Bacteriuria in patients with stented ureters: predictors of infection in patients presenting to the hospital and when not to treat

PURPOSE

Patients with ureteric stents have symptoms that overlap with infection symptoms. Thus, clinicians unnecessarily give antibiotics to stented patients with bacteriuria despite guidelines. In stented patients, little is known about risk factors for developing bacteriuria or urosepsis. The objectives were to identify the frequency and risk factors for developing bacteriuria and urosepsis in patients with stents.

METHODS

In this retrospective cohort study, we reviewed patients with ureteric stents placed or exchanged over 1 year. We examined associations between bacteriuria or urosepsis and host risk factors. Univariable and multivariable logistic analyses were performed.

RESULTS

Of 286 patients (mean age: 57.2 years), 167 (58.4%) were male. The main stent indications were stone, stricture, cancer and extrinsic compression. The median stented period was 61 days. The frequency of bacteriuria was 59/286 (21%). ASA status 3 and 4 had 5 times the odds of having bacteriuria relative to ASA status 1. Stent duration > 2 months had 5.5 times the odds relative to ≤ 2 months. Urosepsis was infrequent, 13/286 (4.5%). Five patients had bacteraemia. A stent duration over 2 months had nearly 6 times the odds of urosepsis.

CONCLUSION

ASA status higher than 2 and stent time greater than 2 months raise the odds of developing bacteriuria. A stent duration longer than 2 months was the only predictor of urosepsis. Though 21% of patients had bacteriuria, 4.5% had urosepsis. Hence, bacteriuria without sepsis should not be treated with antibiotics, thus aiding antimicrobial stewardship.

Nosocomial outbreak in a respiratory ward caused by the SARS-CoV-2 Omicron BA 5.2.1 subvariant associated with non-severe illness in vaccinated patients

In this short report, we describe an outbreak of COVID-19 caused by Omicron subvariant BA.5.2.1 in highly vaccinated patients in a respiratory ward in a large acute general hospital in North West London, United Kingdom. The attack rate was high (14/33 (42%)) but the clinical impact was relatively non-severe including in patients who were at high risk of severe COVID-19. Twelve of fourteen patients had COVID-19 vaccinations. There was only one death due to COVID-19 pneumonitis. The findings of this outbreak investigation suggest that while the transmissibility of Omicron BA.5.2.1 subvariant is high, infections caused by this strain are non-severe in vaccinated patients, even if they are at high risk of severe COVID-19 infection.

Population genetics of group B Streptococcus from maternal carriage in an ethnically diverse community in London

Introduction

Maternal immunization against Group B Streptococcus (GBS) has the potential to significantly reduce the burden of neonatal GBS infections. Population genetics of GBS from maternal carriage can offer key insights into vaccine target distribution.

Methods

In this study we characterized the population structure of GBS isolates from maternal carriage (n = 535) in an ethnically diverse community in London, using whole genome sequencing.

Results

The isolates clustered into nine clonal complexes (CCs) but the majority (95%) belonged to five lineages: CC1 (26%), CC19 (26%), CC23 (20%), CC17 (13%) and CC8/10 (10%). Nine serotypes were identified, the most common were serotypes III (26%), V (21%), II (19%) and Ia (19%). Other serotypes (Ib, IV, VI, VII, IX) represented less than 10% of all isolates each. Intra-lineage serotype diversity was observed in all major CCs but was highest in CC1, which revealed nine serotypes. Nearly all isolates (99%) carried at least one of the four alpha family protein genes (alpha, alp1, alp23, and rib). All isolates were susceptible to penicillin. We found 21% and 13% of isolates to be resistant to clarithromycin and clindamycin, respectively. Prevalence of macrolide-lincosamide-streptogramin B (MLS_B) resistance genes was 22% and they were most common in CC19 (37%) and CC1 (28%), and isolates with serotypes V (38%) and IV (32%). We identified some associations between maternal ethnicity and GBS population structure. Serotype Ib was significantly less common among the South Asian compared to Black women (S. Asian: 3/142, Black: 15/135, p = 0.03). There was also a significantly lower proportion of CC1 isolates among the White other (24/142) in comparison to Black (43/135) and S. Asian (44/142) women (p = 0.04). We found a significantly higher proportion of CC17 isolates among the White other compared to S. Asian women (White other: 32/142, S. Asian: 10/142, p = 0.004).

