Identificeren van micro-organismen bij aseptische handelingen

OBJECTIVE Determination of the relevance of identification of microorganisms found by microbiological Environmental Monitoring (isolates from EM) during aseptic handling. METHODS Identification of isolates from EM by microscopical examination, gram and spore staining and/or by MALDI-TOF. Isolates from EM in five hospital pharmacies were collected during one year and subdivided in 7 groups: Gram-positive and Gram-negative cocci. Gram-positive non-spore forming rods. Gram-positive spore forming rods. Gram-negative rods, fungi and yeast. RESULTS Gram-positive cocci were found in most cases (70-80 %). followed by Gram-positive rods (non-spore forming and spore forming; around 20%). Our results are comparable with the cleanroom microflora found in the pharmaceutical industry. The two cases described in this article, show that auditing gives more information about possible sources and causes of contamination than identification of micro-organisms. CONCLUSION The aim of identification is finding sources of contamination. resulting in corrective actions if EM results exceed the alert or action levels. We believe that the added value of identification, as a routine activity during aseptic handling is doubtful. However, knowing it is important to check if the cleanroom microflora is comparable to the expected microflora, we advise to do this once by using around 100 isolates from EM out of the LAF or biosafety cabinet and to repeat this every 3 years. Identification is also valuable while building activities are taking place in the neighborhood of the cleanroom. Deviations from the expected cleanroom microflora will be indicative for inadequate preventive measures against contamination resulting from the building activities.