Chronic Granulomatous Disease

Diagnosis of Chronic Granulomatous Disease: Strengths and Challenges in the Genomic Era

Chronic granulomatous disease (CGD) is a group of rare primary inborn errors of immunity characterised by a defect in the phagocyte respiratory burst, which leads to severe and life-threatening infective and inflammatory complications. Despite recent advances in our understanding of the genetic and molecular pathophysiology of X-linked and autosomal recessive CGD, and growth in the availability of functional and genetic testing, there remain significant barriers to early and accurate diagnosis. In the current review, we provide an up-to-date summary of CGD pathophysiology, underpinning current methods of diagnostic testing for CGD and closely related disorders. We present an overview of the benefits of early diagnosis and when to suspect and test for CGD. We discuss current and historical methods for functional testing of NADPH oxidase activity, as well as assays for measuring protein expression of NADPH oxidase subunits. Lastly, we focus on genetic and genomic methods employed to diagnose CGD, including gene-targeted panels, comprehensive genomic testing and ancillary methods. Throughout, we highlight general limitations of testing, and caveats specific to interpretation of results in the context of CGD and related disorders, and provide an outlook for newborn screening and the future.

Imaging Findings in Chronic Granulomatous Disease (CGD)

OBJECTIVES

To describe prevalence of various imaging findings in chronic granulomatous disease (CGD) patients; and find imaging biomarkers for differentiating chest infections caused by different micro-organisms.

METHODS

A retrospective study was conducted on 15 patients (49 scans) with proven CGD. Scans which had a correlative microbiological diagnosis for organisms were included in the analysis. The scans were reviewed by 3 radiologists on a predefined proforma, under the lung parenchymal, airway, pleural, mediastinal, and extrathoracic abnormalities. Analysis of various imaging parameters on a semiquantitative scale was performed, followed by a correlation of each imaging findings with causative organisms.

RESULT

The mean age of presentation was nearly 7 y, with a male preponderance. Definitive proof of causative organisms was obtained in 22 scans. Bacterial infection was found in 7, fungal in 12, tubercular in 2, and viral in 1 scan. Most prevalent thoracic imaging manifestations included lymphadenopathy (commonest), consolidation, nodules, air trapping, and bronchiectasis. Fungal infections showed necrotic conglomerate lymphadenopathy, cavitating nodules, and multilobar consolidation more frequently than bacterial infections (though not statistically significant). Abscesses and lymphadenopathy were the most common extrathoracic manifestations.

CONCLUSION

In patients with CGD, multifocal or multilobar consolidation, mass-like consolidation, cavitating nodules, and conglomerate necrotic lymphadenopathy should alert the radiologist to a possible fungal cause.

A variety of death modes of neutrophils and their role in the etiology of autoimmune diseases

Neutrophils are important in the context of innate immunity and actively contribute to the progression of diverse autoimmune disorders. Distinct death mechanisms of neutrophils may exhibit specific and pivotal roles in autoimmune diseases and disease pathogenesis through the orchestration of immune homeostasis, the facilitation of autoantibody production, the induction of tissue and organ damage, and the incitement of pathological alterations. In recent years, more studies have provided in-depth examination of various neutrophil death modes, revealing nuances that challenge conventional understanding and underscoring their potential clinical utility in diagnosis and treatment. This review explores the multifaceted processes and characteristics of neutrophil death, with a focus on tailored investigations within various autoimmune diseases. It also highlights the potential interplay between neutrophil death and the landscape of autoimmune disorders. The review encapsulates the pertinent pathways implicated in various neutrophil death mechanisms across diverse autoimmune diseases while also charts possible avenues for future research.

Septic Transfusion Reactions Involving Burkholderia cepacia Complex: A Review

This review was conducted to assess the global incidence of transfusion-transmitted infections (TTIs) caused by contamination of blood components with the Burkholderia cepacia complex (Bcc). Our search encompassed various specialized databases such as Medline/PubMed, Web of Science, Scopus, Scielo, ScienceDirect, and ClinicalKey. An analysis of the literature revealed a total of eleven reported cases where blood components contaminated with Bcc had been transfused, resulting in sepsis among the affected patients. Of these cases, eight were documented in the literature, while the remaining three occurred within the institution involving the authors of this review. A comparative examination was conducted, considering factors such as primary diagnosis, transfused blood component, time elapsed between transfusion and manifestation of symptoms, administration of antibiotics, and final outcome. Interestingly, regardless of the storage temperature, all blood components were found to be susceptible to Bcc contamination. Furthermore, the cases investigated revealed diverse sources of contamination, and it was observed that all the affected patients had compromised immune systems due to underlying illnesses. Based on these findings, a series of preventive strategies were derived to mitigate and decrease the occurrence of similar cases.

