Immunological Effects of Anti‒IL-17/12/23 Therapy in Patients with Psoriasis Complicated by Candida Infections.

Biologics that block the T helper (Th) 17 pathway are very effective in the treatment of psoriasis and other inflammatory diseases. However, IL-17 is also crucial for antifungal host defense, and clinical trial data suggest an increase in the incidence of Candida infections during IL-17 inhibitor (IL-17i) therapy. We investigated the innate and adaptive immune responses of patients with psoriasis with a history of skin and/or mucosal candidiasis during IL-17i or IL-12/23 inhibitor therapy, comparing those responses with those of healthy controls. Patients with psoriasis with IL-17i showed significantly lower CD4+Th1-like (CCR6‒CXCR3+CCR4‒) and Th1 Th17-like (CD4+CCR6+CXCR3+CCR4‒) cell percentages. Patient cells stimulated with Candida albicans produced significantly lower IL-6 in the IL-12/23 inhibitor group and IL-1ß in the IL-17i group, whereas the release of TNF-α and ROS was similar between patients and controls. IFN-γ and IL-10 production in response to several stimuli after 7 days was particularly decreased in patients receiving IL-17i therapy. Finally, after stimulation with the polarizing cytokines IL-1ß and IL-23, the Th17 cytokine response was significantly lower in the IL-17i patient group. These innate and adaptive immune response defects can diminish antifungal host immune response and thereby increase susceptibility to candidiasis in patients treated with IL-17i or IL-12/23 inhibitor.

Global Risk of Bacterial Skin Infections and Herpesviridae Infections with Ustekinumab, Secukinumab, and Tumour Necrosis Factor-alpha Inhibitors: Spontaneous Reports of Adverse Drug Reactions from the World Health Organization Pharmacovigilance Center.

Genetic defects in interleukin-12/23/17 immunity are associated with an increased risk of Staphylococcus aureus and herpesvirus skin infections. This study analysed spontaneous safety reports from the WHO Pharmacovigilance Center of bacterial skin or herpesvirus infections associated with secukinumab, ustekinumab and tumour necrosis factor-α inhibitors. Associations found in disproportionality analyses were expressed as reporting odds ratios (ROR). For bacterial skin infections, ustekinumab showed the strongest association (ROR 6.09; 95% confidence interval (95% CI) 5.44-6.81), and, among the tumour necrosis factor-α inhibitors, infliximab showed the strongest association (ROR 4.18; 95% CI 3.97-4.40). Risk was comparable between infliximab and secukinumab (ROR 3.51; 95% CI 3.00-4.09). Secukinumab showed the strongest association with herpes simplex infection (ROR 4.80; 95% CI 3.78-6.10). All biologics were equally associated with herpes zoster. Infliximab was the only biologic associated with cytomegalovirus infection (ROR 5.66; 95% CI 5.08-6.31) and had the strongest association with Epstein-Barr virus infection (ROR 6.90; 95% CI 6.03-7.90). All biologics evaluated were positively associated with bacterial skin infections, herpes simplex, and herpes zoster, compared with all other drugs in the WHO database for which individual case safety reports were collected. The possibility of under-reporting, reporting bias and difference in causality assessment between countries and reporters must be taken into account when interpreting the results of disproportionality analyses.

An Exaggerated Monocyte-Derived Cytokine Response to Candida Hyphae in Patients With Recurrent Vulvovaginal Candidiasis.

BACKGROUND: Recurrent vulvovaginal candidiasis (RVVC) affects up to 8% of women. The immunopathogenesis is poorly understood but it has been suggested that RVVC might be due to dysregulated innate immune response. The aim of this study was to compare cytokine profiles in stimulated primary mononuclear cells (PBMCs) from RVVC and healthy individuals. METHODS: PBMCs isolated from RVVC patients (n = 24) and healthy volunteers (n = 30) were stimulated with unspecific and pathogen-specific antigens. Cytokine production was assessed after 24 hours, 48 hours, and 7 days using ELISA. RESULTS: No significant differences in cytokine production were found in T helper 1 (Th1), Th2, and Th17 immunity in response to both unspecific and pathogen-specific stimulations. Tumor necrosis factor-α (TNF-α) production in response to C. albicans hyphae was significantly higher in patients than controls and within the patient group, a significant positive correlation was found between interleukin-1ß (IL-1ß) and both TNF-α and IL-6. Both IL-1ß/IL-1Ra and TNF-α/IL-10 ratios in Candida hyphae-stimulated PBMCs were significantly higher in patients than controls. CONCLUSIONS: Women affected by RVVC showed increased monocytes-derived cytokine production, which might contribute to an exaggerated vaginal immune response to Candida hyphae. RVVC patients show no defective Th-dependent adaptive immune response upon Candida stimulation.

