Tularemia

#med #disease #y2023

Presentation :

Tularemia usually causes an abrupt onset of nonspecific symptoms, including fever, chills, malaise, and myalgia starting 3 to 5 days following exposure
Ulceroglandular tularemia, typically acquired through tick bite or handling of infected animals, includes an ulcerative skin lesion with central eschar and associated regional tender lymphadenopathy.
Typhoidal presents with systemic illness without indication of the site of inoculation
Pneumonic tularemia, typically acquired through inhalation (or hematogenous spread), includes a dry cough and dyspnea progressing to severe pneumonia
- Develops secondarily in 10-15% of ulceroglandular tularemia cases and in about 50% of typhoidal tularemia cases

Caused by Francisella tularensis via contact with an infected animal (ie hunting rabbits or rodents), through the bite of an infected tick, through inhalational exposure, or ingestion of contaminated food or water.
Tularemia is considered a possible agent of bioterrorism because inhalation of as few as 10 organisms in the form of an aerosol can cause severe pneumonia.

Grows fastidiously in the microbiology laboratory, so the diagnosis is made clinically and using serologic testing

Streptomycin is preferred
- Add chloramphenicol for meningitis
- Alt: Gentamicin IM or IV (for moderate to severe disease), Doxycycline/Cipro (for mild disease)
Note: Relapses can occur in inadequately treated cases.

Case fatality is almost nil in treated cases and about 6% in untreated cases of ulceroglandular tularemia. Case fatality rates are higher for type A infection and for typhoidal, septicemic, and pneumonic tularemia; they are as high as 33% for untreated cases.
- Death usually results from overwhelming infection, pneumonia, meningitis, or peritonitis.