Clinical, Immunological, and Genetic Findings in Iranian Patients with MHC-II Deficiency: Confirmation of c.162delG RFXANK Founder Mutation in the Iranian Population.

PURPOSE: Major histocompatibility complex class II (MHC-II) deficiency is a rare inborn error of immunity (IEI). Impaired antigen presentation to CD4 + T cells results in combined immunodeficiency (CID). Patients typically present with severe respiratory and gastrointestinal tract infections at early ages. Hematopoietic stem cell transplantation (HSCT) is the only curative therapy. METHODS: We describe the clinical, immunologic, and genetic features of eighteen unrelated Iranian patients with MHC-II deficiency. RESULTS: Consanguinity was present in all affected families. The median age at the initial presentation was 5.5 months (range 7 days to 18 years). The main symptoms included failure to thrive, persistent diarrhea, and pneumonia. Autoimmune and neurologic features were also documented in about one-third of the patients, respectively. Thirteen patients carried RFXANK gene mutations, two carried RFX5 gene mutations, and three carried a RFXAP gene mutation. Six patients shared the same RFXANK founder mutation (c.162delG); limited to the Iranian population and dated to approximately 1296 years ago. Four of the patients underwent HSCT; three of them are alive. On the other hand, nine of the fourteen patients who did not undergo HSCT had a poor prognosis and died. CONCLUSION: MHC-II deficiency is not rare in Iran, with a high rate of consanguinity. It should be considered in the differential diagnosis of CID at any age. With the limited access to HSCT and its variable results in MHC-II deficiency, implementing genetic counseling and family planning for the affected families are mandatory. We are better determined to study the c.162delG RFXANK heterozygous mutation frequency in the Iranian population.

Pulmonary manifestations in a cohort of patients with inborn errors of immunity: an 8-year follow-up study.

BACKGROUND: Inborn errors of immunity (IEIs) are a group of congenital diseases caused by genetic defects in the development and function of the immune system. The involvement of the respiratory tract is one of the most common presentations in IEIs. METHODS: Overall, 117 patients with diagnosed IEIs were followed-up within 8 years at the National Research Institute of Tuberculosis and Lung Diseases (NRITLD). Demographic, clinical, and laboratory data were collected in a questionnaire. Pulmonary function test (PFT), chest X-ray (CXR), and high-resolution computed tomography (HRCT) scans were obtained where applicable. RESULTS: Our study population consisted of 48 (41%) patients with predominantly antibody deficiencies (PADs), 39 (32%) patients with congenital defects of phagocytes, 14 (11.9%) patients with combined immunodeficiency (CID), and 16 (14%) patients with Mendelian susceptibility to mycobacterial diseases (MSMD). . Recurrent pneumonia was the most common manifestation, while productive cough appeared to be the most common symptom in almost all diseases. PFT showed an obstructive pattern in patients with PAD, a restrictive pattern in patients with CID, and a mixed pattern in patients with CGD. HRCT findings were consistent with bronchiectasis in most PAD patients, whereas consolidation and mediastinal lesions were more common in the other groups. CONCLUSIONS: Pulmonary manifestations vary among different groups of IEIs. The screening for lung complications should be performed regularly to reveal respiratory pathologies in early stages and follow-up on already existing abnormalities.

Mendelian Susceptibility to Mycobacterial Disease (MSMD): Clinical and Genetic Features of 32 Iranian Patients.

