Folliculitis decalvans microbiological signature is specific for disease clinical phenotype

Clinical Characterization and Treatment Response of Folliculitis Decalvans Lichen Planopilaris Phenotypic Spectrum: A Unicentre Retrospective Series of 31 Patients

Folliculitis decalvans and lichen planopilaris phenotypic spectrum has been described as a form of cicatricial alopecia. The aim of this study is to describe the clinical and trichoscopic features and therapeutic management of this condition in a series of patients. A retrospective observational unicentre study was designed including patients with folliculitis decalvans and lichen planopilaris phenotypic spectrum confirmed with biopsy. A total of 31 patients (20 females) were included. The most common presentation was an isolated plaque of alopecia (61.3%) in the vertex. Trichoscopy revealed hair tufting with perifollicular white scaling in all cases. The duration of the condition was the only factor associated with large plaques (grade III) of alopecia (p = 0.026). The mean time to transition from the classic presentation of folliculitis decalvans to folliculitis decalvans and lichen planopilaris phenotypic spectrum was 5.2 years. The most frequently used treatments were topical steroids (80.6%), intralesional steroids (64.5%) and topical antibiotics (32.3%). Nine clinical relapses were detected after a mean time of 18 months (range 12-23 months). Folliculitis decalvans and lichen planopilaris phenotypic spectrum is an infrequent, but probably underdiagnosed, cicatricial alopecia. Treatment with anti-inflammatory drugs used for lichen planopilaris may be an adequate approach.

Diagnoseverzögerung, komorbide Hidradenitis suppurativa und die prognostische Bedeutung bakterieller Kulturen bei Folliculitis decalvans: eine Kohortenstudie

Hintergrund

Folliculitis decalvans (FD) ist eine primäre neutrophile vernarbende Alopezie, die häufig zu irreversiblem Haarverlust führt. Daten zu Epidemiologie, klinischen Merkmalen, Folgen und prognostischen Faktoren sind nur eingeschränkt verfügbar.

Ziel

Die Beurteilung einer Patientenkohorte mit FD sowie die Charakterisierung schwerer Krankheitsverläufe und prognostischer Faktoren, die eine Remission verhindern.

Patienten und Methoden

Diese retrospektive Kohortenstudie umfasste 192 Patienten, bei denen zwischen 2010 und 2020 an einem tertiären Zentrum eine FD diagnostiziert und die mindestens sechs Monate nachverfolgt wurden.

Ergebnisse

Die Diagnose wurde im Mittel um 22,2 (± 29,7) Monate verzögert gestellt. Komorbide Erkrankungen mit Okklusion der Haarfollikel waren häufig. In 45,6% der Fälle waren Bakterienkulturen positiv, am häufigsten mit Staphylococcus (S.) aureus. Schwere Krankheitsverläufe waren mit komorbider Hidradenitis suppurativa und positiver Bakterienkultur, insbesondere S. aureus, assoziiert. Bei 50,7% der Patienten kam es zu vollständiger Remission: Bei 32% innerhalb der ersten sechs Monate der Behandlung und bei 18,7% während der Nachkontrolle. Rezidive waren häufig. Negative Prognosefaktoren bezüglich der Remission waren jüngeres Alter und positive Bakterienkultur.

Schlussfolgerungen

Es besteht Bedarf hinsichtlich der Ausbildung von Dermatologen, um die Diagnoseverzögerung zu reduzieren. Das Screening von FD‐Patienten auf komorbide Hidradenitis suppurativa und Bakterienkulturen sind wichtig für die Behandlungsplanung.

Diagnostic delay, comorbid hidradenitis suppurativa and the prognostic value of bacterial culture in folliculitis decalvans: A cohort study

BACKGROUND

Folliculitis decalvans (FD) is a type of primary neutrophilic cicatricial alopecia often leading to irreversible hair loss. Data on its epidemiology, clinical features, outcomes, and prognostic factors are limited.

OBJECTIVE

To evaluate a cohort of patients with FD and identify characteristics of severe disease and prognostic factors which impede remission.

