#mportance
 Talaro
 
$
 Corynebacterium, Proprionibacterium,
 Bacillus 
, Mostly saprobic
, Source o" antibiotics
located centrally in the sporangium. The spores are highly
refractile to light and resistant to staining. 
 Bacillus cereus
, 3arge bloc4-shaped rods
, Central spores that deelop under all conditions except in the liing body
, /irulence "actors 0 polypeptide capsule and exotoxins
, ( types o" anthrax%  0 cutaneous 0 spores enter through s4in blac4 sore-
eschar5 least dangerous
 
, 3etter attac4s o" $881  0 esulted in only $$ cases o"
anthrax and "ie deaths
 0 Great disruption and concern
 
 
, Mortality o" untreated cutaneous anthrax is
;$8<&
and bacteremia& Pulmonary and cutaneous
anthrax occurred during the $881
 bioterrorist attac4 on the =S postal system&
 
 Bacillus cereus
, Common airborne and dustborne5 usual methods o" disin"ection and antisepsis are ine""ectie
, Gro7s in "oods spores surie coo4ing and reheating
, #ngestion o" toxin-containing "ood causes nausea omiting abdominal cramps and diarrhea5 $) hour duration
,  'o treatment
, 3arge >8&+ x 1&$-$&+ x 18 µm? gram-positie bacilli
7ith s@uare or concae ends containing endospores
that by GramAs stain appear as intracellular non-
staining >clear? ooid areas >spores do not stain by
crystal iolet sa"ranin or carbol"uchsin?
,  Bacillus becomes gram-ariable or gram-negatie
7ith aging in culture but unli4e true gram-negatie
 bacteria Bacillus susceptible to gro7th inhibition
 by a (8 Bg-ancomycin dis4 
 
MacCon4ey agar 
gram-positie rods positie "or catalase
strongly presumptie "or Bacillus
 
agar large >)-+ mm? "lat and 7hite to gray
7ith irregular edges and no β-hemolysis
, Colonies o" B& cereus large >(-6 mm? and
raised 7ith a gray to green "rosted-glass
appearance and undulate margins 7ith
distinct β-hemolysis
cipro"loxacin
, /accines
 0 lie spores and toxoid to protect liestoc4 
 0  puri"ied toxoid5 "or high ris4 occupations and
military personnel5 toxoid oer 1&+ years5
annual boosters
$#ORE&'OR"NG BA!((
Clinically important Clostridia are%
, 1$8 species
anaerobic conditions
, Cause 7ound in"ections tissue in"ections and
"ood intoxications
specimens&
rapidly5 o*ligate anaero*e.
, Produces dou*le ,ones of *eta hemolysis
 
$$$$
Clostridium perfringens , causes gas gangrene in damaged or dead tissues
, $nd most common cause o" "ood poisoning
7orld7ide
 0 toxins 0 alpha toxin 0 causes !C rupture edema
tissue destruction
 0 collagenase
 0 hyaluronidase
 0 :'ase
Alpha to+in
, 3yses !C platelets endothelial cells *!C and cause massie hemolysis tissue destruction hepatoxicity and hypotension&
Beta to+in
,  'umerous other toxins used to type C&  per"ringens&
 
$)
7hich leads to production o" gas in io
>crepitance?
, Collagenase
, yaluronidase
, :'ase
inoled in so"t tissue and 7ound in"ections -
myonecrosis
agina
 
$
Pathology
,  'ot highly inasie5 re@uires damaged and dead tissue and anaerobic conditions
, Conditions stimulate spore germination egetatie gro7th and release o" exotoxins and other irulence "actors&
 
7ounds decubitus ulcers compound "ractures
and in"ected incisions
, yperbaric oxygen therapy
large doses o" cephalosporin or penicillin
hyperbaric oxygen
yperbaric treatment
,  'ormal resident o" colon in lo7 numbers
, Causes antibiotic-associated colitis  0  relatiely non-inasie5 treatment 7ith broad-spectrum
antibiotics 4ills the other bacteria allo7ing C. difficile to oergro7
, Produces enterotoxins that damage intestines
, MaHor cause o" diarrhea in hospitals
, #ncreasingly more common in community ac@uired diarrhea
 
 seen ia a sigmoidoscope
electrolyte replacement and 7ithdra7al o"
antimicrobials&
or metronidaole and replacement cultures
, #ncreased precautions to preent spread
 
((((
Clostridium tetani , common resident o" soil G# tracts o" animals
, causes tetanus or loc4Ha7 a neuromuscular
disease
"rostbite crushed body parts
, accine booster needed eery 18 years
 
()
, Causes tetanus or loc4Ha7 a neuromuscular
disease
drug abusers5 neonates in deeloping countries
 
