Microbiology in Clinical Practice (eBook)

D. C. Shanson (Autor)

eBook Download: EPUB

2014 | 2. Auflage
680 Seiten
Elsevier Science (Verlag)
978-1-4831-8369-5 (ISBN)

Infos

Microbiology in Clinical Practice presents the infections and syndromes caused by micro-organisms. It discusses the management of infective diseases and aetiological agents. It addresses the latex agglutination, immunofluorescent, monoclonal antibody, and nucleic acid probe investigations. Some of the topics covered in the book are the classification and pathogenicity of microbes; classification of bacteria; classification of viruses; classification of fungi; general principles of antimicrobial chemotherapy; antibiotic sensitivity tests; procedures in the laboratory for microbiological diagnosis; and the mode of action of antimicrobial drugs. The resistance to antimicrobial drugs are covered. The microbiological investigations of septicaemia are discussed. The text describes the human immunodeficiency virus infection and AIDS in infants. A study of the congenital immunodeficiency and impaired resistance to infection is presented. A chapter is devoted to the predisposing factors for anaerobic infections. Another section focuses on the infections of the central nervous system. The book can provide useful information to doctors, pathologists, neurologists, students, and researchers.

Inhalt

Front Cover 1
Microbiology in Clinical Practice 4
Copyright Page 5
Table of Contents 18
Foreword to First Edition 6
Preface to Second Edition 7
Preface to First Edition 8
'Priority' Reading in this Book for Medical Students 10
Abbreviations 14
Acknowledgements for Illustrations 16
SECTION A: General Principles 24
Chapter 1. Classification and pathogenicity of 
26 
CLASSIFICATION OF BACTERIA 26
CLASSIFICATION OF VIRUSES 30
CLASSIFICATION OF FUNGI 30
PATHOGENESIS: FACTORS AFFECTING THE 'VIRULENCE' AND SPREAD OF MICROBES 34
Appendix: Basic characteristics of some important bacterial pathogens 38
Chapter 2. Use of the microbiology laboratory—general principles 56
COLLECTION OF CLINICALLY RELEVANT SPECIMENS 56
PROVISION OF ESSENTIAL CLINICAL INFORMATION 57
PRIOR DISCUSSION WITH THE MICROBIOLOGIST 58
COLLECTION OF GOOD QUALITY SPECIMENS 58
TRANSPORT OF SPECIMENS TO THE LABORATORY 60
PROCEDURES IN THE LABORATORY FOR MICROBIOLOGICAL DIAGNOSIS 61
ANTIBIOTIC SENSITIVITY TESTS 67
Appendix 1: Some microbiological methods 68
Appendix 2: Basic virological investigations 69
Chapter 3. Antimicrobial chemotherapy—general principles 74
MODE OF ACTION OF ANTIMICROBIAL DRUGS 74
SPECTRUM OF ACTIVITY OF ANTIMICROBIAL AGENTS 75
GENERAL PRINCIPLES OF USE OF ANTIMICROBIAL DRUGS 78
PHARMACOKINETIC FACTORS 85
USE OF MICROBIOLOGICAL INVESTIGATIONS IN THE 
90 
ANTIBIOTIC ASSAYS 93
CAUSES OF FAILURE OF ANTIMICROBIAL CHEMOTHERAPY 97
RESISTANCE TO ANTIMICROBIAL DRUGS 98
ANTIBIOTIC PROPHYLAXIS 103
ANTIBIOTIC POLICIES 105
Appendix: Notes on antimicrobiological drugs including some 'new' antibiotics 106
SECTION B: 
144 
Chapter 4. Pyrexia of undetermined origin (PUO) 146
DEFINITION OF PUO 146
MAJOR CAUSES OF PUO 146
INFECTIVE CAUSES OF PUO 147
INVESTIGATION OF PUO 149
