Declaration: As with all diagnostic tests, a definitive clinical diagnosis should not be based on the result of a single test, but should only be made by the physician after all clinical and laboratory findings have been evaluated.
SAMPLE COLLECTION AND PREPARATION
TEST PROCEDURE( STRIP / CASSETTE )
INTERPRETATION OF RESULTS( STRIP / CASSETTE )
Catalog No. Product Name
ABT-FT-A2 HCG Urine / Serum Strip
ABT-FT-B2 HCG Urine / Serum Cassette
Accu-Tell ® Rapid hCG Pregnancy Test Cassette is a rapid chromatographic immunoassay for the qualitative detection of human chorionic gonadotropin (hCG) in blood serum or urine, as an aid for the early detection of pregnancy.
SUMMARY
Human chorionic gonadotropin (hCG) is a glycoprotein hormone secreted by the developing placenta shortly after fertilization. In normal pregnancy, hCG is detected in urine and serum soon after conception and levels of 5-50 mIU/ml are seen within one week of implantation (1-4). At the time of the first missed menstrual period, hCG concentration in urine and serum are about 100 mIU/ml (2-5). HCG levels increase rapidly during the first 10 weeks of pregnancy, with peak levels of 100,000-200,000 mIU/ml reached at the end of the first trimester (1-4). The appearance of hCG in the urine and serum soon after conception and its subsequent rise in concentration during early gestational growth, make it an excellent marker for the early detection of pregnancy.
Elevated urine and serum hCG levels comparable to those observed in early pregnancy may also be associated with trophoblastic or non-trophoblastic neoplasm, such as hydatidiform mole, and chorio-carcinoma. (6-7) The possibility of such diseases should therefore be ruled out before a positive hCG result is considered diagnostic for pregnancy. Lower levels of the hCG hormone may be associated with placental insufficiency, threatened spontaneous abortion and ectopic pregnancy.
PRINCIPLE
The Pregnancy Test is a sandwich immunoassay (8-9). The plastic card supports a membrane which has been coated with reagents necessary to detect the presence of hCG and provide a positive control so the user can determine if the test result is valid. The sample is applied to the card and reacts initially with the specific, anti-bhCG monoclonal antibody/colloidal gold conjugate on the test membrane. This mixture moves along the membrane, by capillary action, and reacts with a specific anti-hCG in the test region. If hCG is present in the sample, the result is the formation of a colored band in the test region. If there is no hCG in the sample, the area will remain white. The sample continues to flow to the control region and forms a pink to purple color, indicating the test is working and the result is valid.
SAMPLE COLLECTION AND PREPARATION
URINE: Collect specimen in a clean, dry glass or plastic container. Urine specimens can be collected at any time of the day. It is not necessary to obtain a first morning specimen, however concentrations of hCG may be higher in this specimen. The sample can be refrigerated up to 72 hours prior to testing. A refrigerated sample must be allowed to warm to room temperature and mixed before testing.
SERUM: Prepare serum from a whole blood sample which has been obtained using proper venipuncture technique. Store serum at 2°-8° C and assay within 24 hours. If the sample cannot be tested within 24 hours, freeze at -20° C for no longer than 2 weeks. Frozen samples should be mixed thoroughly after thawing and allowed to reach room temperature before testing.
Particulate matter should be allowed to settle prior to sampling urine and serum.
TEST PROCEDURE
Read the entire procedure carefully prior to performing any tests. Allow test strip and urine or serum samples to equilibrate to room temperature (18-30℃) prior to testing.
1. Remove test strip from the sealed foil pouch.
2. Dip the test strip into the sample with the arrows pointing toward the specimen.
3. The sample level should reach the maximum line marked on the strip, but must not exceed the maximum line.
4. Hold the strip in the sample until a reddish color appears at the lower edge of the test membrane (approximately 10 seconds).
5. Withdraw the strip and place it face up on a clean, dry surface.
6. Read the result between 3 and 10 minutes after adding the sample.
INTERPRETATION OF RESULTS
NEGATIVE Only a single red line appears in the control region ( C ). No apparent red of pink line appears in the test region ( T ).
POSITIVE Two distinct red lines will appear, one in the test region ( T ) and another in the control region ( C ).
INVALID The lines in both regions fall to appear, as means improper testing procedures or deterioration of reagents probably have occurred.
NOTES:
The shade of red color in the test line region will vary depending on the concentration of hCG present. However, neither the quantitative value nor the rate of increase in hCG can be determined by this qualitative test.
CASSETTE
TEST PROCEDURE
Read the entire procedure carefully prior to performing any tests. Allow test cassette and urine or serum samples to equilibrate to room temperature (18 – 30℃) prior to testing.
1. Remove test card from the sealed foil pouch. Place the test card on a flat dry surface.
2. Using the provided plastic dropper, dispense 100μl sample (3 drops) to the sample well of the test card. Start timing.
