Skin cleaning before catheterization

There are microbial risks associated with catheterisation and there has been a long running debate as to whether simple skin cleaning or the use of an antimicrobial is the most effective method. The concern is with reducing the risk of CAUTIs (catheter urinary tract infections). One risk is that bacteria can colonise a catheter and form biofilms, which involve clusters of cells covered in a protective matrix of polysaccharide polymers.

The purpose of urinary catheterisation is to drain urine from the bladder into a collection device, such as a catheter bag. The catheter itself comprises a flexible tube, usually manufactured from silicone, which is inserted through the urethra or sometimes via an abdominal incision (suprapubic catheterisation).

In an article for Inside Hospitals, Dr. Tim Sandle has presented a study looking at the efficacy of an antimicrobial cleaning solution prepared from octendine dihydrochloride. The study looked at the ability of the solution to reduce levels of bacteria on human skin.

The reference is:

Sandle, T. (2013). Skin cleaning before cathererisation, Inside Hospitals, October 2013, pp40-41

Copies can be requested from Tim Sandle

Posted by Tim Sandle

Birds carry resistant bacteria

Researchers from Tufts University in Massachusetts, Binghamton University in New York, the University of California, Davis, and the University of Veterinary and Pharmaceutical Sciences Brno in the Czech Republic have found vancomycin-resistant Enterococci (VRE) in fecal samples from American crows (Corvus brachyrhynchos), which live in close proximity to humans in urban areas.

The research team collected 590 samples crow feces from four different locations in the United States—in California, Kansas, New York, and Massachusetts. They found that Enterococci in 2.5 percent of the samples carried vanA, one of nine vancomycin-resistance genes. In addition to being resistant to vancomycin, bacterial strains that the research team isolated were also resistant to other antibiotics, including erythromycin, ampicillin, and ciprofloxacin.

The findings have been published online in Environmental Microbiology.
Posted by Tim Sandle

Use of nanotechnology to fight fungal infections

Researchers have converted recycled plastic bottles into non-toxic and biocompatible materials designed to specifically target and attack fungal infections.

With this breakthrough, a research team used nanotechnology and converted common plastic materials like polyethylene terephthalate (PET), which is the plastic used to make drinks bottles.

The newly formed anti-fungal agents self-assemble through a hydrogen-bonding process, sticking to each other like molecular Velcro in a polymer-like fashion to form nanofibers. Infection Control notes that this novel nanofiber carries a positive charge and can selectively target and attach to only the negatively-charged fungal membranes based on electrostatic interaction. The new compound then breaks through and destroys the fungal cell membrane walls, preventing the fungus from developing resistance.

The in vivo antifungal activity of the nanofibers was evaluated in a mouse model using a contact lens-associated yeast infection, according to Controlled Environments.

The reason behind the new nano tech is because traditional anti-fungal therapeutics need to get inside the cell to attack the infection but have trouble targeting and penetrating the fungi membrane wall. This process is complex and not always successful.

The research was conducted by IBM and the Institute of Bioengineering and Nanotechnology. The findings have been reported in the journal Nature Communications. The article is titled “Supramolecular high-aspect ratio assemblies with strong antifungal activity”.

Posted by Tim Sandle

A new standard for bioburden testing

The USP has proposed a new standard for bioburden testing (USP chapter 1115). The main basis of the chapter is setting out a risk based approach to monitor and control a manufacturing facility for the processing of non-sterile products.

To examine the implications of the proposed chapter, and in a review of bioburden issues in general, Tim Sandle has written an article for the GMP Review.

The reference is:

Sandle, T. (2013). A new standard for bioburden testing: USP chapter in development, GMP Review, 12 (3): 10-12

For further details, please contact Tim Sandle

Posted by Tim Sandle

Are Cleanrooms Clean?

In the current edition of the Gold Sheet, Bowman Cox addresses some of the findings raised at the recent PDA Microbiology conference (October 2013, Bethesda MD, USA).

The review centers on presentations made around the subject of the Human Microbiome project and the implications that this raises for cleanroom microbiology. The presentations reviewed are by Tim Sandle and Karen Nelson.

Nelson’s presentation presented an overview of the human microbiome findings, whereas Sandle’s presentation addressed the microbial ecology of human skin and some of the issues that this raises for cleanroom contamination control. Sandle’s focus was upon the role of skin shedding, the limitations of microbiological culture media, the viable-but-non-culturable issue, the need to expand media and disinfectant panels with environmental isolates, and the anaerobic microorganism issue. Dr. Sandle also raised considerations for the investigation of microbial data deviations.

