Dermatologists can be incredibly efficient and cost-effective in their practices because of their background and training in medicine and surgical procedures. We are not often acknowledged or appreciated for this by health insurance companies. The skin is the largest  organ in the body and plays an important role in immune surveillance by blocking out invaders (organisms and chemicals) from the outside environment. The skin’s immune system is also capable of recognizing allergens and antigens including cancer cells from the  bloodstream and reacting to them appropriately. When either the external barrier or the internal immune system malfunction, by not recognizing or by under- or over-reacting to the invader, the visible result is a rash.

What is a Rash? A rash is a layman’s term for any abnormality in the surface texture, color, or sensation of the skin. “Rash” is a word used by patients and doctors to describe symptoms and results of examination, but is entirely non-specific and does not say what the skin disease is. That is the role of the dermatologist, the specialist of the skin, hair, and nails, and sometimes mucous membranes. It may be difficult to name a rash because there are thousands of possibilities. If a dermatologist cannot recognize a skin disease immediately by its appearance, he or she may call it dermatitis which is inflammation of the skin, and narrow down the potential diagnoses on the basis of the history of onset, family history, body distribution, pattern of the skin disease, and symptoms. If the list is very short, say 2 or 3 possibilities, a treatment may be prescribed at that first visit to be evaluated at a follow-up visit after an interval of 1-3 weeks. If the condition is markedly improved or clear, no further tests or visits may be necessary.

But life is usually not so straightforward, is it?  Let’s say the dermatologist treated the nonspecific dermatitis with a potent steroid cream, and it simply didn’t respond after 2 weeks. He might suspect that the rash was either a fungal infection (called “ringworm” in common parlance) or a steroid-resistant inflammation such as psoriasis or eczema. The next step would be to perform a scraping of the superficial skin scales or dandruff at the edge of the lesion and examine it under the microscope himself during the visit. The experienced eye can recognize fungal or yeast elements in the skin cells. If positive, an anti-fungal cream or pill may prescribed for cure. If negative, then a deeper skin biopsy may be performed for interpretation by a dermatopathologist for a definitive diagnosis.

Case Study–Eczema vs. Fungal Infection  

A woman sought a second opinion for an itchy red bumpy rash on her thigh. She had seen her primary care doctor who performed a skin biopsy which was interpreted by the general pathologist as “consistent with eczema.” On the basis of the report, the doctor prescribed various potent steroid creams which were ineffective after several weeks of multiple office calls and expensive prescriptions. In fact, the rash had gotten worse and spread to the wrist. Finally, the doctor told the patient she could not help anymore. In my initial visit with the patient, I suspected a fungal infection because of the complete resistance to potent steroid medication and the appearance or partial rings at the edge of the rash. Because it is always possible to have 2 skin diseases at the same time, I performed biopsies of the rash on the thigh and wrist. Both biopsy specimens revealed fungal infection under the microscope. When I received this result 3 days later, I called in the prescription for the anti-fungal cream econazole and stopped use of the steroid cream. When she returned 2 weeks after the first visit for suture removal and re-evaluation, her skin was almost clear. She was asked to continue the cream to complete 4 weeks of treatment for the cure. In summary, in one specialty visit, the diagnosis was obtained;the appropriate treatment was called in, and the follow-up visit confirmed the excellent response to therapy.