Upgrade to remove ads
Only $2.99/month

Chemistry HMWK Clinical Week 3

Terms in this set (86)

Initial absorbance is measured followed by a second reading after 5 minutes
Describe a non-kinetic enzyme assay?
Transferase
Enzymes that catalyze the transfer groups between compounds are classified as belonging to which enzyme class?
inactive enzyme
apoenzyme
a biochemically active compound formed by the combination of an enzyme with coenzyme
holoenzyme
a nonprotein compound that is necessary for the functioning of an enzyme
coenzyme
a nonprotein group forming part of or combined with a protein
prosthetic group
No
Do all enzymes have optimal activity at pH 7
The point in an enzyme reaction when the product is formed
In the assay of an enzyme, what is zero order kinetics
340 nm
In enzymatic reactions-NADH has absorbance maximums at what "nm" range
elevated ALP
What causes enzyme levels to increase in cholestatic liver disease
Pernicious anemia & hemolytic disorders
What conditions produces the highest elevation of serum lactate dehydrogenase (LD)?
Elevated LDH: Acute appendicitis
Elevated LDH-5: Crush Injury & Hepatic carcinoma
Elevated LDH-3: Pulmonary infraction
How do the following conditions affect LD levels?
1. Storage of blood at 4 Degrees Celsius for 3 days: Sample can not be tested
2. Storage of blood at room temp. for 24 hrs: Can still be tested
3. Hemolysis during sample collection: Must recollect
4. Use of plasma collected in heparin tube: Can not be tested
How does each of the following conditions interfere with the measurement of LD?
CK is an enzyme is generally associated with ATP regeneration in contractile or transport systems. Its predominate physiologic function occurs in muscle cells, where it is involved in storage of high-energy creatinine phosphate. Because enzyme elevation is found in numerous disorders, the separation of total CK into various isoenzyme fractions is considered a more specific indicator of various disorders than total levels.
What are the properties of CK and the significance of CK isoenzymes?
Low CK activity
How does an endogenous completive inhibitor affect CK result?
Troponin test
What test would be the most useful in diagnosing an AMI?
Duchenne muscular dystrophy
Highest levels of total CK are seen in what disease state?
yes
Are electrophoretic methods for determining CK MB, more sensitive than mass unit assays?
Acute MI: elevated myoglobin & elevated troponin
Skeletal muscle injury: elevated myoglobin and no change troponin levels
Unstable angina: no change myoglobin and elevated troponin
How are plasma myoglobin and troponin used to diagnose the following conditions?
SGPT and SGOT
What are the older abbreviations for ALT and AST?
Alcoholic cirrhosis: elevated transaminases
Obstructive biliary disease: Variable transaminases results
Diffuse intrahepatic cholestasis: elevated transaminases
Acute hepatitis: elevated transaminases
How does each of the following condition affect the serum level transaminases?
Chronic hepatitis
What liver disease produces the highest levels of transaminases?
ALT
Which of the following is more specific for liver diseases, AST or ALT?
Acute pancreatitis, diabetes mellitus, and myocardial infarction
Increased Gamma-glutamyltransferase will be elevated in what disease states?
...
What is the clinical significance of each LD isoenzyme?
...
What disease states are associated with elevated levels of individual isoenzymes?
elevated troponin I level (not specific for AMI)
How is Troponin I level affected when a patient has suffered cardiac injury?
Slightly elevated ALP throughout each ALP
How is the level of serum ALP is affected in pregnant women?
Hemolytic Anemia: No change
Squamous cell carcinoma: Elevated
Acute Myocardial Infarction: Elevated
How is serum alkaline level affected in each of these disease states?
1. Prostatic cancer: Elevated PAP (during metastasized tumor) and Elevated PSA
2. Prostatic Irritation: Elevated PAP and PSA
3. Benign Prostatic Hypertrophy: Slightly Elevated PAP(or no change), Elevated PSA
4. Infection of the Prostate: Variable PAP results, Elevated PSA
What is the clinical significance of prostatic acid phosphate (PAP) and prostatic-specific antigen (PSA) levels for each of the following?
1. elevated AMY levels begin 5-8 hours after onset of attack Peak @ 24-hours, & return to normal levels w/ 3-5 days
2. elevated LPS levels begin 4-8 after attack, peaks @ 24 hrs & drops w/ 8-14 days (more specific)
What is the significance of Amylase and Lipase in the diagnosis of pancreatitis?
1. Focal intrahepatic obstruction: Elevated ALP & GGT
2. Acute Alcoholic Hepatitis: Elevated ALP & GGT
3. Bone disease or Malignancy: Elevated ALP, no change in GGT
How are serum ALP & GGT affected in the following disease states?
Recurrent infections, night blindness, Growth retardation, Abnormal taste response, Dermatitis
Vitamin A
Rickets (children), & Osteomalacia (adults)
Vitamin D
Scurvy
Vitamin C
Mild hemolytic anemia (newborn), RBC fragility ataxia
Vitamin E
Souluble
Is Vitamin B12 soluble or insoluble in water?
Vitamin K
A deficiency in which vitamin leads to prolonged clotting time and may result in hemorrhagic disease in infacy?
Primary-elevated calcium, low phosphorus, not change to potassium
Secondary- decreased normal calcium, decreased phosphorus, no change to potassium
How does Hyperparathyroidism affect serum levels of calcium, phosphorus, potassium?
Tyrosine
Thyroid hormones are derived from which amino acid?
Hyperthyroidism
A patient has a elevated serum T3 and free T4 and a very low serum TSH. What is the most likely cause of these results?
