Key points

The National Reference Laboratory for C. difficile

• The National Reference Laboratory coordinates a sentinel surveillance program with 22 participating acute care hospitals in the Netherlands, and performs molecular characterisation of C. difficile in cases of severe C. difficile infections (CDI) or suspected outbreaks (‘ad hoc typing service’) for other healthcare facilities.
• The Reference Laboratory is now able to recognize 204 different PCR polymerase chain reaction (polymerase chain reaction) ribotypes.

Results of the sentinel surveillance (May 2014- May 2015)

• A mean incidence rate of 2.98 CDI per 10.000 patient-days was found through sentinel surveillance (varying between hospitals from 0.92 to 5.56 CDI per 10.000 patient-days), similar to last years.
• The disease severity was reported for 806 out of 931 patients included in the surveillance; 24% had severe CDI. The 30-day outcome was reported for 715 patients; 0.1% and 1.1% of the patients needed surgery or were admitted to the ICU intensive care unit (intensive care unit) due to CDI, respectively.
• 12.6% of the patients died within 30 days (n=90), of which 31 patients (4.3%) known to be contributable to CDI.
• No outbreaks were observed in the participating hospitals.
• The most frequent encountered PCR ribotypes included ribotype 014/020 (16.3%), the closely related ribotypes 078 and 126 (12.9%), and ribotype 002 (7.1%). The proportion of ribotype 001 decreased from 26.5 to 5.9% over a period of six years.
• Ribotype 027 was less abundant than in the last five years (0.7% compared to 2.3-4.2%).
  

Results of ad hoc typing (May 2014- May 2015)

• Eleven healthcare facilities/laboratories sent 133 strains to the Reference Laboratory for ad hoc typing because of outbreaks, severe CDI cases, or for other reasons.
• Ribotype 027 was the predominant ribotype, found in 14.3%, followed by ribotype 078/126 (13.3%).
• One 027 outbreak was observed in the North-Western part of the Netherlands, whereas five 027 outbreaks were reported in 2013-2014. Some 027 cases in surrounding nursing homes were detected as well. An outbreak management team was able to rapidly control the outbreak, and the local public health service was consulted to coordinate C. difficile-related measures in surrounding nursing homes.
  

Burden of CDI in the Netherlands

• Extrapolating the data of sentinel surveillance to all hospitals in the Netherlands (with a total of 9.400.000 patient-days per year1), it is estimated that approximately 2800 hospitalized patients will develop CDI, and 120 patients succumb contributable to CDI annually. In these estimations, the impact of CDI in other healthcare facilities than hospitals is not included.
• We observed a substantial decrease of the burden of ribotype 027 compared to the prior year.