Central Centrifugal Cicatricial Alopecia (CCCA)

Abstract

124Central centrifugal cicatricial alopecia (CCCA) is the most common cicatricial alopecia in African American women. It is characterized by chronic and progressive central scalp hair loss, which starts on the crown and spreads peripherally but spares the lateral, frontal and posterior scalp (Figure 18.1). Advanced cases show a smooth and shiny scalp (Figure 18.2). Figure 18.1 (A, B) Hair loss involving the crown and vertex that spreads peripherally but spares the lateral, frontal and posterior scalp is typical for central centrifugal cicatricial alopecia. https://s3-euw1-ap-pe-df-pch-content-public-p.s3.eu-west-1.amazonaws.com/9780429457609/a1a07c34-5530-453d-aca4-02e4ee680a4a/content/fig18_1.tif"/> Figure 18.2 Central centrifugal cicatricial alopecia; note the smooth and shiny scalp in a more advanced case. https://s3-euw1-ap-pe-df-pch-content-public-p.s3.eu-west-1.amazonaws.com/9780429457609/a1a07c34-5530-453d-aca4-02e4ee680a4a/content/fig18_2.tif"/> There might be slight erythema and grouping of 2–3 hairs coming out of one follicle (polytrichia). Symptoms can range from none to soreness, itching and burning. Hair breakage on the vertex has been reported as a possible early clinical presentation of CCCA that has been confirmed on pathology (Figure 18.3). Figure 18.3 This young patient has no clear patches of hair loss but complaints of hair breakage on the central scalp, which led to the diagnosis of CCCA on histology. https://s3-euw1-ap-pe-df-pch-content-public-p.s3.eu-west-1.amazonaws.com/9780429457609/a1a07c34-5530-453d-aca4-02e4ee680a4a/content/fig18_3.tif"/> Early cases are difficult to distinguish from androgenetic alopecia and pathology is very important to make the diagnosis (Figures 18.1 and 18.4). Figure 18.4 (A) This case of androgenetic alopecia demonstrates clinical similarity to CCCA. (B) Trichoscopy shows irregular pigmented network and hair shaft variability, which indicates towards AGA (×40). However, in such cases a biopsy is necessary to confirm the diagnosis. https://s3-euw1-ap-pe-df-pch-content-public-p.s3.eu-west-1.amazonaws.com/9780429457609/a1a07c34-5530-453d-aca4-02e4ee680a4a/content/fig18_4.tif"/> CCCA can present as “patchy”-interconnected alopecic patches with a maze-like appearance in the occipital and parietal scalp (Figure 18.5). Figure 18.5 (A) Patchy CCCA presents with a pattern of hairless areas among preserved islands of hair resembling (B) a maze-like growth of moss on a stone; this type involves also the parietal and occipital scalp. https://s3-euw1-ap-pe-df-pch-content-public-p.s3.eu-west-1.amazonaws.com/9780429457609/a1a07c34-5530-453d-aca4-02e4ee680a4a/content/fig18_5.tif"/> Small series have shown that CCCA can be inherited in an autosomal dominant fashion, with a partial penetrance and a strong modifying effect of hairstyling and sex. Upregulation of genes implicated in fibroproliferative disorders (platelet-derived growth factor gene [PDGF], collagen I gene [COL I], collagen III gene [COL III], matrix metallopeptidase 1 gene [MMP1], matrix metallopeptidase 2 gene [MMP2], matrix metallopeptidase 7 gene [MMP7] and matrix metallopeptidase 9 gene [MMP9]) has been detected in patients with CCCA. Prevalence of PADI3 mutation was higher among patients with CCCA than in a control cohort of women of African ancestry according to a recent exome sequencing study. CCCA has been described in teenage children, which adds weight to the concept that genetic susceptibility may play a significant role in the pathogenesis. On trichoscopy, the most common features are: (1) the peripilar gray/white halo that is a specific and sensitive dermatoscopic sign for CCCA (Figure 18.6, see also Chapter 5); (2) irregular honeycomb-pigmented network that represents the hyperpigmented rete ridges and the hypomelanotic dermal papillae (Figure 18.6); (3) irregularly distributed pinpoint white dots (Figure 18.7); (4) hair shaft variability that corresponds to the decreased terminal:vellus ratio observed on histology (Figure 18.7) and (5) white patches that represent follicular dropout (Figure 18.8). Less frequent are perifollicular and interfollicular scales that should not be mistaken for peripilar casts since the latter are tightly attached tubular structures that encircle the proximal portion of the hair shafts, and individual black dots or broken hairs. Of note, there are no peripilar casts in CCCA (Figure 18.9). Figure 18.6 Loss of follicular openings, irregular pigmented network and peripilar white/gray halo are typical features on trichoscopy of CCCA (×40). https://s3-euw1-ap-pe-df-pch-content-public-p.s3.eu-west-1.amazonaws.com/9780429457609/a1a07c34-5530-453d-aca4-02e4ee680a4a/content/fig18_6.tif"/> Figure 18.7 Irregular distribution of pinpoint white dots, irregular pigmented network, peripilar white/gray halo, black dots and a broken hair (flame hair) in CCCA. Note also the hair shaft variability (×20). https://s3-euw1-ap-pe-df-pch-content-public-p.s3.eu-west-1.amazonaws.com/9780429457609/a1a07c34-5530-453d-aca4-02e4ee680a4a/content/fig18_7.tif"/> Figure 18.8 White patches in CCCA correspond to areas of follicular dropout and black dots correspond to the destroyed hair follicle (×20). https://s3-euw1-ap-pe-df-pch-content-public-p.s3.eu-west-1.amazonaws.com/9780429457609/a1a07c34-5530-453d-aca4-02e4ee680a4a/content/fig18_8.tif"/> Figure 18.9 The distinction between perifollicular and interfollicular scaling in (A) CCCA and (B) peripilar casts in lichen planopilaris (×20). https://s3-euw1-ap-pe-df-pch-content-public-p.s3.eu-west-1.amazonaws.com/9780429457609/a1a07c34-5530-453d-aca4-02e4ee680a4a/content/fig18_9.tif"/>