Comparing Effectiveness of a Generic Oral Nutritional Supplement With Specialized Formula in the Treatment of Active Pediatric Crohn's Disease

BACKGROUND

Exclusive enteral nutrition (EEN) is the recommended induction treatment of mild to moderate active pediatric Crohn's disease (CD). This study compared outcomes of 2 proprietary polymeric formulas. Treatment effectiveness was examined along with practical aspects of formula delivery and differences in estimated treatment costs.

METHODS

Data were retrospectively collected from patients with CD who received a generic oral nutritional supplement (Fortisip) across 2 centers (RCH, Melbourne and RHSC, Edinburgh). This was compared with a prospective cohort (RHC, Glasgow) that used a specialized formula (Modulen IBD). The data collected included patient demographics, remission rates, biochemical markers, administration method, and anthropometrics. The estimated treatment cost was performed by comparing price per kcal between each formula.

RESULTS

One hundred seventy-one patients were included (106 Fortisip, 65 Modulen IBD, 70 female; median age 13.3 yrs). No difference was demonstrated in remission rate (Fortisip n = 67 of 106 [63%] vs Modulen IBD n = 41 of 64 [64%], P = .89), nonadherence rate (Fortisip n = 7 of 106 [7%] vs Modulen IBD 3 of 64 [5%], P = .57) or method of administration (NGT Fortisip use n = 16 of 106 [12%] vs Modulen IBD 14 of 65 [22%]; P = .31). There was no difference in reduction of biochemical disease markers between the groups (C-reactive protein , P = .13; erythrocyte sedimentation rate, P = .49; fecal calprotectin, P = .94). However, there was a cost-saving of around £500/patient/course if the generic oral nutritional supplement was used.

CONCLUSIONS

The generic oral nutritional supplement and specialized formulas both had similar clinical effectiveness in induction of remission in pediatric CD. However, there is considerable cost-saving when using a generic oral nutritional supplement.

Toll-like Receptor 9 Promotes Initiation of Gastric Tumorigenesis by Augmenting Inflammation and Cellular Proliferation

BACKGROUND & AIMS

Gastric cancer (GC) is strongly linked with chronic gastritis after Helicobacter pylori infection. Toll-like receptors (TLRs) are key innate immune pathogenic sensors that mediate chronic inflammatory and oncogenic responses. Here, we investigated the role of TLR9 in the pathogenesis of GC, including Helicobacter infection.

METHODS

TLR9 gene expression was profiled in gastric tissues from GC and gastritis patients and from the spontaneous gp130^F/F GC mouse model and chronic H felis-infected wild-type (WT) mice. Gastric pathology was compared in gp130^F/F and H felis infection models with or without genetic ablation of Tlr9. The impact of Tlr9 targeting on signaling cascades implicated in inflammation and tumorigenesis (eg, nuclear factor kappa B, extracellular signal-related kinase, and mitogen-activated protein kinase) was assessed in vivo. A direct growth-potentiating effect of TLR9 ligand stimulation on human GC cell lines and gp130^F/F primary gastric epithelial cells was also evaluated.

RESULTS

TLR9 expression was up-regulated in Helicobacter-infected gastric tissues from GC and gastritis patients and gp130^F/F and H felis-infected WT mice. Tlr9 ablation suppressed initiation of tumorigenesis in gp130^F/F:Tlr9^-/- mice by abrogating gastric inflammation and cellular proliferation. Tlr9^-/- mice were also protected against H felis-induced gastric inflammation and hyperplasia. The suppressed gastric pathology upon Tlr9 ablation in both mouse models associated with attenuated nuclear factor kappa B and, to a lesser extent, extracellular signal-related kinase, mitogen-activated protein kinase signaling. TLR9 ligand stimulation of human GC cells and gp130^F/F GECs augmented their proliferation and viability.

CONCLUSIONS

Our data reveal that TLR9 promotes the initiating stages of GC and facilitates Helicobacter-induced gastric inflammation and hyperplasia, thus providing in vivo evidence for TLR9 as a candidate therapeutic target in GC.

The Nestin neural enhancer is essential for normal levels of endogenous Nestin in neuroprogenitors but is not required for embryo development

Enhancers are vitally important during embryonic development to control the spatial and temporal expression of genes. Recently, large scale genome projects have identified a vast number of putative developmental regulatory elements. However, the proportion of these that have been functionally assessed is relatively low. While enhancers have traditionally been studied using reporter assays, this approach does not characterise their contribution to endogenous gene expression. We have studied the murine Nestin (Nes) intron 2 enhancer, which is widely used to direct exogenous gene expression within neural progenitor cells in cultured cells and in vivo. We generated CRISPR deletions of the enhancer region in mice and assessed their impact on Nes expression during embryonic development. Loss of the Nes neural enhancer significantly reduced Nes expression in the developing CNS by as much as 82%. By assessing NES protein localization, we also show that this enhancer region contains repressor element(s) that inhibit Nes expression within the vasculature. Previous reports have stated that Nes is an essential gene, and its loss causes embryonic lethality. We also generated 2 independent Nes null lines and show that both develop without any obvious phenotypic effects. Finally, through crossing of null and enhancer deletion mice we provide evidence of trans-chromosomal interaction of the Nes enhancer and promoter.

