Urinalysis and laboratory tests

The normally collected urinalysis data is divided into two parts; qualitative and quantitative data from urine laboratory tests. As their names suggest, qualitative tests are intended to test the properties of urine such as color, transparency, etc., while quantitative tests try to find the amounts of some indices in urine such as volume, specific gravity, amount of pathological components of urine (blood, proteins, creatinine, etc.).

Qualitative data from urine laboratory tests
color of urine
“On the first day of life of the child, urine is colorless
� On 2.-4. Day – dark reddish, as large amounts of urea are excreted.
“In breastfed infants, the urine is almost colorless until they start drinking fruit juice and eating other foods at 4-6 months of age
“In formula-fed infants, all children and adults, the urine is straw-colored.

Changes in urine color can be physiological. For example?
� Colorless urine is excreted when a person drinks a lot of fluids
� Urine turns orange if the food contains a lot of carotene (carrot);
� Will the urine be pink after eating beetroot?
“Some medications affect urine color. SO, Rifampicin causes the red color of urine, Analginum and Sulfacylamide pink, Mitroxolinum saffron yellow.

Some urine discolorations are of diagnostic value in kidney disease:
� Dark brown urine is a pathognomic symptom of viral hepatitis? the cause of such color is a large amount of bile pigment hyperbiliruburia); characteristic sign is the formation of yellowish foam after shaking such urine.
Smoky brown urine, resembling tea or cola, results from nephron damage when red blood cells cross the basement membrane of the glomerular capsule and lose the hemoglobin. It is the main sign of acute poststreptococcal glomerulonephritis
� Bright red color can be found when “fresh” erythrocytes get into the urine in trauma, renal tuberculosis, crystals, cystitis, urethritis, renal tumor.
� Dark purple discoloration is the sign of significant erythrocyte hemolysis in poisoning, Rh conflict, blood transfusion errors, etc.

Urine may be cloudy only in a newborn for 2-3 days after birth. After that, every healthy person excretes transparent urine. Cloudy, cloudy, dark opalescent urine can be found in the case of a urinary tract infection, an increased amount of crystals, RBCs or WBCs, pus or fats in the urine.

Quantitative data from urine laboratory tests
Diuresis means the process of urine production. The volume of urine (UV per 24 hours) is its laboratory level. Its meaning depends on age.

Pathological changes in urine volume
� Polyuria is diagnosed when urine volume exceeds normal ranges by 2 times or more. It is the common sign of interference with other systems (cardiac edema, diabetes mellitus, diabetes insipidus). Renal polyutia develops in case of backward progression of nephritic edema, chronic renal failure.
“Oliguria means the reduction in daily urine volume to age groups and younger. Renal oliguria is one of the most significant manifestations of renal failure. There may also be extrarenal causes of oliguria, such as B. massive heavy bleeding, diarrhea, poisoning, heart failure, shock. It is very important to identify the cause of oliguria, since when the volume of urine decreases by less than 5% of normal data or there is no urine per day, the treatment plans can be very different. It is one of the most dangerous conditions for the child’s life and needs emergency medical help.
“Anuria can be
1. Kidney – the kidneys do not produce urine due to extensive tissue damage.
2. Postrenal (mechanical) – urine is produced but does not get to the bladder because of an obstruction in the upper urinary tract or bladder neck.

� Nocturia, the normal correlation of daytime and nighttime urine volume is 2:1. This means that with greater fluid intake and physical activity, urine output is more intense during the day. If the volume of night urine is larger, then this is the manifestation of decreased kidney function.

pH of urine
This sign depends on age, dietary habits, prescribed medications, differs both in different people and in a person in different periods.

specific weight
It is the concentration of electrolytes and other substances that dissolve in the urine. A decrease in specific gravity can be observed when drinking a lot of liquid, severe renal failure, back progression of edema, diabetes insipidus. Increasingly observed in oliguria, diabetes mellitus, excretion of significant amounts of protein. The excretion of 0.1 g of glucose per 11 urine causes an increase in specific gravity to 0.004; 0.4 protein to 0.001.

Indices of urinalysis that are deviations from normal are indicative of metabolic disorders

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