Present and past perspectives on Clostridium difficile infection. / Perspectivas históricas y vigentes sobre la infección por Clostridium difficile.

Clostridium difficile is a Gram-positive bacillus that has become one of the main hospital-acquired human gastrointestinal infections in recent years. Its incidence is on the rise, involving more virulent strains, affecting new and previously uncontemplated groups of patients, and producing changes in clinical presentation and treatment response that influence disease outcome. Early diagnosis and disease stratification based on the severity of C.difficile infection are essential for therapeutic management and the implementation of containment measures. However, the speed at which new strains with greater pathogenicity are developing is surpassing that of the development of new drugs, making it necessary to validate other therapeutic options. The present article is a review of the epidemiologic, pathophysiologic, diagnostic, and therapeutic aspects of C.difficile infection, from its first isolation to the present date, that aims to contribute to the preparation of general physicians and specialists, so that patients with this infection receive opportune and quality medical attention.

Factors influencing radiation exposure during internal fixation of hip fractures.

The use of fluoroscopy is of great importance for operative fixation of fractures. Previous studies have shown an increased fluoroscopy time for intramedullary nails and with junior surgeons in comparison with more experienced surgeons. We examined the impact of operation length on fluoroscopy dose, cumulative fluoroscopy time between consultant and registrar surgeons and cumulative fluoroscopy time between dynamic hip screw and intramedullary nailing. We performed a retrospective cohort study of all patients admitted to our centre over the period of 1 year. Patients who underwent dynamic hip screw (DHS) or intramedullary (IM) nailing were identified from our in-hospital hip fracture database. Intraoperative fluoroscopy images were then accessed through our hospital's medical imaging software. A total of 137 patients were identified. Fluoroscopy reports were not available for 49 patients, resulting in a final total of 88 patients. Patients whose operation lasted longer than 1 h received a statistically significant higher dose of radiation (183.83 cGYM2 vs. 368.22 cGYM2; p value 0.0002). Operations performed by a consultant resulted in less cumulative fluoroscopy time in comparison with those performed by a registrar or specialist registrar although this was not statistically significant (00:00:53 vs. 00:00:45; p vaue 0.38). Cumulative fluoroscopy time was less in dynamic hip screw compared to long intramedullary nails (00:00:39 vs. 00:01:29; p value <0.001) and short intramedullary nails (00:00:39 vs. 00:01:52; p value 0.387). Studies, which had a cumulative fluoroscopy time exceeding 50 secs, delivered a higher radiation dose (434.34cGYM2 vs. 150.51cGYM2; p value <0.001). We concluded that there is no significant impact in cumulative fluoroscopy time in operations performed by either a registrar or consultant. Dynamic hip screws have a lower fluoroscopy time in comparison with long intramedullary nails.

Enhanced recovery in lower limb arthroplasty in the Irish setting.

BACKGROUND: In the current economic climate of staff shortages and bed closures, orthopaedic surgeons must look for system efficiencies. Enhanced Recovery Programmes (ERP) have the potential not only to reduce length of stay (LOS) and concurrent costs but also to improve patient outcomes. The aim of this paper is to evaluate the effect of ERP for primary total hip arthroplasty (THA) and total knee arthroplasty (TKA) on length of stay (LOS) in the Irish Setting. METHODS: A single-surgeon retrospective case-control study was conducted comparing those who underwent primary lower limb arthroplasty before and after the introduction of an ERP. Patient medical and theatre records were used to determine the operation type, gender, age, LOS and readmission rates. RESULTS: Over the 2-year study period, a total of 310 patients underwent either THA (n = 244) or TKA (n = 66). The mean LOS was 8.79 days in the pre-ERP group and 5.1 days in the post-ERP group (p < 0.001). There was a significant correlation between LOS and age (p < 0.001). Gender or procedure type had no bearing on LOS for any of the subgroups (p > 0.1). CONCLUSIONS: ERP has the potential to significantly reduce overall length of stay after hip and knee arthroplasty and could have a considerable benefit in the Irish setting.

Risk factors for Merino ewe mortality on the Northern Tablelands of New South Wales, Australia.

