Biomarker-guided antibiotic stewardship in suspected ventilator-associated pneumonia (VAPrapid2): a randomised controlled trial and process evaluation.

BACKGROUND: Ventilator-associated pneumonia is the most common intensive care unit (ICU)-acquired infection, yet accurate diagnosis remains difficult, leading to overuse of antibiotics. Low concentrations of IL-1ß and IL-8 in bronchoalveolar lavage fluid have been validated as effective markers for exclusion of ventilator-associated pneumonia. The VAPrapid2 trial aimed to determine whether measurement of bronchoalveolar lavage fluid IL-1ß and IL-8 could effectively and safely improve antibiotic stewardship in patients with clinically suspected ventilator-associated pneumonia. METHODS: VAPrapid2 was a multicentre, randomised controlled trial in patients admitted to 24 ICUs from 17 National Health Service hospital trusts across England, Scotland, and Northern Ireland. Patients were screened for eligibility and included if they were 18 years or older, intubated and mechanically ventilated for at least 48 h, and had suspected ventilator-associated pneumonia. Patients were randomly assigned (1:1) to biomarker-guided recommendation on antibiotics (intervention group) or routine use of antibiotics (control group) using a web-based randomisation service hosted by Newcastle Clinical Trials Unit. Patients were randomised using randomly permuted blocks of size four and six and stratified by site, with allocation concealment. Clinicians were masked to patient assignment for an initial period until biomarker results were reported. Bronchoalveolar lavage was done in all patients, with concentrations of IL-1ß and IL-8 rapidly determined in bronchoalveolar lavage fluid from patients randomised to the biomarker-based antibiotic recommendation group. If concentrations were below a previously validated cutoff, clinicians were advised that ventilator-associated pneumonia was unlikely and to consider discontinuing antibiotics. Patients in the routine use of antibiotics group received antibiotics according to usual practice at sites. Microbiology was done on bronchoalveolar lavage fluid from all patients and ventilator-associated pneumonia was confirmed by at least 104 colony forming units per mL of bronchoalveolar lavage fluid. The primary outcome was the distribution of antibiotic-free days in the 7 days following bronchoalveolar lavage. Data were analysed on an intention-to-treat basis, with an additional per-protocol analysis that excluded patients randomly assigned to the intervention group who defaulted to routine use of antibiotics because of failure to return an adequate biomarker result. An embedded process evaluation assessed factors influencing trial adoption, recruitment, and decision making. This study is registered with ISRCTN, ISRCTN65937227, and ClinicalTrials.gov, NCT01972425. FINDINGS: Between Nov 6, 2013, and Sept 13, 2016, 360 patients were screened for inclusion in the study. 146 patients were ineligible, leaving 214 who were recruited to the study. Four patients were excluded before randomisation, meaning that 210 patients were randomly assigned to biomarker-guided recommendation on antibiotics (n=104) or routine use of antibiotics (n=106). One patient in the biomarker-guided recommendation group was withdrawn by the clinical team before bronchoscopy and so was excluded from the intention-to-treat analysis. We found no significant difference in the primary outcome of the distribution of antibiotic-free days in the 7 days following bronchoalveolar lavage in the intention-to-treat analysis (p=0·58). Bronchoalveolar lavage was associated with a small and transient increase in oxygen requirements. Established prescribing practices, reluctance for bronchoalveolar lavage, and dependence on a chain of trial-related procedures emerged as factors that impaired trial processes. INTERPRETATION: Antibiotic use remains high in patients with suspected ventilator-associated pneumonia. Antibiotic stewardship was not improved by a rapid, highly sensitive rule-out test. Prescribing culture, rather than poor test performance, might explain this absence of effect. FUNDING: UK Department of Health and the Wellcome Trust.

Community-based surveillance of unaccompanied and separated children in drought-affected northern Ethiopia.