Conclusion

Our study showed high prevalence of GBS vaccine targets among isolates from pregnant women in London. However, the observed serotype diversity in CC1 and high prevalence of MLS_B resistance genes in CC19 demonstrates presence of high risk lineages, which might act as a reservoir of non-vaccine strains and antimicrobial resistance determinants.

Utility of the FebriDx point-of-care assay in supporting a triage algorithm for medical admissions with possible COVID-19: an observational cohort study

OBJECTIVE

To evaluate a triage algorithm used to identify and isolate patients with suspected COVID-19 among medical patients needing admission to hospital using simple clinical criteria and the FebriDx assay.

DESIGN

Retrospective observational cohort.

SETTING

Large acute National Health Service hospital in London, UK.

PARTICIPANTS

All medical admissions from the emergency department between 10 August 2020 and 4 November 2020 with a valid SARS-CoV-2 RT-PCR result.

INTERVENTIONS

Medical admissions were triaged as likely, possible or unlikely COVID-19 based on clinical criteria. Patients triaged as possible COVID-19 underwent FebriDx lateral flow assay on capillary blood, and those positive for myxovirus resistance protein A (a host response protein) were managed as likely COVID-19.

PRIMARY OUTCOME MEASURES

Diagnostic accuracy (sensitivity, specificity and predictive values) of the algorithm and the FebriDx assay using SARS-CoV-2 RT-PCR from nasopharyngeal swabs as the reference standard.

RESULTS

4.0% (136) of 3443 medical admissions had RT-PCR confirmed COVID-19. Prevalence of COVID-19 was 46% (80/175) in those triaged as likely, 4.1% (50/1225) in possible and 0.3% (6/2033) in unlikely COVID-19. Using a SARS-CoV-2 RT-PCR reference standard, clinical triage had sensitivity of 96% (95% CI 91% to 98%) and specificity of 61.5% (95% CI 59.8% to 63.1%), while the triage algorithm including FebriDx had sensitivity of 93% (95% CI 87% to 96%) and specificity of 86.4% (95% CI 85.2% to 87.5%). While 2033 patients were deemed not to require isolation using clinical criteria alone, the addition of FebriDx to clinical triage allowed a further 826 patients to be released from isolation, reducing the need for isolation rooms by 9.5 per day, 95% CI 8.9 to 10.2. Ten patients missed by the algorithm had mild or asymptomatic COVID-19.

CONCLUSIONS

A triage algorithm including the FebriDx assay had good sensitivity and was useful to 'rule-out' COVID-19 among medical admissions to hospital.

An outbreak caused by the SARS-CoV-2 Delta (B.1.617.2) variant in a care home after partial vaccination with a single dose of the COVID-19 vaccine Vaxzevria, London, England, April 2021

We investigated a COVID-19 outbreak of the SARS-CoV-2 Delta variant of concern in a London care home, where 8/21 residents and 14/21 staff had received a single dose of Vaxzevria (ChAdOx1-S; AstraZeneca) vaccine. We identified 24 SARS-CoV-2 infections (16 residents, 8 staff) among 40 individuals (19 residents, 21 staff); four (3 residents, 1 staff) were hospitalised, and none died. The attack rate after one vaccine dose was 35.7% (5/14) for staff and 81.3% (13/16) for residents.

A case of neck abscess caused by rare hypervirulent Klebsiella pneumoniae, capsular type K20 and sequence type 420

Background

This case report describes a neck abscess caused by a strain of Hypervirulent Klebsiella pneumoniae in a middle aged man with diabetes without a history of travel to East and South East Asia. This case report is of notable significance as Hypervirulent Klebsiella pneumoniae neck abscesses are rarely seen in the UK and are very infrequently documented in individuals who have not first travelled to the high prevalence areas of East and South East Asia.

