Summarize the following text to main points and sub-points and make detailed explain for them:

nce of sodium nitroprusside as a coupling agent to yield a green 
chromophore. The intensity of the color formed is proportional to the 
concentration of urea in the sample. 
          Urea + H2O
𝑈𝑟𝑒𝑎𝑠𝑒
ሱ⎯⎯⎯ሮ2𝐻2𝑂 + 𝐶𝑂2   
There are several methods for determination of urea 
1. Enzymatic methods. 
2. Urease \ glutamate dehydrogenase. 
3. Dry chemistry. 
4. Diacetyl monoxime. 
4.1.11 Interference 
1. Bilirubin interference was tested up to 20 mg/dl and found not to interfere.  
2. Highly lipemic samples may cause absorbance errors and the sample must be 
diluted. 
3. Haemolysis interference was tested up to 500 mg/dl and found not to interfere. 
4. Great care must be taken to prevent ammonia contamination of the specimens 
to be analyzed for urea. Ammonia in the atmosphere, in the room, in the water 
or the reagent will elevate test results. 
5. Antibiotics, Tetracycline, Gentamicine, Vancomicine. 
 
 
 
 
 
 
155 
 
13.SERUM CREATININE 
ﻛﻴﻤﻴﺎﻭﻱ ﺃﺧﺘﺼﺎﺹ ﺧﺎﻟﺪ ﻧﺠﻢ ﻧﺬﻳﺮ
 
ﺭﺋﻴﺲ ﺗﻘﻨﻲ ﻃﺒﻲ ﺍﺧﺘﺼﺎﺹ ﺳﺎﺭﺓ ﻣﺤﺴﻦ ﻣﺤﻤﺪ
 
4.2 Introduction  
Creatinine is a chemical waste product in the blood that passes 
through the kidneys to be filtered and eliminated in urine their synthesis 
requires three amino acids, methionine, glycine, and arginine. The 
chemical waste is a by-product of normal muscle function. The more 
muscle a person has, the more creatinine they produce. Levels of 
creatinine in the blood reflect both the amount of muscle a person has and 
their amount of kidney function. Women usually have lower creatinine 
levels than men because women, on average, have less muscle than men 
see table (2-1). Other factors that may affect the level of creatinine in the 
blood include body size, activity level and medications. A creatinine 
blood test doesn’t require much preparation. Fasting isn’t necessary can 
and should eat and drink the same as do normally to get an accurate 
result. 
4.2.1 When to conduct the examination 
1. To diagnosis, monitoring and treatment of kidney disease. 
2. To screen for kidney disease diabetes, high blood pressure or other 
conditions that increase the risk of kidney disease. 
3. To monitor the function of transplanted kidney. 
Table (2-1): Average reference ranges for adult males and females. 
 
Average creatinine 
levels (μmol/L) 
Average creatinine 
levels (mg/dL) 
Adult male 
60–110 
0.7–1.2 
Adult female 
45–90 
0.5–1.0 
 
During pregnancy, blood flow to the kidneys is higher. This 
increases trusted Source a person’s GFR and the rate of creatinine 
 
