INFECTIOUS DISEASE

TURKISH

VIROLOGY - CHAPTER  SEVEN    

PART FOUR

HUMAN IMMUNODEFICIENCY VIRUS AND AIDS

CO-FACTORS

Dr Richard Hunt
Professor
Department of Pathology, Microbiology and Immunology
University of South Carolina School of Medicine

LINKS  TO OTHER HIV AND AIDS SECTIONS ARE AT THE BOTTOM OF THIS PAGE

Co-factors in AIDS--The enigma of Kaposi's sarcoma

Kaposi's sarcoma is often a corollary of HIV-1 infection in gay men (it is ten times more frequent in gay or bisexual men with AIDS than in other types of HIV-infected individuals such as intra-venous drug users or hemophiliacs). Over 20% of HIV-infected gay men suffer from Kaposi's sarcoma (in the absence of chemotherapy) and HIV-positive patients are at 20,000 fold increased risk of Kaposi's sarcoma compared to the general population. Compared to primary immunodeficiencies without HIV infection, Kaposi's sarcoma develops 300 times more often in immunocompromised gay men with AIDS. 

Clinically, most non-AIDS Kaposi's sarcoma is so indolent that many affected individuals die of other unrelated causes. However, the AIDS-associated form is more progressive involving many sites (skin, lymph nodes, lungs, intestine). This form of Kaposi's sarcoma, so typical of the progression of AIDS in gay men, is not found in other populations that are HIV-positive. It has long been suspected, therefore, that Kaposi's is not the direct result of HIV but some co-factor that is activated in the presence of HIV. This now seems to be the case. In 1994, a Kaposi's sarcoma-associated herpes virus (KSHV, now known as human herpes virus-8 (HHV-8)) was identified. It is found in all Kaposi's sarcoma lesions and in all forms of Kaposi's sarcoma. In AIDS patients, antibodies against KSHV are common only in those that have Kaposi's sarcoma or those that will eventually get it (greater than 80% of this population - in fact detection of KSHV in asymptomatic HIV-infected patients strongly predicts subsequent progression to Kaposi's sarcoma). In contrast, blood samples from infected hemophiliacs show no anti-KSHV antibodies.

It is not known why the virus has established itself to a relatively large extent in the American gay population when most herpes viruses are widely disseminated throughout the population as a whole. Clearly, however, KSHV is sexually transmitted. 

 

OTHER SECTIONS ON HIV

PART I HUMAN IMMUNODEFICIENCY VIRUS AND AIDS

PART II HIV AND AIDS, THE DISEASE

PART III COURSE OF THE DISEASE

PART IV PROGRESSION AND COFACTORS

PART V STATISTICS

PART VI  SUBTYPES AND CO-RECEPTORS

PART VII  COMPONENTS AND LIFE CYCLE OF HIV

PART VIII  LATENCY OF HIV

PART IX GENOME OF HIV

PART X  LOSS OF CD4 CELLS

PART XI   POPULATION POLYMORPHISM

APPENDIX I  ANTI-HIV VACCINES

APPENDIX II  DOES HIV CAUSE AIDS?

APPENDIX III  ANTI-HIV CHEMOTHERAPY

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This page last changed on Tuesday, July 12, 2016
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