Dermatology: Practical and Conceptual Research Letter | Dermatol Pract Concept. 2023;13(4):e2023229 1 Folliculitis Decalvans with Frontal Fibrosing Alopecia in a Dark Phototype: Presentation of Folliculitis Decalvans and Lichen Planopilaris Phenotypic Spectrum Basma Karrakchou1, Amani Fliti1, Amal El Fiboumi2, Fouad Kettani3, Karima Senouci1, Mariame Meziane1 1 Dermatology and Venereology Department, Ibn Sina Hospital, Mohammed V University of Rabat, Morocco 2 Department of medicine, Moulay Youssef Hospital, Mohammed V University of Rabat, Morocco 3 Histopathology Center of the United Nations, Rabat, Morocco Key words: folliculitis decalvans, frontal fibrosing alopecia, lichen planopilaris, phenotypic spectrum Citation: Karrakchou B, Fliti A, El Fiboumi A, Kettani F, Senouci K, Meziane M. Folliculitis Decalvans with Frontal Fibrosing Alopecia in a Dark Phototype: Presentation of Folliculitis Decalvans and Lichen Planopilaris Phenotypic Spectrum. Dermatol Pract Concept. 2023;13(4):e2023229. DOI: https://doi.org/10.5826/dpc.1304a229 Accepted: April 13, 2023; Published: October 2023 Copyright: ©2023 Karrakchou et al. This is an open-access article distributed under the terms of the Creative Commons Attribution-NonCommercial License (BY-NC-4.0), https://creativecommons.org/licenses/by-nc/4.0/, which permits unrestricted noncommercial use, distribution, and reproduction in any medium, provided the original authors and source are credited. Funding: None. Competing Interests: None. Authorship: All authors have contributed significantly to this publication. Corresponding Author: Basma Karrakchou: M.D. Dermatology and Venereology Department, Ibn Sina Hospital, Mohammed V University, Rabat, Morocco. orcid number: https://orcid.org/0000-0001-5509-5412 E-mail adress: karrakchou.basma@gmail.com Introduction Lichen planopilaris (LPP) and folliculitis decalvans (FD) are two primary scarring alopecias recently associated in a phe- notypic spectrum in which they occur simultaneously or in a bi-phasic presentation, either in the same scalp location or in different scalp areas [1]. We report a sequential onset of vertex FD and frontal fibrosing alopecia (FFA), a variant of LPP, as an exceptional presentation of this spectrum in phototype V. Case Presentation A 42-year-old premenopausal woman presented with a 10-year history of vertex pustules and crusts leading to scarring patches of alopecia. Nine years later, she presented pruritus in the frontal hairline. The physical examination found a pho- totype V patient with two vertex keloid patches of alopecia measuring 6 cm and 4 cm in diameter respectively, contain- ing tufts, follicular pustules, hemorrhagic crusts, milky-red areas, and dilated vessels on trichoscopy (Figure 1, A and C). 2 Research Letter | Dermatol Pract Concept. 2023;13(4):e2023229 There was an associated 2.5 cm linear frontal hairline reces- sion with trichoscopy showing peripilar hyperkeratosis and erythema, tubular hair casts, and yellow dots (Figure 1, B and D). No vellus hairs were seen. Additional eyebrow loss covered by micropigmentation, facial papules, and facial hy- perpigmentation were noticed. A diagnosis of FD associated with FFA and lichen planus pig- mentosus was confirmed by histopathology (Figure 2, A-D). No bacterial sample was taken from vertex patches of alope- cia due to ongoing oral doxycycline (50 mg twice a day) at that time, with no improvement after 6 months. The decision was made to cease treatment and to prescribe oral low-dose isotretinoin (0.2 mg/kg per day for at least 6 months), in- tralesional injections of corticosteroids every 6 weeks for FFA and FD, and topical fusidic acid twice a week for FD. Within one year of treatment, FFA stabilization was achieved with no more peripilar erythema and hyperkeratosis, no hair loss progression, and no hair regrowth. A subsidence of keloid FD scars was obtained with persistence of some pustules, which needed the adjunction of oral azithromycin (500 mg per day, 3 days per week for 3 weeks) for remis- sion. Currently, the patient is still under treatment, with a taper-off of isotretinoin dose after one year (0.1 mg/kg per day), in the view of its discontinuation. Figure 1. (A) Clinical aspect of folliculitis decalvans: 2 vertex patches of alopecia with tufted hairs, pustules and crusts on an underlying keloid scar. (B) Front view showing an associated frontal fibrosing alopecia, and lichen planus pigmentosus. (C) Vertex trichoscopy: pustules and hemorrhagic crusts surrounding tufts of more than 5 hairs. There were cicatricial milky-red areas with dilated vessels and no follicular openings. (D) Frontal hairline trichoscopy: perifollicular erythema, peripilar hyperkeratosis, and tubular hair casts. Absence of vellus hairs was noticed. Yellow dots were seen on dark photo- type and corresponded to sebaceous glands. Research Letter | Dermatol Pract Concept. 