Clinical Microbiology

2008

Microorganisms as causative agents of infections in animals Companion animals:

Dog and cat Horse

Food animals Cattle and sheep Pig Poultry

Infections of the.. Respiratory system Nervous system (CNS) Gastro-intestinal tract Urinary tract Genital systém Skin, soft tissues and wounds Joint and bones

Clinical microbiology (microbes and antimicrobials) Bacteriology

and use of antibiotics and chemoterapeutics)

Virology And use of antivirotics

Mycology And use of antimycotics

Use of vaccines

Clinical specimens Colleted from living animals not

from necropsy

Characterisation of bacteria from clinical specimens Processing of a specimen

Gram stain Cultivation

Atmosphere (A/AN, A+CO2,AN,A) Culture media (solid:BA, MC agar,XLD agar,

chocolate agar, liquid: broths) Identification

G+ Gram- negative bacteria (oxidase, catalase,

biochemical tests, serological tests to identify serovars

Further identification -Typing methods

Serological tests are used for serotyping (E.coli O157 H7, E. coli O141 F4 S. Typhimurium O 1,4,5,12,H: i, 1,2 S. Enteritidis O1,9,12, H:g,m

Bacteriophage typing (S. Typimurium DT 104)

Identification – subtyping methods DNA subtyping methods gene typing for virulence factors

instead of toxin production E.coli P. multocida

Obligate anaerobic bacteria Bacteroides/Fusobacterium Porphyromonas Prevotella Clostridium perfringens Clostridium difficile

Metods for detection of non-cultured bacteria Microscopy PCR detection using various

modifications PCR Nested PCR Real time PCR

Non-cultured bacterial genera and species Lawsonia intracellularis Chlamydophilla spp. Rickketsias Hemomycoplasmas:

Mycoplasma hemosuis, M. hemofelis

G- bacterial species most frequently obsereved Psudomonas aeruginosa E. coli Other coliforms (Klebsiella,

Enterobacter) Salmonella Pasteurella multocida Haemophilus spp. Actinobacillus spp.

G+ bacterial species most frequently obsereved Beta – haemolytic streptococci Staphylococcus

aureus/S.intermedius Coagulase negative staphylococci Enterococci Clostridium perfringens

Zoonotic bacterial species Campylobacter jejuni, C.coli VTEC (verotoxigenic E.coli

serogroup O157 Salmonella enterica (ST DT 104) Yersinia enterocolitica Streptococcus suis 2 Listeria moncytogenes

Mycotic infections Candida albicans

Dermatophyta

Use of Antibiotics Antibiotic susceptibility testing MIC – minimum inhibitory

concentrations Disc susceptibility test Etest Beta-lactamase test

Commonly used antibiotic Range of action:

Very good Good Poor activity against particular

bacteria Bacterial resistance mechanisms

Betalactams

PENICILLINS Benzylpenicillin Aminopenicillins

Ampicilin, amoxicilin

Cephalosporines 1 to 4 generation

1g: cephalotin 2g: cefuroxim 3g: ceftazidim 4g: cefquinom

Carbapenems Imipenem

Inhibitors of beta-lactamases Clavulanic acid Sulbactam

Combination: co-amoxicillin

Glykopeptides Vancomycin Teicoplanin

Aminoglycosides Streptomycin Gentamicin

Macrolides Erytromycin Tylosin Tilmicosin

Lincosamides Lincomycine

Tetracyclines Oxytetracycline/Chlortetracycline

Doxycycline

Amphenicols Chloramphenicol

2.gen. Florfenicol

Pleuromutilins (diterpens) Tiamulin 2gen. Valnemulin

Chemoterapeutics Sulfonamides

Quinolones

Sulfonamides Sulfamethoxazol

Co- trimoxazol

Quinolones Non fluorinated q.

Oxolinic acid

Fluorinated q. enrofloxacin

Infections of the Respiratory System Mirobes Pathogenesis (aspiration)

Nasopharynx Pharynx (pharyngitis) Trachea Bronchi (bronchioli) Lungs -pneumonia Bronchopneumonia Pleura (pleuritis) Lung absces

Infection of the skin and sof tissues A breatch of the skin

Via minor abrasions Hair follicles Surgical incision Wounds (traumatic, surgical)

Infections of the blood Bacteraemia - bacteria in the blood

se detected by blood culture Transient (single episode) Intermittent Continuous