DOCSLIB.ORG

Special Bacteriology Basic Laboratory Tests

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Special Bacteriology Basic Laboratory Tests 2016 UNIVERZITA KOMENSKÉHO V BRATISLAVE JESSENIOVA LEKÁRSKA FAKULTA V MARTINE Jana KOMPANÍKOVÁ Martina NEUSCHLOVÁ Vladimíra SADLOŇOVÁ SPECIAL BACTERIOLOGY BASIC LABORATORY TESTS Preface Special Bacteriology – Basic Laboratory Tests is intended above all for medical students. The book includes standard procedures commonly used in microbiological laboratory. We have tried to present principles of laboratory tests to make them easier to understand. Authors Contents 1 STAPHYLOCOCCI ........................................................................................................ 5 1.1 GRAM STAIN ................................................................................................................... 7 1.2 STAPHYLOCOCCI - BLOOD AGAR CULTURE .................................................................... 7 1.3 CATALASE TEST ............................................................................................................... 8 1.4 MANNITOL SALT AGAR CULTURE ................................................................................... 9 1.5 COAGULASE TEST ......................................................................................................... 11 2 STREPTOCOCCI ........................................................................................................ 14 2.1 STREPTOCOCCI - GRAM STAIN ..................................................................................... 15 2.2 STREPTOCOCCI - BLOOD AGAR CULTURE ..................................................................... 16 2.3 STREPTOCOCCI - SEROLOGIC PROPERTIES TESTING ..................................................... 18 2.4 STREPTOCOCCI - PHYSIOLOGIC (BIOCHEMICAL) PROPERTIES TESTING ...................... 20 2.5 ANTISTREPTOLYSIN O (ASO) ......................................................................................... 21 2.6 C-REACTIVE PROTEIN (CRP) .......................................................................................... 22 3 NEISSERIA ............................................................................................................... 23 3.1 NEISSERIA - GRAM STAIN ............................................................................................. 23 3.2 NEISSERIA - BLOOD AGAR CULTURE ............................................................................. 24 3.3 NEISSERIA - CHOCOLATE AGAR CULTURE .................................................................... 25 3.4 NEISSERIA - BIOCHEMICAL PROPERTIES TESTING ........................................................ 26 4 HAEMOPHILUS ........................................................................................................ 30 4.1 HAEMOPHILUS - GRAM STAIN ..................................................................................... 31 4.2 HAEMOPHILUS – CULTIVATION ON BLOOD AGAR ....................................................... 32 4.3 HAEMOPHILUS - CULTIVATION ON CHOCOLATE AGAR .............................................. 32 4.4 X AND V FACTOR DISKS FOR DIFFERENTIATION OF HAEMOPHILUS SPECIES............... 33 4.5 QUELLUNG TEST ........................................................................................................... 35 5 ENTEROBACTERIACEAE ............................................................................................ 36 5.1 ENTEROBACTERIACEAE - GRAM STAIN ........................................................................ 37 5.2 BURRI´S INDIA INK METHOD (CAPSULE VISUALISATION) ............................................ 39 5.3 ENTEROBACTERIACEAE - CULTIVATION ON BLOOD AGAR........................................... 40 5.4 ENTEROBACTERIACEAE – CULTIVATION ON ENDO AGAR ............................................ 42 5.5 ENTEROBACTERIACEAE – CULTIVATION ON DEOXYCHOLATE CITRATE AGAR ........... 43 5.6 ENTEROBACTERIACEAE- BIOCHEMICAL PROPERTIES - TRIPLE SUGAR IRON AGAR (TSI, HAJN) .................................................................................................................... 44 5.7 UREASE TEST ................................................................................................................. 46 5.8 SIMMON´S CITRATE AGAR............................................................................................ 46 5.9 WIDAL REACTION ......................................................................................................... 47 5.10 BACTERIAL SEROTYPING ............................................................................................. 48 5.11 ENTEROTEST - PRINCIPLE ............................................................................................ 49 6 CAMPYLOBACTER, HELICOBACTER ........................................................................... 51 6.1 CAMPYLOBACTER JEJUNI .............................................................................................. 