The appropriateness of ceftriaxone and metronidazole as empirical therapy in managing complicated intra-abdominal infection-experience from Western Health, Australia.

PURPOSE: This study aims to assess the microbiological profile, antimicrobial susceptibility and adequacy of intravenous ceftriaxone and metronidazole as empirical therapy for surgical patients presenting with complicated intra-abdominal infection. METHODS: This retrospective audit reviews the microbiological profile and sensitivity of intra-abdominal cultures from adult patients with complicated intra-abdominal infection who presented to the emergency department at Western Health (Melbourne, Australia) between November 2013 and June 2017. Using the hospital's database, an audit was completed using diagnosis related group (DRG) coded data. Ethics approval has been granted by the Western Health Human Research Ethics Committee. Results are stratified according to surgical conditions (appendicitis, cholecystitis, sigmoid diverticulitis and bowel perforation). The antimicrobial coverage of ceftriaxone and metronidazole is evaluated against these microbial profiles. RESULTS: A total of 1,412 patients were identified using DRG codes for intra-abdominal infection. All patients with microscopy and sensitivity results were included in the study. Patients without these results were excluded. 162 patients were evaluable. 180 microbiological cultures were performed through surgical intervention or radiologically guided aspiration of the intra-abdominal infection. Single or multiple pathogens were identified in 137 cultures. The most commonly identified pathogens were mixed anaerobes (12.6%), Escherichia coli (E. coli) (12.1%), mixed coliforms (11.6%) and Pseudomonas aeruginosa (7%). Other common pathogens (6% each) included Enterococcus faecalis, Streptococcus anginosus, Vancomycin-resistant Enterococci (VRE) and Extended Spectrum Beta-Lactamases (ESBL) producing E. coli. Organisms isolated in our study are consistent with existing literature. However, a significant proportion of antibiotic resistant organisms was identified in cases of perforated bowel and sigmoid diverticulitis. Broader spectrum antimicrobial therapy should therefore be considered in lieu of ceftriaxone and metronidazole in these cases. Ceftriaxone and metronidazole remain as appropriate empirical therapy for patients who presented with perforated appendicitis and cholecystitis. DISCUSSION: The empirical regime of ceftriaxone and metronidazole remains appropriate for intra-abdominal infection secondary to appendicitis and cholecystitis. In cases involving perforated small and large bowel, including complicated sigmoid diverticulitis, the judicious use of ceftriaxone and metronidazole is recommended.

A rare case of giant extra-ovarian mucinous cystadenoma arising from sigmoid mesocolon.

An 80-year-old female presented with one month history of acutely worsening abdominal distention and pain, without features of bowel obstruction. A giant intra-abdominal simple cyst, separate from the ovaries, was seen on imaging. Initial haematological and biochemical investigations, including tumour markers, were normal. At laparotomy, the cystic tumour was discovered to arise from the sigmoid mesocolon and was resected en bloc. Histopathology revealed the tumour to be a benign extra-ovarian mucinous cystadenoma, which is a neoplasm of ovarian origin that can arise from extra-ovarian sites, including the mesentery. Extra-ovarian mucinous cystadenoma arising specifically from the mesentery are very rare intra-abdominal neoplasms with malignant potential despite its benign appearance on investigations. This case aims to raise awareness of this condition and to highlight its diagnostic approach and surgical management.

Establishment and characterization of fetal and maternal mesenchymal stem/stromal cell lines from the human term placenta.

INTRODUCTION: Human placental mesenchymal stem/stromal cells (MSC) are an attractive source of MSC with great therapeutic potential. However, primary MSC are difficult to study in vitro due to their limited lifespan and patient-to-patient variation. METHODS: Fetal and maternal MSC were prepared from cells of the chorionic and basal plates of the placenta, respectively. Fetal and maternal MSC were transduced with the human telomerase reverse transcriptase (hTERT). Conventional stem cell assays assessed the MSC characteristics of the cell lines. Functional assays for cell proliferation, cell migration and ability to form colonies in soft agar were used to assess the whether transduced cells retained properties of primary MSC. RESULTS: Fetal chorionic and maternal MSC were successfully transduced with hTERT to create the cell lines CMSC29 and DMSC23 respectively. The lifespans of CMSC29 and DMSC23 were extended in cell culture. Both cell lines retained important MSC characteristics including cell surface marker expression and multipotent differentiation potential. Neither of the cell lines was tumourigenic in vitro. Gene expression differences were observed between CMSC29 and DMSC23 cells and their corresponding parent, primary MSC. Both cell lines show similar migration potential to their corresponding primary, parent MSC. DISCUSSION: The data show that transduced MSC retained important functional properties of the primary MSC. There were gene expression and functional differences between cell lines CMSC29 and DMSC23 that reflect their different tissue microenvironments of the parent, primary MSC. CMSC29 and DMSC23 cell lines could be useful tools for optimisation and functional studies of MSC.

