Mortality attributable to hospital acquired infections with multidrug-resistant bacteria in a large group of German hospitals.

Background: According to extrapolations, around 35,000 patients in Germany develop hospital acquired infections (HAI) with a multidrug-resistant organism (MDRO) every year, and about 1500 of them die. Previous estimations were based on laboratory data and prevalence studies. Aim of this study was to establish the incidences of hospital acquired MDRO infections and the resulting deaths by expert review.

Methods: Data on patients suffering from a hospital acquired MDRO infection were collected from 32 hospitals from all care levels. Records of patients with MDRO infection who died in the year 2016 underwent an onsite review by two experts to determine the impact of the infection, if any, on the cause of death.

Results: A total of 714,108 in-patients were treated in 32 hospitals participating in the study. Of these patients, 1136 suffered a hospital acquired MDRO infection (1.59 per 1000 patients). 215 patients with an MDRO infection died [0.301 per 1000, (95% CI 0,261-0,341)], but only in 78 cases this was estimated as the cause of death [0.109 per 1000 patients (95% CI 0.085-0.133)].

Conclusion: By putting the above rates in relation to the total number of in-patients in Germany, it can be rated that around 31,052 patients per year suffer a hospital acquired MDRO infection, and 2132 patients die from it. These results from our reviewer investigation confirm earlier extrapolations.