Histopathology, mRNA expression profile, and donor-derived cell-free DNA for assessment of rejection in pediatric heart transplantation

BACKGROUND

The relationship between histopathologic and molecular ("MMDx"®) assessments of endomyocardial biopsy (EMB) and serum donor-derived cell-free DNA (ddcfDNA) in acute rejection (AR) assessment following pediatric heart transplantation (HT) is unknown.

METHODS

EMB sent for MMDx and histopathology from November 2021 to September 2022 were reviewed. MMDx and histopathology results were compared. DdcfDNA obtained ≤1 week prior to EMB were compared with histopathology and MMDx results. The discrimination of ddcfDNA for AR was assessed using receiver-operating curves.

FINDINGS

In this study, 177 EMBs were obtained for histopathology and MMDx, 101 had time-matched ddcfDNA values. MMDx and Histopathology displayed moderate agreement for T-cell-mediated rejection (TCMR, Kappa = 0.52, p < .001) and antibody-mediated rejection (ABMR, Kappa = 0.41, p < .001). Discordant results occurred in 24% of cases, most often with ABMR. Compared with no AR, ddcfDNA values were elevated in cases of AR diagnosed by both histopathology and MMDx (p < .01 for all). Additionally, ddcfDNA values were elevated in injury patterns on MMDx, even when AR was not present (p = .01). DdcfDNA displayed excellent discrimination (AUC 0.83) for AR by MMDx and/or histopathology. Using a threshold of ≥0.135%, ddcfDNA had a sensitivity of 90%, specificity of 63%, PPV of 52%, and NPV of 94%.

CONCLUSIONS

Histopathology and MMDx displayed moderate agreement in diagnosing AR following pediatric HT, with most discrepancies noted in the presence of ABMR. DdcfDNA is elevated with AR, with excellent discrimination and high NPV particularly when utilizing MMDx. A combination of all three tests may be necessary in some cases.

Evaluation of Sponge Wipe Surface Sampling for Collection of Potential Surrogates for Non-spore-forming Bioterrorism Agents

AIM

Evaluate the efficacy of sponge wipe sampling at recovering potential bacterial surrogates for Category A and B non-spore-forming bacterial bioterrorism agents from hard nonporous surfaces.

METHODS

A literature survey identified seven nonpathogenic bacteria as potential surrogates for selected Category A and B non-spore-forming bacterial agents. Small (2- by 4-cm) and large (35.6- by 35.6-cm) coupons made from either stainless steel, plastic, or glass, were inoculated and utilized to assess persistence, and surface sampling efficiency, respectively. Three commercially available premoistened sponge wipes (3M™, Sani-Stick®, and Solar-Cult®) were evaluated.

RESULTS

Mean recoveries from persistence testing indicated that three microorganisms (Yersinia ruckeri, Escherichia coli, and Serratia marcescens) demonstrated sufficient persistence across all tested material types. Sampling of large inoculated (≥ 107 CFU per sample) coupons resulted in mean recoveries ranging from 6.6 to 3.4 Log10 CFU per sample. Mean recoveries for the Solar-Cult®, 3M™ sponge wipes, and Sani-Sticks® across all test organisms and all material types were ≥ 5.7, ≥ 3.7, and ≥ 3.4 Log10 CFU per sample, respectively. Mean recoveries for glass, stainless steel, and ABS plastic across all test organisms and all sponge types were ≥ 3.8, ≥ 3.7, and ≥ 3.4 Log10 CFU per sample, respectively.

CONCLUSIONS

Recovery results suggest that sponge wipe sampling can effectively be used to recover non-spore-forming bacterial cells from hard, nonporous surfaces such as stainless steel, ABS plastic, and glass.

Tricuspid Atresia with Absent Pulmonary Valve with Nearly Discontinuous Branch Pulmonary Arteries

Absent pulmonary valve with tricuspid atresia or tricuspid stenosis (APV-TA/TS) is an extremely rare congenital heart defect associated with significant morbidity and mortality. Compared to Tetralogy of Fallot with Absent Pulmonary Valve Syndrome, branch pulmonary arteries are not typically significantly dilated. We present the case of a newborn male prenatally diagnosed APV-TA with intact ventricular septum (IVS) and nearly discontinuous branch pulmonary arteries, the surgical strategy employed, and the salient hemodynamic factors considered in the medical decision-making.

Modifying the trajectory of epicardial leads can substantially reduce MRI-induced RF heating in pediatric patients with a cardiac implantable electronic device at 1.5T

PURPOSE

After epicardial cardiac implantable electronic devices are implanted in pediatric patients, they become ineligible to receive MRI exams due to an elevated risk of RF heating. We investigated whether simple modifications in the trajectories of epicardial leads could substantially and reliably reduce RF heating during MRI at 1.5 T, with benefits extending to abandoned leads.