SPECIAL INVESTIGATIONS 153
Chapter 5. Septicaemia 161
CLINICAL FEATURES 161
CAUSATIVE ORGANISMS 161
MICROBIOLOGICAL INVESTIGATIONS OF SEPTICAEMIA 166
ANTIBIOTIC TREATMENT OF SEPTICAEMIA 167
PREVENTION OF SEPTICAEMIA 171
MELIOIDOSIS 171
Appendix: Instructions for the collection of conventional blood cultures (example at St Stephen's Hospital, London SW10, 1985) 172
Chapter 6. Opportunistic infections 174
'OPPORTUNIST' ORGANISMS 174
OPPORTUNISTIC CONDITIONS 182
DIAGNOSIS OF OPPORTUNISTIC INFECTIONS 183
TREATMENT OF OPPORTUNISTIC INFECTIONS 185
PREVENTION OF OPPORTUNISTIC INFECTIONS 188
Chapter 7. Obstetric, perinatal and neonatal infections 191
INFECTIONS IN PREGNANCY 191
PERINATAL INFECTIONS 192
NEONATAL AND CONGENITAL INFECTIONS 194
PUERPERAL SEPSIS AND POST-PARTUM PYREXIA 204
HUMAN IMMUNODEFICIENCY VIRUS INFECTION AND AIDS IN INFANTS 205
GYNAECOLOGICAL INFECTIONS 206
Chapter 8. Infections in children 208
RESPIRATORY TRACT INFECTIONS 208
SPECIFIC CHILDHOOD FEVERS 211
SOME OTHER INFECTIONS IN CHILDHOOD 223
CONGENITAL IMMUNODEFICIENCY AND IMPAIRED RESISTANCE TO INFECTION 225
IMMUNIZATION 229
Appendix: List of infectious diseases notifiable in Britain 236
Chapter 9. Anaerobic infections 238
DEFINITION OF AN ANAEROBE 238
CLASSIFICATION OF ANAEROBES 238
PREDISPOSING FACTORS FOR ANAEROBIC INFECTIONS 239
NON-SPORING ANAEROBIC INFECTIONS 240
CLOSTRIDIAL INFECTIONS 243
Chapter 10. Infections of the central nervous system 251
MENINGITIS 251
ENCEPHALITIS 273
CEREBRAL ABSCESSES 280
EXTRADURAL SPINAL ABSCESS 283
GUILLAIN-BARRÉ SYNDROME 284
ACUTE TRANSVERSE MYELOPATHY 284
CONGENITAL CENTRAL NERVOUS SYSTEM INFECTIONS 284
Chapter 11. 'ENT' and eye infections 287
EAR, NOSE AND THROAT INFECTIONS 287
EYE INFECTIONS 296
Chapter 12. Infections of the lower respiratory tract 303
NORMAL FLORA OF THE LOWER RESPIRATORY TRACT 303
ACUTE TRACHEO-BRONCHITIS 303
INFECTIVE EXACERBATIONS OF CHRONIC BRONCHITIS 303
INFLUENZA 306
PARA-INFLUENZA 310
PNEUMONIA 310
LEGIONNAIRES' DISEASE 322
ASPERGILLUS BRONCHO-PULMONARY DISEASES 325
FARMER'S LUNG 326
BRONCHIECTASIS 327
CYSTIC FIBROSIS 328
LUNG ABSCESS 329
EMPYEMA 330
Chapter 13. Mycobacterial and actinomycete infections 332
MYCOBACTERIAL INFECTIONS 332
TUBERCULOSIS 332
OPPORTUNIST MYCOBACTERIA 342
LEPROSY 344
ACTINOMYCETE INFECTIONS 348
Chapter 14. Infections of the gastro-intestinal tract 351
NORMAL FLORA OF THE GASTRO-INTESTINAL TRACT 351
WATER AS A VEHICLE OF INFECTION 351
ENTERIC FEVER 352
GASTRO-ENTERITIS AND FOOD POISONING 358
ACUTE DIARRHOEA IN CHILDHOOD 369
INFANTILE GASTRO-ENTERITIS 370
DYSENTERY 373
CHOLERA 377
GIARDIASIS 380
WINTER VOMITING DISEASE 381
TRAVELLER'S DIARRHOEA 381
TROPICAL SPRUE 381
BLIND LOOP SYNDROME 381
ANTIBIOTIC-INDUCED DIARRHOEA 381
PSEUDO-MEMBRANOUS COLITIS 382
MORE RECENTLY RECOGNIZED CAUSES OF GASTRO-INTESTINAL TRACT INFECTION 382
Chapter 15. Hepatic infections 385
VIRAL HEPATITIS 385
OTHER INFECTIVE CAUSES OF JAUNDICE 394
LIVER ABSCESS 394
Chapter 16. Skin infections and infestations 397
NORMAL FLORA OF SKIN 397
CAUSATIVE ORGANISMS 397
SKIN LESIONS ASSOCIATED WITH BACTERIAL INFECTION 401
TREATMENT 409
SKIN LESIONS ASSOCIATED WITH VIRAL INFECTION 411
