Uses: 

1.Diagnosis of pregnancy- May be positive 02 days after missed period. Most useful in early diagnosis.

2.To confirm if the fetus is dead. The test is negative in IUD.

3.Diagnosis of hydatidiform mole and chorionic epithelioma where the test is positive even in diluted urine.

4.Diagnosis of pseudocyesis.

Principle:

The test detects human chorionic gonadotrophin (HCG) in

urine which is elevated in :

Pregnancy.

Hydatidiform mole.

Choriocarcinoma.

Specimen :

First morning urine sample is preferred because this will contain the highest level of HCG.

The specimen must be collected in a container free from all traces of detergent and preservatives.

When the urine is cloudy it should be filtered or centrifuged and the supernatant fluid used.

Immunological or Serological Methods :

These are antigen-antibody reactions. Kits are commercially available.  

Latex agglutination slide test:

Recommended for the qualitative determination of human chorionic gonadotrophin in non-diluted urine.

Monoclonal anti HCG antibodies are bound to latex particles.

Glass slide with 6 test cells, latex reagent, control positive urine & control negative urine, disposable urine pipettes and mixing sticks are supplied with the kits.

The test is to be done within 24 hours.

Both negative and positive controls are to be use each time a test is done.

Agglutination within 2 minutes indicates a positive test.

Immunochromatographic(IC) Pregnancy test:

IC pregnancy tests use a monoclonal antibody dye conjugate and polyclonal solid phase antibodies to detect HCG in urine. The tests have both high sensitivity and specificity.

Occasionally the level of HCG is measured in : Trophoblastic tumour, for this quantitive test is done. 

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