While some aspects of our health are more visible than others, many become evident through symptoms that we can see from the outside. That’s why organs such as our hair, skin and nails are so useful ...

The telltale itch begins subtly – perhaps a slight irritation on your arm or an uncomfortable warmth spreading across your chest. Before long, your skin erupts in patches of redness, bumps, or scales ...

Enlarging purple pruritic nodules on the dorsal neck One month after a painful neck rash, an HIV-positive man develops pruritic purple lesions at the same site. A 34-year-old African American man ...