SKIN LESIONS ASSOCIATED WITH FUNGAL INFECTIONS 412
SKIN LESIONS ASSOCIATED WITH PROTOZOA 418
SKIN LESIONS ASSOCIATED WITH WORM INFESTATIONS 418
SKIN LESIONS ASSOCIATED WITH INSECT INFESTATIONS 419
Chapter 17. 
423 
PATHOGENESIS 423
BONE INFECTIONS 424
JOINT INFECTIONS (SEPTIC ARTHRITIS) AND 'REACTIVE' ARTHRITIS 427
TREATMENT OF BONE AND JOINT INFECTIONS (NON-TUBERCULOUS) 431
TUBERCULOSIS OF BONES AND JOINTS 434
Chapter 18. 
436 
INFECTIVE ENDOCARDITIS 436
INFECTIVE MYOCARDITIS AND PERICARDITIS 450
Chapter 19. Infections of the 
453 
NORMAL FLORA OF THE URINARY TRACT 453
DEFINITION OF URINARY TRACT INFECTION 453
SIGNIFICANT BACTERIURIA 453
CLINICAL PATHOLOGICAL CATEGORIES 453
PATHOGENESIS 454
PREDISPOSING FACTORS 455
EFFECTS OF URINARY TRACT INFECTIONS 457
CAUSATIVE ORGANISMS 458
INVESTIGATION OF URINARY TRACT INFECTIONS 460
TREATMENT OF URINARY TRACT INFECTIONS 468
PREVENTION OF URINARY TRACT INFECTIONS 473
Chapter 20. 
475 
CAUSATIVE ORGANISMS 475
INCIDENCE OF SOME SEXUALLY TRANSMITTED DISEASES 476
BACTERIAL INFECTIONS 476
LYMPHOGRANULOMA VENEREUM (LGV) 489
NON-SPECIFIC URETHRITIS 489
PELVIC INFLAMMATORY DISEASE 491
VIRAL INFECTIONS 493
FUNGAL INFECTION 496
PROTOZOAL INFECTION 497
BALANITIS 497
ARTHROPOD INFESTATIONS 498
SUMMARY OF DIAGNOSTIC MICROBIOLOGICAL INVESTIGATIONS FOR PATIENTS ATTENDING WITH SUSPECTED SEXUALLY TRANSMITTED DISEASE 498
Chapter 21. AIDS and other diseases caused by 
501 
MOLECULAR GENETICS OF HIV 503
IMMUNOPATHOGENESIS OF AIDS AND LATENCY OF HIV INFECTION 504
CLINICAL-PATHOLOGICAL DEFINITION OF AIDS 504
EPIDEMIOLOGY 505
CLINICAL MANIFESTATIONS OF HIV INFECTION 508
REVISED 1987 DEFINITION OF AIDS 511
OPPORTUNISTIC INFECTIONS INDICATIVE OF AIDS AND THEIR MANAGEMENT 512
MICROBIOLOGICAL INVESTIGATION OF HIV INFECTION 521
INFECTION CONTROL PRECAUTIONS TO PREVENT TRANSMISSION OF HIV TO PATIENTS AND STAFF 522
DRUGS TO TREAT HIV INFECTION 525
FUTURE PROSPECTS 525
Appendix: The full definition of AIDS 526
Chapter 22. 
530 
DEFINITION 530
MODES OF TRANSMISSION 530
BACTERIAL ZOONOSES 532
RICKETTSIAL ZOONOSES 544
VIRAL ZOONOSES 546
CHLAMYDIAL ZOONOSES 550
FUNGAL ZOONOSES 551
PROTOZOAL ZOONOSES 551
WORM ZOONOSES 554
Chapter 23. Arthropod-borne infections and viral haemorrhagic fevers 556
ARTHROPOD VECTORS OF INFECTIOUS DISEASE 556
DISEASES TRANSMITTED BY ARTHROPOD VECTORS 557
ARTHROPOD-BORNE INFECTIONS IMPORTED INTO BRITAIN 557
VIRAL HAEMORRHAGIC FEVERS 566
Chapter 24. 
573 
CESTODES (TAPEWORMS) 573
NEMATODES (ROUNDWORMS) 578
FILARIAL NEMATODES 587
TREMATODES (FLUKES) 590
Chapter 25. 
596 
GENERAL CONSIDERATIONS 596
DIFFERENT TYPES OF HOSPITAL-ACQUIRED INFECTION 599
ORGANISMS CAUSING HOSPITAL-ACQUIRED INFECTIONS 600
HOSPITAL-ACQUIRED URINARY TRACT INFECTIONS 605
SURGICAL WOUND INFECTIONS 610
ACUTE LOWER RESPIRATORY TRACT INFECTIONS 618
INTENSIVE CARE UNITS AND HOSPITAL-ACQUIRED INFECTION 619
INFECTIVE HAZARDS OF INTRAVENOUS INFUSION THERAPY 621
TUBERCULOSIS, VIRAL HEPATITIS AND AIDS 624
Appendix: Typing of organisms and isolation procedures 627
Chapter 26. Disinfection and 
633 
DEFINITION OF TERMS 633
DISINFECTION 633
STERILIZATION 643
CSSD AND TSSU 648
Index 650

