[Common variable immunodeficiency: 17 observations in the adult]. / Le déficit immunitaire commun variable de l'adulte: étude clinique, biologique et immunologique chez 17 patients.

PURPOSE: Common variable immunodeficiency (CVID) is an immune defect characterized by primary hypogammaglobulinemia. Most of the time, clinical manifestations that reveal CVID are recurrent bacterial infections, but auto-immune or granulomatous events may occur. METHODS: This retrospective study was conducted on 17 patients fulfilling the classical CVID definition. Lymphocyte activation level was evaluated in 12 patients through HLA-DR expression on lymphocytes subsets. RESULTS: This study includes 17 patients, 7 men and 10 women. The mean age at the first clinical manifestation is 23 years and the mean age at diagnosis is 39 years. Recurrent upper and lower bacterial respiratory tract infections are common to all patients. Abdominal infection due to Mycobacterium avium-intracellulare complex is found in one patient. Digestive events are dominated by chronic diarrhea caused by giardiasis, nodular lymphoid hyperplasia or villous atrophy. Seven patients developed auto-immune conditions (insulin dependent diabetes, idiopathic thrombocytopenic purpura (ITP), rheumatoid arthritis) and 7 patients have a splenomegaly. Non caseating granulomas in the spleen or in lymph node biopsies are found in 3 patients. Ten patients have a T lymphopenia, 2 have a B lymphopenia, 5 have a CD4/CD8 ratio <1, and 6 have T CD4(+) lymphocytes <400/mm(3). The study of HLA-DR expression on lymphocytes subsets shows that 7/12 patients have activated T CD4(+) and/or CD8(+) cells and these patients have auto-immune or tumoral manifestations. The other 5 patients do not have activated T lymphocytes but present with infectious events only. CONCLUSIONS: Our study allows the separation of patients with CVID according to their T lymphocytes activation level. A patient's classification is necessary to define homogeneous groups of patients to perform genetic and functional studies which will probably reveal heterogeneous molecular abnormalities.

HLA-DR expression on lymphocyte subsets as a marker of disease activity in patients with systemic lupus erythematosus.

A major problem in the management of SLE patients is to predict a flare or to distinguish between active and quiescent disease. Serological markers are widely used to assess disease activity, but many patients have close to or normal values for these parameters while exhibiting obvious disease-related signs and symptoms. This study aimed to determine which serological parameters, among ESR, ANA and anti-dsDNA antibody titres, CH50 and the HLA-DR expression on circulating T-lymphocyte subsets, best reflected the development of SLE flares. Sixty SLE patients were included, 34 with quiescent disease throughout the entire follow-up period and 26 who experienced an SLE flare defined as having active disease. According to univariate analysis, all parameters were significantly higher for patients with active disease, with the percentage of CD8+DR+ cells being the most significant parameter (P = 10-7). Multivariate logistic regression analysis identified three independent variables enabling the identification of a lupus flare: CH50, the CD8+DR+ and CD4+DR+ cell percentages among total lymphocytes. The CD8+DR+ cell percentage is the biological parameter most significantly associated with a flare (P < 0.001), even more powerful than CH50 (P < 0.01). HLA-DR expression on CD8+ lymphocytes clearly coincided with disease evolution in seven patients enrolled as having quiescent disease, but who experienced one flare during follow-up that subsequently resolved. The percentage of circulating CD8+DR+ lymphocytes appears to be a biological marker which accurately reflects disease activity. A larger prospective study is needed to demonstrate the real efficacy of this marker in predicting an exacerbation in SLE patients.