Burden of disease and risk factors for death among children treated for tuberculosis in Malawi

SETTING

Tuberculosis (TB) is a leading cause of childhood death. Patient-level data on pediatric TB in Malawi that can be used to guide programmatic interventions are limited.

OBJECTIVE

To describe pediatric TB case burden, disease patterns, treatment outcomes, and risk factors for death and poor outcome.

DESIGN

We conducted a retrospective cohort study utilizing routine data. Odds ratios (ORs) for factors associated with poor outcome and death were calculated using generalized estimating equations.

RESULTS

Children represented 8% (371/4642) of TB diagnoses. The median age was 7 years (interquartile range 2.8-11); 32.8% (113/345) were human immunodeficiency virus (HIV) infected. Of these, 54.0% were on antiretroviral therapy (ART) at the time of anti-tuberculosis treatment (ATT) initiation, 21.2% started ART during ATT, and 24.8% had no documented ART. The treatment success rate was 77.3% (11.2% cured, 66.1% completed treatment), with 22.7% experiencing poor outcomes (9.5% died, 13.2% were lost to follow-up). Being on ART at the time of ATT initiation was associated with increased odds of death compared to beginning ART during treatment (adjusted OR 2.75, 95%CI 1.27-5.96).

CONCLUSION

Children represent a small proportion of diagnosed TB cases and experience poor outcomes. Higher odds of death among children already on ART raises concerns over the management of these children. Further discussion of and research into pediatric-specific strategies is required to improve case finding and outcomes.

Increased circulating endocan in patients with cirrhosis: relation to bacterial infection and severity of disease

Life expectancy of patients with liver cirrhosis is closely linked to the degree of liver dysfunction and the occurrence of bacterial infection. An early diagnosis of infection helps to initiate adequate and timely measures and improves outcome of cirrhotic patients. Endocan is a newly recognized biomarker of sepsis. However, there have been no studies of the trends in endocan levels in cirrhotic patients with bacterial infection and their associations with markers of infection and inflammation. This study sought to assess the diagnostic value of serum levels of endocan, procalcitonin (PCT), C-reactive protein (CRP), tumor necrosis factor-α (TNF-α), and interleukin-6 (IL-6) in 126 patients with cirrhosis: 51 with decompensated infected cirrhosis, 56 with decompensated uninfected and 19 with compensated uninfected cirrhosis at inclusion. We analyzed the association of endocan with clinical factors in cirrhosis by comparison with indicators of infection and inflammation. Endocan, PCT, CRP, IL-6 and TNF-α were assayed in serum samples by ELISA analyses. Serum levels of endocan, PCT, CRP and TNF-α were significantly higher in cirrhotic patients with clinically overt infections. Endocan levels were correlated to neither PCT levels nor IL-6 levels in each group of patients with cirrhosis. CRP and TNF-α levels and Child-Pugh score correlated only in the infected group of patients with endocan levels, while in the uninfected groups of cirrhotic patients no significant correlation could be detected. The diagnostic accuracy of endocan increased in advanced stage of the disease. Serum endocan levels ≥ 2.05 ng/ml had a sensitivity of 76.1% and specificity of 85% for the diagnosis bacterial infection in decompensated cirrhotic patients. The endocan measured at admission is a good clinical parameter predicting the occurrence of infection in these patients. Elevated endocan may reflect the degree of endothelial cell injury induced by a systemic inflammatory response, a pathologic process that could modify the course of advanced cirrhosis.

The Orphan Receptor GPR17 Is Unresponsive to Uracil Nucleotides and Cysteinyl Leukotrienes

