Clinical implications of VUS reclassification in a single-centre series from application of ACMG/AMP classification rules specified for BRCA1/2.

BACKGROUND: BRCA1/2 testing is crucial to guide clinical decisions in patients with hereditary breast/ovarian cancer, but detection of variants of uncertain significance (VUSs) prevents proper management of carriers. The ENIGMA (Evidence-based Network for the Interpretation of Germline Mutant Alleles) BRCA1/2 Variant Curation Expert Panel (VCEP) has recently developed BRCA1/2 variant classification guidelines consistent with ClinGen processes, specified against the ACMG/AMP (American College of Medical Genetics and Genomics/Association for Molecular-Pathology) classification framework. METHODS: The ClinGen-approved BRCA1/2-specified ACMG/AMP classification guidelines were applied to BRCA1/2 VUSs identified from 2011 to 2022 in a series of patients, retrieving information from the VCEP documentation, public databases, literature and ENIGMA unpublished data. Then, we critically re-evaluated carrier families based on new results and checked consistency of updated classification with main sources for clinical interpretation of BRCA1/2 variants. RESULTS: Among 166 VUSs detected in 231 index cases, 135 (81.3%) found in 197 index cases were classified by applying BRCA1/2-specified ACMG/AMP criteria: 128 (94.8%) as Benign/Likely Benign and 7 (5.2%) as Pathogenic/Likely Pathogenic. The average time from the first report as 'VUS' to classification using this approach was 49.4 months. Considering that 15 of these variants found in 64 families had already been internally reclassified prior to this work, this study provided 121 new reclassifications among the 151 (80.1%) remaining VUSs, relevant to 133/167 (79.6%) families. CONCLUSIONS: These results demonstrated the effectiveness of new BRCA1/2 ACMG/AMP classification guidelines for VUS classification within a clinical cohort, and their important clinical impact. Furthermore, they suggested a cadence of no more than 3 years for regular review of VUSs, which however requires time, expertise and resources.

Decline of gastric cancer mortality in common variable immunodeficiency in the years 2018-2022.

Introduction: In patients with Common Variable Immunodeficiency, malignancy has been reported as the leading cause of death in adults, with a high risk of B-cell lymphomas and gastric cancer. Methods: We conducted a five-year prospective study aiming to update the incidence and mortality of gastric cancer and the incidence of gastric precancerous lesions in 512 CVID patients who underwent a total of 400 upper gastrointestinal endoscopies. Results: In the pre-pandemic period, 0.58 endoscopies were performed per patient/year and in the COVID-19 period, 0.39 endoscopies were performed per patient/year. Histology revealed areas with precancerous lesions in about a third of patients. Patients who had more than one gastroscopy during the study period were more likely to have precancerous lesions. Two patients received a diagnosis of gastric cancer in the absence of Helicobacter pylori infection. The overall prevalence of Helicobacter pylori infection in biopsy specimens was 19.8% and related only to active gastritis. Among patients who had repeated gastroscopies, about 20% progressed to precancerous lesions, mostly independent of Helicobacter pylori. Discussion: While gastric cancer accounted for one in five deaths from CVID in our previous survey, no gastric cancer deaths were recorded in the past five years, likely consistent with the decline in stomach cancer mortality observed in the general population. However, during the COVID-19 pandemic, cancer screening has been delayed. Whether such a delay or true decline could be the reason for the lack of gastric cancer detection seen in CVID may become clear in the coming years. Due to the high incidence of precancerous lesions, we cannot rely on observed and predicted trends in gastric cancer mortality and strongly recommend tailored surveillance programs.

Multi-Gene Next-Generation Sequencing Panel for Analysis of BRCA1/BRCA2 and Homologous Recombination Repair Genes Alterations Metastatic Castration-Resistant Prostate Cancer.

