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Anaerobic Bacteriology
	What is your opinion on the use of a broth medium (such as thioglycollate) to replace "regular" anaerobic culture on selected sterile body fluids, such as pleural, synovial, CSF? If this seems to be an acceptable practice, should we be holding the broth for 3 days or 5? Also, what about sterile fluids that are more likely to exhibit growth, such as abdominal? (answered 06/01/2007)
	HOW LONG SHOULD ANAEROBIC SPECIMENS BE EXPOSED TO ROOM AIR WHILE SUB CULTURING OR EXAMINING PLATES? (answered 05/29/2007)
	Does a specimen for c.diff need to be warm? (answered 02/26/2007)
	What QC organisms are routinely being used for anaerobe susceptiblity testing? It's unclear for microbroth dilution which are to be used. CLSI suggest a B. fragilis group.... one or more....? Can I use B. thetaiotamicron and E. lentum? Or do I need to additionally test B. fragilis? How many organisms and which ones? (answered 02/14/2007)
	Is it necessary to use prereduced anaerobic media? (answered 02/14/2007)
	I want to know F. nucleatum is a pure anaerobe or facultative anaerobes can we grow in anaerobic conditiion? (answered 02/08/2007)
	We have recently isolated branching gram postive rods in mixed cultures from genital and bronchial washing sources. They are small white colonies, catalase negative. They do not ID on the API Coryne system or our ANI cards. We believe they are probably Actinomyces or Bifidobacteria. They were the predominant organisms. Are they significant? Can Actinomyces species be normal flora in repsiratory and/or genital specimens? Is there any way to get the organisms into either of these categories without ID's on kit systems? Is it ever ok to report possible Actino sp without having something definitive to put it there? How far do you go when it isn't a single organism, and you question the significance? (answered 01/26/2007)
	Is it necessary to sub a turbid chopped meat broth if the anaerobic plates are growing, and the isolates match the gram stain? Aren't chopped meat broths intended to be only a back up in case anaerobiosis was not acheived? And, who answers these questions? (answered 01/09/2007)
	Can the abscence of stool fecal leukocytes/lactoferrin be used as a screening tool to determine if C.diff toxin testing should be performed? ie -if fecal leuk negative then no C.diff toxin assay done. (answered 09/12/2006)
	Dear Ask it Experts: According to M11-A6 document, the interpretive categories and correlative MIC‘s for amoxicillin/clavulanic acid to anaerobic bacteria are: susceptible ≤ 4/2, Intermediate 8/4 and Resistant ≥ 16/8. Is it correct to assume that the given values in the document can be extrapolated for amoxicillin ? (susceptible ≤ 4, Intermediate 8 and Resistant ≥ 16) I am almost sure that this is not possible but I need the advice from one expert. Thank you (answered 08/21/2006)
	We want the selective growth of facultative anaerobes to find the efeect of chicken microbes on degradation of some plant compounds. Can we use metronidazole to inhibit the growth of obligate anaerobes and for selective growth of facultative anaerobes and what will be concentration of metronidazole? (answered 08/09/2006)
	Can C. difficile grow on nutrient agar (assuming incubation under anaerobic conditions at 35 C)? (answered 07/18/2006)
	I WANT TO KNOW SPECIFIC CULTURE MEDIA FOR SEPERATING FACULTATIVE AND OBLIGATE ANAEROBES (answered 07/03/2006)
	Is a hard formed stool an acceptable specimen for C.diff toxin testing by EIA. (answered 05/20/2006)
	In the opinion of your experts, does a first time positive C. difficile test result qualify as a critical result, and thus be phoned to the physician? (answered 05/20/2006)
	Our Infection Control RN is asking us to type the Clostridium difficile strain that is causing increasing concern due to its virulence and resistance to standard recommended treatment. Is there currently a test available to do this? (answered 05/19/2006)
	At what point should we "gross out" and anaerobic culture. We get two different situations, which I believe are caused by poor specimen collection. In the first we get multiple aerobic isolates that can be considered skin flora and contaminants. I believe this precludes any workup on either culture, since the specimen is suspect and the aerobes generally are facultative and overgrow the anaerobic plates. The second is we get multiple (3 or more) possible anaerobes. Does this indicate a "Gross out"? Is there a number of isolate types at which a decision to not proceed can be made? We do try to correlate with the gram stain, but are hoping for further guidance. Thank You. (answered 05/11/2006)
