Evaluation of a pharmacist-led penicillin allergy de-labelling ward round: a novel antimicrobial stewardship intervention

BACKGROUND

Antibiotic allergy labels (AALs), reported by up to 25% of hospitalized patients, are a significant barrier to appropriate prescribing and a focus of antimicrobial stewardship (AMS) programmes.

METHODS

A prospective audit of a pharmacist-led AMS penicillin allergy de-labelling ward round at Austin Health (Melbourne, Australia) was evaluated. Eligible inpatients with a documented penicillin allergy receiving an antibiotic were identified via an electronic medical report and then reviewed by a pharmacist-led AMS team. The audit outcomes evaluated were: (i) AMS post-prescription review recommendations; (ii) direct de-labelling; (iii) inpatient oral rechallenge referral; (iv) skin prick testing/intradermal testing referral; and (v) outpatient antibiotic allergy clinic assessment.

RESULTS

Across a 5 month period, 106 patients were identified from a real-time electronic prescribing antibiotic allergy report. The highest rate of penicillin allergy de-labelling was demonstrated in patients who were referred for an inpatient oral rechallenge with 95.2% (n = 21) successfully having their penicillin AAL removed. From the 22 patients with Type A reactions, 63.6% had their penicillin AAL removed. We demonstrated a significant decrease in the prescribing of restricted antibiotics (defined as third- or fourth-generation cephalosporins, fluoroquinolones, glycopeptides, carbapenems, piperacillin/tazobactam, lincosamides, linezolid or daptomycin) in patients reviewed (pre 42.5% versus post 17.9%, P = 0.0002).

CONCLUSIONS

A pharmacist-led AMS penicillin allergy de-labelling ward round reduced penicillin AALs and the prescribing of restricted antibiotics. This model could be implemented at other hospitals with existing AMS programmes.

Antimicrobial allergy 'labels' drive inappropriate antimicrobial prescribing: lessons for stewardship

BACKGROUND

The presence of antimicrobial allergy designations ('labels') often substantially reduces prescribing options for affected patients, but the frequency, accuracy and impacts of such labels are unknown.

METHODS

The National Antimicrobial Prescribing Survey (NAPS) is an annual de-identified point prevalence audit of Australian inpatient antimicrobial prescribing using standardized definitions of guideline compliance, appropriateness and indications. Data were extracted for 2 years (2013-14) and compared for patients with an antimicrobial allergy label (AAL) and with no AAL (NAAL).

RESULTS

Among 21 031 patients receiving antimicrobials (33 421 prescriptions), an AAL was recorded in 18%, with inappropriate antimicrobial use significantly higher in the AAL group versus the NAAL group (OR 1.12, 95% CI 1.05-1.22, P < 0.002). Patterns of antimicrobial use were significantly influenced by AAL, with lower β-lactam use (AAL versus NAAL; OR 0.47, 95% CI 0.43-0.50, P < 0.001) and higher quinolone (OR 2.07, 95% CI 1.83-2.34, P < 0.0001), glycopeptide (OR 1.59, 95% CI 1.38-1.83, P < 0.0001) and carbapenem (OR 1.74, 95% CI 1.43-2.13, P < 0.0001) use. In particular, among immunocompromised patients, AAL was associated with increased rates of inappropriate antimicrobial use (OR 1.68, 95% CI 1.21-2.30, P = 0.003), as well as increased use of quinolones (OR 1.88, 95% CI 1.16-3.03, P = 0.02) and glycopeptides (OR 1.82, 95% CI 1.17-2.84, P = 0.01).

CONCLUSIONS

AALs are common and appear to be associated with higher rates of inappropriate prescribing and increased use of broad-spectrum antimicrobials. Improved accuracy in defining AALs is likely to be important for effective antimicrobial stewardship (AMS), with efforts to 'de-label' inappropriate AAL patients a worthwhile feature of future AMS initiatives.

Acute Flaccid Paralysis: The New, The Old, and The Preventable

Acute flaccid paralysis (AFP) has a changing epidemiology with ongoing polio outbreaks and emerging causes such as nonpolio enteroviruses and West Nile virus (WNV). We report a case of AFP from the Horn of Africa that was initially classified as probable polio but subsequently found to be due to WNV.

