01_bakteri Yang Penting Dlm Medis
-
Upload
silky-nazmatullaila -
Category
Documents
-
view
220 -
download
0
Transcript of 01_bakteri Yang Penting Dlm Medis
-
7/28/2019 01_bakteri Yang Penting Dlm Medis
1/30
Bacteria of Medical
Importance
Foundation Course
Prof V. O. Rotimi
-
7/28/2019 01_bakteri Yang Penting Dlm Medis
2/30
Objectives
At the end of this lecture the students should
be able to:
Recall the characteristics of a bacteriumGrasp the basis of classification of
bacteria of medical importance
Name important bacteria of clinicalimportance
Give examples of the infection they cause
Understand the basis of lab investigation
-
7/28/2019 01_bakteri Yang Penting Dlm Medis
3/30
General characteristics
Single cell prokaryotes
DNA forms a long circular molecule, notcontained in a defined nucleus
May or may not be motile or encapsulatedContains a complex cell wall
Reproduce by binary fission
Wide range of metabolic patterns, aerobic andanaerobic
Uses phenotypic and genotypic data forclassification
-
7/28/2019 01_bakteri Yang Penting Dlm Medis
4/30
-
7/28/2019 01_bakteri Yang Penting Dlm Medis
5/30
Classification
Distinguished by morphology and staining
reaction
Gram stain separates most bacteria into 2
great divisions:
Gram-positive bacteria
Gram-negative bacteria
-
7/28/2019 01_bakteri Yang Penting Dlm Medis
6/30
-
7/28/2019 01_bakteri Yang Penting Dlm Medis
7/30
Classification
Main structural component of cell wall is
PEPTIDOGLYCAN(mucopeptide or murein)
Gram-positive
Peptidoglycan is a thick layer external to the cellmembrane
Gram-negative
Peptidoglycan is thin and covered by an outer
membrane (OM)
Molecules of OM lipopolysaccharide & lipoprotein
-
7/28/2019 01_bakteri Yang Penting Dlm Medis
8/30
True bacteria
Classified on the basis of shape:
Cocci spherical
Bacilli relatively straight, rod-shaped
Vibrios curved rods
Spirochaetes - twisted filamentous rod-shaped
-
7/28/2019 01_bakteri Yang Penting Dlm Medis
9/30
Gram-stained bacteria
Gram-positive cocci Clusters
Chains
Pairs
Gram-positive bacilli (rods) Short, long, branched, twisted
Gram-negative cocci
Gram-negative bacilli
-
7/28/2019 01_bakteri Yang Penting Dlm Medis
10/30
Metabolic classification
Aerobes
Utilizes oxygen for respiration
Facultative aerobes
Survives with or without O2
Anaerobes
Cannot survive in the presence of O2
-
7/28/2019 01_bakteri Yang Penting Dlm Medis
11/30
-
7/28/2019 01_bakteri Yang Penting Dlm Medis
12/30
Aerobic Gram-positive cocci
S. pneumoniae
Viridans streptococci
Pneumonia, meningitis,
septicemia, septic shock,
acute otitis media
Infective endocarditis
(IE), abscesses, dental
caries
-
7/28/2019 01_bakteri Yang Penting Dlm Medis
13/30
-
7/28/2019 01_bakteri Yang Penting Dlm Medis
14/30
Gram-positive cocciAnaerobic
Peptostreptococcus
(anaerobic cocci)
Peptococcus
Lower respiratory
tract infections
Female genitaltract infections
Post-operative
wound infections
Brain abscess
-
7/28/2019 01_bakteri Yang Penting Dlm Medis
15/30
-
7/28/2019 01_bakteri Yang Penting Dlm Medis
16/30
Aerobic Gram-positive bacilli
Listeria
L. monocytogenes
Mycobacterium M. tuberculosis
MOTT
Neonatal sepsis,meningitis
Tuberculosis (atypicalpneumonia), spinalosteomyelitis, brainabscess
Atypical pneumonia inimmunocompromized pts
-
7/28/2019 01_bakteri Yang Penting Dlm Medis
17/30
Aerobic Gram-negative bacilli
Enterobacteriaceae
E. coli
Klebsiella spp.
Enterobacter/Citrobacter spp
UTI, septicemia/septicshock, meningitis,
wound infection,diarrhea
UTI, pneumonia,
septic shockUTI, septicemia/septicshock
-
7/28/2019 01_bakteri Yang Penting Dlm Medis
18/30
-
7/28/2019 01_bakteri Yang Penting Dlm Medis
19/30
Aerobic Gram-negative bacilli
Brucella spp.
B. melitensis
B. abortus
Neisseria spp.
N. gonorrheae
N. meningitidis
Brucellosis Goats milk & cheese
Cows milk & cheese
Gonorrhoea
Meningitis
-
7/28/2019 01_bakteri Yang Penting Dlm Medis
20/30
Aerobic Gram-negative bacilli
Helicobacter
H. pylori
Campylobacter spp
C. jejuni
C. coli
Non-dyspesia
gastritis, duodenal
and gastric ulcers,cancer
Gastroenteritis
-
7/28/2019 01_bakteri Yang Penting Dlm Medis
21/30
Aerobic Gram-negative bacilli
Vibrios
V. cholerae
V. parahemolyticus
Legionella spp
L. pneumophila
Cholera
Food-poisoning
Legionnaires disease
(atypical pneumonia)
-
7/28/2019 01_bakteri Yang Penting Dlm Medis
22/30
Other Gram-negative bacteria -
Spirochetes
Treponema spp T. pallidum
T. pertenue
Borrelia spp. B. recurrentis
B. duttoni
B. burgdorferi
Leptospira spp.
Syphilis
Yaws
Epidemic relapsing fever
Endemic relapsing fever
Lyme disease
Leptospirosis
-
7/28/2019 01_bakteri Yang Penting Dlm Medis
23/30
Anaerobes
Cannot tolerate molecular oxygen
Lack superoxide dismutase
Requires low redox potential (Eh)
Measured in mV (-75 to -450 mV)
Resistant to aminoglycosides
Majority are sensitive to metronidazole
-
7/28/2019 01_bakteri Yang Penting Dlm Medis
24/30
-
7/28/2019 01_bakteri Yang Penting Dlm Medis
25/30
Anaerobic Gram-positive bacilli
Spore-forming:
Clostridium tetani
Cl. perfringens
Cl. difficile
Cl. botulinum
Tetanus
Food-poisoning, gas
gangrene, septic abortionCDAD: Antibiotic-
associated diarrhoea,
Antibiotic-associated
colitis,
Pseudomembranous
colitis
Botulism food-poisoning
-
7/28/2019 01_bakteri Yang Penting Dlm Medis
26/30
Anaerobic Gram-positive bacilli
Non-sporing:
Actinomyces
A. israelii
Propionibacterium
P. acnes
Actinomycosis: cervico-
facial, thoracic,
abdominal, cutaneous.
Acute/chronic prosthesesinfection, prostatitis, acne
-
7/28/2019 01_bakteri Yang Penting Dlm Medis
27/30
-
7/28/2019 01_bakteri Yang Penting Dlm Medis
28/30
-
7/28/2019 01_bakteri Yang Penting Dlm Medis
29/30
Laboratory diagnosis
Specimens
Collection
Transportation
Processing Gram-stain, ZN stain
Culture non-selective and selective media
Non-cultural techniques
Serology EIA, ELISA, Immunofluorescence
Molecular, e.g. PCR
-
7/28/2019 01_bakteri Yang Penting Dlm Medis
30/30