Maria Pina Barca

Mutation of the angiopoietin-1 gene (ANGPT1) associates with a new type of hereditary angioedema

Background: Hereditary angioedema (HAE) is a rare genetic disease usually caused by mutation in the C1 inhibitor or the coagulation Factor XII gene. However, in a series of patients with HAE, no causative variants have been described, and the pathophysiology of the disease remains unknown (hereditary angioedema with yet unknown genetic defect [U‐HAE]). Identification of causative genes in patients with U‐HAE is valuable for understanding the cause of the disease. Objective: We conducted genetic studies in Italian patients with U‐HAE to identify novel causative genes. Methods: Among patients belonging to 10 independent families and unrelated index patients with U‐HAE recruited from the Italian Network for C1‐INH‐HAE (ITACA), we selected a large multiplex family with U‐HAE and performed whole‐exome sequencing. The angiopoietin‐1 gene (ANGPT1) was investigated in all patients with familial or sporadic U‐HAE. The effect of ANGPT1 variants was investigated by using in silico prediction and plasma and transfected cells from both patients and control subjects. Results: We identified a missense mutation (ANGPT1, c.807G>T, p.A119S) in a family with U‐HAE. The ANGPT1 p.A119S variant was detected in all members of the index family with U‐HAE but not in asymptomatic family members or an additional 20 patients with familial U‐HAE, 22 patients with sporadic U‐HAE, and 200 control subjects. Protein analysis of the plasma of patients revealed a reduction of multimeric forms and a reduced ability to bind the natural receptor tunica interna endothelial cell kinase 2 of the ANGPT1 p.A119S variant. The recombinant mutated ANGPT1 p.A119S formed a reduced amount of multimers and showed reduced binding capability to its receptor. Conclusion: ANGPT1 impairment is associated with angioedema, and ANGPT1 variants can be the basis of HAE.

TH17 cells are increased in the peripheral blood of patients with SAPHO syndrome

Abstract To assess whether the immune derangement previously observed in SAPHO syndrome could be linked to variations in blood TH1, TH2 or TH17 lymphocytes frequency. Seven SAPHO patients with a protracted course of the disease were studied ex-vivo for intracellular cytokines production by means of flow-cytometry and compared with matched groups of Psoriatic Arthritis patients and healthy controls. The Kruskal–Wallis test on the median of the three categories showed that there is a significant association between the TH17 levels and the category (p value = 0.02474). The mean and variance for the proportion of IL-17 producing CD4+ cells were compared between groups showing significant differences between SAPHO versus PsA subgroup (p = 0.05) and SAPHO versus healthy controls (p = 0.008). Interestingly, activation of TH17 axis, but not of TH1 and TH2, has been found, and can be observed both in patients with different activity of the disease or treated with different drugs. The TH17 increase in peripheral blood of our SAPHO subjects resembles the one recently found in patients with different AIDs. Novel therapeutic options in these patients may therefore include IL-17 blockade.

Biological Treatments for SAPHO Syndrome: An Update

Synovitis, Acne, Pustulosis, Hyperostosis and Osteitis (SAPHO) syndrome is a rare and often unrecognized disease with prominent inflammatory cutaneous and articular manifestations. Since the identification of the syndrome many immunosuppressive drugs have been used for the management of SAPHO, with variable results. The use of anti- TNF-α agents as a therapeutic option for SAPHO cases unresponsive or refractory to conventional drugs, demonstrated their efficacy for bone, skin and joints manifestations. TNF-α is a pro-inflammatory cytokine and pivotal regulator of other cytokines, including IL-1 β , IL-6 and IL-8, involved in inflammation, acute-phase response induction and chemotaxis. IL-1 inhibition strategies with Anakinra have proven their efficacy as first and second line treatment. We herein review the literature concerning the use of biological drugs in patients with SAPHO syndrome. In addition, we describe for the first time the use of Ustekinumab, an antibody against the p40 subunit of IL-12 and IL-23, after failure of multiple drugs including anti-TNF-α and Anakinra. This anti-IL12/IL23 agent could be a promising therapeutic option, also considering the opportunity to interfere with the IL23/TH17 pathway, which we recently found disturbed. Furthermore, a rationale emerges for the use of the new anti-IL-1 antagonists or the IL-17 blockade, in particular for the most difficult-to-treat SAPHO cases.

