Recurrent Bacterial Infections Research Articles

Transcriptome profiling of regulatory T cells from children with transient hypogammaglobulinemia of infancy.

Transient hypogammaglobulinemia of infancy (THI) is one of the most common forms of hypogammaglobulinemia in the early childhood. THI is usually associated with chronic, recurrent bacterial and viral infections, life-threatening in some cases, yet its pathogenesis is still largely unknown. As our previous findings indicated the possible role of Treg cells in the pathomechanism of THI, the aim of the current study was to investigate gene expression profile of Treg cells isolated from THI patients. The transcriptome-wide gene profiling was performed using microarray technology on THI patients in two time-points: during (THI-1), and in resolution phase (THI-2) of hypogammaglobulinemia. As a result, a total of 1086 genes were differentially expressed in THI-1 patients, when compared to THI-2 as well as control group. Among them, 931 were up- and 155 downregulated, and part of them encodes genes important for Treg lymphocyte biology and function, i.e. transcription factors/cofactors that regulate FOXP3 expression. Thus, we postulate that Treg cells isolated from THI patients during hypogammaglobulinemia display enhanced suppressor transcriptome signature. Treg expression profile of THI children after normalization of Ig levels largely resembles the results obtained in healthy control group, suggesting THI Treg transcriptome seems to return to that observed in healthy children. Taken together, we suggest that THI pathomechanism is associated not only with transiently elevated Treg cell numbers, but also with their enhanced regulatory/inhibitory functions. These findings expand our knowledge of human Treg cells and may be useful for the future diagnosis or management of THI.

Matrix-Mediated Delivery of Silver Nanoparticles for Prevention of Staphylococcus aureus and Pseudomonas aeruginosa Biofilm Formation in Chronic Rhinosinusitis.

Chronic rhinosinusitis (CRS) is a chronic health condition affecting the sinonasal cavity. CRS-associated mucosal inflammation leads to sinonasal epithelial cell death and epithelial cell barrier disruption, which may result in recurrent bacterial infections and biofilm formation. For patients who fail medical management and elect endoscopic sinus surgery for disease control, bacterial biofilm formation is particularly detrimental, as it reduces the efficacy of surgical intervention. Effective treatments that prevent biofilm formation in post-operative patients in CRS are currently limited. To address this unmet need, we report the controlled release of silver nanoparticles (AgNps) with silk-elastinlike protein-based polymers (SELPs) to prevent bacterial biofilm formation in CRS. This polymeric network is liquid at room temperature and forms a hydrogel at body temperature, and is hence, capable of conforming to the sinonasal cavity upon administration. SELP hydrogels demonstrated sustained AgNp and silver ion release for the studied period of three days, potent in vitro antibacterial activity against Pseudomonas aeruginosa (**** p < 0.0001) and Staphylococcus aureus (**** p < 0.0001), two of the most commonly virulent bacterial strains observed in patients with post-operative CRS, and high cytocompatibility with human nasal epithelial cells. Antibacterial controlled release platform shows promise for treating patients suffering from prolonged sinonasal cavity infections due to biofilms.

Cyclic Neutropenia Mimicking Crohn's Disease: Two Case Reports and a Narrative Review.

Cyclic neutropenia is a rare hematological condition characterized by periodic fluctuations in neutrophil counts, with a 21-day periodicity. Clinical presentation varies from mild to severe forms of the disease, with the onset of recurrent fever, painful oral ulcers, recurrent bacterial infections, peritonitis, and septic shock. The availability of granulocyte colony-stimulating factor (G-CSF) has revolutionized the management and natural history of this disease, regulating the proliferation, differentiation, and maturation of the progenitor cells, and reducing the duration of neutropenia. Inflammatory bowel disease (IBD), including Crohn's disease (CD) and ulcerative colitis (UC), is a group of chronic pathologies that affect the gastrointestinal tract. The onset of both diseases may be at a young age (even during childhood or adolescence), and clinical manifestations may lead to misdiagnosis, due to similar characteristics such as recurrent infections, oral ulcers, perianal abscesses, and infertility. Moreover, the two pathologies are rarely associated, with different management and therapeutic options. Here, we describe two case reports of patients who underwent surgery because of diagnosis of complicated CD. After surgery, due to persistent neutropenia, the hematologist consultant confirmed suspicions of cyclic neutropenia, and G-CSF therapy was started with benefits, underlining the crucial importance of proper differential diagnosis.

