It is VERY nice book. Especially for medical students and residents.
You can understand from detail to basic of diseases. With this book, you know how to approach and make your list of differential diagnosis.
I worked for infectious disease patients for a while, and this book was very useful because you can get the general knowledge not only about infectious diseases but also general internal medicine, skin lesions, bone diseases, and so on. I especially recommend the chart of antibiotics(Chart 37). I like this book because we can also get the update etiology of diseases. So nice.