Disseminated tuberculosis, CMV viraemia & haemophagocytic-lymphohistiocystosis syndrome in an adult patient with anti- IFNγ autoantibodies - case report and brief review.

We report a case of an adult female with disseminated tuberculosis, cytomegalovirus viraemia and haemophagocytic-lymphohistiocystosis syndrome associated with neutralizing anti- interferon gamma (IFNγ) autoantibodies demonstrated by absent IFNγ stimulated STAT1 phosphorylation in the presence of patient sera. A brief review of immunodeficiency caused by anti-IFNγ autoantibodies is also described.

IL-10 signaling in dendritic cells controls IL-1ß-mediated IFNγ secretion by human CD4+ T cells: relevance to inflammatory bowel disease.

Uncontrolled interferon γ (IFNγ)-mediated T-cell responses to commensal microbiota are a driver of inflammatory bowel disease (IBD). Interleukin-10 (IL-10) is crucial for controlling these T-cell responses, but the precise mechanism of inhibition remains unclear. A better understanding of how IL-10 exerts its suppressive function may allow identification of individuals with suboptimal IL-10 function among the heterogeneous population of IBD patients. Using cells from patients with an IL10RA deficiency or STAT3 mutations, we demonstrate that IL-10 signaling in monocyte-derived dendritic cells (moDCs), but not T cells, is essential for controlling IFNγ-secreting CD4+ T cells. Deficiency in IL-10 signaling dramatically increased IL-1ß release by moDCs. IL-1ß boosted IFNγ secretion by CD4+ T cells either directly or indirectly by stimulating moDCs to secrete IL-12. As predicted a signature of IL-10 dysfunction was observed in a subgroup of pediatric IBD patients having higher IL-1ß expression in activated immune cells and macroscopically affected intestinal tissue. In agreement, reduced IL10RA expression was detected in peripheral blood mononuclear cells and a subgroup of pediatric IBD patients exhibited diminished IL-10 responsiveness. Our data unveil an important mechanism by which IL-10 controls IFNγ-secreting CD4+ T cells in humans and identifies IL-1ß as a potential classifier for a subgroup of IBD patients.

ERBIN deficiency links STAT3 and TGF-ß pathway defects with atopy in humans.

Nonimmunological connective tissue phenotypes in humans are common among some congenital and acquired allergic diseases. Several of these congenital disorders have been associated with either increased TGF-ß activity or impaired STAT3 activation, suggesting that these pathways might intersect and that their disruption may contribute to atopy. In this study, we show that STAT3 negatively regulates TGF-ß signaling via ERBB2-interacting protein (ERBIN), a SMAD anchor for receptor activation and SMAD2/3 binding protein. Individuals with dominant-negative STAT3 mutations (STAT3mut ) or a loss-of-function mutation in ERBB2IP (ERBB2IPmut ) have evidence of deregulated TGF-ß signaling with increased regulatory T cells and total FOXP3 expression. These naturally occurring mutations, recapitulated in vitro, impair STAT3-ERBIN-SMAD2/3 complex formation and fail to constrain nuclear pSMAD2/3 in response to TGF-ß. In turn, cell-intrinsic deregulation of TGF-ß signaling is associated with increased functional IL-4Rα expression on naive lymphocytes and can induce expression and activation of the IL-4/IL-4Rα/GATA3 axis in vitro. These findings link increased TGF-ß pathway activation in ERBB2IPmut and STAT3mut patient lymphocytes with increased T helper type 2 cytokine expression and elevated IgE.

Therapeutic drug monitoring of posaconazole oral suspension in paediatric patients younger than 13 years of age: a retrospective analysis and literature review.