Chlorite-incorporated clay nanosheets as acid and H2O2-activated gas-bombs for combating peri-implant infection

Persistent and recurrent bacterial infections pose significant challenges during the repair and reconstruction of bone defects, necessitating the development of effective solutions to this problem. Herein, a chlorine dioxide delivery platform (LDH@Cl) comprising chlorite-incorporated clay nanosheets (MgFe layered double hydroxides, MgFe LDH) is designed and constructed. The LDH@Cl gas bomb exploits self-promoted chemical reactions in an acidic and H2O2-rich microenvironment, generating substantial amounts of ClO2 and ·OH, which exhibit potent antibacterial activity. LDH@Cl exhibits half-maximal inhibitory concentrations of 0.69 mM and 0.78 mM against Escherichia coli and Staphylococcus aureus, respectively. Furthermore, LDH@Cl exhibits good biocompatibility at a low concentration of 0.08 mM; and significant osteogenic induction effects at a high concentration of 0.8 mM, which is attributed to the release of Mg ions and Fe ions in a normal microenvironment. Furthermore, LDH@Cl promotes the expression of the osteogenic channel signaling protein BMP2, which stimulates the expression of the downstream signaling factors SMAD1, SMAD2, and SMAD3, thereby regulating the synthesis of osteogenic-related proteins. Importantly, in vivo studies demonstrate the positive therapeutic effects of LDH@Cl in bacterial eradication and accelerated osteogenesis. Thus, this novel nano “gas bomb” is promising for the clinical treatment of bacterial infection related bone defect regeneration.

Clinical features and mutational analysis of X-linked agammaglobulinemia patients in Malaysia.

Bruton's tyrosine kinase (BTK) is a cytoplasmic protein involved in the B cell development. X-linked agammaglobulinemia (XLA) is caused by mutation in the BTK gene, which results in very low or absent B cells. Affected males have markedly reduced immunoglobulin levels, which render them susceptible to recurrent and severe bacterial infections. Methods: Patients suspected with X-linked agammaglobulinemia were enrolled during the period of 2010-2018. Clinical summary, and immunological profiles of these patients were recorded. Peripheral blood samples were collected for monocyte BTK protein expression detection and BTK genetic analysis. The medical records between January 2020 and June 2023 were reviewed to investigate COVID-19 in XLA. Twenty-two patients (from 16 unrelated families) were molecularly diagnosed as XLA. Genetic testing revealed fifteen distinct mutations, including four splicing mutations, four missense mutations, three nonsense mutations, three short deletions, and one large indel mutation. These mutations scattered throughout the BTK gene and mostly affected the kinase domain. All mutations including five novel mutations were predicted to be pathogenic or deleterious by in silico prediction tools. Genetic testing confirmed that eleven mothers and seven sisters were carriers for the disease, while three mutations were de novo. Flow cytometric analysis showed that thirteen patients had minimal BTK expression (0-15%) while eight patients had reduced BTK expression (16-64%). One patient was not tested for monocyte BTK expression due to insufficient sample. Pneumonia (n=13) was the most common manifestation, while Pseudomonas aeruginosa was the most frequently isolated pathogen from the patients (n=4). Mild or asymptomatic COVID-19 was reported in four patients. This report provides the first overview of demographic, clinical, immunological and genetic data of XLA in Malaysia. The combination of flow cytometric assessment and BTK genetic analysis provides a definitive diagnosis for XLA patients, especially with atypical clinical presentation. In addition, it may also allow carrier detection and assist in genetic counselling and prenatal diagnosis.