A partially randomised trial of pretomanid, moxifloxacin and pyrazinamide for pulmonary TB

BACKGROUND: Treatment for TB is lengthy and toxic, and new regimens are needed.METHODS: Participants with pulmonary drug-susceptible TB (DS-TB) were randomised to receive: 200 mg pretomanid (Pa, PMD) daily, 400 mg moxifloxacin (M) and 1500 mg pyrazinamide (Z) for 6 months (6Pa200MZ) or 4 months (4Pa200MZ); 100 mg pretomanid daily for 4 months in the same combination (4Pa100MZ); or standard DS-TB treatment for 6 months. The primary outcome was treatment failure or relapse at 12 months post-randomisation. The non-inferiority margin for between-group differences was 12.0%. Recruitment was paused following three deaths and not resumed.RESULTS: Respectively 4/47 (8.5%), 11/57 (19.3%), 14/52 (26.9%) and 1/53 (1.9%) DS-TB outcomes were unfavourable in patients on 6Pa200MZ, 4Pa200MZ, 4Pa100MZ and controls. There was a 6.6% (95% CI -2.2% to 15.4%) difference per protocol and 9.9% (95%CI -4.1% to 23.9%) modified intention-to-treat difference in unfavourable responses between the control and 6Pa200MZ arms. Grade 3+ adverse events affected 68/203 (33.5%) receiving experimental regimens, and 19/68 (27.9%) on control. Ten of 203 (4.9%) participants on experimental arms and 2/68 (2.9%) controls died.CONCLUSION: PaMZ regimens did not achieve non-inferiority in this under-powered trial. An ongoing evaluation of PMD remains a priority.

Constitutive STAT3 Serine Phosphorylation Promotes Helicobacter-Mediated Gastric Disease

Gastric cancer is associated with chronic inflammation (gastritis) triggered by persistent Helicobacter pylori (H. pylori) infection. Elevated tyrosine phosphorylation of the latent transcription factor STAT3 is a feature of gastric cancer, including H. pylori-infected tissues, and aligns with nuclear transcriptional activity. However, the transcriptional role of STAT3 serine phosphorylation, which promotes STAT3-driven mitochondrial activities, is unclear. Here, by coupling serine-phosphorylated (pS)-STAT3-deficient Stat3^SA/SA mice with chronic H. felis infection, which mimics human H. pylori infection in mice, we reveal a key role for pS-STAT3 in promoting Helicobacter-induced gastric pathology. Immunohistochemical staining for infiltrating immune cells and expression analyses of inflammatory genes revealed that gastritis was markedly suppressed in infected Stat3^SA/SA mice compared with wild-type mice. Stomach weight and gastric mucosal thickness were also reduced in infected Stat3^SA/SA mice, which was associated with reduced proliferative potential of infected Stat3^SA/SA gastric mucosa. The suppressed H. felis-induced gastric phenotype of Stat3^SA/SA mice was phenocopied upon genetic ablation of signaling by the cytokine IL-11, which promotes gastric tumorigenesis via STAT3. pS-STAT3 dependency by Helicobacter coincided with transcriptional activity on STAT3-regulated genes, rather than mitochondrial and metabolic genes. In the gastric mucosa of mice and patients with gastritis, pS-STAT3 was constitutively expressed irrespective of Helicobacter infection. Collectively, these findings suggest an obligate requirement for IL-11 signaling via constitutive pS-STAT3 in Helicobacter-induced gastric carcinogenesis.

STAT3-driven hematopoiesis and lymphopoiesis abnormalities are dependent on serine phosphorylation

Deregulated activation of the latent transcription factor STAT3 has been implicated in the pathogenesis of myeloproliferative and lymphoproliferative hematologic disorders. The uncontrolled activation of STAT3 has traditionally been assigned to its elevated phosphorylation at tyrosine 705 (pY705) and associated nuclear transcriptional activity. By contrast, a transcriptional role for serine 727 phosphorylation (pS727) of STAT3 has recently emerged, suggesting that pS727 may account for the pathological activity of STAT3 in certain disease settings. Here, by coupling pS727-STAT3-deficient Stat3SA/SA mice with a STAT3-driven mouse model (gp130F/F) for myeloproliferative and lymphoproliferative pathologies, we reveal a key role for pS727-STAT3 in promoting multiple hematologic pathologies. The genetic blockade of pS727-STAT3 in gp130F/F:Stat3SA/SA mice ameliorated the neutrophilia, thrombocytosis, splenomegaly and lymphadenopathy that are features of gp130F/F mice. The protection against thrombocytosis in gp130F/F:Stat3SA/SA mice coincided with normalized megakaryopoiesis in both bone marrow and spleen compartments. Interestingly, pS727-STAT3-mediated abnormal lymphopoiesis in gp130F/F mice was more pronounced in lymph nodes compared to thymus, and was characterized by elevated numbers of B cells at the expense of T cells. Furthermore, pS727-STAT3 dependency for these hematologic pathologies coincided with transcriptional activity on STAT3-regulated genes, rather than its effect on mitochondrial and metabolic genes. Collectively, these findings suggest that pS727 plays a critical pathological role in modulating the transcriptional activity of STAT3 in hematologic disorders.

