GI #10 Flashcards
Clostridioides difficile is a spore-forming, _____, _______
Toxin-producing, Gram-positive anaerobic bacteria
Risk factors for C-diff
- Recent ABX use (Clindamycin)
- Advanced age
- Gastric suppression therapy (PPI, H2 blockers)
- Amoxicillin in children
- Chemotherapy also
Symptoms of C-diff
- Watery, non-bloody diarrhea
- Abdominal cramps, fever, abdominal tenderness
- Complications: Toxic megacolon, bowel perforation
What is the initial test of choice for C-diff
-C. diff toxin (stool)
Other tests for C-diff
- Leukocytosis and increased WBC classic (high WBC count)
- Sigmoidoscopy in select patients: pseudomembranes
Treatment for C-diff
- Discontinue offending agent/ABX
- Contact precautions and hand hygiene (spores cannot be killed with alcohol)
- Oral Vancomycin and Oral Fidaxomicin are first line agents
- -Metronidazole is alternative
If the patient has frequently recurrent C-diff, what treatment should be done?
-Fecal microbiota transplant
What medication class should you NOT give with invasive diarrhea?
-Anti-motility drugs (may cause toxicity)
Yersinia Enterocolitica is shaped
-Gram negative coccobaillus with bipolar staining (safety pin appearance)
Yersinia Enterocolitica comes from
Contaminated pork (MC in the US -Milk, water, and tofu
Symptoms of Yersinia Enterocolitica
- Fever
- Abdominal pain (can mimic acute appendicitis)
- Mesenteric lymphadenitis
How do you diagnose Yersinia Enterocolitica?
-Cultures from stool, pharynx, or mesenteric nodes
Treatment for Yersinia Enterocolitica
- Fluid and electrolyte replacement
- Severe: Fluoroquinolones, Bactrim
MCC of bacterial enteritis in the US
Campylobacter Jejuni
Campylobacter Jejuni is the MC antecedent event in
Post-infectious Guillan-Barre Syndrome
Sources of campylobacter jejuni enteritis
- Contaminated food: raw or undercooked poultry
- Raw milk, water, dairy cattle
- Puppies in children!
Symptoms of campylobacter jejuni
- Fever, crampy abdominal pain
- Diarrhea (watery then bloody)
On stool culture, what is shown for campylobacter jejuni?
Gram-negative, S (comma or seagull shaped) organisms
Treatment for campylobacter jejuni
Fluid and electrolyte replacement is mainstay
Macrolides (Azithromycin) is first choice for those patients who need it
How do you get infected with Enterohemorrhagic E Coli 0157:H7
Ingestion of undercooked ground beef, unpasteurized milk or apple cider, day care centers, contaminated water
What is the pathophysiology of Enterohemorrhagic E. Coli
-Shiga toxin causes endothelial damage leading to hemorrhage
MC in children and elderly
Symptoms of enterohemorrhagic E. Coli
- Watery then bloody diarrhea
- Abdominal cramps, fever
With enterohemorrhagic E. Coli, why should you avoid ABX in children?
-Due to increased incidence of Hemolytic uremic syndrome (increased release of Shiga Toxins)
What bacteria is Typhoid Fever MC by?
-Salmonella typhi
How do you get Typhoid Fever?
-Travel to areas where sanitation is poor (South-Central Asia) or contact with carrier
Symptoms of Typhoid Fever
- Headache, Fever, Chills, Abdominal Pain
- Constipation, then diarrhea (Pea-Soup Green in color)
- Malaise
- Anorexia
On physical exam, what are some findings in Typhoid Fever?
- Fever with bradycardia
- Rose spots (macular rash that spreads from trunk to extremities) in second week
- Hepatosplenomegaly
- Delirium, dehydration in later stages
Treatment for Typhoid Fever
- Oral rehydration and electrolyte replacement
- ABX: Fluoroquinolones are first line (Ciprofloxacin, Ofloxacin)
Nontyphoidal Salmonella is one of the MC cause of food borne disease in the US. What is this from?
