Impaired intestinal gas propulsion in manometrically proven dysmotility and in irritable bowel syndrome

BACKGROUND

Intestinal manometry is the current gold standard for diagnosing small bowel dysmotility; however, the functional significance of abnormal manometry is unknown. Our aim was to determine whether, and to what extent, intestinal gas propulsion is impaired in patients with manometrically proven dysmotility compared with healthy controls and patients with IBS.

METHODS

Clearance and tolerance of a jejunal gas load (12 mL min(-1) for 2 h) were measured in 15 patients with severe abdominal symptoms and intestinal dysmotility evidenced by manometry, 15 patients with IBS and 15 healthy subjects. Thereafter, the effect of neostigmine (0.5 mg i.v. bolus) vs placebo (i.v. saline) was tested in six dysmotility patients.

KEY RESULTS

After 2-h gas infusion, patients with dysmotility developed significantly more gas retention (717 +/- 91 mL) than IBS patients (372 +/- 82 mL; P = 0.0037) and healthy subjects (17 +/- 67 mL; P < 0.0001 vs dysmotility; P = 0.0060 vs IBS). Despite the greater retention in dysmotility patients, abdominal perception (2.5 +/- 0.6 score) and distension (7 +/- 2 mm girth increment) were similar to IBS (3.9 +/- 0.6 score and 7 +/- 2 mm, respectively). In dysmotility patients, neostigmine produced immediate clearance of gas, and by 30 min had reduced gas retention (by -552 +/- 182 vs 72 +/- 58 mL after saline; P = 0.008), abdominal symptoms (by -0.8 +/- 0.3 score vs 0.3 +/- 0.2 after saline; P = 0.019) and distension (girth change -5 +/- 1 mm; P = 0.003 vs-2 +/- 2 mm after saline).

CONCLUSION & INFERENCES

Patients with manometric dysmotility have markedly impaired intestinal gas propulsion. In IBS patients, impaired gas propulsion is less pronounced but associated with concomitant sensory dysfunction and poor tolerance of gas retention.

PROMO: Real-time prospective motion correction in MRI using image-based tracking

Artifacts caused by patient motion during scanning remain a serious problem in most MRI applications. The prospective motion correction technique attempts to address this problem at its source by keeping the measurement coordinate system fixed with respect to the patient throughout the entire scan process. In this study, a new image-based approach for prospective motion correction is described, which utilizes three orthogonal two-dimensional spiral navigator acquisitions, along with a flexible image-based tracking method based on the extended Kalman filter algorithm for online motion measurement. The spiral navigator/extended Kalman filter framework offers the advantages of image-domain tracking within patient-specific regions-of-interest and reduced sensitivity to off-resonance-induced corruption of rigid-body motion estimates. The performance of the method was tested using offline computer simulations and online in vivo head motion experiments. In vivo validation results covering a broad range of staged head motions indicate a steady-state error of less than 10% of the motion magnitude, even for large compound motions that included rotations over 15 deg. A preliminary in vivo application in three-dimensional inversion recovery spoiled gradient echo (IR-SPGR) and three-dimensional fast spin echo (FSE) sequences demonstrates the effectiveness of the spiral navigator/extended Kalman filter framework for correcting three-dimensional rigid-body head motion artifacts prospectively in high-resolution three-dimensional MRI scans.

Local B cells and IgE production in the oesophageal mucosa in eosinophilic oesophagitis

BACKGROUND

Eosinophilic oesophagitis (EO) is an emerging yet increasingly prevalent disorder characterised by a dense and selective eosinophilic infiltration of the oesophageal wall. While EO is considered an atopic disease primarily triggered by food antigens, disparities between standard allergen testing and clinical responses to exclusion diets suggest the participation of distinct antigen-specific immunoglobulin E (IgE) in the pathophysiology of EO.

AIM

To find evidence for a local IgE response.

METHODS

Endoscopic biopsies of the distal oesophagus of atopic and non-atopic EO and control individuals (CTL) were processed for immunohistochemistry and immunofluorescence to assess the presence of B cells, mast cells, and IgE-bearing cells. Oesophageal RNA was analysed for the expression of genes involved in B cell activation, class switch recombination to IgE and IgE production, including germline transcripts (GLTs), activation-induced cytidine deaminase (AID), IgE heavy chain (Cepsilon) and mature IgE mRNA using polymerase chain reaction and microarray analysis.

RESULTS

Regardless of atopy, EO showed increased density of B cells (p<0.05) and of IgE-bounded mast cells compared to CTL. Both EO and CTL expressed muGLT, epsilonGLT, gamma4GLT, AID, Cepsilon and IgE mRNA. However, the frequency of expression of total GLTs (p = 0.002), epsilonGLT (p = 0.024), and Cepsilon (p = 0.0003) was significantly higher in EO than in CTL, independent of the atopic status.

CONCLUSION

These results support the heretofore unproven occurrence of both local immunoglobulin class switching to IgE and IgE production in the oesophageal mucosa of EO patients. Sensitisation and activation of mast cells involving local IgE may therefore critically contribute to disease pathogenesis.

