Un tableau de bronchiolite révélant une pneumocystose pulmonaire lié Ã un déficit en HLA de classe II

The lack of MHC class II expression results in a severe defect in both humoral and cellular immune responses to foreign antigens. It is characterised by recurrent bronchopulmonary infections and chronic diarrhoea. The clinical onset occurs within the first months of life. Prognosis is very poor when bone marrow transplantation cannot be performed.