Clinical utility of prior positive cultures to optimize empiric antibiotic therapy selection: A cross-sectional analysis

BackgroundDespite reduced infectious disease mortality and improved survival, infectious diseases continue to pose health threats due to their contagiousness, societal harm, and morbidity. Empiric antibiotic therapy, often prescribed without knowledge of the causative pathogen, faces challenges from rising antibiotic resistance. This study explores the potential of prior positive culture results to guide empiric antibiotic therapy. MethodsData from King Abdullah University Hospital (Jan 2014–Dec 2019) included adult patients with recurrent bacterial infections (pneumonia, sepsis, UTIs, wounds). Excluded cases included: mixed infections, transfers, <14 days or >12 months between episodes. The study compared bacterial growth and sensitivity patterns between previous and recent cultures. ResultsThe study included 970 episodes from 650 patients, mainly UTIs (60.3%) and gram-negative bacteria (77.9%). The study found that (65.1%) of culture pairs matched. Empirical therapy was accurate in (71.8%) of cases. Further, accuracy of selected empiric antibiotic therapy was significantly predicted (p ​< ​0.001) by: type of infection, type of antibiotics, and concordance with prior microbiologic data. Multivariate logistic analysis showed blood culture as less predictive of pending identity (OR: 0.234, P ​< ​0.001) compared to urine culture; and prior affirmed gram negative bacterial culture was less predictive (OR: 0.606, P ​= ​0.021) compared to gram positive bacterial culture. ConclusionThis study underscores the potential of prior positive culture results in guiding empiric antibiotic therapy, enhancing accuracy and identity agreement. Future research should explore this approach in different infection contexts and across multiple centers. Reducing the indiscriminate use of broad-spectrum antibiotics is essential to combat antibiotic resistance.

Good's syndrome: brief overview of an enigmatic immune deficiency.

Good's syndrome, an infrequent adult-onset immunodeficiency is characterized by the triad of thymoma, hypogammaglobulinemia, and increased susceptibility to recurrent infections. The clinical presentation is highly variable, with a spectrum ranging from recurrent bacterial and opportunistic infections to concomitant autoimmune diseases and, sometimes malignant pathologies. Due to heterogeneous clinical phenotypes and the lack of adequate diagnostic criteria, its recognition is often challenging, even delaying it by years. It is one of the most unusual, less studied form of the immune deficiency syndromes with a still unknown pathophysiology. It was initially considered a thymoma-associated variant of primary antibody deficiencies with a reduced or absent number of mature B cells, but it later emerged that significant defects of T cell-mediated immune functions are the underlying cause of opportunistic infections. On the basis of current evidence, Good's syndrome is evaluated as a distinct acquired form of combined immunodeficiency states and classified as a phenocopy of primary immunodeficiency diseases. Epigenetic and acquired genetic factors can play an ultimate role in its evolution.

Discoid lupus erythematosus associated with chronic granulomatous disease

To the Editor, Chronic granulomatous disease (CGD) is a primary immunodeficiency disorder in which a reduced activity of nicotinamide dinucleotide phosphate (NAPDH) oxidase leads to defective reactive oxygen intermediates (ROS) and impairs intracellular killing of microorganisms. Patients have recurrent bacterial and fungal infections as well as granuloma formations, and have a higher risk of autoimmune and inflammatory disorders like lupus erythematosus.1 A 20-year-old caucasian male with a diagnosis of autosomal recessive CGD was referred to our hospital because of a pruritic photosensitive rash on the face and hands, present for more than a year. [...]

Faecal Transplant Therapy: A Promising Treatment Modality for Cardiovascular Diseases

Cardiovascular diseases (CVD) are considered as “lifestyle” diseases and so far “No unified procedure” or medicines are effective in the management of this group of diseases. Researchers and clinicians have indicated that no safe therapeutic window is available in therapeutics at present. Recent research showed that gut microbiota are effective in managing lifestyle diseases therefore we introduced the influence of gut microbiota in the prognosis of the CVDs. Faecal transplant therapy(FMT) has been anticipated to treat many diseases similar to recurrent bacterial Clostridioides difficile infection which has been used worldwide. Recently, FMT was tried on an animal model to treat CVDs, and recent human trials that were tried to manage CVDs in humans by FMT showed encouraging results. The mechanism of action of transplanted bacteria to manage CVDs in the human population is also discussed. In-depth knowledge on the pros and cons of FMT will pave the way to standardize the procedure once the lacuna existing at present in treating CVDs, is paved, this technology will be useful for the masses.