Characterization of patients with angioedema without wheals: The importance of F12 gene screening

Sporadic and familiar forms of non-histaminergic angioedema and normal C1 inhibitor encompass a group of disorders possibly caused by bradikinin. We aimed to study the subgroups of hereditary angioedema with FXII mutation (FXII-HAE), unknown genetic defect (U-HAE) and idiopathic non-histaminergic acquired angioedema (InH-AAE). We screened the F12 locus in our cohort and delineated the clinical, laboratory and genetic features. Four families carried the p.Thr309Lys mutation in F12 gene. Haplotyping confirmed the hypothesis of a common founder. Six families were affected by U-HAE and 13 patients by sporadic InH-AAE. C4 levels were significantly lower in FXII-HAE than in InH-AAE. In the FXII-HAE group, none had attacks exclusively in high estrogenic states; acute attacks were treated with icatibant. Prophylaxis with tranexamic acid reduced the attack frequency in most patients. Our study provides new data on the diagnosis, clinical features and treatment of non-histaminergic angioedema, underlying the role of the screening for F12 mutations.

Successful Treatment of Chronic Mucocutaneous Candidiasis Caused by Azole-Resistant Candida albicans with Posaconazole

Refractory or recurrent infections of skin, nails, and the mucous membranes are clinical signs of chronic mucocutaneous candidiasis, frequently associated with immunological defects. Here we describe a 39-years-old female patient, with familial CMC, that presented with an extensive infection caused by an azole-resistant Candida albicans isolate, successfully treated with posaconazole.

Identification of a novel and recurrent mutation in the SERPING1 gene in patients with hereditary angioedema

Hereditary angioedema (HAE) due to C1 inhibitor (C1-INH) deficiency is an autosomal dominant disorder caused by mutations in SERPING1 gene. More than 200 different mutations are known, with high genetic heterogeneity and high frequency of private familial mutations. We analyzed for genetic mutations the C1-INH locus in 11 Sardinian families, revealing in seven subjects from four unrelated families the novel nonsense mutation S318X. This mutation, detected with unexpected high frequency, accounts for over a third of the here reported Sardinian families affected by HAE. The recurrence of a pathogenic mutation within the same geographical area is a unique finding, previously unreported in HAE due to C1-INH deficiency.

Systemic reactive (AA) amyloidosis in the course of common variable immunodeficiency.