51 6.2 CAMPYLOBACTER - GRAM STAIN ................................................................................. 51 6.3 CAMPYLOBACTER - CULTIVATION ................................................................................ 51 6.4 HELICOBACTER PYLORI ................................................................................................. 52 6.5 HELICOBACTER - GRAM STAIN ..................................................................................... 52 6.6 HELICOBACTER - CULTIVATION .................................................................................... 53 6.7 UREASE TEST ................................................................................................................. 53 6.8 UREA BREATH TEST ...................................................................................................... 54 6.9 HELICOBACTER HEILMANNII ........................................................................................ 54 7 CORYNEBACTERIA ................................................................................................... 56 7.1 CORYNEBACTERIUM DIPHTERIAE ................................................................................. 56 7.2 CORYNEBACTERIA - GRAM STAIN................................................................................. 57 7.3 CORYNEBACTERIA – ALBERT STAIN (METACHROMATIC GRANULES) ......................... 58 7.4 CORYNEBACTERIA – CULTIVATION ON BLOOD AGAR ................................................. 59 7.5 CORYNEBACTERIA – CULTIVATION ON TELLURITE AGAR AND TINSDALE AGAR ......... 59 7.6 ELEK´S TEST ................................................................................................................... 60 8 BORDETELLA ........................................................................................................... 64 8.1 BORDETELLA PERTUSSIS ............................................................................................... 64 8.2 PERTUSSIS - SAMPLING ................................................................................................ 65 8.3 BORDETELLA PERTUSSIS – GRAM STAIN ...................................................................... 66 8.4 BORDETELLA PERTUSSIS – CULTIVATION(BORDET GENGOU BLOOD AGAR, CHARCOAL HORSE BLOOD AGAR) .................................................................................................. 66 9 ANAEROBIC BACTERIA .......................................................................................... 9-69 9.1 CLOSTRIDIA ................................................................................................................ 9-71 9.2 LABORATORY DIAGNOSIS OF ANAEROBIC BACTERIA ................................................ 9-73 9.3 ANAEROBIC INFECTIONS – SPECIMEN COLLECTION.................................................. 9-74 9.4 ANAEROBIC BACTERIA - GRAM STAIN ....................................................................... 9-74 9.5 ANAEROBIC BACTERIA – WIRTZ - CONKLIN STAIN .................................................... 9-77 9.6 ANAEROBIC BACTERIA - CULTIVATION ...................................................................... 9-78 10 SPIROCHETES .......................................................................................................... 83 10.1 TREPONEMA PALLIDUM ........................................................................................... 84 10.2 SYPHILIS .................................................................................................................... 85 10.3 SYPHILIS – LABORATORY TESTING ............................................................................ 86 10.4 TREPONEMA PALLIDUM - CULTIVATION .................................................................. 86 10.5 TREPONEMA PALLIDUM - MICROSCOPY .................................................................. 86 10.6 TREPONEMA PALLIDUM - SEROLOGICAL TESTS (NONTREPONEMAL AND TREPONEMAL TESTS) ............................................................................................................ 87 11 MYCOBACTERIA ...................................................................................................... 93 11.1 NONTUBERCULOUS MYCOBACTERIA – RUNYON CLASSIFICATION ......................... 93 11.2 MYCOBACTERIUM TUBERCULOSIS (TUBERCULOSIS) ............................................... 94 11.3 MYCOBACTERIUM TUBERCULOSIS – SAMPLE COLLECTION ................................... 96 11.4 MYCOBACTERIUM TUBERCULOSIS – ZIEHL-NEELSEN STAIN .................................... 97 11.5 MYCOBACTERIUM TUBERCULOSIS - CULTIVATION .................................................. 99
Load more

Recommended publications
  • Official Nh Dhhs Health Alert
