Search

Background: Chronic granulomatous disease (CGD), one of the phagocytic system defects, is the primary immunodeficiency caused by dysfunction of the NADPH oxidase complex which generates reactive oxygen species (ROS), which are essential for killing pathogenic microorganisms, especially catalase-positive bacteria and fungi. Objective: The objective of our study was to assess the clinical and laboratory characteristics, treatment modalities, and prognosis of patients with CGD. Methods: We retrospectively reviewed 63 patients with CGD who have been diagnosed, treated, and/or followed-up between 1984 and 2018 in Hacettepe University, Ankara, in Turkey, as a developing country. Results: The number of female and male patients was 26/37. The median age at diagnosis was 3.8 (IQR: 1.0–9.6) years. The rate of consanguinity was 63.5%. The most common physical examination finding was lymphadenopathy (44/63), growth retardation (33/63), and hepatomegaly (27/63). One adult patient had squamous cell carcinoma of the lung. The most common infections were lung infection (53/63), skin abscess (43/63), and lymphadenitis (19/63). Of the 63 patients with CGD, 6 patients had inflammatory bowel disease (IBD). Twelve of the 63 patients died during follow-up. CYBA, NCF1, CYBB, and NCF2 mutations were detected in 35%, 27.5%, 25%, and 12.5% of the patients, respectively. Conclusion: We identified 63 patients with CGD from a single center in Turkey. Unlike other cohort studies in Turkey, due to the high consanguineous marriage rate in our study group, AR form of CGD was more frequent, and gastrointestinal involvement were found at relatively lower rates. The rate of patients who treated with HSCT was lower in our research than in the literature. A majority of the patients in this study received conventional prophylactic therapies, which highlight on the outcome of individuals who have not undergone HSCT. [ABSTRACT FROM AUTHOR]

Background: Chronic granulomatous disease (CGD) is characterized by mutation in any one of the five genes coding NADPH oxidase components that leads to functional abnormality preventing the killing of phagocytosed microbes by affecting the progression of a respiratory burst. CGD patients have an increased susceptibility to infections by opportunistic and pathogenic organisms. Though initial diagnosis of CGD using a nitroblue tetrazolium (NBT) test or dihydrorhodamine (DHR) test is relatively easy, molecular diagnosis is challenging due to involvement of multiple genes, presence of pseudogenes, large deletions, and GC-rich regions, among other factors. The strategies for molecular diagnosis vary depending on the affected gene and the mutation pattern prevalent in the target population. There is a paucity of molecular data related to CGD for Indian population.Method: This report includes data for a large cohort of CGD patients (n = 90) from India, describing the diagnostic approach, mutation spectrum, and novel mutations identified. We have used mosaicism in mothers and the expression pattern of different NADPH components by flow cytometry as a screening tool to identify the underlying affected gene. The techniques like Sanger sequencing, next-generation sequencing (NGS), and Genescan analysis were used for further molecular analysis.Result: Of the total molecularly characterized patients (n = 90), 56% of the patients had a mutation in the NCF1 gene, 30% had mutation in the CYBB gene, and 7% each had mutation in the CYBA and NCF2 genes. Among the patients with NCF1 gene mutation, 82% of the patients had 2-bp deletion (DelGT) mutations in the NCF1 gene. In our cohort, 41 different mutations including 9 novel mutations in the CYBB gene and 2 novel mutations each in the NCF2, CYBA, and NCF1 genes were identified.Conclusion: Substantial number of the patients lack NCF1 gene on both the alleles. This is often missed by advanced molecular techniques like Sanger sequencing and NGS due to the presence of pseudogenes and requires a simple Genescan method for confirmation. Thus, the diagnostic approach may depend on the prevalence of affected genes in respective population. This study identifies potential gene targets with the help of flow cytometric analysis of NADPH oxidase components to design an algorithm for diagnosis of CGD in India. In Indian population, the Genescan method should be preferred as the primary molecular test to rule out NCF1 gene mutations prior to Sanger sequencing and NGS. [ABSTRACT FROM AUTHOR]

