Clinicopathological evaluation of patients with rippled pattern pigmentation of the skin: A single-center study.

The aim of the present study was to investigate the clinical association between rippled pattern pigmentation and the positivity of histopathological analysis for amyloid. A total of 50 patients (90% women) with rippled pattern pigmentation referring to Dermatology Clinic of Shahid Faghihi Hospital, Shiraz, Iran, in 2015 participated in this study. Two biopsies were performed for all the cases from the most frequently affected sites. The specimens were evaluated for amyloid deposits with hematoxylin-eosin (H&E), Congo red (CR), and crystal violet (CV) stains. The upper back was the most frequently affected area in the patients. Family history (28%), atopy (14%), pruritus as a common finding (86%), and history of friction (54%) were positive. The prevalence of disease was higher in patients with skin photo Type 3. Amyloid deposit was not detected in most patients by these stains. No statistically significant difference was found between the amyloid positive cases stained with H&E, CR, and CV (p-value > 0.05). Only the difference in positive results between biopsy number 2 and the total biopsy (1 and 2) was significant (p-value < .05). In conclusion, it seems that it is useful to increase the number of biopsies and other more sensitive staining methods to detect small focal amyloid deposits.