Is fosfomycin a potential treatment alternative for multidrug-resistant gram-negative prostatitis?

BACKGROUND

Multidrug-resistant gram-negative bacterial (MDR-GNB) infections of the prostate are an increasing problem worldwide, particularly complicating transrectal ultrasound (TRUS)-guided prostate biopsy. Fluoroquinolone-based regimens, once the mainstay of many protocols, are increasingly ineffective. Fosfomycin has reasonable in vitro and urinary activity (minimum inhibitory concentration breakpoint ≤64 µg/mL) against MDR-GNB, but its prostatic penetration has been uncertain, so it has not been widely recommended for the prophylaxis or treatment of MDR-GNB prostatitis.

METHODS

In a prospective study of healthy men undergoing a transurethral resection of the prostate for benign prostatic hyperplasia, we assessed serum, urine, and prostatic tissue (transition zone [TZ] and peripheral zone [PZ]) fosfomycin concentrations using liquid chromatography-tandem mass spectrometry, following a single 3-g oral fosfomycin dose within 17 hours of surgery.

RESULTS

Among the 26 participants, mean plasma and urinary fosfomycin levels were 11.4 ± 7.6 µg/mL and 571 ± 418 µg/mL, 565 ± 149 minutes and 581 ± 150 minutes postdose, respectively. Mean overall prostate fosfomycin levels were 6.5 ± 4.9 µg/g (range, 0.7-22.1 µg/g), with therapeutic concentrations detectable up to 17 hours following the dose. The mean prostate to plasma ratio was 0.67 ± 0.57. Mean concentrations within the TZ vs PZ prostate regions varied significantly (TZ, 8.3 ± 6.6 vs PZ, 4.4 ± 4.1 µg/g; P = .001). Only 1 patient had a mean prostatic fosfomycin concentration of <1 µg/g, whereas the majority (70%) had concentrations ≥4 µg/g.

CONCLUSIONS

Fosfomycin appears to achieve reasonable intraprostatic concentrations in uninflamed prostate following a single 3-g oral dose, such that it may be a potential option for prophylaxis pre-TRUS prostate biopsy and possibly for the treatment of MDR-GNB prostatitis. Formal clinical studies are now required.

Enterococcal bacteraemia: factors influencing mortality, length of stay and costs of hospitalization

Enterococci are a major cause of nosocomial bacteraemia. The impacts of vanB vancomycin resistance and antibiotic therapy on outcomes in enterococcal bacteraemia are unclear. Factors that affect length of stay (LOS) and costs of managing patients with enterococcal bacteraemia are also unknown. This study aimed to identify factors associated with mortality, LOS and hospitalization costs in patients with enterococcal bacteraemia and the impact of vancomycin resistance and antibiotic therapy on these outcomes. Data from 116 patients with vancomycin-resistant Enterococci (VRE), matched 1:1 with patients with vancomycin-susceptible Enterococcus (VSE), from two Australian hospitals were reviewed for clinical and economic outcomes. Univariable and multivariable logistic and quantile regression analyses identified factors associated with mortality, LOS and costs. Intensive care unit admission (OR, 8.57; 95% CI, 3.99-18.38), a higher burden of co-morbidities (OR, 4.55; 95% CI, 1.83-11.33) and longer time to appropriate antibiotics (OR, 1.02; 95% CI, 1.01-1.03) were significantly associated with mortality in enterococcal bacteraemia. VanB vancomycin resistance increased LOS (4.89 days; 95% CI, 0.56-11.52) and hospitalization costs (AU$ 28 872; 95% CI, 734-70 667), after adjustment for confounders. Notably, linezolid definitive therapy was associated with lower mortality (OR, 0.13; 95% CI, 0.03-0.58) in vanB VRE bacteraemia patients. In patients with VSE bacteraemia, time to appropriate antibiotics independently influenced mortality, LOS and hospitalization costs, and underlying co-morbidities were associated with mortality. The study findings highlight the importance of preventing VRE bacteraemia and the significance of time to appropriate antibiotics in the management of enterococcal bacteraemia.

Significant reduction in vancomycin-resistant enterococcus colonization and bacteraemia after introduction of a bleach-based cleaning-disinfection programme

BACKGROUND

Vancomycin-resistant enterococcus (VRE) colonization and infection have increased at our hospital, despite adherence to standard VRE control guidelines.