Maintenance and generation of proton motive force are both essential for expression of phenotypic antibiotic tolerance in bacteria.

Bacterial antibiotic tolerance, a phenomenon first observed in 1944, is known to be responsible for both onset and exacerbation of recurrent and chronic bacterial infections. The development of antibiotic tolerance was previously thought to be due to a switch to physiological dormancy when bacteria encounter adverse growth conditions. Our recent laboratory findings, however, showed that a set of genes related to the maintenance of proton motive force (PMF) are up-regulated under starvation, indicating that the tolerant sub-population, which are commonly known as persisters, can actively maintain their tolerance phenotypes. In this study, we investigated the relative functional roles of proteins involved in the maintenance and active generation of PMF in mediating tolerance formation in bacteria and found that the PspA and RcsB proteins play a key role in PMF maintenance in persisters, as deletion of genes encoding these two proteins resulted in significantly lower tolerance levels. Consistently, expression of the OsmC and Bdm proteins, which is under regulation by RcsB, is required to maintain PMF and the antibiotic tolerance phenotypes. On the other hand, the NuoL, Ndh, AppC, CyoB, and NuoF proteins, which are electron transport chain (ETC) components, were also found to be actively expressed in persisters in order to generate PMF to support functioning of various tolerance mechanisms such as efflux activities. Our data show that active generation of PMF is even more important than the PMF maintenance functions of PspA and RcsB in the expression of antibiotic tolerance phenotypes in persisters. Assessment of double- and triple-gene knockout strains, in which the PMF maintenance genes and those encoding ETC components were simultaneously deleted, confirms that these two groups of genes are both required for the expression of antibiotic tolerance phenotypes and that a lack of these functions would result in complete PMF dissipation and accumulation of antibiotics in the intracellular compartment of persisters and eventually cell death. Products of these genes are, therefore, ideal targets for future development of anti-tolerance agents. IMPORTANCE In this work, bacteria were found to undergo active generation and maintenance of proton motive force (PMF) under adverse conditions, such as starvation so as to support a range of physiological functions in order to survive under such conditions for a prolonged period. The ability to maintain a substantial level of PMF was found to be directly linked to that exhibiting phenotypic antibiotic tolerance under nutrient starvation or other adverse conditions. These findings infer that bacteria do not simply become physiologically dormant when they become antibiotic tolerant, instead they need to produce a wide range of proteins including those which help prevent PMF dissipation, such as PspA and RcsB, and the electron transport chain components, such as NuoL and Ndh, that actively generate PMF even during long-term starvation. As antibiotic tolerant sub-population is known to play a role in eliciting recurrent and chronic infections, especially among patients with a weakened immune system, the PMF maintenance mechanisms identified in this work are potential targets for the development of new strategies to control recurrent and chronic infections.

Molecular Challenges in the Diagnosis of X-Linked Chronic Granulomatous Disease: CNVs, Intronic Variants, Skewed X-Chromosome Inactivation, and Gonosomal Mosaicism.

Chronic granulomatous disease (CGD) is a prototypical inborn error of immunity affecting phagocytes, in which these cells are unable to produce reactive oxygen species. CGD is caused by defects in genes encoding subunits of the NADPH oxidase enzyme complex (CYBA, CYBB, CYBC1, NCF1, NCF2, NCF4); inflammatory responses are dysregulated, and patients are highly susceptible to recurrent severe bacterial and fungal infections. X-linked CGD (XL-CGD), caused by mutations in the CYBB gene, is the most common and severe form of CGD. In this study, we describe the analytical processes undertaken in 3 families affected with XL-CGD to illustrate several molecular challenges in the genetic diagnosis of this condition: in family 1, a girl with a heterozygous deletion of CYBB exon 13 and skewed X-chromosome inactivation (XCI); in family 2, a boy with a hemizygous deletion of CYBB exon 7, defining its consequences at the mRNA level; and in family 3, 2 boys with the same novel intronic variant in CYBB (c.1151 + 6T > A). The variant affected the splicing process, although a small fraction of wild-type mRNA was produced. Their mother was a heterozygous carrier, while their maternal grandmother was a carrier in form of gonosomal mosaicism. In summary, using a variety of techniques, including an NGS-based targeted gene panel and deep amplicon sequencing, copy number variation calling strategies, microarray-based comparative genomic hybridization, and cDNA analysis to define splicing defects and skewed XCI, we show how to face and solve some uncommon genetic mechanisms in the diagnosis of XL-CGD.

