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220 Cards in this Set
- Front
- Back
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What are enteric bacteria?
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Gram-negative bacteria that are associated with gastrointestinal flora or disease.
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What are six families of enteric bacteria?
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1) Enterobacteriaceae
2) Vibrionaceae 3) Pseudomonadeceae 4) Bacteroidaceae 5) Campylobacteraceae 6) Helicobacteraceae |
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What are eight genera that are part of the Enterobacteriaceae family?
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1)Escherichia
2) Salmonella 3) Shigella 4) Klebsiella 5) Proteus 6) Enterobacter 7) Serratia 8) Yersinia |
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What are the oxygen requirements of most G- rods?
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Facultative anaerobes
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What are three exceptions of G- rods that are NOT facultative anaerobes?
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Pseudomonas and Bacteroides are obligate anaerobes
Campylobacter is microaerophilic |
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What are three common metabolic characteristics of most G- rods?
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1) Ferment glucose to produce acid and gas
2) Reduce nitrates to nitrites 3) Oxidase negative |
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What is the one exception to the three common metabolic characteristics of most G- rods?
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Pseudomonas does not ferment glucose and is oxidase positive.
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What biochemical properties can be used to differentiate enteric bacteria?
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1) Ability to ferment lactose
2) Ability to produce urease 3) Ability to produce hydrogen sulfide (H2S) |
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Which three intestinal pathogens cannot ferment lactose?
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1) Shigella
2) Salmonella 3) Pseudomonas |
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Which three intestinal pathogens can ferment lactose?
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1) Escherichia
2) Enterobacter 3) Klebsiella EEK! a mouse eats cheese (lactose) |
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Which five enteric bacteria produce urease?
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1) Helicobacter
2) Klebsiella 3) Proteus 4) Providencia 5) Morganella |
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What is the function of urease?
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Metabolizes urea to form carbon dioxide ammonia, and water, producing a habitable alkaline environment.
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What differential media can be used to isolate enteric bacteria from G+ bacteria?
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Eosin-methylene blue (EMB) agar
MacConkey agar, Hektoen enteric agar |
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What characteristic do Eosin-methylene blue (EMB) agar, MacConkey agar, &Hektoen enteric agar select for?
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G- bacteria
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How does EMB inhibit growth of G+ bacteria?
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Aniline dyes
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How does MacConkey agar inhibit growth of G+ bacteria?
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Bile salts and crystal violet
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How does Hektoen enteric agar inhibit growth of G+ bacteria
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Bile salts
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What characteristic do Eosin-methylene blue (EMB) agar, MacConkey agar, &Hektoen enteric agar screen for?
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Lactose-fermenting versus
Lactose-NONfermenting bacteria |
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How do lactose-fermenting bacteria appear on EMB?
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Metallic-green colonies
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How do lactose-fermenting bacteria appear on MacConkey agar?
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Pink colonies
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How do lactose-fermenting bacteria appear on Hektoen enteric agar?
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Yellow or orange
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How do nonlactose-fermentig bacteria appear on EMB?
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Translucent
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How do nonlactose-fermenting bacteria appear on macConkey agar?
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Translucent
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How do nonlactose-fermenting bacteria appear on Hektoen enteric agar?
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Blue-green
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What other media selects against G+ organisms?
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Salmonella-Shigella agar
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Which four surface antigens are used to differentiate among enteric bacteria?
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O antigen
H antigen K antigen and pili |
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What is the O antigen?
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Heat-stable cell wall antigen located on the most external surface of LPS (remember "O" for outer)
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What part of the O antigen confers unique characteristics to different O antigens?
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Sugars, e.g., the O157 subtype, which is differentiated by its sugar moiety.
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What is the H antigen?
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Antigen located on teh flagella
Only those bacteria with "flagHella" will have an H antigen. |
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What is the K antigen?
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Antigen associated with the capsule of fimbriae
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What are pili?
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Antigenic fimbriae responsible for attachment and colonization of an organism.
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What three characteristics make enteric bacteria pathogenic?
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1) Enterotixins
2) Endotoxins 3) Capsule |
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How are enterotoxins pathogenic?
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They cause transduction of fluid into the ileum.
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How are endotoxins different from enterotoxins?
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Enterotoxins are released from bacteria.
Endotoxins are found in the LPS complex of the bacterial outer membrane. |
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What endotoxin do almost all G- rods contain?
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LPS
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What is a common component in most endotoxins?
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Toxid Lipid A
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Why are endotoxins pathogenic?