BACKGROUND: Children separated from their caregivers in humanitarian emergencies are vulnerable to multiple risks. However, no field-tested methods exist to capture ongoing changes in the frequency and nature of separation in these contexts over the course of a protracted crisis. METHODS: Recognizing this gap, a mobile phone-based surveillance system was established in a drought-affected district in northern Ethiopia to assess the feasibility of using community focal points to monitor cases of unaccompanied and separated children. A total of 29 focal points were recruited through village elections from 10 villages in the district. Feasibility was assessed directly by measuring the number and quality of messages sent by the focal points each week. The team also evaluated the implementation process and any challenges that arose through observations and key informant interviews with focal points at the conclusion of the project measuring frequency of employing various information gathering techniques, challenges faced, and perceptions of community expectations. Likert scales were used to measure overall satisfaction with the experience of being a focal point, self-assessed difficulty of being a focal point, perceived likelihood of cases captured, and motivation. RESULTS: Over a six-month period, the focal points reported 48 cases of separation. The majority of separated children (64.6%) were 10 years of age or older. Work was a major driver of separation, especially for boys. Age, sex, role in community, and density of community had no statistically significant impact on focal point performance in terms of frequency, accuracy, or consistency of messages. The focal points themselves reported high levels of motivation, but suggested several areas for improvement in the surveillance system. CONCLUSIONS: Without the surveillance system, most of these children would have otherwise been unrecognized. From a technical standpoint the system was successful and resilient in the face of unexpected external challenges. However, focal point participation and accuracy was variable over time and across groups and diminished towards the later months of the study, suggesting that the community-based approach may require additional supports to ensure that the surveillance system is able to accurately capture trends over time.

African bush elephants respond to a honeybee alarm pheromone blend.

We here report the responses of African bush elephants (Loxodonta africana) to a crude approximation of the honeybee alarm pheromone blend. We show that the elephants had an avoidance response to the semiochemical blend. The use of honeybee alarm pheromones to manage elephant movements in a non-invasive manner, using natural cues to which elephants may have an evolved response, holds potential for development of new options for an integrated system for elephant movement management and protection.

A large outbreak of Hepatitis E virus genotype 1 infection in an urban setting in Chad likely linked to household level transmission factors, 2016-2017.

BACKGROUND: In September 2016, three acutely jaundiced (AJS) pregnant women were admitted to Am Timan Hospital, eastern Chad. We described the outbreak and conducted a case test-negative study to identify risk factors for this genotype of HEV in an acute outbreak setting. METHODS: Active case finding using a community based surveillance network identified suspected AJS cases. Pregnant or visibly ill AJS cases presenting at hospital were tested with Assure® IgM HEV rapid diagnostic tests (RDTs) and some with Polymerase Chain Reaction (PCR) in Amsterdam; confirmed cases were RDT-positive and controls were RDT-negative. All answered questions around: demographics, household makeup, area of residence, handwashing practices, water collection behaviour and clinical presentation. We calculated unadjusted odds ratios (ORs) and 95% confidence intervals (95% CI). RESULTS: Between September and April 2017, 1443 AJS cases (1293 confirmed) were detected in the town(attack rate: 2%; estimated 65,000 population). PCR testing confirmed HEV genotype 1e. HEV RDTs were used for 250 AJS cases; 100 (40%) were confirmed. Risk factors for HEV infection, included: having at least two children under the age of 5 years (OR 2.1, 95%CI 1.1-4.3), having another household member with jaundice (OR 2.4, 95%CI 0.90-6.3) and, with borderline significance, living in the neighbourhoods of Riad (OR 3.8, 95%CI 1.0-1.8) or Ridina (OR 3.3, 95%CI 1.0-12.6). Cases were more likely to present with vomiting (OR 3.2, 9%CI 1.4-7.9) than controls; possibly due to selection bias. Cases were non-significantly less likely to report always washing hands before meals compared with controls (OR 0.33, 95%CI 0.1-1.1). DISCUSSION: Our study suggests household factors and area of residence (possibly linked to access to water and sanitation) play a role in HEV transmission; which could inform future outbreak responses. Ongoing sero-prevalence studies will elucidate more aspects of transmission dynamics of this virus with genotype 1e.

Diverse modes of galacto-specific carbohydrate recognition by a family 31 glycoside hydrolase from Clostridium perfringens.