Successful use of a phage endolysin for treatment of chronic pelvic pain syndrome/chronic bacterial prostatitis.

Chronic prostatitis (CP) is a common inflammatory condition of the prostate that is estimated to effect 2%-10% of the world's male population. It can manifest as perineal, suprapubic, or lower back pain and urinary symptoms occurring with either recurrent bacterial infection [chronic bacterial prostatitis (CBP)] or in the absence of evidence of bacterial infection [chronic pelvic pain syndrome (CPPS)]. Here, in the case of a 39 years-old CBP patient, we report the first successful use of a bacteriophage-derived muralytic enzyme (endolysin) to treat and resolve the disease. Bacteriological analysis of the patient's prostatic secretion and semen samples revealed a chronic Enterococcus faecalis prostate infection, supporting a diagnosis of CBP. The patient's E. faecalis strain was resistant to several antibiotics and developed resistance to others during the course of treatment. Previous treatment with multiple courses of antibiotics, bacteriophages, probiotics, and immunologic stimulation had failed to achieve long term eradication of the infection or lasting mitigation of the symptoms. A cloned endolysin gene, encoded by E. faecalis bacteriophage ϕEf11, was expressed, and the resulting gene product was purified to electrophoretic homogeneity. A seven-day course of treatment with the endolysin resulted in the elimination of the E. faecalis infection to below culturally detectable levels, and the abatement of symptoms to near normal levels. Furthermore, during the endolysin treatment, the patient experienced no untoward reactions. The present report demonstrates the effectiveness of an endolysin as a novel modality in managing a recalcitrant infection that could not be controlled by conventional antibiotic therapy.

E48 Thinking about auto inflammatory diseases in front of a periodicity of fever in children: a case report

Abstract Introduction Auto-inflammatory diseases (AIDs) are caused by mutations in genes involved in the regulation of innate immunity. The prototypical diseases are the hereditary recurrent fevers (HRFs), whose intermittent inflammatory manifestations are similar between the different diseases; they preferentially affect the serous membranes, skin, eyes, joints, muscles and sometimes the central nervous system. Their onset is often early in life. Objectives To think of an auto inflammatory disease in front of a periodic fever in children Method We report the case of a child with periodic fever. Results A 4-year-old boy with no particular family or personal history, who presented at the age of 1 year with episodes of high fever without evident cause lasting from 7 to 14 days, with a monthly recurrence. There was associated pharyngitis, bilateral cervical lymphadenopathy, oral aphthosis, abdominal pain, sometimes with arthralgia, vomiting, diarrhoea and skin rash. During the fever episode the inflammatory work-up is frankly positive with neutrophilic hyperleukocytosis and an elevated C-reactive protein. The duration and characteristics of the episodes are not modified by the usual antibiotic and antipyretic therapy. Viral serologies for CMV, EBV, parvovirus B19 and HIV are negative. Recurrent bacterial infections of the upper airways were ruled out in view of the periodic character, the negativity of the procalcitonin and throat swabs and the inefficiency of the antibiotic therapy during the attacks. The immune deficiency test came back normal. Autoinflammatory diseases in the absence of autoimmune signs were strongly suggested. Urinary mevalonate kinase/mevalonic acid during the episode was normal. Cyclic neutropenia was eliminated in the presence of PNN hyperleukocytosis at each episode. Genetic study of familial Mediterranean fever syndrome, cryopyrin-caps associated periodic syndrome and TRAPS syndrome came back normal. Our patient met al.l the Vanoni criteria for Marshall's syndrome. He received a single dose of prednisone 1 mg/kg which resulted in a spectacular defervescence in &amp;lt; 24 h and disappearance of other symptoms in a few days and their absence between attacks. This corticosteroid therapy was subsequently prescribed at each attack, which allowed rapid control and a reduction in the duration of the attacks. Discussion and conclusion The exact etiopathogenesis and diagnostic biomarkers of Marshall's disease are still unknown. It is rather a diagnosis of exclusion based mainly on clinical criteria. It is retained in our patient in view of the presence of all diagnostic criteria and the therapeutic test. There is no consensus on the treatment of Marshall's at present. Antipyretics can be used but are only partially effective. Single dose corticosteroids result in cessation of attacks; tonsillectomy is a secondary treatment option. Colchicine is promising for preventing or reducing the frequency of attacks. Marshall's syndrome is a self-limiting autoinflammatory disease of early childhood with spontaneous resolution without impact on the child's growth and development and without major sequelae in most cases within 3–5 years of onset.