METHODS

Electromagnetic simulations were performed to assess RF heating of two common 35-cm epicardial lead trajectories exhibiting different degrees of coupling with MRI incident electric fields. Experiments in anthropomorphic phantoms implanted with commercial cardiac implantable electronic devices confirmed the findings. Both electromagnetic simulations and experimental measurements were performed using head-first and feet-first positioning and various landmarks. Transfer function approach was used to assess the performance of suggested modifications in realistic body models.

RESULTS

Simulations (head-first, chest landmark) of a 35-cm epicardial lead with a trajectory where the excess length of the lead was looped and placed on the inferior surface of the heart showed an 87-fold reduction in the 0.1 g-averaged specific absorption rate compared with the lead where the excess length was looped on the anterior surface. Repeated experiments with a commercial epicardial device confirmed this. For fully implanted systems following low-specific absorption rate trajectories, there was a 16-fold reduction in the average temperature rise and a 28-fold reduction for abandoned leads. The transfer function method predicted a 7-fold reduction in the RF heating in 336 realistic scenarios.

CONCLUSION

Surgical modification of epicardial lead trajectory can substantially reduce RF heating at 1.5 T, with benefits extending to abandoned leads.

Donor-specific antibodies after heart transplantation for Fontan-associated protein-losing enteropathy

BACKGROUND

Despite ubiquitous exposure to sensitizing events, most Fontan PLE patients have low panel reactive antibodies (PRA). To assess whether they are at risk for donor-specific antibody (DSA) memory response following heart transplantation (HT) when their PLE resolves, DSA profiles, incidence of rejection, and graft outcomes in Fontan recipients with and without PLE were compared.

METHODS

Patient characteristics, appearance of newly detected DSA (nDSA), and graft outcomes were compared between patients with and without PLE using Wilcoxon rank-sum and Chi-squared tests. DSA burden was quantified using titers and time to nDSA, incidence of rejection, and graft outcomes were compared using Kaplan-Meier curves and the log-rank test.

RESULTS

Characteristics of patients with and without PLE were similar. Lymphocyte and albumin levels were lower in the PLE group, and flow PRA were comparable. Graft failure, CAV, and ACR were similar between the two groups, but AMR occurred more frequently in the PLE group (p = .03). Nearly 50% of PLE patients experienced class II nDSA by 1-year post-HT, compared to 30% of non-PLE patients, but this difference was statistically not significant. Antibody burden did not differ between groups.

CONCLUSIONS

In this cohort, PLE was associated with AMR within the first-year post-HT, despite no significant difference in nDSA. Small patient numbers limited statistical comparison of nDSA in this cohort. PLE may be a risk factor for AMR post-HT, and the possibility of a clinically important DSA memory response remains. Larger studies are necessary to better understand these preliminary findings.

Biventricular Assist Device Support for Intractable Arrhythmias From Histiocytoid Cardiomyopathy

Histiocytoid cardiomyopathy (HICMP) is a rare mitochondrial cardiomyopathy associated with recurrent life-threatening arrhythmias and variable degrees of systolic dysfunction. Successful heart transplantation for HICMP has been described, but there has been no published experience with biventricular assist device (BiVAD) support for intractable arrhythmias in HICMP. We report a 13 month old girl with left ventricular noncompaction and preserved systolic function who presented in cardiogenic shock secondary to incessant ventricular arrhythmias. After failed attempts at chemical and electrical cardioversion, she underwent BiVAD implantation as bridge to transplantation. Her BiVAD course was complicated by mechanical inflow obstruction during sinus rhythm, necessitating left-sided cannulation revision from an apical to atrial inflow cannula. This maneuver resolved the obstruction and the patient was transitioned to Berlin EXCOR (Berlin Heart Inc, The Woodlands, TX) BiVADs. On Berlin pumps, she had intermittent pauses (no fill/no eject) while in sinus rhythm, felt to be due to competition from intrinsic ejection. Despite these pauses, the patient experienced an uneventful remainder of her BiVAD course (205 days total) with minimal fibrin deposition and no device-related complications. BiVAD can support pediatric patients with hemodynamically significant arrhythmias to transplantation. Atrial cannulation strategy may be preferred in cases of preserved systolic function, ventricular noncompaction, and frequent rhythm changes.

