Media - Microbiology Techniques PDF

140 Media Routine Media Special Media MEDIA PURPOSE MEDIA...

140 Media Routine Media Special Media MEDIA PURPOSE MEDIA PllRPO'-f Blood A~ar Most Bacteria; Determines Bordet-Gengou Agar 8. pertussis (BA, BA ) Hemolytic Reactions Buffered Charcoal Legionella sp. Chocolate Agar Haemophilus and Neisseria sp.; Yeast Extract (BCYE) Enriched with Hemoglobin or lsoVitalleX Cystine-Glucose Agar F. tularensis Phenylethyl Alcohol Selects for Gram Positive Cocci and Fletcher's Medium leptospira Agar (PEA) Anaerobic Gram Negative Bacilli Skirrow Agar Helicobacter pylori Columbia Colistin- Selects for Gram Positive Cocci Nalidixic Acid (CNA) Thiosulfate Citrate-Bile Vibrio sp. Salts Sucrose (TCBS) Vaginal is Agar (V-Agar) Cardnere/la vagina/is Thayer-Martin Agar N. gonorrhoeae and N meningitidis (human blood) CAMPY-Blood Agar Campylobacter sp. Cystine-Tellurite Blood C. diphtheriae (Black Colonies) Thioglycolate Broth "Back-Up" for Anaerobes (Tinsdale) Lowenstein-Jensen Mycobacterium sp. Loeffler's Medium C. diphtheriae (Enhances Grouping Agar and Metachromatic Granules) Middlebrook 7H10 Mycobacterium sp. Agar Select Biochemical Reactions Petragnani Agar Mycobacterium sp. Biochemical Test Uni nocu lated Positive Medium Color or Negative Reaction Reaction Anaerobic Media Carbohydrate Red Yellow MEDIA PURPOSE ferrnenatation with phenol red Bacteroides Bile Selects for B. fragilis Group Esculin Agar (BBE) (Black Colonies) Esculin Nondescript Black Kanamycin- Bacteroides sp. Hippurate No change Purple Vancomd1cin Laked (Enhances Pigment Production) hydrolysis Bloo (KVLB) Motility Growth along Blurred stab Cycloserine-Cefoxitin C. difficile stab line line Fructose Agar (CCFA) 6.5% NaCl Broth Clear Turbid CDC Anaerobic Blood Anaerobes (Enriched with Hemin, Phenylalanine or Nondescript Green Agar Cystine, and Vitamin K) trytophan surface after Cooked or Chopped Anaerobes deaminase 10% FeCl3 Meat Medium Urea Nondescript Bright pink COLD EIIRiCHIIENf Listeria monocytogenes Yersinia Anaerobic Media and Associated Organisms Special Media and Associated Organisms Especially Legionella  141 Specimen Collection and Handling GENERAL 1. Material from infection site CoHecti.on and Handling of 2. Optimal time (ex.: Salmonella typhi- Blood Culture Specimem1 culture blood ffrst week, culture stool second and third weeks) Diagnostic Methods 3. Appropriate collection devices MICROSCOPY 4. NEVER refrigerate spinal fluids, 1. Light microscopy anaerobic or GC specimens a. Resolving power - 0.2 µm b. Ocular lens= l0X; oil immersion 5. Collect prior to antibiotic therapy lens= IO0X 6. Set up within 2 hours of collection 2. Darkfield - for spirochetes; reflected CRITERIA FOR REJECTION light 1. Preservatives used 3. Fluorescence - near UV range; auramine rhodamine, acridine orange 2. Insufficient quantity and calco-fluor white stains 3. Dry swab 4. Electron microscopy - can resolve 4. Leaky containers - contaminated particles 0.001 µm apart; u seful in viral specimen as well as biohazard I.D. BLOOD CULTURE COLLECTION CULTURE CONDITIONS 1. Must prep skin properly with alcohol 1. Most plates incubated at 35-37°C (70%) and iodine a. Campylobacter - 42°C b. Yersinia - 25-30°C 2. Best time to draw is just prior to fever c. 5-10% CO2 (Campy- spike mi.croaeropl1ilic) d. 50-70% humidity 3. Draw at least 2 cultures, but no more than 3 in a 24 hr period 2. Anaerobic Conditions a. Broths with thioglyco.llate or 4. May use antibiotic removal device (ARD) cysteine or resin bottles if patient on antil1iotics b. P re-reduced media ❖ Gas pak jars or anaerobic 5. Isolator® best for fungi and acid fast chamber organisms ❖ Environment: 10% H2, 5% CO2, 6. Need 1: 10 dilution of blood to broth; 85% N2, palladium crystals on adults draw at least 10 ml (5ml for MEDIA pediatric bottles) 1. Approximately 1.5% agar 2. Non-selective a. Supports most organism s b. Blood agar, chocolate agar, trypticase soy agar 3. Selective agar a. Contains chemicals, dyes, antibiotics to inhibit certain organisms (EMB, MAC, CNA, Campy-blood) b. May also be differential (HE, SS, XLD, EMB, MAC)