“Urine may be a waste material for man but is an
important guide for a physician”
PRESENTOR: Dr. Anshul Varshney
MODERATOR: Dr. GK Mukhiya
should be analysed as rapidly as possible.
within 30 minutes.
◦ it should be refrigerated immediately and stored for preferably no more than 6–12 hours
◦ Refrigerated urine should be brought to room temperature and thoroughly mixed before
◦ Urine should not be frozen if sediment analysis is to be performed.
Casts are particularly vulnerable to
disintegration and will only be detected if fresh urine is
examined very soon after collection.
C. Microscopic Tests
B. Biochemical Examination
3. Ketone bodies.
4. Bile salts.
5. Bile Pigments.
A. Physical Examination
4. Reaction (pH).
5. Specif ic gravity.
COLLECTION OF URINE SPECIMENS
morning sample –concentrated urine --biochemical analysis, casts and crystals.
specimen - chemical screening,
sample urine sample - quantitative estimation
of proteins, sugars, electrolytes, and hormones
stream urine specimen
Normal -- 1.2-2 L /day.
The day is 3-4 times > night.
Night is < 400 ml.
Polyuria >3000ml / day.
Oliguria <400ml / day.
Anuria <100 ml per day.
Normal - amber yellow (due to the presence
of urobilin, uroerythrin and urochromes ).
Colorless - Very dilute urine (Diabetes,
Yellow orange (high colored) - Concentrated
urine, Excess urobilin, Bile pigments, Intake of
smoky - RBC, Myoglobin, Beetroot , Aniline dyes, Menstrual contamination.
Cloudy - Phosphates & Carbonates, Urates & Uric acid, Pus cells, Bacteria,
Milky - Pyuria, Fat, Chyluria.
black – Methemoglobin, Homogenestic acid
( alkaptonuria ),Melanin.
Bile pigments, Drugs like
Rifampicin- orange red
Nitrofurantoin-dark yellow to brown
Levodopa -brown to black;
Amitryptyline- green or blue-green.
Imipenem–cilastatin -brown urine
voided: Clear and transparent
cells : form white precipitate
growth : gives uniform cloudiness.
: it forms bulky deposits
cells : gives turbid smoky urine
: gives turbid milky urine
ODOUR OF URINE
Fresh urine has aromatic odor
a. Ammonia smell: after prolonged standing
b. Fecal smell: due to urinary infection.
c. Fruity smell: ketosis
d. Mousy order : phenylketonuria.
e. Rancid : Tyrosinaemia.
f. Maple syrup odour : MSUD
pH for urine ranges from 4.5 – 8.0.
pH < 7 indicates acid urine and a pH > 7 alkaline urine.
foods (such as citrus fruits and dairy products) and
medications (such as antacids) can affect urine pH.
a diet high in protein the urine is more acidic, while a
diet high in vegetable material yields a urine that is more
CAUSES OF ACIDIC URINE
CAUSES OF ALKALINE
with urease producing org
retention due to obstruction
specific gravity (SG) of urine is a useful
indicator of renal concentrating ability.
This can be readily obtained by measuring the
refractive index (RI) in specially calibrated
specific gravity of a solution refers to the ratio of its
weight to that of an equal volume of water at the same
urine, the specific gravity is a function of the number
and weight of the dissolved solute particles.
gravity measures the concentrating and diluting
abilities of the kidney.
always has SG greater than that of distilled water,
which has an SG of 1.000.
adults with adequate fluid intake: 1.016 and 1.022 (in
a 24 hours specimen).
SG of urine is increased by large amounts of glucose,
protein, lipid and contrast material.
LOW SPECIFIC GRAVITY
HYPOSTHENURIA :indicates dilute urine,
which may be caused by:
- Diabetes insipidus ( can be as low as 1.001).
- Drinking excessive amounts of liquid.
- Pyelonephritis, glomerulonephritis.
- Use of diuretics.
HIGH SPECIFIC GRAVITY
HYPERSTHENURIA : indicates very
concentrated urine, which may be caused by:
- Diabetes mellitus.
- Adrenal insufficiency.
- Toximea of pregnancy (protein in the urine).
is little or no variability between several
specimens from a patient , and SG is fixed at
indicates : severe renal damage in which there
is disruption of both concentrating and diluting
1.Refractometer (total solids meter ): It measures the ratio
of the velocity of light in air to the velocity of light in urine.
2. Urinometer : is a weighted float marked with a scale for
specific gravities from 1.000 to 1.060. The urinometer is
simple and quick to use.
