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HIV virus causes Acquired Immunodeficiency Syndrome (AIDS). There are two main types of HIV viruses which cause disease in India – HIV-1 and HIV-2. Most cases are due to HIV-1 while HIV-2 is very rare.

Qline Diagnostics does HIV testing in Ahmedabad by various standardized, accurate and reliable methods available.

Various Tests available for HIV testing at Qline Pathology Laboratory are :

1. HIV-1 & 2 antibody – rapid screening test : by rapid immunochromatography/Strip method. Most commonly performed for screening purpose with sensitivity of >99% and is the cheapest available test. Can separately tell presence of HIV-1 or HIV-2 antibody. Positive/Reactive result Is Checked By 3 Methods As Per NACO.  Non Reactive result implies that antibody to HIV 1 / 2 have not been detected in the sample. This means the patient has either not been exposed to HIV 1 / 2 infection or the sample has been tested during the “window period“ i.e. before the development of detectable levels of antibodies. Hence a Non Reactive result does not exclude the possibility of exposure or infection with HIV 1 / 2.
2. HIV-Duo test / HIV by CMIA/ELISA – 4th Generation : p24 antigen and antibody to HIV-1 & 2 – All detected combined and not separate. Screening Test For HIV Infection. Positive Is Checked By 3 Methods As Per NACO
3. p24 antigen test (screening) : For early detection of HIV-1, detects only p24 antigen, can come positive as early as 15 days if a person is infected as compared to antibody tests which takes longer time.
4. HIV-1 Proviral DNA (Qualitative) : For early detection of HIV-1. Molecular test done by real time PCR. Qualitative test means it will tell positive or negative and not count. Cost Rs 3600
5. HIV-1 RNA detection (Qualitative) : HIV-1 RNA detection by Cobas Taqman, Molecular test.
6. HIV-1 RNA Quantitative (HIV-1 Viral load by RT-PCR) : by real time PCR (RT-PCR). This test is prescribed by a doctor as an aid in the management of HIV 1 infected patients and is not intended for use in the initial diagnosis or confirmation of HIV 1 infection. This test is used to assess patient prognosis and monitor the effect of anti-retroviral AIDS therapy.
7. HIV-1 RNA Quantitative (HIV-1 Viral load by Cobas Taqman) : molecular test done by Cobas Taqman method, considered to be more sensitive than routine RT-PCR method. So its little costly. Can be done both from blood and CSF.
8. HIV-1 Coreceptor Tropism Genotypic :  by PCR sequencing, Test can be performed only if Viral Load Is >2000 Copies. Done by RT-PCR and sequencing method. The high replication rate of HIV virus along with its rapid mutation rate leads to accumulation of mutations, some of which may reduce susceptibility to hiv drugs. HIV 1 Genotyping identifies mutations in HIV 1 Reverse Transcriptase & Protease genes and thus helps in guiding initiation or change of Anti HIV 1 retroviral therapy. No Genotype / Drug resistance detected if  HIV sequence
   divergence preventing amplification; Absence of HIV infection or Inhibition of PCR.
9. HIV-1 Drug Resistance Panel : Drug Resistance – (PI, NRTI, NNRTI), Drug Resistance-Extended (PI, NRTI, NNRTI, INSTI), Drug Resistance – Integrase Inhibitor Resistance. All the above panels will be done along with viral load by RT-PCR test included. Test can be performed only if Viral Load Is >2000 Copies. Resistance done by DNA sequencing method.
10. HIV-1 Combo test : For therapy monitoring purpose, includes HIV-1 Viral Load and CD45/CD3/CD4/CD8 counts.
11. Western Blot test for HIV 1 & 2 Antibody : Confirmatory test for HIV. Detects antibodies to various antigens (gag/core, pol, envelope, p36) of HIV-1 and HIV-2. Indeterminate results may be seen with early HIV 1/2 infections, Autoimmune diseases, pregnancy and recent Tetanus Toxoid administration
12. HIV-2 Antibody by Western blot : Confirmatory test for HIV-2.
13. HIV-2 RNA detection (Qualitative) : by real time PCR molecular method.
14. HIV-2 viral load (Quantitative) : by real time PCR molecular method.
15. HIV Early Detection Profile : which will include HIV-DUO, P24 Antigen test, HIV 1&2 RNA PCR Qualitative for age >2 years.

Note : False negative or False positive tests can happen due to limitations of the testing method and/or window phase and/or detection limit of the assay. Test results should be interpreted with caution by a physician/clinician along with history and clinical examination findings. Few of the tests are outsourced for the performance of the test. Repeat sample may be required in case of recheck.