Multivariate Analysis of Factors Associated with the Koebner Phenomenon in Vitiligo: An Observational Study of 381 Patients

BACKGROUND: The Koebner phenomenon (KP) is a common entity observed in dermatological disorders. The reported incidence of KP in vitiligo varies widely. Although the KP is frequently observed in patients with viltiligo, the associated factors with KP has not been established yet. OBJECTIVE: The aim is to estimate the prevalence of KP in vitiligo patients and to investigate the associated factors with KP among vitiligo characteristics. METHODS: A cross-sectional observational study was conducted using 381 vitiligo patients. Demographic and clinical information was obtained via the completion of Vitiligo European Task Force (VETF) questionnaires. Patients with positive history of KP were extracted from this vitiligo database. Multivariate analysis was performed to assess associations with KP. RESULTS: The median age of cases was 24 years (range, 0.6~76). In total, 237 of the patients were male (62.2%). Vitiligo vulgaris was the most common type observed (152/381, 39.9%). Seventy-two percent (274/381) patients did not exhibit KP, whereas 28.1% (107/381) of patients exhibited this condition. Multivariable analysis showed the following to be independent factors with KP in patients with vitiligo: the progressive disease (odds ratio [OR], 1.82; 95% confidence interval [95% CI], 1.17~2.92; p=0.041), disease duration longer than 5 years (OR, 1.92; 95% CI, 1.22~2.11; p=0.003), and body surface area more than 2% (OR, 2.20; 95% CI, 1.26~3.24; p<0.001). CONCLUSION: Our results suggest that KP may be used to evaluate disease activity and investigate different associations between the clinical profile and course of vitiligo. Further studies are needed to predict the relationship between KP and responsiveness to therapy.

Profile of mycosis fungoides in 43 Saudi patients

Mycosis fungoides [MF] is a rare disease; and to our knowledge, there are no reports on its profile in Arabs. The objective of this study was to preliminarily analyze the clinical characteristics of MF patients seen in our institution. Retrospective review of 140 patients with pathologic or clinical diagnosis or differential diagnosis of MF for the period 2000-2006. Pathology reports with diagnosis or differential diagnosis of MF were retrieved and suspected cases were identified and reviewed. For pathologically confirmed cases, sociodemographic, clinical, laboratory, and radiological details were collected. Details of staging, treatment modalities, and disease status at the last follow-up were retrieved. A total of 43 pathologically confirmed MF patients [skin phototypes IV and V] with a mean age at diagnosis of 33.5 years were reviewed. This comprised 29 males [M:F ratio, 2:1], and the majority [86%] of patients had early-stage [I and II] MF. Twenty-one [48.8%] patients had classic MF; 18 [41.8%], hypopigmented MF; and 4 [9.3%], other variants. The male-to-female ratio was higher in the hypopigmented [3.5:1] than in the classic variant [1.6:1]. The mean age at diagnosis was lower in the hypopigmented compared to the classic variant [25 versus 38.8 years, P=.019]. The mean duration of follow-up was 27.6 months [range, 1-98 months]. At the final assessment, 4 [9.5%] patients recovered; whereas 35 [83.3%] had MF skin disease; 1 had [2.4%] extracutaneous disease; and 2 [4.8%] died of MF. MF tends to affect younger Saudi patients. The hypopigmented variant constitutes a significant proportion of MF cases, especially in younger patients