he developed persistent cough, wheezing and progressive respiratory distress. At admission, he had tachypnea, retractions, extensive wheezing and crepitations with hyperpigmented scars, cicatrical ectropion in the left eye and dystrophic changes in nails. Oxygen-saturation was 87 % in room-air. Pulmonary function test showed severe obstruction with no response to bronchodilators. Chest-radiograph and high-resolution computerized tomography were consistent with BO (Figs. 1 and 2). He received supplemental oxygen, β2-agonist and budesonide inhalations, chest-physiotherapy and prednisolone. Azithromycin three times a week was also added. At 2-mo follow-up, he had persistent cough, exertional dyspnea and wheeze for which azathioprine was added as a steroid sparing agent. At 1-year follow-up, the patient improved clinically and was able to do his daily activities at home. Oxygenation and PFT improved. Although, he had dyspnea on moderate exertion, intermittent cough with wheeze, the symptoms had not worsened and the disease appeared to be controlled. BO may occur within days after SJS even when the initial pulmonary involvement is not severe [1]. The association of non-steroidal anti-inflammatory drugs like ibuprofen with SJS is well known [2]. The findings of mosaic perfusion, vascular attenuation and central bronchiectasis onHRCTare diagnostic of BO obviating the need for lung-biopsy in a consistent clinical setting, as in index case [3]. The anti-inflammatory effects of corticosteroids justify their use in the early phases. We added immune-modulator azathioprine which suppresses lymphocyte proliferation and decreases CD8+ lymphocyte subpopulation, as a corticosteroid sparing agent for control of inflammation. Previous anaecdotal reports in adults have suggested that azathioprine might be useful as a corticosteroidsparing agent for the treatment of organizing pneumonia [4]. Moreover, drugs like mycophenolate mofetil and azathioprine have also been used for prevention of bronchiolitis obliterans