II-A. Systemic bacteriology | 17. Brucella and Francisella genus Flashcards
I. Brucella genus
1. What are the features of Brucella genus?
Gram-negative coccobacilli / short rods
I. Brucella genus
2. What are important species of Brucella genus?
species were named based on host animal
* B. melitensis – goat, sheep
* B. suis – swine
* B. abortus – cow
* B. canis - dog
I. Brucella genus
3. What is the route of transmission of Brucella genus?
route of transmission: zoonosis!
- bacterium spreads with animal secretions, milk ( pasteurisation can kill them!)
I. Brucella genus
4. What is the entry site of Brucella genus?
Entry site: infection through skin/mucous membrane lesion (alimentary)
- bacteria infects RES, can be found intracellulary → granulomas
I. Brucella genus
5. What is the disease caused by Brucella genus?
brucellosis (“great imitator”) – aspecific symptoms
I. Brucella genus
6. What are the symptoms of brucellosis (“great imitator”) – aspecific symptoms?
fever (FUO), insomnia, irritability + organ dysfunctions
I. Brucella genus
7. Can brucellosis infect organs
- spleen abscess, liver abscess, granulomas
- lymphadenopathy, blood stream infection, endocarditis
- cerebral abscess, meningitis, osteomyelitis
- orchitis, chorioretinitis
I. Brucella genus
8. What are infections caused by Brucella genus?
- febris melitensis (maltan fever) → B. melitensis
- febris undulans (Bang-disease) → B. abortus
I. Brucella genus
9A. How do we diagnose Brucella genus?
- aspecific symptoms, might imitate anything ➡ should think about it (farm workers, unpasteurized dairy product consumption!)
- sampling
- laboratory
I. Brucella genus
9B. How do we sample to diagnose Brucella genus?
blood culture, aspirate (lymphnodes), bone marrow, blood (for serology)
I. Brucella genus
9C1. How do we do laboratory to diagnose Brucella genus?
- serology (tube agglutination, ELISA, IF)
- Wright-tube agglutination: patient serum is mixed with known Brucella bacteria ➡ if agglutination happens, it proves, that the patient has antibodies against the bacterium) - PCR
- culturing (rarely, only in specific laboratories)
I. Brucella genus
9C2. What is Wright-tube agglutination?
Wright-tube agglutination: patient serum is mixed with known Brucella bacteria ➡ if agglutination happens, it proves, that the patient has antibodies against the bacterium)
I. Brucella genus
10. What is the empirical therapy for Brucella genus?
- tetracyclines + rifampicin
- aminoglycosides
I. Brucella genus
10. What is the prevention for Brucella genus?
- vaccination of livestock
- pasteurization of dairy products
- category B bio-weapon!
II. Francisella genus
1. What are the features of Francisella genus?
- Gram Negative (-)
- Small rod or coccobacilli
- Facultative intracellular
(category A bio-weapon!)