Patients with primary immunodeficiencies (PID) are currently at low risk for the development of systemic reactive AA amyloidosis. A patient with common variable immunodeficiency and nephrotic syndrome was referred to our Clinic from a Nephrology unit. She had a history of recurrent infections. Monthly intramuscular immunoglobulin substitution treatment was started in 1979, subsequently switched to intravenous route. Between 1984 and 2007, she continued to experience infections and did not have follow-up visits in an Immunology Centre. Replacement therapy was discontinued in 2008 for adverse events related to IVIG infusion; since then she was admitted for recurrent cellulitis, sepsis, and pneumonia. In 2009, the patient developed massive proteinuria and renal failure due to clinically overt reactive systemic AA amyloidosis. Despite the prompt resumption of antibody replacement, adequate IgG levels were not achieved and SAA concentration remained elevated. Delay in diagnosis and inadequate treatment of PIDs results in increased irreversible complications, including AA amyloidosis. Introduction: The primary immunodeficiencies (PIDs) are a heterogeneous group of inherited disorders that affect the cells and proteins of the immune system. Defects in antibody production are the most common type, comprising about 60% of the primary immunodeficiencies encountered in practice. Patients with predominantly antibody deficiencies, such as common variable immunodeficiency (CVID), are recognized to have immunodeficiency in the second, third, or fourth decade of life, after they have had several bouts of pneumonia; however, children and older adults may be affected. The diagnosis is defined by the severe reduction of at least two immunoglobulin isotypes, a poor response to vaccination, the onset after the second year of life, and the exclusion of defined differential diagnosis [1]. Approximately, 50% of patients have autoimmune manifestations and there is an increased risk of malignancy. In recent years, the first monogenic defects have been identified in ICOS, TACI, CD19, BAFF-R [2]. The mainstay of treatment in CVID is lifelong replacement of antibody, today achieved by either intravenous (IVIG) or subcutaneous (s.c.) route of immunoglobulin (Ig), usually in doses of 0.4–0.6 g/ kg body weight a month. When treated with replacement therapy in appropriate doses there is a significant reduction in incidence of infections. Patients with PIDs are currently at low risk for the development of systemic reactive AA amyloidosis. Methods: A 66-year-old patient with CVID and nephrotic syndrome was referred to our Clinic from a Nephrology unit. She had been diagnosed at the age of 31 years as having severe hypogammaglobulinemia, presenting with a history of recurrent sinupulmonary infections, otitis, and diarrhea due to gastrointestinal infections and giardiasis. At that time, she had no evidence of proteinuria or renal impairment and secondary causes of hypogammaglobulinemia were excluded as well. Monthly intramuscular immunoglobulin substitution treatment was started in 1979. Dose had been increased over the 3 years following and subsequently she was switched from this route of administration to intravenous infusion. Between 1984 and 2007, the patient experienced relapsing infections (mainly of sinuses, lung and bladder) and did not have followup visits in an Immunology Centre. Replacement therapy without accomplishing adequate IgG trough levels was discontinued in 2008 for moderate adverse events (malaise, fever, flushing, and anaphylactoid symptoms) related to IVIG infusion. Since then, she required hospitalization for recurrent cellulitis of lower extremities, sepsis and multiple episodes of pneumonia. In early 2009, patient developed massive proteinuria (exceeding 20 g/24 h) and renal failure due to clinically overt reactive systemic AA amyloidosis. A kidney biopsy was performed on 25 March 2009, and histological examination of specimen revealed eosinophilic material infiltrating the mesangium and vessel walls. This material stained positively with Congo red, and the deposits showed intense apple-green birefringence under polarized light, consistent with the presence of amyloid. On immunohistochemistry, the amyloid deposits were intensively and specifically stained with anti-amyloid A antibody and were negative for other amyloidogenic proteins which are known to target the kidney. On admission to our hospital in July 2009, laboratory data included IgG 0 mg/dl (694–1618), and IgA 1 mg/dl (48–271,) but normal IgM. Total protein was 3.9 g/dl, albumin was 1.68 g/dl (normal 3.2–5.35), and proteinuria 4.3 g/24 h with significant loss of polyclonal IgG on urine immunofixation electrophoresis (Figure 1). Serum amyloid A (SAA) concentration was 45.1 mg/l (normal 56.8). We confirmed diagnosis of CVID complicated by AA amyloidosis and promptly started high-dose IVIG (using premedication with acetaminophen, steroids, and antihistamines) and intravenous antibiotics to treat urinary tract infection and recurrence of 214

Oxidative stress markers in patients with hereditary angioedema

Introduction Hereditary angioedema due to C1-INH deficiency (C1-INH-HAE) or with normal C1-INH is characterized by recurrent swellings due to uncontrolled production of vasoactive mediators, among which bradykinin (BK) is crucial. Through the binding and activation of the two human BK-receptors, kinins may have dual beneficial and deleterious effects in vascular and inflammation physiopathology by inducing oxidative stress. We aimed to assess the serum concentrations of advanced glycation end products (AGEs) and advanced oxidation protein products (AOPPs) in patients affected by HAE. Material and methods Blood samples were collected to measure the serum concentrations of AGEs and AOPPs by spectrofluorimetric and spectrophotometric methods in patients affected by C1-INH-HAE and FXII-HAE during the remission state. Results We showed that the circulating levels of AOPPs observed on control group (0.94 (0.36) nmol/mg) were significantly lower than those observed on the C1-INH-HAE group (1.68 (0.47) nmol/mg; p = 0.002) and FXII-HAE (1.50 (0.27) nmol/mg; p = 0.001). Moreover, the circulating levels of AGEs were significantly higher in C1-INH-HAE group (211.58 (151.05) AU/g; p = 0.02) than the FXII group (141.48 (89.59) AU/g), thus demonstrating a state of heightened oxidative stress. Conclusions Our observations show additional underlying events involved in HAE and are of central importance for further investigations of differences in bradykinin receptors signaling among the two disease subgroups.

A nationwide survey of hereditary angioedema due to C1 inhibitor deficiency in Italy.

Introduction: Hereditary angioedema due to C1-inhibitor deficiency (C1-INH-HAE type I) or dysfunction (C1-INH-HAE type II) is a rare disease characterized by recurrent episodes of edema with an estimated frequency of 1:50,000 in the global population without racial or gender differences. In this study we present the results of a nationwide survey of C1-INH-HAE patients referring to 17 Italian centers, the Italian network for C1-INH-HAE, ITACA.