Classic Pseudopelade of Brocq
Classic pseudopelade of Brocq (POB) is a rare, slowly progressive primary lymphocytic cicatricial alopecia. It produces small, ivory-white or pale pink atrophic bald patches in which the follicular openings are completely lost, without any obvious clinical inflammation. It was first described in 1888 by the French dermatologist Louis-Anne-Jean Brocq. The name "pseudopelade" reflects the fact that early lesions look very much like alopecia areata (pelade in French), yet they end in scarring and permanent hair loss.
How pseudopelade of Brocq develops is still debated, with two main schools of thought:
- A distinct idiopathic autoimmune disease: In this view, POB is a separate scalp disorder. CD4+ and CD8+ T cells slowly and silently attack the follicular bulge, where hair follicle stem cells reside. Because the reaction stays below the threshold of visible acute inflammation (no obvious redness or scaling), the stem cells quietly degenerate and the follicles shrink and are replaced by fibrous tissue without the patient noticing.
- A burned-out, end-stage phenomenon: Many dermatologists believe POB is not a separate disease but the late, inflammation-free stage of other lymphocytic scarring alopecias, particularly lichen planopilaris (LPP) or subtle discoid lupus erythematosus (DLE).
- Sebaceous gland loss and columnar fibrosis: The disease destroys the sebaceous glands early, damages the basement membrane around the follicle and stimulates fibroblasts, so that vertical fibrous tracts of collagen take the place of the original follicles.
At Haute-Derma, caring for patients with pseudopelade of Brocq calls for careful differential diagnosis to determine whether low-grade inflammation is still active or the disease has moved into a fully scarred stage.
Clinical Features and Differential Diagnosis
Classic pseudopelade of Brocq has distinctive clinical features, often described with some of dermatology's best-known images:
- "Footprints in the snow": Small, irregular bald patches from a few millimeters to 1–2 cm across, ivory-white or pale pink. Many small patches are scattered across the scalp and gradually merge into larger areas with wavy borders, like footprints left in fresh snow.
- Soft, slightly atrophic, smooth scalp: The bald skin has completely lost its follicular openings (follicular ostia). It feels smooth and, when pressed, slightly depressed and softer than the surrounding healthy skin (because the follicles and sebaceous glands beneath have disappeared).
- Silent progression without signs of inflammation: There is no thick scale around the follicles, no obvious violaceous rim and no pustules. Patients feel no pain and no itch (asymptomatic) and often discover the patches by chance while brushing their hair or when someone else points them out.
- Trichoscopy (scalp dermoscopy) findings:
- Complete loss of follicular openings on a milky-white or ivory-pink background.
- No perifollicular casts, an important difference from active LPP.
- "Lonely hairs": A few isolated hairs left standing in the middle of an atrophic scar.
Our Approach to Diagnosis and Treatment at Haute-Derma
- Imaging, Histopathology and DIF: Trichoscopy is used to assess the full extent of hair loss. A 4 mm scalp punch biopsy is taken from the edge of a bald patch:
- H&E staining: Complete loss of sebaceous glands, with vertical fibrous tracts replacing the follicles. Lymphocytic inflammation is minimal or absent altogether (a late-stage picture).
- Direct immunofluorescence (DIF): Negative, which helps rule out discoid lupus erythematosus (DLE).
- Medical Treatment to Stop Low-Grade Inflammation: Although POB progresses very slowly, if the disease is still active (bald patches continue to spread), medical treatment is essential to protect the remaining follicles:
- Hydroxychloroquine (HCQ): The first-line option to modulate the immune response and halt hair loss (dose ≤ 5 mg/kg/day).
- High-potency topical or intralesional corticosteroids (ILTAC): Low-concentration triamcinolone acetonide (2.5–5 mg/mL) injected along the advancing edge of hair loss.
- Topical calcineurin inhibitor (tacrolimus 0.1%): Helps control microscopic inflammation at the margins without causing further skin atrophy.
- Mycophenolate mofetil / JAK inhibitors: Reserved for rapidly progressive POB or cases that do not respond to standard therapy.
- Cosmetic and Hair Restoration Options: Unlike scarring alopecias caused by pustules or bacteria (which usually leave thick, hard, poorly nourished scars), POB scars are relatively soft and keep reasonably good microcirculation. Once the disease has been completely inactive (burned-out phase) for at least 12–24 months:
- We assess suitability for autologous hair transplantation (FUE/FUT) into POB scars, where graft survival is relatively encouraging.
- We offer scalp micropigmentation (SMP) to camouflage small scarred patches and give a natural-looking result.
Pseudopelade of Brocq vs. Other Types of Hair Loss
| Pseudopelade of Brocq (POB) | Alopecia Areata | Lichen Planopilaris (LPP) |
|---|---|---|
| Scarring alopecia (follicular openings lost). | Non-scarring alopecia (follicular openings preserved). | Scarring alopecia (follicular openings lost). |
| "Footprints in the snow", ivory-white, mildly atrophic. | Smooth round or oval patches, normal skin color. | Bald patches with a red/violaceous rim and perifollicular scale. |
| No pain, no itch. | No pain, no itch. | Burning, stinging, intense itch (trichodynia). |
| Loss of follicular openings, lonely hairs. | Yellow dots, black dots, exclamation-mark hairs. | Tubular perifollicular casts around the hair shafts. |
| Hair cannot regrow in scarred areas. | Hair can regrow completely. | Hair cannot regrow in scarred areas. |