Evaluating the impact of ultraviolet C exposure conditions on coliphage MS2 inactivation on surfaces

The COVID-19 pandemic has raised interest in using devices that generate ultraviolet C (UVC) radiation as an alternative approach for reducing or eliminating microorganisms on surfaces. Studies investigating the efficacy of UVC radiation against pathogens use a wide range of laboratory methods and experimental conditions that can make cross-comparison of results and extrapolation of findings to real-world settings difficult. Here, we use three different UVC-generating sources - a broad-spectrum pulsed xenon light, a continuous light-emitting diode (LED), and a low-pressure mercury vapour lamp - to evaluate the impact of different experimental conditions on UVC efficacy against the coliphage MS2 on surfaces. We find that a nonlinear dose-response relationship exists for all three light sources, meaning that linear extrapolation of doses resulting in a 1-log10 (90%) reduction does not accurately predict the dose required for higher (e.g. 3-log10 or 99.9%) log10 reductions. In addition, our results show that the inoculum characteristics and underlying substrate play an important role in determining UVC efficacy. Variations in microscopic surface topography may shield MS2 from UVC radiation to different degrees, which impacts UVC device efficacy. These findings are important to consider in comparing results from different UVC studies and in estimating device performance in field conditions.

HeartMate 3 VAD in a single-ventricle patient palliated with a superior-cavopulmonary anastomosis

We report a 9-year-old, 25 kilograms child with failing single-ventricle palliation with a superior-cavopulmonary anastomosis successfully supported with a HeartMate 3™ ventricular assist device as a bridge-to-transplant.

Inactivation of MS2 bacteriophage on copper film deployed in high touch areas of a public transport system

Although SARS-CoV-2 is primarily an airborne risk, the COVID-19 pandemic also highlighted the need for self-disinfection surfaces that could withstand the demand of high occupant densities characteristic of public transportation systems. The aim of this study was to evaluate the durability and antiviral activity of a copper film deployed for 90 days in two high touch locations within an active metropolitan bus and railcar. The antiviral efficacy of this copper film after being deployed in transit vehicles for 90 days (deployed copper film) was then compared to new (unused) copper film to determine if frequent touches and cleaning protocols could decrease the efficacy of the copper films. Deployed copper film, new copper film, and aluminium foil (positive control) coupons were inoculated with ~1 × 10⁶ MS2 virus particles, allowed a contact time of either 5- or 10-min, and analysed for residual viral infectiousness. On both new and deployed copper films, MS2 was completely inactivated (≥5 log reduction) at both time points. These results suggest that the copper film may provide the durability demanded by high touch public spaces while maintaining the antiviral activity necessary to reduce exposure risk and viral transmission via surfaces in public transportation settings.

Successful outcome following resection of metachronous pancreatic metastasis from a rhabdomyosarcoma

BACKGROUND

Pancreatic metastases (PM) are rare, comprising 3% of pancreatic tumours removed in sizable series of operations. This report presents the first case of metachronous pancreatic metastases from rhabdomyosarcoma successfully treated by pancreaticoduodenectomy.

CASE REPORT

A 19-year old man was admitted with a tumor in the head of the pancreas, 1 year after undergoing removal of an alveolar RMS from the right hand. . Computed tomography (CT) scan demonstrates a solitary hypodence tumour of the pancreas. The patient underwent a pancreaticoduodenectomy and the postoperative course was uneventful. Pathologic examination confirmed the metastatic alveolar RMS without lymph node involvement. At most recent follow-up, 36 months after pancreaticoduodenectomy, the patient has no evidence of disease.

CONCLUSION

Although rare, rhabdomyosarcoma can metastasize to the pancreas. The surgeons must be aware of this complication, and that such pancreatic metastases are potentially resectable with a good long term outcome.

Réponse à la vaccination contre le SARS-CoV-2 chez des patients hémodialysés chroniques

Introduction

Les patients hémodialysés chroniques (HDC) sont à haut risque de développer une forme grave d’infection à SARS-CoV-2. Ils constituent une population cible pour la vaccination. Toutefois, la réponse vaccinale chez ces patients n’est pas connue.

Matériels et méthodes

Étude observationnelle monocentrique portant sur l’ensemble des patients HDC à qui la vaccination contre la COVID-19 par le vaccin à ARNm BNT162b2 (Pfizer–BioNTech®) a été proposée. Deux injections ont été réalisées à 28 j d’intervalle, dans le bras opposé à l’abord vasculaire. Les données cliniques ont été recueillies prospectivement. La recherche d’anticorps spécifiques (IgG et IgM anti-protéine Spike) a été réalisée par immunochromatographie (COVID-19 BSS, Biosynex®) sur des sérums collectés avant la première injection, puis avant la seconde et 1 mois après. Les résultats sont exprimés en médiane [IQR : 25–75] ou %.