Pairing orphan G protein–coupled receptors (GPCRs) with their cognate endogenous ligands is expected to have a major impact on our understanding of GPCR biology. It follows that the reproducibility of orphan receptor ligand pairs should be of fundamental importance to guide meaningful investigations into the pharmacology and function of individual receptors. GPR17 is an orphan receptor characterized by some as a dualistic uracil nucleotide/cysteinyl leukotriene receptor and by others as inactive toward these stimuli altogether. Whereas regulation of central nervous system myelination by GPR17 is well established, verification of activity of its putative endogenous ligands has proven elusive so far. Herein we report that uracil nucleotides and cysteinyl leukotrienes do not activate human, mouse, or rat GPR17 in various cellular backgrounds, including primary cells, using eight distinct functional assay platforms based on labelfree pathway-unbiased biosensor technologies, as well as canonical second-messenger or biochemical assays. Appraisal of GPR17 activity can neither be accomplished with co-application of both ligand classes, nor with exogenous transfection of partner receptors (nucleotide P2Y12, cysteinyl-leukotriene CysLT1) to reconstitute the elusive pharmacology. Moreover, our study does not support the inhibition of GPR17 by the marketed antiplatelet drugs cangrelor and ticagrelor, previously suggested to antagonize GPR17. Whereas our data do not disagree with a role of GPR17 per se as an orchestrator of central nervous system functions, they challenge the utility of the proposed (ant)agonists as tools to imply direct contribution of GPR17 in complex biologic settings.

FZD10-Gα13 signalling axis points to a role of FZD10 in CNS angiogenesis

Among the 10 Frizzled (FZD) isoforms belonging to the Class F of G protein-coupled receptors (GPCRs), FZD₁₀ remains the most enigmatic. FZD₁₀ shows homology to FZD₄ and FZD₉ and was previously implicated in both β-catenin-dependent and -independent signalling. In normal tissue, FZD₁₀ levels are generally very low; however, its upregulation in synovial carcinoma has attracted some attention for therapy. Our findings identify FZD₁₀ as a receptor interacting with and signalling through the heterotrimeric G protein Gα₁₃ but not Gα_12, Gα_i1, Gα_oA, Gα_s, or Gα_q. Stimulation with the FZD agonist WNT induced the dissociation of the Gα₁₃ protein from FZD₁₀, and led to global Gα_12/13-dependent cell changes assessed by dynamic mass redistribution measurements. Furthermore, we show that FZD₁₀ mediates Gα_12/13 activation-dependent induction of YAP/TAZ transcriptional activity. In addition, we show a distinct expression of FZD₁₀ in embryonic CNS endothelial cells at E11.5-E14.5. Given the well-known importance of Gα₁₃ signalling for the development of the vascular system, the selective expression of FZD₁₀ in brain vascular endothelial cells points at a potential role of FZD₁₀-Gα₁₃ signalling in CNS angiogenesis.

Real-world effectiveness and safety of ombitasvir/paritaprevir/ritonavir ± dasabuvir ± ribavirin in hepatitis C: AMBER study

BACKGROUND

Virologic and safety outcomes of ombitasvir/paritaprevir/ritonavir ± dasabuvir ± ribavirin (OBV/PTV/r ± DSV ± RBV) therapy have shown high sustained virologic response (SVR) rates and good tolerability in most patient populations in pre-registration studies.

AIM

To confirm these clinical trial findings in the treatment of genotype 1 and 4 hepatitis C under real-world conditions.

METHODS

Patients enrolled for treatment with OBV/PTV/r ± DSV ± RBV based on therapeutic guidelines were included, and the regimen was administered according to product characteristics. Clinical and laboratory data, including virologic response, were collected at baseline, end of treatment (EOT) and 12 weeks after EOT.

RESULTS

A total of 209 patients with chronic hepatitis C were enrolled, most were genotype 1b-infected (84.2%) and 119 (56.9%) had liver cirrhosis. Among these, 150 (71.7%) had failed previous anti-viral therapies and 84 (40.2%) were null-responders. At 12 weeks after EOT, SVR was achieved by 207 (99.0%) patients, ranging from 96.4% to 100.0% across subgroups. All Child-Pugh B and post-orthotopic liver transplantation patients achieved SVR. Adverse events occurred in 151 (72.2%) patients and were mostly mild and associated with the use of RBV. Serious adverse events, including hepatic decompensation, renal insufficiency, anaemia, hepatotoxicity and diarrhoea, were reported in eight (3.8%) patients. In five (2.4%) patients, adverse events led to treatment discontinuation. On-treatment decompensation was experienced by seven (3.3%) patients.

CONCLUSIONS

The results of our study confirm previous findings. They demonstrate excellent effectiveness and a good safety profile of OBV/PTV/r± DSV±RBV in HCV genotype 1-infected patients treated in the real-world setting.