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1) Stimulate release of tumor necrosis factor, interleukin-1, and IL-6 leading to hypotension.
2) Stimulate release of IL-1 and IL-6 leading to fever. 3) Hemorrhage in the intestine, adrenal glands, heart, and kidneys. |
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How is the capsule pathogenic?
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It suppreses phagocytosis
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Where do G- rods usually cause disease?
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Intraintestinal, extraintestinal, or both, depending on genera.
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Which G- rods cause disease primarily inside the enteric tract?
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Shigella
Vibrio Helicobacter |
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Which G- rods cause disease outside of the enteric tract?
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Klebsiella, Enterobacter, Serratia, Proteus, Providencia, Morganella, Pseudomonas, and Bacteroides
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Which G- rods cause disease both inside and outside of the enteric tract?
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Escherichia
Salmonella Yersinia Campylobacter |
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What is E. coli?
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Lactose-fermenting
Oxidase-negative G- Enteric rod |
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Where is E. coli found?
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Part of the normal flora of the human gut.
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What are three metabolic characteristics of E. coli?
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1) Facultative anaerobes
2) Ferment glucose and lactose 3) Reduce nitrates to nitrites. |
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How is E. coli transmitted?
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Fecal-oral and food-borne transmission.
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What enables E. coli to adhere to the epithelium of the GI tract?
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Pili or fimbriae
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How are E. coli strains typed?
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O antigen
H antigen K antigen |
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What is teh most common clinical manifestation of E. coli infection?
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Diarrhea
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What extraintestinal diseases does E. coli commonly cause?
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1) UTI
2) Cystitis 3) Pyelonephritis 4) Sepsis 5) Neonatal meningitis 6) hemolytic uremic syndrome 7) Endotoxic shock 8) Pneumonia |
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How is E. coli infection diagnosed?
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Culture
biochemical tests serological tests |
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Which antibiotics are commonly used to treat E. coli?
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Ampicillin
Cefotaxime ciprofloxacin Trimethoprim-sulfamethoxazole (Bactrim) |
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What are five common pathogenic species of E. coli?
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1) Enterotoxigenic E. coli (ETEC)
2) Enteropathogenic E. coli (EPEC) 3) Enterohemorrhagic E. coli (EHEC) 4) Enteroinvasive E. coli (EIEC) 5) Enteroadherent E. coli (EAEC) |
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Which strains cause bloody diarrhea?
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EHEC
EIEC |
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What does ETEC commonly cause?
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Traveler's diarrhea
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What are two enterotoxins released by ETEC?
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1) Heat-labile toxin (LT)
2) Heat-stable toxin (ST) |
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How many subunits does heat-labile toxin have?
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2 subunits
A & B |
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What is the pathogenesis of heat-labile toxin?
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1) Subunit A: activates adenylate cyclase, increases cyclic adenosine monophosphate, increases secretion of water adn chloride ions, and inhibits sodium reabsorption leading to elecrolyte imbalance, hypermotility, and diarrhea (similar to cholera toxin)
2) Subunit B: binds Gm1 ganglioside at the brush border of the small intestine, facilitating entry of Subunit A 3) Heat-Labile toxin is essentially the same as the cholera toxin produced by Vibrio cholerae. |
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What is the pahtogenesis of heat-stable toxin?
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Activates guanylate cyclase in epithelial cells of the small intestine, increasing cyclic guanosine monophosphate and causing fluid seretion.
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How does ETEC cause disease?
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Attaches to the small intestinal epithelium via pili and produces enterotoxins that cause hypersecretion of chloride ions and block absorption of sodium, resulting in massive amounts of water in the lumen of the gut
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What does EPEC commonly cause?
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Watery diarrhea in infants.
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When does EPEC infection usually take place?
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During parturition (birth) or in utero.
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How does EPEC caues disease?
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Bacteria in the gastrointestinal tract attach to mucosal cells in the small intestine and destroy microvilli with attaching and effacing lesions, also resulting in an inflammatory response.
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What is the primary reservoir for EHEC?
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Cattle
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How does cattle as a reservoir relate to outbreaks of EHEC?
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Eating undercooked beef.
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What does EHEC commonl cause?
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Hemorrhagic colitis and bloody diarrhea?
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How does EHEC cause disease?
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Attaches to and detroys mucosal cells with attaching and effacing lesions and also produces verotoxin, a Shiga-like toxin that enters the bloodstream causing endothelial damage and platelet aggregation, resulting in throbus formation.
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Does EHEC invade the bloodstream?