    THIS IS AN OFFICIAL NH DHHS HEALTH ALERT Distributed by the NH Health Alert Network [email protected] May 18, 2018, 1300 EDT (1:00 PM EDT) NH-HAN 20180518 Tickborne Diseases in New Hampshire Key Points and Recommendations: 1. Blacklegged ticks transmit at least five different infections in New Hampshire (NH): Lyme disease, Anaplasma, Babesia, Powassan virus, and Borrelia miyamotoi. 2. NH has one of the highest rates of Lyme disease in the nation, and 50-60% of blacklegged ticks sampled from across NH have been found to be infected with Borrelia burgdorferi, the bacterium that causes Lyme disease. 3. NH has experienced a significant increase in human cases of anaplasmosis, with cases more than doubling from 2016 to 2017. The reason for the increase is unknown at this time. 4. The number of new cases of babesiosis also increased in 2017; because Babesia can be transmitted through blood transfusions in addition to tick bites, providers should ask patients with suspected babesiosis whether they have donated blood or received a blood transfusion. 5. Powassan is a newer tickborne disease which has been identified in three NH residents during past seasons in 2013, 2016 and 2017. While uncommon, Powassan can cause a debilitating neurological illness, so providers should maintain an index of suspicion for patients presenting with an unexplained meningoencephalitis. 6. Borrelia miyamotoi infection usually presents with a nonspecific febrile illness similar to other tickborne diseases like anaplasmosis, and has recently been identified in one NH resident. Tests for Lyme disease do not reliably detect Borrelia miyamotoi, so providers should consider specific testing for Borrelia miyamotoi (see Attachment 1) and other pathogens if testing for Lyme disease is negative but a tickborne disease is still suspected.
    [Show full text]
  • BD™ Baird-Parker Agar
    INSTRUCTIONS FOR USE – READY-TO-USE PLATED MEDIA PA-255084.04 Rev.: Sep 2011 BD Baird-Parker Agar INTENDED USE BD Baird-Parker Agar is a moderately selective and differential medium for the isolation and enumeration of Staphylococcus aureus in foods, environmental, and clinical specimens. PRINCIPLES AND EXPLANATION OF THE PROCEDURE Microbiological method. A variety of media is used for the isolation of Staphylococcus aureus, which plays a major role in food-poisoning and in human clinical infections. The formulation of the present Baird-Parker Agar was published in 1962.1 It is a partially selective medium which applies the ability of staphylococci to reduce tellurite to tellurium and to detect lecithinase from egg lecithin. Baird- Parker Agar is widely used and is included in many standard procedures for testing foods, cosmetics, or swimming pool waters for the presence of Staphylococcus aureus.2-6 It may also be used for the isolation of S. aureus from clinical specimens and is also called Egg- Tellurite-Glycine-Pyruvate Agar (ETGPA).7,8 BD Baird-Parker Agar contains the carbon and nitrogen sources necessary for growth. Glycine, lithium chloride and potassium tellurite act as selective agents. Egg yolk is the substrate to detect lecithinase production, and, in addition, lipase activity. Staphylococci produce dark gray to black colonies due to tellurite reduction; staphylococci that produce lecithinase break down the egg yolk and cause clear zones around respective colonies. An opaque zone of precipitation may form due to lipase activity. The medium must not be used for the isolation of staphylococci other than S. aureus.
    [Show full text]
  • Gst Gram Staining Learning Objectives the Student Will  Use Aseptic Techniques in the Safe Inoculation of Various Forms of Media
    GSt Gram Staining Learning Objectives The student will Use aseptic techniques in the safe inoculation of various forms of media. Follow oral and written instructions and manage time in the lab efficiently. Use the bright field light microscope to view microbes under oil immersion, make accurate observations and appropriate interpretations and store the microscope according to lab procedures. Properly prepare a bacterial smear for accurate staining and describe the chemical basis for simple staining and negative staining. Background/Theory Differential staining distinguishes organisms based on their interactions with multiple stains. In other words, two organisms may appear to be different colors. Differential staining techniques commonly used in clinical settings include Gram staining, acid-fast staining, endospore staining, flagella staining, and capsule staining. This link to the OpenStax Microbiology text provides more detail on these differential staining techniques. (OpenStax CNX, 2018) The Gram stain is a differential staining procedure that involves multiple steps. It was developed by Danish microbiologist Hans Christian Gram in 1884 as an effective method to distinguish between bacteria containing the two most common types of cell walls. (OpenStax CNX, 2018) One type consists of an inner plasma membrane and a thick outer layer of peptidoglycan. The other type consists of a double phospholipid Figure 1 Simplified structures of Gram negative cells (left) and Gram positive bilayer with a thin layer of cells (right) peptidoglycan between the two. The Gram Staining technique remains one of the most frequently used staining techniques. The steps of the Gram stain procedure are listed below and illustrated in Figure. (OpenStax CNX, 2018) 1.