WHAT IS KNOWN AND OBJECTIVE: Posaconazole is an extended-spectrum triazole antifungal with activity against a variety of clinically significant yeasts and moulds. Posaconazole is not currently approved by the U.S. Food and Drug Administration for use in children younger than 13 years of age. Our primary objective was to describe the dosing and observed trough concentrations with posaconazole oral suspension in paediatric patients at the National Institutes of Health Clinical Center (Bethesda, MD). METHODS: This retrospective single-centre study reviewed paediatric patients younger than 13 years of age initiated on posaconazole oral suspension. Patients were included if they were initiated on posaconazole for prophylaxis or treatment for fungal infections from September 2006 through March 2013 with at least one trough concentration collected after at least 7 days of therapy. RESULTS AND DISCUSSION: A total of 20 male patients were included, of whom 15 (75%) had chronic granulomatous disease. The median age of patients was 6·5 years (range: 2·8-10·7). A total of 79 posaconazole trough concentrations were measured in patients receiving posaconazole as prophylaxis (n = 8) or treatment (n = 12). Posaconazole dose referenced to total body weight ranged from 10·0 to 49·2 mg/kg/day. Posaconazole trough concentrations ranged from undetectable (<50 ng/mL) up to 3620 ng/mL and were ≥500, ≥700 and ≥1250 ng/mL in 95%, 60% and 25% of patients, respectively. WHAT IS NEW AND CONCLUSIONS: Patients younger than 13 years of age had highly variable trough concentrations, and recommendations for the appropriate dosing of posaconazole oral suspension remain challenging. Until studies are conducted to determine the appropriate dosing of posaconazole in this patient population, therapeutic drug monitoring should be considered to ensure adequate posaconazole exposure.

Mortality among patients with pulmonary non-tuberculous mycobacteria disease.

SETTING: Tertiary referral center, National Institutes of Health (NIH), USA. OBJECTIVE: To estimate the mortality rate and its correlates among persons with pulmonary non-tuberculous mycobacteria (PNTM) disease. DESIGN: A retrospective review of 106 patients who were treated at the NIH Clinical Center and met American Thoracic Society/Infectious Diseases Society of America criteria for PNTM. Eligible patients were aged ⩾18 years and did not have cystic fibrosis or human immunodeficiency virus (HIV) infection. RESULTS: Of 106 patients followed for a median of 4.9 years, 27 (25%) died during follow-up, for a mortality rate of 4.2 per 100 person-years. The population was predominantly female (88%) and White (88%), with infrequent comorbidities. Fibrocavitary disease (adjusted hazard ratio [aHR] 3.3, 95% confidence interval [CI] 1.3-8.3) and pulmonary hypertension (aHR 2.1, 95%CI 0.9-5.1) were associated with a significantly elevated risk of mortality in survival analysis. CONCLUSIONS: PNTM remains a serious public health concern, with a consistently elevated mortality rate across multiple populations. Significant risk factors for death include fibrocavitary disease and pulmonary hypertension. Further research is needed to more specifically identify clinical and microbiologic factors that jointly influence disease outcome.

A 17-year old patient with DOCK8 deficiency, severe oral HSV-1 and aggressive periodontitis - a case of virally induced periodontitis?

We present a 17-year old girl with DOCK-8 deficiency, severe untreated oral HSV-1 infection and associated aggressive periodontitis. DOCK-8 deficiency is a primary immunodeficiency, caused by biallelicloss-of-function mutations in the DOCK8 gene, often leading to severe viral and fungal mucocutaneous infections. Nevertheless, to date DOCK8 has not been associated with severe periodontitis and inflammatory bone loss around teeth. Understanding whether DOCK8 deficiency or severe HSV-1 infection underlies susceptibility to periodontitis is central to this case and may provide insights into susceptibility factors for periodontitis in the general population. Our clinical and microbiological data suggest that severe HSV-1 infection is the driver of periodontal inflammation in this case.

Activated STING in a vascular and pulmonary syndrome.

