mixed intestinal fora
presents as acute abdomen
tx is surgical & antibiodics
Key causes of secondary peritonitis
Perforation and localization: appendix, diverticulae, biliary tract, pancreas, surgery
Sites: rlq, llq, or other
Mixed intestinal flora especially anaerobes
Manifestations: fever, chills, night sweats, localized abd. pain (may be mild), symptoms may be masked in seriously ill Pt's.
Organisms that will not grow in the presence of oxygen
______ are normal flora that invade with trama and reduced blood flow (trauma allows infection).
They are usually not transmitted person to person, and infections usually occur and progress slowly.
Name the type of infection based on the following.
Insidious onset of dz
cantiguous to mucosal surfaces
foul smell (about half the time)
severe tissue necrosis
gas in tissue
gram stain appearance of multiple organisms
____ causes 95% of peptic ulcers, most people are exposed to it in childhood, and most importantly has strong urease activity, which help protect it in the gastric envorinment and plays a role in how it invades and causes dz.
It also causes 50-70% of gastric uclers and has a possible association with dyspepsia and gastric carcinoma.
Helicobacter pylori (H pylori)
What is a very common illness (although consequences are minor in US), is the most common cause of death word-wide; and what causes the acute manifestations of this illness?
Diarrhea -- acute diarrhea is caused by infections, medications, ishemia, diverticulitis, graft vs host dz, and toxins.
What type of pathogenic mechanism is associated with n/v, large volume-water diarrhea?
What pathogenic mechanism is associated with tenesmus, fever, pain, bloody small volume diarrhea?
What pathogenic mechanism is assocaited with n/v and abdominal pain soon after ingestion?
Preformed toxin (toxin is formed before food was eaten-- food poisoning)
What are 3 important things to think of when evaluating the severity of diarrhea?
Duration, age, and fecal WBCs
What clues help you determine the likely pathogen?
- Inpatient vs outpatient
- food ingested (hard to accurate)
- incubation period
- Exposure and others affected
Name 5 important culture parameters for stool samples.
- Need loose or watery sample
- Swabs can be used
- Inspects sample: consistency, blood, mucous
- NO microscopic exam
- 1 sample at a time
What are the 3 most common things to look for in a stool culture?
What would you look for in a stool culture with:
a) bloody stool sample
b) like appendicitis
c) recent use of antibiotics
d) recent exposure to shellfish/water
- a) E coli
- b) Yersinia
- c) C difficile
- d) Vibrios
With what pathogens would you
a) perform a toxin assay?
b) What about a antigen assay?
c) What about an acid fast or antigen detection?
a) C diff & E coli
Inhabitants of lower GI
Survive readily in nature
increased colonization of these organisms in hospitalized Pt's
E coli, klebesiella pneumonia, and Proteus mirabilis are most associate with dz.
Over whelming number of serotypes -- outbreaks are due to new serotype in a community.
Normal flora of reptiles, and birds (also found in humans, livestock, mammals and snakes)
Gastroenteritis related to improper food handling (poultry and eggs are a common vector)
highest incidence in children less than 5 and adults older than 70.
Peak incedence in summer and infection requires a high inoculum
S typhimurium and S inoculum are serotypes most associated with dz.
Name the pathogen:
Invasive -- invades mucoas and peyer's patches and then enters blood circulation
Can be found in blood culture (the only cause of diarrhea with this characteristic)
Antacids make one more usceptible to infections
Sx begin 24-48 hrs afer ingestion of contimanated food or water.
n/v, cramping, large volume diarrhea
Resolves spontaneously in 3-4 days
Fever in 50%
Similar to E coli
4 species -- name the most severe
NOT NORMAL FLORA EVER
Transmitted via feces, fingers, food flies
Only 200 organsims can cause dz
High rates of secondary attacks
Mostly a ped. dz in US (day-care centers)
- 4 species are: Shigella dysenteriae (A), S flexneri, S, boydii, and S sonei
- S sonei is the most common in the US (fever, systemic sx, water diarrhea)
Pt comes in with abdominal cramps, tenesmus, fever and bloody, mucoid small volume stools. The pathogen is known to destroy the villi and epithelial cells on the surface of large intestine mucosa -- what is it?
What effect does Bismuth Subsalicylate have on the tongue and stools?
Darkening of toungue and stools (greyish black stools)
On what receptor is loperamide thought to act? Why isn't it associated with sedation, respiratory depression or euphoria?
It acts on opioid receptors. Because it doesn't cross the BBB.