CHAPTER © 2014 by McGraw-Hill Education. This is proprietary material solely for authorized instructor use. Not authorized for sale or distribution in any manner. This document may not be copied, scanned, duplicated, forwarded, distributed, or posted on a website, in whole or part. 46 Microbiology and Disease

© 2014 by McGraw-Hill Education. This is proprietary material solely for authorized instructor use. Not authorized for sale or distribution in any manner. This document may not be copied, scanned, duplicated, forwarded, distributed, or posted on a website, in whole or part Explain the medical assistant’s role in microbiology Describe how microorganisms cause disease Describe how microorganisms are classified and named Discuss the role of viruses in human disease Discuss the symptoms of HIV/AIDS and hepatitis Discuss the role of bacteria in human disease. Learning Outcomes

© 2014 by McGraw-Hill Education. This is proprietary material solely for authorized instructor use. Not authorized for sale or distribution in any manner. This document may not be copied, scanned, duplicated, forwarded, distributed, or posted on a website, in whole or part Learning Outcomes (cont.) 46.7 Discuss the role of protozoa in human disease Discuss the role of fungi in human disease Discuss the role of multicellular parasites in human disease Describe the process involved in diagnosing an infection Identify general guidelines for obtaining specimens.

© 2014 by McGraw-Hill Education. This is proprietary material solely for authorized instructor use. Not authorized for sale or distribution in any manner. This document may not be copied, scanned, duplicated, forwarded, distributed, or posted on a website, in whole or part Learning Outcomes (cont.) Carry out the procedure for transporting specimens to outside laboratories Describe two techniques used in the direct examination of culture specimens Carry out the procedure for preparing and examining stained specimens Carry out the procedure for culturing specimens in the medical office Describe how to perform an antimicrobial sensitivity determination.

© 2014 by McGraw-Hill Education. This is proprietary material solely for authorized instructor use. Not authorized for sale or distribution in any manner. This document may not be copied, scanned, duplicated, forwarded, distributed, or posted on a website, in whole or part Introduction Microorganisms –Everywhere in the environment –Cause disease if Pathogenic in nature Displaced from their natural environment Medical assistant –Identification of microorganisms –Proper collection techniques –Testing procedures –Quality control

© 2014 by McGraw-Hill Education. This is proprietary material solely for authorized instructor use. Not authorized for sale or distribution in any manner. This document may not be copied, scanned, duplicated, forwarded, distributed, or posted on a website, in whole or part Microbiology and the Role of the Medical Assistant Microbiology – study of microorganisms Microorganisms –Resident normal flora –Pathogens Medical assistant –Assist the physician –Preparing specimens

© 2014 by McGraw-Hill Education. This is proprietary material solely for authorized instructor use. Not authorized for sale or distribution in any manner. This document may not be copied, scanned, duplicated, forwarded, distributed, or posted on a website, in whole or part Apply Your Knowledge What role does the medical assistant play in relation to microbiology? ANSWER: The medical assistant may assist the physician in obtaining specimens, obtain specimens herself, prepare specimens for direct examination or transport to a reference laboratory, and possibly perform microbiologic procedures.

© 2014 by McGraw-Hill Education. This is proprietary material solely for authorized instructor use. Not authorized for sale or distribution in any manner. This document may not be copied, scanned, duplicated, forwarded, distributed, or posted on a website, in whole or part How Microorganisms Cause Disease Extensive variety of pathogens People normally are able to avoid infection Cause disease in variety of ways May remain localized or become systemic Transmitted directly or indirectly

© 2014 by McGraw-Hill Education. This is proprietary material solely for authorized instructor use. Not authorized for sale or distribution in any manner. This document may not be copied, scanned, duplicated, forwarded, distributed, or posted on a website, in whole or part Classification and Naming of Microorganisms Classification by structure –Subcellular –Prokaryotic –Eukaryotic Standardized naming –Genus ~ biologic classification –Species of organism ~ distinct type of microorganism

© 2014 by McGraw-Hill Education. This is proprietary material solely for authorized instructor use. Not authorized for sale or distribution in any manner. This document may not be copied, scanned, duplicated, forwarded, distributed, or posted on a website, in whole or part Classification and Naming of Microorganisms (cont.) Standardized naming –Genus Category of biologic classification Example – Staphylococcus –Species of organism Represents a distinct type of microorganisms Examples – Staphylococcus aureus and Staphylococcus epidermidis