BACKGROUND: The study of autoinflammatory diseases has uncovered mechanisms underlying cytokine dysregulation and inflammation. METHODS: We analyzed the DNA of an index patient with early-onset systemic inflammation, cutaneous vasculopathy, and pulmonary inflammation. We sequenced a candidate gene, TMEM173, encoding the stimulator of interferon genes (STING), in this patient and in five unrelated children with similar clinical phenotypes. Four children were evaluated clinically and immunologically. With the STING ligand cyclic guanosine monophosphate-adenosine monophosphate (cGAMP), we stimulated peripheral-blood mononuclear cells and fibroblasts from patients and controls, as well as commercially obtained endothelial cells, and then assayed transcription of IFNB1, the gene encoding interferon-ß, in the stimulated cells. We analyzed IFNB1 reporter levels in HEK293T cells cotransfected with mutant or nonmutant STING constructs. Mutant STING leads to increased phosphorylation of signal transducer and activator of transcription 1 (STAT1), so we tested the effect of Janus kinase (JAK) inhibitors on STAT1 phosphorylation in lymphocytes from the affected children and controls. RESULTS: We identified three mutations in exon 5 of TMEM173 in the six patients. Elevated transcription of IFNB1 and other gene targets of STING in peripheral-blood mononuclear cells from the patients indicated constitutive activation of the pathway that cannot be further up-regulated with stimulation. On stimulation with cGAMP, fibroblasts from the patients showed increased transcription of IFNB1 but not of the genes encoding interleukin-1 (IL1), interleukin-6 (IL6), or tumor necrosis factor (TNF). HEK293T cells transfected with mutant constructs show elevated IFNB1 reporter levels. STING is expressed in endothelial cells, and exposure of these cells to cGAMP resulted in endothelial activation and apoptosis. Constitutive up-regulation of phosphorylated STAT1 in patients' lymphocytes was reduced by JAK inhibitors. CONCLUSIONS: STING-associated vasculopathy with onset in infancy (SAVI) is an autoinflammatory disease caused by gain-of-function mutations in TMEM173. (Funded by the Intramural Research Program of the National Institute of Arthritis and Musculoskeletal and Skin Diseases; ClinicalTrials.gov number, NCT00059748.).

Impaired cytokine responses in patients with cryopyrin-associated periodic syndrome (CAPS).

Cryopyrin-associated periodic syndrome (CAPS) is characterized by dysregulated inflammation with excessive interleukin (IL)-1ß activation and secretion. Neonatal-onset multi-system inflammatory disease (NOMID) is the most severe form. We explored cytokine responses in 32 CAPS patients before and after IL-1ß blocking therapy. We measured cytokines produced by activated peripheral blood monuclear cells (PBMCs) from treated and untreated CAPS patients after stimulation for 48 h with phytohaemagglutinin (PHA), PHA plus IL-12, lipopolysaccharide (LPS) or LPS plus interferon (IFN)-γ. We measured IL-1ß, IL-6, IL-10, tumour necrosis factor (TNF), IL-12p70 and IFN-γ in the supernatants. PBMCs from three untreated CAPS patients were cultured in the presence of the IL-1ß blocker Anakinra. Fifty healthy individuals served as controls. CAPS patients had high spontaneous production of IL-1ß, IL-6, TNF and IFN-γ by unstimulated cells. However, stimulation indexes (SIs, ratio of stimulated to unstimulated production) of these cytokines to PHA and LPS were low in NOMID patients compared to controls. Unstimulated IL-10 and IL-12p70 production was normal, but up-regulation after PHA and LPS was also low. LPS plus IFN-γ inadequately up-regulated the production of IL-1ß, IL-6, TNF and IL-10 in CAPS patients. In-vitro but not in-vivo treatment with Anakinra improved SIs by lowering spontaneous cytokine production. However, in-vitro treatment did not improve the low stimulated cytokine levels. Activating mutations in NLRP3 in CAPS are correlated with poor SIs to PHA, LPS and IFN-γ. The impairment in stimulated cytokine responses in spite of IL-1ß blocking therapy suggests a broader intrinsic defect in CAPS patients, which is not corrected by targeting IL-1ß.

Generalized verrucosis in a patient with GATA2 deficiency.