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NO
Only the shiga-like toxin and LPS enter the blood. |
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What life-threatening condition is associated with EHEC?
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Hemolytic uremic syndrome (HUS)
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What strain of EHEC has resulted in recent outbreaks and hemolytic uremic syndrome?
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E. coli O157:H7
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What sugar is not fermented by this strain that is fermented by other strains of E. coli?
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Sorbitol
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What disease does EIEC cause?
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Dysentery (bloody diarrhea and fever) similar to shigellosis.
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What disease does EAEC cause?
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Traveler's diarrhea and persistent diarrhea in children.
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What is Salmonella?
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Nonlactose-fermenting, oxidase-negative, G- rods with flagella located over the entire surface of the bacteria.
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How many different species of Salmonella exist?
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One,
S. enterica |
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How many different serotypes of S. entrica exist?
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More than 1500
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Which serotype is an exclusively human pathogen?
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S. typhi
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Where are the other serotypes found?
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Animals (reptiles, birds, mammals, pet turtles) and foods (eggs and poultry).
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How is salmonella transmitted?
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Ingestion of bacteria, usually from food.
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What natural host defense inhibits Salmonella infection?
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Stomach acid
Decreased stomach acid increases the risk of Salmonella infection. |
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What populations are particularly susceptible to Salmonella infection?
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1) Elderly
2) Young Children 3) Patients who have had a gastrectomy 4) Those who chronically take antacids |
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What hematological disease classically predisposes children to Salmonella infection, including osteomyelitis?
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Sickle cell anemia
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Where is S. typhi usually found in chronically infected individuals?
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Gall bladder
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Where are most other strains of Salmonella usually found in chronically infected individuals?
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Bone Marrow
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What are two metabolic characteristics of Salmonella?
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1) Produces acid adn gas during the fermentation of glucose
2) Produces hydrogen sulfide from sulfur-containing compounds. |
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What are three virulence factors of Salmonella?
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1) LPS
2) Vi capsular antigen (found in S. typhi) 3) RCK (resists complement killing) |
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What is the capsular antigen of Salmonella similar to?
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K antigen of E. coli
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What are the different diseases caused by Salmonella?
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1) Gastroenteritis (S. enteritidis and S. typhimurium)
2) Enteric and typhoid fever (S. typhi) 3) Sustained bacteremia, which occurs when the bacteria seed atherosclerotic plaques. |
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What are the symptoms of gastroenteritis caused by Salmonella?
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Nausea, vomiting, nonbloody diarrhea, fever, adn cramping caused by S. enteritidis serotype with 48 hours of consumption of contaminated food or water.
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How long do these symptoms of gastroenteritis caused by Salmonella last?
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Usually resolve within 72 hours
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What is the treatment for gastroenteritis caused by Salmonella?
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No antibiotic treatment is needed, only symptomatic treatment with rehydration
Antibiotics may actually prolong the course of the disease. |
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How does S. typhi cause enteric fever?
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1) Bacteria enters the gastrointestinal system.
2) Bacteria invade small intestinal epithelial cells. 3) Bacteria pass to the submucosa 4) Phagocytosed by macrophages 5) Survive in the macrophages and are transported to the reticular endothelial system 6) Salmonella can then re-enter the gut via the liver and bile. |
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What are the symptoms of enteric fever?
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Life-threatening systemic illness with fever, abdominal pain, and a truncal maculopapular rash caused by S. typhi serotype.
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What is the incubation period for salmonella enteric fever?
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1-3 weeks
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What are the complications of enteric fever?
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Intestinal hemorrhage,
focal infections, and endocarditis |
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What agar is used to isolate Salmonella?
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MacConkey agar
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What is teh treatment for Salmonella?
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1) Enterocolitis: resolves without treatment; antibiotics may prolong excretion
2) Enteric fever: using either ceftriaxone or ciprofloxacin substantially decreases mortality from 15% to 1% |
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Is there a vaccine available for Salmonella?
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YES
But, only for S. typhi serotype, which offers 50% to 80% protection. |
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What is Shigella?
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Nonmotilie, nonlactose-fermenting, oxidase-negative, G- enteric rods.
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What is teh reservoir for Shigella?
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Humans only, there is no other animal reservoir
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How is Shigella transmitted?
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Fecal-oral and food-borne transmission
Four F's: fingers, flies, food, feces |
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What does it mean Shigella need a low dose to be infectious?
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Even a low number of organisms can cause disease if ingested (-200)
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Is the infectious dose low or high for Shigella?