Despite significant therapeutic advances, metastatic CRPC (mCRPC) remains a lethal disease. Mutations in homologous recombination repair (HRR) genes are frequent in mCRPC, and tumors harboring these mutations are known to be sensitive to PARP inhibitors. The aim of this study was to verify the technical effectiveness of this panel in the analysis of mCRPC, the frequency and type of mutations in the BRCA1/BRCA2 genes, as well as in the homologous recombination repair (HRR) genes. A total of 50 mCRPC cases were analyzed using a multi-gene next-generation sequencing panel evaluating a total of 1360 amplicons in 24 HRR genes. Of the 50 cases, 23 specimens (46.0%) had an mCRPC harboring a pathogenic variant or a variant of uncertain significance (VUS), whereas in 27 mCRPCs (54.0%), no mutations were detected (wild-type tumors). BRCA2 was the most commonly mutated gene (14.0% of samples), followed by ATM (12.0%), and BRCA1 (6.0%). In conclusion, we have set up an NGS multi-gene panel that is capable of analyzing BRCA1/BRCA2 and HRR alterations in mCRPC. Moreover, our clinical algorithm is currently being used in clinical practice for the management of patients with mCRPC.

Case Report: Interindividual variability and possible role of heterozygous variants in a family with deficiency of adenosine deaminase 2: are all heterozygous born equals?

Deficiency of adenosine deaminase 2 (DADA2) is a rare systemic autoinflammatory disease, typically with autosomal recessive inheritance, usually caused by biallelic loss of function mutations in the ADA2 gene. The phenotypic spectrum is broad, generally including fever, early-onset vasculitis, stroke, and hematologic dysfunction. Heterozygous carriers may show related signs and symptoms, usually milder and at an older age. Here we describe the case of two relatives, the proband and his mother, bearing an ADA2 homozygous pathogenic variant, and a heterozygous son. The proband was a 17-year-old boy with intermittent fever, lymphadenopathies, and mild hypogammaglobulinemia. He also had sporadic episodes of aphthosis, livedo reticularis and abdominal pain. Hypogammaglobulinemia was documented when he was 10 years old, and symptoms appeared in his late adolescence. The mother demonstrated mild hypogammaglobulinemia, chronic pericarditis since she was 30 years old and two transient episodes of diplopia without lacunar lesions on MRI. ADA2 (NM_001282225.2) sequencing identified both mother and son as homozygous for the c.1358A>G, p.(Tyr453Cys) variant. ADA2 activity in the proband and the mother was 80-fold lower than in the controls. Clinical features in both patients improved on anti-tumor necrosis factor therapy. An older son was found to be heterozygous for the same mutation post-mortem. He died at the age of 12 years due to a clinical picture of fever, lymphadenitis, skin rash and hypogammaglobulinemia evolving toward fatal multiorgan failure. Biopsies of skin, lymph nodes, and bone marrow excluded lymphomas and vasculitis. Despite being suspected of symptomatic carrier, the contribution of an additional variant in compound heterozygosity, or further genetic could not be ruled out, due to poor quality of DNA samples available. In conclusion, this familiar case demonstrated the wide range of phenotypic variability in DADA2. The search for ADA2 mutations and the assessment of ADA2 activity should be considered also in patients with the association of hypogammaglobulinemia and inflammatory conditions, also with late presentation and in absence of vasculitis. Furthermore, the clinical picture of the deceased carrier suggests a possible contribution of heterozygous pathogenic variants to inflammation.

Characterization of BRCA Deficiency in Ovarian Cancer.

BRCA testing is recommended in all Ovarian Cancer (OC) patients, but the optimal approach is debated. The landscape of BRCA alterations was explored in 30 consecutive OC patients: 6 (20.0%) carried germline pathogenic variants, 1 (3.3%) a somatic mutation of BRCA2, 2 (6.7%) unclassified germline variants in BRCA1, and 5 (16.7%) hypermethylation of the BRCA1 promoter. Overall, 12 patients (40.0%) showed BRCA deficit (BD), due to inactivation of both alleles of either BRCA1 or BRCA2, while 18 (60.0%) had undetected/unclear BRCA deficit (BU). Regarding sequence changes, analysis performed on Formalin-Fixed-Paraffin-Embedded tissue through a validated diagnostic protocol showed 100% accuracy, compared with 96.3% for Snap-Frozen tissue and 77.8% for the pre-diagnostic Formalin-Fixed-Paraffin-Embedded protocol. BD tumors, compared to BU, showed a significantly higher rate of small genomic rearrangements. After a median follow-up of 60.3 months, the mean PFS was 54.9 ± 27.2 months in BD patients and 34.6 ± 26.7 months in BU patients (p = 0.055). The analysis of other cancer genes in BU patients identified a carrier of a pathogenic germline variant in RAD51C. Thus, BRCA sequencing alone may miss tumors potentially responsive to specific treatments (due to BRCA1 promoter methylation or mutations in other genes) while unvalidated FFPE approaches may yield false-positive results.

