Gram + Rods Flashcards
What are important Gram positive Rods?
1- spore-forming include: A- aerobic → bacilli B- anaerobic → clostridial 2. Non-spore forming include A - filamentous → actinomycetes and nocardia B- non-filamentous → corynebacteria
Explain corynebacterinen diphtheriae? Other name?
What are it’s characteristics?
Where do they collect energy?
They are G + Rod shop (club shaped)
Kleb’s -loeffler bacillus
Non motile, non capsulated, non sporting, pile present
Met -achromatic granules are store house of Bacteria
Cell wall of cortnebactormn is lipid rich and contain which types off acid?
Lipid cell wall rich in mesodia minopimelic acid, arabinogtactam polymers, and short chain mycolic acid.
If they stained by Albert’s stair hour do they appear?
They appear green with bluish black metachromatic granules at the poles.
Where do corynebacterium habitate?
1 -nasopharynx, skin lesions
2- mouth, throat, nose, skin
3- patient carry Bacteria upto 3 mounts after infection.
What are subtype of corgnebacturinn diphtheriae?
And how to distinguish between them biochemically, and by culturing
Biochemically:-
Gravis strain can ferment starch and sugar.
Interceding and mitis can’t.
Laboratory
1- Mites:- typically arranged on loeflour media and circular glistening (shining) black on Tellurrite media.
2- inter-medium;- irregular, No metachromatic granules on loeffler media and she all, smooth, grey-black, with pole prephral on telluride media.
3-Gravis:- club shap, few metachromatic granules on loeffler media and flat gray, irregular edges on telluride media.
Pseudomonbrane formed by C. Diphtheria is composed of what?
Fibrin, bacteria and inflammations cells
C. Diphtheria toxin ‘s treated with what?
FormaldeHyde
What are symptoms of diphtheria?
1- pheaerynagitis
2 -fever
3- swelling of neck
Toxin produced by c.diphtherra causes which disorders * peripheral organ?
1-paralysis 2- congestive heart failure 3-Nasopharyngeal dipherica causes A- sore throat B- dysphagia C- Bloody, nasal discharge D- pseudomembrane formation
Define bacillus anthraces?
They has tendency to form long chain of Rods . characterized by rough, uneven surface.
What is nature of a. antheracis capsule?
Glutamic acid polypeptide capsule. Has antiphagocytic properties
What are exotoxins produced by bacillus anthracis?
Lethal factor, edema factor, and protective antigen
In which stage do B. anthraces multiply?
In vegetative state
T /F cutanous anthrax usually begins 2-5 days. After inoculation of spores into exposed part of body.
True
What is initial lesion of skin anthrax? And progress to what?
Erythematous papule, progress after 7-10 days into black Escher, surrounded by edema. May progress to massive local edama, toxemia and bacteremia.
Explain pulmonary anthrax?
Is contracted by inhalation of spores, they called woolsorter’s disease., in pulmonary syndrome,1-5 days of mild Fever aus non productive coach lead to progressive respiratory distress and cycrosis, spread to Bloodstream and CNS follow rapidly.
Treatment of chaise. Of anthrax?
What are other alternative of treatment?
Penicillin
Doxycycline or ciprofloxacin are alternatives
Which vaccine is used for an anthrax?
Pasteur’s vaccine
What’s function of anthracis capsule
capsule aid in survival, eventually allowing production of large enough amounts of the exotoxins to causedisease.
- Where do bacillus cereus found?
_ T/F bacillus cereus is not opportunistic pathogens to immunocompromised patients
-T/F it is considered as normal flora
-T,/F It is able to grow either in the presence or in the absence of oxygen.
T/F Bacillus cereus are not easily killed by alcohol
found in mashed potatoes, beef stew, apples, hot chocolates False False True True
When does B. cereus regarded as pofhogenie?
a concentration of 10 5 bacteria or more per gram of food is considered diagnostic.
Explain morphology of B. cereus?
Gram +, Rod shap, squad end, short chains
Clear cut junction between chains can be seen,, It is motile and flagellated, motile by two types of motility, swimming and swarming.
On which culture do b-cereus grow? Tempwatre? Color?
on nutrient agar or peptone media. varies from 20°C to 40°C, mostly 37°C. grey-white color.
T,/ F On blood agar, B-cereus is beta-hemolytic.
T
What is benefit of baccarat media?
promotes the growth and identification of B. cereus but inhibits the growth of background flora. Bacillus cereus colonies turn pink-orange with an opaque halo.
T,/F B. cereus is most commonly associated with food poisoning, specially rice.
T
B. Cereus is mediated by two enterotoxins what are they?
.The heat-stable, proteolysis-resistant enterotoxin causes the emetic form of the disease. emetic form is manifested by nausea, vomiting, abdominal cramps
.The heat-labile enterotoxin causes the diarrheal form of the disease; each stimulates the adenylate cyclase–cyclic adenosine monophosphate system in intestinal epithelial cells, leading to profuse watery diarrhea.
When B. cereus become opportunistic infector?
posttraumatic eye infections, endocarditis, and bacteremia.
What are toxins produced by B. Cereus?
1 necrotic toxin (a heat-labile enterotoxin),
2 cereolysin,
3 phospholipase C (a potent lecithinase).
What are two for of Food poisoning of B. Cereus?
vomiting disease (emetic form) and diarrheal disease (diarrheal form).
Explain emetic form poisoning of B. Cereus?
emetic form of the disease results from the consumption of contaminated rice.
The emetic form of the disease is an intoxication, caused by the ingestion of the enterotoxin and not the bacteria.
How can B, cereus affect eye infection?
B. cereus ocular infections usually occur after traumatic, penetrating injuries of the eye with a soil contaminated object.
What’s cause of diarrheal form infection caused by B. Cerens?
enterotoxin is responsible for the profuse watery diarrhea, nausea, and abdominal cramps.
How to treat B. cereus?
food poisoning require only supportive treatment.
During vomiting only rehydration is requires.
invasive disease require antibiotic therapy. Bacillus cereus is susceptible to clindamycin, erythromycin, vancomycin, aminoglycosides, and tetracycline. It is resistant to penicillin and trimethoprim..
What is peptostreptococeus?
anaerobic Gram-positive cocci
They causes. oropharyngeal infections and brain abscess. Mostly found in month and intestine
Give an example about Gram negative anaerobes cocci?
veilonella, lives in intestine,
What ‘s bacteroids fragile?
Gram negative bacilli, has polysaccharide capsule, produce enterotoxins lives in lintestue and cause abdominal abscess.
T/ F propionibacterium are among the most common bacteria in the normal flora of the skin.
True
Where do eubacterium mostly found?
They are grave positive bacilli mostly found on colonic Flora.
When do anaerobic Bacteria causes pallogenesity?
displaced from normal flora to deeper sites
When do Brain abscess fore’s
Brain abscess typically involves anaerobic bacteria.
What are serious infections caused by anaerobic Bacteria’s?
1- abscesses within the cranium, thorax, peritoneum, liver, and female genital tract
2- chronic sinusitis, chronic otitis media, osteomyelitis,
3-necrotizing fasciitis) and thrombophlebitis are common complications.
4-A foul-smelling pus
Which anaerobic Bacteria is resistant to beta-lactam?
Bacteriodes fragilis
Best treatment to anaerobic bacteria?
Co-existense condition, penicillin and other beta-lactams are used in combination with clindamycin