Textauszug

Chapter 1

Classification and pathogenicity of microbes

Publisher Summary

This chapter discusses the classification and pathogenicity of microbes. The microbial causes of human disease include viruses, chlamydiae, rickettsiae, mycoplasmas, bacteria, fungi, and protozoa. Viruses differ greatly from all the other microbes as they consist essentially of only nucleic acid surrounded by a protein coat and contain only one instead of two types of nucleic acid. Once inside human cells, the viruses remove the normal nuclear control of the cells to take over cellular metabolism for the synthesis of new virions. Chlamydiae and rickettsiae are also obligate intracellular parasites, have both DNA and RNA, and multiply by binary fission. Mycoplasmas, bacteria, and fungi can be cultured in cell-free media. Bacterial causes of disease are mainly lower bacteria that are unicellular. Multiplication is predominantly by asexual binary fission, although biological variation is facilitated in some species by sex, especially with Gram-negative species such as Escherichia coli. Only a few higher bacteria cause disease in man, such as Actinomycetes israelit, which are filamentous Gram-positive bacilli.

So, naturalists observe, a flea

Hath smaller fleas that on him prey;

And these have smaller fleas to bite ‘em,

And so proceed ad infinitum.

Jonathan Swift, On Poetry

The microbial causes of human disease include viruses, chlamydiae, rickettsiae, mycoplasmas, bacteria, fungi and protozoa. Basic features of these are included in Table 1.1. Arthropods and worms are discussed in later chapters.

Table 1.1

Classification of microbes

Viruses

DNA or RNA

+ (Virus takes over control of cell to synthesize new virions)

–

0·01–0·3

No

No

No

No

Host cell may show inclusions

Chlamydiae e.g. C. trachomatis, C. psittact)

DNA + RNA

+ (Multiplication by binary fission)

–

0·3

No

No

Yes

Yes (e.g. tetracyclines)

Host cell shows characteristic inclusions

Rickettsiae Coxiella (e.g. R. prowazeki)

DNA + RNA

+ (Multiplication by binary fission)

(Occasional exceptions)

0·3

Sometimes just visible by special stains

Rudimentary cell wall

Yes

Yes (e.g. tetracyclines)

‘Typhus’ transmitted by arthropods

Mycoplasmas (e.g. M. pneumoniae, M. hominis)

DNA +RNA

+ (Multiplication involves ‘elementary bodies

+

0·12–0·3

Sometimes just visible by special stains

No

Yes

Yes (e.g. tetracyclines)

Pleomorphic cells

Bacteria

DNA + RNA

±

+ (Multiplication by binary fission)

0·5–0·8 long

Yes

Yes (Muramic acid usually present)

Yes

Yes

Rigid cell wall

Fungi

DNA + RNA

+

+

Larger than bacteria (>5 long, >0·5 wide)

Yes

Yes Thicker than bacterial wall + contains sterol

Yes

No sensitive to anti-fungal drugs

Members of plant kingdom but no chlorophyll

Protozoa

DNA + RNA

± (Depends on particular species)

±

Larger than fungi

Yes

Yes

Yes

Not usually

Viruses differ greatly from all the other microbes as they consist essentially of only nucleic acid surrounded by a protein coat (capsid) and contain only one instead of two types of nucleic acid. Once inside human cells, the viruses remove the normal nuclear control of the cells to take over cellular metabolism for the synthesis of new virions. Chlamydiae and rickettsiae are also obligate intracellular parasites, have both DNA and RNA, and multiply by binary fission. Mycoplasmas, bacteria and fungi can be cultured in cell-free media unlike the above intracellular microbes.