© 2014 by McGraw-Hill Education. This is proprietary material solely for authorized instructor use. Not authorized for sale or distribution in any manner. This document may not be copied, scanned, duplicated, forwarded, distributed, or posted on a website, in whole or part Apply Your Knowledge 2.Describe the classifications of microorganisms and give an example of each. ANSWER: Microorganisms are classified as: Subcellular organisms – viruses Prokaryotic organisms – bacteria Eukaryotic organisms – protozoans, fungi, and parasites 1. How do microorganisms cause disease? ANSWER: Organisms cause disease by using nutrients needed by cells and tissues, damaging cells directly, causing to body’s defenses to attack the cell, or producing toxins.

© 2014 by McGraw-Hill Education. This is proprietary material solely for authorized instructor use. Not authorized for sale or distribution in any manner. This document may not be copied, scanned, duplicated, forwarded, distributed, or posted on a website, in whole or part Viruses Smallest known infectious agents Subcellular microorganism –Have only nucleic acid surrounded by a protein coat –Must live and grow in living cells of other organisms Hepatitis Virus

© 2014 by McGraw-Hill Education. This is proprietary material solely for authorized instructor use. Not authorized for sale or distribution in any manner. This document may not be copied, scanned, duplicated, forwarded, distributed, or posted on a website, in whole or part Significant Bloodborne Pathogens Medical assistants must understand –How HIV and hepatitis cause infection –Risk factors –Progression of the infections –Treatments –Special precautions

© 2014 by McGraw-Hill Education. This is proprietary material solely for authorized instructor use. Not authorized for sale or distribution in any manner. This document may not be copied, scanned, duplicated, forwarded, distributed, or posted on a website, in whole or part AIDS/HIV Infection HIV – virus HIV infection  AIDS The HIV virus destroys –Helper T cells –Neurons Patients develop opportunistic infections

© 2014 by McGraw-Hill Education. This is proprietary material solely for authorized instructor use. Not authorized for sale or distribution in any manner. This document may not be copied, scanned, duplicated, forwarded, distributed, or posted on a website, in whole or part AIDS/HIV Infection (cont.) Risk factors –Unprotected sexual activity –Sharing needles used by IV drug users –Passes from mother to fetus or infant Risk in the medical community –Percutaneous exposure –Mucocutaneous exposure

© 2014 by McGraw-Hill Education. This is proprietary material solely for authorized instructor use. Not authorized for sale or distribution in any manner. This document may not be copied, scanned, duplicated, forwarded, distributed, or posted on a website, in whole or part AIDS/HIV Infection (cont.) Progression of the infection –Initial infection ~ may occur years before symptoms –Incubation period Virus becomes inactive Lasts 8 to 15 years –Full-blown AIDS 200 or less helper T cells / mL blood Opportunistic infections and neurological deterioration

© 2014 by McGraw-Hill Education. This is proprietary material solely for authorized instructor use. Not authorized for sale or distribution in any manner. This document may not be copied, scanned, duplicated, forwarded, distributed, or posted on a website, in whole or part AIDS/HIV Infection (cont.) Diagnosis –Rapid HIV test –Confirmatory blood tests Enzyme-linked immunosorbent assay (ELISA) Western Blot Test Immunofluorescent antibody (IFA) –Positive results in two of three positive – accurate diagnosis –Home test available

© 2014 by McGraw-Hill Education. This is proprietary material solely for authorized instructor use. Not authorized for sale or distribution in any manner. This document may not be copied, scanned, duplicated, forwarded, distributed, or posted on a website, in whole or part AIDS/HIV Infection (cont.) Symptoms –Systemic –Respiratory –Oral –Gastrointestinal –Central nervous symptoms –Peripheral nervous systems –Skin-related –Kaposi’s sarcoma