Thyroxine
What is the predominant form of thyroid hormone in the circulation?
Quantitative: Reports concentration of substance in specimen
Qualitative: Provides a positive (drug is present) or negative (no drug) result
What is the significance of Quantitative vs Qualitative analysis of a drug?
Peak: 1 hour after dose administration; IV 30 mins.
Trough: Immediately before next dose
When should blood samples for peak and trough drug levels be collected?
EDTA (purple top)
Which specimen type is the sample of choice for lead screening?
Breast Cancer
CA-15-3
Ovarian Cancer
CA-125
Gastrointestinal Caner, Adenocarcinoma, and Pancreatic Cancer
CA-19-9
Colorectal cancer
CEA
Hepatocellular carcinoma (HCC) & Germ Cell Tumors
Which type of cancer is associated with the highest level of AFP?
Sigmoidoscopy or Colonoscopy or stool based test
What test is recommended as a screening for colorectal cancer in persons over 50 years old?
Conjugated in liver
Bilirubin
Conjugated with glucuronic acid
Conjugated bilirubin
Excreted in the urine of jaundiced patients
Unconjugated bilirubin
Jaundice
What condition is characterized by yellow pigment of skin?
Albumin
What functions as transport protein for bilirubin in the blood?
In the first few days of life
When do newborns with hyperbilirubinemia first exhibit jaundice?
UDP-glucuronyl transferase
What enzyme system catalyzes the conjugation of bilirubin?
Urobilinogen
What reduction product of bilirubin is re-excretion by the liver?
1. Exposure to light: little to no bilirubin
2. Lipemia: Falsely elevated bilirubin
3. Hemolysis: Falsely decreased bilirubin
4. Refrigeration: Can be treated w/ in 24 hours as long as it is protected from light
How do each of the following factors affect the accuracy of bilirubin lab results?
Brain
In the condition Kernicterus, the abnormal accumulation of bilirubin occurs in what tissue
Acute Hemolytic Anemia
What disorders can be classified as a form of prehepatic jaundice?
elevated obstructive bilirubin fraction= obstructive jaundice
What is the relationship between obstructive jaundice and conjugated bilirubin fraction?
ALP,LDH,AST,ALT,ACP, & GGT
What enzymes are frequently assayed to asses liver function?
Blood & Urine, Dexamethasone-suppression test, Saliva test, CT & MRI, Dual X-Ray Absorptiometry (DXA)
What test are used to diagnose Cushing's syndrome?
8 am & 8 pm
If a physician wishes to see whether a patient exhibits normal diurnal rhythm is his or her cortisol secretion, at what time should the specimens be drawn for plasma cortisol determination?
AFP, unconjugated Estriol, and HCG
They are used for screen pregnant women for neutral tube defect, down syndrome
What analytes are measured in a "triple test". What is the significance of performing this test?
Estriol (E3)
Which hormone is often decreased 25% in pregnant women who have a fetus with Down's syndrome?
5-hydroxyindoleacetic acid (5-HIAA)
What is the primary metabolite of serotonin?
Liver
What organ is most affected by toxic levels of Acetaminophen?
It is within range of values seen in smokers; commonly found in smokers
What is the clinical significance of 8% carboxyhemoglobin saturation of whole blood? In what type of individuals is it commonly found?
Cannabinoids (marijuana)
The (tetrahydrocannabinol) is the primary active component of what drug?
Lead poisoning
Free erythrocyte protoporphyrin (FEP) levels are useful as a screening method for what?
Indicates toxic effect of kidneys
What is the importance of having increased trough levels of aminoglycosides in the serum?
Bipolar disorder, Depression & aggressive or self mutilating behavior
What disease state is treated with lithium?
It is found in Cardiac and Skeletal muscle tissue. It is released more rapidly and may be detected as early as 2 hours on AMI. It is highly sensitive but poorly specific.
How does myoglobin relate to an acute myocardial infarction (AMI)?
24 hour
What collection time is required for a quantitative urinary vanillymandelic acid (VMA) test?
Testing for testicular cancer
What is the purpose of measuring urinary human chorionic gonadotropin (hCG) in men?
Atherosclerosis
Increased high sensitivity C-reactive protein can provide the earliest warning of what disease?
BNP is specific for Congestive Heart Failure, therefore: elevated BNP likely in heart failure
How is the BNP used to rule out congested heart failure in persons with symptoms associated with coronary insufficiency?
Heart disease and Artherosclerosis
What disease states are related to high plasma levels of homocysteine?
Gastin
Zollinger-Ellison (Z-E) syndrome is characterized by great elevation?
bone loss
What disease state can occur due to overuse of corticosteroids?
Associated with disease states Hyponatremia (low sodium), Hypo-osmolality (low serum osmolality), Serum bicarbonate stays within range values, Serum K is unchanged, Low anion gap, low BUN, and low uric acid
How does the syndrome of inappropriate antidiuretic hormone secretion (SIADH) affect serum electrolytes?
B1- Beriben (low Thiamine), B2- Chelosis, B6-Eczema,
B12- hematologic effects and macrocytic anemia, B3- diarrhea, Dermatitis and Dementia
Decreased levels of Vitamin B lead to what disease state?
LD 1: elevated with AMI, RBC destruction
LD 2: elevated with AMI, RBC destruction
LD 3: Pulmonary, pancreatitis, lymphocytosis
LD4: elevated with liver and skeletal
LD5: elevated with liver and skeletal
What disease states are associated with elevated levels of LD isoenzymes?
THIS SET IS OFTEN IN FOLDERS WITH...