Microbiology- Bacterial Infections Flashcards
What is reactive arthritis?
An immunologic response caused from bacteria elsewhere in the body.
True or False: In reactive arthritis, bacteria in the joint cause the symptoms.
False. The bacteria are elsewhere in the body.
What are the 2 common triggers of reactive arthritis?
enteric infections (Jack in the Box) and STI’s (Jack in the Butt)
Klebsiella infections can cause what type of reactive arthritis condition?
Ankylosing spondylitis
What surface antigen is similiar to Klebsiella Ag’s, which cross-reacts with immune cells to cause ankylosing spondylitis?
HLA B27
What is septic arthritis?
It’s when bacteria in the blood travel and infects the joint DIRECTLY.
What are some common etiolgies of septic arthritis?
trauma, but often unknown
What is the most common bacteria that causes septic arthritis?
staph
What populations are at risk for septic arthritis?
elderly, immunocompromised
Campylobacter- gram stain
negative
Campylobacter- shape
curved or S-shaped
Campylobacter- agar growth
42 degrees on campy agar
Campylobacter- urease test
negative
Yersinia- gram stain
negative
Yersinia- lactose test
non-fermenter
Yersinia- temperature which it’s motile
25 degrees, not 37
Salmonellae- gram stain
negative
Salmonellae- morphology
motile, has flagella
Salmonellae- lactose test
non-fermenter
Salmonellae- oxidase test
negative
Salmonellae- H2S test
+
Shigella- gram stain
neg
Shigella- motility
non-motile
Shigella- lactose test
non-fermenter
Shigella- H2S test
neg
Chlamydia trachomatis- gram stain
neither + or -, it’s an obligate intracellular
Chlamydia trachomatis- iodine stain
+ with inclusion bodies
Chlamydia trachomatis- giemsa stain
+
Chlamydia trachomatis- associated syndrome
Reiter’s syndrome
What are the Sx of Reiter’s syndrome?
conjunctivitis, UTI’s, mucocutaneous lesions. (Can’t see, can’t pee, can’t climb a tree)
To diagnose septic arthritis, synovial fluid is tested +. What type of bacteria could be the causitive agent (in 75% of the cases)?
A gram + bacteria
Neisseria gonorrhea septic arthritis- population
younger, sexually active individuals (75% of the cases)
Neisseria gonorrhea septic arthritis- Sx
fever, pain in multiple joints, multiple skin lesions
Neisseria gonorrhea septic arthritis- synovial fluid culture test
negative
What is the most common cause of non-gonococcal septic arthritis in adults and children?
Staph. aureus
S. viridans and pneumoniae (group B) are secondary to S. aureus and cause what % of the cases of septic arthritis?
20%
What % of untreated lyme disease patients develop arthritis?
60%
Staphylococcus aureus- gram stain
+
Staphylococcus aureus- catalase test
+
Staphylococcus aureus- coagulase test
+
Streptococci- gram stain
+
Streptococci- catalase test
-
What are the 2 beta-hymolytic Streptococci?
pyogenes and agalactiae
S. pyogenes- bacitracin test
sensitive
S. agalactiae- bacitracin test
resistant
What are the 3 alpha-hymolytic Streptococci?
pneumoniae, mutans, intermedius
S. pneumoniae- optochin test
sensitive
Mutans and intermedius- optochin test
resistant
Haemophilus influenza- gram stain
-
Haemophilus influenza- shape
coccobacilli
Haemophilus influenza- Quellung test
+
Haemophilus influenza- culture
chocolate agar, requires X and V factors
Mycobacterium tuberculosis- acid-fast test
+
Mycobacterium tuberculosis- shape
thin rods, non motile
Mycobacterium tuberculosis- aerobic or anaerobic
obligate aerobe
Borrelia burgdorferi- shape
spirochete
Borrelia burgdorferi- tests
giemsa and silver stain
Borrelia burgdorferi- aerobe or anaerobe
microaerophilic
Borrelia burgdorferi- serology
ELISA, western blot
What is osteomyelitis?
infection of the bone and bone marrow
What is the most common bacteria in osteomyelitis?
S. aureus
Osteomyelitis- Tx
diffcult, usually by surgery
What is the epidemiology of acute osteomyelitis in children?
2 cases/10,000 children (typically in lower extremities)
What is the epidemiology of chronic osteomyelitis in the population?
2 cases/10,000 (mostly in diabetics)
What are the 2 routes of infection for osteomyelitis?
hematogeneous, direct spread after injury/surgery
What are the Sx of hematogeneous osteomyelitis?
fever, chills, lethargy, local inflammation
What are the Sx of direct osteomyelitis?
occurs 1 month after trauma/surgery, low-grade fever, pain, drainage, bone necrosis and soft tissue dmg. difficult to Tx.
What are the Sx of chronic osteomyelitis?
chronic local pain, sequestrum (necrotic bone) surrounded by involcrum (new bone sheath)
I wanted
to end at 69 cards