EORTC/MSGERC Definitions of Invasive Fungal Diseases: Summary of Activities of the Intensive Care Unit Working Group.

The EORTC/MSGERC recently revised and updated the consensus definitions of invasive fungal disease (IFD). These definitions primarily focus on patients with cancer and stem cell or solid-organ transplant patients. They may therefore not be suitable for intensive care unit (ICU) patients. More in detail, while the definition of proven IFD applies to a broad range of hosts, the categories of probable and possible IFD were primarily designed for classical immunocompromised hosts and may therefore not be ideal for other populations. Moreover, the scope of the possible category of IFD has been diminished in the recently revised definitions for classically immunocompromised hosts. Diagnosis of IFD in the ICU presents many challenges, which are different for invasive candidiasis and for invasive aspergillosis. The aim of this article is to review progresses made in recent years and difficulties remaining in the development of definitions applicable in the ICU setting.

Revision and Update of the Consensus Definitions of Invasive Fungal Disease From the European Organization for Research and Treatment of Cancer and the Mycoses Study Group Education and Research Consortium.

BACKGROUND: Invasive fungal diseases (IFDs) remain important causes of morbidity and mortality. The consensus definitions of the Infectious Diseases Group of the European Organization for Research and Treatment of Cancer and the Mycoses Study Group have been of immense value to researchers who conduct clinical trials of antifungals, assess diagnostic tests, and undertake epidemiologic studies. However, their utility has not extended beyond patients with cancer or recipients of stem cell or solid organ transplants. With newer diagnostic techniques available, it was clear that an update of these definitions was essential. METHODS: To achieve this, 10 working groups looked closely at imaging, laboratory diagnosis, and special populations at risk of IFD. A final version of the manuscript was agreed upon after the groups' findings were presented at a scientific symposium and after a 3-month period for public comment. There were several rounds of discussion before a final version of the manuscript was approved. RESULTS: There is no change in the classifications of "proven," "probable," and "possible" IFD, although the definition of "probable" has been expanded and the scope of the category "possible" has been diminished. The category of proven IFD can apply to any patient, regardless of whether the patient is immunocompromised. The probable and possible categories are proposed for immunocompromised patients only, except for endemic mycoses. CONCLUSIONS: These updated definitions of IFDs should prove applicable in clinical, diagnostic, and epidemiologic research of a broader range of patients at high-risk.

A Genome-Wide Functional Genomics Approach Identifies Susceptibility Pathways to Fungal Bloodstream Infection in Humans.

BACKGROUND: Candidemia, one of the most common causes of fungal bloodstream infection, leads to mortality rates up to 40% in affected patients. Understanding genetic mechanisms for differential susceptibility to candidemia may aid in designing host-directed therapies. METHODS: We performed the first genome-wide association study on candidemia, and we integrated these data with variants that affect cytokines in different cellular systems stimulated with Candida albicans. RESULTS: We observed strong association between candidemia and a variant, rs8028958, that significantly affects the expression levels of PLA2G4B in blood. We found that up to 35% of the susceptibility loci affect in vitro cytokine production in response to Candida. Furthermore, potential causal genes located within these loci are enriched for lipid and arachidonic acid metabolism. Using an independent cohort, we also showed that the numbers of risk alleles at these loci are negatively correlated with reactive oxygen species and interleukin-6 levels in response to Candida. Finally, there was a significant correlation between susceptibility and allelic scores based on 16 independent candidemia-associated single-nucleotide polymorphisms that affect monocyte-derived cytokines, but not with T cell-derived cytokines. CONCLUSIONS: Our results prioritize the disturbed lipid homeostasis and oxidative stress as potential mechanisms that affect monocyte-derived cytokines to influence susceptibility to candidemia.