© 2014 by McGraw-Hill Education. This is proprietary material solely for authorized instructor use. Not authorized for sale or distribution in any manner. This document may not be copied, scanned, duplicated, forwarded, distributed, or posted on a website, in whole or part AIDS/HIV Infection (cont.) Prevention –Sexual contact Avoid high-risk sexual activity Take safety precautions –IV drug use ~ avoid sharing or reusing needles –Medical procedures ~ Standard Precautions –Education ~ accurate information

© 2014 by McGraw-Hill Education. This is proprietary material solely for authorized instructor use. Not authorized for sale or distribution in any manner. This document may not be copied, scanned, duplicated, forwarded, distributed, or posted on a website, in whole or part AIDS/HIV Infection (cont.) Chronic disorders – early diagnosis and treatment key Drug Treatment –Goals –Treatment guidelines –Initiating treatment ~ delayed vs. early

© 2014 by McGraw-Hill Education. This is proprietary material solely for authorized instructor use. Not authorized for sale or distribution in any manner. This document may not be copied, scanned, duplicated, forwarded, distributed, or posted on a website, in whole or part Hepatitis Viral infection of the liver Hepatitis A –Fecal-oral route –Vaccine available Hepatitis B –Bloodborne –Vaccine available Hepatitis C –Bloodborne –Prevent spread Hepatitis D – occurs only in people infected with the HBV Hepatitis E – fecal- oral route

© 2014 by McGraw-Hill Education. This is proprietary material solely for authorized instructor use. Not authorized for sale or distribution in any manner. This document may not be copied, scanned, duplicated, forwarded, distributed, or posted on a website, in whole or part Hepatitis (cont.) Risk factors include –IV drug use –Travel –Hemophilia or receiving blood transfusions prior to implementation of screening –Hemodialysis –Multiple sexual partners or living with someone with Hepatitis B or C

© 2014 by McGraw-Hill Education. This is proprietary material solely for authorized instructor use. Not authorized for sale or distribution in any manner. This document may not be copied, scanned, duplicated, forwarded, distributed, or posted on a website, in whole or part Hepatitis (cont.) Risk in medical community Progress of the infection –Prodromal stage –Icteric, or jaundice, stage –Convalescent stage

© 2014 by McGraw-Hill Education. This is proprietary material solely for authorized instructor use. Not authorized for sale or distribution in any manner. This document may not be copied, scanned, duplicated, forwarded, distributed, or posted on a website, in whole or part Hepatitis (cont.) Symptoms –Jaundice –Decreased appetite –Fatigue –Nausea and vomiting –Joint pain / tenderness –Stomach pain –General malaise Diagnosis –Investigation of Risk factors Exposure incidents –Blood tests Antigen-antibody systems Determine stage of disease

© 2014 by McGraw-Hill Education. This is proprietary material solely for authorized instructor use. Not authorized for sale or distribution in any manner. This document may not be copied, scanned, duplicated, forwarded, distributed, or posted on a website, in whole or part Hepatitis (cont.) Preventive measures –Avoid contact with contaminated substances –Use Standard Precautions –Vaccination ~ HBV infections –HBIG for postexposure inoculation

© 2014 by McGraw-Hill Education. This is proprietary material solely for authorized instructor use. Not authorized for sale or distribution in any manner. This document may not be copied, scanned, duplicated, forwarded, distributed, or posted on a website, in whole or part Apply Your Knowledge Which statements are true and which are false? ____ Risk factors are the same for HBV and HCV. ___ Hepatitis A is spread via contaminated blood or body fluids. ____ Helper T cells are red blood cells and are a key component of immune system. ____ Percutaneous exposure occurs through a puncture wound or needlestick. Viruses are the smallest known pathogens. Viruses are a complex life form but can only live in another organism’s cells. ANSWER : F T T F the fecal-oral route. white blood cells Right! F T simple

© 2014 by McGraw-Hill Education. This is proprietary material solely for authorized instructor use. Not authorized for sale or distribution in any manner. This document may not be copied, scanned, duplicated, forwarded, distributed, or posted on a website, in whole or part Bacteria Single-celled prokaryotic organisms Reproduce rapidly Classification –Shape –Ability to retain dyes –Ability to grow with / without air –Biochemical reactions