2023;13(4):e2023229 3 Conclusions FD and LPP are primary scarring alopecias recently com- bined in the “FD and LPP phenotypic spectrum” (FDLPPPS) [1-5]. To date, mainly vertex scalp LPP cases have been reported in association with FD [1-5]. To the best of our knowledge, only 2 observations described FFA within the phenotypic spectrum, and the two patients were phototype II (Table 1) [1,5]. FFA is prominent in postmenauposal light skinned women. When there is additional lichen planus pigmentosus, as in our case, FFA mostly affects dark phototype females [6]. FD generally occurs in African American young men. And scalp keloid scars are described in FD only when associated with acne keloidalis nuchae, which occurs in 21% [7]. Trichoscopy has a prominent place by showing either sep- arate features of FD and FFA, or a progressive switch from one to another using dynamic trichoscopy [1]. The aspect is then more or less a mixture of FFA activity signs, such as peripilar erythema and scaling, with FD activity patterns, as crusts and pustules. In late stages of scarring alopecia, there are milky-red areas and tufts in FD, and no follicular open- ings in FFA. Histopathology is the hallmark of FDLPPPS’ final diag- nosis, especially when FD and LPP occur in the same area. The condition is characterized by more follicular packs and plasma cells exocytosis over neutrophils [2], and less bacterial infiltrate [8]. Both conditions progress into scarring alopecia, and early diagnosis is then compulsory to an adequate manage- ment based on anti-inflammatory agents (corticosteroids and isotretinoin) associated with oral antibiotics [1-5]. However, there is no consensus in FDLPPPS treatment, and the therapy duration remains to be established. A long-term follow up is also needed to manage the frequent disease flares occurring after treatment completion. Figure 2. (A, B) Histopathology view (Hematoxylin-Eosin stain, (A) low magnification, (B) high magnification) of vertex scalp biopsy showing a dense peripilar neutrophilic infiltrate, infundibular pustule, and plasma cell exocytosis. They de- struct focally hair shafts. Fibrosis is noted in deep dermis. (C, D) Histopathology aspect (Hematoxylin-Eosin stain, (C) low magnification, (D) high magnification) of frontal hairline scalp biopsy: isthmic and infundibular perifollicular hyperkera- tosis associated with a moderate dermic lymphocytic infiltrate and dense fibrosis. 4 Research Letter | Dermatol Pract Concept. 2023;13(4):e2023229 Ta b le 1 . L it er at ur e re po rt ed c as es o f Fr on ta l F ib ro si ng A lo pe ci a as so ci at ed w it h Fo lli cu lit is D ec al va ns Pa ti en t A g e (y ), G en d er Fi tz p at ri ck p h o to ty p e O n se t C lin ic al a sp ec t Tr ic h o sc o p ic a sp ec t H is to lo g y B ac te ri al cu lt u re (s ca lp s w ab ) Tr ea tm en t O u tc o m e R ef er en ce # 1 42 , F II C on co m it an t Fr on ta l h ai rl in e re ce ss io n an d ve rt ex a re a of sc ar ri ng a lo pe ci a. Fr on ta l t ri ch os co py : pe ri pi la r hy pe rk er at os is a nd er yt he m a co ns is te nt w it h FF A . V er te x tr ic ho sc op y: tu ft s, c ru st s, fo lli cu la r pl ug gi ng , an d pu st ul es co m pa ti bl e w it h FD . FF A : p er i- is th m ic fib ro si s an d ly m ph oc yt ic in fil tr at e FD : P ol yt ri ch ia , pe ri fo lli cu la r ne ut ro ph ili c in fil tr at e an d m ic ro ab ce s. M SS A Ly m ec yc lin e 40 8m g bd f ol lo w ed b y or al an d to pi ca l f us id ic ac id f or 3 w ee ks , an d or al z in c su lf at e 12 5m g bd In te rm it te nt re cu rr en ce s co nt ro le d w it h in te rm it te nt to pi ca l a nd o ra l fu si di c ac id an d to pi ca l co rt ic os te ro id s. [1 ] C as e 9 2 65 , F II Se qu en ti al : FF A t he n FD Pu st