Résultats

Entre le 15 janvier et le 21 mars 2021, la vaccination a été proposée aux 55 patients du centre et acceptée par 49 (89,1 %) patients, les 6 autres ayant refusé. Parmi les 49 patients vaccinés, l’âge médian est de 70 [63–82,5] ans, 17 (34,7 %) sont diabétiques, et 8 (16,3 %) ont une greffe d’organe solide. La durée médiane en dialyse à la vaccination est de 26,2 [17,8–49,9] mois ; les patients sont dialysés sur une membrane en polysulfone (PSF), sauf 4 (8,2 %) sur une membrane en polyméthylmétacrylate (PMMA).

La séroprévalence en IgG à j0 est de 12,2 % (6/49 patients, dont 4 ayant un antécédent de COVID symptomatique de plus de 3 mois, avec PCR positive). Parmi les 43 patients séronégatifs à l’inclusion, 10 sont encore en cours de vaccination. Les 33 patients ayant complété le schéma vaccinal ont les résultats suivants, respectivement avant la seconde injection et 1 mois après : IgM, 9,1 % (3 patients) et 12,1 % (4 patients) ; IgG, 9,1 % (3 patients) et 87,9 % (29 patients).

Tous les patients positifs en IgM le sont également en IgG (aucun n’a développé de signes cliniques évocateurs de COVID-19 dans le suivi). Parmi les 4 patients non répondeurs, 1 recevait une immunothérapie pour cancer cutané, et tous ont une membrane en PSF. Tous les patients transplantés d’organe ont eu une réponse vaccinale positive 1 mois après la seconde injection. Le profil sérologique des patients dialysés avec un filtre en PMMA est comparable à ceux avec un filtre en PSF. La tolérance est bonne: 1 patiente a présenté une réponse systémique avec fièvre et frisson, et 60,1 % ont eu une réaction douloureuse au point d’injection ayant duré 24 h.

Conclusion

L’acceptation et la réponse vaccinale au vaccin à ARNm contre la COVID-19 sont bonnes chez les patients HDC.

Clinic Versus Ambulatory Blood Pressure in Resistant Hypertension: Impact of Antihypertensive Medication Nonadherence

Clinic-ambulatory blood pressure (BP) difference is influenced by patients- and device-related factors and inadequate clinic-BP measurement. We investigated whether nonadherence to antihypertensive medications may also influence this difference in a post hoc analysis of the DENERHTN trial (Renal Denervation for Hypertension). We pooled the data of 77 out of 106 evaluable patients with apparent resistant hypertension who received a standardized antihypertensive treatment and had both ambulatory BP and drug-screening results available at baseline after 1 month of standardized triple therapy and at 6 months on a median of 5 antihypertensive drugs. After drug assay samplings on study visits, patients took their antihypertensive treatment under supervision immediately after the start of the ambulatory BP recording, and supine clinic BP was measured 24 hours post-dosing; both allowed to calculate the clinic minus daytime ambulatory systolic BP (SBP) difference (clinic-SBP–day-SBP). A total of 29 (37.7%) were found nonadherent to medications at baseline and 38 (49.4%) at 6 months. At baseline, the mean clinic-SBP–day-SBP difference in the nonadherent group was 12.7 mm Hg (95% CI, 7.8–17.7 mm Hg, P <0.001). In contrast, clinic SBP was almost identical to day-SBP in the adherent group (clinic-SBP–day-SBP difference, 0.1 mm Hg; 95% CI, −3.3 to 3.5 mm Hg; P =0.947). Similar observations were made at 6 months. Using receiver operating characteristics curves, we found that a 6 mm Hg cutoff of clinic-SBP–day-SBP difference had 67% sensitivity and 69% specificity to predict nonadherence to the triple therapy at baseline. In conclusion, a large clinic-SBP–day-SBP difference may help discriminating between adherence and nonadherence to treatment in patients with resistant hypertension.

Clinical Trial Registration—

URL: https://www.clinicaltrials.gov . Unique identifier: NCT01570777.

A proteomic analysis of the statocyst endolymph in common cuttlefish (Sepia officinalis): an assessment of acoustic trauma after exposure to sound

Recent studies, both in laboratory and sea conditions, have demonstrated damage after sound exposure in the cephalopod statocyst sensory epithelium, which secretes endolymph protein. Here, the proteomic analysis of the endolymph was performed before and after sound exposure to assess the effects of exposure to low intensity, low frequency sounds on the statocyst endolymph of the Mediterranean common cuttlefish (Sepia officinalis), determining changes in the protein composition of the statocyst endolymph immediately and 24 h after sound exposure. Significant differences in protein expression were observed, especially 24 h after exposure. A total of 37 spots were significantly different in exposed specimens, 17 of which were mostly related to stress and cytoskeletal structure. Among the stress proteins eight spots corresponding to eight hemocyanin isoforms were under-expressed possible due to lower oxygen consumption. In addition, cytoskeletal proteins such as tubulin alpha chain and intermediate filament protein were also down-regulated after exposure. Thus, endolymph analysis in the context of acoustic stress allowed us to establish the effects at the proteome level and identify the proteins that are particularly sensitive to this type of trauma.