Case presentation

This case report describes a 53 year old diabetic man who contracted a Hypervirulent Klebsiella pneumoniae neck abscess which led to the development of sepsis. Klebsiella pneumoniae was cultured from blood cultures and fluid aspirated from the abscess grew the pathogen with same antimicrobial susceptibility. Hypervirulence was demonstrated after the samples were analysed, at the Antimicrobial Resistance and Healthcare Associated Infections Reference Unit Public Health England Colindale, and found to contain the K20 (rmp)A and rmpA2 virulence genes.

Discussion

Hypervirulent Klebsiella pneumoniae is a Gram-negative, encapsulated, non-motile bacillus notable for its ability to metastatically spread and cause potentially life threatening infections in otherwise healthy adults, but especially in those with diabetes. Genes responsible for the production of hyperviscous mucoid polysaccharide capsules and siderophores, such as those isolated in this case, enable the bacteria to more efficiently evade the hosts immune system and disseminate and invade surrounding and distant tissues. Data from Public Health England shows Hypervirulent Klebsiella pneumoniae are rare in the UK. A review of current literature also showed Hypervirulent Klebsiella pneumoniae almost exclusively occur in those who have traveled to East and South East Asia.

Conclusions

This case reported a rare Hypervirulent Klebsiella pneumoniae neck abscess outside of, and without travel to, East and South East Asia. This raises concerns about future, potentially life threatening, Hypervirulent Klebsiella pneumoniae infections becoming more widespread without the need for endemic travel. This concern is further exacerbated by the growing global challenge of antimicrobial resistance.

An observational cohort study of bacterial co-infection and implications for empirical antibiotic therapy in patients presenting with COVID-19 to hospitals in North West London

Objectives

To describe the prevalence and nature of bacterial co-infections in COVID-19 patients within 48 hours of hospital admission and assess the appropriateness of empirical antibiotic treatment they received.

Methods

In this retrospective observational cohort study, we included all adult non-pregnant patients who were admitted to two acute hospitals in North West London in March and April 2020 and confirmed to have COVID-19 infection within 2 days of admission. Results of microbiological specimens taken within 48 hours of admission were reviewed and their clinical significance was assessed. Empirical antibiotic treatment of representative patients was reviewed. Patient age, gender, co-morbidities, inflammatory markers at admission, admission to ICU and 30 day all-cause in-hospital mortality were collected and compared between patients with and without bacterial co-infections.

Results

Of the 1396 COVID-19 patients included, 37 patients (2.7%) had clinically important bacterial co-infection within 48 hours of admission. The majority of patients (36/37 in those with co-infection and 98/100 in selected patients without co-infection) received empirical antibiotic treatment. There was no significant difference in age, gender, pre-existing illnesses, ICU admission or 30 day all-cause mortality in those with and without bacterial co-infection. However, white cell count, neutrophil count and CRP on admission were significantly higher in patients with bacterial co-infections.

Conclusions

We found that bacterial co-infection was infrequent in hospitalized COVID-19 patients within 48 hours of admission. These results suggest that empirical antimicrobial treatment may not be necessary in all patients presenting with COVID-19 infection, although the decision could be guided by high inflammatory markers.

Cross-sectional observational study of epidemiology of COVID-19 and clinical outcomes of hospitalised patients in North West London during March and April 2020

OBJECTIVE

The aim of this paper is to describe evolution, epidemiology and clinical outcomes of COVID-19 in subjects tested at or admitted to hospitals in North West London.

DESIGN

Observational cohort study.

SETTING

London North West Healthcare NHS Trust (LNWH).

PARTICIPANTS

Patients tested and/or admitted for COVID-19 at LNWH during March and April 2020 MAIN OUTCOME MEASURES: Descriptive and analytical epidemiology of demographic and clinical outcomes (intensive care unit (ICU) admission, mechanical ventilation and mortality) of those who tested positive for COVID-19.