Clostridium perfringens is a commensal member of the human gut microbiome and an opportunistic pathogen whose genome encodes a suite of putative large, multi-modular carbohydrate-active enzymes that appears to play a role in the interaction of the bacterium with mucin-based carbohydrates. Among the most complex of these is an enzyme that contains a presumed catalytic module belonging to glycoside hydrolase family 31 (GH31). This large enzyme, which based on its possession of a GH31 module is a predicted α-glucosidase, contains a variety of non-catalytic ancillary modules, including three CBM32 modules that to date have not been characterized. NMR-based experiments demonstrated a preference of each module for galacto-configured sugars, including the ability of all three CBM32s to recognize the common mucin monosaccharide GalNAc. X-ray crystal structures of the CpGH31 CBM32s, both in apo form and bound to GalNAc, revealed the finely-tuned molecular strategies employed by these sequentially variable CBM32s in coordinating a common ligand. The data highlight that sequence similarities to previously characterized CBMs alone are insufficient for identifying the molecular mechanism of ligand binding by individual CBMs. Furthermore, the overlapping ligand binding profiles of the three CBMs provide a fail-safe mechanism for the recognition of GalNAc among the dense eukaryotic carbohydrate networks of the colonic mucosa. These findings expand our understanding of ligand targeting by large, multi-modular carbohydrate-active enzymes, and offer unique insights into of the expanding ligand-binding preferences and binding site topologies observed in CBM32s.

Twelve tips on how to establish a new undergraduate firm on a critical care unit.

BACKGROUND: Little is known about undergraduate teaching in critical care unit (CrCU) and many undergraduate curricula lack placements in CrCU. AIMS: To describe how our CrCU succeeded in developing a novel placement for Year 3 undergraduate medical students. METHODS: Particular emphasis was placed on a robust timetable incorporating a variety of activities, a dedicated and thorough induction, and a mix of teaching methods such as formal and informal, consultant-led, and skills. Services allied to CrCU were also utilized. RESULTS: Our new firm has exceeded all expectations and, based on student feedback, received the "Firm of the Year" award for several years in succession. It now serves as a model of undergraduate teaching in our hospital. CONCLUSIONS: Educationalists and intensivists should work together to unlock the full potential of this rich learning environment. Professional societies in critical care medicine should take the opportunity to develop more interest in undergraduate medical education.

Assessing the use of the neighborhood method to estimate the prevalence of child separation: a pilot in North Kivu, DRC.

BACKGROUND: This article reports on the use of the 'neighborhood method' to measure the prevalence and basic characteristics of children who became separated from their parents or usual caregivers subsequent to an attack by the M23 militia group in North Kivu, Democratic Republic of the Congo. METHODS: A two-stage household cluster survey was conducted in 522 households in North Kivu in August 2014. Heads of households were asked about separated children in their household, as well as the households of their two closest neighbors. Separation was tracked in terms of children who arrived into the households after the M23 attacks and children who departed from the households after the recall event without their parent(s) or usual caregiver. For a subset of 44 neighbor pairs, respondents were asked to report on the same household to assess inter-rater reliability. Data about primary respondents and their neighbors were assessed to determine whether the neighborhood method was a comparable, reliable and efficient alternative to a traditional household survey about separated children. RESULTS: The prevalence of separated children who arrived was 8.52 % [95 % CI: 6.75-10.75] in primary households and 4.46 % [95 % CI: 3.60-5.52] in neighbors' households (p-value = 0.0000). The prevalence of separated children who departed was 4.98 % [95 % CI: 3.45-7.19] in primary households and 3.19 % [95 % CI: 2.27-4.48] in neighbors' households (p-value = 0.0110). Kappa coefficients for the neighbor pairs indicated fair to moderate agreement for most demographic variables, but agreement was generally higher for variables related to current characteristics of the households than for variables describing the household in the past, especially before the M23 attack. Compared to a traditional household survey with similar power, the neighborhood method reduced data collection time by 50 % and lowered costs by 36 %. CONCLUSION: This pilot showed that, for measuring separated children in North Kivu, the results from neighbor households significantly underestimated the prevalence of separation when compared to data collected from respondents directly. Reliability was mixed. Although the neighborhood method did not yield valid results in this setting, given the potential the method holds to save scarce resources in humanitarian settings, additional pilots to refine and evaluate its validity and reliability in settings with shorter recall periods are recommended.

Estimating child separation in emergencies: Results from North Kivu.

