Bacterial gastroenteritis

Bacterial gastroenteritis

Updated: 01/26/2024

© Jun Wang, MD, PhD

 

General features

  • Infection of bacteria
  • Produce endotoxin and exotoxin
  • Secretory
    • Bacillus cereus: rice
    • Enterotoxigenic E. coli: recent travel
    • Clostridium perfringens: undercooked meat, raw legumes
    • Vibrio cholerae: Sea food, water
    • Staphylococcus aureus: Inadequately refrigerated food
  • Invasive
    • Yersinia: mile, pork
    • Typhi or paratyphi salmonella: recent travel
  • Inflammatory

Endotoxin

  • Components of the cell wall of G-negative bacteria
  • Released by death of bacterial, antibiotics, or antibodies
  • Cause fever: Release of interleukin-1
  • Cause shock: TNF associated hypotension and endothelial damage
  • Release of nitric oxide: Vasodilation, bacterial crossing blood-brain barrier

Extoxin

  • Secreted by both G+ and G- bacteria
  • A/B components
    • B: binds to receptor
    • A: active (toxic)
  • ·Cytolysins
    • Lyse cells by damaging membrane
  • Toxoids
    • Chemical modification
    • Used in vaccines
  • Inhibit protein synthesis
  • Activate immune system: non-specific polyclonal T-cell activation, cytokine releases, etc
  • Promote secretion: activate cAMP pathways, etc
  • Cytolysis: membrane damage, tissue necrosis

Diagnostic approaches

  • CBC
  • Stool tests
  • Stool microbiology tests

o   Culture

o   Molecular tests: More sensitive and rapid than culture

  • Stool microbiology tests recommended when
    • Severe illness: hypovolemia, severe diarrhea and severe abdominal pain
    • Signs of inflammatory diarrhea: fever, stools with blood with or without mucus
    • High-risk host features: old age ≥70 years, severe comorbidities such as heart diseases, immunocompromising condition, inflammatory bowel disease, pregnancy
    • Symptoms persisting for more than one week
    • Public health concerns

Management

  • Fluid and electrolytes replacement
  • Symptom relief
  • Antibiotics: Not needed for self-limited cases
  • Antimotility agents: Usually not indicated

 

 

Back to Infectious gastroenteritis

Back to Contents

Comments

Post a Comment

Popular posts from this blog

Contents

Pathology notes Jun Wang, MD, PhD 1. General information Frequently discussed syndromes Terms of dermatology Terms of hematology 2. Primary immunodeficiency disorders 3. Hemodynamic abnormalities Shock Thrombosis and embolism Bleeding disorders 4. Benign white cell disorders 5. Hematopoietic neoplasms Lymphoid neoplasms Myeloid neoplasms Histiocytic neoplasms: Langerhans cell histiocytosis 6. Cardiovascular system Pulmonary hypertension Cardiovascular system tumors 7. Respiratory tract tumors 8. Gastrointestinal tract Congenital disorders Infectious gastroenteritis Oral cavity Esophagus Stomach Intestinal tumors Salivary glands Exocrine pancreas and gallbladder 9. Urinary system Kidney masses Lower urinary tract 10. Male reproductive system 11. Female genital tract 12. Breast 13. Endocrine organs Pituitary gland Adrenal gland Thyroid gland Parathyroid gland Endocrine pancreas Multiple endocrine neoplasms 14. B
Read more

Female genital tract

Pathology of female genital tract   Updated: 01/23/2024 © Jun Wang, MD, PhD Key anatomic features Opened channel, pathological basis for pelvic inflammatory disease Cervix: exocervix, endocervix, transformation zone Uterus: fundus, body Fallopian tube: intramural, isthmus, ampulla, infundibulum, fimbriae Placenta: umbilical cord, fetal membrane, placenta Key histologic features Stratified squamous epithelium from vulva to exocervix Simple columnar epithelium from endocervix to fimbriae Uterine corpus Endometrium: Glands, stroma Myometrium Perimetrium: Mesothelium/peritoneum Ovaries: three components Epithelium (mesothelium) Stroma Germ cells (follicles) Placenta: Cytotrophoblast, syncytiotrophoblast, intermediate trophoblast Infectious/inflammatory diseases Diseases of vagina and vulva Molluscum contagiosum Lichen sclerosus Paget disease Sarcoma botryoides Squamous cell carcinoma Diseases of cervix Cervical intraepithelial neopla
Read more

Neoplasms of respiratory tract

Neoplasms of respiratory tract   Updated: 11/14/2022 © Jun Wang, MD, PhD Anatomy Nasal cavity Nasopharynx Oropharynx Laryngopharynx Larynx Trachea and bronchi Lungs Histology Squamous mucosa Respiratory mucosa May have abundant lymphoid tissue in pharynx Type I and Type II pneumocytes Key risk factors Human papillomavirus: Squamous cell carcinoma, squamous cell papilloma Epstein Barr virus: Nasopharyngeal carcinoma Smoking Tumors of nasal cavity and nasopharynx Olfactory neuroblastoma Nasopharyngeal angiofibroma Sinonasal papilloma NUT midline carcinoma Nasopharyngeal carcinoma Tumors or tumor like lesions of larynx Vocal cord polyp Squamous papilloma Squamous cell carcinoma Branchial pouch/cleft anomalies Branchial cyst Thyroglossal duct cyst Neoplasms of lung Squamous cell carcinoma Adenocarcinoma Large cell carcinoma Small cell carcinoma Carcinoid Lymphangioleiomyomatosis Neoplasms of pleura Mesothelioma
Read more