Rapid screening and early precautions for carbapenem-resistant Acinetobacter baumanniicarriers decreased nosocomial transmission in hospital settings: a quasi-experimental study

Norihisa Yamamoto,
Shigeto Hamaguchi,
Yukihiro AkedaEmail author,
Pitak Santanirand,
Narong Chaihongsa,
Suntariya Sirichot,
Suwichak Chiaranaicharoen,
Hideharu Hagiya,
Kouji Yamamoto,
Anusak Kerdsin,
Kazuhisa Okada,
Hisao Yoshida,
Shigeyuki Hamada,
Kazunori Oishi,
Kumthorn Malathum and
Kazunori Tomono

Antimicrobial Resistance & Infection Control20198:110

https://doi.org/10.1186/s13756-019-0564-9

Received: 30 January 2019
Accepted: 18 June 2019
Published: 27 June 2019

Abstract

Background

Active surveillance has the potential to prevent nosocomial transmission of carbapenem-resistant Acinetobacter baumannii (CRAB). We assessed whether rapid diagnosis using clinical specimen-direct loop-mediated isothermal amplification (LAMP), a rapid molecular diagnostic assay, and subsequent intervention, could reduce CRAB nosocomial transmission in intensive care units (ICUs).

Methods

A before and after (quasi-experimental) study was conducted in two ICUs at the Mahidol University Faculty of Medicine Ramathibodi Hospital with 3 months of observational period followed by 9 months of interventional period. All patients were screened for CRAB using both the culture and LAMP method from rectal swab and/or bronchial aspirates (intubated patients only) upon admission, weekly thereafter, and upon discharge. During the pre-intervention period, we performed contact precautions based on culture results. In contrast, during the intervention period, we initiated contact precautions within a few hours after sample collection on the basis of LAMP results.

Results

A total of 1335 patients were admitted to the ICUs, of which 866 patients (pre-intervention period: 187; intervention period: 679) were eligible for this study. Incidence rate of CRAB infection decreased to 20.9 per 1000 patient-days in the intervention period from 35.2 in the pre-intervention period (P < 0.02). The calculated hazard ratio of CRAB transmission was 0.65 (95% confidence interval [CI], 0.44–0.97). Risk factors for CRAB acquisition included exposure to carbapenem (hazard ratio, 2.54 [95% CI: 1.61–5.57]).

Conclusions

LAMP screening for CRAB upon ICU admission proved feasible for routine clinical practice. Rapid screening using LAMP followed by early intervention may reduce CRAB transmission rates in ICUs when compared to conventional intervention.