Mendelian susceptibility to mycobacterial diseases (MSMD) is a rare congenital condition characterized by a selective predisposition to infections caused by weakly virulent mycobacteria and other types of intra-macrophagic pathogens. The 16 genes associated with MSMD display a considerable level of allelic heterogeneity, accounting for 31 distinct disorders with variable clinical presentations and prognosis. Most of MSMD deficiencies are isolated, referred to as selective susceptibility to mycobacterial diseases. However, other deficiencies are syndromic MSMD, defined by the combination of the mycobacterial infection with another, equally common, infectious, specific phenotypes. Herein, we described a series of 32 Iranian MSMD cases identified with seven distinct types of molecular defects, all of which are involved in the interferon gamma (IFNγ) immunity, including interleukin IL-12 receptor-ß1 (IL-12Rß1) deficiency (fifteen cases), IL-12p40 deficiency (ten cases), and IL-23R deficiency (three cases), as well as IFNγ receptor 1 (IFNγR1) deficiency, IFNγ receptor 2 (IFNγR2) deficiency, interferon-stimulated gene 15 (ISG15) deficiency, and tyrosine kinase 2 (TYK2) deficiency each in one case. Since the first report of two MSMD patients in our center, we identified 30 other affected patients with similar clinical manifestations. As the number of reported Iranian cases with MSMD diagnosis has increased in recent years and according to the national vaccination protocol, all Iranian newborns receive BCG vaccination at birth, early diagnosis, and therapeutic intervention which are required for a better outcome and also prevention of similar birth defects. Therefore, we investigated the clinical and molecular features of these 32 patients. The current report also defined novel classes of pathological mutations, further expanding our knowledge of the MSMD molecular basis and associated clinical manifestations.

Antibody Response Before and After the Booster Dose of Inactivated Corona Vaccine in Antibody Deficient Patients.

Patients with inborn errors of immunity (IEI) are among the high-risk groups regarding COVID-19. Receiving booster doses (third and fourth) in addition to the standard doses is recommended in these patients. This study investigated the antibody response before and after a booster dose of Sinopharm vaccine in IEI patients.  Thirty patients (>12 years) with antibody deficiencies, referred to Imam Khomeini Hospital and Children's Medical Center in Tehran, were enrolled in this prospective cross-sectional study. All patients were fully vaccinated with the BBIBP-CorV vaccine (2 doses of Sinopharm). Initial measurements of anti-receptor-binding domain (anti-RBD) and anti-nucleocapsid (anti-N) IgG antibody responses were conducted by enzyme-linked immunosorbent assay (ELISA). Subsequently, all patients received a booster dose of the vaccine. Four to six weeks after booster injection, the levels of antibodies were re-evaluated.  Twenty patients with common variable immunodeficiency (CVID), 7 cases with agammaglobulinemia and 3 patients with hyper IgM syndrome were studied. Anti-RBD IgG and anti-N IgG antibodies increased in all patients after the booster. Our results indicated the need of receiving booster doses of the COVID-19 vaccine in patients with antibody deficiencies, even for enhancing humoral immune response specially in patients with CVID.

Pulmonary complications of predominantly antibody immunodeficiencies in a tertiary lung center.

BACKGROUND AND AIMS: Respiratory infections are expressed very soon in the life in humoral immunodeficiencies and often lead to chronic irreversible complications such as bronchiectasis and chronic airflow limitation. This study was conducted to evaluate the pulmonary complications of predominantly antibody immunodeficiencies to show the benefits of timely diagnosis and appropriate therapy. PATIENTS AND METHODS: The information of 48 patients involved with a type of predominantly antibody immunodeficiencies, including sex, type of primary immunodeficiency, age at the onset of symptoms, age at diagnosis, recurrent infections, respiratory symptoms, and pulmonary radiological and functional abnormalities were recorded and analyzed. RESULTS: In 48 patients evaluated, the mean age at diagnosis was 25.63 years. The mean diagnostic delay was estimated to be 13.62 years. The most recurring clinical manifestations, sinusitis (69.6%), otitis (43.5%), and recurrent pneumonia were the cause of frequent admissions in 68.8% of these patients. Bronchiectasis was frequently found (58.3%) in these patients mostly involving the middle and lower lobes (48.8% and 41.5%, respectively). CONCLUSIONS: Respiratory complications, infectious or non-infectious, determine the prognosis of the disease in patients with predominantly antibody immunodeficiencies. Timely diagnosis and appropriate management may improve life expectancy and the quality of life in these patients.