Prophylactic antibiotics reduce hospitalisations and cost in locally advanced head and neck cancer patients treated with chemoradiotherapy: A randomised phase 2 study.

BACKGROUND: Platinum-based chemoradiotherapy for locally advanced head and neck cancer (LAHNC) induces a high rate of acute toxicity, including dysphagia and aspiration pneumonia. We hypothesised that prophylactic antibiotics can prevent pneumonia and hospitalisations and can be cost-effective. PATIENT AND METHODS: In this multicentre randomised trial, patients with LAHNC treated with chemoradiotherapy received prophylactic amoxicillin/clavulanic acid from day 29 after the start of treatment until 14 days after completion of chemoradiotherapy or standard care without prophylaxis. The primary objective was to observe a reduction in pneumonias. Secondary objectives were to evaluate the hospitalisation rate, adverse events, costs and health-related quality of life. RESULTS: One hundred six patients were included; of which, 95 were randomised: 48 patients were allocated to the standard group and 47 patients to the prophylaxis group. A pneumonia during chemoradiotherapy and follow-up until 3.5 months was observed in 22 (45.8%) of 48 patients in the standard group and in 22 (46.8%) of 47 patients in the prophylaxis group (p = 0.54). Hospitalisation rate was significantly higher in the standard group versus the prophylaxis group, 19 of 48 pts (39.6%) versus 9 of 47 pts (19.1%), respectively (p = 0.03). Significantly more episodes with fever of any grade were observed in the standard group (29.2% vs 10.2%, p = 0.028). A significant difference in costs was found, with an average reduction of €1425 per patient in favour of the prophylaxis group. CONCLUSION: Although prophylactic antibiotics during chemoradiotherapy for patients with LAHNC did not reduce the incidence of pneumonias, it did reduce hospitalisation rates and episodes with fever significantly and consequently tended to be cost-effective.

18F-FDG PET/CT-Guided Treatment Duration in Patients with High-Risk Staphylococcus Aureus Bacteremia: A Proof of Principle.

Current guidelines recommend intravenous antibiotic therapy for at least 4 wk in patients with high-risk Staphylococcus aureus bacteremia (SAB), because of the risk for metastatic infection. We evaluated the safety of a shorter duration of treatment in patients with high-risk SAB without signs of metastatic infection at presentation, using standard 18F-FDG PET/CT and echocardiography. Methods: Retrospective analyses were performed of patients with SAB admitted between 2013 and 2017 in 2 medical centers. Patients with risk factors for complicated bacteremia (community acquisition, persistently positive blood cultures, >72 h of fever, or foreign body materials present), a normal echocardiography result, and 18F-FDG PET/CT without signs of metastatic infection were included (cases) and compared with patients with uncomplicated bacteremia (absence of any of the risk factors and no known metastatic disease, controls). Primary outcomes were 3-mo SAB-specific mortality rate and recurrent infection. The secondary outcome was overall mortality. Results: We included 36 cases and 40 controls. Both groups had a similar treatment duration (15.9 vs. 15.4 d). No deaths occurred as a consequence of SAB in the cases, compared with 1 in the control group. One relapse occurred in the case group and 2 in the control group. Overall mortality did not differ between the groups (19.4% vs. 15.0%, P = 0.64). Conclusion: This study suggests that intravenous treatment for 2 wk in high-risk patients with SAB without endocarditis and absence of metastatic infection on 18F-FDG PET/CT is safe. A diagnostic-driven approach using 18F-FDG PET/CT to determine treatment duration in high-risk SAB seems feasible and allows tailoring treatment to individual patients.

Clinical Outcome of Antibiotic Suppressive Therapy in Patients with a Prosthetic Joint Infection after Hip Replacement.