	Dear Ask it Our Infectious disease specialist has read several articles published recently about a strain of C. difficile, NAP1/027, that is a hyper-producer of toxin, which has resulted in treatment problems. She would like to have a couple of problem patients tested but I am unable to find anyone who not only performs the test for this strain or knows anyone who tests for the strain. I would appreciate if you could tell me where the test to identify this particular strain is available. Thanks Ed (answered 05/02/2006)
	What is acceptable practice in preliminary reporting of anareobic cultures? Should the prelim. report go out as "no anaerobic growth after 48 hours" or "possible anareobes isolated- work up to follow."? We have a tech who send out a prelim "Anaerobic culture in progress" and I find that gives the clinician no information as to where the culture stands. (answered 02/28/2006)
	According to the M11A5 document, from CLSI, wo found that the breakpoints for anaerobic bacteria are as follows: Metronidazole: 8 ug/ml Clindamycin: 2 ug/ml Tetracycline: 4 ug/ml Amoxicillin: 4 ug/ml Azithromycin: 4 ug/ml In the new M11A6 document are any changes? We also want to know if there are reports about susceptibilities breakpoints for anaerobic bacteria to Ciprofloxacin. (answered 02/14/2006)
	We are considering changing the routine incubation period for anaerobic cultures from 48 hr to 5 days as recommended in the current edition of the ASM Manual of Clinical Microbiology. I have several questions regarding efficiency of workflow. 1) Should the aerobic plates be discarded after their routine 48 hr incubation period or kept until the anaerobic culture is complete? 2) Should the anaerobic plates be reincubated after an initial 48 hr read or would it be better to set up two sets of anaerobic plates, one to be read at 48 hr and the other to be incubated undisturbed for 5 days before examining the plates? 3) Is there a recommended approach for comparing the growth between the 48 hr and 5 day anaerobic plates without repeating previously worked up organisms that were done from the 48 hr plates? I would appreciate any suggestions that would prevent unnecessary workups and provide ease of workflow. Thank you. (answered 02/08/2006)
	Our aerobic laboratory recently deleted thioglycollate broth from routine set up of all wound cultures and critical specimens. Our anaerobe lab is still setting up thioglycollates on all culture requests. We gram stain all positive thios, regardless of growth on the original plates or presence of aerobes. It has been my experience (working in the anaerobe lab for the last five years) that if aerobes are present, they quickly take over the thio. I have not found any significant anaerobes in these thios that were not already growing on the original cultures, with one possible exception. My question is this: Is it necessary to stain positive thioglycollates when the culture has aerobes growing, or when the culture is already growing several possible anaerobes? (answered 02/01/2006)
	isolation of anaerobic bifidobacterium-simple techniques (answered 01/13/2006)
	I will be resuming work shortly on identifying anaerobic bacteria in a particular effluent. The laboratory here is as yet rudimentary, in terms of availability of media and instruments. I learnt that to handle anaerobes, one requires gas-pak or anaerobic chambers. Is there a way to make do without those? :G.Jagannathan,India. (answered 01/05/2006)
	beta-lactamase anaerobes- should a beta-lactamase test be performed on anaerobic gram positive rods or anaerobic gram positive cocci? (answered 12/20/2005)
	CAP Survey D-B 2005 specimen D-11 states that "as a minimum, a beta-lactamase test should be performed and reported on Bacteroides fragilis". I thought that all B. frag should be considered beta-lactamse positive and resistant to penicillin. If a beta-lactamase test was performed on a B. frag/B. frag group and reported as negative, wouldn't this be misleading for treatment purposes? Why continue to perform beta-lactamase if all should be reported resistant to penicillin? (answered 12/12/2005)
	TIME FRAME FOR LABILITY OF TOXIN A AND TOXIN B AT ROOM TEMPERATURE?? (answered 10/31/2005)
	I'm searching for a new methodology for anaerobes in our lab. because the current system that we're using is not very accurate and good only for bacteroides other anaerobes are being missed. Please help me thanks. (answered 10/26/2005)