Bridge to Transplantation With Long-Term Mechanical Assist Devices in Adults With Transposition of the Great Arteries

Prior to the widespread adoption of the arterial switch operation, patients with transposition of the great arteries (TGA) commonly underwent atrial switch operation (Mustard or Senning). It is not uncommon for these patients to progress to end stage heart failure and increasingly ventricular assist devices (VADs) are used to support these patients as a bridge to transplantation, though there is limited experience with this worldwide. A retrospective review of our institution's VAD database was undertaken and revealed seven adult patients with a history of TGA and subsequent systemic ventricular failure were implanted with a VAD: four of whom received the VAD as a bridge to transplantation (BTT) at the time of implantation, two who were initially designated as destination therapy secondary to severe pulmonary hypertension, and one who was designated as destination therapy secondary to a high risk of life-threatening non-compliance. Seven patient cases who received a VAD for severe systemic ventricular failure were included in this study. The mean age of the patients was 40 years and the majority of patients were male (6/7, 85%). Five of the patients (71.4%) had previously undergone an atrial switch operation and all of these were Mustard procedures. Two of the seven patients (28.5%) had congenitally corrected transposition of the great arteries (CC-TGA). Two of the seven patients (28.5%) had supra-systemic pulmonary pressures before VAD implantation and were designated as destination therapy (DT). One of these patients was later designated as BTT as an improvement in his pulmonary vascular resistance was observed, and subsequently underwent heart transplantation. Because of anatomic considerations, four of the patients (57%) underwent redo-sternotomy with outflow cannula anastomosis to the ascending aorta, one patient underwent VAD implantation via a left subcostal incision with anastomosis of the outflow graft to the descending thoracic aorta, and two patients (28.5%) underwent VAD implantation via a left thoracotomy and anastomosis of the outflow cannula to the descending thoracic aorta. Six of the seven patients had a HeartWare HVAD VAD implanted; one received a Thoratec Heartmate II VAD. Two patients underwent VAD explant and orthotopic heart transplant, 222 days and 444 days after VAD implant, respectively. One patient died on postoperative day 17 after complications from recurrent VAD thrombosis despite multiple pump exchanges. Four patients remain on VAD support, three of these patients are awaiting transplantation at last follow-up (mean days on support, 513 days). Bridge to transplantation with a durable VAD is technically feasible and relatively safe in patients with TGA. Multiple redo-sternotomies can be avoided with a left posterior thoracotomy approach and outflow graft anastomosis to the descending thoracic aorta after careful anatomic considerations.

Sternal Precautions After Pediatric Cardiac Surgery: A Survey of Current Practice

Date Presented 4/9/2016

Sternal precautions (SPs) are variable among pediatric heart centers surveyed. Results indicate institutions determine SP protocol based on culture and preferences rather than evidence-based research. Prolonged physical restrictions may negatively affect motor and sensory development.

Primary Author and Speaker: Leslie Rodman Uher

Additional Author and Speaker: Nguyenvu Nguyen

Contributing Author: Michael Monge

Protein expression parallels thermal tolerance and ecologic changes in the diversification of a diving beetle species complex

Physiological changes associated with evolutionary and ecological processes such as diversification, range expansion or speciation are still incompletely understood, especially for non-model species. Here we study differences in protein expression in response to temperature in a western Mediterranean diving beetle species complex, using two-dimensional differential gel electrophoresis with one Moroccan and one Iberian population each of Agabus ramblae and Agabus brunneus. We identified proteins with significant expression differences after thermal treatments comparing them with a reference EST library generated from one of the species of the complex (A. ramblae). The colonisation during the Middle Pleistocene of the Iberian peninsula by A. ramblae, where maximum temperatures and seasonality are lower than in the ancestral north African range, was associated with changes in the response to 27 °C in proteins related to energy metabolism. The subsequent speciation of A. brunneus from within populations of Iberian A. ramblae was associated with changes in the expression of several stress-related proteins (mostly chaperons) when exposed to 4 °C. These changes are in agreement with the known tolerance to lower temperatures of A. brunneus, which occupies a larger geographical area with a wider range of climatic conditions. In both cases, protein expression changes paralleled the evolution of thermal tolerance and the climatic conditions experienced by the species. However, although the colonisation of the Iberian peninsula did not result in morphological change, the speciation process of A. brunneus within Iberia involved genetic isolation and substantial differences in male genitalia and body size and shape.