3. Multiple test dipstick : an indicator changes color in
relation to ionic concentration.
normal circumstances glucose in not excreted in urine.
is freely filtered then reabsorbed in the proximal tubule, but resorptive
capacity is limited.
occurs when : blood glucose exceeds this renal threshold, for example
in the absence of hyperglycaemia reflects:
- a tubular resorption defect eg: Fanconi syndrome
Ketonuria is usually associated with diabetic ketoacidosis
detect acetoacetate and to a lesser extent,
acetone but do not detect betahydroxybutyrate (BHB).
are excreted when the body metabolizes fats
BILE IN URINE
constituents are :
1. Bilirubin (bile pigments),
2. Bile salts,
3. Urobilin and Urobilinogen.
Bilirubin appears IN JAUNDICE.
Increased bilirubinuria may be caused by liver
diseses, cholestasis or haemolytic anaemia.
Bilirubin in urine is in the form of conjugated
BLOOD IN URINE
blood cells or Haemoglobin in urine.
hemolysis occurs in circulation or urine.
an occasional red cell may be found on
microscopic examination of the urine sediment.
women during menstruation, the urine may get
contaminated with menstrual blood
the presence of red
blood cells in urine.
- Renal disorders, Infections
or Neoplasm or Trauma related to any part of
the presence of blood
pigments in the urine without the presence of red
- Hemolytic anemia, Transfusion reactions, Malaria,
Paroxysmal Nocturnal Hemoglobinuria.
this test, urine is spun in a centrifuge so the solid materials
(sediment) settle out. The sediment is spread on a slide and
examined under a microscope.
of materials that may be found include:
◦ Red blood cells
◦ White blood cells
◦ Epithelial cells
types of cells can be found in the urine, some of
which come from the blood and others from the different
types of epithelium that line the urinary tract.
4. Uroepithelial cells
5. Squamous cells
is the presence of abnormal numbers of red
blood cells in urine
to glomerular damage, kidney trauma, urinary tract
stones, urinary tract infections, blood toxins, and physical
from the vagina in menstruating women.
RBC may be present even in healthy individuals.
HAEMATURIA CAN BE
: 80 % of the erythrocytes show
a regular (or isomorphic) appearance.
: when a similar proportion of
erythrocytes are changed (or dysmorphic).
: when the two types of cells are
approximately in the same proportion.
Isomorphic erythrocytes (dark cells have lost
their hemoglobin content)
refers to the presence
of abnormal numbers of WBC
that may appear with infection
in the urinary tract.
from the vagina, especially in the presence of
vaginal and cervical infections, or the urethra in
men and women may contaminate the urine.
Appear as cells with an average
diameter of about 10 μm
and a granular cytoplasm
surrounding a lobulated
in UTI , active proliferative glomerulonephritis, acute
or chronic interstitial nephritis, and urological disorders.
women, consequence of urine contamination from genital
such cases, they are associated with large
amounts of squamous epithelial cells and bacteria.
Chronic inflmmatory conditions ,
viral diseases, renal transplant rejection
gradual or abrupt appearance of
lymphocyturia in renal graft recipients is an
early and sensitive marker of acute cellular
RENAL TUBULAR CELLS
to ovoid mononucleated cells,
13um. Few tubular cells are rectangular,
polygonal or even columnar.
cells are a found in:
- acute tubular necrosis
- acute interstitial nephritis
- acute cellular allograft rejection and
- acute nephritic or nephrotic syndrome.
come from the urothelium, a multilayered
epithelium lining the urinary excretory tract from
the calyces to the bladder in the female and to the
proximal urethra in the male.
main types of urothelial cells are found.
Deriving from the deep layers :
have club-like or ovoid
appearance, a thin cytoplasm,
and a mean diameter of about
found in urolithiasis, bladder
ureteric stents or prolonged
Deriving from the superficial
round to oval and are
much larger having a mean
diameter of about 30 μm.
abundant cytoplasm with few granules
and a small, central nucleus.
are the largest cells found in the urine,
with a mean diameter of about 55 μm.
are found routinely in small numbers,
being exfoliated from the urethra.
found in large numbers, they indicate a
contamination of urine from vaginal discharge.
are present in urine mainly as droplets.
can be either isolated or in aggregates —or within casts and cells.
casts or cells, they can form 'oval fat bodies', which are tubular cells or
macrophages gorged with lipids.
polarized light: when containing free cholesterol and cholesterol
esters, they appear as 'Maltese crosses', which are bright particles cut by
syndrome or heavy proteinuria.
or with non-glomerular diseases.
primary abnormalities of lipid metabolism, such as Fabry's disease.
(a) A large aggregate of lipid droplets.
(b) A macrophage partly gorged with lipid droplets (a so-called 'oval fat body').
(c) Maltese crosses
are elongated elements with a basic
cylindrical shape that has some possible
variation due to bending, wrinkling, and
is the sole site of origin.
glycoprotein secreted by thick part of ascending loop of henle
and early distal convoluted tubules.