T-Cell Defects Associated to Lack of Spike-Specific Antibodies after BNT162b2 Full Immunization Followed by a Booster Dose in Patients with Common Variable Immune Deficiencies.

Following the third booster dose of the mRNA vaccine, Common Variable Immune Deficiencies (CVID) patients may not produce specific antibodies against the virus spike protein. The T-cell abnormalities associated with the absence of antibodies are still a matter of investigation. Spike-specific IgG and IgA, peripheral T cell subsets, CD40L and cytokine expression, and Spike-specific specific T-cells responses were evaluated in 47 CVID and 26 healthy donors after three doses of BNT162b2 vaccine. Testing was performed two weeks after the third vaccine dose. Thirty-six percent of the patients did not produce anti-SARS-CoV-2 IgG or IgA antibodies. Non responder patients had lower peripheral blood lymphocyte counts, circulating naïve and central memory T-cells, low CD40L expression on the CD4+CD45+RO+ and CD8+CD45+RO+ T-cells, high frequencies of TNFα and IFNγ expressing CD8+ T-cells, and defective release of IFNγ and TNFα following stimulation with Spike peptides. Non responders had a more complex disease phenotype, with higher frequencies of structural lung damage and autoimmunity, especially autoimmune cytopenia. Thirty-five percent of them developed a SARS-CoV-2 infection after immunization in comparison to twenty percent of CVID who responded to immunization with antibodies production. CVID-associated T cell abnormalities contributed to the absence of SARS-CoV-2 specific antibodies after full immunization.

Corrigendum: Case Report: Hodgkin Lymphoma and Refractory Systemic Lupus Erythematosus Unveil Activated Phosphoinositide 3-Kinase-δ Syndrome 2 in an Adult Patient.

[This corrects the article DOI: 10.3389/fped.2021.702546.].

Case Report: Hereditary Alpha Tryptasemia in Children: A Pediatric Case Series and a Brief Overview of Literature.

Hereditary alpha tryptasemia (HαT) is a recently described autosomal dominant genetic trait caused by an increased copy number of the TPSAB1 gene. It commonly leads to elevated basal serum tryptase levels, and it is associated with heterogeneous clinical manifestations. Some individuals report few to no symptoms, while others present with a spectrum of debilitating features. Most symptoms related to HαT may be explained by mast cell activation and mediator release, namely multiple allergies, anaphylaxis, and skin rash. However, the genotype-phenotype correlation has not yet been clearly understood. In particular, the characterization of the clinical spectrum lacks in children, where differential diagnosis could be challenging. Systemic mastocytosis, HαT, and mast cell activation syndrome are all associated with overlapping pathophysiology and symptoms, making the distinction between these conditions a difficult task. We herein describe two pediatric cases of HαT and their respective families at our tertiary care teaching hospital, highlighting the diagnostic workup and differential diagnosis. We also provide a brief review of the literature to underline the peculiar features of this condition in children.

Case Report: Hodgkin Lymphoma and Refractory Systemic Lupus Erythematosus Unveil Activated Phosphoinositide 3-Kinase-δ Syndrome 2 in an Adult Patient.

