chemical examination of urine 1

ascorbic acid

A reducing agent that can significantly influence the results of urine reagent strips

Blood

Bilirubin

Leukocyte Esterase

Nitrite

Glucose

chemical components of urine that are affected by ascorbic acid

proteins

• are normally present in minute amount in a healthy urine,

• It is known to be the most indicative of renal disease

Less than 10mg/dl/

100mg/dl/24 hours

normal value of proteins in urine

25

— mg of protein in urine appears positive in reagent strip

tamm horsfall protein

also known as uromodulin

• albumin

• tamm horsfall protein

• serum macroglobulin

• Proteins from body fluids such as prostatic fluid, seminal fluid and vaginal secretions

normal proteins in urine

tamm horsfall protein

a glycoprotein, is produced routinely in the ascending loop of Henle; incorporated in filtrate

bence jones proteins

It is an abnormal protein excreted by patients with multiple myeloma.

40-60C

100C

bence jones proteins

• precipitates at — and disappears when urine is heated at —

100°C

40-60°C

bence jones proteins

• Though interference caused by other precipitated

  proteins can be removed by filtering at — and

  observation of turbidity at —

immunoelectrophoresis

serum electrophoresis

bence jones proteins is diagnosed detected by

30 mg/dl or 300 mg/L

There is a clinical proteinuria when protein level measured more than —

prerenal proteinuria

also referred to as overflow proteinuria. It is usually transient and is associated to conditions like septicemia, inflammation, haemolytic episode, muscle injury, multiple myeloma and macroglobulinemia and immunoglobulin paraprotein

acute phase reactants

marker to indicate presence of infection or inflammation

renal proteinuria

It is a type of proteinuria that is associated with protein wasting due to true renal disease or tubular damage

• glomerular

• tubular

• orthostatic

types of renal proteinuria

glomerular proteinuria

occurs when the glomerular filtration has been disrupted.

benign proteinuria

• physiologic

produced by conditions such as strenuous exercise, high fever, dehydration, and exposure to cold

tubular proteinuria

occurs due to impaired tubular reabsorptive capacity. It is caused by toxic substances/heavy metals, severe viral infections and Fanconi’s syndrome.

orthostatic proteinuria

is characterized by urinary protein excretion whenever an individual is in an upright position over an extended period of time

microalbuminuria

albumin levels in the urine are 20 to 200 mg/L

post renal proteinuria

It is the incorporation of protein to urine as it passes through the structures of lower urinary tract. It is attributed to menstrual contamination, vaginal secretion, prostatic fluid and seminal fluid

kidney damage

icteric plasma looking protein indicates

prerenal proteinuria

• increased protein in the systemic circulation

• high plasma protein levels

renal proteinuria

• damaged glomerulus

• no tubular reabsorption

post renal proteinuria

infection/contamination from the reproductive system

glucose

is known as the marker for Diabetes Mellitus / Pancreatic insufficiency

glycosuria

pertains to the appearance of glucose in urine once the renal threshold on plasma glucose that is about 160-180 mg/dl has already been met

glycosuria

appears only when renal threshold is reached — maximal reabsorptive capacity of glucose on PCT

mellituria

presence of other sugar in urine

hyperglycemia-associated glycosuria

may be seen in diabetes mellitus, acromegaly, cushing syndrome, hyperthyroidism, pheochromocytoma, pancreatitis, thyrotoxicosis

hyperglycemia-associated glycosuria

(+) glucose

(+) ketones

renal-associated glycosuria

is associated with tubular reabsorption, end-stage renal disease, cystinosis, fancocini syndrome, pregnancy

renal-associated glycosuria

(+) glucose

(-) ketones

ketones

are intermediate products of fat metabolism that appear in urine when body stored fat is metabolized to supply energy

• aceto-acetic

• acetone

• b-hydroxybutyric acid

3 forms of ketones

aceto-acetic acid

• primarily tested form of ketone

• 20%

acetone

• addition of glycerine to see its presence

• 2%

b-hydroxybutyric acid

• secondary tested form of ketone

• 78%

T

T or F

if aceto-acetic acid is positive, acetone and b-hydroxybutyric acid will also test positive

insulin dosage

ketones are valuable for monitoring

F

T or F

ketones should be present in urine

pathologic presence of ketone

(+) ketone

(+) glucose

physiologic presence of ketone

(+) ketone

(-) glucose

GUT

menstruation

Blood as a parameter does not only mean bleeding and disease in the — , we should also put into consideration that it may also be seen even in physiologic events such as —.

2-5 cells/uL

normal value of blood in urine

>5 cells/uL

clinically significant value of blood in urine

• hematuria

• hemoglobinuria

• myoglobinuria

When blood is tested positive through reagent strips, there are 3 possibilities that may be attributed to it:

hematuria

Pertains to presence of an intact RBC in urine

cloudy red

urine appears as — when there’s hematuria

hemoglobinuria

Can be observed when there is RBC lysis.

clear red

urine appears to be — when there is hemoglobinuria

myoglobinuria

Manifests in urine as clear red sample whenever that there is muscle injury or muscle dissolution

liver damage

Urine bilirubin serves are early indicator of

• pre-hepatic jaundice

• hepatic jaundice

• post-hepatic jaundice

3 types of jaundice

pre-hapatic jaundice

type of jaundice

• too many lysed RBCs and unconjugated bilirubin

hepatic jaundice

type of jaundice

• liver damagw

post-hepatic jaundice

type of jaundice

bile duct obstruction due to crystals formed, bilirubin is not drained; B2 accumulation

porphobilinogen ring

Your bilirubin is a derivative of your

urobilinogen

It is used as a marker for the early detection of HEMOLYTIC DISEASE where in urobilinogen level is greater than 1mg/dL

bile duct obstruction

(+++) urine bilirubin

normal urine urobilinogen

liver damage

(+) / (-) urine bilirubin

(++) urine urobilinogen

hemolytic disease

negative urine bilirubin

(+++) urine urobilinogen

• Reabsorbed back in systemic circulation (20% of urobilinogen)

• Can be reduced to stercobilinogen

• Oxidized into urobilin

3 fates of urobilinogen

stercobilinogen

Urobilinogen when oxidized

stercobilin

Stercobilinogen when oxidized

nitrite

It is a rapid screening test for the presence of nitrate-reducing organisms

cystitis

when reagent strip tests positive for nitrite, it is indicative of

leukocyte esterase

It is the standardized means for the detection of leukocytes present in urine sample. It is used to detect leukocytes so as not to rely on microscopic

esterase

LE test detects the presence of the enzyme —

presence in the granulocytes and monocytes

UTI

(+) LE

(+) nitrite

in acidic urine

(-) LE

(+) nitrite

contamination

in alkaline urine

(+) LE

(+) nitrite

specific gravity

It is known as the density of a solution compared with the density of an equal volume of distilled water at the same temperature

number

density

Specific Gravity

Influenced by the — and — of particles in the specimen

osmolality

Influenced by the NUMBER of particles in the specimen