OBJECTIVE: This article aimed to provide an update on the evaluation, diagnosis, and treatment of nummular eczema.
METHODS: A PubMed search was performed in using the key terms "nummular eczema", "discoid eczema", OR "nummular dermatitis". The search strategy included meta-analyses, randomized controlled trials, clinical trials, observational studies, and reviews. The search was restricted to English literature. The information retrieved from the above search was used in the compilation of the present article. Patents were searched using the key terms "nummular eczema", "discoid eczema", OR "nummular dermatitis" in www.google.com/patents and www.freepatentsonline.com.
RESULTS: Nummular eczema is characterized by sharply defined, oval or coin-shaped, erythematous, eczematous plaques. Typically, the size of the lesion varies from 1 to 10cm in diameter. The lesions are usually multiple and symmetrically distributed. Sites of predilection include the lower limbs followed by the upper limbs. The lesions are usually intensely pruritic. The diagnosis is mainly clinical based on the characteristic round to oval erythematous plaques in a patient with diffusely dry skin. Nummular eczema should be distinguished from other annular lesions. Dermoscopy can reveal additional features that can be valuable for correct diagnosis. Biopsy or laboratory tests are generally not necessary. However, a potassium hydroxide wet-mount examination of skin scrapings should be performed if tinea corporis is suspected. Because contact allergy is common with nummular eczema, patch testing should be considered in patients with chronic, recalcitrant nummular eczema. Avoidance of precipitating factors, optimal skin care, and high or ultra-high potency topical corticosteroids are the mainstay of therapy. Recent patents related to the management of nummular eczema are also discussed.
CONCLUSION: With proper treatment, nummular eczema can be cleared over a few weeks, although the course can be chronic and characterized by relapses and remissions. Moisturizing of the skin and avoidance of identifiable exacerbating factors, such as hot water baths and harsh soaps may reduce the frequency of recurrence. Diseases that present with annular lesions may mimic nummular eczema and the differential diagnosis is broad. As such, physicians must be familiar with this condition so that an accurate diagnosis can be made, and appropriate treatment initiated.
RESULTS: Escherichia coli KUB-36 was selected in this study since it has the capability to produce seven SCFA extracellularly. It produced acetic acid as the main SCFA. It is a non-exotoxin producer and hence, it is a safe gut microbiota. The IC50 values indicated that the E. coli KUB-36 metabolites treatment elicited more potent cytotoxicity effect on MCF7 breast cancer cell as compared to colon cancer and leukemia cancer cells but exhibited little cytotoxic effects on normal breast cell. Furthermore, E. coli KUB-36 metabolites and individual SCFA could affect inflammatory responses in lipopolysaccharide-induced THP-1 macrophage cells since they suppressed inflammatory cytokines IL-1β, IL-6, IL-8 and TNF-α well as compared to the control, whilst inducing anti-inflammatory cytokine IL-10 expression.
CONCLUSION: SCFA producing E. coli KUB-36 possessed vast potential as a beneficial gut microbe since it is a non-exotoxin producer that exhibited beneficial cytotoxic effects on cancer cells and elicited anti-inflammatory activity simultaneously. However, the probiotic characteristic of E. coli KUB-36 should be further elucidated using in vivo animal models.