HIV testing uptake among the household contacts of multidrug-resistant tuberculosis index cases in eight countries

SETTING

The household contacts (HHCs) of multidrug-resistant tuberculosis (MDR-TB) index cases are at high risk of tuberculous infection and disease progression, particularly if infected with the human immunodeficiency virus (HIV). HIV testing is important for risk assessment and clinical management.

METHODS

This was a cross-sectional, multi-country study of adult MDR-TB index cases and HHCs. All adult and child HHCs were offered HIV testing if never tested or if HIV-negative >1 year previously when last tested. We measured HIV testing uptake and used logistic regression to evaluate predictors.

RESULTS

A total of 1007 HHCs of 284 index cases were enrolled in eight countries. HIV status was known at enrolment for 226 (22%) HHCs; 39 (4%) were HIV-positive. HIV testing was offered to 769 (98%) of the 781 remaining HHCs; 544 (71%) agreed to testing. Of 535 who were actually tested, 26 (5%) were HIV-infected. HIV testing uptake varied by site (median 86%, range 0-100%; P < 0.0001), and was lower in children aged <18 years than in adults (59% vs. 78%; adjusted for site P < 0.0001).

CONCLUSIONS

HIV testing of HHCs of MDR-TB index cases is feasible and high-yield, with 5% testing positive. Reasons for low test uptake among children and at specific sites-including sites with high HIV prevalence-require further study to ensure all persons at risk for HIV are aware of their status.

Reproducibility of CRISPR-Cas9 methods for generation of conditional mouse alleles: a multi-center evaluation

BACKGROUND

CRISPR-Cas9 gene-editing technology has facilitated the generation of knockout mice, providing an alternative to cumbersome and time-consuming traditional embryonic stem cell-based methods. An earlier study reported up to 16% efficiency in generating conditional knockout (cKO or floxed) alleles by microinjection of 2 single guide RNAs (sgRNA) and 2 single-stranded oligonucleotides as donors (referred herein as "two-donor floxing" method).

RESULTS

We re-evaluate the two-donor method from a consortium of 20 laboratories across the world. The dataset constitutes 56 genetic loci, 17,887 zygotes, and 1718 live-born mice, of which only 15 (0.87%) mice contain cKO alleles. We subject the dataset to statistical analyses and a machine learning algorithm, which reveals that none of the factors analyzed was predictive for the success of this method. We test some of the newer methods that use one-donor DNA on 18 loci for which the two-donor approach failed to produce cKO alleles. We find that the one-donor methods are 10- to 20-fold more efficient than the two-donor approach.

CONCLUSION

We propose that the two-donor method lacks efficiency because it relies on two simultaneous recombination events in cis, an outcome that is dwarfed by pervasive accompanying undesired editing events. The methods that use one-donor DNA are fairly efficient as they rely on only one recombination event, and the probability of correct insertion of the donor cassette without unanticipated mutational events is much higher. Therefore, one-donor methods offer higher efficiencies for the routine generation of cKO animal models.

Resource utilization for multidrug-resistant tuberculosis household contact investigations (A5300/I2003)

BACKGROUND

Current guidelines recommend evaluation of the household contacts (HHCs) of individuals with multidrug-resistant tuberculosis (MDR-TB); however, implementation of this policy is challenging.

OBJECTIVE

To describe the resource utilization and operational challenges encountered when identifying and characterizing adult MDR-TB index cases and their HHCs.

DESIGN

Cross-sectional study of adult MDR-TB index cases and HHCs at 16 clinical research sites in eight countries. Site-level resource utilization was assessed with surveys.

RESULTS

Between October 2015 and April 2016, 308 index cases and 1018 HHCs were enrolled. Of 280 index cases with sputum collected, 94 were smear-positive (34%, 95%CI 28-39), and of 201 with chest X-rays, 87 had cavitary disease (43%, 95%CI 37-50) after a mean duration of treatment of 8 weeks. Staff required 512 attempts to evaluate the 308 households, with a median time per attempt of 4 h; 77% (95%CI 73-80) of HHCs were at increased risk for TB: 13% were aged <5 years, 8% were infected with the human immunodeficiency virus, and 79% were positive on the tuberculin skin test/interferon-gamma release assay. One hundred and twenty-one previously undiagnosed TB cases were identified. Issues identified by site staff included the complexity of personnel and participant transportation, infection control, personnel safety and management of stigma.