RESULTS

The outbreak began in the first week of March 2020 and reached a peak by the end of March and first week of April. In the study period, 6183 tests were performed in on 4981 people. Of the 2086 laboratory confirmed COVID-19 cases, 1901 were admitted to hospital. Older age group, men and those of black or Asian minority ethnic (BAME) group were predominantly affected (p<0.05). These groups also had more severe infection resulting in ICU admission and need for mechanical ventilation (p<0.05). However, in a multivariate analysis, only increasing age was independently associated with increased risk of death (p<0.05). Mortality rate was 26.9% in hospitalised patients.

CONCLUSION

The findings confirm that men, BAME and older population were most commonly and severely affected groups. Only older age was independently associated with mortality.

Diagnosing pelvic osteomyelitis in patients with pressure ulcers: a systematic review comparing bone histology with alternative diagnostic modalities

Accurate diagnosis of osteomyelitis underlying pressure ulcers is essential, as overdiagnosis exposes patients to unnecessary and prolonged antibiotic therapy, while failure to diagnose prevents successful treatment. Histopathological examination of bone biopsy specimens is the diagnostic gold standard. Bone biopsy can be an invasive procedure, and, for this reason, other diagnostic modalities are commonly used. However, their accuracy is questioned in literature. This systematic review aims to assess accuracy of various modalities (clinical, microbiological and radiological) for the diagnosis of pelvic osteomyelitis in patients with pressure ulcers as compared to the gold standard. A systematic literature search was conducted in July 2019 using the MEDLINE (Medical Literature Analysis and Retrieval System - MEDLARS - Online) and CINAHL (Cumulative Index to Nursing and Allied Health Literature) databases. The search terms were "decubitus ulcer", "pressure ulcer", "pressure sore", "bedsore" and "osteomyelitis". The inclusion criteria were original full-text articles in English comparing the results of bone histology with those of other diagnostic modalities in adult patients with pelvic pressure ulcers. Six articles were included in the systematic review. Clinical diagnosis was found to be neither specific nor sensitive. Microbiological examination, and in particular cultures of bone biopsy specimens, displayed high sensitivity but low specificity, likely reflecting contamination. Radiological imaging in the form of X-ray and CT (computed tomography) scans displayed high specificity but low sensitivity. MRI (magnetic resonance imaging), bone scanning and indium-labelled scintigraphy displayed high sensitivity but low specificity. Our systematic review did not find any diagnostic method (clinical, microbiological or radiological) to be reliable in the diagnosis of pelvic osteomyelitis associated with pressure ulcers as compared to bone histology.

To screen or not to screen women for Group B Streptococcus (Streptococcus agalactiae) to prevent early onset sepsis in newborns: recent advances in the unresolved debate

Streptococcus agalactiae, also known as Group B streptococcus (GBS) is the commonest cause of early onset sepsis in newborns in developed high-income countries. Intrapartum antimicrobial (antibiotic) prophylaxis (IAP) is recognized to be highly effective in preventing early onset Group B sepsis (EOGBS) in newborns. The key controversy is about the strategy that should be used to identify mothers who should receive IAP. There are two strategies that are followed in developed countries: screening-based or risk-factor-based identification of women requiring IAP. The debate regarding which of the two approaches is better has intensified in the recent years with concerns about antimicrobial resistance, effect on newborn’s microbiome and other adverse effects. In this review, we have discussed some of the key research papers published in the period 2015–2019 that have addressed the relative merits and disadvantages of screening versus risk-factor-based identification of women requiring IAP. Although screening-based IAP appears to be more efficacious than risk-based IAP, IAP-based prevention has several limitations including ineffectiveness in prevention of late-onset GBS infection in babies, premature and still births, impact of IAP on neonatal microbiota, emergence of antimicrobial resistance and difficulties in implementing IAP-based strategies in middle and low income countries. Alternative strategies, principally maternal immunization against GBS would circumvent use of IAP. However, no licensed vaccines are currently available for use.

