The Impact of an Infectious Diseases Consultation on Antimicrobial Prescribing

To the Editors: The article published in the April issue by Gwee et al1 describes the activities of an infectious diseases (ID) consult service in children. Their study did not aim to compare patients who received a consult with those who did not. Using national Australian data, we have compared patients who received a consult with those who did not, to provide additional insight to the value of ID consultation in improving antimicrobial use. In conjunction with the international Antimicrobial Resistance and Prescribing in European Children study,2 8 Australian pediatric hospitals participated in a single-day, hospital-wide point prevalence survey of antimicrobials. Deidentified data were collected about all antimicrobial prescriptions, including the appropriateness of the antimicrobial prescription using a standardized method of describing inappropriate prescribing (decision, choice and application) and whether there had been a concurrent ID consult. Of 1373 patients, 631 (46%) were receiving 1174 antimicrobials. Of this group, 153 (27%) patients had had an ID consult involving 255 (22%) prescriptions. There were 919 (78%) prescriptions not subject to ID consultation and 3 (0.4%) were unknown. Of the 255 antimicrobial prescriptions where an ID consult had occurred, 99 (39%) were from high-intensity units, with consults accounting for 52/235 (22%) of antimicrobial prescriptions in hematology/oncology, 23/78 (28%) in pediatric intensive care unit and 26/222 (12%) in neonates. Gwee et al1 reported lower proportions of ID consults in these units, likely because that study included patients not receiving antimicrobials. A comparison of antimicrobial prescriptions was made between patients who did and did not have an ID consult using a χ2 test (Table 1). Prescriptions guided by ID consultation were significantly more likely than those with no consult to be for treatment of community- or hospital-acquired infection. ID consultation was less likely to be associated with medical and surgical prophylaxis, which is often based on protocols. Targeted treatment for proven infection was significantly more likely to have been guided by an ID consult, and consultation was less likely for use of empiric therapy, reflecting that 7 of the 8 hospitals had guidelines for empiric antibiotics for common infections.3TABLE 1: Comparison of Antimicrobial Prescriptions With and Without an ID ConsultFor specific antibacterial agents, there was no universal association between spectrum of antibiotic activity and involvement of an ID consult. Antimicrobials least likely to have involved ID consultation were those incorporated in protocols for prophylaxis (eg, first-generation cephalosporins) or empiric treatment (eg, aminoglycosides). Antimicrobials most likely to have involved ID consultation were those restricted by antimicrobial stewardship programs (eg, carbapenems). Although some broader spectrum antibiotics were associated with ID consultation, a limitation of our data is the inability to determine confounders, for example, patient complexity. Antimicrobials subject to ID consultation were more likely to have a reason documented for their use. Inappropriate prescribing was significantly more common where there was no ID consult, most frequently in relation to decision making concerning the need for antimicrobials at all. Inappropriate choice of agents and their application (dose, frequency, route) were also more common when there was no ID consult, although numbers were low, perhaps reflecting the impact of guidelines. In an era when antimicrobial stewardship is of critical importance, our data provide important evidence for the value of an ID consult in ensuring targeted and appropriate use of antibiotics. We would like to acknowledge the physicians and pharmacists, including Maria Chan, Mona Mostaghim and James Newcombe, at every participating hospital who were involved in collecting the data. Joshua Osowicki, MB BS Amanda Gwee, MB BS Infectious Diseases Unit Department of General Medicine The Royal Children’s Hospital Melbourne Parkville Jesuina Noronha, MB BS Department of Paediatric Infectious Diseases Monash Children’s, Clayton Pamela Palasanthiran, MD Brendan McMullan, MB BS Department of Immunology and Infectious Diseases Sydney Children’s Hospital, Randwick School of Women’s and Children's Health University of New South Wales New South Wales Philip N. Britton, MB BS David Isaacs, MD Department of Infectious Diseases and Microbiology Tony Lai, B Pharm Pharmacy Department The Children’s Hospital at Westmead Westmead, New South Wales Clare Nourse, MD Paediatric Infection Management Service Mater Health Services Department of Paediatrics University of Queensland Minyon Avent, Pharm D Mater Pharmacy Services Mater Health University of Queensland Centre for Clinical Research South Brisbane Paul Moriarty, MB BS Paediatric Infection Management Service Mater Health Services South Brisbane Julia Clark, MB BS Infection Management and Prevention Service Royal Children’s Hospital, Brisbane, Queensland Joshua R. Francis, MB BS Department of Paediatric and Adolescent Medicine Princess Margaret Hospital for Children Subiaco Christopher C. Blyth, MB BS Department of Paediatric and Adolescent Medicine Princess Margaret Hospital for Children, Subiaco School of Paediatrics and Children’s Health University of Western Australia PathWest Laboratory Medicine WA Princess Margaret Hospital, Western Australia Celia M. Cooper, BMBS SA Pathology, Women’s and Children’s Hospital North Adelaide, South Australia Penelope A Bryant, PhD Infectious Diseases Unit Department of General Medicine The Royal Children’s Hospital Melbourne Murdoch Children’s Research Institute, Parkville Department of Paediatric Infectious Diseases Monash Children’s Clayton, Australia on behalf of the ANZPID-ASAP Group Australian and New Zealand Paediatric Infectious Diseases Australasian Stewardship of Antimicrobials in Paediatrics