CONCLUSION

HHC investigations can be high yield, but are labor-intensive.

Pretreatment chest x-ray severity and its relation to bacterial burden in smear positive pulmonary tuberculosis

BACKGROUND

Chest radiographs are used for diagnosis and severity assessment in tuberculosis (TB). The extent of disease as determined by smear grade and cavitation as a binary measure can predict 2-month smear results, but little has been done to determine whether radiological severity reflects the bacterial burden at diagnosis.

METHODS

Pre-treatment chest x-rays from 1837 participants with smear-positive pulmonary TB enrolled into the REMoxTB trial (Gillespie et al., N Engl J Med 371:1577-87, 2014) were retrospectively reviewed. Two clinicians blinded to clinical details using the Ralph scoring system performed separate readings. An independent reader reviewed discrepant results for quality assessment and cavity presence. Cavitation presence was plotted against time to positivity (TTP) of sputum liquid cultures (MGIT 960). The Wilcoxon rank sum test was performed to calculate the difference in average TTP for these groups. The average lung field affected was compared to log ₁₀ TTP by linear regression. Baseline markers of disease severity and patient characteristics were added in univariable regression analysis against radiological severity and a multivariable regression model was created to explore their relationship.

RESULTS

For 1354 participants, the median TTP was 117 h (4.88 days), being 26 h longer (95% CI 16-30, p < 0.001) in patients without cavitation compared to those with cavitation. The median percentage of lung-field affected was 18.1% (IQR 11.3-28.8%). For every 10-fold increase in TTP, the area of lung field affected decreased by 11.4%. Multivariable models showed that serum albumin decreased significantly as the percentage of lung field area increased in both those with and without cavitation. In addition, BMI and logged TTP had a small but significant effect in those with cavitation and the number of severe TB symptoms in the non-cavitation group also had a small effect, whilst other factors found to be significant on univariable analysis lost this effect in the model.

CONCLUSIONS

The radiological severity of disease on chest x-ray prior to treatment in smear positive pulmonary TB patients is weakly associated with the bacterial burden. When compared against other variables at diagnosis, this effect is lost in those without cavitation. Radiological severity does reflect the overall disease severity in smear positive pulmonary TB, but we suggest that clinicians should be cautious in over-interpreting the significance of radiological disease extent at diagnosis.

Knockout of the epilepsy gene Depdc5 in mice causes severe embryonic dysmorphology with hyperactivity of mTORC1 signalling

DEPDC5 mutations have recently been shown to cause epilepsy in humans. Evidence from in vitro studies has implicated DEPDC5 as a negative regulator of mTORC1 during amino acid insufficiency as part of the GATOR1 complex. To investigate the role of DEPDC5 in vivo we generated a null mouse model using targeted CRISPR mutagenesis. Depdc5 homozygotes display severe phenotypic defects between 12.5-15.5 dpc, including hypotrophy, anaemia, oedema, and cranial dysmorphology as well as blood and lymphatic vascular defects. mTORC1 hyperactivity was observed in the brain of knockout embryos and in fibroblasts and neurospheres isolated from knockout embryos and cultured in nutrient deprived conditions. Heterozygous mice appeared to be normal and we found no evidence of increased susceptibility to seizures or tumorigenesis. Together, these data support mTORC1 hyperactivation as the likely pathogenic mechanism that underpins DEPDC5 loss of function in humans and highlights the potential utility of mTORC1 inhibitors in the treatment of DEPDC5-associated epilepsy.

Two-stage activity-safety study of daily rifapentine during intensive phase treatment of pulmonary tuberculosis

BACKGROUND

Rifapentine (RPT) has potent activity against Mycobacterium tuberculosis; however, the optimal dose for anti-tuberculosis treatment is unknown.

OBJECTIVE

To determine the antimicrobial activity, safety and tolerability of RPT 450 mg or 600 mg administered daily during the first 8 weeks of treatment for pulmonary tuberculosis (TB).

DESIGN

In a two-stage, randomised open-label study, adults with sputum smear-positive TB were randomised to receive RPT 450 mg, RPT 600 mg or rifampicin (RMP) 600 mg daily for 8 weeks with isoniazid, pyrazinamide and ethambutol. The primary endpoint was sputum culture status on Löwenstein-Jensen (LJ) medium at completion of 8 weeks of treatment.

RESULTS

A total of 153 participants were enrolled. Both RPT regimens met pre-specified criteria to advance to stage 2. At completion of 8 weeks of treatment, LJ culture conversion occurred in 85% (35/41), 96% (43/45) and 94% (34/36) of participants in the RPT 450 mg, RPT 600 mg and RMP groups, respectively. The proportions of participants discontinuing treatment were similar (respectively 1/54 [2.0%], 1/51 [2.0%] and 4/48 [8.3%] in the RPT 450 mg, RPT 600 mg and RMP groups), as were ⩾grade 3 adverse events (0/54 [0%], 1/51 [2.0%] and 4/48 [8.3%]).

