Cytomegalovirus in primary immunodeficiency

Evaluation of Inborn Errors of Immunity Among Patients with Opportunistic Pulmonary Infection

This review of immunocompromised host pneumonia as the result of inborn errors of immunity (IEI) is organized by opportunistic pulmonary pathogen. The authors identify patients who warrant an evaluation for an IEI based on their clinical presentation. Their recommendations are guided by the immune defect(s) associated with each opportunistic pulmonary infection. Physicians without expertise in immunology may begin an evaluation for IEI using the guidance provided here. Comprehensive evaluation by an immunologist may also be warranted in many instances.

High occurrence of autoimmune and lymphoproliferative manifestations in adults with common variable immunodeficiency in southern Taiwan

There are no reported case series of common variable immunodeficiency (CVID) from southern Taiwan. A 20-year review was performed in adult CVID from a southern Taiwan medical center. Patients with ages of 18 years or older were enrolled from May, 2003 to April, 2023. Twelve patients were identified, 8 females/4 males aged 23 to 68 (38.9 ± 13.4) with one to 11 years (5.0 ± 3.3) delay of diagnosis after disease onset. There were concomitant autoimmune disorders in 7 (58 %), splenomegaly in 10 (83 %), lymphadenopathy in 4 (25 %) and B-cell lymphoma in 2 (17 %). All received intravenous immunoglobulin (IVIg) infusion with improved autoimmune-mediated arthritis in 2. Patients with higher IgG trough levels (above 500 mg/dL) had a better survival than those with lower IgG trough levels. Adult CVID in southern Taiwan has a high occurrence of autoimmune and lymphoproliferative manifestations. Early diagnosis with IVIg infusion might improve the presentations.

Decreased T-cell response against latent cytomegalovirus infection does not correlate with anti-IFN autoantibodies in patients with APECED

Autoimmune polyendocrinopathy-candidiasis-ectodermal dystrophy (APECED) is an inborn error of immunity affecting both multiple endocrine organs and susceptibility to candidiasis, each with an autoimmune basis. Recently, high titer neutralizing anti-type I interferon (IFN) autoantibodies have been linked with increased severity of SARS-CoV-2 and varicella zoster virus infections in APECED patients. Examining immunity against cytomegalovirus (CMV), we found a higher prevalence of anti-CMV IgG antibodies in patients with APECED (N = 19) than in 44 healthy controls (90% vs 64%, p = 0.04); the similar difference in their IgG levels did not achieve significance (95 ± 74 vs 64 ± 35 IU/mL, ns.). In contrast, the frequency of CMV-specific T cells was lower (804 ± 718/million vs 1591 ± 972/million PBMC p = 0.03). We saw no correlations between levels of anti-CMV IgG and anti-IFN antibodies in APECED patients or in a separate cohort of patients with thymoma (n = 70), over 60% of whom also had anti-IFN antibodies. Our results suggest a dysregulated response to CMV in APECED patients and highlight immunodeficiency to viral infections as part of the disease spectrum.

Ophthalmic Complications, Diagnosis, and Treatment of Congenital Human Cytomegalovirus Infection

Background: Human cytomegalovirus (hCMV) is the most common etiological agent of congenital infections seen in newborns. Among the most commonly observed complications in children with congenital human cytomegalovirus infection are those affecting the visual system. Ocular complications of congenital CMV (cCMV) are a topic rarely addressed in the literature, which prompted the authors to update the available knowledge with the latest data. Methodology: English-language literature published between April 2000 and November 2023 (PubMed, NIH, Google Scholar) was analyzed for ocular complications of cCMV. The data obtained were categorized according to the ocular area involved and the incidence. A compilation of criteria for the symptomatic form of cCMV was also created. Results: The cCMV complications described in the literature affect all parts of the visual system: the anterior segment, the posterior segment, the posterior visual pathways, and the visual cortex. The most commonly described ocular complication of cCMV is choroidal and retinal scarring. Conclusions: Ophthalmic complications of cCMV can cause severe visual disturbances. Ophthalmic diagnosis in newborns should include hCMV PCR testing, which has the highest sensitivity and specificity. In the symptomatic form of cCMV, treatment should be instituted according to recommendations. A consensus should be established for screening of primary hCMV infection in pregnant women, the way in which to define the symptomatic form of cCMV, and the appropriateness and standards of treatment for primary hCMV infection in pregnant women.