Introduction: In Specific cases, curative treatment of a prosthetic joint infection (PJI) cannot be accomplished due to the increased risk of major complications after prosthetic joint revision surgery. In these patients, antibiotic suppressive therapy (AST) is often used to control the infection. Aim: To describe the clinical outcome of patients with a PJI after hip replacement treated with AST. Methods: Patients in which AST for PJI was started between 2006 and 2013, were retrospectively included. Follow-up was continued until October 2018. AST has been defined as treatment with oral antibiotic therapy intended to suppress PJI. Treatment was considered successful in patients without reoperation for PJI or death related to PJI during follow-up. Results: Twenty-three patients were included. The most commonly used antibiotics were doxycycline (n=14) and cotrimoxazole (n=6). The mean duration of AST was 38 months (1-151 months). AST was considered successful in 13 patients (56.5%) after a median follow-up of 33 months. AST was least successful in PJI caused by S. aureus with 80% failures versus 33% in PJI caused by other microorganisms and in patients who had an antibiotic-free period before the start of AST with 83% failures. Two patients ended AST due to side effects. Conclusion: AST can be an alternative treatment in selected patients with a PJI after hip replacement. However, there is a persisting and considerable amount of failures, particularly in PJI caused by S. aureus and in patient with an antibiotic-free period before the start of AST.

Invasive candidiasis.

Invasive candidiasis is an important health-care-associated fungal infection that can be caused by several Candida spp.; the most common species is Candida albicans, but the prevalence of these organisms varies considerably depending on geographical location. The spectrum of disease of invasive candidiasis ranges from minimally symptomatic candidaemia to fulminant sepsis with an associated mortality exceeding 70%. Candida spp. are common commensal organisms in the skin and gut microbiota, and disruptions in the cutaneous and gastrointestinal barriers (for example, owing to gastrointestinal perforation) promote invasive disease. A deeper understanding of specific Candida spp. virulence factors, host immune response and host susceptibility at the genetic level has led to key insights into the development of early intervention strategies and vaccine candidates. The early diagnosis of invasive candidiasis is challenging but key to the effective management, and the development of rapid molecular diagnostics could improve the ability to intervene rapidly and potentially reduce mortality. First-line drugs, including echinocandins and azoles, are effective, but the emergence of antifungal resistance, especially among Candida glabrata, is a matter of concern and underscores the need to administer antifungal medications in a judicious manner, avoiding overuse when possible. A newly described pathogen, Candida auris, is an emerging multidrug-resistant organism that poses a global threat.

Neutrophils differentially attenuate immune response to Aspergillus infection through complement receptor 3 and induction of myeloperoxidase.

Invasive aspergillosis (IA) remains a major cause of morbidity in immunocompromised hosts. This is due to the inability of the host immunity to respond appropriately to Aspergillus. An established risk factor for IA is neutropenia that is encountered by patients undergoing chemotherapy. Herein, we investigate the role of neutrophils in modulating host response to Aspergillus. We found that neutrophils had the propensity to suppress proinflammatory cytokine production but through different mechanisms for specific cytokines. Cellular contact was requisite for the modulation of interleukin-1 beta production by Aspergillus with the involvement of complement receptor 3. On the other hand, inhibition of tumour necrosis factor-alpha production (TNF-α) was cell contact-independent and mediated by secreted myeloperoxidase. Specifically, the inhibition of TNF-α by myeloperoxidase was through the TLR4 pathway and involved interference with the mRNA transcription of TNF receptor-associated factor 6/interferon regulatory factor 5. Our study illustrates the extended immune modulatory role of neutrophils beyond its primary phagocytic function. The absence of neutrophils and loss of its inhibitory effect on cytokine production explains the hypercytokinemia seen in neutropenic patients when infected with Aspergillus.

18F-FDG PET/CT Optimizes Treatment in Staphylococcus Aureus Bacteremia and Is Associated with Reduced Mortality.