    [Show full text]
  • Chocolate Agar Plate MP103 Intended Use for Isolation of Neisseria Gonorrhoeae from Chronic and Acute Gonococcal Infections
    Chocolate Agar Plate MP103 Intended use For isolation of Neisseria gonorrhoeae from chronic and acute gonococcal infections. Composition** Ingredients Gms / Litre Proteose peptone 20.000 Dextrose 0.500 Sodium chloride 5.000 Disodium phosphate 5.000 Agar 15.000 After sterilization Sterile Lysed blood (at 80°C) 50.000 Vitamino Growth Supplement (FD025) 2 vials Final pH ( at 25°C) 7.3±0.2 **Formula adjusted, standardized to suit performance parameters Directions Either streak, inoculate or surface spread the test inoculum (50-100 CFU) aseptically on the plate. Principle And Interpretation Neisseria gonorrhoeae is a gram-negative bacteria and the causative agent of gonorrhea, however it is also occasionally found in the throat. The cultivation medium for gonococci should ideally be a rich nutrients base with blood, either partially lysed or completely lysed. The diagnosis and control of gonorrhea have been greatly facilitated by improved laboratory methods for detecting, isolating and studying N. gonorrhoeae. Chocolate Agar Base, with the addition of supplements, gives excellent growth of the gonococcus without overgrowth by contaminating organisms. G.C. Agar (M434) can also be used in place of Chocolate Agar Base, which gives slightly better results than Chocolate Agar (4). The diagnosis and control of gonorrhea have been greatly facilitated by improved laboratory methods for detecting, isolating and studying N. gonorrhoea. Interest in the cultural procedure for the diagnosis of gonococcal infection was stimulated by Ruys and Jens (9), Mcleod and co-workers (8), Thompson (7), Leahy and Carpenter (1), Carpenter, Leahy and Wilson (2) and Carpenter (10), who clearly demonstrated the superiority of this method over the microscopic technique.
    [Show full text]
  • Iron Is an Essential Nutrient 4 Bacteria and Humans
    Abstract The bhuTUV and bhuO genes play vital roles in the ability of Brucella abortus to use heme as an iron source and are regulated in an iron-responsive manner by RirA and Irr by Jenifer F. Ojeda April, 2012 Dissertation Advisor: RM Roop II Department of Microbiology and Immunology Brucella abortus is a Gram negative intracellular pathogen that causes the zoonotic disease brucellosis. Antibiotic treatment for brucellosis in humans is prolonged and sometimes followed by relapses. Currently, the United States employs prevention of the illness in humans through cattle vaccinations, eliminating the bacterium in its natural host. Unfortunately, these vaccine strains cause the disease in humans, and Brucella research ultimately aims to identify new vaccine targets as well as alternative treatment options. Brucella abortus resides in the phagosomal compartment of the host macrophage where essential nutrients such as iron are limited. Most bacteria need iron, and within the macrophage, heme is a likely source of iron due to the breakdown of red blood cells by the host macrophage. Heme transporters in Gram negative bacteria are highly conserved, and include components for outer membrane, periplasmic, and cytoplasmic membrane transport. BhuA has been previously characterized as the outer membrane heme transporter of Brucella abortus and here we report that BhuT, BhuU, and BhuV (BhuTUV) are the periplasmic and cytoplasmic heme transport components and that they are required in order for Brucella abortus to transport heme as an iron source. Utilization of heme as an iron source requires the breakdown of heme into ferrous iron, carbon monoxide, and biliverdin by a heme oxygenase.