Interstitial lung disease (ILD) is a rare and heterogeneous group of disorder affecting the lung parenchyma and has a detrimental effect on gas exchange. Chronic granulomatous disease (CGD), when it affects primarily lungs, may cause ILD. We report a 16-year-old patient with CGD caused by homozygous deletion of NCF1 who atypically presented with ILD. The patient had many pigeons and was a pigeon breeder. Exacerbated clinical symptoms were linked to hypersensitivity pneumonitis (HP), and the patient was suggested to keep away from pigeons. In addition to allergen avoidance and prophylactic antibacterial therapy, treatment with corticosteroids and hydroxychloroquine was started for mainly obstructive and persistant symptoms of ILD. CGD is known to cause a hyperinflammatory state and the patients present with excessive granuloma formation and HP. Control of inflammation either by avoidance of allergen exposure and by anti-inflammatory drugs is necessary for the relief of symptoms. [ABSTRACT FROM AUTHOR]

Chronic granulomatous disease (CGD) is a rare congenital immune deficiency caused by mutations in any of the five genes encoding NADPH oxidase subunits. One of these genes is NCF1 , encoding the p47 phox protein. A group of 39 patients, 14 of whom are of Kavkazi Jewish descent, was investigated for a founder effect for the mutation c.579G > A ( p.Trp193Ter ) in NCF1 . We analyzed various genetic markers in the NCF1 region, including two single nucleotide polymorphisms (SNPs) in NCF1 and two short tandem repeats (STRs) located near NCF1 . Most patients were homozygous for the c.579G > A mutation, but three patients were hemizygotes, with a deletion of NCF1 on the other allele, and three patients were compound heterozygotes with another mutation in NCF1 . All Kavkazi Jewish patients had a c.295G_c.345T SNP combination in NCF1 and shared a common number of repeats in STR3. In addition, 90% of the Kavkazi Jewish patients shared a common number of repeats in STR1. This uniformity indicates that the c.579G > A mutation in NCF1 was introduced some 1200–2300 years ago in the Kavkazi Jewish population. Variation amongst the other investigated populations from the Middle East indicates that this mutation exists in these non-Kavkazi populations already for more than 5000 years. [ABSTRACT FROM AUTHOR]

Chronic granulomatous disease (CGD) is an immunodeficiency caused by defects in the nicotinamide adenine dinucleotide phosphate (NADPH)–oxidase complex and is usually diagnosed in early childhood. CGD patients suffer from severe, recurrent infections with bacteria, fungi and yeasts. We report a 25-year-old female with protracted fever because of a Staphylococcus aureus liver abscess, which did not resolve until breakthrough into the stomach. Despite her age, CGD was considered on diagnosis on the basis of the clinical symptoms. Analysis of the NADPH–oxidase activity confirmed CGD as the underlying condition. Western blotting revealed the absence of p47phox and subsequent sequencing of the p47phox-encoding gene, neutrophil cytosolic factor (NCF1), identified a deletion of 837C in the maternal NCF1 allele. The paternal allele contained a stopcodon because of a conversion between NCF1 and one of its ΨNCF1 pseudogenes. The patient had one novel mutation, c.837delC, and one conversion in NCF1, resulting in the complete absence of the p47phox component of the NADPH–oxidase complex. This p47phox-deficient CGD patient had the highest age at diagnosis reported thus far.Journal of Human Genetics (2009) 54, 313–316; doi:10.1038/jhg.2009.24; published online 27 March 2009 [ABSTRACT FROM AUTHOR]

Background: Chronic granulomatous disease (CGD) is a primary immune deficiency caused by mutations in the genes encoding the structural components of the phagocyte NADPH oxidase. As a result, the patients cannot generate sufficient amounts of reactive oxygen species required for killing pathogenic microorganisms. Methods: We analyzed NADPH oxidase activity and component expression in neutrophils, performed genomic DNA and cDNA analysis, and used mRNA splicing prediction tools to evaluate the impact of mutations. Results: In two patients with CGD, we had previously found mutations that cause aberrant pre‐mRNA splicing. In one patient an exonic mutation in a cryptic donor splice site caused the deletion of the 3' part of exon 6 from the mRNA of CYBB. This patient suffers from X‐linked CGD. The second patient, with autosomal CGD, has a mutation in the donor splice site of intron 1 of CYBA that activates a cryptic donor splice site downstream in intron 1, causing the insertion of intronic sequences in the mRNA. The third patient, recently analyzed, also with autosomal CGD, has a mutation in intron 4 of CYBA, 15 bp from the acceptor splice site. This mutation weakens a branch site and activates a cryptic acceptor splice site, causing the insertion of 14 intronic nucleotides into the mRNA. Conclusion: We found three different mutations, one exonic, one in a donor splice site and one intronic, that all caused missplicing of pre‐mRNA. We analyzed these mutations with four different splice prediction programs and found that predictions of splice site strength, splice enhancer and splice silencer protein binding and branch site strength are all essential for correct prediction of pre‐mRNA splicing. [ABSTRACT FROM AUTHOR]

