A review on biocide reduced susceptibility due to plasmid-borne antiseptic-resistant genes-special notes on pharmaceutical environmental isolates.

Biocides (antiseptics and disinfectants) are widely used in hospitals and pharmaceutical industries for contamination control. The emergence of reduced susceptibility to biocides is the major concern and this is caused by various factors, among which plasmid-mediated resistance is common. Many publications describe the antibiotic resistance and mechanisms in a clinical setting. However, there are only limited studies available worldwide addressing the molecular mechanisms of biocide resistance in the pharmaceutical sector. In addition, there is a considerable lack of scientific reports regarding minimum inhibitory concentration (MIC) values of typical biocides against pharmaceutical cleanroom environmental isolates. This review analyses the plasmid-mediated resistance in typical pharmaceutical micro-organisms and prevalence of biocide-resistant genes among common clinical and pharmaceutical isolates. This review discusses the MIC values of biocides in pharmaceutical environmental isolates, indicating the importance of the correlation between the presence or absence of biocide-resistant genes and reduced susceptibility of MIC values. This review recommends that pharmaceutical organizations adopt policies and test methodologies to examine the MICs of common cleanroom biocides against the most common types of cleanroom environmental isolates.

A review of melanized (black) fungal contamination in pharmaceutical products--incidence, drug recall and control measures.

The aim of this study was to describe the incidence of contamination of pharmaceutical products by melanized fungi and to consider control measures in relation to bioburden and cleanrooms. This study reviews and analyses pharmaceutical product recalls and offers incidence rates of fungal detection from a typical cleanrooms. The recalls include some serious cases which resulted in the loss of life. Of different types of fungal contamination incidences some of the most damaging have been due to melanized fungi ('black mould'), such as Exserohilum rostratum. The focus of the article is with melanized fungi. The study concludes that, from the review of recent pharmaceutical product recalls, fungal contamination is either increasingly common within cleanroom environments or the accuracy of sampling and the level of reporting has risen. The prevalence of melanized fungi in pharmaceutical facilities rests on specific virulence factors particular to these types of fungi, which are outlined. The article identifies a gap in the way that such fungi are screened for using available cultural methods. The article provides some control strategies, including assessing the suitability of disinfectants and biocides, for reducing the risk of melanized fungal incidences within the pharmaceutical facility. Understanding the fungal risk to pharmaceutical products remains a poorly understood and often overlooked aspect of pharmaceutical microbiology. This article helps to identify this risk and offer some guidance to those involved with pharmaceutical products manufacture in relation to bio-contamination control strategies.

In vitro fungicidal activity of biocides against pharmaceutical environmental fungal isolates.

AIMS: To determine the minimum inhibitory concentrations (MIC) of a range of cleanroom fungi against three disinfectants common to the pharmaceutical and healthcare sectors: biguanide (chlorhexidine) and two quaternary ammonium compounds (benzalkonium chloride and cetrimide). METHODS AND RESULTS: The in vitro fungicidal activities of the three biocides were studied against 112 cleanroom fungal isolates using broth microdilution technique (CLSI M38-A2 standard). CONCLUSIONS: Minimum inhibitory concentration (MIC) for all three biocides against hyaline fungi showed results of not more than 16 µg ml(-1). Alternaria showed <32 µg ml(-1) and other dematiaceous fungi reported that 8-16 µg ml(-1) for biguanides and QACs. This study clearly demonstrates that the most frequently isolated micro-organisms from an environmental monitoring programme may be periodically subjected to broth microdilution testing with cleanroom disinfectant agents used in the disinfection programme confirm their sensitivity profile. SIGNIFICANCE AND IMPACT OF THE STUDY: No large collection of data exists on the activity of biocides on pharmaceutical cleanroom fungal isolates. This is the first study report with large collection of cleanroom fungal isolates tested against common biocides using the broth microdilution antifungal susceptibility testing to determine the MIC value. The data presented support a quality control procedure for cleanroom disinfection.

Application of rapid microbiological methods for the risk assessment of controlled biopharmaceutical environments.

AIMS: To assess the different operational states within a biopharmaceutical grade clean room, using a rapid microbiological method. The method was a novel system, based on spectrometry, designed for sampling, discriminating, and enumerating airborne particles. Central to the study was the aim to determine the microbiological levels as a clean room went from standard use through maintenance and shutdown, disinfection, and then back to standard use. The objective was to evaluate whether a rapid method could replace conventional environmental monitoring using growth-based media. METHODS AND RESULTS: The instrument evacuated was a BioVigilant IMD-A(®) System, which is a real-time and continuous monitoring technology based on optical spectroscopy that can differentiate between biological particles and inert ones (biological particles expressed as bio-counts based on the detection of microbial metabolites). The results indicated that certain activities lead to a high generation of biological particles and in showing an increase over the baseline, would be regarded as presenting a microbiological risk to the cleanroom. These activities include removing HEPA filter grilles, turning off an air handing unit, and tasks which requires an active personnel presence, such as cleaning and disinfection. CONCLUSIONS: The optical instrument can be used to process sufficient information, so that clean rooms can be returned to use following a period of unexpected downtime or following maintenance without the need to wait for the results from growth-based methods. As such, this type of rapid microbiological method is worth exploring further for clean room air monitoring. SIGNIFICANCE AND IMPACT OF THE STUDY: Few studies have been undertaken which examine air-monitoring devices that can both enumerate and discriminate particulates, in a volume of air as 'inert' or 'biological'. This study extends this limited field. Furthermore, the data collected in relation to cleanrooms is of interest in helping microbiologists understand that risks posed by different activities in relation to clean air-handling systems and personnel particle shedding.

Study of psychrophilic and psychrotolerant micro-organisms isolated in cold rooms used for pharmaceutical processing.

AIMS: To examine for psychrophilic or psychrotolerant micro-organisms in pharmaceutical cold rooms (in relation to numbers, incidents and species) and to determine, where such micro-organisms are present, whether standard microbiological environmental monitoring regimes require modification. This is presented as a case study. METHODS AND RESULTS: Comparative environmental monitoring within different pharmaceutical facility cold rooms (using standard mesophilic and low temperature incubation). Data were collected over two periods, 5 years apart. The results indicated that psychrophilic micro-organisms were not present and that those micro-organisms deemed psychrotolerant, primarily pseudomonads, could be grown on standard media under mesophilic conditions. CONCLUSIONS: Psychrophilic micro-organisms were not detected and those considered to be psychrotolerant were only found in low numbers. Pyschrotolerant organisms were recovered under both low temperature incubation conditions and under standard conditions (between 20 and 35°C). Further evaluation may be required, using alternative agar, and microbiologists should regularly review the species recovered to note differences between different environments. SIGNIFICANCE AND IMPACT OF THE STUDY: The study came about from requests made by US and UK regulators concerning the risk of any extremophiles present in pharmaceutical manufacturing facilities upon product safety. Regulators expressed concerns about whether standard, and accepted, environmental monitoring regimes were capable of detecting such micro-organisms. The data provide a benchmark to support pharmaceutical manufacturers in relation to their existing monitoring programmes or as a case study with which to undertake a similar study.