© 2014 by McGraw-Hill Education. This is proprietary material solely for authorized instructor use. Not authorized for sale or distribution in any manner. This document may not be copied, scanned, duplicated, forwarded, distributed, or posted on a website, in whole or part Classification and Identification Shape –Coccus – spherical, round, or ovoid –Bacillus – rod-shaped –Spirillum – spiral-shaped –Vibrio – comma-shaped

© 2014 by McGraw-Hill Education. This is proprietary material solely for authorized instructor use. Not authorized for sale or distribution in any manner. This document may not be copied, scanned, duplicated, forwarded, distributed, or posted on a website, in whole or part Classification and Identification (cont.) Ability to retain certain dyes –Gram stain –Acid-fast stain Ability to grow in presence or absence of air –Aerobes –Anaerobes –Facultative Biochemical reactions – differentiation

© 2014 by McGraw-Hill Education. This is proprietary material solely for authorized instructor use. Not authorized for sale or distribution in any manner. This document may not be copied, scanned, duplicated, forwarded, distributed, or posted on a website, in whole or part Bacteria (cont.) Special groups of bacteria –Mycobacteria –Rickettsiae –Chlamydiae –Mycoplasmas Bacterial pathogens

© 2014 by McGraw-Hill Education. This is proprietary material solely for authorized instructor use. Not authorized for sale or distribution in any manner. This document may not be copied, scanned, duplicated, forwarded, distributed, or posted on a website, in whole or part Bacteria (cont.) Drug resistance –MRSA –VRE –VISA –VRSA –ESBLs –PRSP Risk factors –Elderly –Invasive procedures –Prior use of antimicrobials –Repeated contact with healthcare system –Severity of illness –Underlying conditions

© 2014 by McGraw-Hill Education. This is proprietary material solely for authorized instructor use. Not authorized for sale or distribution in any manner. This document may not be copied, scanned, duplicated, forwarded, distributed, or posted on a website, in whole or part Bacteria (cont.) Preventing antibiotic resistance in healthcare settings 1.Prevent infection 2.Diagnose and treat infection appropriately 3.Use antibiotics carefully 4.Prevent transmission of infections

© 2014 by McGraw-Hill Education. This is proprietary material solely for authorized instructor use. Not authorized for sale or distribution in any manner. This document may not be copied, scanned, duplicated, forwarded, distributed, or posted on a website, in whole or part Apply Your Knowledge How are bacteria classified and identified? ANSWER: They are classified by their shape, their ability to retain certain dyes, their ability to grow in the presence or absence of air and biochemical reactions. Good Job!

© 2014 by McGraw-Hill Education. This is proprietary material solely for authorized instructor use. Not authorized for sale or distribution in any manner. This document may not be copied, scanned, duplicated, forwarded, distributed, or posted on a website, in whole or part Protozoans Single-celled eukaryotic organisms Found in soil and water Leading cause of death in developing countries

© 2014 by McGraw-Hill Education. This is proprietary material solely for authorized instructor use. Not authorized for sale or distribution in any manner. This document may not be copied, scanned, duplicated, forwarded, distributed, or posted on a website, in whole or part Fungi Eukaryotic organisms with rigid cell wall Yeasts –Single-celled –Reproduce by budding Molds –Large, fuzzy, multi-celled organisms –Reproduce by spores

© 2014 by McGraw-Hill Education. This is proprietary material solely for authorized instructor use. Not authorized for sale or distribution in any manner. This document may not be copied, scanned, duplicated, forwarded, distributed, or posted on a website, in whole or part Multicellular Parasites Organisms that live on or in another organism –Use it for nourishment –Detrimental to host Parasitic worms Parasitic insects

© 2014 by McGraw-Hill Education. This is proprietary material solely for authorized instructor use. Not authorized for sale or distribution in any manner. This document may not be copied, scanned, duplicated, forwarded, distributed, or posted on a website, in whole or part Apply Your Knowledge Matching: ___ Yeast or mold ___ Tapeworm/lice Poor sanitation promotes spread ___ Single-celled, much larger than bacteria ___ reproduce by budding or spores ___ Found in soil and water A.Fungus B.Protozoan C.Multicellular parasite C B ANSWER: A B, C A B

