Kaposi's disease

Kaposi's sarcoma (KS) is a type of cancer that can form masses in the skin, lymph nodes, or other organs. The skin lesions are usually purple and are most often on the lower limbs. The disease can also affect the digestive tract and the lungs. It is caused by a combination of factors, including infection with Human Herpesvirus 8 (HHV-8), also known as Kaposi's sarcoma-associated herpesvirus (KSHV), and a person's immune system condition. It is more common in people with weakened immune systems, such as those with AIDS, and in people taking immunosuppressive medications.

Etiology and Pathogenesis

Kaposi's sarcoma is associated with infection by HHV-8. This virus is found in the lesions of all patients with Kaposi's sarcoma. Not everyone infected with HHV-8 will develop KS, suggesting that other factors, such as genetic predisposition and immune system deficiencies, also play a role. The disease is particularly prevalent among individuals with HIV/AIDS, indicating a significant link between KS and immune system suppression.

Clinical Presentation

The clinical manifestations of Kaposi's sarcoma vary depending on the stage of the disease. Early lesions may appear as flat or slightly raised spots that are pink, red, or purple. These lesions can grow into larger plaques or nodules. In advanced stages, KS can spread to other parts of the body, including the gastrointestinal tract and lungs, leading to significant complications.

Diagnosis

Diagnosis of Kaposi's sarcoma involves a combination of clinical examination and biopsy of the lesions. Imaging studies may also be conducted to assess the extent of the disease. The presence of HHV-8 in the lesions, detected through molecular techniques, confirms the diagnosis.

Treatment

Treatment options for Kaposi's sarcoma depend on the extent of the disease and the patient's immune status. For localized skin lesions, treatments may include surgery, radiation therapy, or cryotherapy. In cases where the disease is widespread or the patient has a significant immune deficiency, systemic treatments such as chemotherapy or biological therapy may be necessary. Antiretroviral therapy (ART) is also crucial for patients with HIV-associated Kaposi's sarcoma.

Epidemiology

Kaposi's sarcoma has a higher prevalence in certain populations, particularly among men who have sex with men, individuals from certain regions of Africa, and people with compromised immune systems. The incidence of KS has declined significantly in regions where ART for HIV is widely available.

History

Kaposi's sarcoma was first described by Hungarian dermatologist Moritz Kaposi in 1872. Initially, it was considered a rare cancer, primarily affecting elderly men of Mediterranean or Eastern European Jewish descent. The emergence of the AIDS epidemic in the 1980s led to a dramatic increase in the number of KS cases, particularly among men who have sex with men. This association with HIV/AIDS brought renewed attention to the disease and its underlying mechanisms.