OBJECTIVE: To measure the association of worm egg count (WEC), body weight (BW) and fat score (FS) with mortality in Merino ewes. METHODS: On six farms, Merino ewes (n = 1440) were yarded at approximately 3-month intervals for 2 years for a range of experimental measurements. Mortality was defined by failure to present at two consecutive measurement days and at next shearing. Survival analysis was conducted with phenotypic traits measured both as continuous variables and categorised appropriately for industry guidelines. RESULTS: Overall mortality was 10%, with most deaths occurring in autumn followed by winter. Age class (2006 drop vs mature-age ewes) did not affect mortality. High WEC, low BW and low FS significantly increased the risk of mortality. WEC > 1200 epg significantly increased risk of mortality in summer (risk ratio 3.76) and autumn (risk ratio 3.61) compared with the reference group. Risk of mortality increased 1.1-fold for each kilogram unit decrease in BW and 7-fold for each unit decrease in FS. CONCLUSIONS: Mortality of Merino ewes can be significantly reduced by management methods that reduce WEC, maintain BW and increase the FS. For Merino ewes on the Northern Tablelands of NSW, improved animal welfare and economic benefits may be achieved by maintaining sheep with WEC < 1200 epg, BW > 35 kg and FS > 2.5.

Imaging the spine for tumour and trauma--a national audit of practice in Irish hospitals.

BACKGROUND AND PURPOSE: The provision of appropriate spinal imaging in cases of acute injury as a consequence of trauma or tumour is becoming ever more challenging. This study assessed the use of multimodal radiological investigations in the management of spinal cord compression as a result of trauma and metastatic cancer in all major Irish hospitals. METHODS: We conducted a questionnaire of thirty four hospitals in an effort to assess the provision of these services to patients with possible spinal cord compromise. In all public hospitals the Emergency Department and/or the Orthopaedic Registrars were contacted and asked a series of questions relating to spinal clearance, spinal clearance protocols, CT and MRI scanning facilities and on site orthopaedic services. RESULTS: All centres participated in the study. 67.64% of centres routinely used a protocol in spinal clearance. In 87% of hospitals the Emergency department were responsible for clearing the spine. 85.3% of hospitals had CT availability during normal working hours (9-5) dropping to 47% availability after hours. MRI was available in 50% of hospitals, with surprisingly just two centres providing out of hours MRI imaging services. CONCLUSION: The provision of radiological services in the management of suspected spinal injuries in Irish hospitals is inadequate in comparison to international best practice. This is most marked in relation to CT and MRI.

The impact of spinal cord stimulation on physical function and sleep quality in individuals with failed back surgery syndrome: a systematic review.

The aim of this review was to determine the impact of spinal cord stimulation (SCS) on physical function and sleep quality in individuals with failed back surgery syndrome (FBSS). This review comprised three phases: an electronic database search (PubMed, Cinahl Plus, EMBASE, PsychInfo, Pedro, Cochrane Library) identified potential papers; these were screened for inclusion criteria, with extraction of data from accepted papers and rating of internal validity by two independent reviewers using the Effective Public Health Practice Project quality assessment tool, a tool designed to assess non-RCTs (randomized controlled trials) as well as RCTs. Strength of the evidence was rated using the Agency for Health Care Policy and Research guidelines. The search generated 13 quantitative papers that fulfilled the inclusion criteria; all 13 studies investigated the impact of SCS on physical function, and nine studies investigated the impact of SCS on sleep quality. Consistent evidence (level C) found that SCS positively affected physical function, with improvements in participation in activities of daily living, leisure, social and work-related activities. Similarly, consistent evidence (level C) found improvements in sleep quality following SCS. Improvements in sleep quantity, a reduction in awakenings and a decrease in sleep medication use were also noted (level D). The impact of SCS on cognitive function, i.e., memory and concentration, was also assessed using the same search strategy, no papers fulfilled the inclusion criteria for this study. Spinal cord stimulation effectively addressed many physical function and sleep problems associated with FBSS; however, there is a need for further high-quality objective investigations to support this.

No loss of production due to larval challenge in sheep given continuous anthelmintic treatment via a controlled release capsule.

