High risk for kidney problems
The old saying “Astitch in time saves nine” holds true for the treatment
of kidney diseases. Chronic kidney disease (CKD) is not curable and if
not treated can lead to end stage kidney disease (ESKD). As discussed
in the previous chapter, a person with CKD can be asymptomatic, i.e.
no symptoms of the disease may be apparent. However if diagnosis of
kidney disease is made early, appropriate medical treatment can be
rendered and progression to ESKD can be delayed or slowed. So
whenever a kidney problem is even suspected, it is advisable to go for
immediate check up and early diagnosis.
Who should get their kidneys checked? Who is at high risk
for developing kidney problems?
Anyone can develop a kidney problem, but the risk is higher in the
presence of :
- Symptoms of kidney disease
- Difficult to control hypertension
- Family history of kidney disease, diabetes and hypertension
- Chronic tobacco consumption, obesity and/or elderly (above 60
- Chronic intake of pain relievers, e.g., nonsteroidal anti-inflammatory
drugs such as ibuprofen, naproxen
- Congenital defect of urinary tract Screening in such high risk individuals helps in early detection and
diagnosis of kidney disease.
Early stages of chronic kidney disease are usually
asymptomatic, laboratory tests are the only way of detection.
12. Save Your Kidneys
How to diagnose kidney problems? What tests are normally
To diagnose different kidney problems the doctor takes a detailed history,
thoroughly examines the person, check the blood pressure and then
advises appropriate tests. Routinely performed and most useful tests
include urine tests, blood tests and radiological tests.
1. Urine Tests
Different urine tests provide useful clues for the diagnosis of various
types of kidney disease.
- It is a simple, inexpensive and very useful diagnostic test.
- Abnormality seen in a routine urinalysis provides important diagnostic
clues but a normal urinalysis does not necessarily rule out underlying
- Presence of protein in urine (proteinuria) is seen in various kidney
diseases. It should never be neglected. Presence of protein in urine
can be the first, the earliest and the only warning sign of chronic
kidney disease (and even of heart disease). For example proteinuria
is the first sign of kidney involvement in diabetes.
- Presence of pus cells in urine may indicate the presence of urinary
tract infection (UTI).
- Presence of protein and red blood cells (RBCs) provides diagnostic
clues for inflammatory kidney disease (i.e. glomerulonephritis).
Microalbuminuria means that a very small amount of protein is present
in urine. This test provides the first and the earliest clue for the diagnosis
of kidney involvement in diabetes. At this stage, the disease may be
potentially reversible with proper and meticulous treatment.
Other urine tests
- 24 hour urine for protein:
In patients with the presence of protein
in urine, this test is necessary to determine the total actual amount of
protein lost in 24 hours. This test is useful to assess the severity of
the disease and also the effect of treatment on the loss of protein.
- Culture and sensitivity test:
This test provides valuable information
about the type of bacteria causing UTI, and the choice of antibiotic
selection for its treatment.It may take 48-72 hours to get the final
results of this test.
- Urine test for acid fast bacilli:
This test is useful to diagnose
tuberculosis of urinary tract.
Routine urinalysis is very important for the early
detection and diagnosis of kidney disease.
2. Blood Tests
Various blood tests are necessary to establish appropriate diagnosis of
different kidney diseases.
- Creatinine and Urea
Blood levels of creatinine and urea reflects the function of the kidneys.
Creatinine and urea are two by- products which are normally removed
from the blood by the kidney. When the kidney function slows down,
the blood levels of creatinine and urea increase. Normal value of serum
creatinine is 0.9 to 1.4 mg/dl and normal value of blood urea nitrogen
(BUN) is 20 to 40 mg/dl. Higher values suggest damage to the kidneys.
Creatinine level is a more reliable guide of kidney function as compared
Healthy kidneys help in the production of red blood cells which contain
hemoglobin. When hemoglobin is low, it is called anemia. Anemia is a
common and important sign of chronic kidney diseases. However anemia
can occur quite frequently in other illnesses. So anemia is not a specific
test for kidney diseases.
- Other blood tests
Different blood tests frequently performed in kidney patients include:
blood sugar, serum albumin, cholesterol, electrolytes (sodium, potassium
and chloride), calcium, phosphorous, bicarbonate, ASO titer,
complement levels etc.
Serum creatinine is a standard blood test used routinely
to screen for and monitor kidney disease.
3. Radiological Tests
- Ultrasound of the kidneys
A kidney ultrasound is a simple, useful, quick and safe (no radiation
exposure) test which provides valuable information such as the size of
kidney and the presence of cysts, stones and tumors. An ultrasound
can also detect blockage to urine flow in the urinary tract. In advanced
stage of CKD or ESKD both kidneys may be found to be small in size.
- X-ray of abdomen
This test is useul for the diagnosis of calcium containg stones in the
urinary system urinary tract.