Cystic fibrosis autoantibody signatures associate with Staphylococcus aureus lung infection or cystic fibrosis-related diabetes

Introduction

While cystic fibrosis (CF) lung disease is characterized by persistent inflammation and infections and chronic inflammatory diseases are often accompanied by autoimmunity, autoimmune reactivity in CF has not been studied in depth.

Methods

In this work we undertook an unbiased approach to explore the systemic autoantibody repertoire in CF using autoantibody microarrays.

Results and discussion

Our results show higher levels of several new autoantibodies in the blood of people with CF (PwCF) compared to control subjects. Some of these are IgA autoantibodies targeting neutrophil components or autoantigens linked to neutrophil-mediated tissue damage in CF. We also found that people with CF with higher systemic IgM autoantibody levels have lower prevalence of S. aureus infection. On the other hand, IgM autoantibody levels in S. aureus-infected PwCF correlate with lung disease severity. Diabetic PwCF have significantly higher levels of IgA autoantibodies in their circulation compared to nondiabetic PwCF and several of their IgM autoantibodies associate with worse lung disease. In contrast, in nondiabetic PwCF blood levels of IgA autoantibodies correlate with lung disease. We have also identified other autoantibodies in CF that associate with P. aeruginosa airway infection. In summary, we have identified several new autoantibodies and associations of autoantibody signatures with specific clinical features in CF.

Sputum from People with Cystic Fibrosis Reduces the Killing of Methicillin-Resistant Staphylococcus aureus by Neutrophils and Diminishes Phagosomal Production of Reactive Oxygen Species

Cystic fibrosis (CF) airway disease is characterized by chronic polymicrobial infections and an infiltration of neutrophils (PMNs). Staphylococcus aureus has been the most prevalent respiratory pathogen in CF. In particular, methicillin-resistant S. aureus (MRSA) represents a huge clinical burden in CF due to its association with lung disease and increased resistance to antibiotics. In CF, PMNs are unable to kill and clear MRSA. The reason for this remains largely unknown. Our study found that CF PMNs are as equally capable of killing MRSA as healthy PMNs. We show that the CF sputum, however, significantly impairs the ability of human PMNs to kill CF MRSA isolates. In the absence of CF sputum, PMNs kill MRSA via intracellular mechanisms mediated by phagocytosis, rather than extracellular mechanisms via NET formation. CF sputum does not affect the phagocytosis of MRSA via healthy or CF PMNs. Our results demonstrate that CF sputum exposure impairs phagosomal levels of reactive oxygen species (ROS) in MRSA-phagocytosing PMNs. While phagosomal co-localizations of MRSA with primary granule markers, myeloperoxidase and cathepsin D, were significantly reduced upon CF sputum exposure, that of a third azurophilic granule marker, neutrophil elastase, remained unaffected. This suggests that CF sputum does not compromise the fusion of primary granules with phagosomes but diminishes phagosomal ROS levels via another, likely more specific, mechanism. Overall, we identified the airway environment as an important factor that restricts neutrophils' oxidative microbicidal activities in CF against MRSA. These results deliver new details of the complex host-pathogen interactions present in the CF lung.

R, Eley B, Bhattad S. Genetically confirmed chronic granulomatous disease in a Kenyan child: case report

Introduction

We report the first case of genetically confirmed chronic granulomatous disease (CGD) in a Kenyan child.

Clinical findings

A 7-month-old male infant, the only child of non-consanguineous parents, presented with cough, fever, fast breathing, oral thrush, and axillary lymphadenopathy ipsilateral to the Calmette-Guérin bacillus scar. He had been hospitalized 5 weeks prior for severe pneumonia. Plain chest radiography showed bilateral patchy airspace opacification; chest computed tomography revealed multiple large lung nodules and left axillary lymphadenopathy. HIV ELISA was negative; tuberculin skin test was positive; lymph node biopsy macroscopically revealed caseous granulomas seen on histology; isoniazid- and rifampicin-susceptible Mycobacterium tuberculosis complex isolate was detected on the Hain test. First-line anti-tuberculous drugs were added to his empiric treatment comprising piperacillin-tazobactam, amikacin, cotrimoxazole, and fluconazole. He was discharged after 10 days based on clinical resolution.