Pharmacokinetics/pharmacodynamics of antipseudomonal bacteriophage therapy in rats: a proof-of-concept study

OBJECTIVES

Pan-drug-resistant (PDR) Pseudomonas aeruginosa is one of the three top-priority pathogens identified by the WHO, and bacteriophages have been investigated as an alternative therapy. However, knowledge on the pharmacokinetics/pharmacodynamics (PK/PD) of phage therapy is sparse, limiting its clinical applications. This study aimed to evaluate the PK/PD of the antipseudomonal phage øPEV20 in vivo following intravenous administration.

METHODS

Healthy Sprague-Dawley rats were given øPEV20 as a single intravenous bolus of ~6, 9 and 11-log₁₀PFU/rat. Arterial blood was sampled over 72 h. At 72 h, the animals were killed and multiple tissues were harvested for biodistribution studies. A PK model was developed using the importance sampling algorithm and deterministic simulations with a PD model were performed.

RESULTS

A three-compartment model with non-linear clearance described the exposure of øPEV20 in blood. Model evaluation indicated that the model was robust and parameter estimates were accurate. The median (standard error) values of model-predicted PK parameters for V_C, V_P1, V_P2, Q₁, Q₂, V_m and K_m were 111 mL/rat (8.5%), 128 mL/rat (4.97%), 180 mL/rat (4.59%), 30.4 mL/h/rat (19.2%), 538 mL/h/rat (4.97%), 4.39 × 10¹⁰ PFU/h/rat (10.2%) and 1.64 × 10⁷ PFU/mL/rat (3.6%), respectively. The distribution of øPEV20 was not homogeneous; there was preferential accumulation in the liver and spleen. Deterministic simulations with a PD model confirmed the importance of the host immune system in facilitating phage-mediated bacterial elimination.

CONCLUSIONS

We developed a robust PK model to describe the disposition of phages in healthy rats. This model may have significant potential in facilitating future preclinical and clinical PK/PD investigations.

Is whole genome sequencing the answer for identifying Shigella bacteraemia?

We present a rare case of Shigella flexneri bacteraemia and the challenges of differentiating Escherichia coli and Shigella spp using conventional and newer laboratory techniques in diagnostic laboratories. The organism was identified only after whole genomic sequencing .

Clinical characteristics and treatment outcomes in a cohort of patients with pyogenic and amoebic liver abscess

Background

We describe the clinical features of a cohort of patients with liver abscesses and investigate relationships between clinical, radiological and microbiological findings and mortality.

Methods

Retrospective review of pyogenic (PLA) or amoebic liver abscesses (ALA) diagnosed and treated at a major infectious diseases department in London over 9 years.

Results

One hundred forty-one patient records were identified; 132 (93.6%) had PLA and 9 (6.4%) ALA. No organism was identified in 38.6% (51/132); a single bacterial species was isolated in 47.0% (62/132) of PLA, ≥ 2 in 14.4% (19/132). There was weak evidence of variation in abscess size by type of microorganism, with streptococcal PLA typically larger (p = 0.03 for Streptococcus milleri group, p = 0.05 for non-milleri streptococci). Patients with ALA were younger (median 41, IQR 37–51 years) than those with PLA (median 68, IQR 50.5–78 years) (p = 0.003) and all were male (9/9, 100%, (p = 0.03)), with a history of recent travel in the majority (6/9, 66.7% (p = 0.003)). C-reactive protein was higher in ALA than in PLA (p = 0.06). In the entire cohort, loculation (HR = 2.51 (95% CI 1.00–6.32), p = 0.04) and baseline ALP (HR = 4.78 (95% CI 1.19–19.2) per log₁₀ increase, p = 0.03) were associated with mortality. 16S ribosomal RNA (rRNA) analysis was used in a subset of culture-negative cases and increased the diagnostic yield by 13%.

Conclusions

Clinical or radiological features cannot be used to distinguish between PLA and ALA, or help identify the bacterial cause of PLA. However, ALA is more common in young, male patients with a history of travel. 16S rRNA analysis of abscess fluid has a role in improving microbiological diagnosis in culture-negative cases.

