Skin

Question 1

The subtypes of Kaposi sarcoma -

Give the common the pathogenesis.

Give the key DDx

Answer 1

HHV-8 infection (e.g due to imapaired immune function) -> endothelial infection -> endothelial proliferation ->lymphatic differentiation -> increased cytokines/inflammation ->angiogenesis

1)Classic - age 70 Mediterranean men. Indolent. Senes sunt otiosi
2) AIDS related - respond to change in/more effective HIV treatment. Can be aggressive or indolent..
3) Endemic - Equatorial africa, indolent, occaisionally rapid progress
4) Immunosuppressed. Relatively common in this population. Like Classic, prefers distal extremeties. May regress w/change of supression.

DDx: Main is angiosarcoma (which prefers H&N)
Vascular stasis
Haemongioma (e.g spindle cell)
“Kaposiform haemangioendothelialoma HHV8-ve”