Introduction: Activated phosphoinositide 3-kinase-δ syndrome 2 (APDS2) is a rare primary immune regulatory disorder caused by heterozygous gain of function mutation in the PIK3R1 gene encoding PI3Kδ regulatory p85α subunit and resulting in PI3Kδ hyperactivation. Clinical features range from recurrent infections to manifestations of immune dysregulation like autoimmunity, inflammation, systemic lymphoproliferation, and increased risk of cancer. We describe a new dominant PIK3R1 mutation causing APDS2 presenting with lymphoma and systemic refractory autoimmunity. Case Presentation: A 30-year-old woman was referred to the Immunology Unit of our hospital for uncontrolled systemic lupus erythematosus, including chilblains lesions, systemic lymphoproliferation and IgA deficiency. At 19 years of age, she was diagnosed with Hodgkin's lymphoma. Subsequently, she presented systemic lupus erythematosus onset, with episodes of severe exacerbation, including autoimmune hemolytic anemia and pleuro-pericarditis. Initial clinical response to conventional treatments was reported. Immunological investigations performed during our first observation showed severe lymphopenia, IgA deficiency, elevated IgM with reduced IgG2 levels, and low vaccination antibody titers. Quantitative real-time polymerase chain reaction (PCR) assay for Cytomegalovirus and Epstein-Barr virus showed low viral loads for both viruses in serum. An increase of serum inflammatory markers highlighted persistent systemic hyperinflammation. The next-generation sequencing (NGS)-based gene panel tests for primary immunodeficiency showed a heterozygous A>G substitution in the splice acceptor site at c.1300-2 position of PIK3R1, leading to exon-skipping. Conclusion: This case emphasizes the importance of suspecting primary immune regulatory disorders in young adults, predominantly showing a severe, aggressive, and refractory to treatment immune dysregulation phenotype, even in the absence of major infectious diseases at the onset. Different treatments can be promptly started, and a delayed diagnosis can highly impact the outcome. Targeted therapy against PI3Kδ pathway defect effectively improves drug-resistant autoimmunity, lymphoproliferation, and risk of progression to malignancy; eligible patients could benefit from its use even as a bridge therapy to transplantation, currently the only definitive curative treatment. Therefore, identifying genetic mutation and prompt targeted treatment are essential to control disease manifestations, prevent long-term sequelae, and enable curative HSCT in APDS2 patients.

Detecting Variants in the NBN Gene While Testing for Hereditary Breast Cancer: What to Do Next?

The NBN gene has been included in breast cancer (BC) multigene panels based on early studies suggesting an increased BC risk for carriers, though not confirmed by recent research. To evaluate the impact of NBN analysis, we assessed the results of NBN sequencing in 116 BRCA-negative BC patients and reviewed the literature. Three patients (2.6%) carried potentially relevant variants: two, apparently unrelated, carried the frameshift variant c.156_157delTT and another one the c.628G>T variant. The latter was subsequently found in 4/1390 (0.3%) BC cases and 8/1580 (0.5%) controls in an independent sample, which, together with in silico predictions, provided evidence against its pathogenicity. Conversely, the rare c.156_157delTT variant was absent in the case-control set; moreover, a 50% reduction of NBN expression was demonstrated in one carrier. However, in one family it failed to co-segregate with BC, while the other carrier was found to harbor also a probably pathogenic TP53 variant that may explain her phenotype. Therefore, the c.156_157delTT, although functionally deleterious, was not supported as a cancer-predisposing defect. Pathogenic/likely pathogenic NBN variants were detected by multigene panels in 31/12314 (0.25%) patients included in 15 studies. The risk of misinterpretation of such findings is substantial and supports the exclusion of NBN from multigene panels.

Immune cytopenias as a continuum in inborn errors of immunity: An in-depth clinical and immunological exploration.

