Nummular dermatitis
Template:Infobox medical condition (new) Nummular dermatitis (commonly known as nummular eczema or discoid eczema) is one of the many forms of dermatitis.<ref name=":0">Template:Cite journal</ref> It is characterized by round or oval-shaped itchy lesions.<ref name="WEIDMAN 58–65">Template:Cite journal</ref> The name comes from the Latin word "nummus," which means "coin."
Signs and symptomsEdit
Nummular dermatitis is characterized by chronic or relapsing itchy coin-sized ovoid-shaped red plaques.<ref>Template:Cite journal</ref><ref>Template:Cite journal</ref> They can occur on the trunk, limbs, face, and hands.<ref name=":0" /><ref name="WEIDMAN 58–65"/><ref>Template:Cite journal</ref>
CausesEdit
Many contact sensitizers or irritants are known to cause contact dermatitis superimposed on nummular dermatitis. Studies have implicated nickel, cobalt, chromate, and fragrance as likely culprits.<ref name=":1" /><ref>Template:Cite journal</ref> Xerosis, or dehydration of skin is also a likely cause.<ref name=":2">Template:Cite journal</ref> Infection with Staphylococcus aureus bacteria or Candida albicans may also play a role.<ref name=":2" />
DiagnosisEdit
Diagnosis of nummular dermatitis is largely via clinical observation. Biopsies are typically not necessary, and cannot be used to rule out other atopic dermatitis or other eczemas.<ref>Template:Cite journal</ref><ref>Template:Cite journal</ref> However, patch testing may be employed to rule out irritants (contact dermatitis) as a cause.<ref name=":1">Template:Cite journal</ref><ref>Template:Cite journal</ref> In children, nummular dermatitis is commonly confused with tinea corporis.<ref name=":2" />
TreatmentEdit
{{ safesubst:#invoke:Unsubst||date=__DATE__ |$B= {{ safesubst:#invoke:Unsubst||date=__DATE__ |$B= Template:Ambox }} }} One of the keys to treatment and prevention involves keeping the skin moisturized. Lotions, creams, and bath oils may help prevent an outbreak. If the condition flares up, a common treatment involves the application of topical corticosteroids. Oral antihistamines may help lessen itching. Avoidance of irritants is a common strategy. More severe cases sometimes respond to ultraviolet light treatment. If the condition occurs only during the sun-less winter months then vitamin D supplement might be an effective treatment.Template:Citation needed
EpidemiologyEdit
The prevalence of nummular dermatitis in the United States is approximately 2 per 1,000.<ref>Template:Cite journal</ref> It is considered a disease of adulthood, for it is rare in children.<ref>Template:Cite journal</ref>