The reference for this informative overview is:

Cox, B. (2013). Are Cleanrooms Clean? Human Microbiome Project Raises Some Questions, The Gold Sheet, 47 (11): 16-18

Posted by Tim Sandle

Microorganism fact sheets

Microbial Examination of Non-Sterile Products

To help as a training aid and to remind laboratory staff about the different types of microorganisms associated with the microbial examination of non-sterile products (as described in USP 62 and Ph Eur 2.6.13), Pharmig have produced eight fact sheets. The sheets were written and prepared by Tim Sandle

Seven of the fact sheets profile each one of the key microorganisms (or microbial groups), using color photographs illustrating growth on agar and by Gram-stain.

The microbial enumeration test and test for specified microorganisms can represent a challenging area for pharmaceutical microbiology (these are the tests for the ‘Microbiological Examination of Nonsterile Products’ as described in USP and Ph. Eur. 2.6.12. One of the main challenges with the test relates to identifying and characterising the specific microorganisms required by the test. To act as a training aid for new staff, and an aide memoire for more experienced staff, Pharmig have produced eight fact sheets. Seven of the fact sheets profile each one of the key microorganisms (or microbial groups), using color photographs illustrating growth on agar and by Gram-stain. These are supported by facts relating to the organism’s profile and methods for identification. The eighth sheet offers some useful guidance about the interpretation of the test. The sheets are presented in a pack and together provide a unique, informative and colorful guide to an important area of quality control microbiology.

For further details, see Pharmig.

Posted by Tim Sandle

New anti-fungal treatment

An anti-fungal composition with pharmacological applications in agriculture and food industry, has been developed.

The composition, developed and patented by the UA Research Group in Plant Pathology, is based on the combined use of chitosan, or chitosan oligosaccharides (COS), antifungal agents and additives that synergistically affect the growth of a variety of pathogenic fungi.

The various experiments carried out by the research group are proof of the significant synergistic effect of the combination of chitosan (or COS) and other antifungals and ARL1 gene inhibitor, in inhibiting the growth of mould and yeast.

The compound has been developed by researchers based at the University of Alicante. For further details see UA Research.

Posted by Tim Sandle

South Africa joins the European Pharmacopoeia

The 37 signatory states of the European Pharmacopoeia Commission and the Commission of the European Union have unanimously decided to grant The Medicines Control Council of South Africa Observer Status to the European Pharmacopoeia. This brings the number of observers to twenty-five, including the World Health Organization (WHO).

South Africa’s application and acceptance as an Observer by EDQM for the European Pharmacopoeia is recognition of the large strides South Africa has made in the past decade and will allow the regulator and ultimately the local pharmaceutical industry to gain more expertise in the specialised field of plasma fractionation through the Ph.Eur. structures. It comes soon after the South African Medicine Control Council’s acceptance into PIC/S, once again, highlighting significant development taking place within the regulatory framework to the benefit of the patients of South Africa receiving PDMP.
For details, see SA EP

Posted by Tim Sandle

Rapid diagnosis of typhoid from blood cultures

Typhoid fever is a life-threatening illness caused by the Gram-negative bacterium, Salmonella enterica subsp. enterica serovar Typhi. This foodborne pathogen is commonly contracted though the consumption of food or water that has been handled by a person shedding S. Typhi, or through the contamination of these products with sewage. Once ingested, the bacteria will inhabit the intestinal tract and bloodstream, resulting in a variety of complications including high fever, stomach pains, septicemia, and death.

Typhoid fever is common throughout most of the developing world, particularly in parts of Asia, Africa, and Latin America. Unfortunately, a number of people within these countries do not have access to a reliable laboratory diagnosis as the appropriate clinical facilities and techniques are not available. Thus, there is an urgent need for an inexpensive, easy-to-use, portable technique that can rapidly and safely diagnose typhoid fever independent of a hospital setting.

