Bronchiectasis is associated with delayed diagnosis and adverse outcomes in the New Zealand Common Variable Immunodeficiency Disorders cohort study

Common variable immunodeficiency disorders (CVID) are multi-system disorders where target organ damage is mediated by infective, autoimmune and inflammatory processes. Bronchiectasis is probably the most common disabling complication of CVID. The risk factors for bronchiectasis in CVID patients are incompletely understood. The New Zealand CVID study (NZCS) is a nationwide longitudinal observational study of adults, which commenced in 2006. In this analysis, the prevalence and risk factors for bronchiectasis were examined in the NZCS. After informed consent, clinical and demographic data were obtained with an interviewer-assisted questionnaire. Linked electronic clinical records and laboratory results were also reviewed. Statistical methods were applied to determine if variables such as early-onset disease, delay in diagnosis and increased numbers of infections were associated with greater risk of bronchiectasis. One hundred and seven adult patients with a diagnosis of CVID are currently enrolled in the NZCS, comprising approximately 70% of patients known to have CVID in New Zealand. Fifty patients (46·7%) had radiologically proven bronchiectasis. This study has shown that patients with compared to those without bronchiectasis have an increased mortality at a younger age. CVID patients with bronchiectasis had a greater number of severe infections consequent to early-onset disease and delayed diagnosis. Indigenous Māori have a high prevalence of CVID and a much greater burden of bronchiectasis compared to New Zealand Europeans. Diagnostic latency has not improved during the study period. Exposure to large numbers of infections because of early-onset disease and delayed diagnosis was associated with an increased risk of bronchiectasis. Earlier diagnosis and treatment of CVID may reduce the risk of bronchiectasis and premature death in some patients.

Transient hypogammaglobulinaemia of infancy: many patients recover in adolescence and adulthood

Transient hypogammaglobulinaemia of infancy (THI) is a relatively rare disorder where there is an exaggeration of the physiological nadir of immunoglobulin (Ig)G between loss of transplacentally acquired maternal IgG and production by the infant. Patients may be vulnerable to infections during the period of hypogammaglobulinaemia. The precise time to recovery in all infants is currently unknown. We sought to determine the clinical features and time-course of recovery for patients with THI. We reviewed our experience with THI over the last three decades in order to describe clinical and laboratory features, as well as the time-course of recovery. Forty-seven patients were identified with THI. Only thirty-seven per cent remitted by 4 years of age, while some patients did not recover until the third or fourth decade. In keeping with previous studies, the majority (25 of 47) presented with recurrent infections, nine had a family history of immunodeficiency and 13 had adverse reactions to food as their dominant clinical manifestation. Chronic tonsillitis developed in 10 patients and symptoms improved following surgery. The group with food allergies recovered sooner than those presenting with infections or with a family history immunodeficiency. Eight patients failed to respond to at least one routine childhood vaccine. Two have IgA deficiency and four individuals recovering in adolescence and adulthood continue to have borderline/low IgG levels. None have progressed to common variable immunodeficiency disorders (CVID). THI is a misnomer, as the majority do not recover in infancy. Recovery from THI can extend into adulthood. THI must be considered in the differential diagnosis of adolescents or young adults presenting with primary hypogammaglobulinemia.

New diagnostic criteria for common variable immune deficiency (CVID), which may assist with decisions to treat with intravenous or subcutaneous immunoglobulin

Common variable immune deficiency (CVID) is the most frequent symptomatic primary immune deficiency in adults. The standard of care is intravenous immunoglobulin (IVIG) or subcutaneous immunoglobulin (scIG) therapy. The cause of CVID is currently unknown, and there is no universally accepted definition of CVID. This creates problems in determining which patients will benefit from IVIG/scIG treatment. In this paper, we review the difficulties with the commonly used European Society of Immune Deficiencies (ESID) and the Pan American Group for Immune Deficiency (PAGID) definition of CVID. We propose new criteria for the diagnosis of CVID, which are based on recent scientific discoveries. Improved diagnostic precision will assist with treatment decisions including IVIG/scIG replacement. We suggest that asymptomatic patients with mild hypogammaglobulinaemia are termed hypogammaglobulinaemia of uncertain significance (HGUS). These patients require long-term follow-up, as some will evolve into CVID.

Variability of memory B cell markers in a cohort of common variable immune deficiency patients over 6 months

Common Variable Immunodeficiency Disorder (CVID) is a complex disorder that predisposes patients to recurrent and severe infections. Immunophenotypic classification schemes were developed to categorize patients with CVID into phenotypic and prognostic groups based on different memory B cell subsets. Whether the B cell subset analysis is stable over time has not been investigated. B cell phenotyping in patients with CVID (n = 15) and sex- and age-matched controls (n = 26) were carried out according to the three B cell classifications. Patients with CVID were evaluated monthly over 6 months. Controls were assessed once during the study. We scored how often each patient was assigned to the same group within each classification. The Freiburg classification assigned patients to the same group at a rate of 73% and the Paris classification at 88%. The EUROclass classification of smB- versus smB+ was at 90%. The two subclassifications [(smB-21low or smB-21norm) and transitional B] were at 87% and 97%, respectively. The level of naïve B cells measured in all patients with CVID during the 6-month evaluation was the most stable B cell subset. We conclude that all classifications systems show considerable variability, but the EUROclass classification was the most reliable scheme for our 15 CVID and 26 healthy cohorts. Our results indicate that phenotypic classifications within CVID will be difficult while there is variability of commonly used assays.

