Case Study - Cholera A 25 year old woman is brought into aclinic in Bangladesh during the monsoon season. She is almostcomatose, her pulse is weak and she is experiencing tachycardia.She has severe diarrhea, and is producing watery stool at a rate of950 ml/hr. Her skin appears shriveled, and when a fold of skin ispinched it remains so for several minutes. Microscopic examinationof the patient’s stool reveals the presence of a large number ofVibrio cholerae bacteria. The patient cannot drink, so intravenousisotonic NaCl is administered. When the patient is conscious, sheis given an oral rehydration solution to drink. It contains NaCl,KCl, NaHCO3 and glucose. After 5 days she is sufficiently recoveredto leave the hospital.
1. How did she most likely encounter the bacteria?
2. Why does she exhibit weak pulse and tachycardia? Why is shealmost comatose?
3. How did the cholera toxin enter the cells and how did itaffect intracellular signal transduction pathways and membranetransport.
4. How do intravenous fluids immediately improve the patient’scondition? Why isotonic NaCl?
5. What is the rationale for the ingredients in the oralrehydration solution?
6. Why does the patient recover in 5 days with this treatmentand without antibiotics?