Very low prevalence and no clinical significance of occult hepatitis B in a cohort of HIV-infected patients with isolated anti-HBc seropositivity: the BHOI study

PURPOSE

Data on occult HBV infection in HIV patients are conflicting. We aimed to analyse the prevalence and clinical significance of occult hepatitis B in HIV-infected subjects.

METHOD

An open-label, cross-sectional, multicentre study including all subjects with isolated anti-HBc seropositivity from a cohort of 3,030 HIV-infected patients was undertaken. HBsAg and HBsAb were both negative in all cases, and those patients with acute or convalescent hepatitis B were excluded. HBV DNA was quantified by PCR with a detection limit of 20 IU/mL.

RESULTS

We found 5 cases (2.5%) of occult hepatitis B among 202 HIV-patients with isolated anti-HBc. The mean HBV DNA was 66 (15-112) IU/mL, none had symptomatic hepatitis, and their features, including aminotransferase levels, were similar to those without occult HBV infection.

CONCLUSIONS

Occult hepatitis due to HBV is very unusual in HIV-positive patients with isolated anti-HBc. The use of standard regimens of HAART including drugs with activity against HBV might underestimate the prevalence of occult HBV infection. These patients had a very low viral load, no identifiable risk factors, and no greater risk of hypertransaminasaemia or the development of symptomatic hepatitis.

Mycobacterium gordonae urinary infection in a renal transplant recipient

The authors present a case of urinary infection by a non-tuberculous mycobacteria (NTM) species, Mycobacterium gordonae, in a renal transplant recipient. A 29-year-old female patient had persistent sterile pyuria after her second kidney transplant. An NTM, M. gordonae, was isolated, and the patient was started on antituberculous treatment, with resolution of leukocyturia. Ureteral stenosis with hydronephrosis and deterioration of allograft function was diagnosed later on and, despite the introduction of intraureteral catheter and resolution of hydronephrosis, there was no recovery of baseline renal function. She ultimately resumed dialysis after a severe pyelonephritis. The authors discuss the problems of establishing diagnosis of infection (versus colonization) by NTM and highlight the difficulty of treating these infections, especially because of the possible interaction with immunosuppressant agents, facilitating anti-allograft immune response.

Effectiveness and safety of simplification from tenofovir-lamivudine (TDF-3TC) to tenofovir-emtricitabine (TDF-FTC) co-formulation (Truvada) in virologically suppressed HIV-infected patients on HAART

The objective was to evaluate the effectiveness and safety of simplification from tenofovir-lamivudine (TDF-3TC) to Truvada (TVD) in virologically suppressed HIV patients. We carried out an open-label, multicentre, non-controlled study of HIV patients on a stable regimen including TDF-3TC who switched from TDF-3TC to TVD. Viral load responses at 24 and 48 weeks were evaluated. Changes in the calculated glomerular filtration rates (cGFR; Cockcroft-Gault equation) were analysed at baseline and at 24 and 48 weeks. Patients with drug-related nephrotoxicity (cGFR < 60 mL/min at 48 weeks or interruption of TVD because of renal toxicity) were analysed in detail. Two hundred and ninety-five patients with a mean time on TDF-3TC of 19.9 months (range 8.8-29.8) were enrolled. The third drug was a non-nucleoside reverse transcriptase inhibitor, which was administered to 187 patients (76.4% efavirenz) and a protease inhibitor was administered to 108 (43.5% lopinavir/ritonavir). At 48 weeks, 85.7% of the patients were still taking the same regimen, all with an undetectable viral load. The cGFR (mL/min) decreased from baseline (111 [89-130]) to 48 weeks (105 [84-121]); p < 0.0001. The percentage of patients with a cGFR <60 mL/min at 48 weeks was 3.5. Six patients ceased TVD because of drug-related nephrotoxicity. The only factors associated with nephrotoxicity were age, baseline weight and cGFR. Simplification from TDF-3TC to TVD was associated with a decrease in cGFR, with a low prevalence of nephrotoxicity at 48 weeks.

Long-term prognosis of HIV-infected patients with Kaposi sarcoma treated with pegylated liposomal doxorubicin

INTRODUCTION

Incidence of Kaposi sarcoma (KS) in human immunodeficiency virus (HIV)-infected persons has dramatically decreased in the highly active antiretroviral therapy era. However, this tumor still represents the most common cancer in this population.

OBJECTIVES

The objectives of this study were to evaluate long-term prognosis of HIV-infected patients with KS who had received pegylated liposomal doxorubicin (PLD) and, more specifically, to assess tumor relapse rate, mortality, and cause of death in these subjects.

DESIGN

This study was a retrospective review of all patients with KS who had received PLD in centers belonging to the Caelyx/KS Spanish Group. Kaplan-Meier analysis and univariate and multivariate Cox-regression analysis were used to assess the rate of and factors associated with relapse and death through January 2006.