Evaluation of Frequency of CMV Replication and Disease Complications Reveals New Cellular Defects and a Time Dependent Pattern in CVID Patients

PURPOSE

Common Variable Immunodeficiency (CVID) is characterized by hypogammaglobulinemia and failure of specific antibody production due to B-cell defects. However, studies have documented various T-cell abnormalities, potentially linked to viral complications. The frequency of Cytomegalovirus (CMV) replication in CVID cohorts is poorly studied. To address this gap in knowledge, we set up an observational study with the objectives of identifying CVID patients with active viraemia (CMV, Epstein-Barr virus (EBV)), evaluating potential correlations with immunophenotypic characteristics, clinical outcome, and the dynamic progression of clinical phenotypes over time.

METHODS

31 CVID patients were retrospectively analysed according to viraemia, clinical and immunologic characteristics. 21 patients with non CVID humoral immunodeficiency were also evaluated as control.

RESULTS

Active viral replication of CMV and/or EBV was observed in 25% of all patients. CMV replication was detected only in CVID patients (16%). CVID patients with active viral replication showed reduced HLA-DR+ NK counts when compared with CMV-DNA negative CVID patients. Viraemic patients had lower counts of LIN-DNAMbright and LIN-CD16+ inflammatory lymphoid precursors which correlated with NK-cell subsets. Analysis of the dynamic progression of CVID clinical phenotypes over time, showed that the initial infectious phenotype progressed to complicated phenotypes with time. All CMV viraemic patients had complicated disease.

CONCLUSION

Taken together, an impaired production of inflammatory precursors and NK activation is present in CVID patients with active viraemia. Since "Complicated" CVID occurs as a function of disease duration, there is need for an accurate evaluation of this aspect to improve classification and clinical management of CVID patients.

Possible Role of Cytomegalovirus in Gastric Cancer Development and Recurrent Macrolide-Resistant Campylobacter jejuni Infection in Common Variable Immunodeficiency: A Case Report and Literature Discussion

Common variable immunodeficiency (CVID) is the most common symptomatic immunodeficiency in adults. It comprises a group of syndromes whose etiology involves genetic, epigenetic, microbiota, and environmental factors. We present the case of a 46-year-old Caucasian male patient with CVID and an immune dysregulation phenotype. The particular elements of the case consisted of an atypical clinical course, which undoubtedly demonstrates the great variability of clinical manifestations that these types of patients can suffer from, including bacterial and viral infections, autoimmune phenomena, and neoplasia. Notably, the patient suffered from recurrent gastrointestinal infection with macrolide-resistant Campylobacter jejuni and gastroduodenal disease and viraemia by cytomegalovirus (CMV). In addition, CMV was postulated as the main pro-oncogenic factor contributing to the development of early-onset intestinal-type gastric adenocarcinoma, for which the patient underwent gastrectomy. The patient's evolution was difficult, but finally, as a result of the multidisciplinary approach, clinical stabilization and improvement in his quality of life were achieved. Based on our brief literature review, this is the first reported case of this clinical complexity. Our experience could help with the management of future patients with CVID and may also update current epidemiological data on CVID.

