Post-Facial Hyperpigmentation in Fitzpatrick Type IV Skin
A 34-year-old woman with Fitzpatrick skin type IV returns 10 days after a facial at your salon. The service included 20 minutes of steam, manual extractions with a metal comedone extractor, and a 20% glycolic acid peel left on for 10 minutes. She now has symmetric dark brown patches over both cheeks and along the jawline; the skin is smooth, not raised, and she denies blistering or crusting. She used a broad-spectrum SPF 15 only on the day of the facial and spent two afternoons gardening without reapplying. She wants another peel next week because the “brown spots are worse than the acne.” She is not pregnant, not on hydroquinone, and takes no photosensitizing medications. She has no personal history of melasma, but her mother has it. She is otherwise healthy and has no history of keloids.
1. Explain the most likely cause of the pigmentation using skin anatomy and histology; name the cells and layer involved and why her skin type increases risk.
Read the worked answer
The pattern is most consistent with post-inflammatory hyperpigmentation (PIH) triggered by the steam, extractions, and acid peel, then worsened by ultraviolet exposure. Melanocytes reside in the stratum basale at the dermal–epidermal junction. Inflammation and mechanical trauma stimulate melanogenesis; melanosomes are transferred to surrounding keratinocytes and can persist as the epidermis turns over. In epidermal PIH the pigment is in the epidermis and may fade over weeks to months; if pigment drops into the dermis, it can appear gray-brown and last much longer. Fitzpatrick type IV skin has more active melanocytes and a greater tendency to produce pigment after injury than type I or II skin. Her use of only SPF 15 and unprotected gardening allowed UV to stimulate those melanocytes further. This is a reasoning-based explanation, not a diagnosis of melasma; the symmetric distribution and family history mean melasma should be considered, but the recent inflammatory treatment makes PIH the leading explanation.
2. Was the treatment plan appropriate for her? Identify the steps that increased risk.
Read the worked answer
The plan was too aggressive for her skin type and history. Twenty minutes of steam plus manual extractions creates inflammation, and a 20% glycolic peel adds a chemical insult; combining mechanical and chemical trauma in one session raises the risk of PIH. The peel’s concentration, pH, and contact time determine its aggressiveness, and 10 minutes may have been too long for a first-time acid client with type IV skin. The esthetician also failed to give adequate photoprotection instructions and failed to reassess before adding more trauma. A safer approach would have been a single modality, a shorter contact time, a patch test, and a discussion of pigment risk before treatment. The fact that she did not blister does not mean the treatment was appropriate; PIH can occur without blistering. Another peel next week would compound inflammation and should be refused until the pigment settles.
3. Outline a safe plan for the next 8–12 weeks, including ingredients and referral triggers.
Read the worked answer
Do not perform another peel now. Focus on barrier repair and photoprotection: a gentle non-foaming cleanser, a bland moisturizer, and a broad-spectrum SPF 30 or higher applied every morning and reapplied every two hours with outdoor exposure. Recommend non-irritating brightening ingredients such as niacinamide, azelaic acid, or vitamin C, introduced one at a time with a patch test; avoid hydroquinone unless a physician prescribes it. Avoid steam, hot towels, extractions, scrubs, and high-concentration acids until the pigmentation has stabilized. Reassess in 4–6 weeks. Refer to a dermatologist if the pigmentation is grayish, persists beyond 6–12 months, worsens despite sun protection, or if melasma is suspected; also refer if there is any blistering, crusting, or spreading. Document the original treatment, the current findings, the advice given, and the refusal of another peel, because the client may expect rapid results and needs realistic expectations.