Electronic supplementary material

The online version of this article (10.1186/s12879-019-4127-8) contains supplementary material, which is available to authorized users.

Early-onset group B Streptococcus (EOGBS) infection subsequent to cessation of screening-based intrapartum prophylaxis: findings of an observational study in West London, UK

OBJECTIVES

To describe the impact on early-onset group B Streptococcus (EOGBS) infection rates following reversion from screening-based to risk-based intrapartum antimicrobial prophylaxis (IAP) for prevention.

SETTING

Maternity services provided by secondary healthcare organisation in North West London.

PARTICIPANTS

All women who gave birth in the healthcare organisation between April 2016 and March 2017. There were no exclusions.

DESIGN

Observational study comparing EOGBS rates in the postscreening period (2016-2017) with prescreening (2009-2013) and screening periods (2014-2015).

METHODS

Local guidelines for risk-based IAP were reintroduced in April 2016. Compliance with guidelines was audited. Gestational age, mode of delivery, maternal demographics and EOGBS rates in three time periods were compared using Poisson regression analysis. EOGBS was defined through GBS being cultured from blood, cerebrospinal fluid or other sterile fluids within 6 days of birth.

PRIMARY OUTCOME

EOGBS rates/1000 live births in prescreening, screening and postscreening periods RESULTS: Incremental changes in maternity population were observed throughout the study period (2009 onwards), in particular the ethnic profile of mothers. Of the 5033 live births in postscreening period, 9 babies developed EOGBS infection. Only one of the mothers of affected babies had a risk factor indicating use of IAP. Comparison of postscreening period with screening period showed a fivefold increase in EOGBS rates after adjustment for ethnicity (1.79 vs 0.33/1000 live births; risk ratio =5.67, p=0.009). There was no significant difference between prescreening and postscreening periods with rates of infection reverting to their prescreening level.

CONCLUSIONS

This study provides further evidence of efficacy of screening-based IAP compared with risk-based IAP in prevention of EOGBS in newborns in an area of high incidence.

Aplastic anemia and membranous nephropathy induced by intravenous mercury

Self-injection of mercury can be life-threatening. We report a case of attempted suicide by self-intravenous injection of elemental mercury. The patient suffered from two side effects : membranous nephropathy and aplastic anemia. She was treated and the systemic effects of mercury were reversed after 4 years. The toxicology of mercury, mechanisms of renal and systemic toxicities, and the various therapeutic measures for mercury poisoning are discussed.

Spinal stroke in older people secondary to dural arteriovenous fistula

A 61-year-old diabetic male developed weakness of both lower limbs while walking, 1 month go. When he was examined in hospital a hour later, it was found that he had total absence of movements in both legs, sensory loss of all modalities till umbilicus and had urinary retention. MRI spine demonstrated an intramedullary longitudinal T2 hyperintensity extending from upper thoracic cord till conus medullaris. A provisional diagnosis of transverse myelitis was made and started on corticosteroids. Partial improvement was noted over a 3 week period, after which he developed urinary infection, hyponatremia and sudden worsening of weakness. Repeat MRI spine with contrast raised the possibility of dural arteriovenous malformation leading to extensive spinal cord infarction, which was confirmed by MR angiogram.

Impact of guidelines and enhanced antibiotic stewardship on reducing broad-spectrum antibiotic usage and its effect on incidence of Clostridium difficile infection

OBJECTIVES

To evaluate the impact of an 'intervention' consisting of revised antibiotic guidelines for empirical treatment of common infections and enhanced stewardship on reducing broad-spectrum antibiotic usage and its effect on incidence of Clostridium difficile infection (CDI).

