TY - JOUR T1 - Investigation of the hair follicle inner root sheath in scarring and non-scarring alopecia. AU - Horenstein,Marcelo G, AU - Simon,Jessica, PY - 2007/9/21/pubmed PY - 2007/11/14/medline PY - 2007/9/21/entrez SP - 762 EP - 8 JF - Journal of cutaneous pathology JO - J Cutan Pathol VL - 34 IS - 10 N2 - BACKGROUND: Premature desquamation of the inner root sheath (IRS) is described as a defining histologic feature of follicular degeneration syndrome/central centrifugal cicatricial alopecia (CCCA). However, IRS abnormalities have been noted in other types of alopecia. DESIGN: We evaluated the IRS in terminal hair follicles with transverse sections stained with hematoxylin-eosin and Ziehl-Neelsen stains in 22 non-scarring (7 areata and 15 androgenetic) and 21 scarring (13 CCCA, 2 lichen planopilaris, 2 lupus erythematosus, 1 folliculitis decalvans and 3 end stage) alopecia cases. In addition, we evaluated 15 normal controls with longitudinal sections to establish the level of IRS desquamation. RESULTS: The IRS was present in 99.5 +/- 0.01% (mean +/- standard error) of normal follicles at the level of the arrector pili muscle/sebaceous gland/sweat gland coil (L2) and variably present at higher levels. The IRS was present at L2 in 97.9 +/- 1.5% of alopecia areata, 87.4 +/- 5.3% of androgenetic alopecia, 59.3 +/- 7.0% of CCCA and 49.4 +/- 11.3% of other scarring alopecia follicles. CONCLUSIONS: Premature desquamation of the IRS was identified in CCCA; however, it was also noted in other scarring alopecia cases. IRS premature desquamation is a non-specific histologic feature in scarring alopecia and cannot be used alone as a defining feature of CCCA. SN - 0303-6987 UR - https://www.unboundmedicine.com/medline/citation/17880581/Investigation_of_the_hair_follicle_inner_root_sheath_in_scarring_and_non_scarring_alopecia_ L2 - https://doi.org/10.1111/j.1600-0560.2006.00696.x DB - PRIME DP - Unbound Medicine ER -