No other field in medicine has such a plethora of diagnoses as dermatology.
Working at the General Hospital Vienna (AKH Vienna) I am familiar with all fields of dermatology including dermatological emergencies. Skin diseases occur in all periods of life. Typical diseases of the infants are eczema, virus infections leading to exanthemas and atopic dermatitis. In adolescence, skin conditions like acne or psoriasis become more frequent; typical skin diseases of the elder population are non-melanoma skin cancer (basal cell carcinoma, squamous cell carcinoma) and herpes zoster (shingles).
Skin diseases, that occur in all periods of life are the aggressive melanoma, cellulitis, urticarial, warts, eczemas with different triggers as well as allergies.
In addition to all these, there is a plenty of unusual dermatoses ("zebra diagnoses") which are often driven by immunological disorders.