METHODS

This was a retrospective, quasi-experimental study using interrupted time series (ITS) over 12 months before and after the intervention. The setting was adult medical and surgical wards in University Hospital Lewisham, an acute general hospital in London. The intervention was introduced in April 2006. Revised guidelines avoided broad-spectrum antibiotics, e.g. fluoroquinolones, cephalosporins, clindamycin, amoxicillin and co-amoxiclav, as they were considered to be 'high risk' for CDI. Instead, 'low risk' antibiotics such as penicillin, clarithromycin, doxycycline, gentamicin, vancomycin, trimethoprim and nitrofurantoin were recommended. Changes in antibiotic usage and incidence of CDI before and after the intervention were compared using segmented regression analysis. The negative binomial model was used to analyse the time series to estimate the CDI incidence rate ratio (IRR) following the intervention.

RESULTS

The intervention was associated with a significant reduction in the use of fluoroquinolones by 105.33 defined daily doses (DDDs)/1000 occupied bed-days (OBDs) per month [95% confidence interval (CI) 34.18-176.48, P < 0.001] and cephalosporins by 45.93 DDDs/1000 OBDs/month (95% CI 24.11-67.74, P < 0.0001). There was no significant change in total antibiotic, clindamycin, amoxicillin or co-amoxiclav use. There was a significant decrease in CDI following the intervention [IRR 0.34 (0.20-0.58), P < 0.0001].

CONCLUSIONS

Revised antibiotic guidelines and enhanced stewardship was associated with a significant stepwise reduction in the use of cephalosporins and fluoroquinolones and a significant decrease in the incidence of CDI.

Risk factors for the spread of antibiotic-resistant bacteria

The emergence of antibiotic resistance is primarily due to excessive and often unnecessary use of antibiotics in humans and animals. Risk factors for the spread of resistant bacteria in hospitals and the community can be summarised as over-crowding, lapses in hygiene or poor infection control practices. Increasing antibiotic resistance in bacteria has been exacerbated by the slow pace in developing newer antibiotics. Methicillin-resistant Staphylococcus aureus (MRSA), vancomycin-resistant enterococci (VRE) and multiresistant Gram-negative bacteria are spread primarily by direct or indirect person-to-person contact. Independent risk factors for MRSA include the use of broad spectrum antibiotics, the presence of decubitus ulcers and prosthetic devices while those for VRE include prolonged hospitalisation and treatment with glycopeptides or broad spectrum antibiotics. For the spread of resistant Gram-negative bacteria risk factors include urinary catheterisation, excessive use of antibiotics and contamination of humidifiers and nebulisers. The spread of penicillin-resistant pneumococci (PRP) and drug-resistant and multidrug-resistant tuberculosis (MDRTb) is due to airborne transmission. Risk factors for the spread of PRP include overcrowding, tracheostomies and excessive use of penicillins for viral respiratory infections; for MDRTb they include poor compliance, convergence of immunosuppressed patients, delayed diagnosis or treatment, and poor or inadequate ventilation and isolation facilities. Recent developments in the genomic mapping of many bacteria and advances in combinatorial chemistry promise to usher in a new era of antibiotic development. While this may result in our regaining some of the ground lost to resistant bacteria, there will still be a continuing need to minimise the spread of antibiotic resistance through the rational use of antibiotic agents and stringent infection control practice.

Vancomycin-resistant gram-positive cocci: risk factors for faecal carriage

This case-control study was undertaken to identify the risk factors for the gastrointestinal carriage of vancomycin-resistant, Gram-positive cocci (VRGPC) including vancomycin-resistant enterococci (VRE). Use of oral vancomycin (P = 0.003) or cephalosporins (P = 0.03) and prolonged duration of stay in the hospital (P = 0.02) were found to be the significant risk factors. Other previously suggested risk factors such as location of the patients and presence of central venous or arterial lines were not significantly associated with carriage of VRGPC. Judicious usage of glycopeptides (particularly oral vancomycin) and cephalosporins is likely to be the most effective way to prevent and control the spread of VRGPC and VRE.

