Chronic granulomatous disease in the United Arab Emirates: clinical and molecular characteristics in a single center.

Background: Chronic granulomatous disease (CGD) is a genetic disorder caused by defective oxidative burst within phagocytes, manifesting as recurrent, severe infections as well as hyperinflammation. Objective: This is the first report from the United Arab Emirates (UAE) to describe the demographic, clinical, laboratory, radiological, and genetic characteristics of patients with CGD. Methods: This is a retrospective study that was conducted at Tawam Hospital in the UAE on patients with confirmed CGD between 2017 and 2022. Results: A total of 14 patients were diagnosed with CGD, of whom 13 patients had autosomal recessive (AR) CGD due to NCF1 deficiency. Consanguinity was noted in all patients with AR CGD, whereas positive family history was identified in 50% of cases. The median age of onset of symptoms was 24 months, while the median age at diagnosis was 72 months. Lymphadenitis was the most common clinical feature identified in 71% of patients. Other common infectious manifestations included abscess formation (57%), pneumonia (50%), invasive aspergillosis (21%), oral thrush (14%), and sepsis (14%). Disseminated trichosporonosis was reported in one patient. Autoimmune and inflammatory manifestations included celiac disease in two patients, diabetes mellitus and asymptomatic colitis in one patient each. Genetic analysis was performed in all patients; NCF1 deficiency was diagnosed in 13 (93%) patients, with c.579G>A being the most prevalent pathogenic variant identified. The treatment modalities, as well as treatment of acute infections, treatment modalities included antimicrobial prophylaxis in 12 (86%) patients and hematopoietic stem cell transplant in six patients (42%). Conclusion: This is the first report from the UAE describing the clinical and molecular characteristics of patients with CGD. The homozygous variant c.579G>A causing NCF1 deficiency can be considered as a founder mutation for AR CGD in the UAE.

Good outcome of the single-center pediatric kidney transplant program in Abu Dhabi.

Renal transplantation is the treatment of choice for ESRD in children. It is associated with better quality of life, growth of children, and improved long-term survival. The aim of the study was to evaluate the outcomes of pediatric renal transplantation at a tertiary care center in UAE. A retrospective chart review was undertaken for all the pediatric renal transplants performed at Sheikh Khalifa Medical City, Abu Dhabi, UAE, over the past 9 years. The study evaluated the demographic data, outcomes, and complications of pediatric renal transplantation. The post-transplantation outcomes including surgical complications, documented infections, graft rejection, graft and patient survival, effect on growth, and eGFR were reviewed. Between 2010 and 2018, 30 pediatric patients underwent renal transplantation. The follow-up period ranged from 1 to 9 years with a mean of 3.3 years. The mean age of the patients at the time of transplant was 9.8 years, and 56.7% were males. Prior to the transplantation, the majority of the recipients were on peritoneal dialysis (70.0%). Main source of renal donation at our center was from LRD, chiefly from parents. Patient survival at 1 and 5 years was 100% and 96.7%, respectively. Graft survival at 1 and 5 years was 96.7% and 83.3%, respectively. During the 9-year follow-up period, 5 (16.7%) recipients experienced rejection episode. This study demonstrates that during 5-year period, pediatric kidney transplantation program has achieved optimal patient (96.7%) and graft (83.3%) survival rates and is comparable to well-established centers.

Frequency of rs731236 (Taql), rs2228570 (Fok1) of Vitamin-D Receptor (VDR) gene in Emirati healthy population.

Vitamin D is getting more attention everyday due to its importance in maintaining bone and calcium homeostasis, cellular proliferation, differentiation and immune response. Vitamin D is derived from diet or elicited in the skin by the activation of 7-dehydrocholesterol, which is an inert molecule that must be activated by ultraviolet light to form pre-vitamin D3. Recent studies connected the gene encoding for vitamin D (VDR) to the genetic control of bone mass and other diseases. As VDR SNPs have been associated with several disorders and diseases, it's important to investigate the allelic and genotypic distribution among populations. The aim of this study is to determine the frequency of rs731236 (Taq1) and rs2228570 (Fok1) variants in healthy Emirati individuals and compare their genotype and allele distribution with other populations. In this study 282 (female, 187; male, 95) unrelated healthy UAE nationals were involved. Two hundreds and eight two DNA samples been collected to genotype rs731236 (Taq1) and rs2228570 (Fok1) VDR SNPs. Our results indicate that the distribution of the alleles and genotypes of rs731236 (Taq1) and rs2228570 (Fok1) vary considerably in different populations. In the Emirati population the distribution of rs731236 (Taq1) and rs2228570 (Fok1) were AA 38%, AG 42%, GG 20% and AA 27%, AG 42%, GG 31% respectively. The Emirati population genotype and allele distribution of rs731236 (Taq1) and rs2228570 (Fok1) had no difference with Caucasians from USA and France. However, there was significant difference with Asian populations.

Raised plasma insulin level and homeostasis model assessment (HOMA) score in cerebral malaria: evidence for insulin resistance and marker of virulence.

OBJECTIVE: To study the glycaemic profile of patients with severe malaria (SM). METHODS: For this purpose, 110 SM patients were recruited. Pre-treatment random blood glucose and plasma insulin were measured in a subset of donors. An ex-vivo experiment was developed for estimation of glucose consumption by parasitized erythrocytes. RESULTS: Hyperglycaemia was frequent in SM but more commonly associated with cerebral malaria (CM), while hyperinsulinaemia was recognized in severe-malarial-hypotension (median, 25 %-75 %, 188.2, 93.8-336.8 pmol/L). The plasma insulin level was positively correlated with age (CC = 0.457, p < 0.001) and negatively with parasitaemia (CC = -0.368, p = 0.045). Importantly, fatal-CM was associated with hyperglycaemia (12.22, 6.5-14.6 mmol/L), hyperinsulinaemia (141.0, 54.0-186.8 pmol/L) and elevated homeostasis model assessment (HOMA) values. However, there was a trend of higher glucose consumption by parasites in CM compared with that in uncomplicated malaria (UM). CONCLUSION: Hyperglycaemia, hyperinsulinaemia and elevated HOMA are evidence for insulin resistance and possibly pancreatic B-cell dysfunction in fatal-CM.

Munc18-2 deficiency causes familial hemophagocytic lymphohistiocytosis type 5 and impairs cytotoxic granule exocytosis in patient NK cells.

Familial hemophagocytic lymphohistiocytosis (FHL) is a genetically heterogeneous autosomal recessive immune disorder characterized by the occurrence of uncontrolled activation of lymphocytes and macrophages infiltrating multiple organs. Disease-causing mutations in the perforin (PRF1; also known as FHL2), Munc13-4 (UNC13D; also known as FHL3), and syntaxin-11 (STX11; also known as FHL4) genes have been identified in individuals with FHL. These genes all encode proteins involved in the cytotoxic activity of lymphocytes. Here, we show that the gene encoding syntaxin-binding protein 2 (Munc18-2; official gene symbol STXBP2) is mutated in another subset of patients with FHL (designated by us as "FHL5"). Lymphoblasts isolated from these patients had strongly decreased STXBP2 protein expression, and NK cells exhibited impaired cytotoxic granule exocytosis, a defect that could be overcome by ectopic expression of wild-type STXBP2. Furthermore, we provide evidence that syntaxin-11 is the main partner of STXBP2 in lymphocytes, as its expression required the presence of STXBP2. Our work shows that STXBP2 deficiency causes FHL5. These data indicate that STXBP2 is required at a late step of the secretory pathway for the release of cytotoxic granules by binding syntaxin 11, another component of the intracellular membrane fusion machinery.