This study aimed to quantify production loss due to larval challenge in sheep administered a controlled release albendazole capsule (CRC) and thus determine the suitability of CRC treated sheep as a proxy for worm-free sheep in grazing experiments. The experiment used an incomplete 2 × 3 latin square design with 81 Merino wethers. Sheep were either infected (INF) with mixed oral infection of albendazole-susceptible Haemonchus contortus, Trichostrongylus colubriformis, and Teladorsagia circumcincta (initial bolus then thrice weekly maintenance) or remained uninfected (UINF). Worm control treatments were with a CRC (CRCT), threshold treatment with a short-acting anthelmintic when worm egg count (WEC) exceeded 1500 epg (TT) or untreated (UT). The experiment was conducted in two 63-day periods (separated by a 14 day washout period) with infection treatments swapped between periods. A subset of animals was killed at the end of each period for worm counts and tissue sampling. Faecal worm egg count in UINF-UT reached 10,204 and 6078 epg at day 63 in periods 1 and 2, respectively, and remained 0 throughout in the CRT treatments. There was no difference in live weight gain or wool growth of INF-CRCT sheep (67 and 70 g/d) relative to UINF-CRCT (67 and 76 g/d). Live weight gain was significantly lower in INF-UT (27 g/d) and INF-TT (55 g/d) than UINF-UT (88 g/d) or UINF-TT (81 g/d) treatments. During the first infection period, greasy fleece weight growth was significantly lower in INF-UT (6.33 g/d) and INF-TT (6.37 g/d) than UINF-UT (7.80 g/d) or UINF-TT (7.32 g/d) treatments. The effects of infection on production persisted in INF-UT, but not INF-TT sheep for several weeks after termination of infection. Eosinophil counts were elevated in all infected groups and the antibody response to T. colubriformis was greater in INF-CRCT and INF-TT groups compared to uninfected sheep. Together, these results indicate that larval challenge in sheep with a CRC is mildly immunogenic but is not associated with production loss. The results also showed that the CRC itself reduced live weight gain and that anthelmintic treatment at a WEC threshold of 1500 epg reduces production loss during infections and prevents persistence of adverse effects following infection.

A case of organic solvent exposure and temporal lobe demyelination.

A 42-year-old, previously healthy man, developed dizziness and headaches. A CT scan revealed areas of demyelination in the left temporal lobe. He had been exposed to large amounts of organic solvents for most of his working life and as other possibilities could be excluded it was suspected that this was the cause.

Systemic, pulmonary, and coronary hemodynamic effects of labetalol in hypertensive subjects.

Long-term therapy with oral labetalol, an alpha- and beta-blocking agent, has been shown to effectively lower blood pressure and heart rate without decreasing cardiac output. We examined the hemodynamic effects of the acute intravenous administration of labetalol in nine hypertensive patients. Labetalol (0.6 +/- 0.1 mg/kg) promptly reduced arterial pressure, heart rate, and systemic vascular resistance without change in stroke volume. Heart rate responses to passive tilt and the Valsalva maneuver were significantly blunted. With isometric exercise, heart rate and mean arterial pressure increased significantly during labetalol therapy but less than in the pre-labetalol phase. In eight patients oral labetalol therapy was continued for six weeks (mean dose 1,050 +/- 105 mg/day), and hemodynamic evaluation was repeated. During oral labetalol therapy, decreases in arterial pressure and heart rate were sustained. Systemic vascular resistance was reduced in five of the eight patients. Hemodynamic responses to tilt, Valsalva maneuver, and handgrip were similar to those during intravenous administration. Coronary blood flow decreased, but coronary as well as pulmonary vascular resistances were unchanged. These data show the efficacy of intravenously administered labetalol in lowering blood pressure and systemic vascular resistance promptly. With long-term oral therapy, decreases in blood pressure are sustained. Labetalol does not appear to have significant effects on pulmonary or coronary vascular resistances.

Acquired dysfibrinogenemia in a hemophiliac with hepatoma: resolution of fibrinogen dysfunction following chemotherapy.

A 17-year-old male with previously undiagnosed congenital Factor IX deficiency (13%) presented with gastrointestinal bleeding and a hepatic mass. Prolonged thrombin and Reptilase times, which partially corrected with CaCl2 and a discrepancy between thrombin-clottable and immunoreactive plasma fibrinogen, suggested a dysfibrinogenemia. Laparotomy disclosed metastatic hepatoma. Adequate hemostasis was obtained with clotting factor replacement, but wound healing was delayed. Patient fibrinogen purified with 2.1 M glycine migrated normally on immunoelectrophoresis and 7.5% polyacrylamide-SDS gel electrophoresis. However, fibrin monomers prepared from purified patient fibrinogen displayed impaired aggregation at high and low ionic strengths when compared with fibrin monomers from normal and control Factor IX deficient subjects. Aggregation of normal monomers was delayed when mixed 1:1 with patient monomers. Fibrinopeptide release was normal, and total sialic acid content was similar to that of normal and control fibrinogens. Chemotherapy, consisting of 5-FU given via intra-arterial hepatic infusion, was accompanied by significant transient clinical improvement which coincided with correction of thrombin clotting times and fibrin monomer aggregation. Reappearance of fibrinogen dysfunction occurred with clinical deterioration prior to death from metastatic hepatoma and sepsis. This case is the first to corroborate the postulated tumor marker role of dysfibrinogenemia in a patient with hepatoma by documenting a direct relationship with response to chemotherapy.

