[Pulmonary hemosiderosis revealing class II HLA deficiency in a 9-month-old infant: a case report].

Pulmonary hemosiderosis is a rare and severe respiratory condition in children corresponding to chronic alveolar haemorrhage. Combined immune deficiencies are considered rare diseases, characterised by a quantitative or qualitative defect of T lymphocytes, associated or not with a complete or partial deficiency of immunoglobulin synthesis. We report a rare association of pulmonary hemosiderosis and class II HLA deficiency. Infant T, aged 9 months, was admitted for acute respiratory distress and pallor. The clinical examination found a marked mucocutaneous pallor, arterial oxygen saturation at 87%, a respiratory rate at 65 cycles/min, with diffuse crackling rales at both pulmonary hemifields. The blood count objectified with regenerative normocytic normochrome anemia and neutropenia. In addition, there was a CRP at 59 mg/l, a positive direct Coombs test, and a ferritin level elevated to 1095 ng/ml. Chest CT showed an aspect in favor of severe bilateral interstitial lung disease. The cytological study of bronchoalveolar lavage objectified a hemorrhagic fluid, with the cytological study siderophage at 46%, a positive Perls staining and a Gold score of 187. The immune assessment made it possible to make the diagnosis of combined immune deficiencies by HLA class II deficiency. T was put on antibiotic therapy, two blood cell transfusions, general corticosteroid therapy, nebulizations of salbutamol, Pulmicort, and an infusion of versatile immunoglobulins. The evolution was favorable. Treatment with allogeneic hematopoietic stem cell transplantation is ongoing. This observation recalls the importance of questioning the diagnosis of acute bronchiolitis, especially when the evolution seems atypical and unusual.