Generalized verrucosis is a characteristic of several genetic and immunodeficiency disorders including epidermodysplasia verruciformis; warts, hypogammaglobulinaemia, infections and myelokathexis (WHIM) syndrome; warts, immunodeficiency, lymphoedema and anogenital dysplasia (WILD) syndrome; severe combined immune deficiency and HIV, among others. In recent years, it has been consistently recognized in patients with GATA2 deficiency, a novel immunodeficiency syndrome characterized by monocytopenia, B-cell and natural killer-cell lymphopenia, and a tendency to develop myeloid leukaemias and disseminated mycobacterial, human papillomavirus (HPV) and opportunistic fungal infections. Mutations in GATA2 cause haploinsufficiency and track in families as an autosomal dominant immunodeficiency. GATA2 is a transcription factor involved in early haematopoietic differentiation and lymphatic and vascular development. We describe a case of generalized verrucosis with HPV type 57 presenting in a young man with GATA2 deficiency. GATA2 deficiency is a novel dominant immunodeficiency that is often recognized later in life and should be considered in the differential diagnosis of patients with generalized verrucosis.

Interferon alpha treatment of patients with impaired interferon gamma signaling.

Patients with deficiency in the interferon gamma receptor (IFN-γR) are unable to respond properly to IFN-γ and develop severe infections with nontuberculous mycobacteria (NTM). IFN-γ and IFN-α are known to signal through STAT1 and activate many downstream effector genes in common. Therefore, we added IFN-α for treatment of patients with disseminated mycobacterial disease in an effort to complement their IFN-γ signaling defect. We treated four patients with IFN-γR deficiency with adjunctive IFN-α therapy in addition to best available antimicrobial therapy, with or without IFN-γ, depending on the defect. During IFN-α treatment, ex vivo induction of IFN target genes was detected. In addition, IFN-α driven gene expression in patients' cells and mycobacteria induced cytokine response were observed in vitro. Clinical responses varied in these patients. IFN-α therapy was associated with either improvement or stabilization of disease. In no case was disease exacerbated. In patients with profoundly impaired IFN-γ signaling who have refractory infections, IFN-α may have adjunctive anti-mycobacterial effects.

Pulmonary non-tuberculous mycobacterial infection in congenital contractural arachnodactyly.

Congenital contractural arachnodactyly (CCA) is caused by mutations within the fibrillin-2 gene (FBN2), which is crucial for microfibril structure. Affected individuals may have contractures, chest wall deformities, scoliosis, abnormal ear folding and elongated limbs. We describe a novel FBN2 mutation in a woman with CCA who also had pulmonary non-tuberculous mycobacteria (NTM) infection. The population with pulmonary NTM infections shares phenotypic features with CCA, such as elongated body habitus, scoliosis and pectus deformities. While it is unlikely that FBN2 defects account for susceptibility to NTM infection in the majority of cases, the overlap between these two diseases suggests some shared pathophysiology.

New mechanism of oral immunity to mucosal candidiasis in hyper-IgE syndrome.

Oropharyngeal candidiasis (OPC, thrush) is an opportunistic infection caused by the commensal fungus Candida albicans. An understanding of immunity to Candida has recently begun to unfold with the identification of fungal pattern-recognition receptors such as C-type lectin receptors, which trigger protective T-helper (Th)17 responses in the mucosa. Hyper-IgE syndrome (HIES/Job's syndrome) is a rare congenital immunodeficiency characterized by dominant-negative mutations in signal transducer and activator of transcription 3, which is downstream of the Th17-inductive cytokines interleukin (IL)-6 and IL-23, and hence patients with HIES exhibit dramatic Th17 deficits. HIES patients develop oral and mucocutaneous candidiasis, supporting a protective role for Th17 cells in immunity to OPC. However, the Th17-dependent mechanisms of antifungal immunity in OPC are still poorly defined. An often unappreciated aspect of oral immunity is saliva, which is rich in antimicrobial proteins (AMPs) and exerts direct antifungal activity. In this study, we show that HIES patients show significant impairment in salivary AMPs, including ß-defensin 2 and Histatins. This tightly correlates with reduced candidacidal activity of saliva and concomitantly elevated colonization with Candida. Moreover, IL-17 induces histatins in cultured salivary gland cells. This is the first demonstration that HIES is associated with defective salivary activity, and provides a mechanism for the severe susceptibility of these patients to OPC.