	What conditions must be present for botulism to set up in leftover baked potatoes (answered 10/21/2005)
	Fusobacterium nucleatum is described as vanco R, usually breadcrumb colonial morphology and fusiforme appearance on gram stain. Occasionally, we do a commercial biochemical ID panel on an anaerobic non-fusiforme, non-breadcrumb, vanco R anaerobic gnb and we get a 50/50 choice of F. nucleatum and F. necrophorum with lipase as the differentiating test. The lipase is always negative at 7 days which would indicate F. nucleatum. However lacking the other characteristics, we doubt that ID. So my question is - if the anaerobic gnb does NOT have fusiforme morphology on gram stain and does NOT have bread crumb colonial morphology can we say that it is NOT F. nucleatum? Does F. nucleatum ever not appear fusiforme? (answered 08/15/2005)
	we have a mixed culture of klebsiella and ?clostridium but we do not have any anaerobic testing methods except for Robertson cooked meat(rcm). Any Suggestions? (answered 07/05/2005)
	Is there a new drug for C diff called something like Floristar?(not sure if spelling) (answered 06/21/2005)
	What is the clinical significance of a positive CDiff toxin on a formed stool specimen. (answered 06/10/2005)
	Is it acceptable to use only solid media for anaerobic cultures? Is liquid media necessary for any anaerobic cultures? (answered 05/03/2005)
	We are a small hospital that is just now starting a micro department, in which we plan on doing "routine" micro in-house and continuing to send out "non-routines" to a reference lab. We plan to work up all aerobes isolated, but in the case of anaerobes, it will not be profitable for us to keep the necessary items to work up any anaerobes isolated. Therefore, we are planning on setting up anaerobic culture plates on appropriate specimens, but if we grow anaerobes, we plan to send the plates to our reference lab for work up. Is it acceptable to set up a regular BAP and CHOC plate for anaerobes, since it is not financially feasible for us to keep anaerobic media on-hand? Thank you. (answered 04/12/2005)
	When there is a request for an aerobic and an anaerobic culture to be set up should the specimen(ex.aspirate or tissue)be submitted in both an anaerobic transport medium(vial or swab) and an additional aerobic container(vial or swab)? (answered 04/05/2005)
	how much work do you do on mixed anaerobic cultures? (answered 04/05/2005)
	THE CAP 2004 CHECK LIST MIC.22700 BRINGS UP STATES USUAL MEDIA FOR ANAEROBES INCLUDE AN ANAEROBIC BLOOD AGAR PLATE, A MEDIUM THAT INHIBITS GRAM POSITIVE AND FACULTATIVE GRAM NEGATIVE BACILLI SUCH AS KV BLOOD PLATE, A DIFFERENTIAL OR SELECTIVE MEDIUM SUCH AS BBE, AND A GRAM POSITIVE SELECTIVE MEDIUM SUCH AS PEA. WE CURRENTLY ONLY SET UP A KV AND A ANABAP. I THOUGHT WE COULD RECOVER ANY ANEROBES. IS IT REALLY NECESSARY FOR US TO ADD THE BBE AND THE PEA TO ALL OUR ANAEROBIC CULTURES? SOUNDS EXPENSIVE. (answered 03/03/2005)
	What are the acceptable methods of reducing purchased anaerobic culture media (such as CDC anaerobic blood agar, PEA and KVLB agar) prior to use? (answered 03/03/2005)
	We are using the Triage C.Diff panel for testing for C.Diff antigen and toxin A.Our protocol is to run the test,if the antigen and toxin are negative the test is resulted as so,if the antigen and toxin is positive it is also resulted.If the antigen is positive but the toxin negative,then the specimen is sent to a ref lab for testing for toxin A by EIA and toxin B by cell culture.Is this a good protocol to cover the lower sensitvity of the test for detecting toxin A and also to cover for toxin A negative,toxin B positive C.Diff.Is the antigen detection part of the kit sensitive enough to be able to reassure the clinicains that we are not missing many positives by using this protocol.Or is there a better way,we don't test sufficient numbers to be able to batch. Many thanks,Keith. (answered 02/20/2005)
	I want to know what exactly is a Actinomyces bacteria and how do you get infected if you have that bacteria in the vagina. Is it a sexualy transmited infection? If so, does my parter have to be treated too? (answered 02/11/2005)
	Bifidobacterium Longum is a gram positive organism that is anaerobic. Is is a strict anaerobe or can it grow in the presents of oxygen? If it can grow in the presents of oxygen, what should the temperature be? (answered 12/16/2004)
