Contamination level of transvaginal ultrasound probes in standard setting: A meta-analysis

Abstract

Gynecologist should be aware of cross infection using transvaginal ultrasonography. In fact, the contamination was usually being underestimated. Disinfection and probe cover in transvaginal ultrasound remained controversial. This study was planned with the objective to review the pooled proportion of contamination and types of microbes contaminated after the standard procedure at transvaginal probe and characterize the methods of disinfection and type of cover probe used in transvaginal ultrasound. Comprehensive literature search was done in Medline (1966-2015), SCOPUS (2004-2015), EMBASE, and Cochrane Central Register of Controlled Trials along with reference lists of electronically retrieved studies. We considered all published English language articles. The author used search strategy with words such as transvaginal, ultrasound, probe, contamination, and infect. Full-text journals are more preferred, but the abstract only journal is considered based on if the data are provided in the abstract. Data of study design, contamination rate, ultrasound disinfection technique, and probe cover were being reviewed. The pooled proportion of microbes contamination and difference of disinfection and probe cover were determined using Stata 12 and Review Manager 5.4. From 110 studies, 13 studies were potentially eligible for systematic review. Pooled proportion of total microbes contamination was 31% (95% CI: 1-56%, I2: 99.14%, P = 0.00). This rate was found 50% in bacteria contamination and only 4% in virus contamination. The most prevalence bacteria were coagulase-negative Staphylococci. A similar contamination rate was found either using condom or specific cover as probe cover (both 3%, risk difference −0.04). Interestingly, some studies showed advantage of using gloves as probe covers and automated disinfectant machine as disinfection methods. Contamination rate, especially bacteria contamination, is still high even after using the standard disinfection procedure. Further research is needed to find new disinfection procedures to reduce the contamination rate.