Francesca Cheung, MD CCFP,¹ Jeffrey Law and Lindsey Chow, ²

CLINICAL TOOLS

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Francesca Cheung, MD CCFP, is a family physician with a special interest in dermatology. She received the Diploma in Practical Dermatology from the Department of Dermatology at Cardiff University in Wales, UK. She is practising at the Lynde Centre for Dermatology in Markham, Ontario and works closely with Dr. Charles Lynde, MD FRCPC, an experienced dermatologist. In addition to providing direct patient care, she acts as a sub-investigator in multiple clinical studies involving psoriasis, onychomycosis, and acne.

Abstract
Mammary Paget disease (PD) is a less common form of breast cancer which involves the nipple-areola complex and occurs almost exclusively in females. Erythema, skin thickening, pruritus, burning sensation, inversion of the nipple, ulceration, serosanguineous nipple discharge are common clinical symptoms. Approximately 1-4% of female breast carcinoma are associated with PD of the nipple-areola complex. A biopsy including the dermal and subcutaneous tissue should be performed on all suspicious lesions of the nipple-areola complex for accurate diagnosis. The first line treatment of mammary PD is mastectomy (radical or modified) and lymph node clearance for patients with a palpable mass and underlying invasive breast carcinoma. The prognosis of mammary PD is determined by the disease stage and is similar to that of other types of breast cancer.
Key Words: Mammary Paget disease, breast cancer, nipple-areola complex, metastasis.

Francesca Cheung, MD CCFP, is a family physician with a special interest in dermatology. She received the Diploma in Practical Dermatology from the Department of Dermatology at Cardiff University in Wales, UK. She is practising at the Lynde Centre for Dermatology in Markham, Ontario and works closely with Dr. Charles Lynde, MD FRCPC, an experienced dermatologist. In addition to providing direct patient care, she acts as a sub-investigator in multiple clinical studies involving psoriasis, onychomycosis, and acne.

Abstract
Herpes simplex viruses (HSVs) are DNA viruses that present as vesicles in clusters on an erythematous base. Infection occurs when close contact between an individual without antibodies against the virus and a person shedding the virus takes place. Most HSV infections are self-limited. Lesions tend to reappear at or near the same location of the initial site of infection. Systemic symptoms such as fever, malaise and acute toxicity may appear, especially in primary infection. A viral culture from the skin vesicles can identify up to 80 to 90% of untreated infection early in the course. Antiviral treatments aim at shortening the disease course and preventing viral dissemination and transmission. Treatments are most effective when they are administered at the first sign of symptom onset.

Francesca Cheung, MD CCFP, is a family physician with a special interest in dermatology. She received the Diploma in Practical Dermatology from the Department of Dermatology at Cardiff University in Wales, UK. She is practising at the Lynde Centre for Dermatology in Markham, Ontario and works closely with Dr. Charles Lynde, MD FRCPC, an experienced dermatologist. In addition to providing direct patient care, she acts as a sub-investigator in multiple clinical studies involving psoriasis, onychomycosis, and acne.

Abstract
Tinea incognito is a superficial dermatophyte infection in which the clinical appearance of the symptoms has been altered by inappropriate treatments, such as topical corticosteroids.
Dermatophyte infection may result from contact with infected humans, animals, or inanimate objects. An erythematous, pruritic, annular and scaly plaque is characteristic of a symptomatic infection. A potassium hydroxide (KOH) examination of skin scrapings is usually diagnostic. If topical corticosteroids have been applied recently, the amount of surface scales may be reduced and may lead to false negative results. Topical therapy is the first line treatment for localized infections. Systemic antifungals should be used in extensive condition, immunosuppression, resistance to topical antifungal therapy.

Francesca Cheung, MD CCFP, is a family physician with a special interest in dermatology. She received the Diploma in Practical Dermatology from the Department of Dermatology at Cardiff University in Wales, UK. She is practising at the Lynde Centre for Dermatology in Markham, Ontario and works closely with Dr. Charles Lynde, MD FRCPC, an experienced dermatologist. In addition to providing direct patient care, she acts as a sub-investigator in multiple clinical studies involving psoriasis, onychomycosis, and acne.

Abstract
Hairy tongue, or known as lingua villosa, is a result of hypertrophy, elongation, and defective desquamation of the filiform papillae of the tongue. This condition may present in a variety of colors depending on the specific etiology. Etiologies of hairy tongue include poor oral hygiene, lack of mechanical stimulation and debridement of the tongue, the use of medications (especially broad-spectrum antibiotics), and therapeutic radiation of the head and the neck. This condition is also commonly seen in people having high consumption in coffee and tea, heavy use of tobacco, individuals addicted to drugs, patients who are HIV positive, and intravenous drug users. In most cases, non-pharmacologic interventions are used for the management of hairy tongue. Treatment involves brushing the tongue with a toothbrush or using a commercially available tongue scraper to retard the growth or to remove elongated filiform papillae. If Candida albicans is present, topical antifungal medications are used for patients who are symptomatic.
Key Words: Hairy tongue, Lingua villosa, Glossopyrosis, Halitosis.

Francesca Cheung, MD CCFP, is a family physician with a special interest in dermatology. She received the Diploma in Practical Dermatology from the Department of Dermatology at Cardiff University in Wales, UK. She is practising at the Lynde Centre for Dermatology in Markham, Ontario and works closely with Dr. Charles Lynde, MD FRCPC, an experienced dermatologist. In addition to providing direct patient care, she acts as a sub-investigator in multiple clinical studies involving psoriasis, onychomycosis, and acne.

Abstract
Erythema ab igne (EAI) is a localized hypermelanosis with erythema in a reticulated pattern. It is triggered from repeated exposure to heat and infrared radiation. Actinic keratosis, squamous cell carcinoma, and Merkel cell carcinoma have been reported in patients after chronic exposure to infrared radiation. EAI is diagnosed based on clinical symptoms. If the diagnosis is uncertain, a skin biopsy may be performed. Early in the disease process, elimination of the heat source may lead to complete resolution of the symptoms.