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Very Low
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How many different serotypes of Shigella exist?
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40 serotypes are organized into 4 species based on the polysaccharide O antigen.
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What Shigella serogroup is the most common in the US?
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S. sonnei
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What toxin is associated with Shigella?
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Shiga toxin, which is only produced by S. dysenteriae serotype 1.
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What is shiga toxin?
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An exotoxin with cytotoxic properties
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How does Shigella cause disease?
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Invades and destroys the mucosa of the large intestine, but does not cause bacteremia.
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What disease does Shigella commonly cause?
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Dysentery
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What are the symptoms of this disease?
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Blood diarrhea, mucus, and painful abdominal cramping; seizures in children.
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How long do symptoms of dysentery last?
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Untreated dysentery resolves in 1 week.
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What selective agar can be used to identify Shigella?
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Hektoen agar
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What is Hektoen agar?
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Agar that can differentiate on the basis of lactose fermentation and hydrogen sulfide production and which contains bromthymol blue pH indicator and bile salts for inhibition of G+ organisms.
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What is the treatment for Shigella dysentery?
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Ciprofloxacin or azithromycin can reduce th duration of the illness, but concerns about resistance and increased frequency of hemolytic uremic syndrome have made treatment controversial.
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What is Campylobacter?
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Curved, comma, or S-shaped organisms with a single polar flagellum.
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What are the oxyen requirements for Campylobacter?
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Microaerophilic (they require 5% oxygen, not atmospheric oxygen of 21%).
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What are the reservoirs of Campylobacter?
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Mammals and birds
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How is Campylobacter transmitted to humans?
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1) Fecal-oral transmission
2) Direct contact (especially poultry) 3) Contaminated water |
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Who is typically susceptible to Campylobacter infection?
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Children
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What species of Campylobacter is a major human pathogen?
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C. jejuni
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What is the pathogenesis of C. jejuni?
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1) Following oral ingestion, C. jejuni colonizes intestinal mucosa and invades intestinal epithelium, with resultant ulceration and bleeding of mucosal surface.
2) Rarely, C. jejuni may enter the blood-stream, disseminating to multiple organs, particularly in the immunocompromised. |
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What diseases does C. jejuni cause?
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Acute enteritis, traveler's diarrhea, pseudoappendicitis, and bacteremia.
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What is the incubation period for acute enteritis caused by C. jejuni?
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1-7 days
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What are three complications of C. jejuni infection?
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1) Guillain-Barre syndrome
2) Septic abortion 3) Reactive arthritis |
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How is Campylobacter infection diagnosed?
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Growth on selective media in microaerophilic conditions.
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Which strain of Campylobacter causes vascular and central nervous system infection?
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C. fetus
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What is the treatment for C. fetus?
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1) Symptomatic treatment with fluid and electroyte replacement.
2) Treat with ampicillin or third-generation cephalosporin for persistent symptoms or bloody diarrhea. |
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What is Vibrio?
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Rapidly motile short, curved oxidase-positive, G- rods with a single polar flagellum.
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What are the oxygen requirements of Vibrio?
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Facultative anaerobes
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What are the natural hosts of Vibrio?
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Marine shellfish and plankton.
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How are the different Vibrio strains classified?
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Based on their O antigens.
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Which strains of Vibrio are pathogenic?
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1) V. cholerae O1 strains
2) V. cholerae non-O1 strains 3) V. parahaemolyticus 4) V. vulnificus |
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How is V. parahaemolyticus infection differentiated from V. cholera infection?
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V. parahaemolyticus grows in 8% NaCl solution, but V. cholera does not.
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How are the biotypes of V. cholerae O1 differentiated?
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By differences in biochemical reactions.
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What are the two biotypes of V. cholerae O1?
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El Tor and Classic
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How do El Tor and Classic V. cholerae differ?
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El Tor produces hemolysins, has higher carriage rates, and can survive in water longer.
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How are V. cholerae transmitted?
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By contaminated food and water.
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How do V. cholerae cause disease?
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After ingestion, bacteria attach to the small intestine, but do not invade the mucosa, where they produce cholera toxin.
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How does cholera toxin cause disease?
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Causes outpouring of water and chloride ions into the lumen of the intestine.
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How many subunits does cholera toxin have?
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2
A (active) and B (binding) |
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What is the function of the A subunit of cholera toxin?
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A1 adenosine diphosphate ribosylates Gs protein, activating adenylate cyclase, which increases cAMP yielding increases chloride ion and water flow to the lumen
A2 facilitates penetration of cell membranes |
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What is the functoin of the B subunit of cholera toxin?
