Zinc pyrithione is a shampoo ingredient that has been shown to be safe and effective for dandruff and scalp psoriasis. It is thought to decrease the cell turnover rate in hyperproliferative dermatoses such as psoriasis, and also has fungistatic and antimicrobial activity, although its exact mode of action is unknown. In psoriasis, external factors, such as trauma, infection and drugs, may provoke aggravated manifestations of psoriatic skin lesions. Rarely, irritant or allergic mechanisms are likely causes of psoriatic flare and Kobnerization. A patient had had stable psoriasis for 25 years and no any other skin disease. Within 20 days, she developed an aggravated scaly erythematous patch on the scalp, where a shampoo had been applied, and simultaneously developed pustular psoriasis on both forearms. Patch testing showed a relevant sensitization to zinc pyrithione, and we observed symptomatic aggravation by provocation testing with zinc pyrithione shampoo. We report a rare case of psoriasis aggravated by the induction of allergic contact dermatitis from zinc pyrithione after using antidandruff shampoo.

Telomerase activity is usually detected in most tumor tissues but not in normal tissues. Recently, there is increasing evidence that telomerase activity is associated with cell proliferation without malignancy, whereas there is little information about telomerase activity and its relationship with cell proliferation in chronic hyperproliferative skin diseases. Thus, we studied telomerase activity in skins from 10 patients with psoriasis and compared telomerase activity with the expression of Ki-67, a proliferation marker, using immunohistochemical staining. The effect of retinoic acid on the telomerase activity in HaCaT cells was also evaluated. Telomerase activity was detected in 7 (70%) of 10 lesional skins of psoriasis and none of the nonlesional skin. Telomerase activity in lesional skin was significantly associated with Ki-67 labelling index. Retinoic acid treatment on HaCaT cells inhibited telomerase activity, which correlated with inhibition of cell proliferation by the agent. The results of our study represent another example that shows telomerase activity correlates with cellular proliferation. Further studies on the regulation of the telomerase are needed to understand the cellular factors involved in controlling telomerase activity.

No abstract

BackgroundA small subset of adolescents atopic dermatitis (AD) tends to persist. This also leads to get more antibiotics exposure with advancing years. Antibiotic resistance has been regarded as a serious problem during Staphylococcus aureus treatment, especially methicillin-resistant S. aureus (MRSA).ObjectiveIt was investigated the S. aureus colonization frequency in the skin lesions and anterior nares of adolescent AD patients and evaluated the changes in S. aureus antimicrobial susceptibility for years.MethodsPatients who visited our clinic from September 2003 to August 2005 were classified into group A, and patients who visited from August 2010 to March 2012 were classified into group B. To investigate the differences with regard to patients' age and disease duration, the patients were subdivided into groups according to age. Lesional and nasal specimens were examined.ResultsAmong the 295 AD patients, the total S. aureus colonization rate in skin lesions was 66.9% (95/142) for group A and 78.4% (120/153) for group B. No significant changes in the systemic antimicrobial susceptibilities of S. aureus strains isolated from adolescent AD patients were observed during about 10-year period. The increased trend of MRSA isolation in recent adolescent AD outpatients suggest that the community including school could be the source of S. aureus antibiotic resistance and higher fusidic acid resistance rates provides evidence of imprudent topical use.ConclusionRelatively high MRSA isolation and fusidic acid resistance rates in recent AD patients suggest that the community harbors antibiotic-resistant S. aureus.

No abstract