Abstract: Chronic granulomatous disease (CGD) is an innate immunodeficiency due to a genetic defect in one of the NADPH-oxidase components. In the course of 21 years, 38 Israeli CGD patients were diagnosed with 17 gene mutations, seven of which were new. Clinical, functional, and molecular studies were accomplished. Although X-linked recessive (XLR)-CGD is worldwide the most common genotype of the disease (~70%), in our study only 11 patients (29%) suffered from XLR-CGD. In Israel, the higher incidence of the autosomal recessive (AR) form of CGD (63%) may be related to consanguineous marriages. In three patients (8%), all four proteins of the NADPH oxidase were present. Severe clinical expression was found both in the XLR and AR forms, but in general a milder disease was evident in AR-CGD, particularly in patients with p47phox deficiency. Despite early and aggressive therapy, a mortality rate of 26% was noted. Given that bone-marrow transplantation was successful in five of seven patients, it is recommended to perform it as early as possible before tissue damage is irreversible. [Copyright &y& Elsevier]

Biallelic loss-of-function (LOF) mutations of the NCF4 gene, encoding the p40phox subunit of the phagocyte NADPH oxidase, have been described in only 1 patient. We report on 24 p40phox-deficient patients from 12 additional families in 8 countries. These patients display 8 different in-frame or out-of-frame mutations of NCF4 that are homozygous in 11 of the families and compound heterozygous in another. When overexpressed in NB4 neutrophil-like cells and EBV-transformed B cells in vitro, the mutant alleles were found to be LOF, with the exception of the p.R58C and c.120_134del alleles, which were hypomorphic. Particle-induced NADPH oxidase activity was severely impaired in the patients' neutrophils, whereas PMA-induced dihydrorhodamine-1,2,3 (DHR) oxidation, which is widely used as a diagnostic test for chronic granulomatous disease (CGD), was normal or mildly impaired in the patients. Moreover, the NADPH oxidase activity of EBV-transformed B cells was also severely impaired, whereas that of mononuclear phagocytes was normal. Finally, the killing of Candida albicans and Aspergillus fumigatus hyphae by neutrophils was conserved in these patients, unlike in patients with CGD. The patients suffer from hyperinflammation and peripheral infections, but they do not have any of the invasive bacterial or fungal infections seen in CGD. Inherited p40phox deficiency underlies a distinctive condition, resembling a mild, atypical form of CGD. [ABSTRACT FROM AUTHOR]

Abstract: Chronic granulomatous disease (CGD) is a rare congenital disorder in which phagocytes cannot generate superoxide (O2 −) and other microbicidal oxidants due to mutations in one of the five components of the O2 −-generating NADPH oxidase complex. The most common autosomal subtype of CGD is caused by mutations in NCF1, encoding the NADPH subunit p47phox. Usually, these mutations are the result of unequal exchange of chromatid between NCF1 and one of its two pseudogenes. We have now investigated in detail the breakpoints within or between these (pseudo) NCF1 genes in 43 families with p47phox-deficient CGD by means of multiplex ligase-dependent probe amplification (MLPA). In 24 families the patients totally lacked NCF1 sequences, indicating that in these families the cross-over points are located between NCF1 and its pseudogenes. Six other families were compound heterozygous for a total NCF1 deletion and another mutation in NCF1 on the other allele. In 8 families, the patients lacked NCF1 exons 1–4 but had retained NCF1 exons 6–10, indicating that a cross-over point is located within NCF1 between exons 4 and 6. Similarly, in 4 families a cross-over point was located within NCF1 between exons 2 and 4. Similar cross-overs, in heterozygous form, were observed in family members of the patients. Several patients were compound heterozygous for total and partial NCF1 deletions. Thus, at least three different cross-over points exist within the NCF1 gene cluster, indicating that autosomal p47phox-deficient CGD is genetically heterogeneous but can be dissected in detail by MLPA. [Copyright &y& Elsevier]