RESULTS

A total of 98 patients received PLD from September 1997 through June 2002. Median follow-up after initiation of treatment was 28.7 months (interquartile range, 6.6-73.2 months); during follow-up, 29 patients died (a mortality rate of 14.6% per year). In 9 patients (31%), the cause of death was related to the appearance of other tumors (including 7 lymphomas, 1 gastrointestinal adenocarcinoma, and 1 tongue epidermoid cancer). Death caused by progression of KS occurred in 3 cases. Death risk was inversely related to CD4(+) cell counts at the end of follow-up (hazard ratio for every increase in CD4(+) cell count of 100 cells/microL, 0.7; 95% confidence interval, 0.5-0.9). A relapse study was performed for 61 patients who had complete or partial response to PLD and who attended a control visit after treatment completion. After a median follow-up of 50 months (interquartile range, 17.2-76 months), 8 patients (13%) had experienced relapse; 5 of these patient experienced relapse within the first year after stopping PLD. The only factor that was independently related to risk of relapse was having a CD4(+) cell count >200 cells/microL at baseline (hazard ratio, 6.2; 95% confidence interval, 1.2-30). Lower CD4(+) cell count at the end of follow-up was marginally associated with relapse (hazard ratio for every increase in CD4(+) cell count of 100 cells/microL, 0.7; 95% confidence interval, 0.6-1.01).

CONCLUSIONS

Treatment of KS with PLD in HIV-infected patients is followed by a low relapse rate, with most relapses occurring during the first year after stopping chemotherapy. However, the mortality rate in this population was high, in part because of an unexpectedly high incidence of other tumors, mainly lymphomas.

Impact assessment in living kidney donation: psychosocial aspects in the donor

BACKGROUND

Living donor kidney transplantation has a positive influence on graft survival and recipient quality of life (QoL). We assessed the psychosocial impact of donation to the donor.

METHODS

Before and after the procedure 32 living kidney donors (mean age 41 years) completed the Zung Self-Rating Anxiety and Depression Scales; a Sociodemographic, Short-Form 36 Health Survey (SF-36), and a Donation Perceptions Questionnaire.

RESULTS

Living kidney donors were siblings (62.5%), parents (34.4%), or a daughter (3.1%). Transplantation was not successful in two cases: one recipient death and one graft failure. No significant changes were observed in donor QoL except for the SF-36 social functioning subscale that showed significant improvement after donation (P = .038). A reduction in depression symptom frequency was verified after donation (from 65.6% to 46.9%). There was an almost significant decrease in depression scores (P = .077), which was in fact was significant when one considered only successful transplants (P = .021). There was no significant variation in anxiety scores among donors. Time since transplantation was inversely correlated with overall anxiety (r = .443, P = .011), and with somatic anxiety subscales (r = .357, P = .045). For most donors, the decision to donate was easy and spontaneous. Nearly all donors would donate again and strongly encourage others to donate.

CONCLUSIONS

Except for the social functioning scale that improved, no significant changes were observed in QoL of living kidney donors after the procedure. Depression scores significantly decreased after donation, but anxiety scores remained stable. Donors, who were mostly siblings, showed positive perceptions about donation, did not regret their decision, and strongly recommend it to others.

TÉCNICAS PARA AVALIAÇÃO IN VITRO DO EFEITO DE HERBICIDAS SOBRE BACILLUS THURINGIENSIS BERLINER VAR. KURSTAKI

RESUMO Objetivou-se comparar técnicas para a avaliação in vitro do efeito de herbicidas sobre Bacillus thuringiensis Berliner var. kurstaki (Btk). Foram testados os herbicidas sulfentrazone, lactofen, imazethapyr, fenoxaprop e metribuzin em duas concentrações, sobre células e esporos, em meio ágar nutriente sólido (MS) e caldo nutriente (CN) - líquido (ML), além da metabolização (MT) de tais produtos por Btk. Para células em MS, os herbicidas foram testados incorporados ao meio e em discos de papel-filtro impregnados nos produtos. Avaliou-se, respectivamente, as unidades formadoras de colônia por mililitro (UFC/mL) e a formação de halo de inibição. Para células, a mistura Btk + produtos + CN foi incubada em frascos erlemmeyer (30 ± 2° C, 150 rpm, 24h) e, em seguida, a mistura foi diluída e inoculada em MS, avaliando-se o número de UFC/mL. Os testes de MT e esporos foram realizados em líquido (água para MT e CN para esporos). O efeito dos produtos variou conforme a concentração utilizada, técnica de avaliação e a fase/estágio do microrganismo, sendo a técnica de avaliação em ML a mais indicada para a avaliação do efeito dos herbicidas sobre células de Btk, pois não apresenta limitações para difusão e permite quantificação. Os herbicidas, independentemente da concentração, foram incompatíveis para a célula, porém sulfetrazone e imazethapyr foram metabolizados por Btk. Todos herbicidas foram compatíveis com esporos, possibilitando a germinação, porém a concentração e tempo influenciaram nos resultados.