Tazobactam/ceftolozane and tobramycin combination therapy in extensively drug-resistant Pseudomonas aeruginosa infections in severe burn injury: a case report

BackgroundCombination therapy with tazobactam/ceftolozane (TAZ/CTLZ) and high-dose aminoglycosides has been reported to be efficacious in extensively drug-resistant (XDR)-Pseudomonas aeruginosa infection. However, there are no reports of efficacy in XDR-P. aeruginosa infection for combination therapy with low-dose aminoglycosides and TAZ/CTLZ. Herein, we describe a rare case of severe burn injury patients with persistent bacteremia due to XDR-P. aeruginosa, which was successfully treated with TAZ/CTLZ and low-dose tobramycin (TOB).Case presentationA 31-year-old man was admitted to the intensive care unit with severe burn injury involving 52% of the total body surface area and a prognostic burn index of 79.5. The patient had recurrent bacterial infections since admission, and blood cultures collected on the 37th day of admission revealed the presence of P. aeruginosa strains that were resistant to all β-lactams and amikacin (AMK). The results of the antimicrobial synergistic study showed no synergistic effect of low-dose meropenem (MEPM) and AMK combination therapy. The patient had acute renal failure, and it was difficult to increase the dose of MEPM and AMK, respectively. Thus, we initiated TAZ/CTLZ 1.5 g/8 h instead of the AMK and MEPM combination therapy on the 43rd day of hospitalization. Low-dose TAZ/CTLZ was continued because of prolonged renal dysfunction and resulted in a transient clinical improvement. However, the dosage of TAZ/CTLZ could be increased as the renal function improved, but despite an increased TAZ/CTLZ dose, bacteremia persisted, and the blood cultures remained positive. Thus, TOB was added to TAZ/CTLZ at low doses for synergistic effect against Gram-negative bacteria. Blood cultures collected after initiation of combination therapy with TAZ/CTLZ and low-dose TOB were negative on two consecutive follow-up evaluations. Thereafter, although the patient had several episodes of fever and increased inflammatory response, blood cultures consistently tested negative, and all of the wounds healed. On the 93rd day, due to the good healing progress, the patient was transferred to another hospital.ConclusionsTAZ/CTLZ and low-dose TOB combination therapy showed the potential for synergistic effects. Our present report suggests a novel synergistic treatment strategy for rare cases that are refractory to the treatment of infections, such as XDR-P. aeruginosa infection.

Safety and efficacy of bronchial thermoplasty in Australia 5 years post-procedure.

