Case Report: Characterization of known (c.607G>C) and novel (c.416C>G) ELANE mutations in two Mexican families with congenital neutropenia.

The most common causes of congenital neutropenia are mutations in the ELANE (Elastase, Neutrophil Expressed) gene (19p13.3), mostly in exon 5 and the distal portion of exon 4, which result in different clinical phenotypes of neutropenia. Here, we report two pathogenic mutations in ELANE, namely, c.607G>C (p.Gly203Arg) and a novel variant c.416C>G (p.Pro139Arg), found in two Mexican families ascertained via patients with congenital neutropenia who responded positively to the granulocyte colony-stimulating factor (G-CSF) treatment. These findings highlight the usefulness of identifying variants in patients with inborn errors of immunity for early clinical management and the need to rule out mosaicism in noncarrier parents with more than one case in the family.

Mendelian Susceptibility to Mycobacterial Disease: Retrospective Clinical and Genetic Study in Mexico.

Mendelian susceptibility to mycobacterial disease (MSMD) is a rare genetic disorder characterized by impaired immunity against intracellular pathogens, such as mycobacteria, attenuated Mycobacterium bovis-Bacillus Calmette-Guérin (BCG) vaccine strains, and environmental mycobacteria in otherwise healthy individuals. Retrospective study reviewed the clinical, immunological, and genetic characteristics of patients with MSMD in Mexico. Overall, 22 patients diagnosed with MSMD from 2006 to 2021 were enrolled: 14 males (64%) and eight females. After BCG vaccination, 12 patients (70%) developed BCG infection. Furthermore, 6 (22%) patients developed bacterial infections mainly caused by Salmonella, as what is described next in the text is fungal infections, particularly Histoplasma. Seven patients died of disseminated BCG disease. Thirteen different pathogenic variants were identified in IL12RB1 (n = 13), IFNGR1 (n = 3), and IFNGR2 (n = 1) genes. Interleukin-12Rß1 deficiency is the leading cause of MSMD in our cohort. Morbidity and mortality were primarily due to BCG infection.

Supervivenciade pacientes pediátricos con inmunodeficiencias primarias en un hospital público del occidente de México / Survival of pediatric patients with primary immunodeficiencies in a public hospital in western Mexico

Se presenta una serie de casos de inmunodeficiencias primarias y se describen las variables asociadas a supervivencia en pacientes ≤ 16 años. Los diagnósticos fueron acordes a los criterios de la Unión Internacional de las Sociedades de Inmunología. Se realizó un análisis de supervivencia mediante curvas de Kaplan-Meier.Entre los años 2004 y 2019, se diagnosticaron 40 pacientes con inmunodeficiencias primarias. Las más frecuentes fueron inmunodeficiencias que afectaban la inmunidad celular y humoral, el 32,5 %, y deficiencias predominantemente de anticuerpos, el 32,5 %. La mediana de edad al inicio de los síntomas y al momento del diagnóstico fue de 3,01 y 10,4 meses, respectivamente. Fallecieron el 35 % y el riesgo fue mayor en pacientes con inmunodeficiencias que afectaban la inmunidad celular y humoral y en quienes presentaron manifestaciones clínicas y tuvieron el diagnóstico en los primeros seis meses de vida.

A case series of primary immunodeficiencies is presented and outcome measures associated with survival among patients ≤ 16 years old are described. Diagnoses were made based on the criteria by the International Union of Immunological Societies. Survival was analyzed using Kaplan-Meier curves.Between 2004 and 2019, 40 patients were diagnosed with primary immunodeficiencies. The most common were immunodeficiencies affecting humoral and cell-mediated immunity (32.5 %) and predominantly antibody deficiencies (32.5 %). The median age at the onset of symptoms and at the time of diagnosis was 3.01 and 10.4 months, respectively. Thirty-five percent of patients died, and the risk was higher among those with immunodeficiencies affecting humoral and cell-mediated immunity and those who developed clinical manifestations and were diagnosed in the first 6 months of life

Clinical Manifestations, Mutational Analysis, and Immunological Phenotype in Patients with RAG1/2 Mutations: First Cases Series from Mexico and Description of Two Novel Mutations.

Mutations in recombinase activating genes 1 and 2 (RAG1/2) result in human severe combined immunodeficiency (SCID). The products of these genes are essential for V(D)J rearrangement of the antigen receptors during lymphocyte development. Mutations resulting in null-recombination activity in RAG1 or RAG2 are associated with the most severe clinical and immunological phenotypes, whereas patients with hypomorphic mutations may develop leaky SCID, including Omenn syndrome (OS). A group of previously unrecognized clinical phenotypes associated with granulomata and/or autoimmunity have been described as a consequence of hypomorphic mutations. Here, we present six patients from unrelated families with missense variants in RAG1 or RAG2. Phenotypes observed in these patients ranged from OS to severe mycobacterial infections and granulomatous disease. Moreover, we report the first evidence of two variants that had not been associated with immunodeficiency. This study represents the first case series of RAG1- or RAG2-deficient patients from Mexico and Latin America.

Survival of pediatric patients with primary immunodeficiencies in a public hospital in western Mexico. / Supervivencia de pacientes pediátricos con inmunodeficiencias primarias en un hospital público del occidente de México.

A case series of primary immunodeficiencies is presented and outcome measures associated with survival among patients ≤ 16 years old are described. Diagnoses were made based on the criteria by the International Union of Immunological Societies. Survival was analyzed using Kaplan-Meier curves. Between 2004 and 2019, 40 patients were diagnosed with primary immunodeficiencies. The most common were immunodeficiencies affecting humoral and cell-mediated immunity (32.5 %) and predominantly antibody deficiencies (32.5 %). The median age at the onset of symptoms and at the time of diagnosis was 3.01 and 10.4 months, respectively. Thirty-five percent of patients died, and the risk was higher among those with immunodeficiencies affecting humoral and cell-mediated immunity and those who developed clinical manifestations and were diagnosed in the first 6 months of life.

Se presenta una serie de casos de inmunodeficiencias primarias y se describen las variables asociadas a supervivencia en pacientes ≤ 16 años. Los diagnósticos fueron acordes a los criterios de la Unión Internacional de las Sociedades de Inmunología. Se realizó un análisis de supervivencia mediante curvas de Kaplan-Meier. Entre los años 2004 y 2019, se diagnosticaron 40 pacientes con inmunodeficiencias primarias. Las más frecuentes fueron inmunodeficiencias que afectaban la inmunidad celular y humoral, el 32,5 %, y deficiencias predominantemente de anticuerpos, el 32,5 %. La mediana de edad al inicio de los síntomas y al momento del diagnóstico fue de 3,01 y 10,4 meses, respectivamente. Fallecieron el 35 % y el riesgo fue mayor en pacientes con inmunodeficiencias que afectaban la inmunidad celular y humoral y en quienes presentaron manifestaciones clínicas y tuvieron el diagnóstico en los primeros seis meses de vida.