Children who are separated from their families and usual caregivers in emergencies face a multitude of risks to their health and wellbeing. This study presents findings from the first known population-based estimation of separation in an emergency setting. Point prevalence and basic characteristics were measured to inform programming, policies and funding for affected populations. A household survey was carried out in the Democratic Republic of the Congo to estimate separation subsequent to an attack by the M23 militia group. Separation was tracked in terms of children arriving into the household after the M23 attacks and children who had departed from the household after the recall event without their parent or usual caregiver. Five hundred and twenty-two households were surveyed. In the sample of 2,197 children living in the respondents' homes at the time of data collection, 8.47% (n=186) were separated children who had newly arrived in the household since the M23 attack. In the sample of 2,034 children living in the respondents' homes prior to the M23 attack, 5.31% (n=108) children had since departed from the household, resulting in separation from their parents or usual caregivers. Characteristics of children who arrived and children who departed diverged in terms of age, reasons for separation and frequency of unaccompaniment. The findings indicate the potential for population-based estimation of separation to be replicated in emergency settings to inform funding appeals and programmatic response.

Community-based surveillance to monitor trends in unaccompanied and separated children in eastern DRC.

Children who are separated from their families and usual caregivers in emergencies face a multitude of risks. The humanitarian community lacks methods to systematically capture changes in the frequency and nature of such separations over time. A mobile phone-based community surveillance system was piloted in the Democratic Republic of the Congo. The goal was to identify new cases of unaccompanied and separated children on a weekly basis. Over an 11-week period, community focal points reported 62 cases of separation across 10 communities. The majority of children had been under the care of their parents prior to separation. More than half of the children were unaccompanied, meaning that they were living without an adult relative or customary caregiver. The pilot results suggest that implementing a mobile phone-based surveillance system in a humanitarian setting may be feasible and cost-effective and fills a critical gap in the measurement of separated and unaccompanied children in emergencies. A longer pilot to better understand how the system performs over time is recommended.

Diagnostic accuracy of pulmonary host inflammatory mediators in the exclusion of ventilator-acquired pneumonia.

BACKGROUND: Excessive use of empirical antibiotics is common in critically ill patients. Rapid biomarker-based exclusion of infection may improve antibiotic stewardship in ventilator-acquired pneumonia (VAP). However, successful validation of the usefulness of potential markers in this setting is exceptionally rare. OBJECTIVES: We sought to validate the capacity for specific host inflammatory mediators to exclude pneumonia in patients with suspected VAP. METHODS: A prospective, multicentre, validation study of patients with suspected VAP was conducted in 12 intensive care units. VAP was confirmed following bronchoscopy by culture of a potential pathogen in bronchoalveolar lavage fluid (BALF) at >10(4) colony forming units per millilitre (cfu/mL). Interleukin-1 beta (IL-1ß), IL-8, matrix metalloproteinase-8 (MMP-8), MMP-9 and human neutrophil elastase (HNE) were quantified in BALF. Diagnostic utility was determined for biomarkers individually and in combination. RESULTS: Paired BALF culture and biomarker results were available for 150 patients. 53 patients (35%) had VAP and 97 (65%) patients formed the non-VAP group. All biomarkers were significantly higher in the VAP group (p<0.001). The area under the receiver operator characteristic curve for IL-1ß was 0.81; IL-8, 0.74; MMP-8, 0.76; MMP-9, 0.79 and HNE, 0.78. A combination of IL-1ß and IL-8, at the optimal cut-point, excluded VAP with a sensitivity of 100%, a specificity of 44.3% and a post-test probability of 0% (95% CI 0% to 9.2%). CONCLUSIONS: Low BALF IL-1ß in combination with IL-8 confidently excludes VAP and could form a rapid biomarker-based rule-out test, with the potential to improve antibiotic stewardship.

Survival after cardiac arrest and severe lactic acidosis (pH 6.61) due to haemorrhage.