Peginterferon add-on results in more HBsAg decline compared to monotherapy in HBeAg-positive chronic hepatitis B patients

It is unknown whether peginterferon (PEG-IFN) add-on to entecavir (ETV) leads to more HBsAg decline compared to PEG-IFN monotherapy or combination therapy, and whether ETV therapy may prevent HBsAg increase after PEG-IFN cessation. We performed a post hoc analysis of 396 HBeAg-positive patients treated for 72 weeks with ETV + 24 weeks PEG-IFN add-on from week 24 to 48 (add-on, n = 85), 72 weeks with ETV monotherapy (n = 90), 52 weeks with PEG-IFN monotherapy (n = 111) and 52 weeks PEG-IFN + lamivudine (combination, n = 110) within 2 randomized trials. HBsAg decline was assessed at the end of PEG-IFN (EOP) and 6 months after PEG-IFN (EOF) discontinuation. Differences in baseline characteristics were accounted for using inversed probability of treatment weights. At EOP, a HBsAg reduction of ≥1log10 IU/mL was more frequently achieved for patients in the add-on or combination therapy arms (both 36%), compared to PEG-IFN mono (20%) or ETV (8%) (add-on vs PEG-IFN mono P = 0.050). At EOF, the HBsAg reduction ≥1log10 IU/mL was only sustained in patients treated with ETV consolidation (add-on vs combination and PEG-IFN mono: 40% vs 23% and 18%, P = 0.029 and P = 0.003, respectively). For add-on, combination, PEG-IFN mono and ETV, the mean HBsAg-level change at EOF was -0.84, -0.81, -0.68 and -0.33 log10 IU/mL, respectively (P > 0.05 for PEG-IFN arms). HBeAg loss at EOF was 36%, 31%, 33% and 20%, respectively (P > 0.05). PEG-IFN add-on for 24 weeks results in more on-treatment HBsAg decline than does 52 weeks of PEG-IFN monotherapy. ETV therapy may maintain the HBsAg reduction achieved with PEG-IFN.

Effects of early life dextran sulfate sodium administration on pathology and immune response in broilers and layers

Intestinal pathology early in life may affect immune development and therefore immune responses later in life. Dextran sulfate sodium (DSS) induces colitis in rodents and is a widely used model for inflammatory bowel diseases. The present study investigated DSS as a model for early life intestinal pathology and its consequences on intestinal pathology, ileal cytokine, and immunoglobulin mRNA expression levels as well as the antibody response towards an immunological challenge later in life in chickens. Broiler and layer chicks received 2.5% DSS in drinking water during d 11 through d 18 post hatch or plain drinking water as a control. As an immunological challenge all birds received a combination of Escherichia coli lipopolysaccharide (LPS) and human serum albumin (HuSA) intramuscularly (i.m.) at d 35, and antibody titers against LPS, HuSA, and keyhole limpet hemocyanin (KLH) were determined to investigate effects of intestinal inflammation early in life on humoral immunity later in life. DSS treated birds showed a decrease in BW from which broilers quickly recovered, but which persisted for several weeks in layers. Histological examination of intestinal samples showed symptoms similar to those in rodents, including shortening and loss of villi and crypts as well as damage of the epithelial cell layer of different parts of the intestine. Effects of DSS on intestinal morphology were less severe in broilers that also showed a lower mortality in response to DSS than layers. No effect of DSS on ileal cytokine expression levels could be observed, but ileal immunoglobulin expression levels were decreased in DSS treated broilers that also showed lower antibody titers against LPS in response to the challenge. In conclusion, DSS may serve as a model for intestinal pathology early in life, although more research on the appropriate dose is necessary and is likely to differ between breeds. Results from the present study could indicate that broilers are less susceptible to DSS compared with layers or have a better capacity to recover from intestinal pathology.