BACKGROUND: Immune thrombocytopenia (ITP), autoimmune hemolytic anemia (AIHA), and autoimmune neutropenia (AIN) are disorders characterized by immune-mediated destruction of hematopoietic cell lineages. A link between pediatric immune cytopenias and inborn errors of immunity (IEI) was established in particular in the combined and chronic forms. OBJECTIVE: Aim of this study is to provide clinical-immunological parameters to hematologists useful for a prompt identification of children with immune cytopenias deserving a deeper immunological and genetic evaluation. METHODS: We retrospectively collected 47 pediatric patients with at least one hematological disorder among which persistent/chronic ITP, AIHA, and AIN, aged 0-18 years at onset of immune cytopenias and/or immune-dysregulation. The cohort was divided into two groups (IEI+ and IEI-), based on the presence/absence of underlying IEI diagnosis. IEI+ group, formed by 19/47 individuals, included: common variable immune deficiency (CVID; 9/19), autoimmune lymphoproliferative syndrome (ALPS; 4/19), DiGeorge syndrome (1/19), and unclassified IEI (5/19). RESULTS: IEI prevalence among patients with ITP, AIHA, AIN, and Evans Syndrome was respectively of 42%, 64%, 36%, and 62%. In IEI+ group the extended immunophenotyping identified the presence of statistically significant (p < .05) specific characteristics, namely T/B lymphopenia, decrease in naїve T-cells%, switched memory B-cells%, plasmablasts%, and/or immunoglobulins, increase in effector/central memory T-cells% and CD21low B-cells%. Except for DiGeorge and three ALPS patients, only 2/9 CVID patients had a molecular diagnosis for IEI: one carrying the pathogenic variant CR2:c.826delT, the likely pathogenic variant PRF1:c.272C> and the compound heterozygous TNFRSF13B variants p.Ser144Ter (pathogenic) and p.Cys193Arg (variant of uncertain significance), the other one carrying the likely pathogenic monoallelic variant TNFRSF13B:p.Ile87Asn. CONCLUSION: The synergy between hematologists and immunologists can improve and fasten diagnosis and management of patients with immune cytopenias through a wide focused clinical/immunophenotypical characterization, which identifies children worthy of IEI-related molecular analysis, favouring a genetic IEI diagnosis and potentially unveiling new targeted-gene variants responsible for IEI phenotype.

An Analysis of Clinical, Surgical, Pathological and Molecular Characteristics of Endometrial Cancer According to Mismatch Repair Status. A Multidisciplinary Approach.

Since 2016, our hospital has applied tumor testing with immunohistochemistry (IHC) in endometrial cancer in order to detect mutations of mismatch repair genes (MMR). All cases with MMR deficiency proteins expression are sent for genetic testing, except those with MLH1 protein deficiency, in which case genetic testing is performed if negative for promoter hypermethylation. The primary aim of this study was to investigate the ability of our algorithm to identify Lynch syndrome (LS). The Secondary aims were to investigate the relationship between MMR status and clinicopathological features and prognosis of primary endometrial cancer (EC). From January 2016 to December 2018, 239 patients with EC were retrospectively analyzed and subdivided according to MMR status. Patients were divided in three groups: MMR proficient, LS and Lynch-like cancer (LLC). LS was characterized by a lower age and BMI, more use of contraceptive and less use of hormonal replacement therapy, nulliparity and a trend versus a better prognosis. LLC appeared more related to MMR proficient than LS and exhibited a more aggressive behavior. Our multidisciplinary approach permitted a correct diagnosis of germline mutation in patients with newly diagnosis EC and it confirmed clinicopathologic and prognostic characteristics of LS.

RASAL1 and ROS1 Gene Variants in Hereditary Breast Cancer.

Breast cancer (BC) is the second leading cause of death in women. BC patients with family history or clinical features suggestive of inherited predisposition are candidate to genetic testing to determine whether a hereditary cancer syndrome is present. We aimed to identify new predisposing variants in familial BC patients using next-generation sequencing approaches. We performed whole exome sequencing (WES) in first-degree cousin pairs affected by hereditary BC negative at the BRCA1/2 (BReast CAncer gene 1/2) testing. Targeted analysis, for the genes resulting mutated via WES, was performed in additional 131 independent patients with a suspected hereditary predisposition (negative at the BRCA1/2 testing). We retrieved sequencing data for the mutated genes from WES of 197 Italian unrelated controls to perform a case-controls collapsing analysis. We found damaging variants in NPL (N-Acetylneuraminate Pyruvate Lyase), POLN (DNA Polymerase Nu), RASAL1 (RAS Protein Activator Like 1) and ROS1 (ROS Proto-Oncogene 1, Receptor Tyrosine Kinase), shared by the corresponding cousin pairs. We demonstrated that the splice site alterations identified in NPL and ROS1 (in two different pairs, respectively) impaired the formation of the correct transcripts. Target analysis in additional patients identified novel and rare damaging variants in RASAL1 and ROS1, with a significant allele frequency increase in cases. Moreover, ROS1 achieved a significantly higher proportion of variants among cases in comparison to our internal control database of Italian subjects (p = 0.0401). Our findings indicate that germline variants in ROS1 and RASAL1 might confer susceptibility to BC.

