Metabolic and Cardiac Diagnostic Labs Flashcards
Diabetes is a disorder of the (…) cells
pancreatic beta cells
What is the normal function of pancreatic beta cells?
secrete insulin in response to glucose intake causing increased cellular glucose uptake
- Which type of diabetes is an acute onset of immune0mediated insulin deficiency related to destruction of pancreatic beta cells?
- When does the onset of this diabetes usually occur?
- type 1 diabetes
- pediatric onset
What does type 1 diabetes require from onset (treatment)?
requires exogenous insulin administration
- What type of diabetes occurs when insulin uptake in cells is impaired and there is a slower destruction of beta cells in the pancreas?
- When does the onset of this diabetes occur?
- type 2 diabetes
- gradual onset - adulthood
How is type 2 diabetes usually treated?
oral medications initially
Which diabetes occurs in pregnancy?
gestational diabetes
What test is used to diagnose diabetes when a fasting or random glucose reading is elevated?
hemoglobin A1c test
What is the hemoglobin A1c test used to monitor?
- control of diabetes
- risk of diabetes-related complications
What makes up 98% of hemoglobin?
hemoglobin A
What makes up 7% of hemoglobin A?
hemoglobin A1
What makes up 80% of hemoglobin A1?
hemoglobin A1c
What is a the component of hemoglobin A1 that combines most easily and strongly with glucose (glycosylated and hemoglobin)?
hemoglobin A1c
What % of A1c does the average person typically have?
5.6
- A percentage of hemoglobin is (…) which is generally slow and (…)
- Because glycosylation is hard to reverse, we can use the (…) percentage to determine the patient’s glucose level over a (…) month period
- glycosylated (sugar attached)
- irreversible
- HgbA1c
- 3 month period
How do you calculate mean plasma glucose?
(35.6 x HgbA1c) - 77.3
What are the hemoglobin A1c values in these individuals?
- non-diabetic adult or child
- pre-diabetes
- diagnosis of diabetes
- goal for most established diabetics
- poor control
- 4.5-5.7%
- 5.7-6.4%
- > 6.5% of total hemoglobin
- <7% (“lucky 7”)
- > 8% of total hemoglobin
By the time someone has been diagnosed with type 2 diabetes, how much of their pancreatic beta cells have they lost?
50%
Every 1% reduction in HgbA1c results in a reduced risk in what conditions?
- diabetes related deaths
- myocardial infarctions
- microvascular complications
- amputations or deaths
What test is used to ascertain functioning of the patient’s pancreas and ability to produce insulin and can help distinguish between type 1 and type 2 diabetes?
C-peptide test
What would the values of the C-peptide test be in type 1 diabetes compared to a person with type 2 diabets?
the C-peptide would be lower in type 1 diabetes due to the pancreas no longer producing insulin adequately compared to an individual with type 2 diabetes where their pancreas still has some insulin function
- What is the precursor of insulin?
- What does this consist of?
- What separates in the beta cells of the Islet of Langerhans within the pancreas?
- proinsulin
- consists of alpha and beta chains with C-peptide as the connector of chains
- the chains of proinsulin
- What is the C-peptide value for someone with type 1 diabetes?
- What is the C-peptide value for someone with type 2 diabtes?
- low c-peptide = pancreas failing to produce insulin
- normal c-peptide = pancreas produces some insulin, but cells have reduced uptake of it for use
What are the top 3 causes of pancreatitis, an inflammatory process that occurs in the pancreas?
- long-term alcohol use or binge drinking (most common)
- gallstones
- high triglyceride levels (>1000) (least common)
- Why does long-term alcohol use/binge drinking cause pancreatitis?
- Why do gallstones cause pancreatitis?
- Why do high triglyceride levels cause pancreatitis?
- catabolism of alcohol causes release of harmful pancreatic enzymes and damage to pancreatic ducts
- results in obstruction of enzymes that would normally be released by GI tract
- high lipid values can cause damage to capillaries and structures of the pancreas
If a patient presents with extreme pain in the epigastric region, nausea, and vomiting, what may they have?
pancreatitis
What test is ordered in the evaluation of abdominal pain and is specifically used to detect pancreas?
amylase level
A pancreatitis patient presents with what symptoms?
- upper abdominal pain that may radiate to the back
- pain is often worse after eating
- fever
- nausea
- vomiting
What enzyme is secreted from the acinar cells of the pancreas which travels through the pancreatic duct into the duodenum?
amylase
- What is amylase involved in?
- When damage occurs to the acinar cells, (…) pours out into the lymphatic system, free peritoneum, and circulatory system
- Damage of the acinar cells can occur (…) cells or from obstruction of the (…)
- catabolism of carbohydrates
- amylase pours out
- within cells (OR)
- obstruction of the biliary tract
- Amylase is (…) cleared by the kidneys, so levels can return to normal within (…) hours of onset of illness or trauma
- Persistent or severe disease can cause persistently (…) levels of amylase
- rapidly cleared
- 12 hours
- elevated levels
What causes an increase in amylase levels?
- acute/chronic pancreatitis
- pancreatic cancer
- bile duct obstruction by gallstone
- cholecystitis
- renal failure (diseased clearance)
- ectopic pregnancy
- mumps
Where else can amylase be found?
- fallopian tubes
- salivary glands
- gallbladder
What is a better level to measure for pancreatitis and is used to diagnose pancreatitis in the evaluation of abdominal pain?
lipase level
- What is lipase secreted by and into?
- What is it involved in?
- When there is damage to pancreatic acinar cells, (…) is released into the circulations and levels become elevated
- What is lipase excreted via?
- secreted by the pancreas into the duodenum
- involved in the catabolism of triglycerides and fatty acids
- lipase
- excreted via the kidneys
- Lipase can be dramatically elevated in pancreatic disease, up to (…) normal level
- What is more specific for pancreatic injury?
- Why is lipase better than amylase?
- Currently, lipase is used to diagnose what?
- 5-10x normal level
- lipase
- lipase rises a little later and sticks around a little longer (5-7 days)
- solely to diagnose acute pancreatitis (without amylase)
- Uric acid is the end byproduct of what?
- What are the building blocks of DNA?
- What do sources of purines include?
- Uric acid that results from purine catabolism is primarily excreted by (…)
- purine nucleotide catabolism
- purines and pyrimidines
- diet, degradation of nucleotides or endogenous synthesis of new purines
- kidneys but also by the intestinal tract
What causes elevated uric acid?
- high animal protein diets (high purine levels)
- alcohol use/abuse (metabolism of alcohol increases uric acid production)
- diuretic use (medications can increase uric acid reabsorption/decrease uric acid secretion in gout
- cancer (increased purine metabolism)
- renal failure (poor excretion of uric acid by kidneys)
Uric acid levels are frequently elevated in (…); this condition is known as (…)
- gout
- hyperuricemia
At levels > 6.8 mg/dl, uric acid can be deposited into (…) in the form of monosodium urate crystals
- joint tissues
What is the name for gout in the first metatarsal and is the most frequent location of gout and is very painful?
podagra
What occurs when the heart is not able to pump blood adequately and perfuse all tissues sufficiently and is complex and multifactorial?
heart failure
What can cause heart failure?
- hypertension
- coronary artery disease
- valvular heart disease
- diabetes mellitus
- congenital heart disease
What generally function to inhibit the reabsorption of sodium in the renal tubule so that sodium excretion in urine is increased?
natriuretic peptides