At what temperature is urine stored and for how long is it stbale?
Urine should be stored at 4 degrees Celsius after collection. It is stable for 1 week at 4 degrees Celsius and for at least 5 months at -80 degrees Celsius. Urine should be stored at 4 degrees Celsius after collection. It is stable for 1 week at 4 degrees Celsius and for at least 5 months at -80 degrees Celsius.
At what temperature does albumin concentration decrease by 0.27 % per day?
-20 degrees celsius
What temperature should refrigerated urine samples be allowed to reach before analysis?
10 degrees Celsius
How many specimens should be assayed and why?
At least 3 separate specimens, collected on different days, should be assayed because of high intraindividual variation and diurnal variation (50% to 100% higher during the day)
What does diagnosis require?
Increased UAE in at least 2 of 3 test measured within a 3-6 month period
What testing methods are used?
Test strips are semi-quantitative assays used for screening
What are some examples of quantitative methods used to screen UAE?
What are the two most common cardiovascular disorders that rely on a biochemical diagnosis?
Epicardium (outermost layer where coronary arteries are found)
Endocardium (innermost layer most susceptible to myocardial ischemia)
What are the 4 chambers of the heart?
Upper chambers (right and left atria)
Lower chambers (right and left ventricles)
A cardiac cycle consists of what two intervals?
Systolic and diastolic
What is systolic pressure?
The blood pressure in the aorta is about 120 mm Hg
What is diastolic pressure?
The blood pressure falls to about 70 mm Hg
What is an electrocardiogram (ECG)?
It records changes in electrical potential and is a graphic tracing of the variation in electrical potential caused by the excitation of the heart muscles.
What is an ECG used to identify?
Used to identify the anatomic, metabolic, ionic, and hemodynamic changes in the heart
What are an ECG’s three major components
Atrial depolarization (p wave)
Ventricular depolarization (QRS complex)
Repolarization (ST segment and T wave)
What is acute coronary syndrome?
Includes individuals who have a variety of forms of unstable ischemic heart disease
What is the major cause of acute coronary syndrome?
What is atherosclerosis?
A diseased caused by plaque (a deposit of fatty material) formed in the inner lining of the coronary arteries that feed the surface of the heart, contributing to significant narrowing of the artery’s lumen.
Atherosclerosis, the abnormal blood flow through the narrowing of an artery is caused by what yellowish substance?
Detection of rise and/or fall of cardiac biomarkers (preferably troponin) above the 99th % of the upper reference limit, together with evidence of ischemic symptoms with at least one of the fallowing symptoms of ECG changes of ischemia changes or new left bundle branch block, development of pathologic Q waves on the ECG, identification of an intracoronary thrombus by angiography or autopsy is criteria for the definition of what?
4 cardiac markers for the diagnosis of acute myocardial infarction are?
AST, SGOT - aspartate aminotransferase
LD - lactate dehydrogenase
CK - total creatine kinase
A condition in which the heart has lost the ability to pump enough blood to the body’s tissue?
Congestive Heart Failure (CHF)
As a result to CHF, the _____ may respond by causing the body to retain fluid (water) and salt.
A common cause of CHF; a disease of the arteries that supply blood and oxygen to the heart causes decreased blood flow to the heart muscles. The heart becomes starved for oxygen and nutrients if the arteries become blocked or severed narrowed. This disease is known as?
Coronary artery disease (CAD)
A common cause of CHF include damage to the heart muscle from causes other than artery blood flow problems such as from infections, alcohol or drug abuse is known as?
These are substances that are released onto the blood when the heart is damaged or stressed.
Measurements of cardiac biomarkers are used to help diagnose ___ ____ ____and ___ ___, conditions associated with insufficient blood flow to the heart as well as CHF.
acute coronary syndrome (ACS)
These are specific proteins found in cardiac muscles and are measured in the diagnosis of myocardial infarction.
Three troponin subunits form a complex that regulate the interaction of actin and myosin and thus regulate cardiac contractions are?
Troponin T (the tropomyosin-binding component)
Troponin I (The inhibitory component)
Troponin C (the calcium-binding component)
Cardiac troponin __ and Cardiac troponin __ are the two main types of troponin used as cardiac biomarkers.
Cardiac troponin I (cTnI)
Cardiac troponin T (cTnT)
Trponins are localized primarily (94%-97%) in the ____ with smaller cytoplasmic fraction.
In general, what is the technique of choice for measuring cTns?
The laboratory should perform biomarkers testing with a maximum turnaround time (TAT) of how long?
1 hour 30 minutes
What term is defines as the time from blood collection to the reporting of results to the provider?
Turnaround time (TAT)
What type of blood specimen appears to be the optimal specimen for rapid processing and testing?
Anticoagulated whole blood or plasma
What two blood tube collection additives interfere with troponin antibody-binding affinity?
This type of cardiac testing is detected by a 32-amino acid polypeptide secreted by the ventricles of the heart in response to excessive stretching of heart muscle cells (cardiomyocytes). The release of this test is modulated by calcium ions.
Brain Natriuretic Peptide (BNP)
The 3 major circulating forms of BNP are?
NT-pro BNP (N-terminal protion or fragment of proBNP)
BNP (C-terminal part of proBNP and the physiological active hormone
What does a normal level of either BNP or NT-proBNP rule out in am emergency setting?
Acute heart failure
True or False
An elevated BNP or NT-proBNP should never be used to rule in acute or chronic heart failure in emergency settings due to lack of specificity
What can be used for screening and prognosis of heart failure?
Either BNP or NT-proBNP
BNP or NTproBNP are typically increased in what kind of patients?