Long-term follow-up of 168 patients with X-linked agammaglobulinemia reveals increased morbidity and mortality.

BACKGROUND: X-linked agammaglobulinemia (XLA) is the prototype of primary humoral immunodeficiencies. Long-term follow-up studies regarding disease-related complications and outcome are scarce. OBJECTIVE: Our aim was to describe the natural history of XLA. METHODS: A nationwide multicenter study based on the Italian Primary Immunodeficiency Network registry was established in 2000 in Italy. Affected patients were enrolled by documenting centers, and the patients' laboratory, clinical, and imaging data were recorded on an annual base. RESULTS: Data on the patients (N = 168) were derived from a cumulative follow-up of 1370 patient-years, with a mean follow-up of 8.35 years per patient. The mean age at diagnosis decreased after establishment of the Italian Primary Immunodeficiency Network registry (84 months before vs 23 months after). Respiratory, skin, and gastrointestinal manifestations were the most frequent clinical symptoms at diagnosis and during long-term follow-up. Regular immunoglobulin replacement treatment reduced the incidence of invasive infections. Affected patients developed chronic lung disease over time (47% after 40 years of follow-up) in the presence of chronic sinusitis (84%). Malignancies were documented in a minority of cases (3.7%). Overall survival for affected patients was significantly reduced when compared with that for the healthy male Italian population, and it further deteriorated in the presence of chronic lung disease. CONCLUSIONS: This is the first detailed long-term follow-up study for patients with XLA, revealing that although immunoglobulin replacement treatment reduces the incidence of invasive infections, it does not appear to influence the development of chronic lung disease. The overall survival of affected patients is reduced. Further studies are warranted to improve patients' clinical management and increase awareness among physicians.

Morphometric analysis of atypical glandular cells correctly classifies normal, reactive, and atypical cells in cervical smears.

The 2014 Bethesda System diagnostic criteria for atypical glandular cells (AGC) aid in the classification of atypical cells in cervical cytology. Anyway, AGC diagnosis remains challenging, due to low frequencies of this finding (approximately 0.5%-1% of Pap test results), abundance of AGC mimics, and significant interobserver variability. We developed an algorithm based on nuclear areas parameter that can help to differentiate AGC from Normal and Reactive glandular cells. Nuclear areas and perimeters were measured on 16 Pap smears with AGC and 18 with Reactive glandular cells of women aged between 30 and 77. Glandular cells from nonpathological Pap smears were used as controls. For each case, the means, medians, standard deviations, and the minimum and maximum values of both nuclear areas and perimeters of the cells of interest were calculated. The nuclear area analysis showed a 100% specificity in discriminating Normal from Altered cells (either Reactive or AGC), whereas the nuclear perimeter analysis showed a lower specificity (87.5%). Both nuclear area and perimeter variability analysis resulted in high specificity values in distinguishing Reactive cells from AGC. Therefore, a stepwise two-step algorithm using nuclear areas to discriminate Normal from Altered cells, and nuclear area variability to distinguish Reactive from AGC, allowed us to reliably classify the cells into these three categories. The morphometric analysis of nuclear area is a valuable and reliable aid in AGC diagnosis and standardization, easily integrable into common automatic algorithms.

Rare TACI Mutation in a 3-Year-Old Boy With CVID Phenotype.