156 
 
13.SERUM CREATININE 
ﻛﻴﻤﻴﺎﻭﻱ ﺃﺧﺘﺼﺎﺹ ﺧﺎﻟﺪ ﻧﺠﻢ ﻧﺬﻳﺮ
 
ﺭﺋﻴﺲ ﺗﻘﻨﻲ ﻃﺒﻲ ﺍﺧﺘﺼﺎﺹ ﺳﺎﺭﺓ ﻣﺤﺴﻦ ﻣﺤﻤﺪ
 
excretion. Due to this, pregnant people typically have lower levels of 
blood creatinine.  
4.2.2 Abnormal results 
A. A Higher than normal level may be due to: 
1. Blocked urinary tract 
2. Kidney problems such us kidney damage or failure, infection 
3. Loss of body fluid (dehydration) 
4. Muscle problems. Such us breakdown of muscle fibers 
5. Problems during pregnancy such as seizures caused by eclampsia 
or high blood pressure caused by preeclampsia. 
B. A lower than normal level may be due to: 
1. Conditions involving the muscles and nerves that lead to 
decreased muscle mass. 
2. Malnutrition. 
3. Creatinine decrease in old age because increased catabolism of 
muscle. 
4. Creatinine interference with some drugs and decrease when used 
cephalosporin. Cephatoxim. 
4.2.3 Causes of abnormal plasma urea: creatinine ratio 
A. Increased 
1. High protein intake. 
2. Gastrointestinal bleeding. 
3. Hypercatabolic state. 
4. Dehydration. 
5. Congestive cardiac failure. 
6. Urinary stasis. 
7. Muscle wasting. 
8. Amputation. 
 
157 
 
13.SERUM CREATININE 
ﻛﻴﻤﻴﺎﻭﻱ ﺃﺧﺘﺼﺎﺹ ﺧﺎﻟﺪ ﻧﺠﻢ ﻧﺬﻳﺮ
 
ﺭﺋﻴﺲ ﺗﻘﻨﻲ ﻃﺒﻲ ﺍﺧﺘﺼﺎﺹ ﺳﺎﺭﺓ ﻣﺤﺴﻦ ﻣﺤﻤﺪ
 
B. Decreased 
1. Low protein intake. 
2. Dialysis. 
3. Severe liver disease. 
4.2.4 Instances when creatinine alone can be used to determine 
kidney function 
This is an important question. There is a difference between looking 
at creatinine in the bloodstream (called “serum creatinine”) and looking at 
creatinine in urine (called “creatinine clearance”). These are two different 
lab tests. Serum creatinine is part of a routine lab report; creatinine 
clearance is not. 
Creatinine clearance requires a timed urine sample. All the urine has 
passed within a specific time period – usually 24 hours – is saved 
(collected) in a container and tested. The result shows how much 
creatinine has passed through the kidneys into the urine. It helps show 
how well kidneys are removing the waste products from the blood. 
Creatinine Clearance test: Is the ability of the glomerular to filters 
the substances from the blood its depended on the rate of filtration and its 
24hr urine collection to measure creatinine. 
𝐂𝐫𝐞𝐚𝐭𝐢𝐧𝐢𝐧𝐞 𝐂𝐥𝐞𝐚𝐫𝐚𝐧𝐜𝐞= Creatinine 𝑢𝑟𝑖𝑛𝑒
Creatinine 𝑠𝑒𝑟𝑢𝑚
× 𝑉𝑜𝑙𝑢𝑚𝑒𝑢𝑟𝑖𝑛𝑒(𝑚𝑙)
𝑇𝑖𝑚𝑒(ℎ𝑜𝑢𝑟𝑠) × 60 
Typical creatinine clearance for healthy adult = 80 - 120 ml/min 
 
 
 
158 
 
14.TOTAL SERUM PROTEIN  
ﺩ.ﺳﻬﺎ
ﺩ ﻓﺎﻟﺢ ﺣﺴﻮﻥ
 
ﺩ.ﻣﺤﻤﺪ ﻋﺒﺪ ﺍﻟﺠﻠﻴﻞ ﺯﻳﺎﺭﺓ
 
4.3 Serum and Plasma Protein 
Introduction 
Proteins are present in all body fluids, but it is the 
proteins of the blood plasma that are examined most frequently 
for diagnostic purposes. More than 100 individual proteins have 
a 
physiological 
function 
in 
the 
plasma. 
Their 
principal 
functions, with relevant examples, are indicated in Table (4-1). 
Table (4-1): Functions of Plasma Proteins 
Functions  of  Plasma Proteins 
 
 
Transport 
- Thyroxin-binding globulin     
  (thyroxin hormone) 
- Apolipoproteins   
  (cholesterol, triglyceride) 
- Transferrin (iron) 
 
Humoral immunity 
- Immunoglobulins 
Maintenance of oncotic pressure 
- All proteins, particularly albumin 
 