CONCLUSIONS

There was a trend towards greater efficacy with RPT 600 mg than with RPT 450 mg. Daily RPT was safe and well-tolerated.

Elevated IP-10 and IL-6 from bronchoalveolar lavage cells are biomarkers of non-cavitary tuberculosis

BACKGROUND

Active TB disease can destroy lung parenchyma leading to cavities. Immune responses that predispose or protect individuals from lung damage during TB are poorly defined.

OBJECTIVE

To sample lung immune cells and assay bronchoalveolar lavage (BAL) cell cytokine production.

DESIGN

Enrolled subjects (n = 73) had bilateral infiltrates and underwent BAL.

RESULTS

All had sputum culture demonstrating Mycobacterium tuberculosis and 22/73 (30%) had cavities on their chest radiograph. Those with cavities at presentation had a higher percentage of polymorphonuclear neutrophils (PMN) in BAL as well as lower inducible protein (IP) 10 (P < 0.01) and interleukin (IL) 6 (P = 0.013) in BAL cell supernatants compared to those without cavities. There was no correlation between cavities and other BAL or serum cytokines. IP-10 was negatively associated with BAL PMN. IP-10 and IL-6 expression above median reduces the odds of cavities by 79% and 78% in logistic regression models. IP-10 and IL-6 clustered with interferon-gamma and tumour necrosis factor-alpha in a principal component analysis, while IL-4 clustered with PMN.

CONCLUSION

Increasing IP-10 and IL-6 production by BAL cells is associated with non-cavitary TB in patients who present with radiographically advanced TB. IP-10 and IL-6 may reflect an effective T-helper 1 immune control pathway for TB, attenuating tuberculous lung destruction.

Evidence-based consensus on the insertion of central venous access devices: definition of minimal requirements for training

There is a lack of standard minimal requirements for the training of insertion techniques and maintenance of central venous access devices (CVADs). An international evidence-based consensus task force was established through the World Congress of Vascular Access (WoCoVA) to provide definitions and recommendations for training and insertion of CVADs. Medical literature published from February 1971 to April 2012 regarding 'central vascular access', 'training', 'competency', 'simulation', and 'ultrasound' was reviewed on Pubmed, BioMed Central, ScienceDirect, and Scopus databases. The GRADE and the GRADE-RAND methods were utilized to develop recommendations. Out of 156 papers initially identified, 83 papers described training for central vascular access placement. Sixteen recommendations are proposed by this task force, each with an evidence level, degree of consensus, and recommendation grade. These recommendations suggest central venous access education include didactic or web-based teaching with insertion procedure, infection prevention, complications, care, and maintenance of devices, along with laboratory models and tools for simulation practice incorporating ultrasound. Clinical competence should be determined by observation during clinical practice using a global rating scale rather than by the number of procedures performed. Ensuring safe insertion and management of central venous devices requires standardized education, simulation practice, and supervised insertions.

A systematic review on the use of prophylactic mesh during primary stoma formation to prevent parastomal hernia formation

AIM

Despite advances in surgical technique, parastomal herniation is common. This systematic review aims to assess the efficacy of prophylactic mesh at primary operation in reducing the incidence of parastomal hernia.

METHOD

Medline, EMBASE and CENTRAL were searched for relevant publications between January 1980 and January 2010. The search strategy included text terms and MESH headings for parastomal hernia, mesh and prevention and/or prophylaxis of hernia. No language restrictions were applied. Bibliographies from the papers requested in full were manually checked. All randomized controlled trials were included regardless of the language of publication. Results were extracted from the papers by two observers independently on a predefined data sheet. Disagreements were resolved by discussion. REVMAN 5 was used for statistical analysis.

RESULTS

Of 27 possible studies three randomized controlled trials fulfilled the criteria for systematic review, with a total of 128 patients (mesh 64, no mesh 64). The two study groups were well matched demographically. The incidence of parastomal hernia in the mesh group was 12.5% (8/64) compared with 53% (34/64) in the control group (P < 0.0001). There was no difference in mesh related morbidity in the two groups.

CONCLUSION

Although only three trials with 128 patients fulfilled the criteria for this systematic review, the data suggest that the use of prophylactic prosthetic mesh at the time of primary stoma formation reduces the incidence of parastomal hernia.

Laparoscopic fellowship training can deliver a competent laparoscopic surgeon and trainer

AIM

The study investigated whether experience gained during a UK laparoscopic colorectal fellowship enabled the fellow subsequently to train consultant colleagues in laparoscopic surgery.