AIM

We implemented a multi-modal, hospital-wide improvement programme including a bleach-based cleaning-disinfection programme ('Bleach-Clean'). VRE colonization, infection and environmental contamination were compared pre and post implementation.

METHODS

The programme included a new product (sodium hypochlorite 1000 ppm + detergent), standardized cleaning-disinfection practices, employment of cleaning supervisors, and modified protocols to rely on alcohol-based hand hygiene and sleeveless aprons instead of long-sleeved gowns and gloves. VRE was isolated using chromogenic agar and/or routine laboratory methods. Outcomes were assessed during the 6 months pre and 12 months post implementation, including proportions (per 100 patients screened) of VRE colonization in high-risk wards (HRWs: intensive care, liver transplant, renal, haematology/oncology); proportions of environmental contamination; and episodes of VRE bacteraemia throughout the entire hospital.

FINDINGS

Significant reductions in newly recognized VRE colonizations (208/1948 patients screened vs 324/4035, a 24.8% reduction, P = 0.001) and environmental contamination (66.4% reduction, P = 0.012) were observed, but the proportion of patients colonized on admission was stable. The total burden of inpatients with VRE in the HRWs also declined (median percentage of colonized inpatients per week, 19.4% vs 17.3%, P = 0.016). Hospital-wide VRE bacteraemia declined from 14/2935 patients investigated to 5/6194 (83.1% reduction; P < 0.001), but there was no change in vancomycin-susceptible enterococcal bacteraemia (P = 0.54).

CONCLUSION

The Bleach-Clean programme was associated with marked reductions in new VRE colonizations in high-risk patients, and VRE bacteraemia across the entire hospital. These findings have important implications for VRE control in endemic healthcare settings.

Doxycycline vs. macrolides in combination therapy for treatment of community-acquired pneumonia

We assessed the comparative efficacy of empirical therapy with beta-lactam plus macrolide vs. beta-lactam plus doxycycline for the treatment of community-acquired pneumonia (CAP) among patients in the Australian Community-Acquired Pneumonia Study. Both regimens demonstrated similar outcomes against CAP due to either 'atypical' (Chlamydophila, Legionella or Mycoplasma spp.) or typical bacterial pathogens.

Association between severe pandemic 2009 influenza A (H1N1) virus infection and immunoglobulin G(2) subclass deficiency

BACKGROUND

. Severe pandemic 2009 influenza A virus (H1N1) infection is associated with risk factors that include pregnancy, obesity, and immunosuppression. After identification of immunoglobulin G(2) (IgG(2)) deficiency in 1 severe case, we assessed IgG subclass levels in a cohort of patients with H1N1 infection.

METHODS

Patient features, including levels of serum IgG and IgG subclasses, were assessed in patients with acute severe H1N1 infection (defined as infection requiring respiratory support in an intensive care unit), patients with moderate H1N1 infection (defined as inpatients not hospitalized in an intensive care unit), and a random sample of healthy pregnant women.

RESULTS

Among the 39 patients with H1N1 infection (19 with severe infection, 7 of whom were pregnant; 20 with moderate infection, 2 of whom were pregnant), hypoabuminemia (P < .001), anemia (P < .001), and low levels of total IgG (P= .01), IgG(1) (P= .022), and IgG(2) (15 of 19 vs 5 of 20; P= .001; mean value +/- standard deviation [SD], 1.8 +/- 1.7 g/L vs 3.4 +/- 1.4 g/L; P= .003) were all statistically significantly associated with severe H1N1 infection, but only hypoalbuminemia (P= .02) and low mean IgG(2) levels (P= .043) remained significant after multivariate analysis. Follow-up of 15 (79%) surviving IgG(2)-deficient patients at a mean (+/- SD) of 90 +/- 23 days (R, 38-126) after the initial acute specimen was obtained found that hypoalbuminemia had resolved in most cases, but 11 (73%) of 15 patients remained IgG(2) deficient. Among 17 healthy pregnant control subjects, mildly low IgG(1) and/or IgG(2) levels were noted in 10, but pregnant patients with H1N1 infection had significantly lower levels of IgG(2) (P= .001).