Cytomegalovirus drives Vδ1+ γδ T cell expansion and clonality in common variable immunodeficiency

The function and phenotype of γδ T cells in the context of common variable immunodeficiency (CVID) has not been explored. CVID is a primary immunodeficiency disorder characterized by impaired antibody responses resulting in increased susceptibility to infections. γδ T cells are a subset of unconventional T cells that play crucial roles in host defence against infections. In this study, we aim to determine the roles and functions of γδ T cells in CVID. We observe a higher frequency of Vδ1+ γδ T cells compared to healthy controls, particularly in older patients. We also find a higher proportion of effector-memory Vδ1+ γδ T cells and a more clonal T cell receptor (TCR) repertoire in CVID. The most significant driver of the Vδ1+ γδ T cell expansion and phenotype in CVID patients is persistent cytomegalovirus (CMV) viremia. These findings provide valuable insights into γδ T cell biology and their contribution to immune defence in CVID.

Characterization of infectious and non-infectious gastrointestinal disease in common variable immunodeficiency: analysis of 114 patient cohort

Common Variable Immunodeficiency (CVID), a complex primary immunodeficiency syndrome defined by defective B cell responses to infection and vaccination, has heterogeneous clinical manifestations. Gastrointestinal (GI) complications in CVID, both infectious and non-infectious, can cause significant impairment leading to malabsorption and frank malnutrition. In order to better characterize the spectrum of GI disease associated with CVID, we describe 114 patients with GI disease (15.6%) from our 728 patient single center CVID cohort. Norovirus, Giardia and Cytomegalovirus were the most frequently isolated infectious pathogens. CVID enteropathy was the most encountered GI diagnosis based on endoscopy, with only a minority of patients having Crohn's disease (6.1%) or ulcerative colitis/proctitis (4.5%). Concurrent autoimmunity (30.7%), lung disease (18.4%) and malignancy (8.7%) were also present in significant proportion of subjects. Lastly, 16 of 47 (34%) who underwent whole exome sequencing demonstrated a culprit gene defect associated with CVID.

The Middle East and North Africa Diagnosis and Management Guidelines for Inborn Errors of Immunity

Human inborn errors of immunity (IEI) are a group of 485 distinct genetic disorders affecting children and adults. Signs and symptoms of IEI are heterogeneous, and accurate diagnosis can be challenging and depends on the available human expertise and laboratory resources. The Middle East and North Africa (MENA) region has an increased prevalence of IEI because of the high rate of consanguinity with a predominance of autosomal recessive disorders. This area also exhibits more severe disease phenotypes compared with other regions, probably due to the delay in diagnosis. The MENA-IEI registry network has designed protocols and guidelines for the diagnosis and treatment of IEI, taking into consideration the variable regional expertise and resources. These guidelines are primarily meant to improve the care of patients within the region, but can also be followed in other regions with similar patient populations.

Case Report: Cytomegalovirus Disease Is an Under-Recognized Contributor to Morbidity and Mortality in Common Variable Immunodeficiency

Background

Common Variable Immunodeficiency (CVID) is classified as a ‘Predominantly Antibody Deficiency’ (PAD), but there is emerging evidence of cellular immunodeficiency in a subset of patients. This evidence includes CVID patients diagnosed with cytomegalovirus (CMV) infection, a hallmark of ‘combined immunodeficiency’. CMV infection also has the potential to drive immune dysregulation contributing to significant morbidity and mortality in CVID. We aim to determine the extent of cellular immune dysfunction in CVID patients, and whether this correlates with CMV infection status.

Methods

We conducted a single-center retrospective cohort study of individuals with CVID at the Royal Melbourne Hospital, and identified patients with and without CMV disease or viraemia. We then isolated T-cells from patient and healthy donor blood samples and examined T-cell proliferation and function.

Results

Six patients (7.6%, 6/79) had either CMV disease (pneumonitis or gastrointestinal disease), or symptomatic CMV viraemia. A high mortality rate in the cohort of patients with CVID and CMV disease was observed, with 4 deaths in the period of analysis (66.6%, 4/6). Individuals with CMV infection showed reduced T-cell division in response to T-cell receptor (TCR) stimulation when compared with CMV-negative patients.

Discussion

This study demonstrates the morbidity and mortality associated with CMV in CVID, and highlights the need for focused interventions for patients with CVID at risk of CMV disease.