Common variable immunodeficiency: 20-yr experience at a single centre.

Common variable immunodeficiency (CVID) is the most common symptomatic primary immunodeficiency. It can present at any age in patients with a history of recurrent bacterial infections, with or without a family history of other primary immunodeficiencies (PID), and shows a wide range of clinical manifestations and immunological data. Diagnosis is based on low IgG, IgM and/or IgA levels. Delayed diagnosis and therapy can lead to bronchiectasis and malabsorption. The aim of this study was to describe a paediatric population diagnosed of CVID and its evolution in the population. Memory B-cell (MB) classification carried out in these patients was correlated with clinical manifestations and outcome. Clinical and immunological data of 22 CVID children under 18 yr treated at our centre between 1985 and 2005 are presented. Immunological studies included those for diagnosis and MB quantification. Differences in form of presentation, familial incidence and MB classification were reviewed. A statistical descriptive analysis was made. Infections were the commonest manifestation, affecting mainly respiratory (19/22) and gastrointestinal (10/22) tracts. Bronchiectasis was present in seven cases, and detected prior to CVID diagnosis in five. Replacement therapy led to a significant reduction in the number of infections. Severe complications appeared mostly in patients without MB. Patients of the same family share the same MB group. Family members had also been diagnosed of CVID in seven cases. Early diagnosis and therapy are essential to improve outcome in these patients. MB studies are useful in children to orient prognosis and further genetic studies.

An update on treatment strategies for common variable immunodeficiency.

Common variable immunodeficiency (CVID) is a primary immunological disease with variable severity, ranging from mild forms of infections to chronic progressive complications. The hallmark of this disorder is hypogammaglobulinemia due to an unknown molecular defect in immune regulation. The primary clinical manifestations are recurrent infections that may lead to structural damage of affected organs. Adequate intravenous immunoglobulin (Ig) therapy has dramatically changed the prognosis of this disorder, and the advent of home subcutaneous Ig therapy has further improved the quality of life of these patients. Aberrant T-cell functions predispose to autoimmune, inflammatory and lymphoproliferative complications, as well as malignancies in a variable percentage of CVID patients. Immunosuppressive anti-inflammatory therapies and chemotherapy are used, although always in conjunction with adequate replacement Ig therapy and adjunct antimicrobial prophylaxis. Any organ can be involved and therefore a multidisciplinary approach to the management of this disorder is essential.

The EUROclass trial: defining subgroups in common variable immunodeficiency.

The heterogeneity of common variable immunodeficiency (CVID) calls for a classification addressing pathogenic mechanisms as well as clinical relevance. This European multicenter trial was initiated to develop a consensus of 2 existing classification schemes based on flowcytometric B-cell phenotyping and the clinical course. The clinical evaluation of 303 patients with the established diagnosis of CVID demonstrated a significant coincidence of granulomatous disease, autoimmune cytopenia, and splenomegaly. Phenotyping of B-cell subpopulations confirmed a severe reduction of switched memory B cells in most of the patients that was associated with a higher risk for splenomegaly and granulomatous disease. An expansion of CD21(low) B cells marked patients with splenomegaly. Lymphadenopathy was significantly linked with transitional B-cell expansion. Based on these findings and pathogenic consideration of B-cell differentiation, we suggest an improved classification for CVID (EUROclass), separating patients with nearly absent B cells (less than 1%), severely reduced switched memory B cells (less than 2%), and expansion of transitional (more than 9%) or CD21(low) B cells (more than 10%). Whereas the first group contains all patients with severe defects of early B-cell differentiation, severely reduced switched memory B cells indicate a defective germinal center development as found in inducible constimulator (ICOS) or CD40L deficiency. The underlying defects of expanded transitional or CD21(low) B cells remain to be elucidated. This trial is re-gistered at http://www.uniklinik-freiburg.de/zks/live/uklregister/Oeffentlich.html as UKF000308.

Common variable immunodeficiency: association between memory B cells and lung diseases.

BACKGROUND: Malabsorption syndrome often develops in patients with common variable immunodeficiency (CVID). Why structural damages appear in some CVID patients and not in others is not fully understood. Memory B cells (MBs) are responsible for the production of specific antibodies, and their defects have previously been related to autoimmune, granulomatous, and lymphoproliferative complications of CVID. The objective of this study was to ascertain whether a relationship exists between MB defects and the clinical outcome of respiratory and intestinal involvement in these patients. METHODS: Forty-one CVID patients were grouped as follows, according to the quantification of peripheral MBs: the MB2 group (n = 7) included patients with normal MBs; the MB1 group (n = 16) included patients with low switched MBs; and the MB0 group (n = 18) included patients with absent/low MBs. The clinical outcome of respiratory and intestinal involvement of patients was then compared among the three groups. RESULTS: In the MB0 group, chronic lung disease (ie, bronchiectasis and diminished FVC and/or FEV1) developed in 50% of patients vs 13% in the MB1 group and 0% in the MB2 group (p < 0.05). In the MB0 group, malabsorption syndrome or chronic noninfectious diarrhea developed in 50% of patients vs 19% in the MB1 group and 0% in the MB2 group (p < 0.05). No differences were found among the three groups for age at onset of symptoms, delay in diagnosis/treatment, months of follow-up/treatment, and prediagnostic serum IgG concentration. CONCLUSIONS: Alterations in MB count appear to be associated with a severe clinical outcome of respiratory and intestinal involvement in CVID. The MB count could be a useful laboratory parameter for orienting the prognosis and management of CVID patients.