Metastatic infection is an important complication of Staphylococcus aureus bacteremia (SAB). Early diagnosis of metastatic infection is crucial, because specific treatment is required. However, metastatic infection can be asymptomatic and difficult to detect. In this study, we investigated the role of 18F-FDG PET/CT in patients with SAB for detection of metastatic infection and its consequences for treatment and outcome. Methods: All patients with SAB at Radboud University Medical Center were included between January 2013 and April 2016. Clinical data and results of 18F-FDG PET/CT and other imaging techniques, including echocardiography, were collected. Primary outcomes were newly diagnosed metastatic infection by 18F-FDG PET/CT, subsequent treatment modifications, and patient outcome. Results: A total of 184 patients were included, and 18F-FDG PET/CT was performed in 105 patients, of whom 99 had a high-risk bacteremia. 18F-FDG PET/CT detected metastatic infectious foci in 73.7% of these high-risk patients. In 71.2% of patients with metastatic infection, no signs and symptoms suggesting metastatic complications were present before 18F-FDG PET/CT was performed. 18F-FDG PET/CT led to a total of 104 treatment modifications in 74 patients. Three-month mortality was higher in high-risk bacteremia patients without 18F-FDG PET/CT performed than in those in whom 18F-FDG PET/CT was performed (32.7% vs. 12.4%, P = 0.003). In multivariate analysis, 18F-FDG PET/CT was the only factor independently associated with reduced mortality (P = 0.005; odds ratio, 0.204; 95% confidence interval, 0.066-0.624). A higher comorbidity score was independently associated with increased mortality (P = 0.003; odds ratio, 1.254; 95% confidence interval, 1.078-1.457). Conclusion:18F-FDG PET/CT is a valuable technique for early detection of metastatic infectious foci, often leading to treatment modification. Performing 18F-FDG PET/CT is associated with significantly reduced 3-mo mortality.

Functional and Genomic Architecture of Borrelia burgdorferi-Induced Cytokine Responses in Humans.

Despite the importance of immune variation for the symptoms and outcome of Lyme disease, the factors influencing cytokine production during infection with the causal pathogen Borrelia burgdorferi remain poorly understood. Borrelia infection-induced monocyte- and T cell-derived cytokines were profiled in peripheral blood from two healthy human cohorts of Western Europeans from the Human Functional Genomics Project. Both non-genetic and genetic host factors were found to influence Borrelia-induced cytokine responses. Age strongly impaired IL-22 responses, and genetic studies identified several independent QTLs that impact Borrelia-induced cytokine production. Genetic, transcriptomic, and functional validation studies revealed an important role for HIF-1α-mediated glycolysis in the cytokine response to Borrelia. HIF-1α pathway activation and increase in glycolysis-derived lactate was confirmed in Lyme disease patients. In conclusion, functional genomics approaches reveal the architecture of cytokine production induced by Borrelia infection of human primary leukocytes and suggest a connection between cellular glucose metabolism and Borrelia-induced cytokine production.

International expert opinion on the management of infection caused by azole-resistant Aspergillus fumigatus.

An international expert panel was convened to deliberate the management of azole-resistant aspergillosis. In culture-positive cases, in vitro susceptibility testing should always be performed if antifungal therapy is intended. Different patterns of resistance are seen, with multi-azole and pan-azole resistance more common than resistance to a single triazole. In confirmed invasive pulmonary aspergillosis due to an azole-resistant Aspergillus, the experts recommended a switch from voriconazole to liposomal amphotericin B (L-AmB; Ambisome(®)). In regions with environmental resistance rates of ≥10%, a voriconazole-echinocandin combination or L-AmB were favoured as initial therapy. All experts recommended L-AmB as core therapy for central nervous system aspergillosis suspected to be due to an azole-resistant Aspergillus, and considered the addition of a second agent with the majority favouring flucytosine. Intravenous therapy with either micafungin or L-AmB given as either intermittent or continuous therapy was recommended for chronic pulmonary aspergillosis due to a pan-azole-resistant Aspergillus. Local and national surveillance with identification of clinical and environmental resistance patterns, rapid diagnostics, better quality clinical outcome data, and a greater understanding of the factors driving or minimising environmental resistance are areas where research is urgently needed, as well as the development of new oral agents outside the azole drug class.

Th17 cytokine deficiency in patients with Aspergillus skull base osteomyelitis.

BACKGROUND: Fungal skull base osteomyelitis (SBO) is a severe complication of otitis externa or sinonasal infection, and is mainly caused by Aspergillus species. Here we investigate innate and adaptive immune responses in patients with Aspergillus SBO to identify defects in the immune response that could explain the susceptibility to this devastating disease. METHODS: Peripheral blood mononuclear cells isolated from six patients with Aspergillus SBO and healthy volunteers were stimulated with various microbial stimuli, among which also the fungal pathogens Candida albicans and Aspergillus fumigatus. The proinflammatory cytokines IL-6, TNFα and IL-1ß, and the T-helper cell-derived cytokines IFNγ, IL-17 and IL-22 were measured in cell culture supernatants by ELISA. RESULTS: Proinflammatory cytokine responses did not differ between SBO patients and healthy volunteers. The Candida- and Aspergillus-specific Th17 response (production of IL-17 and IL-22) was significantly decreased in the SBO patients compared to healthy individuals, while Th1 cytokine response (IFNγ production) did not differ between the two groups. CONCLUSIONS: We show that patients with Aspergillus skull base osteomyelitis infection have specific defects in Th17 responses. Since IL-17 and IL-22 are important for stimulating antifungal host defense, we hypothesize that strategies that have the ability to improve IL-17 and IL-22 production may be useful as adjuvant immunotherapy in patients with Aspergillus SBO.