Abstract: Chronic granulomatous disease (CGD) is an immunodeficiency disorder affecting about 1 in 250,000 individuals. The disease is caused by a lack of superoxide production by the leukocyte enzyme NADPH oxidase. Superoxide is used to kill phagocytosed micro-organisms in neutrophils, eosinophils, monocytes and macrophages. The leukocyte NADPH oxidase is composed of five subunits, of which the enzymatic component is gp91-phox, also called Nox2. This protein is encoded by the CYBB gene on the X chromosome. Mutations in this gene are found in about 70% of all CGD patients. This article lists all mutations identified in CYBB in the X-linked form of CGD. Moreover, apparently benign polymorphisms in CYBB are also given, which should facilitate the recognition of future disease-causing mutations. [ABSTRACT FROM AUTHOR]

Abstract: Chronic granulomatous Disease (CGD) is an immunodeficiency disorder affecting about 1 in 250,000 individuals. The disease is caused by mutations in the genes encoding the components of the leukocyte NADPH oxidase. This enzyme produces superoxide, which is essential in the process of intracellular pathogen killing by phagocytic leukocytes. Four of the five genes involved in CGD are autosomal; these are CYBA, encoding p22-phox, NCF2, encoding p67-phox, NCF1, encoding p47-phox, and NCF4, encoding p40-phox. This article lists all mutations identified in these genes in the autosomal forms of CGD. Moreover, polymorphisms in these genes are also given, which should facilitate the recognition of future disease-causing mutations. [Copyright &y& Elsevier]

Chronic granulomatous disease (CGD) is an immunodeficiency disorder affecting about 1 in 250,000 individuals. CGD patients suffer from severe, recurrent bacterial and fungal infections. The disease is caused by mutations in the genes encoding the components of the leukocyte NADPH oxidase. This enzyme produces superoxide, which is subsequently metabolized to hydrogen peroxide and other reactive oxygen species (ROS). These products are essential for intracellular killing of pathogens by phagocytic leukocytes (neutrophils, eosinophils, monocytes and macrophages). The leukocyte NADPH oxidase is composed of five subunits, four of which are encoded by autosomal genes. These are CYBA , encoding p22phox, NCF1 , encoding p47phox, NCF2 , encoding p67phox and NCF4 , encoding p40phox. This article lists all mutations identified in these genes in CGD patients. In addition, cytochrome b 558 chaperone-1 (CYBC1), recently recognized as an essential chaperone protein for the expression of the X-linked NADPH oxidase component gp91phox (also called Nox2), is encoded by the autosomal gene CYBC1. Mutations in this gene also lead to CGD. Finally, RAC2, a small GTPase of the Rho family, is needed for activation of the NADPH oxidase, and mutations in the RAC2 gene therefore also induce CGD-like symptoms. Mutations in these last two genes are also listed in this article. [ABSTRACT FROM AUTHOR]

Chronic granulomatous disease (CGD) is an immunodeficiency disorder affecting about 1 in 250,000 individuals. CGD patients suffer from severe bacterial and fungal infections. The disease is caused by a lack of superoxide production by the leukocyte enzyme NADPH oxidase. Superoxide and subsequently formed other reactive oxygen species (ROS) are instrumental in killing phagocytosed micro-organisms in neutrophils, eosinophils, monocytes and macrophages. The leukocyte NADPH oxidase is composed of five subunits, of which the enzymatic component is gp91phox, also called Nox2. This protein is encoded by the CYBB gene on the X chromosome. Mutations in this gene are found in about 70% of all CGD patients in Europe and in about 20% in countries with a high ratio of parental consanguinity. This article lists all mutations identified in CYBB and should therefore help in genetic counseling of X-CGD patients' families. Moreover, apparently benign polymorphisms in CYBB are also given, which should facilitate the recognition of disease-causing mutations. In addition, we also include some mutations in G6PD , the gene on the X chromosome that encodes glucose-6-phosphate dehydrogenase, because inactivity of this enzyme may lead to shortage of NADPH and thus to insufficient activity of NADPH oxidase. Severe G6PD deficiency can induce CGD-like symptoms. [ABSTRACT FROM AUTHOR]