Vetlab Supplies FASTest HW Antigen Test Kit Instruction Manual
- June 9, 2024
- Vetlab Supplies
Table of Contents
Vetlab Supplies FASTest HW Antigen Test Kit Instruction Manual
INFORMATION ON THE TEST-KIT
TEST-KIT COMPONENTS
1 test-kit FASTest® HW Antigen contains:
- 2*, 10, 25** or 50**** test cassettes coated with monoclonal antibodies
- 1 dropper bottle A with 1.0 ml, 1.5 ml, 3.0 ml or ****2 dropper bottles A with 3.0 ml buffer diluent
- 2, 10, 25 or 50 disposable plastic pipettes
- 1 instructions for use
STABILITY AND STORAGE
Store at 15–25 °C
Expiry date see label
APPLICATION AND ABBREVIATIONS
For veterinary use only
In vitro diagnosticum
Follow instructions for use precisely
Lot number
Do not use test-kit components from different kits, lot numbers or beyond
stated expiry date.
S – TEST line,
C – CONTROL line,
LF – Lateral flow
LIABILITY
The entire risk due to the performance of this product is assumed by the purchaser. The manufacturer shall not be liable for indirect, special or consequential damages of any kind resulting from the use of this product.
ACCURACY
Sensitivity 98.6 % – Specifi city 99.1 %
(Comparison Method: Knott’s Test)
INTRODUCTION
The dirofi lariosis of the dog, cat, ferret as well as other carnivores, is
caused by the so-called “heart worm”, a nematode of the fi laria family named
Dirofi laria immitis. Infection of humans (dead end host) is possible
(zoonosis).
The filaria manifest especially in lungs and conjunctive tissue, but are
rarely diagnosed.
The transmission happens via infected, haematophagous mosquito species
(Culicidae), releasing infectious D. immitis larvae (stage L3) in the host
blood with the sting. After development of the larva (stage L4) in the
hypodermis of the host (about 8 days post infection), they migrate into the
blood circulation.
The establishment of the adult worms (macrofi laria: up to 1 mm thick, 20–30
cm long) takes place earliest 80 days p. inf., most of all in the pulmonary
artery and in the right heart chamber. The female adult parasite of the
bisexual macrofi laria produce new larvae (stage L1, microfi laria) at fi rst
after 6 (dog) to 7 (cat) months. These are released together with antigens of
the female reproductive tract to the peripheral blood (microfi laraemia) and
are ingested again by mosquitoes at sucking action. In the mosquitoes, the
larva 1 develops into an infectious larva 3.
The degree of disease depends on the quantity of adult worms (“worm burden”),
localization, duration of infection and the host’s immunological reaction.
Concerning the worm burden, dogs and cats differ a lot. In cats, normally
there are less than 5 worms, in dogs more than 30.
First of all, dirofi lariosis is a cardiopulmonary disease beginning without
symptoms. In advanced stage, right-sided heart failure and Cor pulmonale occur
with symptoms like cough, dyspnoea, heart and lung murmurs, oedemas as well as
fast fatigue. Particularly in small dogs, in case of large “worm burden” the
“vena-cava syndrome” (obturation stenosis because of massive worm cluster in
the posterior vena cava and the right atrium of the heart) occurs and thus
leads to intravascular haemolysis, shock, kidney failure and sudden death.
In cats, rather the lungs are affected and the symptoms are not always typical
for heart worms. Nevertheless, only one D. immitis can be lethal.
Due to the rather diffi cult clinical diagnosis and the short and transient
proceeding microfi laraemia, a repeated testing with FASTest® HW Antigen is
recommended.
Being fast and reliable, the FASTest® HW Antigen detects group-specifi c
antigens of the active reproductive tract of the female adult D. immitis worm.
Due to the long incubation time of 6 (dog) and 7 (cat) months p. inf. (after
stay in dirofi lariosis regions), testing with FASTest® HW Antigen should be
carried out earliest 6 and 7 months after stay in dirofi lariosis regions,
respectively.
INFORMATION ON THE SPECIMEN MATERIAL
Approximately 25 µl (1 drop of attached plastic pipette) 15–25 °C warm freshly obtained whole blood (WB, with our without anticoagulant like Heparin or EDTA), plasma (P) or serum (S) are needed. Native blood without any anticoagulant should be avoided due to the potential risk of microclots. Mix the sample material well before use!
Non-cooled (15–25 °C), WB, P and S should be tested within 4 hours! At 2–8 °C,
WB with anticoagulate, P and S can be stored up to 3 days. Serum and / or
plasma samples can be permanently stored at minimum −20 °C.
Keep in mind that the sample material, as well as all used test-kit
components, should have reached room temperature at the time of application.
Endogeneous and exogeneous interfering substances of the sample (e. g.
albumin, fi brinogen, lipids, CRP, heterophilic antibodies, especially type
IgA, as well as viscosity, pH-value and excess EDTA) as well as native blood
can cause interferences (matrix effects) that can infl uence the target
measurement.
These can lead to an impaired LF and / or unspecifi c reactions on S and C.