This paper describes a 21-year-old man who presented to the emergency department with a knife wound to his buttock. He had a witnessed cardiac arrest with pulseless electrical activity in hospital as a result of further haemorrhage. His post-resuscitation arterial blood gas revealed a severe lactic acidosis (pH 6.61, lactate 22.0 mmol/l). Despite poor expectations he went on to make a full neurological recovery. To the authors' knowledge, he had the fourth-lowest pH for a cardiac arrest survivor with normal neurology. Severe lactic acidosis occurs post cardiac arrest due to imbalance between cellular oxygen supply and demand. Severe lactic acidosis is associated with hypoxic brain injury but has a low specificity in its prediction. The case illustrates that, especially in younger adults, severe lactic acidosis may be a poor predictor of outcome if it reflects a period of relative hypoperfusion preceding cardiac arrest.

The extracellular calcium-sensing receptor reciprocally regulates the secretion of BMP-2 and the BMP antagonist Noggin in colonic myofibroblasts.

To understand whether postprandial extracellular Ca(2+) (Ca(o)(2+)) changes were related to intestinal epithelial homeostasis, we performed array analysis on extracellular calcium-sensing receptor (CaSR)-expressing colonic myofibroblasts (18Co cells) and observed increases in bone morphogenetic protein (BMP)-2 transcripts. The present experiments demonstrated that regulated secretion of BMP-2 occurs in response to CaSR activation of these cells and revealed a new property of BMP-2 on the intestinal barrier. Activation by Ca(o)(2+), spermine, GdCl(3), or neomycin sulfate of 18Co cells or primary isolates of myofibroblasts from the normal human colon stimulated both the synthesis (RT-PCR) and secretion (ELISA) of BMP-2. Transient transfection with short interfering RNA against CaSR completely inhibited BMP-2 secretion. Transient transfection with dominant negative CaSR (R185Q) increased the EC(50) of Ca(o)(2+) (5.7 vs. 2.3 mM). Upregulation of BMP-2 transcript and secretion occurring within 3 h of CaSR activation was prevented by actinomycin D. CaSR-mediated BMP-2 synthesis and secretion required phosphatidylinositol 3-kinase activation (as assessed by phospho-Akt generation). Exogenous BMP-2 and conditioned medium from CaSR-stimulated 18Co cells accelerated restitution in wounded postconfluent Caco-2 cells. Exogenous BMP-2 and conditioned medium from CaSR-stimulated 18Co cells increased the transepithelial resistance of low- and high-resistance T-84 epithelial monolayers. CaSR stimulation of T-84 epithelia and colonic myofibroblasts downregulated the BMP family antagonist Noggin, as assessed by RT-PCR and Western blot analysis. Together, our data suggest that the CaSR mediates the effective concentration of BMP-2 in the intestine, which leads to enhanced repair and barrier development.

An apolipoprotein(a) peptide delays chylomicron remnant clearance and increases plasma remnant lipoproteins and atherosclerosis in vivo.

OBJECTIVE: Humans with high expression of apolipoprotein(a) [apo(a)] and high plasma levels of lipoprotein(a) [Lp(a)] are at increased risk for atherosclerosis, but the mechanism is not known. We have previously shown that the KIV(5-8) domain of apo(a) has unique cell-surface binding properties, and naturally occurring fragments of apo(a) encompassing this domain are thought to be atherogenic in humans. To investigate the effect of KIV(5-8) on lipoprotein metabolism and atherosclerosis in vivo, we created several independent lines of liver-targeted KIV(5-8) transgenic mice. METHODS AND RESULTS: The transgenic mice have plasma apo(a) peptide concentrations that are similar to Lp(a) concentrations in humans at risk for coronary artery disease. Remarkably, the transgenic mice had a 2- to 4-fold increase in cholesterol-rich remnant lipoproteins (RLPs) when fed a cholesterol-rich diet, and a 5- to 20-fold increase in atherosclerosis lesion area in the aortic root. Using an in vivo clearance study, we found only slight differences in the triglyceride and apolipoprotein B secretion rates between the 2 groups of mice, suggesting an RLP clearance defect. Using an isolated perfused mouse liver system, we showed that transgenic livers had a slower rate of RLP removal, which was retarded further when KIV(5-8), full-length apo(a), or Lp(a) were added to the perfusate. An apo(a) peptide that does not interact with cells, K(IV2)3, did not retard RLP removal, and low-density lipoprotein (LDL) had a much smaller effect than Lp(a). CONCLUSIONS: We propose that high levels of apo(a)/Lp(a), perhaps acting via a specific cell-surface binding domain, inhibit hepatic clearance of remnants, leading to high plasma levels of RLPs and markedly enhanced atherosclerosis. We speculate that the KIV(5-8) region of apo(a) competes with one or more receptors for remnant clearance in the liver and that this process may represent one mechanism accounting for increased atherosclerosis in humans with high secretion levels of apo(a).