3. Read result between 3 to 10 minutes after adding the sample.
INTERPRETATION OF RESULTS
NEGATIVE Only a single red line appears in the control region ( C ). No apparent red of pink line appears in the test region ( T ).
POSITIVE Two distinct red lines will appear, one in the test region ( T ) and another in the control region ( C ).
INVALID The lines in both regions fall to appear, as means improper testing procedures or deterioration of reagents probably have occurred.
NOTES:
The shade of red color in the test line region will vary depending on the concentration of hCG present. However, neither the quantitative value nor the rate of increase in hCG can be determined by this qualitative test.
QUALITY CONTROL
SERUM: It is recommended that a positive serum control, with a level between 10-20 mIU/ml hCG and a negative serum control, 0 mIU/ml hCG, be used with this test.
URINE: It is recommended that a positive urine control, with a level between 25-150 mIU/ml hCG and a negative urine control, 0 mIU/ml hCG, be used.
A procedural control is incorporated into the test device to indicate the volume of sample is sufficient and that it has been added to the correct well, and that the flow of sample is complete and the colloidal gold has dissolved.
LIMITATIONS
1. A number of conditions, other than pregnancy, including trophoblastic disease and certain non-trophoblastic neoplasm cause elevated levels of hCG. These conditions should be considered with appropriate clinical evidence.
2. A dilute urine specimen may not contain sufficient levels of hCG to give a positive result. If pregnancy is still suspected, a first morning urine should be obtained from the patient 24-48 hours later and retested.
3. As with all diagnostic tests, a definitive clinical diagnosis should not be based on the result of a single test, but should only be made by the physician after all clinical and laboratory findings have been evaluated.
EXPECTED VALUES
Results of tests on healthy, non-pregnant women are negative using the Pregnancy Test. Most pregnant patients have urine and serum hCG levels of 100 mIU/ml or greater the day of the first missed menstrual period. This level of hCG is clearly detected using this test. Peak hCG levels are reached about 8 weeks later. Following delivery, hCG levels rapidly decrease and usually return to non pregnant levels within days. Elevated hCG has also been seen in patients with chorio-carcinoma and non trophoblastic neoplasm. (6,7)
PERFORMANCE CHARACTERISTICS
Sensitivity: The Pregnancy Test detects urine hCG concentrations of 25 mIU/ml. A total of 180 tests were performed, at the three hCG concentrations. hCG specimens were prepared at the following concentrations using hCG free urine; 0 mIU/ml,25 mIU/ml and 600,000 mIU/ml. All tests were negative with the hCG negative urine and positive with the 25 mIU/ml and 600,000 mIU/ml samples.
Hook Effect: There was no hook effect at hCG levels up to 600,000 mIU/ml in urine or serum.
Accuracy: URINE: Urine samples from normal women (n=61) and pregnant women (n=66) were tested with the Pregnancy Test and the reference laboratory test. A 100% correlation was observed between the two tests. No false positive or false negative results were obtained. The accuracy of the test was >99% in urine.
Serum: Serum samples containing no detectable hCG (n=70) and hCG positive serum (n=154) were tested with the Pregnancy Test and the reference laboratory test. A 99.6% correlation was observed between the two tests. No false positive or false negative results were obtained. The accuracy of the test was >99% in serum.
Specificity: The specificity of the Pregnancy Test was determined from cross reaction studies with known amounts of Luteinizing Hormone (hLH), Follicle Stimulating Hormone (hFSH), and Thyroid Stimulating Hormone (hTSH). Samples containing 300 mIU/ml hLH, 1000 mIU/ml hFSH and 1000 mIU/ml hTSH all gave negative results.
The sensitivity of the Pregnancy Test was established using urine standards calibrated to the WHO 3rd IS 75/537 and the WHO 1st IRP 75/537 respectively.
INTERFERENCE TESTING
Potentially interfering substances were added to hCG free and 25 mIU/ml hCG spiked urine samples. No interference was found with any of the substances at the following concentrations:
Acetaminophen 20 mg/dl Acetylsalicylic Acid 20 mg/dl Ascorbic Acid 20 mg/dl Atropine 20 mg/dl Caffeine 20 mg/dl Gentisic Acid 20 mg/dl Glucose 2 g/dl Hemoglobin 1 mg/dl
Potentially interfering substances were added to hCG free serum and 10 mIU/ml hCG spiked serum samples. No interference was found with any of the substances at the following concentrations: Bilirubin 10 mg/dl Cholesterol 790 mg/dl Hemoglobin 250 mg/dl Triglyceride 1270 mg/dl
STORAGE AND STABILITY
Store as packaged in the sealed pouch at room temperature ( 2– 30 ℃). The kit is stable within the expiration date. The kit should be kept away from direct sunlight, moisture and heat.
FAQ
The above information is just for reference. The actual technical specifications are subject to the insert provided with the product.
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