Description of Medical Condition
An acute infectious disease caused by Vibrio cholerae (El Tor type is responsible for current epidemic, the other type, classic, is found only in Bangladesh). (New serotype now in Bangladesh, India (0139). Important because of lack of efficacy of standard vaccine.) Characteristics include severe diarrhea with extreme fluid and electrolyte depletion, and vomiting, muscle cramps and prostration. Usual course: acute; chronic; relapsing.
Clinical course is 3-5 days, and in the early stages a severely affected patient can lose one liter of fluid per hour
Endemic areas: India; Southeast Asia; Africa; Middle East; Southern Europe; Oceania; South and Central America
System(s) affected: Gastrointestinal
Genetics: N/A
Incidence/Prevalence in USA: 0.01 cases/100,000. The few cases in the U.S. have been in returning travelers or associated with food brought into the country illicitly.
Predominant age: All ages
Predominant sex: Male = Female
Medical Symptoms and Signs of Disease
- Abdominal discomfort
- Anorexia
- Anuria
- Apathy
- Cholera gravis
- Cyanosis
- Decreased skin turgor
- Dehydration
- Diarrhea, painless
- Distant heart sounds
- Diuresis, sudden
- Dysrhythmias
- Fever
- Hypotension
- Hypothermia
- Hypovolemic shock
- Increased or decreased bowel sounds
- Lethargy
- Listlessness
- Malaise
- Non-tender abdomen
- Oliguria
- Rice-water diarrhea
- Seizures
- Sunken eyes
- Tachycardia
- Thirst
- Vomiting
- Washerwoman’s fingers
- Weak peripheral pulses
- Weakness
What Causes Disease?
- Enterotoxin elaborated by gram-negative
- Vibrio cholera (O-group 1)
- Human host
- Contaminated food
- Contaminated water
- Contaminated shellfish
Risk Factors
- Traveling or living in epidemic areas
- Exposure to contaminated food or water
- Person-to-person transmission (rare)
- In endemic areas, children under age 5
- Attack more severe in blood group – as compared to AB
- Individual with low gastric acid secretion
- Gastrectomy
- Individuals on acid-suppressing medications
Diagnosis of Disease
Differential Diagnosis
- Other causes of severe diarrhea and dehydration (e.g., Shigella, E. coli, viruses)
Laboratory
- Stool culture — on selective media (thiosulfate citrate bile salts sucrose [TCBS])
- Typed antisera specific agglutination
- Dark field microscopy — characteristic vibrio motility in stool
- Increased vibriocidal antibodies in unimmunized individual
Laboratory abnormalities of severe dehydration:
- Acidemia
- Acidosis
- Hypokalemia
- Hyponatremia
- Hypochloremia
- Hypoglycemia
- Increased specific gravity
- Polycythemia
- Mild neutrophilic leukocytosis
Drugs that may alter lab results: N/A
Disorders that may alter lab results: N/A
Pathological Findings
- Electron microscopy — organism adherent to mucosa
- Intact mucosa
- Increased cellularity of lamina propria
- Increased cellularity of mucosa
- Vascular congestion
- Lymphoid hyperplasia of Peyer’s patches
- Lymphoid hyperplasia of mesenteric lymph nodes
- Lymphoid hyperplasia of spleen
- Cerebral edema
- Acute tubular necrosis
- Vacuolar hypokalemic nephropathy
- Pulmonary edema
- Hyaline membranes
- Bronchopneumonia
- Focal myocardial damage
- Lipid-depleted adrenals
- Tubularization of zona fasciculata
Imaging
- Abdominal film — ileus
- Chest x-ray — microcardia
Diagnostic Procedures
Physical examination and medical history that includes recent travel
Treatment (Medical Therapy)
Appropriate Health Care
Outpatient for mild cases, inpatient for moderate or severe cases
General Measures
- Determination of the amount of fluid loss (may compare patient’s previous weight to current weight)
- Rehydration therapy. Oral for mild to moderate cases. Patients with severe dehydration may require intravenous replacement.