METHOD

In one unit a newly appointed post-laparoscopic fellowship consultant (PFC) mentored his other two colleagues. Prospectively collected data regarding surgical outcome were compared with those of the year preceding the PFC appointment.

RESULTS

In the preceding year 18.5% of 260 resections were attempted laparoscopically. This increased to 92.6% (of 270) in the year after (P < 0.0001). Respective conversion rates were 4.2% and 8.4% (P = 0.5524). In the first 6 months after PFC appointment, mentored consultants performed 23 supervised cases. In the second 6 months they carried out 58 procedures independently and trainees performed 38 supervised cases. There was no significant difference in anastomotic leakage and readmission and 30-day mortality rates between the pre- and post-PFC periods.

CONCLUSION

A laparoscopic fellowship enables the PFC to mentor consultant colleagues safely and effectively.

Early bactericidal activity of delamanid (OPC-67683) in smear-positive pulmonary tuberculosis patients

BACKGROUND

Delamanid (OPC-67683) is a novel mycolic acid biosynthesis inhibitor active against Mycobacterium tuberculosis at a low minimum inhibitory concentration.

METHODS

Forty-eight patients with smear-positive tuberculosis (63% male; 54.7 ± 9.9 kg; 30.7 ± 10.8 years) were randomly assigned to receive delamanid 100, 200, 300 or 400 mg daily for 14 days. Colony forming units (cfu) of M. tuberculosis were counted on agar plates from overnight sputum collections to calculate early bactericidal activity (EBA), defined as fall in log(10) cfu/ml sputum/day.

RESULTS

The EBA of delamanid was monophasic and not significantly different between dosages; however, more patients receiving 200 mg (70%) and 300 mg (80%) experienced a response of ≥0.9 log(10) cfu/ml sputum decline over 14 days than those receiving 100 mg (45%) and 400 mg (27%). The average EBA of all dosages combined (0.040 ± 0.056 log(10) cfu/ml sputum/day) was significant from day 2 onward. Delamanid exposure was less than dosage-proportional, reaching a plateau at 300 mg, likely due to dose-limited absorption. Moderate but significant correlation was found between C(max) and EBA, indicating exposure dependence. Delamanid was well tolerated without significant toxicity.

CONCLUSIONS

Delamanid at all dosages was safe, well tolerated and demonstrated significant exposure-dependent EBA over 14 days, supporting further investigation of its pharmacokinetics and anti-tuberculosis activity.

Are interferon-γ release assays useful for diagnosing active tuberculosis in a high-burden setting?

Although interferon-γ release assays (IGRAs) are intended for diagnosing latent tuberculosis (TB), we hypothesised that in a high-burden setting: 1) the magnitude of the response when using IGRAs can distinguish active TB from other diagnoses; 2) IGRAs may aid in the diagnosis of smear-negative TB; and 3) IGRAs could be useful as rule-out tests for active TB. We evaluated the accuracy of two IGRAs (QuantiFERON®-TB Gold In-tube (QFT-GIT) and T-SPOT®.TB) in 395 patients (27% HIV-infected) with suspected TB in Cape Town, South Africa. IGRA sensitivity and specificity (95% CI) were 76% (68-83%) and 42% (36-49%) for QFT-GIT and 84% (77-90%) and 47% (40-53%) for T-SPOT®.TB, respectively. Although interferon-γ responses were significantly higher in the TB versus non-TB groups (p<0.0001), varying the cut-offs did not improve discriminatory ability. In culture-negative patients, depending on whether those with clinically diagnosed TB were included or excluded from the analysis, the negative predictive value (NPV) of QFT-GIT, T-SPOT®.TB and chest radiograph in smear-negative patients varied between 85 and 89, 87 and 92, and 98% (for chest radiograph), respectively. Overall accuracy was independent of HIV status and CD4 count. In a high-burden setting, IGRAs alone do not have value as rule-in or -out tests for active TB. In smear-negative patients, chest radiography had better NPV even in HIV-infected patients.

High prevalence of smoking among patients with suspected tuberculosis in South Africa

There is growing evidence that tobacco smoking is an important risk factor for tuberculosis (TB). There are no data validating the accuracy of self-reported smoking in TB patients and limited data about the prevalence of smoking in TB patients from high-burden settings. We performed a cross-sectional analysis of 500 patients with suspected TB in Cape Town, South Africa. All underwent comprehensive diagnostic testing. The accuracy of their self-reported smoking status was determined against serum cotinine levels. Of the 424 patients included in the study, 56 and 60% of those with active and latent TB infection (LTBI), respectively, were current smokers. Using plasma cotinine as a reference standard, the sensitivity of self-reported smoking was 89%. No statistically significant association could be found between smoking and active TB or LTBI. In Cape Town, the prevalence of smoking among patients with suspected and confirmed TB was much higher than in the general South African population. Self-reporting is an accurate measure of smoking status. These results suggest the need to actively incorporate tobacco cessation programmes into TB services in South Africa.