ETV5 cooperates with LPP as a sensor of extracellular signals and promotes EMT in endometrial carcinomas

Endometrial carcinoma (EC) is the most frequent among infiltrating tumors of the female genital tract, with myometrial invasion representing an increase in the rate of recurrences and a decrease in survival. We have previously described ETV5 transcription factor associated with myometrial infiltration in human ECs. In this work, we further investigated ETV5 orchestrating downstream effects to confer the tumor the invasive capabilities needed to disseminate in the early stages of EC dissemination. Molecular profiling evidenced ETV5 having a direct role on epithelial-to-mesenchymal transition (EMT). In particular, ETV5 modulated Zeb1 expression and E-Cadherin repression leading to a complete reorganization of cell-cell and cell-substrate contacts. ETV5-promoted EMT resulted in the acquisition of migratory and invasive capabilities in endometrial cell lines. Furthermore, we identified the lipoma-preferred partner protein as a regulatory partner of ETV5, acting as a sensor for extracellular signals promoting tumor invasion. All together, we propose ETV5-transcriptional regulation of the EMT process through a crosstalk with the tumor surrounding microenvironment, as a principal event initiating EC invasion.

Measurement uncertainty of 25-OH vitamin D determination with different commercially available kits: impact on the clinical cut offs

SUMMARY

Due to "measurement uncertainty", the "true" 25-OH vitamin D (25(OH)D) of a patient (whatever the commercially available assay tested) will be >80 nmol/L if its measured concentration is >100 nmol/L. Thus, if a physician considers that a normal VTD status is a 25(OH)D level >or=80 nmol/L, he should ensure that the patient's results are >or=100 nmol/L.

INTRODUCTION

Many experts recommend that serum levels of 25(OH)D should be above a lower normal limit of 75-80 nmol/L. However, the value delivered by laboratories is only an estimation of the "true" value due to "measurement uncertainty." When using a cut off, measurement uncertainty around the cut off is important because therapeutic actions may differ if the measured value is below or above the limit. We aimed to establish the "measurement uncertainty" at different levels of concentration for several commercially available 25(OH)D analytical techniques.

METHODS

We constituted three pools of serum with different 25(OH)D concentrations. Each pool was assayed in triplicate during 5 days with the DiaSorin RIA, Liaison, Elecsys, and Chromsystems-HPLC assays.

RESULTS

We report a relatively high "measurement uncertainty" for the measurement of 25(OH)D for the four different techniques: the mean relative uncertainties, all techniques confounded were 19.4%, 16.0%, and 11.3% for pool 1 (35.3 nmol/L), pool 2 (79.5 nmol/L), and pool 3 (126.1 nmol/L), respectively.

CONCLUSIONS

Our results show that, whatever the assay, the "true" 25(OH)D of a patient will be >80 nmol/L if its measured concentration is >100 nmol/L. In other words, if a physician considers that a normal VTD status is defined by a 25(OH)D level >or=80 nmol/L, he should ensure that the patients present a 25(OH)D >or=100 nmol/L.

Novel molecular profiles of endometrial cancer-new light through old windows

Endometrial carcinoma (EC) is the most common gynecological malignancy in the western world. A widely accepted dualistic model, which has been established on a morphological basis, differentiates EC into two broad categories: Type I oestrogen-dependent adenocarcinoma with an endometrioid morphology and Type II non-oestrogen-dependent EC with a serous papillary or clear cell morphology. Molecular genetic evidence indicates that endometrial carcinoma, as described in other malignancies, likely develops as the result of a stepwise accumulation of alterations in cellular regulatory pathways, such as oncogene activation and tumor suppressor gene inactivation, which lead to dysfunctional cell growth. These molecular alterations appear to be specific in Type I and Type II cancers. In type I endometrioid endometrial cancer, PTEN gene silencing in conjunction with defects in DNA mismatch repair genes, as evidenced by the microsatellite instability phenotype, or mutations in the K-ras and/or beta-catenin genes, are recognized major alterations, which define the progression of the normal endometrium to hyperplasia, to endometrial intraepithelial neoplasia, and then on to carcinoma. In contrast, Type II cancers show mutations of TP53 and Her-2/neu and seem to arise from a background of atrophic endometrium. Nevertheless, despite the great effort made to establish a molecularly-based histological classification, the following issues must still be clarified: what triggers the tumor cells to invade the myometrium and what causes vascular or lymphatic dissemination, finally culminating in metastasis? RUNX1, a transcription factor, was recently identified as one of the most highly over-expressed genes in a microarray study of invasive endometrial carcinoma. Another candidate gene, which may be associated with an initial switch to myometrial infiltration, is the transcription factor ETV5/ERM. These studies, as well as those conducted for other genes possibly involved in the mitotic checkpoint as a major mechanism of carcinogenesis in non-endometrioid endometrial cancer, could help in understanding the differences in the biology and the clinical outcome among histological types.