The RIG-I-like helicase receptor MDA5 (IFIH1) is involved in the host defense against Candida infections.

The induction of host defense against Candida species is initiated by recognition of the fungi by pattern recognition receptors and activation of downstream pathways that produce inflammatory mediators essential for infection clearance. In this study, we present complementary evidence based on transcriptome analysis, genetics, and immunological studies in knockout mice and humans that the cytosolic RIG-I-like receptor MDA5 (IFIH1) has an important role in the host defense against C. albicans. Firstly, IFIH1 expression in macrophages is specifically induced by invasive C. albicans hyphae, and patients suffering from chronic mucocutaneous candidiasis (CMC) express lower levels of MDA5 than healthy controls. Secondly, there is a strong association between missense variants in the IFIH1 gene (rs1990760 and rs3747517) and susceptibility to systemic Candida infections. Thirdly, cells from Mda5 knockout mice and human peripheral blood mononuclear cells (PBMCs) with different IFIH1 genotypes display an altered cytokine response to C. albicans. These data strongly suggest that MDA5 is involved in immune responses to Candida infection. As a receptor for viral RNA, MDA5 until now has been linked to antiviral host defense, but these novel studies show unexpected effects in antifungal immunity as well. Future studies are warranted to explore the potential of MDA5 as a novel target for immunotherapeutic strategies.

Human TLR10 is an anti-inflammatory pattern-recognition receptor.

Toll-like receptor (TLR)10 is the only pattern-recognition receptor without known ligand specificity and biological function. We demonstrate that TLR10 is a modulatory receptor with mainly inhibitory effects. Blocking TLR10 by antagonistic antibodies enhanced proinflammatory cytokine production, including IL-1ß, specifically after exposure to TLR2 ligands. Blocking TLR10 after stimulation of peripheral blood mononuclear cells with pam3CSK4 (Pam3Cys) led to production of 2,065 ± 106 pg/mL IL-1ß (mean ± SEM) in comparison with 1,043 ± 51 pg/mL IL-1ß after addition of nonspecific IgG antibodies. Several mechanisms mediate the modulatory effects of TLR10: on the one hand, cotransfection in human cell lines showed that TLR10 acts as an inhibitory receptor when forming heterodimers with TLR2; on the other hand, cross-linking experiments showed specific induction of the anti-inflammatory cytokine IL-1 receptor antagonist (IL-1Ra, 16 ± 1.7 ng/mL, mean ± SEM). After cross-linking anti-TLR10 antibody, no production of IL-1ß and other proinflammatory cytokines could be found. Furthermore, individuals bearing TLR10 polymorphisms displayed an increased capacity to produce IL-1ß, TNF-α, and IL-6 upon ligation of TLR2, in a gene-dose-dependent manner. The modulatory effects of TLR10 are complex, involving at least several mechanisms: there is competition for ligands or for the formation of heterodimer receptors with TLR2, as well as PI3K/Akt-mediated induction of the anti-inflammatory cytokine IL-1Ra. Finally, transgenic mice expressing human TLR10 produced fewer cytokines when challenged with a TLR2 agonist. In conclusion, to our knowledge we demonstrate for the first time that TLR10 is a modulatory pattern-recognition receptor with mainly inhibitory properties.

Antibiotic mixing through impacted bone grafts does not seem indicated in two-stage cemented hip revisions for septic loosening.