Diagnoses interventions and outcome

An inborn error of immunity (IEI) was considered given the recurrent fevers and atypical lung nodules. Genetic analysis revealed a hemizygous pathogenic variant on CYBB in keeping with X-linked CGD. The child's fevers recurred 2 weeks post-discharge but completely resolved on prophylactic itraconazole and cotrimoxazole. He underwent a successful haplo-identical hematopoietic stem cell transplantation at an experienced center in India with his father as the donor and is currently doing well on post-transplant follow-up.

Conclusion

Genetic testing is relatively accessible and cost-effective for the diagnosis of IEI in low-and-middle-income countries. Expert multi-disciplinary collaboration is key for successful outcomes.

The Multiple Faces of Nitric Oxide in Chronic Granulomatous Disease: A Comprehensive Update

Nitric oxide (NO), a signaling molecule, regulates multiple biological functions, including a variety of physiological and pathological processes. In this regard, NO participates in cutaneous inflammations, modulation of mitochondrial functions, vascular diseases, COVID-19, neurologic diseases, and obesity. It also mediates changes in the skeletal muscle function. Chronic granulomatous disease (CGD) is a primary immunodeficiency disorder characterized by the malfunction of phagocytes caused by mutations in some of the genes encoding subunits of the superoxide-generating phagocyte NADPH (NOX). The literature consulted shows that there is a relationship between the production of NO and the NADPH oxidase system, which regulates the persistence of NO in the medium. Nevertheless, the underlying mechanisms of the effects of NO on CGD remain unknown. In this paper, we briefly review the regulatory role of NO in CGD and its potential underlying mechanisms.

Long-Term Observational Study of Chronic Granulomatous Disease About 41 Patients From Tunisia and Comparison to Other Long-Term Follow-Up Studies

Chronic granulomatous disease (CGD) is an inherited autosomal recessive or X-Linked primitive immunodeficiency (PID), due to a defective nicotinamide adenine dinucleotide phosphate (NADPH) oxidase complex impairing anti-infectious and anti-inflammatory role of peripheral blood mononuclear cells. It is characterized by severe bacterial and fungal infections and by excessive inflammation leading to granulomatous complications. This work was made over a period of 34 years on 41 Tunisian patients suffering from CGD. Cumulative follow-up of patients was 2768.5 months, median 31 months. Survival was studied by survival curves according to Kaplan-Meier method. Lymphatic nodes, pulmonary and cutaneous infections predominate as revealing manifestations and as infectious events during patients' monitoring. At study end 12 patients died mainly of invasive pulmonary aspergillosis and septicemia. Median age of death was 30 months. CGD remains compatible with a decent quality of life. Early diagnosis, anti-infectious prophylaxis, and initiation of adequate management, as soon as complication is perceived, promote pretty good evolution.

A 31-Year-Old Man With Seizures, Brain Lesion, and Lung Nodules

CASE PRESENTATION

A 31-year-old man was admitted to our hospital with a recent history of generalized seizures. Three months earlier, he started with intermittent hemoptysis. CT scan showed a cavitary lung lesion in the upper segment of the right inferior lobe (RIL). Because of his job as a social worker in a high-risk population, he started treatment for Mycobacterium TB; however, the BAL culture result was negative. At the time of his current admission, he has continued taking rifampicin, isoniazid, pyrazinamide, and levofloxacin. He denied the use of any illicit drugs or alcohol. He had no history of smoking. One year earlier, he visited Southeast Asia, Oceania, and South Africa for several months. He reported a weight loss of 7 kg since then. Except for a recurrent oral candidiasis, he did not have a relevant medical history. His family history was notable for mother with lupus, and brother with sarcoidosis.

Nocardia cyriacigeorgica Brain and Lung Abscesses in 77-Year-Old Man With Diabetes

Nocardia species are difficult to identify, saprophytic, aerobic actinomycetes that are associated with high mortality rates and primarily affect immunocompromised hosts. Recently, the number ofdiagnoses of Nocardia cyriacigeorgica has grown in the United States, yet complicated clinical diagnosis and costly identification methods presume an underestimation of its presence in patients. We describe a case of brain abscess secondary to a pulmonary infection in an elderly, diabetic, Afghani man with an extensive history of chewing tobacco use.

Hematologically important mutations: The autosomal forms of chronic granulomatous disease (third update)

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 p22^phox, NCF1, encoding p47^phox, NCF2, encoding p67^phox and NCF4, encoding p40^phox. This article lists all mutations identified in these genes in CGD patients. In addition, cytochrome b₅₅₈ chaperone-1 (CYBC1), recently recognized as an essential chaperone protein for the expression of the X-linked NADPH oxidase component gp91^phox (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.