Outside clinical trials, there is limited long-term data following bronchial thermoplasty (BT). In a cohort of real-world severe asthmatics in an era of biological therapy, we sought to evaluate the safety and efficacy of BT 5 years post-treatment. Every patient treated with BT at two Australian tertiary centres were recalled at 5 years, and evaluated by interview and record review, Asthma Control Questionnaire (ACQ), spirometry and high-resolution CT Chest. CT scans were interpreted using the modified Reiff and BRICS CT scoring systems for bronchiectasis. Fifty-one patients were evaluated. At baseline, this cohort had a mean age of 59.0 ± 11.8 years, mean ACQ of 3.0 ± 1.0, mean FEV1 of 55.5 ± 18.8% predicted, and 53% were receiving maintenance oral steroids in addition to triple inhaler therapy. At 5 years, there was a sustained improvement in ACQ scores to 1.8 ± 1.0 (p < 0.001). Steroid requiring exacerbation frequency was reduced from 3.8 ± 3.6 to 1.0 ± 1.6 exacerbations per annum (p < 0.001). 44% of patients had been weaned off oral steroids. No change in spirometry was observed. CT scanning identified minor degrees of localized radiological bronchiectasis in 23/47 patients with the modified Reiff score increasing from 0.6 ± 2.6 at baseline to 1.3 ± 2.5 (p < 0.001). However, no patients exhibited clinical features of bronchiectasis, such as recurrent bacterial infection. Sustained clinical benefit from BT at 5 years was demonstrated in this cohort of very severe asthmatics. Mild, localized radiological bronchiectasis was identified in a portion of patients without clinical features of bronchiectasis.

Novel mutations in CYBB Gene Cause X-linked chronic Granulomatous Disease in Pakistani patients

BackgroundChronic Granulomatous Disease (CGD) is a primary immunodeficiency that causes susceptibility to recurrent fungal and bacterial infections. The CYBB gene encodes gp91phox component of the Phagocytic Nicotinamide adenine dinucleotide phosphate (NADPH) oxidase and specifically, X-linked CGD is caused by mutations in the CYBB gene, located on the X chromosome. The aim of the study was to characterize functional and genetic mutations in X-linked CGD.MethodsFunctional analysis was conducted on the whole blood of seventeen male individuals who were suspected to have X-linked chronic granulomatous disease (CGD). Flow cytometry was employed to assess the capacity of NADPH oxidase, measuring both H2O2 production and gp91phox protein expression in neutrophils. Additionally, DNA Sanger sequencing was performed for genetic analysis. The pathogenicity of novel mutations was assessed by pathogenicity prediction tools.ResultAmong the seventeen patients evaluated, five patients (P1, P2, P3, P4, and P5) displayed impaired H2O2 production by their neutrophils upon stimulation with Phorbol myristate acetate (PMA), accompanied by abnormal gp91phox expression. DNA sequencing of the CYBB gene identified specific mutations in each patient. In P1 and P2 (previously reported cases), a hemizygous missense mutation, c.925G > A/p.E309K was identified. In P3 and P4 (novel cases), hemizygous nonsense mutations, c.216T > A/p.C72X were found. Lastly, in P5 (also a novel case), a hemizygous missense mutation, c.732T > G/p.C244W was detected. These mutations reside in exons 9,3 and 7 of the CYBB gene, respectively.ConclusionsThe current study contributes to the understanding of the clinical and genetic spectrum associated with X-linked chronic granulomatous disease (CGD). It highlights the significance of early diagnosis in CGD and emphasizes the importance of lifelong prophylaxis to prevent severe infections.

Chronic Granulomatous Disease: a Cohort of 173 Patients—10-Years Single Center Experience from Egypt

PurposeChronic granulomatous disease (CGD) is an inherited primary immunodeficiency disorder of phagocytes, characterized by recurrent fungal and bacterial infections. Our aim is to describe the different clinical presentations, non-infectious auto-inflammatory features, types and sites of infections, and to estimate the mortality among our large cohort.MethodsThis is a retrospective study conducted at the Pediatric Department of Cairo University Children’s Hospital in Egypt, including cases with a confirmed CGD diagnosis.ResultsOne hundred seventy-three confirmed CGD patients were included. AR-CGD was diagnosed in 132 patients (76.3%) including 83 patients (48%) with p47phox defect, 44 patients (25.4%) with p22phox defect, and 5 patients (2.9%) with p67phox defect. XL-CGD was diagnosed in 25 patients (14.4%). The most common recorded clinical manifestations were deep-seated abscesses and pneumonia. Gram-negative bacteria and Aspergillus were the most frequently isolated species. Regarding the outcome, 36 patients (20.8%) were lost from follow-up. Among patients with known outcome, 94/137 patients (68.6%) are living, while 43/137 patients (31.4%) died.ConclusionAR-CGD is predominant in Egypt; CGD must always be ruled out in any patient presenting with typical or atypical mycobacterial or BCG-disease.