A novel combination of homeobox genes is expressed in mesenchymal chorionic stem/stromal cells in first trimester and term pregnancies.

Human chorionic mesenchymal stem/stromal cells (CMSCs) derived from the placenta are similar to adult tissue-derived MSCs. The aim of this study was to investigate the role of these cells in normal placental development. Transcription factors, particularly members of the homeobox gene family, play crucial roles in maintaining stem cell proliferation and lineage specification in embryonic tissues. In adult tissues and organs, stem cells proliferate at low levels in their niche until they receive cues from the microenvironment to differentiate. The homeobox genes that are expressed in the CMSC niche in placental tissues have not been identified. We used the novel strategy of laser capture microdissection to isolate the stromal component of first trimester villi and excluded the cytotrophoblast and syncytiotrophoblast layers that comprise the outer layer of the chorionic villi. Microarray analysis was then used to screen for homeobox genes in the microdissected tissue. Candidate homeobox genes were selected for further RNA analysis. Immunohistochemistry of candidate genes in first trimester placental villous stromal tissue revealed homeobox genes Meis1, myeloid ectropic viral integration site 1 homolog 2 (MEIS2), H2.0-like Drosophila (HLX), transforming growth factor ß-induced factor (TGIF), and distal-less homeobox 5 (DLX5) were expressed in the vascular niche where CMSCs have been shown to reside. Expression of MEIS2, HLX, TGIF, and DLX5 was also detected in scattered stromal cells. Real-time polymerase chain reaction and immunocytochemistry verified expression of MEIS2, HLX, TGIF, and DLX5 homeobox genes in first trimester and term CMSCs. These data suggest a combination of regulatory homeobox genes is expressed in CMSCs from early placental development to term, which may be required for stem cell proliferation and differentiation.

Cardiopulmonary resuscitation with chest compressions during sustained inflations: a new technique of neonatal resuscitation that improves recovery and survival in a neonatal porcine model.

BACKGROUND: Guidelines on neonatal resuscitation recommend 90 chest compressions (CCs) and 30 manual inflations (3:1) per minute in newborns. The study aimed to determine whether CC s during sustained inflations (SIs) improves the recovery of asphyxiated newborn piglets in comparison with coordinated 3:1 resuscitation. METHODS AND RESULTS: Term newborn piglets (n=8/group) were anesthetized, intubated, instrumented, and exposed to 45-minute normocapnic hypoxia followed by asphyxia. Piglets were randomly assigned to receive either 3:1 resuscitation (3:1 group) or CCs during SIs (SI group) when the heart rate decreased to 25% of baseline. Piglets randomly assigned to the SI group received SIs with a pressure of 30 cm H2O for 30 s. During the SI, CCs at a rate of 120/min were provided. SI was interrupted after 30 s for 1 s before a further 30-s SI was provided. CCs were continued throughout SIs. CCs and SI were continued until the return of spontaneous circulation. Continuous respiratory parameters, cardiac output, mean systemic and pulmonary artery pressures, and regional blood flows were measured. Mean (standard deviation) time for return of spontaneous circulation was significantly reduced in SI group versus 3:1 group (32 [11] s versus 205 [113] s, respectively). In the SI group, administration of oxygen and epinephrine was significantly lower, whereas minute ventilation and exhaled CO2 were significantly increased. The SI group had significantly higher mean systemic and pulmonary arterial pressures during resuscitation in comparison with the 3:1 group (51 [10] versus 31 [5] mm Hg; 41[7] versus 31 [7] mm Hg, respectively; all P<0.05), with improved cardiac output and carotid blood flow. CONCLUSIONS: Combining CCs and SIs significantly improved the return of spontaneous circulation with better hemodynamic recovery in asphyxiated newborn piglets in comparison with standard coordinated 3:1 resuscitation.