The Urinalysis data that are usually taken are divided into two; qualitative and quantitative data from urine laboratory tests. As their names indicate, qualitative tests are to evaluate the qualities of urine, such as color, transparency, etc., while quantitative tests try to find the amounts of some indices in urine, such as volume, gravity specifically, the amount of pathological components. Urine (blood, protein, creatinine, etc).

Qualitative data from urine laboratory tests

urine color

� On the first day of the child’s life, the urine is colorless

� On days 2-4 – dark reddish, because large amounts of Urea are excreted.

� In breastfed infants, the urine is nearly colorless until they start drinking fruit juices and eating other foods at 4 to 6 months of age.

� In formula-fed infants, all children and adults, the urine is straw-yellow.

Urine color changes can be physiological. For example;

� Colorless urine is excreted when a person drinks a lot of fluids

� The urine turns orange when the food contains a lot of carotene (carrots);

� Urine will be pink after eating red beets;

� Some medications influence the color of urine. SO, rifampin causes red color of urine, analgin and sulfacilamides-pink, mitroxolinum-saffron-yellow.

Some discoloration of the urine has diagnostic value in kidney disorders:

� Dark brown urine is a pathognomonic symptom of viral hepatitis; the cause of such color is the large number of bile pigments (hyperbilirubinuria); the characteristic sign is the formation of yellowish foam after shaking such urine.

� Smoky-brown urine, resembling tea or cola, is formed in case of damage to the nephrons, when red blood cells pass through the basement membrane of the glomerular capsule and lose hemoglobin. It is the main sign of acute poststreptococcal glomerulonephritis.

� A bright red color can be found when “fresh” red blood cells pass into the urine in case of trauma, kidney tuberculosis, crystals, cystitis, urethritis, kidney tumor.

� Dark violet discoloration is the sign of considerable hemolysis of red blood cells in case of poisoning, Rh conflict, errors during blood transfusion, etc.

Transparency

Urine may be cloudy only in newborn boys for 2-3 days after birth. After that, every healthy person excretes clear urine. Cloudy, dark opalescent urine can be found in case of urinary tract infection, increased amount of crystals, red blood cells or white blood cells, pus or fats in the urine.

Quantitative data from urine laboratory tests

Diuresis means the process of producing urine. The volume of urine (UV per 24 hours) is its laboratory reflection. Their meanings depend on age.

Pathological changes in urine volume

� Polyuria is diagnosed when the volume of urine exceeds normal ranges by 2 times or more. It is the frequent sign of disorders with other systems (decreased cardiac edema, diabetes mellitus, diabetes insipidus). Renal polyutia develops in case of further progress of nephritic edema, chronic renal failure.

� Oliguria means decreased daily urine volume in age ranges and below. Renal oliguria is one of the most significant manifestations of renal failure. There may also be extrarenal causes of oliguria, such as massive profuse bleeding, diarrhea, poisoning, heart failure, shock. It is very important to identify the reason for oliguria because therapeutic plans can be quite different when the urine volume decreases less than 5% of normal data or there is no urine throughout the day. It is one of the most dangerous conditions for a child’s life and needs emergency medical help.

� Anuria can be

1. renal: the kidneys do not form urine due to considerable damage to their tissues.

2. Postrenal (mechanical): Urine is produced but does not reach the bladder due to upper tract or bladder neck obstruction.

In Nocturia, the normal correlation of diurnal and nocturnal urine volume is 2:1. That means that due to increased fluid intake and physical activity, urine excretion is more intense during the day. If the volume of nocturnal urine is greater, it is the manifestation of a diminished renal function.

urine pH

This sign depends on age, eating habits, prescribed drugs, and differs in different people, as well as in a person at different periods.

specific gravity

It is the concentration of electrolytes and other substances dissolved in urine. Decreased specific gravity can be seen in case of drinking lots of fluids, severe renal insufficiency, further progress of edema, diabetes insipidus. The increase is observed in Oliguria, diabetes mellitus, excretion of a marked amount of protein. The excretion of 0.1 g of glucose per 11 of urine causes an increase in specific gravity by 0.004; 0.4 protein-about 0.001.

Urinalysis indices that are deviations from normal are indications of metabolic disorders.