Activity
Bedrest until symptoms resolved and strength returns
Diet
Small, frequent meals when vomiting stops and appetite returns
Patient Education
- Centers for Disease Control. Traveler’s Information Hotline: (404)332-4559 (available 24 hours via a touch-tone telephone).
- International Association for Medical Assistance to Travelers, 417Center St., Lewiston, NY 14092 (716)754-4883
Medications (Drugs, Medicines)
Drug(s) of Choice
- Oral rehydration therapy, for mild disease:
- Oral rehydration solution (ORS) commercial brands available (Pedialyte, Rehydralyte, Resol, Rice-Lyte) OR
- ORS formula from World Health Organization (WHO)
- per liter:
- Sodium chloride 3.5 grams
- Potassium chloride 1.5 grams
- Glucose 20 grams
- Trisodium citrate 2.9 grams
- Rehydration for severely dehydrated patients:
- IV rehydration (Ringer’s lactate) is followed by oral or nasogastric administration of glucose or sucrose-electrolyte solution
- Antibiotics
- For older children and adults — doxycycline (Vibramycin) — 300 mg once or 100 mg bid for 3 days or tetracycline 50 mg/kg/day for 3 days
- For young children — trimethoprim-sulfamethoxazole (SMX-TMP, Bactrim, Septra) 8 mg/kg trimethoprim plus 40 mg/kg sulfamethoxazole per day, divided q12h. This dosage is equivalent to 1 mL/kg of SMX/TMP suspension. Alternatively, furazolidone (Furoxone) 5-10 mg/kg/day divided q6h for 3 days.
- In pregnancy — furazolidone 100 mgqidx 7-10 days.
Contraindications:
- Tetracycline: not for use in pregnancy or children < 8 years.
- Furazolidone and alcohol may cause disulfiram-like reaction.
Precautions:
- Tetracycline: may cause photosensitivity; sunscreen recommended.
Significant possible interactions:
Tetracycline: avoid concurrent administration with antacids, dairy products, or iron.
Alternative Drugs
N/A
Patient Monitoring
Follow patient until symptoms resolved
Prevention / Avoidance
- Water purification
- Careful food selection, e.g., no unpeeled raw fruits or vegetables, no raw or undercooked seafood
- Enteric precautions
- Tetracycline for contacts
- Natural infection confers long-lasting immunity
- Prophylactic vaccine
- 50% effective for 3 to 6 months
- Not recommended unless required by destination country, and if so, a single dose is sufficient
- Concomitant administration with yellow fever vaccine may result in reduced vaccine response to yellow fever
- Invariably associated with local side effects
- Systemic side effects of fever and malaise
- A new vaccine shows promise, but still in the testing stage
Possible Complications
- Hypovolemic shock
- Chronic biliary infection
- Up to 50% mortality with untreated shock
- Intermittent stool shedding
Expected Course / Prognosis
- Prompt oral or IVtreatment can be lifesaving
- Appropriate disposal of human waste
- Antibiotic treatment reduces duration and infectivity of disease
- Mortality less than 1 % with appropriate supportive care
- Increased mortality with untreated hypovolemic shock
Miscellaneous
Associated Conditions
Increased risk of disease with gastric achlorhydria
Age-Related Factors
Pediatric:
- Breast-feeding is protective against cholera
- Vaccine not recommended for children less than 6 months
Geriatric: N/A
Pregnancy
N/A
Synonyms
- Asiatic cholera
- Epidemic cholera
- Rice water diarrhea
- Cholera gravis
International Classification of Diseases
001.9 Cholera, unspecified
See Also
– Oral rehydration Diarrhea, acute
Other Notes
Centers for Disease Control does not expect a major outbreak of cholera in the U.S., but it has issued a “Cholera Preparedness Plan,” outlining steps for proper surveillance, treatment, laboratory diagnosis, investigation of outbreaks, and public education