1/3 of total urinary protein.
the matrix of all casts.
protein forms a meshwork of fibrils that can trap any
elements present in the tubular filtrate including cells, cell
fragments or granular material.
frequently observed casts.
almost entirely of Tamm-Horsfall
refractive index so not easily
visualized with brightfield microscopy.
Easily visualized with phase contrast
be found normally and also seen in:
chronic renal diseases some casts
become denser in appearance and
known as waxy casts.
refractive index so easily
visualized with brightfield
associated with tubular
inflammation and degeneration.
and chronic renal allogratft rejection.
unusually broad waxy casts are found known
as renal failure casts.
- They imply advanced tubular atrophy and/or
dilatation , in turn reflecting ESRD and extreme stasis
of urine flow.
are hyaline casts
amounts of fine
are the most
frequent casts seen in
casts can contain either
fine or coarse granules.
from plasma protein
aggregates that pass into
tubules from damaged
from cellular remnants of
WBC, RBC, damaged renal
and tubular diseases.
infection, chronic lead
granular casts occur with Haematuria in
renal papillary necrosis.
material is incorporated
into the cast matrix from lipidladen renal tubular cells.
seen with heavy
proteinuria, so feature of
Casts containing urates, calcium oxalates and
Indicate deposition of crystals in the tubule or
Hematuria related to tubular damage
accompanies crystal casts.
CASTS- red brown in colour and occur with
myoglobinuria following acute muscle damage. May be
associated with acute renal failure.
CASTS- seen in obstructive jaundice as deep
yellow brown colored.
phenazopyridine cause a bright yellow to orange
colour in acid urine and will color casts and cells.
yellow to red or even
seen with erythrocyte
casts and glomerular disease.
seen with tubular bleeding
embedded in the matrix of cast
undergo degenerative processes
haemoglobin casts are formed.
An erythrocyte cast.
Inset: a haemoglobin cast
1. ERYTHROCYTE (RBC) CASTS
contain variable amounts of erythrocytes
embedded in the matrix of the cast.
Indicator of bleeding with in nephron.
considered as a highly specific marker of
Glomerular damage allows rbc to escape
into tubule and if there is concomittant
proteinuria and optimal conditions for
cast formation , rbc casts form in distal
LEUCOCYTE (WBC) CASTS
variable amounts of neutrophils and
indicate the renal origin of leucocytes.
in patients with urinary tract infection, since
their presence suggests the involvement of the
also be found in acute interstitial nephritis
and proliferative active glomerulonephritis.
contain tubular epithelial cells.
in all conditions associated with
tubular damage such as:
acute tubular necrosis.
acute interstitial nephritis.
renal allograft cellular rejection.
metal poisoning, ethylene glycol,
by precipitation of urinary salts when
alteration in multiple factors affect their solubility like
pH, temperature, concentration.
can contain several types of crystals.
are found in both acidic urine and alkaline urine.
are birefringent under polarized light.
crystals precipitate at a pH <5.4.
Wide range of shapes.
Appear mostly as lozenges which have a typical amber
polarized light show polychromatic birefringence.
1.Reflect increased nucleoprotein turnover eg
chemotherapy for leukemia
2.Evidence of uric acid stones lodged in ureter.
3.Urate nephropathy of gout.
main types of calcium oxalate crystals:
Monohydrated: dumb-bell or as biconcave/biconvex
discs , birefringent.
Bihydrated: bipyramidal shape.
can cause extensive tubular injury
absorption of oxalates from food following
small bowel resection, crohns disease.
thin, hexagonal, birefringent plates with
be isolated, heaped upon one another, or
mostly in acidic urine.
Also found in cystine calculi.
CRYSTALS DUE TO DRUGS
transparent thin plates, with
sharp edges and corners.
with other lipid
particles, in the urine of
patients with nephrotic
syndrome or heavy
A plate of cholesterol crystal (on its
lowest corner, a few small lipid droplets;
on the background, a hyaline cast)
as rods or cocci.
be found due to contamination rather
presence of leucocytes increases the
probability of a real infection, especially in
women, but leucocytes and bacteria may
contaminate urine from genitalia.
patients with acute pyelonephritis,
bacterial casts can be seen.
Candida - most frequently found yeast
Elongated, ovoid, or spherical.
Presence of buds.
Most frequent cause is contamination from
Grows in the urinary tract, mostly in
patients with diabetes, structural
abnormalities, indwelling catheters,
prolonged antibiotic treatment or
Candidal casts are found in urine of
patients with renal candidiasis.
adult form lives and lays the eggs in the vesical
plexus and veins draining the ureters.
in Nile valley, West Africa, Arabia.
haematuria, chronic renal failure due to
obstructive uropathy, glomerulonephritis, or bladder
: spindle shaped, a rounded anterior and a conical
posterior end tapering into a delicate terminal spine.