Dermatology (from Greek derma, “skin”) is a branch of medicine dealing with the skin and its appendages (hair, nails, sweat glands etc). A medical doctor who specializes in dermatology is a dermatologist. The surgical practice of dermatology is dermasurgery.
Scope of the field

Dermatologists are physicians (medical doctors) specializing in the diagnosis and treatment of diseases and tumors of the skin and its appendages. There are medical and surgical sides to the specialty. Dermasurgeons practice skin cancer surgery (including Mohs’ micrographic surgery), laser surgery, photodynamic therapy (PDT) and cosmetic procedures using botulinum toxin (’Botox’), soft tissue fillers, sclerotherapy and liposuction. Dermatopathologists interpret tissue under the microscope (histopathology). Pediatric dermatologists specialize in the diagnoses and treatment of skin disease in children. Immunodermatologists specialize in the diagnosis and management of skin diseases driven by an altered immune system including blistering (bullous) diseases like pemphigus. In addition, there are a wide range of congenital syndromes managed by dermatologists.

North American training program: A minimum of 12 years of college and post graduate training is requried to become a dermatologist in the United States and Canada. This includes graduation from a 4-year college, a 4-year medical school followed by a year of post graduate training in medicine, surgery or pediatrics (called an internship) after which a physician may apply for admission to graduate dermatology residency training. Dermatology residencies are among the most competitive in terms of admission criteria. Following the successful completion of formal residency training in dermatology (3 years) the physician is qualified to take certifying board examinations (written and oral) by the American Board of Dermatology. Once board certified, dermatologists become Diplomates of the American Board of Dermatology. They are then eligible to apply for fellowship status in the American Academy of Dermatology. Some dermatologists undertake advanced subspecialty training in programs known as fellowships after completion of their residency training. These fellowships are either one or two years in duration. Fellowships in dermatology include: pediatric dermatology, surgical dermatology including MOHS micrographic surgery, dermatopathology (pathology of skin diseases) and dermatological immunology.

Australian training programme: An Australian specialist dermatologist will have completed 4-6 years of medical school, one internship year and at least one year of general medical or surgical service in the public hospital system, prior to becoming eligibile for specialist training in dermatology. The selection process is rigorous and transparent; candidates must pass science and pharmacology exams and engage in monitored and assessed practical training in medical and surgical dermatology. At the completion of the 5 year training programme, trainees sit a national written examination held over two days. Successful candidates may then proceed to the practical viva examination (held over 2 days) after which they may apply for fellowship status with the Australasian College of Dermatologists.

Indian training in dermatology: To be a dermatologist in India requires a minimum of 3 years after graduation and internship. The period involves rigorous training in all aspects of general dermatology, cosmetic dermatology, venereal diseases (including HIV ) and leprosy. At the end of the training period the resident has to go through written tests and clinical exams. The degree awarded is MD (dermatology, venereology and leprosy). Most specialists also go for certification by the national board (for the award of ‘diplomate of national board’).

The skin is the largest organ of the body and obviously the most visible. Although many skin diseases are isolated, some are manestations of internal disease. Hence, a dermatologist is schooled in surgery, rheumatology (many rheumatic diseases can feature skin symptoms and signs), immunology, neurology (the “neurocuteaneous syndromes”, such as neurofibromatosis and tuberous sclerosis), infectious diseases and endocrinology. The study of genetics is also becoming increasingly important.

Venereology, the subspecialty that diagnoses and treats sexually transmitted diseases, and phlebology, the specialty that deals with problems of the superficial venous system, are both part of a dermatologist’s expertise.

Cosmetic dermatology has long been an important part of the field, and dermatologists have been the primary innovators in this area. In the 1900’s dermatologists employed dermabrasion to improve acne scarring and fat microtransfer was used to fill in cutaneous defects. More recently, dermatologists have been the driving force behind the development and safe and effective employment of lasers, new dermal filling agents (collagen and hyaluronic acid), botulinum toxin (”Botox”), nonablative laser rejuvenation procedures, intense pulsed light systems, photodynamic therapy, and chemical peeling.

Therapy

The skin is obviously accessible to topical local therapy. Antibiotic creams can help eliminate infections, while inflammatory skin diseases (such as eczema and psoriasis) often respond to steroid creams or topical anthralin. Dermatologists are innovators of new immune enhancing treatments, like topical imiquimod for superficial cancers and injection immunotherapy for warts as discussed below.

Topical medications treat many dermatological diseases, but dermatologists also use oral medications. Antibiotics and immune suppressants or immune enhanancing agents (injection immunotherapy or topical imiquimod) for dermatological diseases or tumors. Isotretinoin (”Accutane”) is used for severe cystic acne vulgaris and often produces a life-time remission of this disfiguring disease. Isotretinoin prescribing in the U.S. is now controlled by a cumbersome FDA governmental website called iPLEDGE.

Photomedicine involves the use of ultraviolet light, often in combination with oral or topical agents, to treat skin disease (eg. psoriasis or mycosis fungoides).

Surgical intervention by dermasurgeons may be necessary, for example, to treat varicose veins or skin cancer. Varicose veins can be treated with sclerotherapy (injecting an agent that obliterates the vein) or the long-pulsed Nd:YAG laser. Skin cancers can be managed with excision (including Mohs micrographic surgery), cryosurgery, x-ray, or, more recently, with the topical immune enhancing agent, imiquimod (”Aldara”). The American Society for Dermatologic Surgery is the dermatologists’s professional organization representing the dermasurgery side of this specialty. Dermasurgeons are the expert skin surgeons, having spent a significant part of their residency training years learning this subject.

Dermasurgeons are experts in scar management, including laser resurfacing of acne or traumatic scars, the new nonablative laser rejuvenation of depressed scars, or the use of filling agents (eg. hylauronic acid or fat microinjections) for depressed scars.

Research

From the basic science of cutaneous genetics and immunology, to the practical application of new knowledge and technology in the diagnosis and management of skin disease (like psoriasis) and surgical treatment of skin cancer, dermatologists have led the way. The annual meeting of the American Academy of Dermatology is one of the keys for rapid dissemination of new knowledge to the practicing dermatologist and dermasurgeon.