Bacterial causes of disease are mainly ‘lower’ bacteria which are unicellular. Multiplication is predominantly by asexual binary fission although biological variation is facilitated in some species by ‘sex’, especially with Gram-negative species such as Escherichia coli. Only a few ‘higher’ bacteria cause disease in man, such as Actinomycetes israelii which are filamentous Gram-positive bacilli.

Protozoa pathogenic to man are divided into three main groups:

1. Sarcodina (amoebae), e.g. Entamoeba histolytica

2. Sporozoa, e.g. Plasmodium falciparum, Toxoplasma gondii

3. Mastigophora (flagellates), e.g. Trichomonas vaginalis, Giardia lamblia, Leishmania and Trypanosoma species

CLASSIFICATION OF BACTERIA

There are three main groups of bacteria:

1. Bacteria that are readily Gram-stained

2. Acid-fast bacilli

3. Spirochaetes

Bacteria that are Readily Gram-stained

These are classified into Gram-positive (blue-purple) or Gram-negative (pink-red) cocci or bacilli (Table 1.2).

Table 1.2

Simple classification of Gram-stainable bacterial pathogens

Practical details of the Gram-stain are given in the Appendix to Chapter 2, p. 45. After the application of the methyl violet dye, Gram-positive bacteria stain blue and this colour is retained in spite of decolourization with acetone (or alcohol). Gram-negative bacteria initially stain blue after the methyl violet is applied, but the colour is lost after the application of acetone (or alcohol). They then take up the pink counterstain (saffronin, methyl red or carbol fuchsin).

The reason for the difference in colour after Gram-staining is not fully understood, but it is probably related to the large amount of mucopeptide and teichoic acid in the cell walls of Gram-positive bacteria. The fact that Gram-positive bacteria are more acidic than Gram-negative bacteria may account for their greater affinity for a basic dye. Even more important may be the greater permeability of Gram-negative cell walls which allow the methyl violet-iodine dye complex to diffuse out after treatment with acetone more readily than the cell walls of Gram-positive bacteria.

Within each subgroup, there are aerobic or anaerobic examples. The majority of bacterial pathogens can grow either aerobically or anaerobically, i.e. they are ‘facultative anaerobes’ such as Staphylococcus aureus or Escherichia coli; in Table 1.2 these have been included as ‘aerobes’. There are a few bacterial species which are strict aerobes, such as Pseudomonas aeruginosa, which will not grow at all anaerobically. Some bacterial species are strict anaerobes, such as Clostridium tetani or Bacteroides fragilis, which will not grow at all aerobically.

Exceptional Gram-stainable bacteria include Legionella pneumophila and Borrelia vincenti. Legionella pneumophila requires prolonged staining with the counterstain to be seen in tissues, although it appears readily as Gram-negative bacilli in smears made from colonies on agar media. Borrelia vincenti is the only spirochaetal pathogen that is easily seen by a Gram-stain.

Acid-fast Bacilli

Mycobacterial species are not readily seen by a Gram-stain, although they are weakly Gram-positive bacilli. Ziehl-Neelsen or other acid-fast stains are required for staining these organisms which have cell walls containing abundant lipids. Examples include Mycobacterium tuberculosis and Mycobacterium leprae.

Spirochaetes

Spirochaetes are thin-walled spiralled flexible organisms which are motile by means of an axial filament. They are not seen in a Gram-stain (except B. vincenti), but may be seen either by dark-ground illumination microscopy, or in a silver stain under the light microscope. Borrelia spirochaetes in the blood may also be seen in a Giemsa stain.

The three groups of spirochaetes include:

1 Treponema

Spirochaetes with regular spirals, approximately 1 μm apart from each other, 5–15 μm long and about 0·2 μm wide, e.g. Treponema pallidum (cause of...

Produkt-Details

• Erscheint lt. Verlag: 28.6.2014
• Sprache: englisch
• Themenwelt: Sachbuch/Ratgeber ► Gesundheit / Leben / Psychologie ► Krankheiten / Heilverfahren
• Themenwelt: Medizin / Pharmazie ► Medizinische Fachgebiete
• Themenwelt: Naturwissenschaften ► Biologie
• Themenwelt: Technik
• ISBN-10: 1-4831-8369-6 / 1483183696
• ISBN-13: 978-1-4831-8369-5 / 9781483183695