© 2014 by McGraw-Hill Education. This is proprietary material solely for authorized instructor use. Not authorized for sale or distribution in any manner. This document may not be copied, scanned, duplicated, forwarded, distributed, or posted on a website, in whole or part How Infections Are Diagnosed 1.Examine the patient –Presumptive diagnosis –May or may not need additional tests 2.Obtain specimen(s) 3.Examine the specimen –Wet mount –Smear

© 2014 by McGraw-Hill Education. This is proprietary material solely for authorized instructor use. Not authorized for sale or distribution in any manner. This document may not be copied, scanned, duplicated, forwarded, distributed, or posted on a website, in whole or part How Infections Are Diagnosed (cont.) 4. Culture the specimen –Placed on a growth medium and allowed to incubate –Identifies microorganism 5. Determine antibiotic sensitivity 6. Treat the patient

© 2014 by McGraw-Hill Education. This is proprietary material solely for authorized instructor use. Not authorized for sale or distribution in any manner. This document may not be copied, scanned, duplicated, forwarded, distributed, or posted on a website, in whole or part Apply Your Knowledge What is the process for diagnosing an infection? ANSWER: There are six steps for diagnosis and treatment of an infection: 1.Examine the patient4. Culture the specimen 2.Obtain specimen(s)5. Determine sensitivity 3.Examine specimen directly6. Treat patient Super!

© 2014 by McGraw-Hill Education. This is proprietary material solely for authorized instructor use. Not authorized for sale or distribution in any manner. This document may not be copied, scanned, duplicated, forwarded, distributed, or posted on a website, in whole or part Specimen Collection Must be collected correctly Collection devices –Use container appropriate for specimen –Sterile swabs Collection and transport systems

© 2014 by McGraw-Hill Education. This is proprietary material solely for authorized instructor use. Not authorized for sale or distribution in any manner. This document may not be copied, scanned, duplicated, forwarded, distributed, or posted on a website, in whole or part Guidelines for Specimen Collection Avoid causing harm Collect from appropriate site Obtain specimen at correct time Use appropriate devices Obtain sufficient quantity Obtain specimen prior to therapy Label correctly Include requisition form

© 2014 by McGraw-Hill Education. This is proprietary material solely for authorized instructor use. Not authorized for sale or distribution in any manner. This document may not be copied, scanned, duplicated, forwarded, distributed, or posted on a website, in whole or part Specimen Collection (cont.) Throat culture specimens Urine specimens Sputum specimens Wound specimens

© 2014 by McGraw-Hill Education. This is proprietary material solely for authorized instructor use. Not authorized for sale or distribution in any manner. This document may not be copied, scanned, duplicated, forwarded, distributed, or posted on a website, in whole or part Transporting Specimens to an Outside Laboratory Three objectives –Follow proper collection procedures –Prevent deterioration of specimen –Protect anyone handling specimen Transportation methods –Regularly scheduled pickups –As-needed pickups –Mail ~ e tiologic agent label

© 2014 by McGraw-Hill Education. This is proprietary material solely for authorized instructor use. Not authorized for sale or distribution in any manner. This document may not be copied, scanned, duplicated, forwarded, distributed, or posted on a website, in whole or part ANSWER: They are to Avoid causing harm, discomfort, or undue embarrassment Collect from appropriate site Obtain specimen at correct time Use appropriate collection devices Obtain sufficient quantity of specimen Obtain specimen prior to the start of antimicrobial therapy Label specimen correctly. Apply Your Knowledge 2.What are the objectives for transporting a specimen to an outside laboratory? ANSWER: They are to follow proper collection procedures and use the proper collection device, prevent deterioration of the specimen during transport, and protect anyone that will handle the specimen from exposure. Impressive ! 1.What are the general guidelines for specimen collection?