Molecular determinants of invasion in endometrial cancer

Endometrial carcinoma is the most common gynaecological malignancy in the western world and the most frequent among infiltrating tumours of the female genital tract. Despite the characterisation of molecular events associated with the development of endometrial carcinoma, those associated with the early steps of infiltration and invasion in endometrial cancer are less known. Deep myometrial invasion correlates with more undifferentiated tumours, lymph-vascular invasion, node affectation and decreased global survival. In this review we present an overview of the molecular pathology of myometrial infiltration that defines the initial steps of invasion in endometrial cancer. Down-regulation of E-cadherin as a main player of epithelial to mesenchymal transition, as well as modifications on other molecules involved in cell-cell contacts, render cells with a migratory phenotype. In addition, altered signalling pathways and transcription factors associate with myometrial invasion, histologic grade and metastasis.

Retroperitoneal hematoma compressing a single functioning kidney: an unusual cause of obstructive renal failure

We report a case of a retroperitoneal hematoma occurring in a patient under anticoagulation therapy for deep-venous thrombosis and presenting as an anuric acute renal failure. A coexisting polycythemia vera led to misdiagnosis that could have been life-threatening. A woman, known for polycythemia vera and a single functioning right kidney, was admitted with mild abdominal pain in a context of recent deep venous thrombosis under low-molecular weight heparin. Clinical examination revealed hepatomegaly associated with polycythemia vera. Biochemical evaluation disclosed an acute renal failure, and renal ultrasonography showed no dilation of the renal pelvis. Retroperitoneal hematoma resulted in shock, progressive anemia and obstructive renal failure, related to renal pelvic compression. A right renal indwelling catheter was introduced to restore urine flow after one hemodialysis session, and an inferior vena cava filter was placed because of anti-coagulation contra-indication. However, pulmonary embolism occurred, so that oral anticoagulants were introduced. The hematoma resorbed spontaneously, and a year after this episode, the patient is still alive and well. Retroperitoneal hematoma is a rare cause of obstructive acute renal failure and a life-threatening complication of anti-coagulation therapy.

Hostility and helper T-cells in patients with bulimia nervosa

OBJECTIVE

The study aimed to analyze the correlation between lymphocyte counts and several psychopathological variables associated with psychological instability (depression, hostility, impulsivity, self-defeating personality traits, and borderline personality symptoms) in patients with bulimia nervosa (BN).

METHOD

Sixty BN patients were assessed, using specific scales for eating pathology, general psychopathology, impulsivity, depression, and borderline personality features. Lymphocyte and lymphocyte subset counts were performed. Plasma cortisol at 8:00, before and after administration of 1 mg of dexamethasone at 23:00, was determined. The influence of body weight, and the use of tobacco, alcohol, and caffeine was controlled. The relationship between each isolated variable and the number of immune cells was analyzed. In a second step, supplementary post-hoc analysis of the variables was introduced to confirm the accuracy of the psychopathological assessment.

RESULTS

Hostility was negatively correlated with the number of helper T-cells (CD4+). Patients with high hostility had lower CD4+ cell counts and lower CD4+/CD8+ ratios. In the post-hoc control study, hostility was significantly related with other "interpersonal" items.

CONCLUSIONS

These results support the idea that hostility, as an expression of disturbed interpersonal relationships, could play a role as a modulator of immune activity in patients with BN.

Inter-method variability in PTH measurement: implication for the care of CKD patients

