Diagnostic Studies/Laboratory tests Flashcards
What labs are in the blood clotting studies
Platelet count
Prothrombin time (PT)
Partial thromboplastin time (PTT)
Normal platelets count
150,000 - 400, 000
Potential cause of low platelet count
Autoimmune disorders
Cirrhosis
Sepsis
Hypersplenism
Hemorrhage
Leukemia
Cancer chemotherapy
viral infection
some medications
Potential cause of high platelet count
malignant disorders
polycythemia vera
rheumatoid arthritis
myeloproliferative disease
What are PT/PTT
Used to evaluate how well coagulation factors in coagulation cascade work together
Measure number of seconds it takes for clot to form in a blood sample after reagents are added:
Prolonged results indicate that blood clotting is taking longer than normal
Conditions that cause prolonged PT with normal PTT
Liver disease
vitamin K deficiency
chronic low-grade Disseminated intravascular coagulation (DIC)
Defective factor VII
anticoagulation drug therapy (Warfain)
Condition that cause both prolonged PT and PTT
Defective or decreased factor I, II, V, X
severe liver disease
Acute DIC
Warfarin overdose
Condition that cause normal PT with prolonged PTT
Decreased/defective factor VIII, IX, XI, XII
Von Willebrand disease
Presence of systemic lupus erythematous (SLE) anticoagulant
Labs that can be elevated in pregnancy
Total cholesterol
Triglycerides
Creatinine clearance
TSH (upper limits during pregnancy are lower and based on trimester = 2.5-3.5
Total thyroxine (T4)
What is BUN
indirect measure of renal and liver function
Increased levels of BUN cause
Hypovolemia
Dehydration
Reduced cardiac function
GI bleeding
Starvation
Sepsis
Renal disease
low levels of BUN cause
liver failure
malnutrition
nephrotic syndrome
What is the role of the HDL
removes cholesterol from peripheral tissues and transports to liver for excretion
What are the renal functions tests
BUN
Serum Creatinine
Creatinine clearance
Urine protein/creatinine (PC) ratio
Role of the serum creatinine
indirect measure of renal function
Increased serum creatinine level cause
renal disorders
dehydration
low serum creatinine level cause
debilitation and decreased muscle mass
Role of creatinine clearance
Calculated from serum and 24 hour urine creatinine level to determine rate at which kidneys are clearing creatinine from the blood, reflecting glomerular filtration rate (GFR)
Increase level of creatinine clearance cause
increased muscle mass
exercise
pregnancy
high dietary meat intake
some medications
low level of creatinine clearance causef
impaired renal function
reduced renal blood flow
heart failure
shock
some meds
Role of Antithyroid peroxidase antibodies
used in differential diagnosis of thyroid disorders associated with autoimmune disease
Positive Antithyroid peroxidase
Graves disease
Hashimotos’ thyroiditis
What labs are included in liver function studies
Bilirubin
Albumin
Liver enzymes
Alkaline Phosphatase (ALP)
AST