Characteristics of inhibition of pancreatic secretion by isoproterenol.

The effect of isoproterenol on pancreatic secretion stimulated by the octapeptide of cholecystokinin (OP-CCK) was studied in dogs with gastric and pancreatic fistulas. Special precautions were taken to prevent entry of gastric acid into the duodenum and reflux of duodenal content into the stomach. OP-CCK increased volume and the outputs of bicarbonate and protein from the pancreas. Isoproterenol inhibited these pancreatic responses to OP-CCK, and the degree of inhibition was dose related. Propranolol blocked the inhibitory action of isoproterenol completely. Analysis of data by Michaelis-Menten kinetics revealed that there was competitive inhibition of protein output with noncompetitive inhibition of bicarbonate output. The experiments show that isoproterenol inhibits OP-CCK--stimulated pancreatic secretion by a beta-adrenergic mechanism. The kinetic analysis suggests that the intimate mechanisms involved in inhibition of protein and bicarbonate output by isoproterenol are different.

Canine gut receptors mediating pancreatic responses to luminal L-amino acids.

Pancreatic protein and bicarbonate outputs were measured in dogs with pancreatic fistulas receiving intravenous secretin while individual L-amino acids or mixtures of L-amino acids were perfused into proximal intestine, Both phenylalanine and tryptophan were potent stimuli of pancreatic secretion; alanine, leucine, and valine increased protein outputs but their effects were small and not statistically significant. Six other amino acids were ineffective. Tryptophan perfused together with phenylalanine augmented responses to phenylalanine; methionine, ineffective when perfused alone, did not alter responses to phenylalanine when perfused with the latter. Responses to phenylalanine perfused at concentrations above 8 mM were dependent on load and were mediated by lengths of proximal bowel greater than 10 cm.

Canine pancreatic response to intestinally perfused oligopeptides.

Although older work indicated that luminal peptides are stimulants of pancreatic secretion, these earlier experiments were performed with crude peptide mixtures containing amino acids that are also known stimulants. Furthermore, no information was provided about size or composition of stimulating peptides. For this reason, the problem was reinvestigated with commercially synthesized oligopeptides in dogs equipped with chronic gastric and pancreatic fistulas. Synthetic peptides at 30 mM concentrations were perfused into the proximal bowel when luminal pancreatic proteases were reduced to undetectable concentrations and dogs were receiving intravenous exogenous secretin infusions. Increases in pancreatic outputs of protein and bicarbonate were measured. Of the peptides tested, only glycylphenylalanine, glycyltryptophan, and phenylalanylglycine stimulated, whereas both di- and triglycine were without effect. It was concluded that some, but not all, oligopeptides in the gut lumen are stimulants of pancreatic secretion.

Canine pancreatic responses to intestinally perfused proteins and protein digests.

Pancreatic bicarbonate and protein secretory responses to intestinally perfused proteins or digests of proteins were measured in dogs with chronic gastric and pancreatic fistulas when luminalpancreatic protease concentrations were reduced to undetectable levels. Protein digests were analyzed for amino acid content, and various other indirect met-ods were used to assess the composition of the digest mixtures. Of five undigested proteins, none evoked more pancreatic secretion than a control perfusion with saline. Peptic digestion of these same proteins converted four of them to polypeptides that were poten stimuli of a pancreatic juice similar in HCO3-/protein ratios to that evoked by luminal amino acids. Dialyzed peptic digests of one of the proteins, bovine serum albumin (BSA), retained potency. Likewise, digestion of BSA with endogenous or exogenous pancreatic proteases converted the protein to a stimulus about equipotent with the peptic digest, though the composition of the pancreatic digests differed markedly from that of the peptic digests. We conclude that a) luminal peptides of four or more amino acids can stimulate the pancreas and b) during protein alimentation a wide array of luminal protein products may evoke pancreatic secretion.

Pancreatic secretion in response to an elemental diet and intravenous hyperalimentation.

Pancreatic exocrine responses to oral and intraduodenal administration of an elemental diet and to an intravenously administered hyperalimentation solution were determined in dogs with fistulas of the stomach and pancreas. Administration of an intraduodenal elemental diet prevented the responses to water and bicarbonate seen with oral administration but did not prevent the protein response. Intravenously administered hyperalimentation solution produced only minor effects on pancreatic secretion when compared with the elemental diet.