The apolipoprotein(a) component of lipoprotein(a) mediates binding to laminin: contribution to selective retention of lipoprotein(a) in atherosclerotic lesions.

Lipoprotein(a) [Lp(a)] entrapment by vascular extracellular matrix may be important in atherogenesis. We sought to determine whether laminin, a major component of the basal membrane, may contribute to Lp(a) retention in the arterial wall. First, immunohistochemistry experiments were performed to examine the relative distribution of Lp(a) and laminin in human carotid artery specimens. There was a high degree of co-localization of Lp(a) and laminin in atherosclerotic specimens, but not in non-atherosclerotic sections. We then studied the binding interaction between Lp(a) and laminin in vitro. ELISA experiments showed that native Lp(a) particles and 17K and 12K recombinant apolipoprotein(a) [r-apo(a)] variants interacted strongly with laminin whereas LDL, apoB-100, and the truncated KIV(6-P), KIV(8-P), and KIV(9-P) r-apo(a) variants did not. Overall, the ELISA data demonstrated that Lp(a) binding to laminin is mediated by apo(a) and a combination of the lysine analogue epsilon-aminocaproic acid and salt effectively decreases apo(a) binding to laminin. Secondary binding analyses with 125I-labeled r-apo(a) revealed equilibrium dissociation constants (K(d)) of 180 and 360 nM for the 17K and 12K variants binding to laminin, respectively. Such similar K(d) values between these two r-apo(a) variants suggest that isoform size does not appear to influence apo(a) binding to laminin. In summary, our data suggest that laminin may bind to apo(a) in the atherosclerotic intima, thus contributing to the selective retention of Lp(a) in this milieu.

Definition of the structural elements in plasminogen required for high-affinity binding to apolipoprotein(a): a study utilizing surface plasmon resonance.

Lipoprotein(a) [Lp(a)] is suggested to link atherosclerosis and thrombosis owing to the similarity between the apolipoprotein(a) [apo(a)] moiety of Lp(a) and plasminogen. Lp(a) may interfere with tPA-mediated plasminogen activation in fibrinolysis, thereby generating a hypercoaguable state in vivo. The present study employed surface plasmon resonance (SPR) to examine the binding interaction between plasminogen and a physiologically relevant, 17-kringle recombinant apo(a) species [17K r-apo(a)] in real time. Native, intact Glu(1)-plasminogen bound to apo(a) with substantially higher affinity (K(D) approximately 0.3 microM) compared to a series of plasminogen fragments (K1-5, K1-3, K4, K5P, and tail domain) that interacted weakly with apo(a) (K(D) > 50 microM). Treatment of Glu(1)-plasminogen with citraconic anhydride (a lysine modification reagent) completely abolished binding to wild-type 17K r-apo(a), whereas citraconylated 17K r-apo(a) decreased binding to wild-type Glu(1)-plasminogen by approximately 50%; inhibition of binding was also observed using the lysine analogue epsilon-aminocaproic acid. Whereas native Glu(1)-plasminogen exhibited monophasic binding to 17K r-apo(a), truncated Lys(78)-plasminogen exhibited biphasic binding. Altering Glu(1)-plasminogen from its native, closed conformation (in chloride buffer) to an open conformation (in acetate buffer) also yielded biphasic isotherms. These SPR data are consistent with a two-state kinetic model in which a conformational change in the plasminogen-apo(a) complex may occur following the initial binding event. Differential binding kinetics between Glu(1)-/Lys(78)-plasminogen and apo(a) may explain why Lp(a) is a stronger inhibitor of tPA-mediated Glu(1)-plasminogen activation compared to Lys(78)-plasminogen activation.

Transureteral saline perfusion to obtain renal hypothermia: potential application in laparoscopic partial nephrectomy.