PATIENTS AND METHODS

This retrospective cohort study included 192 patients diagnosed with FD and followed for at least six months at a tertiary center between 2010 and 2020.

RESULTS

There was a diagnostic delay averaging 22.2 (± 29.7) months. Comorbid follicular occlusion disorders were common. Bacterial cultures were positive in 45.6% of the cases, with Staphylococcus (S.) aureus being the most common pathogen. Severe disease was associated with comorbid hidradenitis suppurativa and a positive bacterial culture, particularly S. aureus. 50.7% of patients experienced complete remission: 32% within the first six months of treatment and 18.7% later during follow-up. Relapses were frequent. Negative prognostic factors for achieving remission included younger age and a positive bacterial culture.

CONCLUSIONS

There is a need for the education of dermatologists to reduce the diagnostic delay. Screening FD patients for comorbid hidradenitis suppurativa and obtaining bacterial cultures is important for treatment planning.

Folliculitis decalvans and dystrophic epidermolysis bullosa: a significant association

This work reports 30 cases of folliculitis decalvans (FD) in patients with dystrophic epidermolysis bullosa (DEB) among a cohort of 125 DEB patients seen between 2010 and 2021 in 2 French expert centers for the management of inherited epidermolysis bullosa. Such an association between two rare diseases cannot be fortuitous and implies a physiopathological link that we discuss in this paper. This association is a new significant fact to add to the reflexion on FD causes, suggesting that skin abnormality of DEB could act as a factor of a specific skin barrier alteration which could favor FD. Scarring alopecia with tufted folliculitis and pustules on inflamed skin at the vertex of a woman with dominant dystrophic epidermolysis bullosa.

Folliculitis Decalvans and Lichen Planopilaris Phenotypic Spectrum: A Case Report

The folliculitis decalvans (FD) and lichen planopilaris (LPP) phenotypic spectrum combines biphasic features of FD and LPP. It is characterized by successive or concomitant occurrence of pustules, crusts, follicular tufts, perifollicular erythema, perifollicular scales, and cicatricial alopecia and includes mixed histologic features of both FD and LPP. Here, we report the case of a 33-year-old female patient with a 30-year history of FD-LPP phenotypic spectrum lesions.

Epidermis as a Platform for Bacterial Transmission

The epidermis constitutes a continuous external layer covering the body, offering protection against bacteria, the most abundant living organisms that come into contact with this barrier. The epidermis is heavily colonized by commensal bacterial organisms that help protect against pathogenic bacteria. The highly regulated and dynamic interaction between the epidermis and commensals involves the host’s production of nutritional factors promoting bacterial growth together to chemical and immunological bacterial inhibitors. Signal trafficking ensures the system’s homeostasis; conditions that favor colonization by pathogens frequently foster commensal growth, thereby increasing the bacterial population size and inducing the skin’s antibacterial response, eliminating the pathogens and re-establishing the normal density of commensals. The microecological conditions of the epidermis favors Gram-positive organisms and are unsuitable for long-term Gram-negative colonization. However, the epidermis acts as the most important host-to-host transmission platform for bacteria, including those that colonize human mucous membranes. Bacteria are frequently shared by relatives, partners, and coworkers. The epidermal bacterial transmission platform of healthcare workers and visitors can contaminate hospitalized patients, eventually contributing to cross-infections. Epidermal transmission occurs mostly via the hands and particularly through fingers. The three-dimensional physical structure of the epidermis, particularly the fingertips, which have frictional ridges, multiplies the possibilities for bacterial adhesion and release. Research into the biology of bacterial transmission via the hands is still in its infancy; however, tribology, the science of interacting surfaces in relative motion, including friction, wear and lubrication, will certainly be an important part of it. Experiments on finger-to-finger transmission of microorganisms have shown significant interindividual differences in the ability to transmit microorganisms, presumably due to genetics, age, sex, and the gland density, which determines the physical, chemical, adhesive, nutritional, and immunological status of the epidermal surface. These studies are needed to optimize interventions and strategies for preventing the hand transmission of microorganisms.