, "skin"; and -λογία, -logia
) is a branch of medicine
dealing with the skin and its appendages (hair, sweat glands, etc).
The skin is the largest organ of the body and is the most visible. Although many skin diseases are isolated, some are manifestations of internal disease. Hence, a dermatologist is schooled in aspects of 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 and phlebology
, the subspecialty that diagnoses and treats sexually transmitted diseases
, and phlebology
, the specialty that deals with problems of the superficial venous system
, are in some countries 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. Dermatologists specializing in cosmetic dermatology typically use non-invasive procedures to reverse the signs of aging. Botox has been used since it was FDA approved for the treatment of wrinkles. It is used to minimize wrinkles such as frown lines and crow's feet. Fillers are used to "fill in" lines on the face and to minimize the appearance of wrinkles. Brand names of fillers include Restylane, Perlane, Juvederm, Radiesse and Cosmoplast among many others. Dermatologists are also the pioneers of energy based treatments for the skin and these include lasers, intense pulsed light, radiofrequency, infrared light and photodynamic treatments.
Dermatologic surgery (dermasurgery) is performed by all dermatologists. Surgery is an integral part of dermatology residency training; thus all dermatologists are well trained in cutaneous surgery. In North America specialized training through a 1 year dermatologic surgery fellowship is available upon completion of the dermatology residency, and usually focuses on training in Mohs' micrographic surgery. Most dermatologic surgeons
who have a special interest in this field apply for fellowship status with the American College of Mohs Surgery
; or the American Society for Dermatologic Surgery
Techniques available to a dermatologic surgeon include lasers, traditional scalpel surgery, electrosurgery, cryosurgery, photodynamic therapy, liposuction, blepharoplasty (cosmetic eyelid surgery), minimally-invasive facelift surgery (e.g., the S-lift), and a variety of topical and injectable agents such as dermal fillers including fat transfer and hyaluronic acid. Some specially trained dermatologic surgeons perform Mohs surgery, which can be an effective method for the treatment of recurrent, indistinct, or difficult skin cancers.
Any mole that is irregular in color or shape should be examined by a dermatologist to determine if it is a malignant melanoma
, the most serious and life-threatening form of skin cancer. Following a visual examination and a dermatoscopic exam (an invaluable new instrument that illuminates a mole without reflected light), a dermatologist may biopsy a suspicious mole. If it is malignant, it will be excised in the dermatologist's office.
The first step of any contact with a physician is the medical history. In order to classify a cutaneous eruption, the dermatologist will ask detailed questions on the duration and temporal pattern of skin problems, itching or pain, relation to food intake, sunlight, over-the-counter creams and clothing. When an underlying disease is suspected, an additional detailed history of related symptoms will be elicited (such as arthritis
in a suspected case of lupus erythematosus
Dermatology has the obvious benefit of having easy access to tissue for diagnosis. Physical examination
is generally done under bright light and preferably involves the whole body. At this stage, the doctor may apply Wood's light
, which may aid in diagnosing types of mycosis
or demonstrate the extent of pigmented lesions, or use a dermatoscope
which enlarges a suspected lesion and visualizes it without reflected light. The dermatoscope is helpful in differentiating a benign naevus
or a seborrheic keratosis from a mole. A morphological classification of dermatological lesions
is important in the diagnosis of dermatological disorders. Dermatologic diagnosis is often dependent upon pattern recognition of lesions and symptoms.
or Gram staining
of suspected infectious lesions may identify a pathogen
and help direct therapy.
If the diagnosis is uncertain or a cutaneous malignancy
is suspected, the dermatologic surgeon may perform a small punch biopsy
(using a local anesthetic
) for examination under the microscope by the dermatologist who is a trained dermatopathologist
The skin is obviously accessible to topical local therapy. Antibiotic
creams can help eliminate infections, while inflammatory
skin diseases (such as eczema
) 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
and immune suppressants
or immune enhancing agents
(injection immunotherapy or topical imiquimod) for dermatological diseases or tumors. Isotretinoin
("Accutane") is used for severe cystic acne vulgaris
and often produces a lifetime remission of this disfiguring disease. Isotretinoin prescribing in the U.S. is now controlled by a cumbersome FDA governmental website called iPLEDGE
. Various new modalities of treatment are in the foray; with the advent of laser technology
things are quite promising.
involves the use of ultraviolet light
, often in combination with oral or topical agents, to treat skin disease (e.g., psoriasis
or mycosis fungoides
Surgical intervention by a dermatologic surgeon
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 cancer surgery
), cryosurgery, x-ray, or with the recent topical immune enhancing agent imiquimod
. (See above section on "Dermatologic Surgery
" for more details.)
Psychodermatology and hypnodermatology
involve using hypnosis in combination with other pseudo-psychological therapies to treat skin disorders.
Residency training program in North America
A minimum of 12 years of college and post graduate training is required to become a dermatologist in the United States and Canada. This includes graduation from a 4-year college where they will take Pre-Medicine, then 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 the most competitive in terms of admission. The nation's most prestigious residency training programs include New York University, University of Pennsylvania, Harvard, Mayo Clinic, and University of California, San Francisco (known colloquially as the "Big Five"). Following the successful completion of formal residency training in dermatology (3 years) the physician is qualified to take certifying board examinations (written) 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.
Training programme in Australia
An Australian specialist dermatologist will have completed 4-6 years of medical school (depending on institution), one internship year and at least one year of general medical or surgical service in the public hospital system, prior to becoming eligible 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 all aspects of 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, similarly held over 2 days. Successful candidates may then apply for Fellowship status with the Australasian College of Dermatologists.
Training program in India
To be a dermatologist in India, a minimum of 2 years (for diploma ) or 3 years (for MD) of training is required after graduation from medical school and internship
. The period involves rigorous training in all aspects of general dermatology, cosmetic dermatology, dermatopathology, dermatosurgery, 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 postgraduate qualification awarded is DVD (Diploma in Venereology and Dermatology) and MD (dermatology, venereology and leprosy). Many specialists also go for certification by the national board (for the award of 'diplomate of national board'). The Indian Association of Dermatologists, Venereologists and Leprologists(IADVL)is one of the largest dermatolological associations in the world.
From the basic science of cutaneous genetics
, 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 been among the leaders in the field. 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 dermatologic surgeon.
The work De morbis cutaneis
("On the diseases of the skin" - 1572
) by Geronimo Mercuriali
) is known as the first scientific tractation about Dermatology. Early photographic documentation of skin diseases was produced by Balmanno Squire, Dr. Alfred Hardy, Dr. A. de Montméja, Dr. Howard Franklin Damon, Dr. George Henry Fox and Dr. Oscar G. Mason
in the latter 1800s.