© 2014 by McGraw-Hill Education. This is proprietary material solely for authorized instructor use. Not authorized for sale or distribution in any manner. This document may not be copied, scanned, duplicated, forwarded, distributed, or posted on a website, in whole or part Direct Examination of Specimens Enables physician to initiate treatment immediately Wet mounts –Quick identification of microorganisms –Determining motility KOH mounts –Potassium hydroxide dissolves keratin –Fungal infections

© 2014 by McGraw-Hill Education. This is proprietary material solely for authorized instructor use. Not authorized for sale or distribution in any manner. This document may not be copied, scanned, duplicated, forwarded, distributed, or posted on a website, in whole or part Preparation and Examination of Stained Specimens Prepare a smear on a glass slide Gram’s stain –Moderate-complexity test –Series of staining and washing steps –Iodine used to “set” stain ~ mordant –Gram-positive –Gram-negative

© 2014 by McGraw-Hill Education. This is proprietary material solely for authorized instructor use. Not authorized for sale or distribution in any manner. This document may not be copied, scanned, duplicated, forwarded, distributed, or posted on a website, in whole or part Apply Your Knowledge 1. What are the methods for preparing a slide for direct examination by the physician? ANSWER: Wet mount and KOH mount. 2. How does the examination of stained specimens facilitate patient care? ANSWER: Stained specimens enable the physician to provide a quick, tentative diagnosis and differentiate between types of infections.

© 2014 by McGraw-Hill Education. This is proprietary material solely for authorized instructor use. Not authorized for sale or distribution in any manner. This document may not be copied, scanned, duplicated, forwarded, distributed, or posted on a website, in whole or part Culturing Specimens in the Medical Office Place a sample of specimen on a culture medium –Medium ~ nutrients –Place in incubator for growth –A colony develops as microorganism multiplies

© 2014 by McGraw-Hill Education. This is proprietary material solely for authorized instructor use. Not authorized for sale or distribution in any manner. This document may not be copied, scanned, duplicated, forwarded, distributed, or posted on a website, in whole or part Culture Media Liquid, semisolid, or solid containing agar Types –Selective –Nonselective Special culture units

© 2014 by McGraw-Hill Education. This is proprietary material solely for authorized instructor use. Not authorized for sale or distribution in any manner. This document may not be copied, scanned, duplicated, forwarded, distributed, or posted on a website, in whole or part Inoculating a Culture Plate Transfer some of the specimen onto a culture plate Label the plate correctly Qualitative analysis – determination of type of pathogen Quantitative analysis – number of bacteria present in sample

© 2014 by McGraw-Hill Education. This is proprietary material solely for authorized instructor use. Not authorized for sale or distribution in any manner. This document may not be copied, scanned, duplicated, forwarded, distributed, or posted on a website, in whole or part Inoculating a Culture Plate (cont.) Qualitative Quantitative

© 2014 by McGraw-Hill Education. This is proprietary material solely for authorized instructor use. Not authorized for sale or distribution in any manner. This document may not be copied, scanned, duplicated, forwarded, distributed, or posted on a website, in whole or part Culturing Specimens (cont.) Incubating culture plates Interpreting cultures –Characteristics of colonies –Relative number –Changes to media around colonies

© 2014 by McGraw-Hill Education. This is proprietary material solely for authorized instructor use. Not authorized for sale or distribution in any manner. This document may not be copied, scanned, duplicated, forwarded, distributed, or posted on a website, in whole or part Determining Antimicrobial Sensitivity Appropriate antimicrobial An outside lab reports –Sensitive –Intermediate –Resistant Inoculate and place antimicrobial discs Incubate and evaluate

© 2014 by McGraw-Hill Education. This is proprietary material solely for authorized instructor use. Not authorized for sale or distribution in any manner. This document may not be copied, scanned, duplicated, forwarded, distributed, or posted on a website, in whole or part Apply Your Knowledge ANSWER: Selective culture media allows the growth of only certain kinds of bacteria. Unselective culture media support the growth of most organisms. 2.The office received a culture sensitivity report on a bacteria that said it was resistant to an antimicrobial. What does this mean? ANSWER: It means that the bacteria was not killed by the antimicrobial and that there was an overgrowth of the bacteria. 1.What is the process for culturing a specimen?

© 2014 by McGraw-Hill Education. This is proprietary material solely for authorized instructor use. Not authorized for sale or distribution in any manner. This document may not be copied, scanned, duplicated, forwarded, distributed, or posted on a website, in whole or part In Summary 46.1 As an office medical assistant, you may assist the physician with several microbiologic procedures that aid in diagnosing and treating infectious diseases Microorganisms can cause disease by using up nutrients or other materials needed by the cells and tissues they invade, damaging body cells, and producing toxins Microorganisms are classified on the basis of their structure. Specific microorganisms are named in a standard way.

