Lab results Flashcards
What would it mean if wound swab came back positive for colliforms?
They are colonising flora- not pathological
What do you use to do strep grouping?
Lancefield latex test
What would positive surface antigen represent? e.g. of Hep B
ongoing or previous infection
What would positive surface antibody represent? e.g. Hep B
Immunity
What would core total antibody represent? e.g. Hep B
body starting to respond to infection - shows past/current infection
In terms of antibodies and antigens, would would indicate acute infection of Hep B?
surface antigen +
core total antibody +/-
surface antibody -
In terms of antibodies and antigens, would would indicate past infection and immunity of Hep B?
surface antigen +
core total antibody +
surface antibody +
What rapid test can be done in A&E to check for causes of pneumonia?
Strep pneumo + legionella urine test - looks for antigen
What is normal flora on a genital swab?
lactobacilli and staph aeureus
- staph a is a worry if from retained tampon, penile swap or if heavy and pure
How do you diagnose UTI in catheter users?
not from + dipstick - urine catheters can colonise within 6 hours - must diagnose from symptoms (e.g pyrexia, unwell, confused, increased WCC and CRP)
How would you identify pseudomonas in a culture?
- bacilli
non-lactose fermenting
+ oxidase
What are some commonalities and differences between staph aureus and epidermidis?
both gram + cocci
clusters = staph
+ coagulase = staph aureus (thickens, white, golden clusters on blood agar)
- coagulase = staph epidermidis (white clusters on blood agar)
What do you use to diagnose TB and why?
Ziehl-Neelson stain
TB has high myocolic acid in cell wall so is resistant to gram staining due to high lipid content
What is a gram + cocci chain and alpha haemolytic, not sensitive to optichin? Where does it come from and what can it cause?
strep viridans
from mouth
can cause endocarditis
What are the results that show H. influenza?
gram - bacili
on chocolate agar