In a recent study, Castonguay-Vanier et al. investigated the accuracy and efficacy of a technique combining blood culture amplification of S. Typhi with a S. Typhi antigen rapid diagnostic test (RDT) developed by Standard Diagnostics (Cat. No. 15FK12). When tested against 23 Gram-negative reference pathogens, this assay was able to detect S. Typhi, as well as Salmonella enterica serovar Enteritidis and Salmonella enterica serovar Ndolo. The precision of this assay was further analyzed through the examination of 6,456 blood cultures from 3,028 patients. From this prospective study, the group found that the sensitivity, negative predictive value, specificity, and positive predictive value were 96.7%, 99.5%, 97.9%, and 87.9%, respectively, for patients with proven S. Typhi bacteremia. Overall, these results suggest that the combination of blood culture amplification of S. Typhi with an S. Typhi RDT is promising as an effective, sensitive, and inexpensive tool for the rapid diagnosis of typhoid fever.

This news was via ATCC. To access the research study, click here.

Posted by Tim Sandle

Water Quality Concerns

Hospital water systems are of importance for a number of applications, including supplying equipment, irrigation, washing patients, and for staff hand washing. It follows that managing a hospital water system plays a key part in contamination control. The risks are foremost to the patient, with a secondary risk to the healthcare worker. Contamination also presents an economic burden to the hospital, especially the cost of rectifying the contamination within the water system.

 Water presents a ‘dual problem’ because it not only provides a medium for microorganisms to grow, it is also easily spread and contamination can pass over large areas through the spread of water droplets and via aerosols. To explore the issues of good water system management, Tim Sandle has written an article for the magazine European Medical Hygiene.

 In the article, Dr. Sandle addresses the types of microorganisms found in water systems; the types of organisms that might be considered as ‘objectionable’; good control practices for water systems; biofilm risks; and good design principles.

The reference is:

Sandle, T. (2013). Water Quality Concerns: Contamination control of hospital water systems, European Medical Hygiene, pp14-19

Copies of the article were distributed at Medica in November 2013. If you would like to obtain a copy, please contact Tim Sandle

Pharmig News #53

A new edition of Pharmig News has been issued (number 53). The highlights in the new issue are: 

• An article on cleanroom gloves and the required criteria, by Derek Watts
• An article about genotypic microbial identification, by Vikki Mitchell
• A book review of ‘Cleanroom Management in Pharmaceuticals and Healthcare’
• A regulatory roundup by Tim Sandle
• And more…

Copies will have been sent to Pharmig members. If you would like a copy, please contact Maxine Moorey at Pharmig.

Posted by Tim Sandle

Bacterial Endotoxins Test

The FDA has published Q4B Evaluation and Recommendation of Pharmacopoeial Texts for Use in the ICH Regions Annex 14 Bacterial Endotoxins Test General Chapter This annex is one in a series of guidance documents that describe the evaluations and recommendations by the Q4B Expert Working Group (EWG) of selected pharmacopoeial texts to facilitate their recognition by regulatory authorities for use as interchangeable in the ICH regions. Implementation of the Q4B annexes is intended to avoid redundant testing by industry.

The analytical procedures described in the official pharmacopoeial texts, European Pharmacopoeia (Ph. Eur.): 2.6.14. Bacterial Endotoxins, Japanese Pharmacopoeia (JP): 4.01 Bacterial Endotoxins Test, and United States Pharmacopeia (USP) General Chapter <85> Bacterial Endotoxins Test, can be used as interchangeable in the ICH regions subject to the following conditions:

Any of the three techniques can be used for the test. In the event of doubt or dispute, the gel-clot limit test should be used to make the final decision on compliance for the product being tested.

The USP, JP, and Ph. Eur. reference standards are considered interchangeable because they have been suitably calibrated against the WHO (World Health Organization) International Standard for Endotoxin.

In the section Photometric quantitative techniques, Preparatory testing, Test for interfering factors, the user should perform the test on solutions A, B, C, and D on at least two replicates using the optimal conditions as recommended by the lysate manufacturer.

For further details, see BET.

Posted by Tim Sandle

Comparison of Different Fungal Agars

A new paper of interest has been published: ‘Comparison of Different Fungal Agar for the Environmental Monitoring of Pharmaceutical-Grade Cleanrooms’. The paper has been written by Barbara Gebala and Tim Sandle.

