L11 Therapeutics for Diarrhea Flashcards
3 Clinical Types of Diarrhea?
- Acute Watery Diarrhea: hours to days (Includes Cholera)
- Acute Bloody Diarrhea (aka Dysentery):
- Persistent Diarrhea: Last 14 days or longer
4 Major Classifications of Diarrhea?
___________________: Excess water pulled into GI tract due to excessive solutes => diarrhea
___________________: Water and other nutrients cannot pass the intestinal wall as normal
___________________: Contents move through the intestines too quickly for normal absorption
____________________: Epithelial cells in intestines actively secrete more water than they absorb due to pathogenesis => large volumes of fluid diarrhea => rapid dehydration
Osmotic Diarrhea (Lactose Intolerance): Excess water pulled into GI tract due to excessive solutes => diarrhea
Inflammatory/Infectious/Infiltrative Diarrhea (Crohn’s): Water and other nutrients cannot pass the intestinal wall as normal
Abnormal Gi Motility: Contents move through the intestines too quickly for normal absorption
Secretory Diarrhea (Cholera): Epithelial cells in intestines actively secrete more water than they absorb due to pathogenesis => large volumes of fluid diarrhea => rapid dehydration
Classification of Severe Acute Diarrhea?
- profuse watery diarrhea with signs of hypovolemia
- passage of ≥6 unformed stools per 24 hours
- severe abdominal pain
- need for hospitalization
Signs or symptoms concerning for inflammatory diarrhea?
- Bloody diarrhea
- Passage of many small volume stools w/ blood/ mucous
- Temp >38.5
Transmission/Primary Concerns of Cholera Infection?
- Caused by toxin-producing strain of vibrio cholera
- Transmitted through water
- Acute secretory diarrhea/vomitting=> profound fluid/electrolye loss => HYPOVOLEMIC shock (25-50% of severe cases die)
Pathogenesis of Cholera Infection?
Active Transport Disease: Toxin behaves like a hormone that binds intestinal epithelial cells causing them to release excessive amounts of water/electrolytes=> HYPOVOLEMIC shock (25-50% of severe cases die)
Does NOT damage the intestinal mucosa!!
Cholera Pathogenesis?
Cholera produces toxin that binds to CFTR receptor on wall of small intestine => Toxin upregulates cAMP => causes CFTR receptor to remain open => Cl- ions leave the epithelial cell=> Na+ attracted by negative Cl- ions=> w/ more ions in lumen water leaves as well => increased water in small intestines leading to vomitting/diarrhea
Where is there still an active cholera outbreak?
Yemen
General Approach to Therapy for Diarrhea?
REPLATION is VERY important
Solutions of water, salt, and sugar
Oral preferred however Adults w/ severe hypovolemia should receive IV fluids first, then oral rehydration
Fluid Replication/Maintenance Goals?
- Replace 50% in the first 4 hours, 50% in next 20 hours
- Choice of fluid replacement depends on type of fluid/electrolyte loss:
Usually Crystoloid (guided by Urea and Electrolyte result!!) - 25-30mls/kg/day fluid needed for maintenance
- More fluids are needed for Fever/Further fluid loss!
Importance of Zinc/Consequences of Deficiency?
Zinc is vital for protein synthesis, cell growth, and intestinal transport of water/electrolytes
Zn deficiency associated w/ increased risk of GI infections
WHO recommends Zinc supplementation for children with diarrhoea in developing countries
- Reduces severity and dirration of diarrhea
- Reduces likelihood of subsequent infections
Zinc’s Role in Cholera Management?
Inhibits cAMP production!!!!=> blocks cAMP activated K channels => Cl- dependent fluid secretion inhibited
Use of Antibiotics for treating diarrheal Infections?
- Most are _________ infections while _______ diarrhea often resolves quickly
- DO NOT USE ABX in suspected ________________ infection: Releases Shiga toxin => hemolytic-uremic syndrome (HUS)
_________________ preferred therapy when ABX indicated in cases of:
- SEVERE Diarrhea + fever
- Immunocompromised/Elderly
- Invasive (Bloody) Diarrhea
- Public Health Concern
- Most are VIRAL and Bacterial diarrhea usually resolves quickly
- DO NOT USE in suspected Enterohemorrhagic E. Coli (EHEC): Releases Shiga toxin => hemolytic-uremic syndrome (HUS)
Fluoroquinolones (Ciprofloxacin) preferred therapy when ABX indicated in cases of:
- SEVERE Diarrhea + fever
- Immunocompromised/Elderly
- Invasive (Bloody) Diarrhea
- Public Health Concern
Treatment for Severe Campylobacter?
Ciprofloxacin
Treatment for Pregnant woman with suspected Listeria Monocytogenes?
Ampicillin
Causes of Chronic Diarrhea (Developing vs. Developed)
