Misc body sites (Eye and Body Fluids) Flashcards
What are the three syndromes associated with eye infection?
Conjunctivitis, bacterial keratitis, bacterial endopthalmitis
Source is usually direct inoculation of exogenous organism from fomites, hands, environment or hematogenous spread
Conjunctivitis
Corneal infections include prior ocular disease, contact lens wearers, and topical corticosteroids.
Bacterial keratitis
Most serious; from trauma (including surgery) to the eye
Bacterial endophthalmitis
What are the specimen types for eye cultures?
swab, corneal scrapings, conjunctival scrapings, and vitreous fluid
Potential Pathogens for bacterial endophthalmitis?
All isolates should be considered significant
What is common contaminating flora for all eye cultures?
Coagulase negative staph
Diphtheroid bacilli
Viridans strep
What is the rule to determine the workup flow for eye cultures?
Rule of 3
An oddball organism that is considered on the rise for causes of eye infections?
Acanthamoeba sp (parasite)
T or F. Drainages are sterile fluids.
False
When is a critical value reported for a body fluid culture?
Any time an organism is seen in a gram stain
Of the collection tubes for CSF, which tubes go to micro for testing?
2 and 3
What kind of body fluids culture do we use thioglycolate broth for?
peritoneal dialysis fluids, bone marrows, and CSF shunt fluid
What method do we use for a direct gram stain of body fluids?
CYTOSPIN
T or F? You can refrigerate CSF.
False
What plate do we use for culture of Non-CSF fluid, that we don’t use for CSF fluid?
MAC
If one organism is observed per oil immersion field, then at least how many organisms are there per mL or specimen?
10^5
If you want to submit a body fluid culture in a blood culture bottle, what extra things will you need to do?
Ensure anticoagulant is added to the bottles, and submit extra fluid for gram stain
What are the cons of sending body fluids in blood culture bottles?
No quantitation, certain organisms require blood to grow, and lab must validate
What are the pros of sending body fluids in blood culture bottles?
Bottles w/ additives that neutralize antimicrobials, better recovery using larger inoculum, recommended by ASM, JMC, and numerous studies
What are potential contaminants of non-CSF body fluid culture?
Coag negative staph, Diptheroid bacilli, and Viridans strep
What rule is followed when working up pathogens from a non-CSF body fluid?
Rule of 3; > 3 semiquantitate all and list descriptive IDs
Where is CSF found?
Around the brain in the subarachnoid space and in the spinal cord
Minimizes the passage of infectious agents into CSF.
Blood brain barrier
Infection in the subarachnoid space
Meningitis
Many PMNs (neutrophils) in CSF
Purulent
What kind of infection is purulence indicative of?
Bacterial infection
Usually viral
Increase in CSF lymphocytes
Aseptic
What does a low glucose indicate?
Infection is present and bacteria are feeding on glucose
Potential pathogens of the CSF in neonates and infants?
S. agalactiae (Group B Strep), E. coli, and Listeria monocytogenes
Potential pathogens of the CSF in children?
H. influenzae, S. pneumoniae, N. meningitidis
Potential pathogens of the CSF in young adults?
N. meningitidis
Potential pathogens of the CSF in adults?
S. pneumoniae, N. meningitidis
Potential pathogens of the CSF in elderly?
S. pneumoniae, L. monocytogenes, GNB
Potential pathogens of the CSF in AIDS patients?
Cryptococcus neoformans
Fever
Stiff neck
Change in mental status
Symptoms of acute meningitis
Increased PMN leukocytes
Decreased glucose in CSF
Increased protein in CSF
Findings in bacterial meningitis
Often occurs in
patients who are immunocompromised.
Chronic meningitis
What are the symptoms of chronic meningitis?
The same as acute meningitis
Increase in lymphocytes
Elevated protein
Decreased glucose
Findings in chronic meningitis
Inflammation of the peritoneum membrane
Peritonitis
What patients are particularly susceptible to peritonitis?
End stage renal patients
What are common agents of peritonitis?
Bowel flora/anaerobes, often polymicrobial
What other complication may occur along with pericarditis?
Myocarditis
What is pericarditis usually caused by?
Viral agents
Inflammation of the joint space
Arthritis
Common causes of septic arthritis?
- N. gonorrhoeae – most common in young adults
- Haemophilus influenzae in young children
- Streptococci
- Anaerobic bacteria (Bacteroides)
When might it be necessary to culture a bone marrow aspiration or biopsy?
To diagnose brucellosis, histoplasmosis, blastomycosis, tuberculosis, and leishmaniasis
Where is bone marrow aspirated from?
Interstitium of the iliac crest
What do we collect bone marrow in for culture?
Sodium Polyethanol Sulfonate (SPS)
What are the potential contaminants of all body fluids?
Coag negative Staph, Diptheroid bacilli and Viridans strep