SPECIMEN PREPARATION
Normally no specimen preparation necessary!
With suspicion of “false negative” and clinical dirofi lariosis symptoms (see
issue 9 / Information for the interpretation), heat treatment of plasma /
serum before testing is recommended to increase the sensitivity of the antigen
detection.
Heat the plasma / serum in a block thermostat up to 103 °C for 10 minutes.
Immediately centrifuge the resulting coagulate for 5 minutes at 16 000×g
(optimum, alternatively 8–12 000×g). The supernatant won hereof can be used as
sample material for the test procedure.
TEST PROCEDURE
- Remove the test cassette from its foil pouch shortly before use. Place it on a fl at surface.
- Take the disposable plastic pipette and express 1 drop (ca. 25 µl) of whole blood, plasma or serum into the round sample window of the test cassette (fi g.1). Hold the pipette vertically!
- Hold the dropper bottle A vertically and express 3 drops of buffer diluent (approx. 100–120 µl) into the sample window of the test cassette (fi g.2).
- Add 1 additional drop of buffer diluent into the sample window if there is no beginning pink-purple LF visible within 2 minutes after adding the buffer diluent.
READING OF THE TEST RESULT
Read the test result 15 minutes
after the three drops of buffer diluent have beed added into the sample
window.
POSITIVE TEST RESULT (fi g.3)
A pink-purple TEST line (S) of any intensity (varying from very weak to
stronly intensive) and a pink-purple CONTROL line (T) appear.
fi g.3 POSITIVE TEST RESULT
NEGATIVE TEST RESULT (fi g.4)
fi g.4 NEGATIVE TEST RESULT
Only a pink-purple CONTROL line (C) appears. This line indicates, irrespective
of its intensity, that the test has been performed properly.
INVALID TEST RESULT
No CONTROL line visible. The test should be repeated using a new test
cassette.
PRECAUTIONS FOR USERS
- The guidelines for working in medical laboratories must be observed. It is recommended to wear disposable gloves and other personal protective equipment (protective clothing, possibly a face mask). Wash and disinfect hands after completing the test.
- Label sample material and associated test cassette to ensure a precise assignment.
- Use a new pipette and a new test cassette for each sample.
- The buffer diluent contains low concentrations of toxic sodium azide as a preservative, therefore avoid skin / eye contact and / or ingestion.
- The sample material must be seen as potentially infectious and disposed of accordingly, together with the used test-kit components.
TEST PRINCIPLE
The FASTest® HW Antigen is based on an immunochromatographic “sandwich principle” detecting specifi c Dirofi laria immitis group antigens of the adult female reproductive organ.
The Dirofi laria immitis antigens of the sample bind to mobile monoclonal anti-Dirofi laria immitis antibodies which are bound to colloidal gold particles. Migrating along the nitrocellulose membrane (“lateral fl ow”, LF), these antigenantibody complexes are captured by immobilised antibodies forming a pink-purple TEST line (S). The intensity or width of the TEST line (S) depends on the concentration of Dirofi laria immitis antigens in the tested sample.
A correct test procedure will be indicated by a second, pinkpurple CONTROL line (C).
The FASTest® HW Antigen shows no cross reactivity to Angiostrongylus vasorum (Internal study at the Institute for Parasitology of the Vetsuisse Faculty, University of Zurich, March 2020)
INFORMATION FOR THE INTERPRETATION
- The interpretation of the test result should always be based on anamnestic and clinical data as well as the therapy and prophylaxis possibilities.
- Any non-described colour or contour variation of S and C (e. g. greyish, shadow-like lines) has to be considered as unspecifi c reaction and therefore as negative test result.
- Positive test results may be observed in as short as 1 minute depending on the severity of the infection.
- Due to anticoagulated whole blood and / or red hemoglobin background of the test membrane caused by hemolysed blood samples, the visibility of S, especially in case of weak positive samples, could be from bad to not visible.
Possible reasons for false positive test results
- Dog with dead adult dirofi laria remains antigen-positive for approx. 3–4 months a second test after 4 months is recommended!
Possible reasons for false negative test results
- Dog or cat with an infection period less than 6 / 7 months
- Very low worm load, especially in cats
- Infection with only male Dirofi laria, infection with nongravid female Dirofi laria (single sex infection)
- Antigen masking by immune complexes (long-term medication with macrocyclic lactone preventives [“slowkill medication”], infl ammation). Recommendation: heat inactivation of plasma / serum (also read issue 4 / Specimen preparation).
Test-kit for the qualitative detection of Dirofi laria immitis specifi c antigens in whole blood, plasma or serum of the dog and cat
Supplied Exclusively To The UK
Veterinary Market By
Vetlab Supplies Ltd
Visit Our Website
www.vetlabsupplies.co.uk
Telephone: 01798 874567
email us: info@vetlabsupplies.co.uk
Manufacturer:
6912 Hörbranz – AUSTRIA
www.megacor.com
References
- MEGACOR Diagnostik GmbH – Veterinary in vitro diagnostics
- Wholesale Vet Supplies & Products for Practices & Labs | Vet Supplies Online UK