Med USA News

Take care of your health

Diagnosis of HIV Infection

Why is it important laboratory research?

The course of HIV infection is characterized by the long absence of significant specific symptoms. The acute phase begins 3-6 weeks after infection lasts for 1-2 weeks due to non-specific symptoms, usually taken as the usual SARS. During this period, the patient may be concerned about fever, swollen lymph nodes, headache, pain in the joints. The acute phase of the disease is replaced by a long asymptomatic period of up to 10 years or more. Clinical signs reappear only in intensive reproduction of the virus and significant damage to the cells of immune system, at which the transition occurs in advanced stages of the disease. The initial symptoms may be swelling of the lymph nodes, lesions of the mucous membranes of the oral cavity, reducing the level of platelets in the blood, molluscum contagiosum, reactivation of herpes infection in the form of herpes sores on the mucous membranes or shingles. With significant reductions in the level of CD4-lymphocytes in the blood (less than 200/mkl) patients begin to bother many infections, and increased risk of tumors patient is diagnosed with AIDS (Acquired Immunodeficiency Syndrome).

Thus, the clinical manifestations of the disease are significant only in the later stages of the disease. Therefore, the diagnosis of HIV infection play a paramount role laboratory methods.

When should I go to be tested?

At risk for infection with HIV are people promiscuous, drug addicts, injecting drug users, homosexuals, medical personnel, and persons who sparkled blood products, or been transplanted organs and tissues. It should also be mindful of the possibility of transmission from mother to fetus during pregnancy and while breastfeeding.

The risk of HIV infection in intravenous manipulation is not due to the use of disposable syringes. After the introduction of mandatory HIV testing of organ donors and blood infections in such medical procedures significantly decreased.

If you can relate themselves to be at risk, you should regularly be screened for HIV infection. The survey recommended to go to people who are going to get married or planning to conceive. It is mandatory to have to go through screening all pregnant women after the establishment of pregnancy.

HIV testing if desired, any person applying to the state laboratories, HIV, or to a private commercial-certified laboratory. If desired, the test for HIV can pass anonymously.

What tests should take?

The main methods of laboratory diagnosis of HIV infection include the detection of antibodies to the virus, viral antigens, and virus isolation in cell culture.

The most common and best method of diagnosis is the detection of antibodies to the virus in serum by ELISA. However, be aware that there are antibodies to the virus in the serum of only 4-8 weeks after infection. The first weeks after infection represent "seronegative window period" when HIV antibodies are not detected. Therefore, a negative HIV test result in this period does not mean that the person is not infected and can infect others.

It must be emphasized, one of the obtained results should be performed by a qualified physician. Do not take the responsibility for the diagnosis. Most of the research methods have a high percentage of errors and may give false-positive and false-negative results.

When a doubtful or positive result it is obligatory to consult a doctor, venereal diseases. For more accurate diagnosis can be performed repeated studies, determination of antibodies by immunoblotting, the determination of p24 antigen ELISA and determination of viral RNA by PCR. Feature of PCR is that this method of infection can be detected at an earlier stage already at 1-2 month of the disease.

Control over the course of HIV infection and AIDS

When the diagnosis of "HIV infection" the doctor explains the features of the disease and its course. The patient is asked to register with the territorial center of the prevention and control of AIDS for a free medical check-up, an infectious diseases physician. Approximately every six months is recommended for tests to monitor health status. The methods of monitoring patients with HIV infection include the control of "immune status" with the definition of the number of CD4 positive cells by flow cytometry and analysis of the "viral load" by measuring the concentration of viral RNA method PTSR.

Based on the analysis of the results the doctor will be able to determine the status of the immune system to judge the speed of disease progression and the need for treatment assignment.