Long-term effects of early life microbiota disturbance on adaptive immunity in laying hens

Due to an interplay between intestinal microbiota and immune system, disruption of intestinal microbiota composition during immune development may have consequences for immune responses later in life. The present study investigated the effects of antibiotic treatment in the first weeks of life on the specific antibody response later in life in chickens. Layer chicks received an antibiotic cocktail consisting of vancomycin, neomycin, metronidazole, and amphotericin-B by oral gavage every 12 h, and ampicillin and colistin in drinking water for the first week of life. After the first week of life, chicks received ampicillin and colistin in drinking water for two more weeks. Control birds received no antibiotic cocktail and plain drinking water. Fecal microbiota composition was determined during antibiotic treatment (d 8 and 22), two weeks after cessation of antibiotic treatment (d 36), and at the end of the experimental period at d 175 using a 16S ribosomal RNA gene targeted microarray, the Chicken Intestinal Tract Chip (ChickChip). During antibiotic treatment fecal microbiota composition differed strongly between treatment groups. Fecal microbiota of antibiotic treated birds consisted mainly of Proteobacteria, and in particular E.coli, whereas fecal microbiota of control birds consisted mainly of Firmicutes, such as lactobacilli and clostridia. Two weeks after cessation of antibiotic treatment fecal microbiota composition of antibiotic treated birds had recovered and was similar to that of control birds. On d 105, 12 weeks after cessation of antibiotic treatment, chicks of both treatment groups received an intra-tracheal lipopolysaccharide (LPS)/human serum albumin (HuSA) challenge. Antibody titers against LPS and HuSA were measured 10 days after administration of the challenge. While T cell independent antibody titers (LPS) were not affected by antibiotic treatment, antibiotic treated birds showed lower T cell dependent antibody titers (HuSA) compared with control birds. In conclusion, intestinal microbial dysbiosis early in life may still have effects on the specific antibody response months after cessation of antibiotic treatment and despite an apparent recovery in microbiota composition.

The Orphan G Protein-coupled Receptor GPR17 Negatively Regulates Oligodendrocyte Differentiation via Gαi/o and Its Downstream Effector Molecules

Recent studies have recognized G protein-coupled receptors as important regulators of oligodendrocyte development. GPR17, in particular, is an orphan G protein-coupled receptor that has been identified as oligodendroglial maturation inhibitor because its stimulation arrests primary mouse oligodendrocytes at a less differentiated stage. However, the intracellular signaling effectors transducing its activation remain poorly understood. Here, we use Oli-neu cells, an immortalized cell line derived from primary murine oligodendrocytes, and primary rat oligodendrocyte cultures as model systems to identify molecular targets that link cell surface GPR17 to oligodendrocyte maturation blockade. We demonstrate that stimulation of GPR17 by the small molecule agonist MDL29,951 (2-carboxy-4,6-dichloro-1H-indole-3-propionic acid) decreases myelin basic protein expression levels mainly by triggering the Gαi/o signaling pathway, which in turn leads to reduced activity of the downstream cascade adenylyl cyclase-cAMP-PKA-cAMP response element-binding protein (CREB). In addition, we show that GPR17 activation also diminishes myelin basic protein abundance by lessening stimulation of the exchange protein directly activated by cAMP (EPAC), thus uncovering a previously unrecognized role for EPAC to regulate oligodendrocyte differentiation. Together, our data establish PKA and EPAC as key downstream effectors of GPR17 that inhibit oligodendrocyte maturation. We envisage that treatments augmenting PKA and/or EPAC activity represent a beneficial approach for therapeutic enhancement of remyelination in those demyelinating diseases where GPR17 is highly expressed, such as multiple sclerosis.

Loss of intrahepatic HBsAg expression predicts sustained response to peginterferon and is reflected by pronounced serum HBsAg decline

There is a lack of knowledge regarding the effect of peginterferon (PEG-IFN) on the expression of intrahepatic hepatitis B core and surface antigen (HBcAg and HBsAg) in chronic hepatitis B (CHB) and its relation with response to therapy. Fifty-two HBeAg-positive and 67 HBeAg-negative CHB patients with paired liver biopsies taken at baseline and after 1 year of PEG-IFN therapy were studied. After PEG-IFN therapy, HBeAg-negative patients showed a significant reduction in both intrahepatic HBcAg (P = 0.04) and HBsAg expression (P < 0.001). In contrast, a reduction in intrahepatic HBcAg expression was not observed in HBeAg-positive patients, while a trend in reduction of intrahepatic HBsAg staining was found (P = 0.09). Post-treatment, 7 (13%) HBeAg-positive and 9 (14%) HBeAg-negative patients had no expression of intrahepatic HBsAg. Patients without any intrahepatic HBsAg expression post-treatment were more likely to achieve a combined response (HBeAg loss with hepatitis B virus (HBV) DNA <2000 IU/mL for HBeAg -positive and HBV DNA <2000 IU/mL and normal alanine aminotransferase for HBeAg-negative CHB): 71% vs 5% for HBeAg-positive (P < 0.001) and 60% vs 16% for HBeAg-negative patients (P = 0.004), respectively. Moreover, a more profound decline of serum HBsAg was observed in patients with absence of intrahepatic HBsAg staining (3.1 vs 0.4 log IU/mL, P < 0.001 and 1.7 vs 0.4 log IU/mL, P = 0.005 for HBeAg-positive and HBeAg-negative CHB, respectively). In conclusion, PEG-IFN reduces expression of intrahepatic HBsAg. Loss of HBsAg as assessed by immunohistochemistry from the liver predicts a sustained response and is reflected in a pronounced serum HBsAg decline.