The National Kidney Foundation/Kidney-Dialysis Outcome Quality Initiative guidelines recommend to maintain the serum intact parathyroid hormone (PTH) concentration between 150 and 300 ng/l in chronic kidney disease (CKD) stage 5 patients. As these limits were derived from studies that used the Allegro intact PTH assay, we aimed to evaluate whether they were applicable to other PTH assays. We compared the PTH concentrations measured with 15 commercial immunoassays in 47 serum pools from dialysis patients, using the Allegro intact PTH assay as the reference. We also evaluated the recovery of graded amounts of synthetic 1-84 and 7-84 PTH added separately to a serum pool. Although the assays were highly correlated, the concentrations differed from one assay to another. The median bias between the tested assays and the Allegro intact PTH assay ranged from -44.9 to 123.0%. When the PTH concentrations were 150 or 300 ng/l with the Allegro intact PTH assay, they ranged with other assays from 83 to 323 ng/l and from 160 to 638 ng/l, respectively. The tested assays recognized 7-84 PTH with various cross-reactivities, whereas a given amount of 1-84 PTH was recovered differently by these assays. We found important inter-method variability in PTH results owing to both antibody specificity and standardization reasons. The unacceptable consequence is that opposite therapeutic attitudes may be reached in a single patient depending on the PTH assay used. We propose to use assay-specific decision limits for CKD patients, or to apply a correcting factor to the PTH results obtained with a given assay.

Molecular pathology of endometrial carcinoma: transcriptional signature in endometrioid tumors

A dualistic model, which has been established on a morphological basis and that differentiates type I endometrioid from type II non-endometrioid endometrial cancer, is widely accepted. Molecular genetics have provided us with data supporting the dualistic model of endometrial tumorigenesis and with some clues to speculate about the sequence of the molecular alterations defining the tumorigenesis pathways. In type I endometrioid endometrial cancer, PTEN gene silencing, microsatellite instability associated with defects in DNA mismatch repair genes, or mutations in the K-ras gene are the known major alterations defining the progression from normal endometrium to hyperplasia and then on to carcinoma. Recently, cDNA microarray technology for identifying the differences in gene expression patterns between the histological types of endometrial cancer have permitted the identification of differentially expressed genes that could help us to understand differences in the biology and the clinical outcome between histiotypes. Genes involved in the mitotic checkpoint as a major mechanism of carcinogenesis in non-endometrioid endometrial cancer, or altered genes associated with the initial steps of myometrial infiltration in endometrioid endometrial cancer, represent examples of how useful large genetic screenings can be for understanding the tumorigenesis process and the future directions in the molecular pathogenesis of endometrial cancer.

[Study of the renal acidification capacity in children diagnosed of idiopathic hypercalciuria]

OBJECTIVE

To study the capacity of renal acidification in a group of children diagnosed of idiopathic hypercalciuria.

PATIENT AND METHODS

36 children were studied, to those that were determined the pCO2 (UpCO2) maximum urinary with two different stimuli, acetazolamide and sodium bicarbonate (NaHCO3). At 33 of them, was performed an acidification test with frusemide stimulus. We studied a control group of 13 healthy children so much for the first one as the second tests and other 14 healthy children for the acidification test with frusemide.

RESULTS

In the tests performed with NaHCO3 and acetazolamide stimulus, they were not proven differences in the values of UpCO2 neither in the urinary concentration of HCO3- (UHCO3-) than control children. Nevertheless, the UpCO2 and the concentration of UHCO3- in the patients were significantly lower with acetazolamide with regard to the NaHCO3 stimulus. In the acidification test with frusemide, significantly lower values of titratable acid and ammonium were obtained than control children.

CONCLUSIONS

In children with idiopathic hypercalciuria, the capacity of secretion of H+ is normal, what is evidenced, especially, when studying the maximum UpCO2 after stimulus with NaHCO3. When diuretics are used as stimuli, exists more negative results that can be due to a certain partial resistance to the action of the same ones or to that are less potent to induce the secretion of H+.

[Purging behaviors and nutritional status in anorexia nervosa and bulimia nervosa]

AIMS

The aim of the study was to investigate whether the use of purgative methods in patients with eating disorders (anorexia nervosa [AN] and bulimia nervosa [BN]) could be capable of producing changes in the nutritional status of the patients.

SETTING AND PATIENTS

The group under study was composed of 184 female eating disordered outpatients. One hundred and sixteen patients (63.0%) fulfilled the DSM-IV diagnostic criteria for BN (90 purging type, 26 nonpurging type). Sixty eight patients (37.0%) fulfilled the DSM-IV criteria for the diagnosis of AN (48 restricting type, 20 binging-purging type).

METHODS

The assessment process included anthropometry (body circumferences and skinfold thickness) and body impedance analysis.

RESULTS

The two subgroups of AN patients significantly differed from each of the BN subgroups. From a nutritional point of view, some significant differences between the two DSM-IV subtypes of AN existed, but not between the purging type and the nonpurging type of BN.

CONCLUSIONS

The paper discusses the clinical significance of these findings. An alternative subtypification of AN patients is proposed: 1) restricting type [patients who control their food intake and do not purge]; 2) purging type [patient with true episodes of binging which are followed by purgative behaviors]; and 3) pseudopurging type [patients with subjective binging episodes who use purging methods].