Malignancies and Lymphoproliferations in Children With Primary Immune Deficiency-A Single-center Experience.

Primary immune deficiencies (PIDs) are rare genetic disorders characterized by impaired immune function, leading to frequent infections and immune dysregulation. Studies have shown that individuals with PID are at an increased risk of developing malignancies and lymphoproliferative disorders compared with the general population. In this single-center study, we aimed to analyze the occurrence of malignancies and lymphoproliferations in children diagnosed with PID. We retrospectively analyzed the medical records of 550 pediatric patients diagnosed with PIDs at our center. Among them, 17 (3,0%) patients were identified with malignancy and/or benign lymphoproliferation. Eight of the 17 patients (47.0%) had immune dysregulatory diseases, whereas ataxia-telangiectasia was the second most common PID associated with malignancy and/or benign lymphoproliferation (n = 5, 29.4%). Lymphoma was the predominant malignancy (n = 11, 64.7%), and Epstein-Barr virus was identified as the most common viral agent associated with malignancy and/or benign lymphoproliferation in patients with PID (n = 8, 47.0%). Our study highlights the association between PID and malignancies/lymphoproliferations, with immune dysregulation syndromes being the most common subclass associated with malignancies/lymphoproliferations. Early diagnosis, multidisciplinary management, and regular surveillance are crucial in improving patient outcomes and saving lives.

Risk factors predisposing children to food allergies.

BACKGROUND: Food allergies are the most common cause of anaphylaxis in children, and their incidence is increasing globally. The aim of this study was to determine the risk factors leading to food allergies in childhood. METHODS: Children with food allergies and non-atopic healthy children were compared using a questionnaire that included prenatal, neonatal, and postnatal risk factors. RESULTS: A total of 314 subjects, 155 patients and 159 healthy children for the control group, were enrolled in the study. The median age of patients with a food allergy at diagnosis was 6 months (1-156 months), and 71 patients (45.8%) were males. The median age of the control group was 12 months (1-61 months), and 67.0% were males. Older maternal age (P = 0.023), birth by caesarean section (P = 0.001), birth in the summer or autumn (P = 0.011), crowded housing (P = 0.001), damp houses (P = 0.001), being fed with breast milk and complementary food (P = 0.001), use of synthetic bedding (P = 0.024), and being the oldest child in the family (P = 0.001) were the considered risk factors for an immunoglobulin-E (IgE)-mediated food allergy. A low frequency of yoghurt consumption by mother (P = 0.001) and use of wool bedding (P = 0.018) were identified as risk factors for non-IgE-mediated food allergies. Low socioeconomic status (P = 0.001) played a protective role against both IgE- and non-IgE-mediated food allergies whereas breastfeeding played a protective role against IgE-mediated food allergies (P = 0.030). CONCLUSION: The most important aspect of this study was that it separately identified prenatal, neonatal, and postnatal risk factors for IgE- and non-IgE-mediated food allergies.

Neurologic Status of Patients with Purine Nucleoside Phosphorylase Deficiency Before and After Hematopoetic Stem Cell Transplantation.

BACKGROUND: Purine nucleoside phosphorylase (PNP) deficiency is a rare autosomal recessive combined immunodeficiency. The phenotype is profound T cell deficiency with variable B and NK cell functions and results in recurrent and persistent infections that typically begin in the first year of life. Neurologic findings occur in approximately two-thirds of patients. The mechanism of neurologic abnormalities is unclear. Hematopoietic stem cell transplantation (HSCT) is the only curative treatment for PNP deficiency. METHODS: We report here six patients from five unrelated families with PNP deficiency treated in two centers in Turkey. We evaluated the neurological status of patients and compared to post-transplantation period if available. Then, we performed PubMed, Google Scholar, and Researchgate searches using the terms "PNP" and "hematopoietic stem cell transplantation" to find all reported cases of PNP transplantation and compared to our cohort. RESULTS: Six patients were treated in two centers in Turkey. One patient died from post-transplant complications. The other four patients underwent successful HSCT with good immune reconstitution after transplantation (follow-up 21-48 months) and good neurological outcomes. The other patient with a new mutation is still waiting for a matching HLA donor. DISCUSSION: In PNP deficiency, clinical manifestations are variable, and this disease should be considered in the presence of many different clinical findings. Despite the comorbidities that occurred before transplantation, HSCT currently appears to be the only treatment option for this disease. HSCT not only cures immunologic disorders, but probably also improves or at least stabilizes the neurologic status of patients.