Development of ileal cytokine and immunoglobulin expression levels in response to early feeding in broilers and layers

Provision of feed in the immediate posthatch period may influence interaction between intestinal microbiota and immune system, and consequently immunological development of the chick. This study addressed ileal immune development in response to early feeding in 2 chicken breeds selected for different production traits: broilers and layers. Chicks of both breeds either received feed and water immediately posthatch or were subjected to a 72-h feed and water delay. Ileal cytokine and immunoglobulin mRNA expression levels were determined at different time points. Effects of early feeding were limited, but breeds differed strikingly regarding cytokine and immunoglobulin expression levels. Cytokine expression levels in broilers were low compared with layers and showed a transient drop in the second to third week of life. In contrast, broilers showed considerably higher expression levels of IgA, IgM, and IgY. These findings indicate that the 2 breeds use different immune strategies, at least on the ileal level.

Polymorphisms of HLA-DP are associated with response to peginterferon in Caucasian patients with chronic hepatitis B

BACKGROUND

Polymorphisms of the HLA-DP gene are associated with the natural clearance of the hepatitis B virus in Asian patients.

AIM

To investigate the association of HLA-DP polymorphisms with response to peginterferon (PEG-IFN) in Caucasian chronic hepatitis B (CHB) patients.

METHODS

We studied 262 Caucasian chronic hepatitis B patients infected with HBV genotype A or D, treated with PEG-IFN for 1 year in two randomised controlled trials (HBV 99-01 and PARC study). Response was defined as an HBV DNA <2000 IU/mL at 6 months post-treatment. Variations at HLA-DPA1 and HLA-DPB1 were genotyped.

RESULTS

Of the 262 patients, 58% was HBeAg-positive and HBV genotype A and D was observed in 32% and 68%, respectively. At 6 months post-treatment, 57 (22%) patients had achieved an HBV DNA <2000 IU/mL. HLA-DPB1 was independently associated with virological response [adjusted odds ratio (OR) 1.8, 95% confidence interval (CI):1.1-3.0, P = 0.025], and with an undetectable HBV DNA (adjusted OR 2.4 95% CI: 1.2-4.7, P = 0.015) when adjusted for HBeAg status and other known response modifiers. In HBeAg-positive patients, combined HBeAg seroconversion with HBV DNA <2000 IU/mL was increasingly observed with each addition of an HLA-DPB1 G-allele (adjusted OR 2.7, 95% CI: 1.2-5.9, P = 0.012). Furthermore, HLA-DPA1 and HLA-DPB1 haplotype block GG showed comparable results for virological and combined response.

CONCLUSION

In this large cohort of Caucasian chronic hepatitis B patients infected with HBV genotypes A or D, polymorphisms of HLA-DP are independently associated with both virological and serological response to PEG-IFN therapy at 6 months post-treatment.

[Use of negative pressure wound therapy on surgical incisions (prevena™) after surgery of pectus deformities reduces wound complications]

INTRODUCTION

Pectus surgery can lead to postoperative wound complications in some cases. The purpose of this study is to determine whether preventive negative pressure wound therapy (NPWT) could reduce wound complications after open pectus surgery.