BACKGROUND: Partial nephrectomy for resection of renal tumors often requires renal artery clamping and external renal cooling using ice-slush. Laparoscopic surgery precludes traditional ice-slush cooling. To facilitate renal cooling during laparoscopic partial nephrectomy, we investigated a method of intrarenal cooling by retrograde transureteral iced saline perfusion. METHODS: Open laparotomy was performed in 6 pigs. After atraumatic renal artery clamping, one kidney was cooled externally by using standard ice-slush; the other was cooled transureterally. For transureteral cooling, the ureter was cannulated with a double lumen 12 Fr catheter. Chilled saline (4 degrees C) irrigation was flushed through the catheter into the renal pelvis (16.7 mL/min) and allowed to drain via the second lumen of the catheter. Using a 30-gauge hypodermic thermometer, kidney temperatures were measured at 5-minute intervals for 30 minutes at 3 locations and 2 depths (0.5 cm and 1.5 cm). The animals were euthanized, and the kidneys were harvested for histologic examination. RESULTS: Renal cooling was achieved with both external and transureteral cooling. However, lower (5.0 versus 26.1 degrees C, P<0.001) parenchymal temperatures were achieved more rapidly with external renal cooling. During transureteral cooling, medullary (1.5 cm) temperatures were lower than cortical (0.5 cm) temperatures were; this difference did not reach statistical significance. CONCLUSIONS: Although renal hypothermia can be achieved by transureteral iced saline infusion, external cooling by using ice-slush appears to be more efficient in the porcine model. With refinement of the technique, intrarenal cooling via a transureteral approach may allow more effective cooling of the renal medulla, and limit warm ischemia during laparoscopic partial nephrectomy.

Prostate carcinoma among men with human immunodeficiency virus infection.

BACKGROUND: Several malignancies are known to occur more frequently in individuals with human immunodeficiency virus (HIV) infection. To determine the incidence of prostate carcinoma in men with HIV infection, the authors initiated a prostate carcinoma screening program in a large HIV clinic. METHODS: Beginning in February 2002, monitoring of prostate-specific antigen (PSA) levels and digital rectal examination (DRE) were included in the routine annual health maintenance provided to men with HIV infection age > or = 35 years who were followed in the infectious disease clinic at the Naval Medical Center San Diego. All men with prostate carcinoma in this population over the last 2 years were reviewed. Demographic data (age, ethnicity), duration of HIV infection, laboratory values (CD4 counts and HIV viral load), and medication use were determined by medical record review. Men with elevated PSA levels (levels above age-adjusted PSA values or PSA velocity > or = 0.75 ng/mL per year) or abnormal DRE results were referred for urologic evaluation. Comparisons between groups were performed using a logistic regression model and the Fisher exact test. Multivariate analysis was performed by logistic regression to determine relations between prostate carcinoma and patient characteristics. RESULTS: Two hundred sixty-nine men age > or = 35 years (mean age, 43.4 years; range, 35-72years) underwent prostate carcinoma screening by DRE, and 216 men also received PSA testing. Overall, 56.3% of the patients were white, 28.7% were African American, and 15% were of other racial ethnicity. Of the 216 men, 7 (3.2%) had elevated PSA values, and none had abnormal DRE results. Three patients were diagnosed with prostatitis (PSA range, 3.3-25.7 ng/mL), and 1 patient had high-grade prostatic intraepithelial neoplasia, which was determined after a biopsy was performed. Repeat PSA evaluations were within normal limits for the remaining three patients. Review of the cohort during the 2-year period before the current study was initiated revealed 5 additional cases of prostate neoplasia. Prostate carcinoma was common (4 of 11 men, 36.4%) in men age > 60 years and occurred with relatively preserved CD4 counts (mean, 509 cells/mm(3)). In multivariate analysis, African-American race (P = 0.020) and duration of HIV infection (P = 0.047) were found to be associated with the development of prostate carcinoma. CONCLUSIONS: Prostate carcinoma screening identified abnormal PSA values in 3.2% of the HIV-positive cohort, many associated with prostatitis. Prostate carcinoma was common in older men and was associated with duration of HIV infection. As the life expectancy of men with HIV infection increases, prostate carcinoma screening will become increasingly important in this population.