The abstract for the paper reads:

“In relation to a growth in reported incidents of fungal contamination of pharmaceutical products, there has been a developing interest by U.S. and U.K. regulators concerning the risk of fungi. This paper describes a study undertaken to examine the suitability of different commercially available mycological agars for the environmental monitoring of pharmaceutical-grade cleanrooms. Five agars were evaluated in relation to the detection of both numbers and different species of fungi (yeasts and moulds). The objective was to determine if one mycological medium is more suitable than another. Data was collected using different sampling techniques (settle plates, active air samples, and contact plates) from different locations within representative cleanrooms. Samples were taken over a 3 month time period. The study results indicated that fungi are not distributed evenly across cleanrooms and that that the prevalence of fungi partly relates to the room design and operation. In relation to the different agar types, the study indicated that Sabouraud dextrose agar was the most effective at detecting the widest number of different types of isolates, and that Sabouraud dextrose agar and malt extract agar were the most efficient in terms of the numbers of recovered isolates. Other media, notably potato dextrose agar, was relatively less effective.”

The reference is:

Comparison of Different Fungal Agar for the Environmental Monitoring of Pharmaceutical-Grade Cleanrooms
Barbara Gebala and Tim Sandle
PDA J. Pharm. Sci. Technol. 2013; 67:621-633

Posted by Tim Sandle

Dimorph and Filamentous Fungi

The primary risk to the immunocompromised patient arises from nosocomial infections (or hospital acquired infections). A risk to patients additionally can arise from administered medicines. Until the late 1990s the primary risk was generally regarded as arising from bacteria. However, since 2001 the second most common recall for pharmaceutical medicines has been due to fungal contamination. Moulds are ubiquitous in nature and, therefore they pose a risk to pharmaceutical manufacturing operations. Aspergillus spp., Penicillium spp., Trychophyton spp., and other filamentous fungi have, in some cases, caused significant microbial contamination issues in production environments and manufactured products.

With this important subject, Tim Sandle has written a freely accessible chapter for the book ‘Bacterial and Mycotic Infections in Immunocompromised Hosts: Clinical and Microbiological Aspects’ (edited by Maria Teresa Mascellino), which presents an introduction to this topic of fungal infections of the immunocompromised person. The book is published by OMICS Group eBooks.

"This chapter examines the risks to immunocompromised patients from fungal infections. In doing so the chapter identifies and describes the most common types of infections. The chapter additionally discusses some of the steps taken for the microbiological isolation and assessment of the clinically significant microorganisms and provides an introduction to some of the treatment steps."

The chapter can be viewed on-line here, or as a downloadable pdf document here.

Posted by Tim Sandle

The multiple roles of antibiotics and antibiotic resistance in nature

Fiona Walsh, Agroscope Changins Wädenswil, Wädenswil, Switzerland, has written an interesting overview of antibiotics and antibiotic resistance for Frontiers Microbiology.

There have been many calls for more information about the natural resistome and these have also highlighted the importance of understanding the environmental resistome in the preservation of antibiotics for the treatment of infections. However, to date there have been few studies which have investigated the roles of antibiotics and resistances outside of the clinical environment. This lack of data also highlights the difficulties faced by microbiologists in designing these experiments to produce meaningful data. Antibiotics and antibiotic resistance have most commonly been viewed in the context of human use and effects. However, both have co-existed in nature for millennia. Recently the roles of antibiotics and antibiotic resistance genes have started to be discussed in terms of functions other than bacterial inhibition and protection. This special topic has focused on both the traditional role of antibiotics as warfare mechanisms and their alternative roles and uses within nature.

The research topic starts with an introduction into antimicrobial resistance in medicine, its linkage to the global environmental microbiota and the many different roles of antibiotics and antibiotic resistance in nature, providing the background to the topic (Cantas et al., 2013). The following chapter discusses the idea that the understanding of antibiotic resistance implies expanding our knowledge on multi-level population biology of bacteria (Baquero et al., 2013). This brings with it inherent problems of designing experimental procedures and standards that can be used in many different microbiomes from human to soil and is discussed further by Walsh (Walsh, 2013). A number of models are proposed to study and understand the biological impact of selection and diversification of antibiotic resistance mechanisms, in particular using the β-lactamases as models (Galán et al., 2013; Patel and Bonomo, 2013; Popowska and Krawczyk-Balska, 2013). The β-lactamases constitute the most widespread mechanism of resistance, at least among pathogenic bacteria, with more than 1000 enzymes identified in the literature. We present some examples of the alternative functions for the multi-drug resistance mechanisms of efflux, that range from bacterial interactions with plant or animal hosts, to the detoxification of metabolic intermediates or the maintenance of cellular homeostasis and also the potential role of extracellular DNA in antibiotic resistance and virulence (Alvarez-Ortega et al., 2013). Bacterial responses to antibiotics may be concentration dependent and so we discuss the different types of interactions mediated by antibiotics and non-antibiotic metabolites as a function of their concentrations and speculate on how these may amplify the overall antibiotic resistance/tolerance and the spread of antibiotic resistance determinants in a context of poly-microbial community (Bernier and Surette, 2013; Lewenza, 2013; Sengupta et al., 2013). The use of antibiotics may also be regarded as pollution. Thus, the widespread use and abuse of antibiotic therapy has evolutionary and ecological consequences, some of which are only just beginning to be examined (Gillings, 2013).

