Francisella Tularensis Flashcards
What animal is tularemia most associated with?
Rabbits and Hares
What bacteria causes tularemia?
Francisella Tularensis
How do humans get infected with F.Tularensis?
Animal contact
Tick/flea bites
What category does F.Tularensis fall into?
Category A
Describe the pathogenesis of Tularemia
Organisms enter through breaks in skin or mucous membrane -> low innoculation needed for infection -> ulcer may develop at entry site -> dissemination to blood stream -> host response with granuloma formation
Describe the characteristics of Tularemia
Facultative Intracellular Small Gram Negative Coccobacilli Bacterial Capsule -> antiphagocytic Strict Aerobe Cellular immunity needed for recovery Requires sulfhydryl for growht Extended incubation time
What is the clinical presentation of Tularemia?
Fever, chills, malaise 2-5 days after exposure
Which areas do rabbit associated tularemia involve?
Fingers and hands
Which areas do tick associated tularemia involve?
Lesions on trunk, perineum, legs, head, neck
What kind of tularemia infection involves papules becoming necrotic and ulcerating ?
Ulceroglandular infections
Can spread to regional lymph nodes and cause swelling
What happens when the eyes are infected?
Oculoglandular Infeciton -> unilateral painful conjunctivitis
How does tularemia lead to typhoidal infection?
Large number of organisms involved-> causes fever, prostration, weight loss,
Has highest mortality
Does tularemia cause pneumonic infections?
Yes
Inhalation of low counts of organisms leading to fever, chills, cough with minimal sputum production and chest pain, dyspnea
What happens in the oropharyngeal form of tularemia?
Occurs with ingestion of infected meat or water Fever, exudative pharyngitis, tonsilitis Pharyngeal ulcers Pseudomembranes Cervical lymphadenopathy
How is Tularemia diagnosed?
Immunofluorescent stain of smears for rapid dx
Needs cysteine for cultures (chocolate agar)
Serologic: Antibody titers
Take for both acute and convalescent -> paired titer