The relationship between alloimmunization and posttransfusion granulocyte survival: experience in a chronic granulomatous disease cohort.

BACKGROUND: The efficacy of granulocyte transfusions in patients with HLA alloimmunization is uncertain. A flow cytometric assay using dihydrorhodamine 123 (DHR), a marker for cellular NADPH oxidase activity, was used to monitor the differential survival of transfused oxidase-positive granulocytes in alloimmunized patients with chronic granulomatous disease (CGD). STUDY DESIGN AND METHODS: Ten patients with CGD and serious infections were treated with daily granulocyte transfusions derived from steroid and granulocyte-colony-stimulating factor-stimulated donors. The proportion of neutrophils with intact oxidase activity was quantitated by DHR fluorescence on samples drawn before and 1 hour after transfusion. The incidence of acute transfusion reactions was correlated with the results of DHR fluorescence and biweekly HLA serologic screening assays. RESULTS: Eight of 10 patients experienced acute adverse reactions in association with granulocyte transfusions. Four had only chills and/or fever, and four experienced respiratory compromise; all eight exhibited HLA alloimmunization. Mean (± SD) oxidase-positive cell recovery was 19.7 ± 17.4% (n = 15 transfusions) versus 0.95 ± 1.59% (n = 16) in the absence and presence of HLA allosensitization, respectively (p < 0.01). Greater than 1% in vivo recovery of DHR-enhancing donor granulocytes was strongly correlated with lack of HLA alloimmunization. CONCLUSION: The ability to detect DHR-positive donor granulocytes by flow cytometry is strongly correlated with absence of HLA alloimmunization and lack of acute reactions to granulocyte transfusions in patients with CGD. If HLA antibodies are present and the survival of donor granulocytes is low by DHR analysis, transfusions should be discontinued, avoiding a therapy associated with high risk and unclear benefit.

Neosartorya udagawae (Aspergillus udagawae), an emerging agent of aspergillosis: how different is it from Aspergillus fumigatus?

A recent report on several cases of invasive aspergillosis caused by Neosartorya udagawae suggested distinctive patterns of disease progression between N. udagawae and Aspergillus fumigatus. This prompted us to characterize N. udagawae in comparison to A. fumigatus. Our findings showed that both species exist in two mating types at similar ratios and produce gliotoxin. However, the thermotolerance of the two species differs: while A. fumigatus is able to grow at 55 degrees C but not at 10 degrees C, N. udagawae is able to grow at 10 degrees C but fails to grow at >42 degrees C. Furthermore, compared to A. fumigatus, the conidia of N. udagawae require longer incubation periods to germinate at 37 degrees C and are more susceptible to neutrophil attack as well as hydrogen peroxide; N. udagawae is also less virulent in gp91(phox-/-) mice. These findings suggest that growth and susceptibility to the host response might account for the reduced virulence of N. udagawae and the subtle distinction in the progression of the disease caused by the two species.

Hyper IgE (Job's) syndrome: a primary immune deficiency with oral manifestations.

Autosomal dominant hyper IgE (HIES or Job's) syndrome is a rare primary immune deficiency characterized by eczema, recurrent skin and lung infections, extremely elevated serum IgE, and a variety of connective tissue and skeletal abnormalities. Individuals with HIES share a characteristic facial appearance and many oral manifestations including retained primary dentition, a high arched palate, variations of the oral mucosa and gingiva, and recurrent oral candidiasis. Mutations in STAT3 account for the majority, if not all, of the cases of autosomal dominant HIES, but the pathogenesis of the many varied features remains poorly understood. In this review, we discuss the clinical phenotype of HIES including immunologic and non-immunologic features, the genetics of HIES, and treatment.