© 2014 by McGraw-Hill Education. This is proprietary material solely for authorized instructor use. Not authorized for sale or distribution in any manner. This document may not be copied, scanned, duplicated, forwarded, distributed, or posted on a website, in whole or part In Summary (cont.) 46.4Viruses are among the smallest known infectious agents causing common diseases, including the common cold, influenza, chickenpox, croup, hepatitis, and warts The initial symptoms of AIDS are usually severe flu- like symptoms followed later by systemic, respiratory oral, gastrointestinal, nervous system, and skin complaints. The general symptoms of hepatitis include jaundice, diminished appetite, fatigue, nausea, vomiting, joint pain or tenderness, stomach pain, and general malaise.

© 2014 by McGraw-Hill Education. This is proprietary material solely for authorized instructor use. Not authorized for sale or distribution in any manner. This document may not be copied, scanned, duplicated, forwarded, distributed, or posted on a website, in whole or part In Summary (cont.) 46.6 Bacteria are single-celled prokaryotic organisms that reproduce very quickly Protozoans are single-celled eukaryotic organisms found in soil and water Fungi are eukaryotic organisms including molds and yeasts Multicellular parasites include roundworms, tapeworms, flatworms, ticks, lice, and mites.

© 2014 by McGraw-Hill Education. This is proprietary material solely for authorized instructor use. Not authorized for sale or distribution in any manner. This document may not be copied, scanned, duplicated, forwarded, distributed, or posted on a website, in whole or part In Summary (cont.) The steps involved in diagnosing an infection are to: examine the patient; obtain one or more specimens; examine the specimen directly either by wet mount or smear; culture the specimen; and determine the culture’s antibiotic sensitivity The general guidelines for obtaining specimens are to: –obtain the specimen with great care to avoid causing the patient harm, discomfort, or undue embarrassment; –collect the material from a site; –obtain the specimen at the proper time; –use appropriate collection devices; –obtain a sufficient quantity of the specimen; and –obtain the specimen before antimicrobial therapy begins.

© 2014 by McGraw-Hill Education. This is proprietary material solely for authorized instructor use. Not authorized for sale or distribution in any manner. This document may not be copied, scanned, duplicated, forwarded, distributed, or posted on a website, in whole or part In Summary (cont.) When transporting specimens to outside laboratories, the medical assistant should: –Follow proper collection techniques using specific containers provided by the laboratory; –Maintain the samples in a state as close to their original as possible; and –Protect anyone who handles a specimen container from exposure to potentially infectious material Direct examination of culture specimens is accomplished in two ways: wet mounts and KOH mounts.

© 2014 by McGraw-Hill Education. This is proprietary material solely for authorized instructor use. Not authorized for sale or distribution in any manner. This document may not be copied, scanned, duplicated, forwarded, distributed, or posted on a website, in whole or part In Summary (cont.) To prepare a stained specimen, the medical assistant must first prepare a smear, fix the sample to the slide so it does not wash off during the staining process, and follow a specific staining procedure To culture a specimen, the medical assistant should place a sample of the specimen on or in a specialized culture medium and allow it to grow in an incubator for 24 to 48 hours.

© 2014 by McGraw-Hill Education. This is proprietary material solely for authorized instructor use. Not authorized for sale or distribution in any manner. This document may not be copied, scanned, duplicated, forwarded, distributed, or posted on a website, in whole or part In Summary (cont.) Performing an antimicrobial sensitivity test involves taking a sample of the isolated pathogen, suspending it in a small amount of liquid medium, and streaking it evenly on the surface of a culture plate. Small disks of filter paper containing various antimicrobial agents are placed on top of the inoculated agar plate. The plate is then incubated at 37º C, and the results are evaluated the following day.

© 2014 by McGraw-Hill Education. This is proprietary material solely for authorized instructor use. Not authorized for sale or distribution in any manner. This document may not be copied, scanned, duplicated, forwarded, distributed, or posted on a website, in whole or part Each organism's environment, for the most part, consists of other organisms. ~ Kevin Kelly End of Chapter 46