	Where can I find information about the anaerobic sheep blood agar? How to use it? What organisms are isolated? Is there any quality control? (answered 10/28/2004)
	Is there any value in setting up aspirate specimens (i.e. pus, fluids) for anaerobic culture if they are not transported to the lab in an anaerobic transport container and the sample is >2 hr old? (answered 10/12/2004)
	I am trying to determine a cost effective method for the transport of tissues for anaerobic/aerobic culture. I read that Cary Blair is a possibility. Is this correct? What are your suggestions. We do not do much in the way of out-patient cultures. (answered 10/12/2004)
	What is the recommendation for testing for c. diff? Should a combination of toxin and common antigen testing be performed? (answered 10/02/2004)
	is clostridium botulinum a lactose fermenting bacteria (answered 10/01/2004)
	Textbooks usually recommend an incubation period of 5 - 7 days for the detection of anaerobes. Our experience has been that anaerobes are usually detected in culture after 48 - 72 hr of incubation. Would 72 hr be an appropriate incubation period for the detection of anaerobes unless otherwise indicated in the direct gram smear? (answered 09/28/2004)
	I want to isolate Treponema dentocola from oral samples. Is there a selective agar plate to isolate them? (answered 07/12/2004)
	What is the percentage of resistance of Peptostreptococcus to metronidazole? (answered 05/13/2004)
	As a cost-containment measure, it occurred to me that perhaps anaerobes could be initially cultured in a broth media only (such as chopped meat agar). Then, if there is growth, subbed to LKV and KV. There does not seem to be any information supporting this. It would cut down tremendously on wasted LKV and KV plates. It it acceptable protocol? (answered 05/11/2004)
	What is the procedure for the isolation of Actinomyces from IUD specimens? The Manual of Clinical Micro implies using two sets of cultures and is not explicit on whether the IUD should be cut into smaller portions and placed in broth and vortexed. Can you also include a source (The CMPH did not have an explicit procedure also). (answered 05/06/2004)
	What is the procedure for the isolation of Actinomyces from IUD specimens? The Manual of Clinical Micro implies using two sets of cultures and is not explicit on whether the IUD should be cut into smaller portions and placed in broth and vortexed. Can you also include a source (The CMPH did not have an explicit procedure also). (answered 05/06/2004)
	We don't do sensitivities on anaerobes. Is it useful to perform a beta lactamase test? (answered 12/01/2003)
	How do I refresh palladium catalyst (answered 10/31/2003)
	I have a question about the safety of anerobic gas (10% hydogen, 10% CO2 in Nitrogen). We want to place the cylinders out of the lab about 5 meters from an air-conditioning inlet. The engineering department at hospital are concerned that a leak will place hydrohen into the airconditioning system and the pipes back to the lab may one day be damaged and also release hydrogen into unwanted places. Should we be concerned with this concentration of hydrogen in these conditions? (answered 10/31/2003)
	What is the best selective medium to grow C. difficile from a stool specimen? Also, the best anaerobic transport system or incubation system (bag, jar, chamber)? Is the organism hard to culture? We plan to study our strains for relatedness and antibiotic susceptibility patterns.  (answered 08/04/2003)
	What is the best way to cryopreserve anaerobic bacteria ? (answered 07/25/2003)
	In female genital cultures, when is it appropriate /not appropriate to process specimens for anaerobic bacteria? (answered 06/19/2003)
	In a mixed aerobic/anaerobic culture, is there a rule of thumb regarding how many anaerobes should be worked up? If not all, then which ones - the gram neg bacilli, the predominant one(s), etc.? If not all, how should the report be worded (mixed anaerobic growth also present?). (answered 04/01/2003)
	1) Which protocol would you recommend for the isolation of Actinomyces spp. in case of heavily mixed anaerobic cultures ? 2) Should we count the number of colonies or just report the presence of Actinomyces spp. ? (answered 11/15/2002)
	My endodontist claims there are very few different causative agents of tooth abcesses and that there are very few antibiotics available for treatment. His position is that culturing of the infectious agent and antimicrobial susceptibility testing is therefore unnecessary. Any comment? (answered 10/21/2002)

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