Studies for Pyelonephritis
Laboratory tests enable to prove or detect a kidney infection.
- Nechiporenko’s urine test
- Urine culture
- Kidney ultrasound
- CT scan and MRT
- General urine test
Normally, in the morning portion of urine is found max 0 to 3 leukocytes in men and 0 to 6 in women and children. Leukocyturia kind is needed to be determined. If a person has no symptoms of pyelonephritis and bacteriuria, the reason for leukocyturia may be acute glomerulonephritis, contamination while collecting urine, interstitial nephritis caused by analgesics, bladder swelling, fever.
Main study method for infection diseases in the urinary system. Detection of bacteria in urine (bacteriuria).
The urine in bladder and kidneys in healthy people is sterile. A person not always has an infection disease, when bacteria are found there. For example, when urinating non-pathogenic bacteria get into the urine from unsterile lower urethra but their amount is max 104 per 1 liter of urine (10,000). Other reasons for bacteria presence without infection in urinary tract are long stay of urine unstudied (bacteria multiply) and unhygienic conditions of urine collection (unclean genitals).
Urine culture is a golden standard of diagnostic study of infection in the urinary system. The study is done to indentify the infection and determine its sensitivity to antibiotics.
Urine bacteria test (urine culture) is a highly important study for chronic pyelonephritis. The urine culture test is done to indentify the infection and determine its sensitivity to antibiotics.
The average portion of urine is collected in a sterile jar not touching its inside walls. To avoid bacterial contamination before collection:
woman inserts tampon into her vagina and washes vulva then she spreads labia with fingers. The urine stream must not touch fingers.
man pull foreskin and wash the top of the penis.
Alkaline reaction in urine (high urine pH).
If you eat and mix different food, acidic metabolic products occur. Therefore the normal urine reaction is considered to be acidic.
During stay ammonia occurs in urine and pH becomes more alkaline (therefore before testing urine may be kept for an hour and a half maximally). Remarkably, alkaline reaction lowers urine density values. Besides, leukocytes are quickly destroyed in alkaline urine which makes harder to estimate leukocyturia level.
Urine with much leukocytes and bacteria reacts with alkali due to the bacterial and ammonacal fermentation during inflammation.
Acidic reaction in urine accompanied by sterile leukocyturia (laukocyturia without bacteriuria) is suspicious about renal tuberculosis.
Nechiporenko’s Urine Test
Usually, Nechiporenko’s Urine Test comes along with general urine test. According to it normal analysis values are leukocytes max 2,000 in 1ml, erythrocytes max 1,000 in 1ml, cylinders are absent or present max 20 in 1ml.
Ultrasound is an imaging study method. When pyelonephritis is suspected the imaging study must begin with the ultrasound.
A Chronic Pyelonephritis may have signs in Ultrasound Imagery. These include:
- Kidneys are asymmetric, affected kidney is less;
- Echo density change: thinned out and dense parenchyma;
- Extension and deformation of the pyelocaliceal system;
- In case of urinary tracts obstruction – hydronephrosis, concrements.
Excretory urography is another imaging study method for pyelonephritis. It is used when the ultrasound shows pathology. Excretory urography has advantages over ultrasound. They are urethral visualization, diagnosis of obstructive uropathy, etc.
Symptoms of Chronic Pyelonephritis
- Delay in coming out and low contrast intensity;
- Abnormal shape and shrunken kidney;
- CJ. Hodson’s symptom and lower renal cortical index. Hodson’s symptom refers to lower thickness of renal parenchyma on poles compared to middle part of kidney;
- Deformation and hardening of pyelocaliceal system;
- Abnormal activity of pyelocaliceal system.
Radionuclide imaging methods (isotope renography, technetium renal scanning) enables to indentify acting parenchyma. It is important for diagnosis, identification and prognosis.
CT and MRT
Computed tomography (CT) and magnetic resonance tomography (MRT) are recommended if ultrasound does not tells insufficiently of cancerous tumor is suspected. Computed tomography has large scale of advantages over ultrasound. It shows location and size of an inflammation outside the kidney and weather other organs are affected or gives images of visceral organs of obese patients.