Pathology Notes

Infectious gastroenteritis Updated: 01/26/2024 © Jun Wang, MD, PhD   General features Inflammation of GI tract Most commonly caused by viruses May be associated with bacteria, fungi or parasites Fecal-oral transmission: foodborne, waterborne Most important risk factor: poor hygiene and sanitation Presentations: abdominal pain, nausea/vomiting, diarrhea Mild cases Most common Likely self-limited Supportive therapy only Severe cases May cause dehydration and sepsis   Diarrhea vs. Dysentery Diarrhea o    Passage of loose or watery stools o    At least 3 times in a 24-hour period o    Increased water content due to impaired water absorption or active water secretion, with or without mucosa injury or inflammation o    Acute: < 14 days; Persistent: 14-30 days; Chronic: > 30 days Dysentery o    AKA invasive diarrhea o    Diarrhea with visible blood or mucus o    Commonly associated with fever and abdominal pain   Types of diarrhea Secretory o   

Shock Updated: 08/08/2022 © Jun Wang, MD, PhD General features Cell/tissue hypoxia Due to circulatory failure Life threatening Reversible at early stage only Need to initiate therapy immediately while rapidly identify underlying etiology Treat underlying etiology Stages Compensation : Perfusion of vital organs maintained Decompensation : Hypoperfusion and lactic acidosis Irreversible : Permanent cell/tissue damage, organ failure, usually leads to death Classification Distributive : Relative hypovolemia due to pathological redistribution of intravascular volume, usually resulted from excessive vasodilation Systemic inflammatory response syndrome Septic shock Neurogenic shock Anaphylactic shock Drug and toxin-induced shock Endocrine shock Cardiogenic : Cardiac malfunctioning associated critical reduction of pumping capacity Cardiomyopathic Arrhythmic Mechanical Hypovolemic : Absolute hypovolemia due to loss of intravascular volume, usu