Question

John is a longtime patient in the practice where you work. Normally, he comes in once a year for a routine physical, but lately (the last six months) he has been in three times, complaining of extreme fatigue and weight loss (he has lost 15 pounds over the last seven months). The attending physician ordered a standard ELISA-type human immunodeficiency virus (HIV) test, which came back negative. This was in January. He was supposed to come back in May for a repeat test, but he was back one month later with a severe case of genital herpes lesions that had not healed after three weeks. The herpes eventually subsided, and he returned in May for a repeat HIV test. At this time, he told the doctor that he was recovering from a severe respiratory infection that he had been fighting for weeks. After more blood-work, the physician noted that his ELISA HIV results were negative again. His CD4 count was 200 cells/mm3. Two months later John was admitted to the hospital and a lung biopsy showed that he had Pneumocystis carinii; another HIV test was negative. He was released three weeks later, but after two months he was admitted again with the same infection. Another HIV test revealed negative results. Three days later he died.

1. What is an ELISA test, and what does the one for HIV actually detect? 2. John did indeed have an HIV infection, but continued to test negative. What are the possible explanations for the consistently negative results? (hint: it is not seroconversion) 3. Are there any alternative tests available for clinicians to test patients that they suspect are HIV-positive yet who test negative with normal HIV tests? Describe at least two different alternative tests. 4. Would you expect patients with a lack of serum reactivity (few to no antibodies) to have a fast or slow progression from HIV infection to full blown acquired immune deficiency syndrome (AIDS)? Defend your answer. 5. Which of John's reported symptoms are consistent with a diagnosis of HIV?

Answer 1

1)What is ELISA test?

ELISA stand for enzyme linked immunoassay.It comment used to detect antibodies in the blood (An antibody is a protein produced by bodies immune system when it detect harmfull substance called antigens.

It is performed in lab with blood sample ,here the targeted antibody or antigen linked to a specific enzyme if the target substance in the sample the test solution turns to different colour.

2) Negative result may occure due to if the patient has yet not developed antibodies .In early stages patient will develop antibodies this period is called window period.

mistakeby laboratory.

Time and temperature will also affect the result.

Due to insufficient sample.

3)HIV test other than ELISA

a)Rapid HIV test

b)western blot test(used for confirmation for the elisa or rapid HIV rest)

c) indirect flurescent antibody(Used to conform result of an ELISA .

4)Lack of serum reactivity will also cause to progression and aids.Here in initial period some there is no antibodies in blood during test this called window period.But later it will progress.

5)If the person infected with HIV will get fatigue,weight loss,pnumocystis carinii,genital herbs these are the signs and symptoms of HIV,but mostly first the person who is infected with HIV will get fatigue and weight loss.