CONCLUSIONS

Severe H1N1 infection is associated with IgG(2) deficiency, which appears to persist in a majority of patients. Pregnancy-related reductions in IgG(2) level may explain the increased severity of H1N1 infection in some but not all pregnant patients. The role of IgG(2) deficiency in the pathogenesis of H1N1 infection requires further investigation, because it may have therapeutic implications.

A quantitative assessment of the efficacy of surgical and N95 masks to filter influenza virus in patients with acute influenza infection

We assessed the in vivo efficacy of surgical and N95 (respirator) masks to filter reverse transcription-polymerase chain reaction (RT-PCR)-detectable virus when worn correctly by patients with laboratory-confirmed acute influenza. Of 26 patients with a clinical diagnosis of influenza, 19 had the diagnosis confirmed by RT-PCR, and 9 went on to complete the study. Surgical and N95 masks were equally effective in preventing the spread of PCR-detectable influenza.

Clostridium lavalense sp. nov., a glycopeptide-resistant species isolated from human faeces

Two vancomycin-resistant, strictly anaerobic, Gram-positive, rod-shaped, spore-forming organisms (strains CCRI-9842(T) and CCRI-9929) isolated from human faecal specimens in Québec, Canada, and Australia were characterized using phenotypic, biochemical and molecular taxonomic methods. Pairwise analysis of the 16S rRNA gene sequences showed that both strains were closely related to each other genetically (displaying 99.2 % sequence similarity) and represented a previously unknown subline within the Clostridium coccoides rRNA group of organisms (rRNA cluster XIVa of the genus Clostridium). Strains CCRI-9842(T) and CCRI-9929 used carbohydrates as fermentable substrates, producing acetic acid as the major product of glucose metabolism. The novel strains were most closely related to Clostridium asparagiforme, Clostridium bolteae and Clostridium clostridioforme, but morphological, biochemical and phylogenetic studies demonstrated that they represent a previously unidentified species of the genus Clostridium. This was confirmed by the unique cellular fatty acid composition of strains CCRI-9842(T) and CCRI-9929. Therefore, on the basis of data from the polyphasic taxonomic analysis, it is proposed that strains CCRI-9842(T) and CCRI-9929 represent a novel species of the genus Clostridium, for which the name Clostridium lavalense sp. nov. is proposed. The type strain is CCRI-9842(T) (=CCUG 54291(T)=JCM 14986(T)=NML 03-A-015(T)).

The etiology of community-acquired pneumonia in Australia: why penicillin plus doxycycline or a macrolide is the most appropriate therapy

BACKGROUND

Available data on the etiology of community-acquired pneumonia (CAP) in Australia are very limited. Local treatment guidelines promote the use of combination therapy with agents such as penicillin or amoxycillin combined with either doxycycline or a macrolide.

METHODS

The Australian CAP Study (ACAPS) was a prospective, multicenter study of 885 episodes of CAP in which all patients underwent detailed assessment for bacterial and viral pathogens (cultures, urinary antigen testing, serological methods, and polymerase chain reaction). Antibiotic agents and relevant clinical outcomes were recorded.

RESULTS

The etiology was identified in 404 (45.6%) of 885 episodes, with the most frequent causes being Streptococcus pneumoniae (14%), Mycoplasma pneumoniae (9%), and respiratory viruses (15%; influenza, picornavirus, respiratory syncytial virus, parainfluenza virus, and adenovirus). Antibiotic-resistant pathogens were rare: only 5.4% of patients had an infection for which therapy with penicillin plus doxycycline would potentially fail. Concordance with local antibiotic recommendations was high (82.4%), with the most commonly prescribed regimens being a penicillin plus either doxycycline or a macrolide (55.8%) or ceftriaxone plus either doxycycline or a macrolide (36.8%). The 30-day mortality rate was 5.6% (50 of 885 episodes), and mechanical ventilation or vasopressor support were required in 94 episodes (10.6%). Outcomes were not compromised by receipt of narrower-spectrum beta-lactams, and they did not differ on the basis of whether a pathogen was identified.

CONCLUSIONS

The vast majority of patients with CAP can be treated successfully with narrow-spectrum beta-lactam treatment, such as penicillin combined with doxycycline or a macrolide. Greater use of such therapy could potentially reduce the emergence of antibiotic resistance among common bacterial pathogens.