Inflammatory bowel disease in young people: the case for transitional clinics

BACKGROUND

The incidence of inflammatory bowel disease (IBD) is increasing among adolescents. In all, 25% of patients are diagnosed before the age of 16, when they are traditionally transferred from the pediatric to the adult service.

METHODS

We conducted a retrospective case-controlled study to characterize patients treated in a novel transitional adolescent-young adult IBD clinic. This compared disease extent, radiation exposure, therapeutic strategy, and requirement for surgery in 100 adolescents with controls from our adult IBD clinic matched for disease duration.

RESULTS

The median (range) ages for the adolescent and adult population was 19 (16-28) and 43 (24-84), with a median age at diagnosis of 15 (3-26) and 39 (13-82) respectively (P < 0.001). Crohn's disease was significantly more common in the adolescents. Disease distribution was ileocolonic in 69% of adolescents and 28% of adults, restricted to the ileum in 20% of adolescents and 47% of adults, and colonic only in 11% and 22%, respectively. Upper gastrointestinal involvement occurred in 23% of adolescents, but was not seen in adults (P < 0.01). Total ulcerative colitis was seen in 67% of adolescents and 44% of adults (P < 0.01). Contrary to previous data adolescents did not receive more ionizing radiation than adults. Requirement for immunosuppressive therapy was higher in the adolescent group (53% versus 31%, respectively, P < 0.01). Likewise, 20% of adolescents had required biological therapy compared to only 8% in the adult cohort (P < 0.05).

CONCLUSIONS

Gastroenterologists should recognize that IBD is more complex when presenting in adolescence and our data support the creation of specific adolescent transitional clinics.

Chest radiograph reading and recording system: evaluation for tuberculosis screening in patients with advanced HIV

SETTING

An antiretroviral treatment (ART) service in Gugulethu township, Cape Town, South Africa.

OBJECTIVE

To assess the inter-observer agreement when using the chest radiographic reading and reporting system (CRRS) to detect radiographic abnormalities in patients with advanced human immunodeficiency virus (HIV) associated immunodeficiency being actively screened for tuberculosis (TB). Second, to assess the associated performance characteristics of radiology as a routine screening test for detection of culture-confirmed pulmonary TB.

DESIGN

Radiographs from a study in which patients were actively screened for TB just before starting ART were independently reported by two CRRS-certified readers blinded to clinical status.

RESULTS

Good kappa statistic agreements between observers were found when reporting any radiological abnormality consistent with TB among all patients (n = 203, kappa = 0.63, 95%CI 0.52-0.73) and among those with culture-confirmed TB (n = 53, kappa = 0.61, 95%CI 0.40-0.83). However, in comparison with sputum culture, the sensitivity (0.68, 95%CI 0.54-0.79) and specificity (0.53, 95%CI 0.45-0.61) of radiology in this patient group were low.

CONCLUSION

This study provides evidence of the good inter-observer agreement using the CRRS standardised reporting methodology when used among patients with advanced HIV-associated immunodeficiency and a high prevalence of culture-proven pulmonary TB. The utility of radiology as a screening test for TB in this patient group, however, remains limited.

Shipboard testing of the efficacy of SeaKleen as a ballast water treatment to eliminate non-indigenous species aboard a working tanker in Pacific waters

Trials were conducted aboard the tanker Seabulk Mariner to test a natural product, SeaKleen, as a biocide controlling non-indigenous populations of plankton and bacteria in ballast water. SeaKleen was dosed into matched ballast tanks at two different concentrations, 0.8 mg L(-1) active ingredient (a.i.) and 1.6 mg L(-1) a.i. during ballasting off the Oregon coast during a three-day passage to Prince William Sound, Alaska. Live organism counts from treated ballast water were compared with those from untreated (control tank) water collected from the same source location. Shipboard chemical analyses were made to verify dose and quantify chemical degradation and residuals following dilution. Results indicated that both SeaKleen doses resulted in complete zooplankton and phytoplankton mortality and that the higher dose (1.6 mg L(-1) a.i.) caused a two-log removal of culturable bacteria over a 92 h grow-out period. Spectrophotometry confirmed initial dosing to within 5% of nominal values. Shipboard bioassays were conducted using larval fish (Cyprinodon variegatus), brine shrimp (Artemia salina) and the bioluminescent dinoflagellate Pyrocystis lunula. Exposure of the test organisms to water drawn from treated ballast tanks 48 h after SeaKleen was added to the tanks resulted in 100% mortalities in Cyprinodon and Pyrocystis at both doses. Corresponding mortalities for Artemia larvae were 100% and 60% for high and low SeaKleen doses, respectively. Toxicity testing of treated water, subjected to varying dilutions, indicated that residual toxicity to even the most sensitive organisms would be eliminated once the discharge had dispersed beyond 100 feet from the vessel.

