How to do Urine Pregnancy Test

Urine Pregnancy Test

(Human chorionic gonodotropin test)

The hCG one step test is used for the qualitative detection of human chorionic gonodotropin in urine.

Principle

Fig. Pregnancy test strips

The hCG one step pregnancy test is a rapid chromatographic immunoassay for the qualitative detection of human chorionic gonodotropin in urine to aid in the early detection of pregnancy. The test device consists of two lines for the result indication, the test line and the control line. The test line consists of combination of antibodies including monoclonal hCG antibody where as the control line consist of goat polyclonal antibodies and colloidal gold particles. When urine specimen is added in the wall of test device the specimen migrates along the membrane to react with the colored reconjugate via capillary action and form the colored line. Presence of colored line indicates positive result where as absence of colored line indicates negative result.

Reagents

The test device consists anti hCG particles and anti hCG coated on membrane.

Dipstick method for Urinalysis (MULTISTIX METHOD)

DIPSTICK METHOD OF URINALYSIS

Multistix reagent strip method

Multistix reagents are clear plastic strips. Seven different reagent areas are affixed on the strip. These different cellulose areas are impregnated with specific testing chemicals according to the test which reacts with specific substances present in urine by changing the color. Color change chart is observed and compared to the color chart for the presence of abnormal levels of substances .Special care in their use is required to prevent inaccurate results and confirmation of quantitative test is appropriate if the results from dipstick testing reveal abnormalities.

The various determinations done by multistix are

pH, Specific Gravity, Glucose, Protein, Ketones, Urobilinogen, Blood, Bilirubin

Fig. Multiple strip for Urinalysis and their interpretaiton

The reagent strips are also available for only one or two tests such as glucose, glucose and protein, glucose and ketones.

Urinalysis : Chemical Examination

Chemical Examination of Urine

The routine analysis of urine includes chemical test for protein, glucose, ketone bodies, occult blood, bile salts, bile pigments and urobilinogen. 

Proteins in urine

Urine normally contains only a scant amount of protein which derives both from blood and urinary tract itself. Mainly albumin is filtered from nephrons due to low molecular weight others are reabsorbed by renal tubules. Other protein includes serum or plasma globulin, mucus or mucin, hemoglobin, bence jones protein.

Determination of protein in urine

Principle

All the methods are based on the principle of precipitation of protein by chemical agents or coagulation by heat.

Urinalysis: Collection, Preservation and Physical Examination

Introduction

Urine is an ultra-filtrate of plasma from which substances essential to the body are reabsorbed and through which those substances not needed are excreted. The nature and amount of substances present in urine reflect ongoing physiological processes in health and disease states.

Routine urine analysis is mainly performed for two purposes: 

• To find out the metabolic and endocrine disturbances of body
• To detect the intrinsic condition that may adversely affect the urinary tract or the kidney.

Collection of urine

For urine analysis fresh early morning sample is preferred because it is most concentrated and acidic which preserves the formed elements well. For the quantitative test and concentration test for tubercle bacilli 24 hour urine specimen is required. For bacteriological test collected urine sample should be free from contamination and it should be collected in sterile container .collection by catheterization into sterile container is the best.