Cystic Fibrosis Sputum Impairs the Ability of Neutrophils to Kill Staphylococcus aureus

Cystic fibrosis (CF) airway disease is characterized by chronic microbial infections and infiltration of inflammatory polymorphonuclear (PMN) granulocytes. Staphylococcus aureus (S. aureus) is a major lung pathogen in CF that persists despite the presence of PMNs and has been associated with CF lung function decline. While PMNs represent the main mechanism of the immune system to kill S. aureus, it remains largely unknown why PMNs fail to eliminate S. aureus in CF. The goal of this study was to observe how the CF airway environment affects S. aureus killing by PMNs. PMNs were isolated from the blood of healthy volunteers and CF patients. Clinical isolates of S. aureus were obtained from the airways of CF patients. The results show that PMNs from healthy volunteers were able to kill all CF isolates and laboratory strains of S. aureus tested in vitro. The extent of killing varied among strains. When PMNs were pretreated with supernatants of CF sputum, S. aureus killing was significantly inhibited suggesting that the CF airway environment compromises PMN antibacterial functions. CF blood PMNs were capable of killing S. aureus. Although bacterial killing was inhibited with CF sputum, PMN binding and phagocytosis of S. aureus was not diminished. The S. aureus-induced respiratory burst and neutrophil extracellular trap release from PMNs also remained uninhibited by CF sputum. In summary, our data demonstrate that the CF airway environment limits killing of S. aureus by PMNs and provides a new in vitro experimental model to study this phenomenon and its mechanism.

Hematologically important mutations: X-linked chronic granulomatous disease (fourth update)

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 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 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.

Liver Abscess in Chronic Granulomatous Disease-Two Decades of Experience from a Tertiary Care Centre in North-West India

PURPOSE

Most of the literature on liver abscess in chronic granulomatous disease (CGD) emanates from developed countries. Data from developing countries are scarce. In this study, we report clinical features, microbiological profile, and treatment difficulties encountered while managing liver abscesses in patients with CGD at a tertiary care centre in North-West India.

METHODOLOGY

Case records of children with CGD and liver abscesses at Pediatric Immunodeficiency Clinic, Advanced Pediatrics Centre, Postgraduate Institute of Medical Education and Research, Chandigarh, India were analyzed.

RESULTS

Seven of 68 patients (10.29%) with CGD presented with hepatic abscess. One patient had 2 recurrences. All were males and age-range at presentation was 7 months-22 years. Mutation analysis was carried out in all patients-3 had defects in CYBB gene; 2 in NCF1; 2 in NCF2 gene. Staphylococcus aureus was isolated from 5 patients. Duration of antimicrobial treatment ranged from 3 weeks to 7 months. Open drainage was required in 1 patient, and 1 patient was treated with a prolonged course of prednisolone. Two children succumbed to the illness.

CONCLUSIONS

This is the largest reported experience of liver abscesses in patients with CGD from the developing world. Staphylococcus aureus was the commonest pathogen isolated. In our experience, prolonged courses of antimicrobials are usually necessary in these patients. Glucocorticoids can reduce inflammatory response and facilitate early resolution of abscesses in CGD.

Granulocyte-targeted therapies for airway diseases

The average respiration rate for an adult is 12-20 breaths per minute, which constantly exposes the lungs to allergens and harmful particles. As a result, respiratory diseases, which includes asthma, chronic obstructive pulmonary disease (COPD) and acute lower respiratory tract infections (LTRI), are a major cause of death worldwide. Although asthma, COPD and LTRI are distinctly different diseases with separate mechanisms of disease progression, they do share a common feature - airway inflammation with intense recruitment and activation of granulocytes and mast cells. Neutrophils, eosinophils, basophils, and mast cells are crucial players in host defense against pathogens and maintenance of lung homeostasis. Upon contact with harmful particles, part of the pulmonary defense mechanism is to recruit these cells into the airways. Despite their protective nature, overactivation or accumulation of granulocytes and mast cells in the lungs results in unwanted chronic airway inflammation and damage. As such, understanding the bright and the dark side of these leukocytes in lung physiology paves the way for the development of therapies targeting this important mechanism of disease. Here we discuss the role of granulocytes in respiratory diseases and summarize therapeutic strategies focused on granulocyte recruitment and activation in the lungs.

