I recently saw an older gentleman who expressed some concern about a rash. With summer approaching and “bathing suit weather” near, he was mainly concerned with the cosmetic effect — and also whether or not it might be contagious.
A detailed history revealed that the rash had started rather suddenly about a year ago and had spread very little since. He has never had a rash in the past, nor is there any family history of rashes. Prior to onset he had not been ill, nor travelling, nor exposed to any new medications.
The rash is not sore or itchy. It’s not really spreading, but after local exposure to heat and/or pressure it seems more prominent for awhile. For example, it’s redder for a short time after lying on a particular side, and on the inner aspects of his knees where they come in contact during sleep.
No over-the-counter treatment has been attempted — since the rash is asymptomatic. One prescribed medication — antifungal Lamisil spray — was tried by another physician, with no effect.
The patient is generally well and active (for someone over 80), with medications taken for diabetes (diagnosed and treated with good control since 2003) and mild hypertension (very recently). He had hip replacements in 2000 and 2003 with metal-on-metal prostheses.
He was diagnosed with hemochromatosis (an incidental finding during routine blood work) in 2005 and treated with three-weekly phlebotomy through 2008 — then every four to six months. His hemoglobin and ferritin remained in the normal range. He still works daily in an administrative job with no known exposure to any environmental toxins. His medications include: Amaryl 1 mg daily, Pariet 20 mg, Temazepam 15 mg hs, ASA 81 mg, Oxycocet tabs prn pain, vitamin E 400 IU, vitamin C 500 mg, multivitamin tablet and (just recently, begun after rash onset) Altace 2.5 mg. None of these prescriptions changed around the time the rash appeared. He takes cinnamon three to four teaspoons a day. He has no known allergies, but reports that eating chocolate has always caused a boil to appear on the tip of his nose.
The rash is spectacularly variegated and widespread. It involves isolated patches somewhat symmetrically on both wrists and forearms. It occurs on the legs, arms, face (slightly) and trunk. It does not appear on palms or soles. The lesions on the wrists have a slightly palpable raised border and central clearing. The rash on the back is also slightly palpable with a raised border and central clearing. All areas blanch with pressure.
I reassured the patient that it was highly unlikely that the condition was contagious, and arranged an appointment with a dermatologist. As an interim experimental measure, Elocom cream was applied twice a day for two weeks to a small specific area on the inner aspect of the right knee. No change occurred.
The dermatologist saw the patient two weeks later, and confirmed my suspicions about this rash. What was it?
As I had suspected, this rash was confirmed by the dermatologist to be a spectacular case of Granuloma annulare, which more typically presents as just one or a few small lesions in family practice. I had never seen such a spectacularly widespread and variegated version — but I guess that’s why we have consultants. No treatment is required and the natural history of the rash is unpredictable. The patient remains well — the only investigation prescribed by the dermatologist being a chest x-ray to rule out hilar adenopathy. No biopsy was felt to be necessary.
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