Hematopoietic stem cell transplantation for CYBB heterozygous mutation resulting in very early onset inflammatory bowel disease in children: a case report

BackgroundInflammatory bowel disease (IBD) is a heterogeneous group of disorders associated with environmental triggers and dysregulated immune responses resulting in chronic, recurrent intestinal inflammation. Very early-onset IBD (VEO-IBD) refers to patients with symptoms or diagnosis before the age of 6 years and is widely thought to be associated with monogenic mutations. Traditional drug therapy is often ineffective in this patient population, while hematopoietic stem cell transplantation (HSCT) represents the definitive cure for patients with gene mutations.Case presentationWe report a case of VEO-IBD associated with a monogenic mutation in a 2-year-old girl presenting mainly with gastrointestinal symptoms, including recurrent hematochezia and abdominal pain for more than 3 months. A gastroscopy revealed erosive gastritis and bulbar duodenitis, while a colonoscopy indicated erosive colitis. Abnormal results were obtained from the dihydrohodamine (DHR) assay and immunoglobulin testing. Whole-exome sequencing identified a heterozygous and de novo nonsense mutation (c.388 C > T; p.R130X) in the CYBB gene leading to deficiency of nicotinamide adenine dinucleotide phosphate (NADPH) oxidase 2 (NOX2) (encoded by CYBB), a critical component of phagocytes. HSCT was performed successfully, and the DHR assay showed that normal neutrophil function was restored. Six months after HSCT, clinical remission was observed, and a repeat colonoscopy revealed intestinal mucosal healing was attained.ConclusionsPatients with CYBB mutations often develop recurrent or severe bacterial or fungal infections, mostly in the lungs, skin, lymph nodes, and liver. Here, we report on a young female child with CYBB mutations presenting predominantly with gastrointestinal symptoms. This study explores the mechanisms of inflammatory bowel disease caused by a monogenic mutation in CYBB to improve early diagnosis and effective treatment rates of this patient population.

ORCHITIS and Chronic Granulomatous Disease

Chronic Granulomatous Disease (CGD) is a primary immunodeficiency disorder, which is almost always characterized by impairment of the function of leukocytes and generally presents with recurrent chronic relapsing bacterial or fungal infection. This study reported a three-year-old boy who was referred to the Pediatric Hematology and Oncology Center of Shohada Khalij-e-Fars general hospital, Bushehr with recurrent lymphadenitis, and orchitis, who suffered from this disease. Since confirmation of diagnosis, he is receiving Co-trimoxazole three times per week as prophylaxis, and the plan for him is hematopoietic stem cell transplantation (HSCT).

Poly(sebacic acid) microparticles loaded with azithromycin as potential pulmonary drug delivery system: Physicochemical properties, antibacterial behavior, and cytocompatibility studies

Recurrent bacterial infections are a common cause of death for patients with cystic fibrosis and chronic obstructive pulmonary disease. Herein, we present the development of the degradable poly(sebacic acid) (PSA) microparticles loaded with different concentrations of azithromycin (AZ) as a potential powder formulation to deliver AZ locally to the lungs. We characterized microparticle size, morphology, zeta potential, encapsulation efficiency, interaction PSA with AZ and degradation profile in phosphate buffered saline (PBS). The antibacterial properties were evaluated using the Kirby-Bauer method against Staphylococcus aureus. Potential cytotoxicity was evaluated in BEAS-2B and A549 lung epithelial cells by the resazurin reduction assay and live/dead staining. The results show that microparticles are spherical and their size, being in the range of 1–5 μm, should be optimal for pulmonary delivery. The AZ encapsulation efficiency is nearly 100 % for all types of microparticles. The microparticles degradation rate is relatively fast – after 24 h their mass decreased by around 50 %. The antibacterial test showed that released AZ was able to successfully inhibit bacteria growth. The cytotoxicity test showed that the safe concentration of both unloaded and AZ-loaded microparticles was equal to 50 μg/ml. Thus, appropriate physicochemical properties, controlled degradation and drug release, cytocompatibility, and antibacterial behavior showed that our microparticles may be promising for the local treatment of lung infections.