MSK Labs Flashcards
What are the inflammatory markers and characteristics of the test
-ESR and CRP
-high in acute and chronic inflammatory states
-sensitive but non-specific
-can monitor disease activity
What is the normal range for ESR
females <15-20 mm/hr
males <10 mm/hr
What does ESR and CRP stand for
erythrocyte sedimentation rate and c-reactive protein
What is the reference range for CRP?
0.0 - 8.0 mg/L
What does an abnormal WBC indicate?
infection or inflammation
-viral can have leukopenia
-bacterial can have leukocytosis with left shift
-sepsis = high or low
What does left shift mean?
relevant to bands = immature neutrophils
What disease is Hgb low in?
anemia, polymyalgia rheumatica
What are the normal ranges for Hgb?
Male: 13.5 - 17.5 g/dL
Female: 12.0 - 15/5 g/dL
What is it called when all CBC values are low?
pancytopenia
What condition is the HLA-B27 often abnormal in?
ankylosing spondylitis
What is elevated in gout and how is it checked?
Uric acid levels elevated, checked through joint aspirate (arthrocentesis) for needle-shaped negatively birefringent crystals
What is the gold standard for diagnosing gout?
Joint aspirate (arthrocentesis) for needle-shaped negatively birefringent crystals made of uric acid
What is present for pseudogout?
rhomboid shaped positively birefringent crystals made of calcium pyrophoshpate dihydrate crystals
What may elevate uric acid levels aside from gout?
high purine intake (after party or vacation)
How long does it take for antibodies to develop after a tick bite?
IgM antibodies to Borrelia burgdorferi: 1-2 weeks
IgG antibodies: 2-6 weeks
What is rheumatoid factor and what is it positive in?
IgM autoantibody
Positive in rheumatoid arthritis, Sjogren Syndrome, SLE, chronic infection, healthy individuals
What is Anti-CCP antibody and what is it associated with?
it is a marker for progressive, erosive joint disease and is highly associated with rheumatoid arthritis (better than rheumatoid factor)
What other labs might support a RA diagnosis?
CBC, ESR, CRP, joint aspirate
What is ANA?
antibody present in many autoimmune disease, looking for a positive result or high titer
What are the common ANA patterns observed under fluorescence?
What lab values may be falsely positive and negative in SLE?
VDRL (syphilis) and RPR or T. Pallidum (syphilis)
What would a CBC likely show in SLE?
pancytopenia
What tests are typically positive in Sjogren’s?
SS-A (Ro) antibody, SS-B (la) antibody
also dry mouth and eyes
What is Creatine Kinase and it’s subtypes?
muscle enzyme
CK-MM = skeletal
CK-MB = cardiac
What is CK used for?
diagnosing and following a muscle problem (elevated in dermatomyositis, polymyositis, polyarteritis nodosa, rhabdomyolysis, regular exercise)
What is aldolase and it’s characteristics?
enzyme found in skeletal muscle, liver, brain
-elevation can indicate muscle breakdown (less specific than CK)
What is Lactate Dehydrogenase (LDH) indicative of?
Cell injury/tissue damage - involving liver, heart, muscles, kidneys, lungs, blood
inaccurate if blood sample hemolyzed
What is the TB Gold test for and its limitations?
serum test for LATENT TB, not impacted by BCG vaccination
limitations: poor sensitivity and specificity for active TB, especially in the presence of HIV
What may be used in multiple myeloma?
SPEP and UPEP (Serum/urine protein electrophoresis) - increase in gamma globulin M protein
What is a D-Dimer indicative of?
Indicates thrombolysis (fibrin degradation product)
-sensitive but not specific
-high negative predictive value
-lots of false positives
What factors are assessed in joint aspirate for infection?
WBC, crystals, gram stain, culture, color/clarity
What is a DEXA scan used for?
determines bone mineral density and helps determine when to start treatment for osteoporosis vs osteopenia
-radiation exposure
What are the 3 main parts of a CBC?
WBC, RBC, platelets
what is reactive lymphocytosis as it relates to WBC?
viral infection
What affects WBC other than infection/inflammation?
prednisone, cancer, chemo
What are some causes of eosinophilia?
wheezes, sneezes, weird diseases
What are bands and what are they associated with?
immature neutrophils associated with bacterial infection