- Intra venous urography (IVU)
IVU (also known as intra venous pyelography-IVP) is a specialized X-
ray test. In this test, a radio opaque iodine containing dye (fluid which
can be seen on X-ray films) is injected into a vein in the arm. This dye
then passes through the kidney and gets excreted in to the urine. The
urinary tract (kidneys, ureters and bladder) are rendered radio-opaque,
and this allows visualization of the entire urinary tract. A series of X-ray
pictures are taken at specific time intervals which give a comprehensive
view of the anatomy of the urinary system. IVU can reveal problems
such as stone, obstruction, tumor and abnormalities in structure and
function of the kidneys.
The most important screening tests for kidney diseases are the
urinalysis, serum creatinine and ultrasound of kidney.
In cases of advanced CKD, IVU is usually not recommended because
the injected dye can damage the already poorly functioning kidneys. In kidney failure, excretion of dye during test may be inadequate. This test
is also not recommended during pregnancy. Because of availability of
ultrasound and CT scan, this test is used much less frequently nowadays.
4. Other Special Tests
- Voiding cystourethrogram (VCUG)
Voiding cystourethrogram - VCUG (previously known as Micturating
cystourethrogram - MCU) test is most commonly used in the evaluation
of urinary tract infection in children. In this special X - ray test, under
sterile conditions, the bladder is filled with contrast medium via the urinary
catheter. After the bladder is filled, urinary catheter is removed and the
patient is asked to urinate. X -rays taken at intervals during urination
show the outline of the bladder and urethra. This test is helpful to diagnose
backflow of urine into the ureters, and up to the kidneys (known as
vesicoureteric reflux VUR) as well as identifying structural abnormalities
of urinary bladder and urethra.
- Other radiological tests
In special circumstances for the diagnosis of certain kidney diseases,
other tests such as CT scan of kidney and urinary tract, renal doppler,
radionuclear study, renal angiography, antegrade and retrograde
pyelography etc. can be useful.
Kidney biopsy, cystoscopy and urodynamics are special tests which
are necessary for the exact diagnosis of certain kidney problems.
A kidney ultrasound is a simple and safe test used to
assess the size, shape, and location of the kidneys.
Kidney biopsy is an important test useful in the diagnosis of certain
kidney diseases such as glomerulonephritis, certain tubulointerstitial
What is kidney biopsy?
During a kidney biopsy, a small piece of kidney tissue is removed through
a needle and examined under a microscope. Kidney biopsy is performed
to diagnose the exact nature of certain kidney diseases, e.g.
glomerulonephritis and certain tubulointerstitial diseases, etc.
When is kidney biopsy advised?
In certain kidney diseases even a detailed history, physical examination
and routine tests are unable to establish proper diagnosis. In such
patients, a kidney biopsy may provide additional information, which
can establish the correct diagnosis.
How does the kidney biopsy help?
The kidney biopsy establishes specific diagnosis of certain unexplained
kidney diseases, e.g. glomerulonephritis and certain tubulointerstitial
diseases, etc. With this information, the nephrologist is able to plan
effective treatment strategy and guide patients and their family about
the severity and course of the disease.
By which technique is a kidney biopsy performed?
The most common method is via a percutaneous needle biopsy (usually
performed in the radiology suite), in which a hollow needle is passed
through the skin into the kidney. Another rarely used method is open
biopsy which requires surgery (performed in the operating room).
The kidney biopsy is a test performed to establish the diagnosis of certain kidney
diseases, glomerulonephritis certain tubulointerstitial diseases etc.
How is a kidney biopsy performed?
- The patient is admitted in hospital and his consent is obtained.
- Prior to biopsy it is ensured that blood pressure and blood tests on
blood clotting are within normal. Medications used for the prevention
of blood clotting (e.g. aspirin and clopidrogel) is recommended to
be discontinued for at least 1- 2 weeks prior to biopsy.
Are there any risks to kidney biopsy?
- Ultrasound or CT scan is done to know the position of kidneys and
to determine exact biopsy site.
- The patient is asked to lie face down – on his/her stomach with the
abdomen supported by a pillow or towel. The patient is fully awake
during the procedure. In small children the kidney biopsy is done
under general anesthesia, so the child is not awake.
- After proper cleaning of the skin, the biopsy site is numbed with
local anesthesia to minimize discomfort and pain.
- With the use of a hollow biopsy needle, 2 or 3 small thread like
pieces are obtained from the kidney. These specimens are then sent
to the pathologist for histopathology examination.
- After the biopsy, pressure is applied to the biopsy site to prevent
bleeding. The patient is put on complete bed rest for 6-12 hours and
usually discharged the following day.
- The patient is advised to avoid heavy work or exercise for at least
2-4 weeks after the biopsy procedure.
Like any surgical procedure, complications can occur in a few patients
after kidney biopsy. Mild pain or discomfort over the puncture site and
passing of reddish urine once or twice is not uncommon, but it usually
stops on its own. In rare cases where bleeding continues, blood
transfusion may be required. In extreme and very rare circumstances
where by intractable severe bleeding persists emergency removal of
kidney by surgery may become necessary.
Sometimes kidney tissue obtained may not be adequate for diagnosis
(about 1 in 20). Repeat biopsy may be needed in such cases.
The kidney biopsy is usually performed with the use of a
thin hollow needle with the patient in the fully awake state.