Selective medium for screening for vancomycin-resistant enterococci in faeces

Infections caused by vancomycin-resistant enterococci (VRE) are becoming increasingly prevalent throughout the world. Control measures include detection and isolation of carriers of VRE. A selective medium to detect faecal carriage of VRE is described. The medium has a high productivity ratio (90.4%) for VRE with VanA resistance phenotype, a moderate productivity ratio (79.2%) for VRE with VanB resistance phenotype, and a relatively low productivity ratio (65.5%) for VRE with VanC resistance phenotype. There was no breakthrough of vancomycin-susceptible enterococci. The medium selected the growth of all three types of VRE, which were used to spike faecal specimens. In a limited clinical trial, six faecal specimens of carriers and contacts were screened using the selective medium. Vancomycin-resistant enterococci (Enterococcus faecalis, VanA phenotype) were detected in four of the specimens. In all four specimens the growth of VRE was nearly pure and easily identifiable.

Control of outbreaks of viral diarrhoea in hospitals--a practical approach

Outbreaks of viral diarrhoea are common in hospitals, particularly in the geriatric and children's wards. Person-to-person spread is the most frequent mode of transmission of infection. Establishment of alerting mechanisms, liaison with laboratories with electron microscopy facilities for making the diagnosis, isolation of patients, use of appropriate disinfectants and maintaining good lines of communication are all important for successful control of these outbreaks.

Conventional screening for enteropathogenic Escherichia coli in the UK. Is it appropriate or necessary?

Enteropathogenic Escherichia coli (EPEC) is a well-recognized cause of infantile diarrhoea in the developing countries. In the developed countries, however, the incidence of EPEC associated outbreaks has dramatically declined. The last major outbreak in the UK was reported in 1980. This paper reviews the recent advances in the field of pathogenesis of diarrhoea caused by EPEC and questions the need to screen routinely for EPEC by conventional serological methods used in clinical microbiology laboratories in the UK.

A review of hospitalized patients with bacterial gastroenteritis

The distribution and clinical management of thirty-two hospitalized patients with salmonella and campylobacter infections were reviewed and the impact of these infections on hospital resources was assessed. Eighteen patients with salmonella infection had an age and sex distribution comparable with the community cases. In contrast, 10 out of 14 (71.4%) patients with campylobacter infection were under 20 years of age though the peak incidence of the infection in the community occurred in the 21-65 years age group (67%). There was no male predominance. The median duration of stay in hospital was 6 days for patients with salmonella infection and 3 days for those with campylobacter infection. Physicians were inconsistent in the treatment of campylobacter infection. Overall the financial impact of managing patients with salmonella and campylobacter infection was considerable (1384 pounds and 779 pounds respectively per patient). A limitation on unnecessarily prolonged hospital stays and the establishment of clear guidelines for the clinical management of these infections are necessary.

Ciprofloxacin as a cause of Clostridium difficile-associated diarrhoea in an HIV antibody-positive patient

Ciprofloxacin is an uncommon cause of pseudomembranous colitis. A case is described in which diarrhoea was associated with the presence of clostridial toxin in an HIV-infected patient and the possible implications are discussed.

Bladder irrigation or irritation?

Exfoliation rates of urothelial cells following bladder irrigation were studied in patients with long-term indwelling catheters and chronic urinary tract infections (UTI). The irrigations were associated with an increased shedding of urothelial cells. Ultrastructural studies of these cells demonstrated increased disruption when compared with those obtained from normal subjects without catheters or chronic infection. The findings suggest that bladder irrigation further damages the already disrupted urothelium, which may in turn increase the predisposition of the bladder to the recurrent infections, commonly associated with patients who have indwelling urinary catheters. Bladder irrigation methods and the indications for their use require reassessment.

Routine cleaning and the elimination of Campylobacter pylori from endoscopic biopsy forceps

The effect of routine cleaning in removing Campylobacter pylori from the biopsy forceps of endoscopes has been examined in a series of 50 patients. Campylobacter pylori was isolated from the biopsies of 15 of the patients, while one of the 50 biopsy forceps washings yielded the organism after routine cleaning. This study suggests that there is a small chance of transmitting C. pylori by endoscopic equipment if cleaning is the only method of decontamination adopted.