Flow Cytometry for Diagnosis of Primary Immune Deficiencies-A Tertiary Center Experience From North India

Flow cytometry has emerged as a useful technology that has facilitated our understanding of the human immune system. Primary immune deficiency disorders (PIDDs) are a heterogeneous group of inherited disorders affecting the immune system. More than 350 genes causing various PIDDs have been identified. While the initial suspicion and recognition of PIDDs is clinical, laboratory tools such as flow cytometry and genetic sequencing are essential for confirmation and categorization. Genetic sequencing, however, are prohibitively expensive and not readily available in resource constrained settings. Flow cytometry remains a simple, yet powerful, tool for multi-parametric analysis of cells. While it is confirmatory of diagnosis in certain conditions, in others it helps in narrowing the list of putative genes to be analyzed. The utility of flow cytometry in diagnosis of PIDDs can be divided into four major categories: (a) Enumeration of lymphocyte subsets in peripheral blood. (b) Detection of intracellular signaling molecules, transcription factors, and cytokines. (c) Functional assessment of adaptive and innate immune cells (e.g., T cell function in severe combined immune deficiency and natural killer cell function in familial hemophagocytic lymphohistiocytosis). (d) Evaluation of normal biological processes (e.g., class switching in B cells by B cell immunophenotyping). This review focuses on use of flow cytometry in disease-specific diagnosis of PIDDs in the context of a developing country.

Clinical and Molecular Features of Chronic Granulomatous Disease in Mainland China and a XL-CGD Female Infant Patient After Prenatal Diagnosis

PURPOSE

Chronic granulomatous disease (CGD) is the most common phagocyte defect disease. Here, we describe 114 CGD patients in our center and report a rare female infant with XL-CGD to provide a better understanding of diagnosis, treatment, and prenatal diagnosis of CGD.

METHOD

Patients were diagnosed by DHR-1,2,3 flow cytometry assays and gene analysis. X chromosome inactivation analysis and gp91^phox protein test were used for a female infant with XL-CGD.

RESULTS

XL-CGD accounts for the majority of cases in China and results in higher susceptibility to some infections than AR-CGD. The DHR assay can help diagnose CGD quickly, and atypical results should be combined with clinical manifestations, genetic analysis, and regular follow-up. For prenatal diagnosis, both gDNA and cDNA genotypes of amniotic fluid cells should be identified, and cord blood DHR assays should be performed to identify female XL-CGD patients.

Infection Profile in Chronic Granulomatous Disease: a 23-Year Experience from a Tertiary Care Center in North India

PURPOSE

Chronic granulomatous disease (CGD) is an inherited phagocytic disorder characterized by recurrent infections with usually catalase-positive organisms. Infections in CGD from developing countries are expected to be different from those in the Western countries. We report the profile of infections in children diagnosed with CGD from a tertiary care center in North India.

METHODOLOGY

Case records of children diagnosed with CGD at Pediatric Immunodeficiency Clinic, Advanced Pediatrics Centre, Postgraduate Institute of Medical Education and Research, Chandigarh, India, from August 1993 to April 2016 (23 years) were analyzed.

RESULTS

Thirty-eight children were diagnosed to have CGD. Median follow-up of patients was 2 years (interquartile range 0.75, 6.0). Staphylococcus aureus and Pseudomonas spp. were the two most common causative bacteria isolated. Aspergillus was the most common fungus isolated. The most common organ involved was the lung (94.7%). Liver abscesses were identified in 5 patients (13.2%), and 20 (52.6%) patients had lymphadenitis. Infections with Pseudomonas spp. were high in our cohort (15.7%) compared to the other studies. Infections with some unusual organisms (e.g., Fusarium dimerium and Chryseobacterium gleum) were also seen in our cohort. Children with X-linked CGD presented earlier and also had a greater number of infections as compared to autosomal recessive CGD.

CONCLUSIONS

Various socioeconomic factors coupled with the lack of awareness and paucity of readily available diagnostic facilities for primary immunodeficiencies accounted for a late clinical presentation with severe infections and increased mortality (28.9%) in our cohort. However, mortality was similar in X-linked and autosomal recessive CGD as was the number of fungal infections. The incidence of infections and mortality was significantly lower after initiation of antibacterial and antifungal prophylaxis.

An Uncommon Feature of Chronic Granulomatous Disease in a Neonate

Chronic Granulomatous Disease (CGD) represents recurrent life-threatening bacterial and fungal infections and granuloma formation with a high mortality rate. CGD's sign and symptoms usually appear in infancy and children before the age of five; therefore, its presentation in neonatal period with some uncommon features may be easily overlooked. Here we describe a case of CGD in a 24-day-old boy, presenting with a diffuse purulent vesiculopustular rash and multiple osteomyelitis.