Impaction bone grafts (IBG) in two-stage revision for prosthetic hip infection (PHI) might be more susceptible for infection, therefore antibiotic mixing through these grafts has been suggested. However, outcomes have not been compared with IBG without antibiotics and no long-term results are available. Therefore, we evaluated long-term infection-free outcome after the use of IBG without antibiotic supplement in two-stage revision for PHI. Patients were divided into positive (group 1, n = 8) and negative (group 2, n = 28) cultures at re-implantation and followed up to 18 years after re-implantation. Five of 36 patients died from non-orthopaedic causes (median 37, range 24-149 months). Five patients had a re-operation not related to infection (median 39, range 7-140 months). These were censored in the Kaplan-Meier estimator at the last outpatient evaluation. We found an overall re-infection rate of 2.8% within two years, which matches comparative studies in which antibiotic impregnated bone grafts had been used. In group 1, there was one re-infection after 44 months. In group 2, all three infections occurred within 56 months with an estimated infection-free percentage at 10 years of 87% (95% CI 66-96). Follow-up should be extended beyond two years and randomised clinical trials are needed for further comparison with IBG impregnated with antibiotics.

Cytokine production assays reveal discriminatory immune defects in adults with recurrent infections and noninfectious inflammation.

Cytokine production assays have been primarily used in research settings studying novel immunodeficiencies. We sought to determine the diagnostic value of cytokine production assays in patients with recurrent and/or severe infectious diseases (IDs) without known immunodeficiencies and unclassified noninfectious inflammatory disorders (NIIDs). We retrospectively examined cytokine production in whole-blood and peripheral blood mononuclear cell samples from 157 adult patients. A cytokine production rate of <5% of that of healthy controls was considered defective. While monocyte-derived cytokine (tumor necrosis factor alpha [TNF-α], interleukin-1ß [IL-1ß], and IL-6) production was rarely affected, 30% of all included patients had deficient production of interferon gamma (IFN-γ), IL-17A, or IL-22. Twenty-five percent of the NIID patients displayed defective IFN-γ production, whereas IL-17A production was generally unaffected. In the group of ID patients, defective IFN-γ production was found in 19% and 14% of the patients with viral and bacterial infections, respectively, and in 38%, 24%, and 50% of patients with mycobacterial, mucocutaneous, and invasive fungal infections, respectively. Defective IL-17A and IL-22 production was mainly confined to ID patients with mucocutaneous fungal infections. In conclusion, cytokine production assays frequently detect defective Th1 responses in patients with mycobacterial or fungal infections, in contrast to patients with respiratory tract infections or isolated bacterial infections. Defective IL-17A and IL-22 production was primarily found in patients with fungal infections, while monocyte-derived cytokine production was unaffected. Thus, lymphocyte-derived cytokine production assays are helpful in the diagnostic workup of patients with recurrent infections and suspected immunodeficiencies and have the potential to reveal immune defects that might guide adjunctive immunomodulatory therapy.

Role of autophagy genetic variants for the risk of Candida infections.

Candida albicans can cause candidemia in neutropenic and critically ill patients and oropharyngeal candidiasis in human immunodeficiency virus (HIV)-positive patients with low CD4(+) counts. Because all patients at risk do not develop Candida infections, it is possible that a patient's genetic background might play a role in his or her susceptibility to infection. Autophagy mediates pathogen clearance and modulation of inflammation. Our aim was to assess the effect of genetic variations in the ATG16L1 and IRGM autophagy genes on the susceptibility of patients with candidemia and oropharyngeal candidiasis. We assessed genetic variations in the ATG16L1 and IRGM genes in a cohort of candidemia patients of both African and European origin. In addition, we evaluated the effect of these polymorphisms on the susceptibility to oropharyngeal candidiasis of an HIV-positive cohort from Tanzania. Functional studies have been performed to assess the effect of the ATG16L1 and IRGM genetic variants on both in vitro and in vivo cytokine production. The results indicate that ATG16L1 variants modulate production of tumor necrosis factor-alpha, but not other cytokines, while no effects were seen in the presence of IRGM polymorphisms. In addition, no significant associations between the single-nucleotide polymorphisms in the ATG16L1 and IRGM genetic variants and the incidence of candidemia or oropharyngeal candidiasis were identified. Despite moderate effects on the modulation of proinflammatory cytokine production, genetic variation in the autophagy genes ATG16L1 and IRGM has a minor impact on the susceptibility to both mucosal and systemic Candida infections.