Follicular lymphoma in a X-linked lymphoproliferative syndrome carrier female

X-linked lymphoproliferative (XLP) syndrome is a rare primary immune-deficiency disorder caused by mutations of the SH2D1A or XIAP genes. Males with the disorder are usually in good health until contracting Epstein-Barr virus (EBV) whereupon the majority of patients die from fulminant infectious mononucleosis, lymphoma or hypogammaglobulinaemia. This report describes a female carrier with an XLP phenotype who was retrospectively identified after her grandson died from the disorder. Subsequent genetic testing identified the patient's mother and affected maternal grandmother as XLP carriers. The family's medical records were significant. The proband had lymphoma at ages 2 and 8 and made a full recovery following treatment. Both the maternal grandmother and uncle died of non-Hodgkin's lymphoma. We were concerned that the XLP carrier mother may be predisposed to lymphoma if the normal X chromosome is skewed towards inactivation. The human androgen receptor assay detected random X chromosome inactivation in the carrier mother. EBV was not detected in the lymphoma tissues of the proband and his grandmother, confirming previous findings that EBV is not always associated with lymphoma in XLP. More significantly, our study highlights the importance of identifying XLP in families with a high incidence of lymphoma.

Antiphospholipid antibodies bind to activated but not resting endothelial cells: is an independent triggering event required to induce antiphospholipid antibody-mediated disease?

INTRODUCTION

Antiphospholipid antibodies (aPL) cause thrombotic disease and recurrent pregnancy loss. Despite their name it is now clear that the antigen for most antiphospholipid antibodies is the phospholipid-binding protein beta(2) glycoprotein I (beta(2)GPI). However, beta(2) glycoprotein I is only antigenic for antiphospholipid antibodies when the protein is immobilised on a suitable surface such as phosphatidyl serine. It has been suggested that antiphospholipid antibodies bind to beta(2) glycoprotein I on the surface of resting endothelial cells and this in turn leads to endothelial activation and the initiation of thrombosis. However, as phosphatidyl serine is absent from resting endothelial cell membranes, we questioned this hypothesis.

MATERIALS AND METHODS

The ability of human antiphospholipid antibody-containing sera and monoclonal antiphospholipid antibodies to interact with endothelial cells was examined using cell-based ELISAs employing human umbilical vein endothelial cells (HUVECs) as the antigen. The expression of adhesion molecules in response to treatment with antiphospholipid antibodies was also measured by a cell-based ELISA. Activation of NF kappa beta was examined using electrophoretic mobility shift assays (EMSAs).

RESULTS

Neither monoclonal antiphospholipid antibodies nor human sera containing antiphospholipid antibodies bound to resting endothelial cells. In contrast, one monoclonal antiphospholipid antibody did bind to both activated and apoptotic endothelial cells.

CONCLUSIONS

Antiphospholipid antibodies do not bind to resting endothelial cells nor do antiphospholipid antibodies activate resting endothelial cells. Rather, an independent triggering event is required to activate endothelial cells and subsequently some antiphospholipid antibodies may then bind to the activated endothelial cells and initiate a thrombogenic process.

NF-kappa B activation in vivo in both host and tumour cells by the antivascular agent 5,6-dimethylxanthenone-4-acetic acid (DMXAA)

5,6-Dimethylxanthenone-4-acetic acid (DMXAA), a new anticancer agent developed in this centre, has an antivascular action and causes regression of transplantable murine tumours that is mediated partially by the intratumoral production of tumour necrosis factor (TNF). DMXAA activates the nuclear factor-kappaB (NF-kappaB) transcription factor, which is involved in TNF synthesis and has also been suggested to mediate resistance to TNF. We wished to determine whether tumour cell NF-kappaB activation modulated the in vitro and in vivo effects of DMXAA. We compared the response of the 70Z/3 pre-B lymphoma cell line with that of its mutant 1.3E2 sub-line, which has a defective gamma-subunit of IKK, the kinase that phosphorylates IkappaB leading to NF-kappaB activation. As shown by electrophoretic mobility shift assays (EMSAs), DMXAA induced in vitro translocation of NF-kappaB (p50 and p65 subunits) into the nucleus of 70Z/3 cells, but not of 1.3E2 cells. However, when the cell lines were then grown as subcutaneous tumours in mice and treated with DMXAA (25 mg/kg), activation of NF-kappaB was found in nuclear extracts prepared from both 70/Z3 and 1.3E2 tumours, as well as from Colon 38 tumours that were used for comparison. This suggests that DMXAA induces NF-kappaB responses in host components of the tumour. Tumours grown from both 70Z/3 and 1.3E2 cells were found to regress completely following DMXAA treatment. Thus, the antitumour action of DMXAA appears to be independent of the ability of the target tumour cell population to induce NF-kappaB expression. Moreover, activation of NF-kappaB in the tumour cell did not confer resistance to DMXAA-induced therapy.