MATERIAL AND METHODS

100 patients after open procedure for the treatment of pectus excavatum or pectus carinatum in the years 2010 to 2012 were retrospectively analysed. 50 patients treated with Prevena™ (KCI Medical Products GmbH, Wiesbaden, Germany) were compared with 50 patients whose wounds were covered with OPSITE® film (Smith & Nephew, Hamburg, Germany). Wound closure was performed following a standard procedure as well as the placement of subcutaneous drains. Therefore two comparable groups of patients were formed and analysed by standardised parameters. The wound dressing was placed epicutaneously immediately after wound closure in the operating room and removed after 5 days in each case. Follow-ups were performed immediately after removal of the wound dressing, at the time of discharge from hospital as well as 6 and 12 weeks after operation. The wounds were checked for tenderness, pain, secretion, redness and fistulas.

RESULTS

The Prevena group showed 10 % wound complications which needed operative treatment, whereas the OPSITE group showed complications in 24 %. Some patients who were treated with Prevena showed superficial skin lesions at the rim of the foam and the film. All of these lesions healed well.

CONCLUSION

Treating wounds postoperatively with preventive measures (NPWT) showed a remarkable reduction of wound complications following open pectus surgery whereas statistically the difference was not significant (p = 0.074).

Predictors associated with treatment initiation and switch in a real-world chronic hepatitis B population from five European countries

In Europe, healthcare systems differ between countries and different factors may influence Chronic hepatitis B (CHB) treatment choices in different counties. This analysis from a prospective, longitudinal, non-interventional study in five EU countries aimed to explore determinants associated with treatment initiation or switch in patients with CHB. A total of 1267 adult patients with compensated CHB in Germany, France, Poland, Romania and Turkey were prospectively followed for up to 2 years (March 2008-December 2010). Determinants of treatment initiation or switch were analysed using multivariate Cox proportional hazards regression. Median time since CHB diagnosis was 2.6 (0-37.7) years. Among 646 treatment-naïve patients, the probability of treatment initiation during follow-up was higher: in Germany (P = 0.0006), Poland (P < 0.0001) and Romania (P = 0.0004) compared with Turkey; in patients with alanine transaminase (ALT) 1-2 × upper limit of normal (ULN) (P = 0.0580) or >2 × ULN (P = 0.0523) compared with ALT ≤ 1 × ULN; and in patients with hepatitis B virus (HBV) DNA ≥ 2000 IU/mL (P < 0.0001) compared with HBV DNA <2000 IU/mL or undetectable. Among 567 treated patients, 87 switched treatment during follow-up. The probability of treatment switch was higher: in France (P = 0.0029), Germany (P = 0.0078) and Poland (P = 0.0329) compared with Turkey; and in patients with HBV DNA <2000 (P < 0.0001) or ≥ 2000 IU/mL (P < 0.0001), compared with undetectable. Viral load and ALT level were identified as the major drivers of treatment initiation. HBV DNA level was also a significant determinant of treatment switch. Results were statistically different across EU countries.

Decoding signaling and function of the orphan G protein-coupled receptor GPR17 with a small-molecule agonist

Replacement of the lost myelin sheath is a therapeutic goal for treating demyelinating diseases of the central nervous system (CNS), such as multiple sclerosis (MS). The G protein (heterotrimeric guanine nucleotide-binding protein)-coupled receptor (GPCR) GPR17, which is phylogenetically closely related to receptors of the "purinergic cluster," has emerged as a modulator of CNS myelination. However, whether GPR17-mediated signaling positively or negatively regulates this critical process is unresolved. We identified a small-molecule agonist, MDL29,951, that selectively activated GPR17 even in a complex environment of endogenous purinergic receptors in primary oligodendrocytes. MDL29,951-stimulated GPR17 engaged the entire set of intracellular adaptor proteins for GPCRs: G proteins of the Gα(i), Gα(s), and Gα(q) subfamily, as well as β-arrestins. This was visualized as alterations in the concentrations of cyclic adenosine monophosphate and inositol phosphate, increased Ca²⁺ flux, phosphorylation of extracellular signal-regulated kinases 1 and 2 (ERK1/2), as well as multifeatured cell activation recorded with label-free dynamic mass redistribution and impedance biosensors. MDL29,951 inhibited the maturation of primary oligodendrocytes from heterozygous but not GPR17 knockout mice in culture, as well as in cerebellar slices from 4-day-old wild-type mice. Because GPCRs are attractive targets for therapeutic intervention, inhibiting GPR17 emerges as therapeutic strategy to relieve the oligodendrocyte maturation block and promote myelin repair in MS.