Common variable immunodeficiency (CVID) is the most common and clinically relevant primary immunodeficiency (PID). Genetic basis of CVID remains largely unknown. However, in a minority of CVID patients, a number of distinct genetic defects affecting the normal processes of B cell maturation and differentiation into memory B cells have now been identified, resulting in markedly reduced serum levels of immunoglobulin G (IgG) and low immunoglobulin A (IgA) or immunoglobulin M (IgM), with impaired antibody responses, despite the presence of normal levels of B cells. Patients with CVID develop recurrent and chronic infections of respiratory and gastrointestinal tracts, autoimmune diseases, lymphoproliferative complications, malignancies, and granulomatous disease. We report the case of a boy admitted to our unit for the first time at the age of three for reduced gamma globulin levels and a clinical history positive for two episodes of pneumonia. Our patient incompletely met ESID diagnostic criteria for CVID, but molecular genetic analysis, a NGS panel including 47 PID-associated genes was performed in the proband and in his parents, revealing the presence of a heterozygous nucleotide substitution in exon 4 (c.579C>A) of TNFRSF13B encoding TACI. This mutation has been described only in two CVID adult patients and in a child with selective IgA deficiency (sIgAD). We highlighted the same mutation in the asymptomatic mother and detected two extra heterozygous mutations of RIG1 and LIG1. We promptly started intravenous immunoglobulin (IVIG) therapy with good tolerance. Despite the diagnosis of CVID remains clinical, in this case report we underline the importance of considering and planning genetic workup in all subjects with unclear diagnosis and of reporting new molecular diagnosis especially in case of rare mutations.

Follow-up and outcome of symptomatic partial or absolute IgA deficiency in children.

Selective IgA deficiency is defined as absolute or partial when serum IgA level is < 7 mg/dl or 2 SD below normal for age, respectively. Few data are available on partial selective IgA deficiency, as probably most children with low serum IgA are seldom referred to a specialist clinic in common pediatric practice. The aim of our study was to better define the profile of both symptomatic forms and their clinical outcome in a pediatric immunology setting. Thus, clinical and immunological data from 103 symptomatic patients with selective IgA deficiency (53 absolute and 50 partial), 4-18 years of age, were collected at diagnosis and 80 patients (44 absolute and 36 partial) were monitored for a mean period of 5 years. Also, the prevalence of TNFRSF13B mutations has been assessed in 56 patients. The most common clinical features were infections (86/103; 83%), allergy (39/103; 38%), and autoimmunity (13/103; 13%). No significative differences were observed between absolute and partial selective IgA deficiency patients. However, a significative difference in the rate of IgA normalization between partial and absolute selective IgA deficiency patients (33 vs 9%, p = 0.01) was detected. Furthermore, a lower incidence of infections was associated to a normalization reversal compared to a final absolute or partial defect status (12 vs 53 and 64% respectively, p < 0.01).Conclusions: Regardless of a diagnosis of absolute or partial defect, monitoring of symptomatic patients with selective IgA deficiency is recommended overtime for prompt identification and treatment of associated diseases. Further, diagnostic workup protocols should be revisited in children with IgA deficiency. What is Known: ● Selective IgA Deficiency is the most common primary immunodeficiency and is usually asymptomatic. ● Symptomatic pediatric patients with selective IgA deficiency mostly suffer with respiratory and gastrointestinal infections. What is New: ● Symptomatic children with partial IgA defect may have similar clinical, immunological, and genetic features than symptomatic children with absolute IgA deficiency. ● Symptomatic children with partial IgA deficiency deserve accurate monitoring for associated diseases as per children with absolute IgA deficiency.

Dealing With BRCA1/2 Unclassified Variants in a Cancer Genetics Clinic: Does Cosegregation Analysis Help?