(+(+
inhibition o" s4eletal muscle contraction
 
(
, Spores usually enter through accidental puncture 7ounds burns umbilical stumps "rostbite and crushed  body parts&
, .naerobic enironment is ideal "or egetatie cells to gro7 and release toxin&
, Tetanospasmin 0 neurotoxin causes paralysis by  binding to motor nere endings5 bloc4ing the release o" neurotransmitter "or muscular contraction inhibition5 muscles contract uncontrollably
, :eath most o"ten due to paralysis o" respiratory muscles
 
and in"ection and maintaining homeostasis
, .ntitoxin therapy 7ith human tetanus immune
globulin5 inactiates circulating toxin but does
not counteract that 7hich is already bound
, Control in"ection 7ith penicillin or
tetracycline5 and muscle relaxants
years
1& "ood poisoning 0 >an intoxication? spores are in soil
may contaminate egetables5 improper canning does
not 4ill spores they germinate in the can producing
 botulinum toxin
acetylcholine
germinate in the body release toxin
(& 7ound botulism 0 spores enter 7ound cause "ood
 poisoning symptoms
, Clostridium perfringens 0 mild intestinal
illness5 second most common "orm o" "ood
 poisoning 7orld7ide
inade@uate "ood preseration
 
)(
, Spores are present on "ood 7hen gathered and  processed&
, #" reliable temperature and pressure are not achieed air 7ill be eacuated but spores 7ill remain&
, .naerobic conditions "aor spore germination and egetatie gro7th&
, Potent toxin *otulin is released&
, Toxin is carried to neuromuscular Hunctions and bloc4s the release o" acetylcholine necessary "or muscle contraction to occur&
, :ouble or blurred ision di""iculty s7allo7ing neuromuscular symptoms
 
))
"laccid paralysis
cause "ood poisoning symptoms
, :etermine presence o" toxin in "ood intestinal contents or "eces
, .dminister antitoxin5 cardiac and respiratory support
, #n"ectious botulism treated 7ith penicillin
 
)
Clostridial Gastroenteritis
, Clostrium perfringens
, Spores contaminate "ood that has not been coo4ed thoroughly enough to destroy spores&
, Spores germinate and multiply >especially i" unre"rigerated?&
, *hen consumed toxin is produced in the intestine5 acts on epithelial cells acute abdominal pain diarrhea and nausea
, apid recoery
diameter o" the rods in 7hich they are "ormed
, #n most species the spores are located centrally
subterminally or terminally& Most species o"
, Clostridia are motile 7ith peritrichous "lagella&
 
conditions& Fe7 are aerotolerant& .naerobic
conditions can be established by%
-& Agar plates or culture tu*es incu*ated in
anaero*ic 0ar1Gaspac2 0ar3.
fresh animal tissue1chopped coo2ed medium3 or
5.-6 agar and a reducing agent1fluid
thioglycolate3.
(eft. $tained pus from a mi+ed anaero*ic infection.
At least three different clostridia are apparent.
Right. Electron micrograph of Clostridium tetani 
C. botulinum
, 1-) "lagella
,  'o capsules
 bile
cytoplasm o" cells a"ter inducing phagocytosis5
aoids humoral immune system
 
+$+$
 0 $+-(8< o"
 
+(
macrophage
adhesion and penetration
, Can contaminate "oods and gro7 during re"rigeration
, (isteriosis & most cases associated 7ith dairy
 products poultry and meat
, #mmunocompromised patients "etuses and neonates5
a""ects brain and meninges
 0  $8< death rate
 process&
, .mpicillin and trimethoprimsul"amethoxaole
 
+
short chains
of hemolysis similar to Group B
$treptococcus
, Gro7s 7ell at 8&+J C to )+J C
, !ecause o" this temperature range especially the cooler end o" the range this organism gro7s 7ell in re"rigerated products such as cream cheese deli meats etc&
 
 0  Motility% , "otile at 4o !9
;um*rella; type <
, Tum*ling motility in hanging drop preparations 1this can *e seen on Gram $tain Tutor at 888.medtraining.org3
“Umbrella” motility pattern (Left)
typical for L. monocytogenes
hemolysis in contrast to
=arro8>&shape produced *y
animals and the enironment
, Primary reseroir 0 tonsils o" healthy pigs
, Enters through s4in abrasion multiples to
 produce erysipeloid dar4 red lesions
, Penicillin or erythromycin
, /accine "or pigs
inoculation
"ingers
, Endocarditis
 0 May occur in those 7ho hae had ale replacements
, :isseminated in"ections may occur but rarely
 
$$
 
(
or in a / shape
 0 Microaerophilic
 0  'onmotile
 
+
agar?colonies may appear
, .ll produce catalase possess mycolic acids
and a uni@ue peptidoglycan&
nasopharnyx or s4in >not considered a
constituent o" normal microbial "lora no
enironmental or animal source?
, C & ulcerans associated 7ith boine mastitis
C & pseudotuberculosis associated 7ith
suppuratie lymphadenitis abscess
 
, Corynebacterium ulcerans in"ection
, Corynebacterium pseudotuberculosis
 
gro7th&
 part . arrests protein synthesis
2(
$tained Corynebacterium cells. The ;*arred; appearance is due to the presence of
polyphosphate inclusions called metachromatic granules. Note also the
characteristic ;!hinese&letter; arrangement of cells.  
C. diphtheriae
diphtheria is al7ays present
liing in cro7ded unsanitary conditions&
, .c@uired ia respiratory droplets "rom carriers
or actiely in"ected indiiduals
 
in"lammation
pseudomem*rane "ormation can cause asphyxiation
4. @iptheroto+in production and toxemia
 0  target organs primarily heart and neres
 