Patients with left ventricular dysfunction, with or without symptoms
BNP accurately reflects what?
Current ventricular status
What is the half-life of BNP?
What is the half life of NT-proBNP?
How are the concentrations of BNP and NT-proBNP measured?
What is the acceptable specimen used for BNP?
EDTA-anticoagulated whole blood or plasma in plastic blood collection tube
What is the acceptable specimen used for NT-proBNP
Serum, heparin-plasma, EDTA plasma collected in either glass or plastic
Where is CK enzyme present? (3)
Heart muscle, skeletal muscle and the brain
Name the 3 isoemzymes of CK
CK1 or CKBB
CK2 or CKMB
CK3 of CKBB
Which CK isoenzyme is the dominant form in the brain and smooth muscle?
CK1 or CKBB
Which CK isoenzyme is sometimes called the cardiac isoenzyme because 10%- 20% of total CK activity in myocardium is from CK-MB?
CK2 or CKMB
Which CK isoenzyme is predominant in both heart and skeletal muscle?
functional capacity of the kidneys and indicative of the number of functioning nephrons.
What is useful about measuring GFR?
targeting treatment, monitoring progression, predicting when renal replacement therapy (RRT) will be required, and as a guide to dosage of drugs excreted by the kidneys to prevent potential drug toxicity.
The renal clearance of a substance is defined as what?
as "the volume of plasma from which the substance is completely cleared by the kidneys per unit of time".
For a substance(s) or marker(s) to be used to measure renal clearance, it must be what 7 things?
1. In stable concentration in the plasma
2. Physiologically inert
3. Freely filtered at the glomerulus
4. Neither secreted
5. Neither reabsorbed
6. Neither synthesized
7. Not metabolized by the kidney
What is the concept of the renal clearance of a substance?
= U/P x V (mL/min) x 1.73/A
What are U,P, V, 1.73, and A stand for?
U= concentration of the substance in urine
P = concentration of substance in plasma
V = total volume of urine excreted in 24 hrs
converted to mL/min
1.73 = body surface area in square meters
A = body surface of patient obtained from
patient’s height and weight (nomogram)
What markers have been used to estimate clearance?
A variety of endogenous and exogenous markers.
Low–molecular weight proteins (Cystatin C)
51Cr-ethylenediaminetetraacetic acid (EDTA)
What urinary protein loss is defined?
Increased urinary protein loss (proteinuria) results from any increase in the filtered load, increased circulating concentration of low molecular weight proteins, or decrease in reabsorptive capacity
How is the normal urinary total protein loss?
It is less than 150 mg /24 hours which is mostly albumin (50% to 60%)
What primary part is the predominant protein in urine in the majority of kidney diseases and is accurately and specifically measured using immunoassay techniques?
How is progression of kidney disease leading to loss of function and ultimately to kidney failure?
Accumulation and deposition of extracellular matrix
How many parts pathophysiology of kidney disease are?
Diagnosis and screening for kidney disease
a symptoms or physical sign
systemic disease with the known renal involvement like diabetes mellitus
What is the definition of Acute kidney injury (AKI)?
1. Increase of plasma creatinine by ≥ 0.3 mg/dL
(26 µmol/L) within 48 hours
2. Increase in plasma creatinine to ≥ 1.5 times
baseline, which is known or presumed to have
occurred within the prior 7 days
3. Reduction in urine output (documented oliguria
< 0.5 mL/kg/hr for more than 6 hours
How Chronic kidney disease (CKD) is defined?
Is defined as abnormalities of kidney structure or function, present for more than 3 months with implications for health
What markers used to identify CKD?
These are plasma creatinine, estimated GFR and measured creatinine.
Lowering blood pressure and reduction of proteinuria have been shown to decrease the progression of CKD
What is sevenfold to tenfold greater in patients with CKD?
The incidence of cardiovascular disease
What is characterized as elevated total or low-density lipoprotein (LDL) cholesterol levels, and elevated triglycerides.
It is Dyslipidemia in CKD
What is is also affected in CKD, leading to "adynamic" bone diseases.
Calcium and phosphate metabolism
How Adynamic bone is defined?
bone is associated with low PTH concentration, abnormal calcium balance, hyperphosphatemia, acidosis and the use of high doses of vitamin D analogs.Due to the predominant loss of peritubular fibroblast (specialized cells that produce collagen) within the renal cortex that synthesize erythropoietin, thus causing anemia
How the classic signs of uremia?
The symptoms are progressive weakness and easy fatigue, loss of appetite followed by nausea and vomiting, muscle wasting, tremors, abnormal mental function, frequent but shallow respirations and metabolic acidosis.
What are the most characteristic laboratory findings in Uremic syndrome?
The most characteristic laboratory findings are increased concentrations of nitrogenous compounds in plasma such as urea and creatinine, as a result of reduced GFR and decreased tubular function.
How retention of urea and creatinine and of metabolic acids is followed?
Retention of urea and creatinine and of metabolic acids is followed by progressive hyperphosphatemia, hypocalcemia and potentially dangerous hyperkalemia
Kidneys fail to maintain adequate excretory, regulatory, and endocrine function.At least 90 organic compounds are retained in urea
What are another diseases of kidney?
These are diabetic nephropathy and hypertensive nephropathy.
How is diabetic nephropathy defined?
It is a clinical diagnosis based on the finding of proteinuria (albuminuria) in a patient with diabetes
It is the most common cause of end stage renal disease (ESRD)
What is hypertensive nephropathy
Hypertensive nephropathy considered another accelerating force in the development of ESRD.
What are Glomerular diseases?
What are Interstitial nephritis diseases?