DIAGNOSTIC TESTS Flashcards
what is the diagnosis of diabetes mellitus based on?
result of blood tests measuring plasma glucose
for a Fasting Plasma Glucose diagnostic test, how long must the person fast for?
8 hours
what is the mmol/L (fasting plasma glucose) for normal, impaired FPG, and diabetes?
normal: <6.0 mmol/L
impaired FPG: 6.1-6.9 mmol/L
diabetes: >7.0 mmol/L on 2 occasions
do you need to fast for a range plasma glucose test?
NO - can be done w no regard to time or last meal
what is the mmol/L if you have diabetes (range plasma glucose test)?
> 11.1 mmol/L + clinical manifestations
what does oral glucose tolerance test (OGTT) measure?
measures plasma glucose to 75g concentrated glucose solution at 2 hours post glucose load
what is the mmol/L if you have diabetes(oral glucose tolerance test (OGTT))?
11.1 mmol/L
what does glycated hemoglobin (A1C) test measure?
measures proportion of glycated hemoglobin in circulation
- reflects average plasma glucose over past 2-3 months - can be taken anytime of day- avoids problems of day to day variations
what is the mmol/L if you have diabetes (glycated hemoglobin A1C)?
> 6.5%
what is the capillary blood glucose monitoring?
- gold standard
- use capillary blood by pricking finger/forearm - blood is placed on strip, strip is entered into a glucometer to determine capillary blood glucose
what blood is used in a capillary blood glucose monitoring test?
whole blood is used which gives results that are 10-15% lower then when blood plasma is used in lab tests
what is the hemoglobin A1C test?
-standard in care of management of diabe†es
-measures glycosylation of hemoglobinby glucose to provide an index of blood glucose levels over a course of 6-12 weeks
When glucose enters the RBC, does it require insulin? Why or why not?
NO
- therefore, the rate at which glucose becomes attached to Hg is dependent on blood glucose levels
what happens during a RBCs 120 lifespan?
they become glycated to form HbA1b, HbA1a and HbA1c (A1C)
is glycosylation of Hg reversible?
NO
- and individuals with hyperglycaemia will have a higher % of glycosylated
why is HbA1c (A1C) useful in screening?
screens for chronic hyperglycaemia and assessing effectiveness of therapy
what are urine tests measured in?
glucose or ketones
what happens in poorly controlled diabetes (urine)?
hyperglycaemia will persist and when renal threshold is reached - results in glycosuria
what are ketones and what occurs with them (urine)?
- ketones are the metabolic end products of fat metabolism
- ketones are completely metabolized BUT when fat metabolism is main source of energy, excessive amounts of ketones are formed and excreted through urine
- occurs in diabetic ketoacidosis