Background: Detection of variants of uncertain significance (VUSs) in BRCA1 and BRCA2 genes poses relevant challenges for counseling and managing patients. VUS carriers should be managed similarly to probands with no BRCA1/2 variants detected, and predictive genetic testing in relatives is discouraged. However, miscomprehension of VUSs is common and can lead to inaccurate risk perception and biased decisions about prophylactic surgery. Therefore, efforts are needed to improve VUS evaluation and communication at an individual level. Aims: We aimed at investigating whether cosegregation analysis, integrated with a careful review of available functional data and in silico predictions, may improve VUSs interpretation and counseling in individual families. Methods: Patients with Breast Cancer (BC) and/or Ovarian Cancer (OC) fulfilling established criteria were offered genetic counseling and BRCA1/2 testing; VUSs identified in index cases were checked in other relatives affected by BC/OC whenever possible. As an alternative, if BC/OC clustered only in one branch of the family, the parental origin of the VUS was investigated. Public prediction tools and databases were used to collect additional information on the variants analyzed. Results: Out of 1045 patients undergoing BRCA1/2 testing in the period October 2011-April 2018, 66 (6.3%) carried class 3 VUSs. Cosegregation analysis was performed for 13 VUSs in 11 kindreds. Seven VUSs (53.8%) did not cosegregate with breast/ovarian cancer in the family, which provided evidence against their role in cancer clustering in those families. Among the 6 cosegregating VUSs, for two (BRCA1 c.5152+2T>G and BRCA2 c.7975A>G) additional evidence exists from databases and in silico tools supporting their pathogenicity, which reinforces the hypothesis they may have had a predisposing effect in respective families. For the remaining four VUSs (31%), cosegregation analysis failed to provide relevant information. Conclusion: Our findings suggest that cosegregation analysis in a clinical context may be helpful to improve test result interpretation in the specific family and, therefore, should be offered whenever possible. Besides, obtaining and sharing cosegregation data helps gathering evidence that may eventually contribute to VUS classification.

BRCA1 p.His1673del is a pathogenic mutation associated with a predominant ovarian cancer phenotype.

We have investigated the clinical significance of the BRCA1 variant p.His1673del in 14 families from the Emilia-Romagna region of Italy, including 20 breast and 23 ovarian cancer cases; four families displayed site-specific ovarian cancer.The variant, absent in human variation databases, has been reported three times in BRCA1 specific databases; all probands shared the same rare haplotype at the BRCA1 locus, consistent with a common ancestor.The multifactorial likelihood method by Goldgar, used to estimate the probability of the variant being causative, gave a ratio of 2,263,474:1 in favor of causality. Moreover, in silico modeling suggested that His1673-lacking BRCA1 protein may have a decreased ability to bind BARD1 and other related proteins. All six ovarian carcinomas and two out of four breast carcinomas available showed a loss of the BRCA1 wild-type allele, which in three out of four ovarian carcinomas analyzed by FISH was associated with duplication of the chromosome 17 containing the variant. Although the pathogenicity of the allele is strongly supported by the multifactorial ratio,we cannot exclude that p.His1673del is not itself deleterious, but is linked to another undetected mutation on the same ancestral allele.

Clinical Associations of Biallelic and Monoallelic TNFRSF13B Variants in Italian Primary Antibody Deficiency Syndromes.

We assessed the prevalence of TNFRSF13B mutations and the clinical correlates in an Italian cohort of 189 CVID, 67 IgAD patients, and 330 healthy controls to substantiate the role of TACI genetic testing in diagnostic workup. We found that 11% of CVID and 13% of IgAD carried at least one mutated TNFRSF13B allele. Seven per cent of CVID had monoallelic-mutations and 4% had biallelic-mutations. The frequency of C104R monoallelic-mutations was not higher than that found in healthy controls. Biallelic-mutations were exclusively found in CVID. CVID patients carrying monoallelic-mutations had an increased prevalence of lymphadenopathy, granulomata, and autoimmune cytopenias. CVID carrying biallelic-mutations had a low prevalence of autoimmunity in comparison with TACI wild-type CVID. Moreover, biallelic-mutated CVID had higher frequency of switched memory B-cells and higher IgM and IgA antibodies to polysaccharide antigens than TACI wild-type and monoallelic-mutated CVID. TACI-mutated IgAD patients had only monoallelic-mutations and did not display clinical difference from IgAD wild-type patients. In conclusion, TNFRSF13B genetic screening of antibody deficiencies may allow the identification of mutational patterns. However, as with counseling for risk assessment, geneticists should be aware that the interpretation of genetic testing for TACI mutations is difficult and the potential impact on clinical management is still limited.