ul ar f ro nt al ha ir lin e al op ec ia . Fr on ta l t ri ch os co py : pe ri pi la r hy pe rk er at os is er yt he m a an d pu st ul es . Fr on ta l h ai rl in e sc al p: P er if ol lic ul ar ly m ph oc yt ic d er m ic in fil tr at e an d pr es en ce of p la sm a ce lls . In tr ae pi de rm al p us tu le w it h ne ut ro ph ils w er e pr es en t. St er ile To pi ca l co rt ic os te ro id s fo r 1  m on th . N o di se as e fla re o cc ur ed w it hi n 3 m on th s of fo llo w u p. [5 ] O ur pa ti en t 42 ,F V Se qu en ti al FD t he n FF A L in ea r fr on ta l ha ir lin e re ce ss io n an d tw o ve rt ex ke lo id p at ch es o f al op ec ia . Fr on ta l t ri ch os co py : pe ri pi la r hy pe rk er at os is , sl id in g sh ea th s, pe ri fo lli cu la r er yt he m a, a nd ab se nc e of v el lu s ha ir s. V er te x tr ic ho sc op y: tu ft s, p us tu le s, a nd cr us ts , a ss oc ia te d w it h ci ca tr ic ia l m ilk y- re d ar ea s an d di la te d ve ss el s. FF A : i nf un di bu la r hy pe rk er at os is a nd de rm ic ly m ph oc yt ic in fil tr at e w it h fib ro si s. FD : m ul ti co up ou nd h ai r st ru ct ur es a nd p la sm a ce lls e xo cy to se w it h ne ut ro ph ili c in fil tr at e an d de rm ic fi br os is . N ot pe rf or m ed D ox yc yc lin es 5 0m g bd f ol lo w ed b y lo ng c ou rs e or al is ot re ti no in 2 0m g/ d an d in tr al es io na l co rt ic os te ro id s, an d to pi ca l f us id ic ac id . A dd it io na l or al a zi th ro m yc in 50 0m g/ d fo r 3d ay s pe r w ee k du ri ng 3 w ee ks w er e pr es cr ib ed . St ab ili za ti on of F FA , su bs id en ce o f ke lo id p at ch es of a lo pe ci a an d dr yi ng o f FD le si on s w it hi n 1 ye ar . FD = f ol lic ul it is d ec al va ns ; F FA = f ro nt al f ib ro si ng a lo pe ci a. Research Letter | Dermatol Pract Concept. 2023;13(4):e2023229 5 report of two paediatric cases. J Eur Acad Dermatol Venereol. 2021;35(10):e674-e676. DOI: 10.1111/jdv.17379. PMID: 34014598. 4. Zhang X, Zhu M, Zhou J, Wu S, Liu J, Qin Q. Folliculitis De- calvans and Lichen Planopilaris Phenotypic Spectrum: A Case Report. Clin Cosmet Investig Dermatol. 2022;15:993-996. DOI: 10.2147/CCID.S365566. PMID: 35677221. PMCID: PMC9167836. 5. Lobato-Berezo A, González-Farré M, Pujol RM. Pustular frontal fibrosing alopecia: a new variant within the folliculitis decal- vans and lichen planopilaris phenotypic spectrum? Br J Der- matol. 2022;186(5):905-907. DOI: 10.1111/bjd.20962. PMID: 34939665. 6. Pirmez R, Duque-Estrada B, Donati A, et al. Clinical and dermo- scopic features of lichen planus pigmentosus in 37 patients with frontal fibrosing alopecia.  Br J Dermatol.  2016;175(6):1387- 1390. DOI: 10.1111/bjd.14722. PMID: 27233640. 7. Doche I, Coelho EQ, Quaresma MV, da Matta Rivitti-Machado MC. Acne keloidalis nuchae and folliculitis decalvans: same pro- cess affecting the follicle or coexisting diseases? A retrospective study. Int J Dermatol. 2019;58(10):e200-e203 DOI: 10.1111 /ijd.14565. PMID: 31241169. 8. Moreno-Arrones OM, Del Campo R, Saceda-Corralo D, et al. Folliculitis decalvans microbiologic signature is specific for dis- ease clinical phenotype. J Am Acad Dermatol. 2021;85(5):1355- 1357. DOI: 10.1016/j.jaad.2020.10.073. PMID: 33144151. In conclusion, this case highlights the possible emergence of new variants within the FDLPPPS, as the occurrence of FD-FFA in a dark phototype. The keloid evolution of FD lesions is possible without an associated acne keloidalis nu- chae in highly pigmented skins. FD and FFA have both a scarring evolution, and trichoscopy allows an early diagno- sis orientation for an urgent management. Further case re- ports are however needed to fully characterize the FDLPPPS spectrum. References 1. Yip L, Barrett TH, Harries MJ. Folliculitis decalvans and lichen planopilaris phenotypic spectrum: a case series of biphasic clin- ical presentation and theories on pathogenesis. Clin Exp Der- matol. 2020;45(1):63-72. DOI: 10.1111/ced.13989. PMID: 31017678. 2. Egger A, Stojadinovic O , Miteva M. Folliculitis Decalvans and Lichen Planopilaris Phenotypic Spectrum-A Series of 7 New Cases With Focus on Histopathology. Am J Dermatopatho.l 2020;42 (3):173-177. DOI: 10.1097/DAD.0000000000001595. PMID: 31855586. 3. Ramos PM, Melo DF, Lemes LR, et al. Folliculitis decal- vans and lichen planopilaris phenotypic spectrum: case