Kaposi sarcoma is caused by –
**Core Concept**
Kaposi sarcoma is a type of cancer that affects the skin and mucous membranes, characterized by the proliferation of abnormal blood vessels. It is a significant clinical manifestation of acquired immunodeficiency syndrome (AIDS) and is prevalent in individuals with compromised immune systems.
**Why the Correct Answer is Right**
Human herpesvirus 8 (HHV-8), also known as Kaposi's sarcoma-associated herpesvirus (KSHV), is a member of the herpesvirus family and is strongly associated with the development of Kaposi sarcoma. The virus is thought to infect endothelial cells and induce the formation of abnormal blood vessels, leading to the characteristic lesions of Kaposi sarcoma. The exact mechanism of HHV-8-induced carcinogenesis is not fully understood, but it is believed to involve the disruption of normal cellular pathways and the promotion of angiogenesis.
**Why Each Wrong Option is Incorrect**
**Option A:** Human herpesvirus-2 (HHV-2) is primarily associated with the development of genital herpes, a sexually transmitted infection characterized by painful skin lesions and systemic symptoms. It is not linked to Kaposi sarcoma.
**Option B:** Human herpesvirus-4 (HHV-4), also known as Epstein-Barr virus (EBV), is a common virus that infects over 90% of the global population and is associated with several diseases, including infectious mononucleosis, Burkitt lymphoma, and nasopharyngeal carcinoma. However, it is not the causative agent of Kaposi sarcoma.
**Option C:** Human herpesvirus-6 (HHV-6) is a member of the herpesvirus family and is primarily associated with roseola infantum, a common childhood illness characterized by fever and rash. It is not linked to Kaposi sarcoma.
**Clinical Pearl / High-Yield Fact**
HHV-8 is a highly oncogenic virus that is transmitted through bodily fluids and is prevalent in certain geographic regions, including parts of Africa and the Mediterranean. Awareness of this virus and its association with Kaposi sarcoma is essential for clinicians working with immunocompromised patients.
**✓ Correct Answer: D. Human herpes virus-8**