Mycobacterium abscessus - an uncommon, but important cause of peritoneal dialysis-associated peritonitis - case report and literature review.

BACKGROUND: Peritoneal dialysis (PD) is a form of therapy for end-stage kidney disease (ESKD), and peritonitis is a known complication. Mycobacterium (M) species associated peritonitis in PD patients is uncommon. Our experience of managing PD associated peritonitis caused by M abscessus in a middle-aged man with ESKD due to focal segmental glomerulosclerosis is shared in this article with a review of the literature on this condition. CASE PRESENTATION: A 49-year old man presented to our unit with symptoms of peritonitis and cloudy PD effluent. Initial analysis of PD fluid showed Gram stain was negative, with no organism grown. Empirical PD peritonitis treatment with intra-peritoneal antibiotics did not improve his symptoms and he required intravenous antibiotics, PD catheter removal and a switch to haemodialysis. Cultures of the PD fluid later grew M abscessus, and the antibiotic regimen was changed appropriately, leading to clinical improvement. CONCLUSION: M abscessus associated peritonitis in PD patients is rare. It needs to be borne in mind when clinical improvement is not seen with standard broad-spectrum antibiotics, especially in situations where the PD fluid is initially deemed to be culture negative. PD fluid samples should be sent for acid-fast bacillus and if detected, should be further analysed with genome-wide sequencing to confirm the species of the Mycobacterium. Prompt removal of the catheter with peritoneal washout is critical for clinical improvement.

What are the critical steps in processing blood cultures? A prospective audit evaluating current practice of reporting blood cultures in a centralised laboratory serving secondary care hospitals.

AIMS: To assess current procedures of processing positive blood cultures against national standards with an aim to evaluate its clinical impact and to determine the utility of currently available rapid identification and susceptibility tests in processing of blood cultures. METHODS: Blood cultures from three secondary care hospitals, processed at a centralised laboratory, were prospectively audited. Data regarding processing times, communication with prescribers, changes to patient management and mortality within 30 days of a significant blood culture were collected in a preplanned pro forma for a 4-week period. RESULTS: Of 2206 blood cultures, 211 positive blood cultures flagged positive. Sixty-nine (3.1%) of all cultures were considered to be contaminated. Fifty per cent of blood cultures that flagged positive had a Gram stain reported within 2 hours. Two (0.99%) patients with a significant bacteraemia had escalation of antimicrobial treatment at the point of reporting the Gram stain that was subsequently deemed necessary once sensitivity results were known. Most common intervention was de-escalation of therapy for Gram-positive organisms at the point of availability of pathogen identification (25.6% in Gram positive vs 10% in Gram negative; p=0.012). For Gram-negative organisms, the most common intervention was de-escalation of therapy at the point of availability of sensitivity results (43% in Gram negatives vs 17.9% in Gram positive; p=0.0097). Overall mortality within 30 days of a positive blood culture was 10.9% (23/211). Antibiotic resistance may have contributed to mortality in four of these patients (three Gram negative and one Gram positive). CONCLUSION: Gram stain result had the least impact on antibiotic treatment interventions (escalation or de-escalation). Tests that improve identification time for Gram-positive pathogens and sensitivity time for Gram-negative pathogens had the greatest impact in making significant changes to antimicrobial treatment.

Epidemiology, antibiotic resistance trends and the cost of enteric fever in East London, 2005-2010.

INTRODUCTION: Enteric fever seen in the UK has usually been acquired abroad. The cost to the NHS of treating enteric fever cases is not known. Data on the epidemiology of enteric fever, inpatient treatment costs and the public health management is needed to make decisions regarding the cost benefit considerations of introducing targeted prevention strategies. METHODS: A retrospective study of laboratory confirmed enteric fever cases was conducted to estimate the cost of inpatient treatment and to determine antimicrobial resistance patterns at two hospitals in East London between January 2005 and the end of August 2010. RESULTS: 138 cases of enteric fever were identified during the study period (90 S.ser.Typhi and 48 S. ser. Paratyphi). 92% had a recent history of foreign travel, 57% had travelled to visit friends and relatives (VFRs), 26% sought pre-travel health advice and 26% of patients had received typhoid vaccination. The inpatient treatment cost of 138 cases to the NHS was £272,747. The proportion of isolates with high level ciprofloxacin resistance (MICs>1 mg/L) has increased from 10% in 2006 to 30% in 2010. Our data also shows the emergence of isolates with high azithromycin MICs (>32 mg/L); 60% (six out of ten) isolates tested in July-August 2010. CONCLUSIONS: There is a significant direct cost of treating enteric fever cases on the NHS. Cost reduction measures are confined due to the lack of effective oral antibiotics following the emergence of high level resistance to ciprofloxacin and azithromycin. Outpatient parenteral antibiotic therapy service and improved preventative public health measures aimed at VFR travellers in particular may be helpful in reducing costs.