Adverse events to antituberculosis therapy: influence of HIV and antiretroviral drugs

This study investigated whether serious adverse events (SAEs) during antituberculosis therapy occur more frequently in HIV co-infected patients in a South African population. A retrospective analysis examined incidences of hepatotoxicity, peripheral neuropathy, severe arthralgia, persistent vomiting and severe rash in 400 patients treated for tuberculosis in a community clinic. A total of 141 patients were co-infected with HIV, among whom only 16.3% were receiving antiretrovirals. Details of SAEs were ascertainable in 331/400 patients, and occurred in 26.7% of HIV-infected and 13.3% of HIV-uninfected individuals ( P = 0.003). The excess was attributable to increased peripheral neuropathy (8.3% and 1.9%, respectively, P = 0.009) and persistent vomiting (13.3% and 3.3%, P = 0.001). SAE occurrence was not related to antiretroviral use, although median CD4 counts were lower in those experiencing side-effects (130 and 259 cells/µL, P = 0.008). The treatment completion did not differ significantly between the two groups (76.6% and 84.2%, P = 0.08).

The diagnostic value of digital rectal examination in primary care for palpable rectal tumour

BACKGROUND

Accurate digital rectal examination (DRE) enables the early diagnosis of palpable rectal tumour. We aimed at evaluating the diagnostic value of DRE performed by general practitioners (GPs), with respect to detecting the presence of a palpable rectal tumour.

METHOD

All patients diagnosed to have a palpable rectal tumour via a 14-day cancer referral system between May and December 2006 were identified from the colorectal database. Patients referred by GPs during the same period as having a palpable rectal tumour were also identified by reviewing the 14-day cancer referrals. Sensitivity, specificity, positive and negative predictive value of a DRE in primary care were calculated by using these data.

RESULTS

Between May and December 2006, 1069 patients were referred to the University Hospital of North Staffordshire to the 14-day urgent colorectal cancer referral service. Of these, 108 patients were referred as having a 'palpable rectal tumour'. Only 32 of the 108 were found to have a rectal lesion on examination in the hospital. Ten tumours were missed by GPs' DREs.

CONCLUSION

Digital rectal examination in primary care for palpable rectal tumour has a sensitivity of 0.762, specificity of 0.917, positive predictive value of 0.296 and negative predictive value of 0.988. It is an inaccurate procedure and a poor predictor for palpable rectal tumour.

The influence of water quality on the toxicity and degradation of juglone (5-hydroxy 1,4-naphthoquinone)

This study was part of a broader investigation of low molecular weight quinones under consideration as biocides for the control of aquatic nuisance species (ANS). Preliminary investigations identified the 2-ring naphthoquinones as broad spectrum biocides controlling a wide range of aquatic organisms. All biocides were relatively short-lived in saline waters, with half-lives between 5 and 30h. Juglone (5-hydroxy 1,4-naphthoquinone) and plumbagin (5-hydroxy-2-methyl-1,4- naphthoquinone) showed the greatest toxicity against most aquatic organisms. These qualities formed the basis for a patent focusing on these two compounds as biocides for ANS control, with juglone identified as the more cost-effective of the two. Although juglone has been extensively studied as a plant toxin and reducing agent, remarkably little information exists on its use as an aquatic biocide. We describe the toxicity of juglone over the range of water quality parameters likely to be encountered in ballast water, a major vector for ANS. Tests indicated that its molecular stability was enhanced in freshwater and particularly under neutral to acid conditions. This was supported by results of bioassays on the freshwater cladoceran Daphnia magna that indicated enhanced juglone toxicity at pHs of < or =6.7. A low octanol:water partition coefficient for juglone indicated little capacity for these compounds to be adsorbed by suspended particulates and for bioaccumulation. These properties together with their relatively rapid degradation (t1/2 < or =30h), particularly in the marine environment, indicated a low the risk of residual toxicity associated with the release of juglone-treated water.

Adsorption and absorption of polycyclic aromatic hydrocarbons to rice roots

Rice roots and surrounding air, soil and water samples were collected for polycyclic aromatic hydrocarbon (PAH) analysis. The rice roots were separated into lateral roots and nodal roots, and the PAH concentration in the former was found to be higher than that in the latter. In addition, root physiological characteristics including root biotic mass, root lipid content and specific surface area are also discussed. When normalizing the total, adsorption and absorption PAH fractions on a dry root weight basis to root biomass, root lipid, and surface area bases respectively, the differences between PAHs in the two types of roots diminished by 2 to 3 times on average. Results from sequential extraction indicated that PAHs were more easily absorbed by interior rice roots than adsorbed on the surface. In addition, more than 60% of total PAHs accumulated in root tissue for both lateral and nodal roots. However, the results were highly related to the solvent used, extraction time and methodology. Correlation analysis between bioconcentration factors (root over environment) and K(OA), K(OW) showed water to be more significant for PAH adsorption in rice roots than other environmental media.