Gesmar Rodrigues Silva Segundo

Chronic granulomatous disease (CGD) is an inborn error of immunity (IEI) caused by mutations in genes encoding components of the NADPH oxidase complex, leading to defective microbial killing and increased susceptibility to infections. This study analyzed clinical, genetic, and geospatial data from 238 CGD patients across eight Latin American countries. Genetic variants were identified in 141 patients (59%), with XL-CGD being the most common form (77%). Pneumonia (80%), lymphadenopathy (63%), and skin infections (55.5%) were frequent, with bacteria and fungi, such as Staphylococcus aureus, Aspergillus spp., and mycobacteria, as major pathogens. Antimicrobial prophylaxis was widely used, while IFN-γ was mainly prescribed in Mexico, mainly in cases of classic CGD (XL-CGD). Hematopoietic stem cell transplantation (HSCT) did not improve survival compared to prophylaxis. The leading cause of death was infection, particularly pneumonia and sepsis. XL-CGD patients had worse survival outcomes. The study highlights the need for improved genetic diagnosis, newborn screening, regional treatment guidelines, and expanded access to HSCT.

This study aimed to assess the protein expression of E-cadherin and filaggrin (FLG) in the oesophagus of paediatric and adolescent patients diagnosed with eosinophilic esophagitis (EoE). It is a cross-sectional study conducted with 24 patients with EoE and 17 control patients, from June 2015 to June 2018. The histological analyses were performed by a trained pathologist. The protein expression of E-cadherin and FLG in oesophageal biopsy fragments was determined using an immunohistochemical technique. The epidemiological data were retrieved from medical records. There were no statistical differences in age and sex between case-patients and control patients. Food allergy was significantly higher in patients with EoE, as was the number of eosinophils present in the oesophageal biopsy materials. The immunohistochemical studies did not indicate FLG expression in any patient from the two groups. E-cadherin showed significantly reduced expression in patients with EoE. We concluded that FLG did not seem to play an important role in the mucosal alteration in EoE and that E-cadherin under expression could be a promising marker of epithelial damage in these patients.

Severe combined immunodeficiency, SCID, is a pediatric emergency that represents the most critical group of inborn errors of immunity (IEI). Affected infants present with early onset life-threatening infections due to absent or non-functional T cells. Without early diagnosis and curative treatment, most die in early infancy. As most affected infants appear healthy at birth, newborn screening (NBS) is essential to identify and treat patients before the onset of symptoms. Here, we report 47 Brazilian patients investigated between 2009 and 2020 for SCID due to either a positive family history and/or clinical impression and low TRECs. Based on clinical presentation, laboratory finding, and genetic information, 24 patients were diagnosed as typical SCID, 14 as leaky SCID, and 6 as Omenn syndrome; 2 patients had non-SCID IEI, and 1 remained undefined. Disease onset median age was 2 months, but at the time of diagnosis and treatment, median ages were 6.5 and 11.5 months, respectively, revealing considerable delay which affected negatively treatment success. While overall survival was 51.1%, only 66.7% (30/45) lived long enough to undergo hematopoietic stem-cell transplantation, which was successful in 70% of cases. Forty-three of 47 (91.5%) patients underwent genetic testing, with a 65.1% success rate. Even though our patients did not come from the NBS programs, the diagnosis of SCID improved in Brazil during the pilot programs, likely due to improved medical education. However, we estimate that at least 80% of SCID cases are still missed. NBS-SCID started to be universally implemented in the city of São Paulo in May 2021, and it is our hope that other cities will follow, leading to early diagnosis and higher survival of SCID patients in Brazil.

Introduction: Cow’s milk protein allergy (CMA) is the most common type of food allergy in childhood and exclusion diet is a challenge for patients. Objective: The study aim was to investigate the frequency of tolerance to baked foods containing milk and evaluate immediate skin prick test (SPT) and specific IgEs for different cow’s milk (CM) protein types as predictors of tolerance to baked foods containing milk for CMA patients. Methods: A cross-sectional study was performed. Fifty-four CMA patients were enrolled and oral food challenge (OFC) was performed with baked product, 6 different milk SPTs and specific IgEs to CM, casein, α-lactalbumin, and β-lactoglobulin. Results: Thirty-nine (72.2%) patients tolerated OFC with baked milk cupcake. CM-specific IgE and casein SPT showed statistical difference between positive and negative OFC groups. Probability curves for baked milk tolerance were created for specific CM IgE (Z = 2.542, p < 0.0110) and casein SPT (Z = 2.290, p < 0.0220) using logistic regression. Conclusions: The high percentage of patients able to tolerate baked goods enables an improvement in intake possibilities and quality of life of CMA patients and families. Specific CM IgE and casein SPT demonstrated to be useful predictors in relation to baked milk tolerance.