Typhoid fever
Background
- Not to be confused with typhus, a distinct disease caused by a different genera of bacteria
- Diagnosed in 2% of febrile travelers and caused by Salmonella enterica serotype Typhi (formerly Salmonella typhi) serotype paratyphi A, B, and C[1]
- Endemic in Mexico, Indonesia, Peru, and the Indian subcontinent
- Prior vaccination does not exclude infection
- Incubation period 1-3 weeks with chronic carrier state defined as organism in urine or stool > 12 months
- Chronic carrier state risk factors: biliary tract abnormalities[2]
Diagnosis
Classic symptoms
- Bradycardia relative to fever
Initial symptoms
Subsequent symptoms
- Chills (rarely rigors)
- Cough
- Abdominal distension
- Constipation (more common than diarrhea)
- “Rose spots” – truncal light red macular rash (in the 2nd wk)
- Hepatosplenomegaly
- GI bleeding
- Transaminitis
- Leukopenia with left shift (adults)
- Leukocytosis (children)
Work-Up
- Blood culture
- Urine culture
- Stool culture
- “Rose spot” aspiration
- Bone marrow culture (most sensitive)
- Sensitivity testing for nalidixic acid
Differential Diagnosis
- Viral hepatitis
- Amebic Liver Abscess
- Infectious enteritis
Fever in traveler
- Normal causes of acute fever!
- Malaria
- Dengue
- Leptospirosis
- Typhoid fever
- Typhus
- Viral hemorrhagic fevers
- Chikungunya
- Yellow fever
- Rift valley fever
- Q fever
- Amebiasis
- Zika virus
Treatment
- Consultation with Infectious Disease should be considered since there are increasingly multidrug resistant strains of S. Typhi and coinfection with diseases such as Malaria may complicate treatment. The therapy favors the use of fluorquinolones unless suspected or known resistance.[3]
Antibiotics
Oral therapy with Quinolone Susceptibility
- Ciprofloxacin 500-750 mg PO q 12 hrs x 14 days
Parenteral Therapy with Quinolone Susceptibility
- Ciprofloxacin 400 mg IV q 12 hrs x 10 days
Parenteral Therapy with Quinolone Resistance
- if nalidixic acid resistant, assume fluoroquinolone resistant
- Ceftriaxone 2mg IV q 24 hrs x 14 days
- OR
- Cefixime 10-15 mg/kg IV q 12 hrs x 8 days
Oral Therapy with Quinolone Resistance
- Azithromycin 1 g PO daily x 5 days
Adjunctive Therapy
- If associated delirium, coma, shock, and/or DIC: Dexamethasone 3 mg/kg IV load over 30 minutes, then 1 mg/kg IV every 6 hours x 8 doses
Disposition
- Admit if any complication
Complications
- Small-bowel ulceration
- Intestinal perforation
- Anemia
- DIC
- Pneumonia
- Meningitis
- Myocarditis
- Cholecystitis
- Renal Failure
- Chronic carrier state
Sources
- ↑ Tintinalli et. al. Typhoid Fever. In: Tintinalli et. al. Emergency Medicine A Comprehensive Study Guide. New York, NY: McGraw Hill. 2011. 1082-1084.
- ↑ Hohmann, E. Epidemiology, microbiology, clinical manifestations, and diagnosis of typhoid fever . In: UpToDate. Last updated: July 2013. Accessed July 30, 2014.
- ↑ Bhutta ZA. et al. Current concepts in the diagnosis and treatment of typhoid fever. BMJ. 2006 Jul 8;333(7558):78-82. PDF