, Stains
Chinese letter arrangement
 0  Produce metachromatic
stain more dar4ly than
remainder o" organism  Corynebacterium
=sed to demonstrate
modi"ied Tinsdale exhibits
halos around the colonies
reactions
 boosters
, Stain purple 7hen gram-stained
, Can be categoried into $ maHor groups  0 Genera o" cocci-shaped organisms- #taphylococcus
#treptococcus and Enterococcus
Gram-Positie Pathogens
, Can be opportunistic pathogens
anaerobes
diision occurs along di""erent planes and the
daughter cells remain attached to one another 
, Salt-tolerant% allo7s them to tolerate the salt
 present on human s4in
enironmental sur"aces >"omites?
staphylococcal diseases in humans
can produce a ariety o" conditions depending on the
site o" in"ection
human s4in that can cause opportunistic in"ections in
immunocompromised patients or 7hen introduced
into the body
Structure and Physiology
, Entry o" only a "e7 hundred bacteria can result
in disease
 0 Production o" enymes
 0 Production o" toxins
 0  #nter"eres 7ith humoral immune responses by
 binding to class G antibodies
 0  #nhibits the complement cascade
$& Clumping Factor >!ound coagulase?
insoluble "ibrin molecules that "orm blood clots
 0  Fibrin clots hide the bacteria "rom phagocytic cells
Structural :e"enses .gainst
capsules?
leu4ocytes
arti"icial sur"aces
to spread bet7een cells
#taphylococcus aureus to "ree itsel" "rom clots
Enymes
+&  β-lactamase
 0  !rea4s do7n penicillin
 0  .llo7s the bacteria to surie treatment 7ith β-
lactam antimicrobial drugs
Enymes >cont&?
"re@uently than #.epidermidis
1& Cytolytic toxins
cells
 0 3eu4ocidin can lyse leu4ocytes speci"ically
$& Ex"oliatie toxins , Causes the patientAs s4in cells to separate "rom each other
and slough o"" the body
Toxins
)& Enterotoxins
and intense omiting associated 7ith staphylococcal
"ood poisoning
Toxins >cont&?
, Food poisoning "rom the ingestion o" enterotoxin-
contaminated "ood
impetigo "olliculitis and "uruncles
 blood and causes shoc4 
o" the heart
aleoli and bronchioles become "illed 7ith "luid
, Dsteomyelitis-in"lammation o" the bone marro7 and
the surrounding bone
arrangements isolated "rom pus blood or other
"luids
, Treatment
staphylococcal in"ections
, #s a semisynthetic "orm o" penicillin and is not inactiated
 by β-lactamase
 
 preenting nosocomial in"ections
 0 .lso important is the proper cleansing o" 7ounds and
surgical openings aseptic use o" catheters or
ind7elling needles an appropriate use o" antiseptics
:iagnosis Treatment and Preention >cont&?
 
, #ndiidual cocci are spherical or ooid arranged in
chains and diploes non-motile some are capsulated
anaerobes "acultatie anaerobes non-spore "ormers&
, Some re@uire +-18< CD$ "or gro7th&
, Streptoccci are alpha hemolytic !eta hemolytic or
nonhemolytic&
1- Group 0 speci"ic cell 7all antigen% Carbohydrate present
in the cell-7all o" many streptococci and "orms the basis o"
serological groupings> 3ance"ield groups .- R-= ?&
$- M protein% MaHor irulence "actor o" group .
Streptococcus pyogenes&
 
Streptolysin D >.SDT? and Streptolysin S>!
hemolysis?
!- #treptococcus agalactiae% These are group streptococci&
C- Groups C and G&
:-  Enterococcus fecalis$E. faecum, E durans?% Group :&
E- #treptococcus bois% 'onenterococcal group : streptococci&
F- #treptococcus anginosis&
G- Group ' Streptococci&
#- #treptococcus pneumoniae&
R- 'utritionally /ariant Streptococci&
3-  Peptostreptococcus >Many Species?&
182
 #athogenesis and !linical 'indings , #n"ections can be diided into seeral categories%
, .- :iseases caused by #. pyogenes"
, )- Puerperal "eer&
, - Streptococcal sore throat
 
$- .cute Glomerulonephritis
, #n espiratory secretions
an thus, i!!erent strain o! S.pyogenes
cause repeat in!ections
To%in secrete #y 
!acterial Pneumonia
Streptococcus pneumoniae '  ()* o! all pneumonia '  +is actors- ol age, season, unerlying
"iral in!ection, ia#etes, alcohol an
narcotic use '  aria#le capsular antigen '  Puri!ie component /capsule0 "accine
1thers that cause pneumonia2
identi"ication
, U-hemolytic5 optochin sensitiity bile
solubility inulin "ermentation
, #ncreased drug resistance
indiiduals%
other high ris4 indiiduals 0 e""ectie + years
 0 ConHugate accine "or children $ to $( months