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Binds to Gm1 ganglioside receptor of epithelial cells.
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How is the diarrhea classically characterized in cholera?
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"Rice water" stools
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What is the cause of death from cholera?
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Severe dehydration
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What condition predisposes individuals to infection with Vibrio?
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Reduced stomach acid, e.g., from gastrectomy or antacid use.
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How is V. cholerae identified?
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Growth on standard media such as blood and MacConkey agars
Thiosulfate-citrate-bile salts-sucrose (TCBS) enhances isolation. |
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What food is associated with V. parahaemolyticus infection?
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Inadequately cooked seafood.
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What is the treatment for cholera?
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Replacement of fluids and electrolytes can reduce death rates form 50% to less than 1%
Tetracycline can shorten symptoms |
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What food is associated with V. parahaemolyticus infections?
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Watery diarrhea, nausea, vomiting, abdominal cramps, and fever.
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What is the treatment for V. parahaemolyticus?
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Symptomatic treatment only because antibiotics do not alter the course of infection.
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What are the clinical manifestations of V. vulnificus infection?
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1) Soft-tissue infections (cellulitis)
2) Septicemia in the immunocompromised and in those with chronic liver disease. |
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What is Yersinia?
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Small, encapsulated, G- rods
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What three species of Yersinia cause disease in humans?
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1) Y. enterocolitica
2) Y. pseudotuberculosis 3) Y. pestis |
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What species causes disease of the gastrointestinal tract?
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Y. enterocolitica
Y. pseudotuberculosis |
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What disease does Y. pestis causes?
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Bubonic and pneumonic plague
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What are the characteristics of Y. enterocolitica and Yersinia pseudotuberculosis?
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1) They can grow at 4C, 27C, or 37C
2) motile at 25C but not at 37C 3) Lactose negative |
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How are Y. enterocolitica and Yersinia pseudotuberculosis transmitted?
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Ingestion of contaminated foods
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Which virulence factors are associated with Yersinia?
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V and W antigens
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How do Y. enterocolitica and Yersinia pseudotuberculosis cause disease?
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They cause ulcerative lesions in terminal ileum and necrosis in Peyer patches with enlargement of mesenteric lymph nodes.
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What disease is caused by Y. enterocolitica and Yersinia pseudotuberculosis?
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Entercolitis
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What are teh symptoms of entercolitis caused by Y. enterocolitica and Yersinia pseudotuberculosis?
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Fever
Abdominal pain Diarrhea, which may mimic appendicitis. |
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What are two complications of Yersinia infection?
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1) Reactive polyarthritis
2) Erythema nodosum |
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How is Yersinia infection diagnosed?
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Growth on macConkey or cefsulodin-irgasan-novobiocin (CIN) agar
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What is the treatment for Y. enterocolitica and Yersinia pseudotuberculosis infection?
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1) Antibiotics are of questionable value if infection is limited to the gastrointestinal tract
2) Ciprofloxacin or trimethoprim-sulfamethoxazole for systemic infection. |
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What is Helicobacter?
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Curved or spiral organisms with multiple polar flagella.
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What are the oxygen requirements of H. pylori?
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Microaerophilic
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What enzyme does Helicobacter produce?
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Urease
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What is the function of urease?
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Metabolizes urea to form carbon dioxide, ammonia, and water, producing a local habitable alkaline environment in the normally acidic stomach.
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What is unusual about where some Helicobacter colonize humans?
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They can only colonize the stomach, whre most bacteria cannot.
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Where does Helicobacter live in the stomach?
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In the mucus layer adjacent to the mucosa.
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How is Helicobacter transmitted?
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Person to person
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How long will a person be infected with Hlicobacter?
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If not treated, teh infection can be life-long.
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How does Helicobacter cause disease?
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Does not invade the epithelium, but causes chronic inflammation of the mucosa by releasing cytotoxins; the ammonia may also cause injury and potentiate the effects of the cytotoxin.
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What characterizes initial and chronic Helicobacter infection?
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Initial infection is characterized by acute gastritis, occasionally with diarrhea.
Chronic infection is characterized by gastritis (usually asymptomatic) and can lead to gastric and duodenal ulcers, gastric carcinoma and gastric B-cell lymphoma. |
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Are most Helicobacter infections symptomatic?
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No, most are asymptomatic.
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What noninvasive tests can diagnose Helicobacter infection?
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Enzyme-linked immunoabsorbent assay (ELISA) for serum antibodies to H. pylori; breath test for urease.