-Poultry, eggs, milk products, fresh produce and contact with reptiles (turtles)
Symptoms of nontyphoidal salmonella
- Fever, nausea, vomiting, cramps, diarrhea (pea soup in color) may be bloody
- Headaches
- Malaise
What is the first line medication class used for Nontyphoidal salmonella?
Fluoroquinolones (Cipro and Ofloxacin)
What bacteria causes Shigellosis MC in the US?
Shigella Sonnei
However, what species of Shigella produces the most toxin?
Dysenteriae
Shigellosis is caused by a highly virulent gram negative rod. What is the transmission of this bacteria?
Fecal-oral contamination
Symptoms of Shigellosis
- Lower abdominal pain
- Explosive watery diarrhea that progresses to mucoid and bloody diarrhea
- Febrile seizures (especially in kids)
What are some complications of Shigellosis?
- Reactive arthritis (Reiter Syndrome)
- HUS (in kids)
- Toxic megacolon
What is shown on a CBC for Shigellosis?
-Leukemoid reaction (WBC > 50,000)
Although oral and electrolyte repletion and hydration is mainstay, what class of medication is used for treatment of Shigellosis if severe?
Fluoroquinolones (Cipro and Ofloxacin)
-Other options: Bactrim, Azithromycin
Source of Giardia Lamblia
-Contaminated water from remote streams/wells aka Beaver’s fever or Backpacker’s Diarrhea
What is the pathophysiology of Giardia Lamblia diarrhea?
Beavers are the reservoir for the protozoa. Outbreaks occur due to contaminated water or fecal-oral transmission
Symptoms of Giardia Lamblia
Frothy, greasy foul-smelling diarrhea (steatorrhea) with no blood or pus
Abdominal cramps
Bloating
Malabsorption with chronic diarrhea
Treatment for Giardia Lamblia
- Rehydration
- Metronidazole, Albendazole, Tinidazole
However, what treatment is used in children for Giardia Lamblia?
-Furazolidone
Amebiasis, caused by Entamoeba histolytica, is not common in the US. However, it is also associated with
Amebic liver abscesses
What are some symptoms of amebiasis?
Mild diarrhea to severe dystentery
RUQ pain, fever, anorexia (if abscess)
What are some diagnostics that should be done for amebiasis?
- Stool microscopy (Ova and parasites): cysts with ingested RBCs. Do 3 on different days because cysts are not constantly shed
- Antigen testing (ELISA)
- Stool PCR: parasitic DNA in stool
- Liver abscess: US, CT, MRI
For amebiasis colitis, what treatment should be given?
Metronidazole then Paromomycin, Diloxanide, or Diiodohydroxyquinoline
For a liver abscess associated with amebiasis, what treatment should be given?
-Metronidazole + intraluminal anti parasitic (Paromomycin, Diloxanide, etc.) then Chloroquine
Finally, an asymptomatic infection of amebiasis should be treated with what?
-Intraluminal agent alone (Paromomycin, Diloxanide, or Diiodohydroxyquinolone)
What are some common etiologies of secretory diarrhea?
- Hormonal: serotonin (carcinoid syndrome), calcitonin (medullary thyroid cancer), gastrin (Zollinger-Ellison Syndrome)
- Laxative abuse
- Vibrio Cholerae
On a workup, what is seen with secretory diarrhea?
- Normal osmotic gap
- Large volume
- No change in diarrhea with fasting
What are some common etiologies of osmotic diarrhea?
- Medications: Antacids, Lactulose
- Bacterial overgrowth
- Malabsorption: Celiac disease, lactose intolerance
On a workup, what is seen with osmotic diarrhea?
- Increased osmotic gap
- Decreased diarrhea with fasting
- Increased fecal fat
- Deficiency in fat soluble vitamins