    [Show full text]
  • Update on Coagulase-Negative Staphylococci—What the Clinician Should Know
    microorganisms Review Update on Coagulase-Negative Staphylococci—What the Clinician Should Know Ricarda Michels †, Katharina Last † , Sören L. Becker and Cihan Papan * Institute of Medical Microbiology and Hygiene, Saarland University, 66424 Homburg, Germany; [email protected] (R.M.); [email protected] (K.L.); [email protected] (S.L.B.) * Correspondence: [email protected]; Tel.: +49-6841-16-23943 † These authors contributed equally to this work. Abstract: Coagulase-negative staphylococci (CoNS) are among the most frequently recovered bacteria in routine clinical care. Their incidence has steadily increased over the past decades in parallel to the advancement in medicine, especially in regard to the utilization of foreign body devices. Many new species have been described within the past years, while clinical information to most of those species is still sparse. In addition, interspecies differences that render some species more virulent than others have to be taken into account. The distinct populations in which CoNS infections play a prominent role are preterm neonates, patients with implanted medical devices, immunodeficient patients, and those with other relevant comorbidities. Due to the property of CoNS to colonize the human skin, contamination of blood cultures or other samples occurs frequently. Hence, the main diagnostic hurdle is to correctly identify the cases in which CoNS are causative agents rather than contaminants. However, neither phenotypic nor genetic tools have been able to provide a satisfying solution to this problem. Another dilemma of CoNS in clinical practice pertains to their extensive Citation: Michels, R.; Last, K.; Becker, antimicrobial resistance profile, especially in healthcare settings. Therefore, true infections caused by S.L.; Papan, C.
    [Show full text]
  • The Fine Structure of Diplococcus Pneumoniae
    THE FINE STRUCTURE OF DIPLOCOCCUS PNEUMONIAE ALEXANDER TOMASZ, Ph.D., JAMES D. JAMIESON, M.D., and ELENA OTTOLENGtII, M.D. From The Rockefeller Institute and the New York University School of Medicine, New York ABSTRACT The fine structure of an unencapsulated strain of Diplococcus pneumoniae is described. A strik- ing feature of thcsc bacteria is an intracytoplasmic membrane system which appears to be an extension of septa of dividing bactcria. The possible function of these structures and their relationship to the plasma membrane and other types of intracytoplasmic membranes found in pncumococcus is discussed. INTRODUCTION Our main interest in the fine structure of Diplo- walls. Throughout this paper, such preparations will coccus pneumoniae stems from the fact that these be referred to as "spheroplasts." bacteria readily undergo genetic transformation. The bacteria were fixed and stained according to the method of Ryter and Kellenberger (4), embedded Prior to undertaking electron microscope studies in cross-linked methacrylate, and sectioned with a on this process, the fine structure of pneumococcal Porter-Blum mlcrotome using a diamond knife. The cells in thin sections was examined. During the sections were stained with lead according to the preliminary stage of these studies on a transform- method of Karnovsky (5) (method B) and were able strain, we observed some unique membranous examined in the RCA electron microscopes models structures which, to the best of our knowledge, 2B, 3F, or in the Siemens Elmiskop I. have not previously been described in bacteria. RESULTS MATERIALS AND METHODS The nuclear region of pneumococcus resembles that Unencapsulated strains of Diplocoecus pneumoniae R6, of other bacteria prepared by the method of R1, and some nutritional mutants derived from R6 Ryter and Kellenberger (4).
    [Show full text]
  • Introduction to Bacteriology and Bacterial Structure/Function
    INTRODUCTION TO BACTERIOLOGY AND BACTERIAL STRUCTURE/FUNCTION LEARNING OBJECTIVES To describe historical landmarks of medical microbiology To describe Koch’s Postulates To describe the characteristic structures and chemical nature of cellular constituents that distinguish eukaryotic and prokaryotic cells To describe chemical, structural, and functional components of the bacterial cytoplasmic and outer membranes, cell wall and surface appendages To name the general structures, and polymers that make up bacterial cell walls To explain the differences between gram negative and gram positive cells To describe the chemical composition, function and serological classification as H antigen of bacterial flagella and how they differ from flagella of eucaryotic cells To describe the chemical composition and function of pili To explain the unique chemical composition of bacterial spores To list medically relevant bacteria that form spores To explain the function of spores in terms of chemical and heat resistance To describe characteristics of different types of membrane transport To describe the exact cellular location and serological classification as O antigen of Lipopolysaccharide (LPS) To explain how the structure of LPS confers antigenic specificity and toxicity To describe the exact cellular location of Lipid A To explain the term endotoxin in terms of its chemical composition and location in bacterial cells INTRODUCTION TO BACTERIOLOGY 1. Two main threads in the history of bacteriology: 1) the natural history of bacteria and 2) the contagious nature of infectious diseases, were united in the latter half of the 19th century. During that period many of the bacteria that cause human disease were identified and characterized. 2. Individual bacteria were first observed microscopically by Antony van Leeuwenhoek at the end of the 17th century.
