T2 - L1 infection tests Flashcards
What is fever?
- sign of inflammation/infection. - 38 degrees plus is a temperature.
Symptoms: fever- burning up. Chills, sweats, night sweats and rigors.
Raised Inflammatory markers indicates what?
Raised markers support diagnosis, negative markers make infection less likely.
what can LFTs and
U&E’s identify?
1) can indicate biliary sepsis
2) can identify severe sepsis, urinary tract infection
List some inflammatory markers.
CRP <5mg, ESR<0.5, procalcitonin, new e.g. TRAIL IL-6 and IP-10
what does an increased Hb and RCC indicate?
dehydration, chronic hypoxia, and
polycythaemia
what is anaemia?
Hb of < 13 g/dl in males and < 11.5 g/dl in
females
what is normocytic anaemia?
normal-sized red blood cells, but you have a low number of them.
what is normochromic anaemia?
concentration of hemoglobin in the red blood cells is within the standard
range. However, there are insufficient numbers of red blood cells.
will the PCV in a full blood count increase or decrease with anaemia?
(packed cell volume)
decrease
what does a raised WCC indicate?
infection
which LFTs are used to distinguish between hepatocellular damage and cholestatsis?
ALT - Alanine transaminase
AST - Aspartate aminotransferase
ALP - Akaline phosphatase
GGT - Gamma-Glutamyltransferase
which LFT is used to asses the livers excretory function?
bilirubin
What is ESR and what can it be used for?
erythrocyte sedimentation rate
- often arises from inflammation
- can be used to monitor disease every and treatment response in inflammatory disorders such as rheumatoid arthritis.
what does blood culture sampling allow?
- identification of pathogens
- typing of pathogens
- sensitivity testing of the pathogen
what is a disadvantage of blood cultures?
slower than direct detection
what colour blood test tube is used for LFTs?
yellow/gold
what colour blood test tube is used for a full blood count?
purple
what colour blood culture lid is used for aerobic bacteria?
blue lid
what colour blood culture lid is used for anaerobic bacteria?
purple lid
how long is a blood culture incubated for?
5-7 days
if no growth, specimen is negative and discarded
what is the Time-to-positivity (TTP) of blood cultures?
a predictor of the clinical outcome for bacteremia
what colour does a gram-positive stain appear?
purple
what colour does a gram-negative stain appear?
pink
why is sensitivity testing clinically useful?
informs decisions on how much antimicrobial therapy to deliver
what is the limitation od sensitivity testing?
the correlation between antimicrobial sensitivity and clinical response is not absolute.
what is the limitation of direct detection (microscopy)?
Does not give any information on: antimicrobial susceptibility, typing.
why is direct detection using microscopy useful?
Fastest diagnostic method.
what colour blood test tube would be used for antibody testing?
red
what is Seroconversion?
the time period during which a specific antibody develops and becomes detectable in the blood
what is a fourfold rise?
rise in concentration of antibody from one test to the next x4
what is the limitations of antibody testing?
- Is restricted to patients with a detectable anti-body response.
- Is retrospective (often too late to inform therapy decisions).
which immunological test can be used to detect a Mycobacterium tuberculosis infection?
IFN-y release assays