These papers thoroughly review the many different aspects of antibiotic resistance and the roles of antibiotics in nature and link these to the emerging antibiotic resistances of particular importance to the treatment of infectious diseases.

References

Alvarez-Ortega, C., Olivares, J., and Martínez, J. L. (2013). RND multidrug efflux pumps: what are they good for. Front. Microbiol. 4:7. doi: 10.3389/fmicb.2013.00007

Pubmed Abstract | Pubmed Full Text | CrossRef Full Text

Baquero, F., Tedim, A. P., and Coque, T. M. (2013). Antibiotic resistance shaping multi-level population biology of bacteria. Front. Microbiol. 4:15. doi: 10.3389/fmicb.2013.00015

Pubmed Abstract | Pubmed Full Text | CrossRef Full Text

Bernier, S. P., and Surette, M. G. (2013). Concentration-dependent activity of antibiotics in natural environments. Front. Microbiol. 4:20. doi: 10.3389/fmicb.2013.00020

Pubmed Abstract | Pubmed Full Text | CrossRef Full Text

Cantas, L., Shah, S. Q. A., Cavaco, L. M., Manaia, C. M., Walsh, F., Popowska, M., et al. (2013). A brief multi-disciplinary review on antimicrobial resistance in medicine and its linkage to the global environmental microbiota. Front. Microbiol. 4:96. doi: 10.3389/fmicb.2013.00096

Pubmed Abstract | Pubmed Full Text | CrossRef Full Text

Galán, J. C., González-Candelas, F., Rolain, J. M., and Cantón, R. (2013). Antibiotics as selectors and accelerators of diversity in the mechanisms of resistance: from the resistome to genetic plasticity in the β-lactamases world. Front. Microbiol. 4:9. doi: 10.3389/fmicb.2013.00009

Pubmed Abstract | Pubmed Full Text | CrossRef Full Text

Gillings, M. R. (2013). Evolutionary consequences of antibiotic use for the resistome, mobilome and microbial pangenome. Front. Microbiol. 4:4. doi: 10.3389/fmicb.2013.00004

Pubmed Abstract | Pubmed Full Text | CrossRef Full Text

Lewenza, S. (2013). Extracellular DNA-induced antimicrobial peptide resistance mechanisms in Pseudomonas aeruginosa. Front. Microbiol. 4:21. doi: 10.3389/fmicb.2013.00021

Pubmed Abstract | Pubmed Full Text | CrossRef Full Text

Patel, G., and Bonomo, R. A. (2013). “Stormy waters ahead”: global emergence of carbapenemases. Front. Microbiol. 4:48. doi: 10.3389/fmicb.2013.00048

Pubmed Abstract | Pubmed Full Text | CrossRef Full Text

Popowska, M., and Krawczyk-Balska, A. (2013). Broad-host-range IncP-1 plasmids and their resistance potential. Front. Microbiol. 4:44. doi: 10.3389/fmicb.2013.00044

Pubmed Abstract | Pubmed Full Text | CrossRef Full Text

Sengupta, S., Chattopadhyay, M. K., and Grossart, H. P. (2013). The multifaceted roles of antibiotics and antibiotic resistance in nature. Front. Microbiol. 4:47. doi: 10.3389/fmicb.2013.00047

Pubmed Abstract | Pubmed Full Text | CrossRef Full Text

Walsh, F. (2013). Investigating antibiotic resistance in non-clinical environments. Front. Microbiol. 4:19. doi: 10.3389/fmicb.2013.00019

 
Posted by Tim Sandle