    [Show full text]
  • Infection at the Wildlife-Livestock-Human Interface: Three Systems
    Infection at the Wildlife- livestock-human interface: three systems Thesis submitted in accordance with the requirements of the University of Liverpool for the degree of Doctor in Philosophy by Elsa Sandoval Barron 12/4/2017 Abstract Zoonoses involve interactions between at least three species: the pathogen and two hosts, one of which is human and the other a non-human (vertebrate) animal. More than 60% of human infectious diseases are zoonotic, and many have a wildlife host. Urbanisation and human population growth have increased the demand for food and land resources, which have increased interaction between humans, domestic animals and wildlife and thus the potential for cross-species transmission of infections. Most studies of such systems take place in tropical and developing countries where population change and biodiversity makes the emergence of high profile infections (eg Ebola and SARS) more likely. This study, however, focuses on four well known infections within the UK: bovine tuberculosis, water-borne cryptosporidiosis and giardiasis, and campylobacteriosis. The aim of this study was to investigate, using four infectious diseases of economic and public health importance in the UK as study systems, the role of wildlife in the epidemiology of multihost, zoonotic infections. Bovine tuberculosis (bTB) is an important zoonosis in many parts of the world, but human infection is rare in the UK owing to a policy of ‘test and cull’ in cattle and pasteurisation of milk. However, there has been an epidemic of bTB in British cattle in recent decades, the control of which is complicated by infection in badgers (Meles meles) and controversy over the control of wildlife infection.
    [Show full text]
  • Laboratory Exercises in Microbiology: Discovering the Unseen World Through Hands-On Investigation
    City University of New York (CUNY) CUNY Academic Works Open Educational Resources Queensborough Community College 2016 Laboratory Exercises in Microbiology: Discovering the Unseen World Through Hands-On Investigation Joan Petersen CUNY Queensborough Community College Susan McLaughlin CUNY Queensborough Community College How does access to this work benefit ou?y Let us know! More information about this work at: https://academicworks.cuny.edu/qb_oers/16 Discover additional works at: https://academicworks.cuny.edu This work is made publicly available by the City University of New York (CUNY). Contact: [email protected] Laboratory Exercises in Microbiology: Discovering the Unseen World through Hands-On Investigation By Dr. Susan McLaughlin & Dr. Joan Petersen Queensborough Community College Laboratory Exercises in Microbiology: Discovering the Unseen World through Hands-On Investigation Table of Contents Preface………………………………………………………………………………………i Acknowledgments…………………………………………………………………………..ii Microbiology Lab Safety Instructions…………………………………………………...... iii Lab 1. Introduction to Microscopy and Diversity of Cell Types……………………......... 1 Lab 2. Introduction to Aseptic Techniques and Growth Media………………………...... 19 Lab 3. Preparation of Bacterial Smears and Introduction to Staining…………………...... 37 Lab 4. Acid fast and Endospore Staining……………………………………………......... 49 Lab 5. Metabolic Activities of Bacteria…………………………………………….…....... 59 Lab 6. Dichotomous Keys……………………………………………………………......... 77 Lab 7. The Effect of Physical Factors on Microbial Growth……………………………... 85 Lab 8. Chemical Control of Microbial Growth—Disinfectants and Antibiotics…………. 99 Lab 9. The Microbiology of Milk and Food………………………………………………. 111 Lab 10. The Eukaryotes………………………………………………………………........ 123 Lab 11. Clinical Microbiology I; Anaerobic pathogens; Vectors of Infectious Disease….. 141 Lab 12. Clinical Microbiology II—Immunology and the Biolog System………………… 153 Lab 13. Putting it all Together: Case Studies in Microbiology…………………………… 163 Appendix I.