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What invasive test can be used to diagnose Helicobacter infection?
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Biopsy via endoscopy
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What is the treatment of H. pylori?
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Combination therapy, such as metronidazole, tetracycline, and bismuth or metronidazole, clarithromycin, and a proton pump inhibitor.
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What is Enterobacter?
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Lactose-fermenting
motile G- rods |
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Who is usually susceptible to Enterobacter infection?
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Hospitalized patients, in association with antibiotic treatment, catheters, or invasive procedures.
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What are the clinical manifestations of Enterobacter infection?
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Pneumonia
UTI |
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What is Klebsiella?
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Lactose-fermenting
nonmotile G- rods |
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What is the distinguishing characteristic of Klebsiella?
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Has a large capsule, giving colonies a mucoid appearance.
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What infections can Klebsiella cause?
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Necrotizing lobar pneumonia
UTIs Bacteremia |
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Which individuals are most susceptible to Klebsiella pneumonia?
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Alcoholics
Diebetics Pts with COPD |
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What does the sputum of a patient with Klebsiella pneumonia look like?
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Currant-jelly appearance
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What is Serratia?
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Motile
Slow lactose-fermenting G- rods |
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What species of Serratia most commonly infects humans?
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S. marcescens
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What disease does Serratia most commonly cause?
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Pneumonia and UTI mainly in the immunocompromised.
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How does Serratia appear in culture?
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Some strains produce a red pigment
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What is a common clinical manifestation of Proteus infection?
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UTI
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What additional complications are seen with Proteus infection in the immunocompromised?
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Pneumonia
Wound infection Septicemia |
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What enzyme do Proteus species produce?
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Urease
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What is a significant complication of Proteus infection and increased urine pH?
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Struvite stone formation containing magnesium, ammonium hydroxide, and phosphate.
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How does Proteus appear on agar plates?
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Swarming bacteria
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What is Bacteroides?
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Slender
G- rods or coccobacillus |
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What are the oxygen requirements of Bacteroides?
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Obligate anaerobes
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Where is Bacteroides normally found?
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it is the predominant organism of the human colon.
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Which Bacteroides species is a major human pathogen?
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B. fragilis
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What is the main virulence factor of B. fragilis?
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Polysaccharide capsule
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Why is the polysaccharide capsule the main virulence factor of B. fragilis?
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It conveys resistance to phagocytosis adn can trigger abscess formation
The capsule contains little or no endotoxin. |
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How does B. fragilis infection occur?
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A break in the mucosal surface allows bacteria to enter the blood stream.
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What are three infections that B. fragilis causes?
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1) Sepsis
2) Peritonitis 3) Abscess formation These infections usuallly occur below the diaphragm |
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How does the presence of facultative anaerobes contribute to the pathogenesis of B. fragilis?
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Facultative anaerobes utilize oxygen, thereby producing an environment with a reduced oxygen concentratoin which allows B. fragilis to grow.
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How are B. fragilis infections diagnosed?
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Culture of infected site
Gas chromatography Biochemical tests |
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How is B. fragilis cultured?
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Growth in anaerobic conditions on blood agar plates containing kanamycin and vancomycin to inhibit growth of unwanted orgainsms.
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What does gas chromatography detect?
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Short-chain fatty acids that are produced by B. fragilis.
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What is the treatment for B. fragilis infection?
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Metronidazole
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What is Prevotella?
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Slender
G- rods |
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What are the oxygen requirements of Prevotella?
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Obligate anaerobes
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Where is Prevotella normally found?
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Normal flora of the mouth and upper GI and respiratory tracts.
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Which species of Prevotella is the most common human pathogen?
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P. melaninogencia
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How does P. melaninogencia infection occur?
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A breat in the mucosal surface allows bacteria to enter teh bloodstream
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What are two infections that P. melaninogencia causes?
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1) Sepsis
2) Abscess formation These infections usually occur above the diaphragm |
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How are P. melaninogencia infections diagnosed?
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1) Culture of infected site
2) Gas chromatography 3) Biochemical tests |
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How does P. melaninogencia appera on blood agar?
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Black colonies
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What is the tretment for P. melaninogencia?
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Metronidazole
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What is Porphyromonas?
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Anaerobic
G- rods |
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What are two species of Porphyromonas that can caue disease in humans?
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P. gingivalis
P. endodontalis |
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What diseased can P. gingivalis and P. endodontalis cause?
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Peridontal disease, including gingivitis and dental abscess.
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