Enzymes 
- Renin 
- Coagulation factor 
- Complement proteins      
Protease inhibitors 
- α₁-antitrypsin (acts on proteases) 
 Buffering 
- All proteins 
Some plasma proteins are enzymes (e.g. renin, coagulation 
factors). In addition to these, many primarily intracellular enzymes are 
detectable in plasma as a result of their loss from cells during normal 
cell turnover. The measurement of such enzymes provides a sensitive 
(although often relatively non-specific) indicator of tissue damage. 
4.3.1 Metabolism of proteins 
The amount of protein in the vascular compartment depends on the 
balance between the rates of synthesis and catabolism or loss. However, 
also important is the relative distribution between the intravascular and 
extravascular compartments, as the concentration depends on the relative 
amounts of protein and water in the vascular compartment.  
 
159 
 
14.TOTAL SERUM PROTEIN  
ﺩ.ﺳﻬﺎ
ﺩ ﻓﺎﻟﺢ ﺣﺴﻮﻥ
 
ﺩ.ﻣﺤﻤﺪ ﻋﺒﺪ ﺍﻟﺠﻠﻴﻞ ﺯﻳﺎﺭﺓ
 
4.3.1.1 Protein synthesis  
Hepatocytes synthesize many plasma proteins; those of the 
complement system are also made by macrophages. Immunoglobulins are 
mainly derived from the B lymphocytes of the immune system. The 
concentrations of several proteins are used as a measure of hepatic 
synthetic function. 
4.3.1.2 Protein catabolism and loss  
1. Most plasma proteins are taken up by pinocytosis into capillary 
endothelial cells or mononuclear phagocytes, where they are 
catabolized.  
2. Small molecular weight proteins are lost passively through the renal 
glomeruli and intestinal wall.  
3. Some are reabsorbed, either directly by renal tubular cells or after 
digestion in the intestinal lumen. 
4.3.2 Measurement of Plasma Proteins 
In very general terms, variations in plasma protein concentrations can 
be caused by changes in any of three factors: 
1. The rate of protein synthesis 
2. The rate of removal       
3. The volume of distribution  
The concentration of proteins in plasma is affected by: 
A. Posture:  an increase in the concentration of 10–20% occurs 
within 30 min of becoming up right after a period of 
recumbency.  
 
160 
 
14.TOTAL SERUM PROTEIN  
ﺩ.ﺳﻬﺎ
ﺩ ﻓﺎﻟﺢ ﺣﺴﻮﻥ
 
ﺩ.ﻣﺤﻤﺪ ﻋﺒﺪ ﺍﻟﺠﻠﻴﻞ ﺯﻳﺎﺭﺓ
 
B. Tourniquet: if it is applied before venipuncture, a significant 
rise in protein concentration can occur within a few minutes.  
In both cases, the change in protein concentration is caused by 
increased diffusion of fluid from the vascular into the interstitial 
compartment. These effects must be borne in mind when blood is 
being drawn for the determination of protein concentration. Causes of 
increased and decreased total plasma protein concentration are 
summarized in Table (4-2).  
Table (4-2): Causes of Changes in Total Plasma Protein Concentration. 
Increase  
Hypergammaglobulinaemia. 
paraproteinaemia 
↑ Protein synthesis. 
artefactual 
Haemoconcentration caused by stasis. 
of blood during venepuncture. 
dehydration 
↓volume of distribution. 
Decrease  
Malnutrition and malabsorption. 
 liver disease humoral 
immunodeficiency 
↓ Protein synthesis. 
Over hydration. 
 Increased capillary permeability. 
↑ Volume of distribution. 
Protein-losing states. 
Catabolic states. 
↑ excretion/catabolism 
 
 
161 
 
14.TOTAL SERUM PROTEIN  
ﺩ.ﺳﻬﺎ
ﺩ ﻓﺎﻟﺢ ﺣﺴﻮﻥ
 
ﺩ.ﻣﺤﻤﺪ ﻋﺒﺪ ﺍﻟﺠﻠﻴﻞ ﺯﻳﺎﺭﺓ
 
4.3.3 Methods of A

Summary :