    [Show full text]
  • Francisella Tularensis 6/06 Tularemia Is a Commonly Acquired Laboratory Colony Morphology Infection; All Work on Suspect F
    Francisella tularensis 6/06 Tularemia is a commonly acquired laboratory Colony Morphology infection; all work on suspect F. tularensis cultures .Aerobic, fastidious, requires cysteine for growth should be performed at minimum under BSL2 .Grows poorly on Blood Agar (BA) conditions with BSL3 practices. .Chocolate Agar (CA): tiny, grey-white, opaque A colonies, 1-2 mm ≥48hr B .Cysteine Heart Agar (CHA): greenish-blue colonies, 2-4 mm ≥48h .Colonies are butyrous and smooth Gram Stain .Tiny, 0.2–0.7 μm pleomorphic, poorly stained gram-negative coccobacilli .Mostly single cells Growth on BA (A) 48 h, (B) 72 h Biochemical/Test Reactions .Oxidase: Negative A B .Catalase: Weak positive .Urease: Negative Additional Information .Can be misidentified as: Haemophilus influenzae, Actinobacillus spp. by automated ID systems .Infective Dose: 10 colony forming units Biosafety Level 3 agent (once Francisella tularensis is . Growth on CA (A) 48 h, (B) 72 h suspected, work should only be done in a certified Class II Biosafety Cabinet) .Transmission: Inhalation, insect bite, contact with tissues or bodily fluids of infected animals .Contagious: No Acceptable Specimen Types .Tissue biopsy .Whole blood: 5-10 ml blood in EDTA, and/or Inoculated blood culture bottle Swab of lesion in transport media . Gram stain Sentinel Laboratory Rule-Out of Francisella tularensis Oxidase Little to no growth on BA >48 h Small, grey-white opaque colonies on CA after ≥48 h at 35/37ºC Positive Weak Negative Positive Catalase Tiny, pleomorphic, faintly stained, gram-negative coccobacilli (red, round, and random) Perform all additional work in a certified Class II Positive Biosafety Cabinet Weak Negative Positive *Oxidase: Negative Urease *Catalase: Weak positive *Urease: Negative *Oxidase, Catalase, and Urease: Appearances of test results are not agent-specific.
    [Show full text]
  • MYCOBACTERIA.Pdf
    MYCOBACTERIA Mycobacteria are widespread organisms, typically living in and food sources. Tuberculosis and the leprosy organisms are obligate parasites and are not found as free-living members of the genus. Mycobacteria are aerobic and nonmotile bacteria (except for the species Mycobacterium marinum, which has been shown to be motile within macrophages) that are characteristically acid fast. Mycobacteria have an outer membrane. They do not have capsules, and most do not form endospores. The distinguishing characteristic of all Mycobacterium species is that the cell wall is thicker than in many other bacteria, which is hydrophobic, waxy, and rich in mycolic acids/mycolates. The cell wall consists of the hydrophobic mycolate layer and a peptidoglycan layer held together by a polysaccharide, arabinogalactan. The cell wall makes a substantial contribution to the hardiness of this genus. The biosynthetic pathways of cell wall components are potential targets for new drugs for tuberculosis. Fig. 1 Mycobacterial cell wall: 1-outer lipids, 2-mycolic acid, 3-polysaccharides (arabinogalactan), 4-peptidoglycan, 5-plasma membrane, 6-lipoarabinomannan (LAM), 7- phosphatidylinositol mannoside, 8-cell wall skeleton. NONTUBERCULOUS MYCOBACTERIA – RUNYON CLASSIFICATION Runyon classification is a system of identifying mycobacteria on the basis of pigmentation and growth condition of the organisms. The Runyon classification of nontuberculous mycobacteria based on the rate of growth, production of yellow pigment and whether this pigment was produced in the dark or only after exposure to light. It was introduced by Ernest Runyon in 1959 (Fig. 111). On these bases, the nontuberculous mycobacteria are divided into four groups: Photochromogens (Group I) - produce nonpigmented colonies when grown in the dark and pigmented colonies only after exposure to light and reincubation (1M.
    [Show full text]