Strategies for Differentiating Hair Loss Disorders from Alopecia Areata

The diagnosis and treatment of different hair loss disorders are considered essential among clinicians in the dermatology field, with such disorders being some of the most visible dermatologic conditions faced by patients.1

Hair loss disorders such as alopecia areata were brought to the forefront at the Dermatology Education Foundation (DERM) 2025 NP/PA CME Conference in Las Vegas. At the meeting, a session titled ‘The Hidden Undercurrent: When Hair Loss Isn’t Alopecia Areata’ was presented by April W. Armstrong, MD, MPH, Professor and Chief of Dermatology at UCLA and Chair Emeritus of the Medical Board of the National Psoriasis Foundation.

Armstrong noted that alopecia areata is a non-scarring, inflammatory hair loss condition with well-demarcated patches, and that it is treatable with topical and systemic options. Armstrong pointed to a set of images during her presentation, highlighting the qualities that distinguish the presence of alopecia areata-related hair loss.

“So in alopecia area, if you look at these 3 images, you'll notice the left hand side you have ‘exclamation point’ hairs, and then what you see is that tapering right at the proximal hair shaft where it enters the scalp,” Armstrong explained. “And that actually represents the inflammatory process that's around the hair follicles, such that you do see that kind of tapering. That's what we consider these exclamation point hairs. So the tapering part is the part that's closer to the scalp, and then you just see some black dots. Sometimes black dots are not necessarily a bad sign. Black dots mean that the hair follicles are still there…Then on the right-hand side, you see a yellow dot. Yellow dots are also not a terrible sign. Yellow dots mean that you still have hair follicles. They have not scarred over.”

The yellow dots, Armstrong noted, are empty hair follicles that are filled with sebum, for example. She added, however, that this is still non-scarring alopecia and that there are a wide variety of treatment options for patients living with alopecia areata, such as oral JAK inhibitors. Tinea capitis, a fungal infection, was also highlighted by Armstrong as a condition with comparable effects on patients’ hair. The latter condition is characterized by scaling and broken hair, treated with oral antifungals and topical ketoconazole.

“You see these scaling patches, and you may see some hair loss in the area, but the scale is quite predominant,” Armstrong said. “The scale represents this increased epidermal turnover. Tinea capitis definitely has a fungal etiology. On the right-hand side, you can see broken hair. You can see patients with black dots, so the hair is broken, but you still see the remaining hair shaft in the hair follicle. They have this black dot appearance. Now you can do a POH scraping of the tinea capitis. Then, when you see that KOH, you will see your fungal hyphae on the left-hand side. And the tinea capitis can actually be caused by a number of different organisms.”

Armstrong noted that a key element to diagnosing tinea capitis is demographics, noting that tinea capitis occurs most commonly in children aged 3 - 10 years.

“It's actually very uncommon to see tinea cavitus in adults,” Armstrong explained. “Tinea capitis typically occurs in pre-pubertal children, and the reason why it's rare in adults is that when you become an adult, you have greater sebum production. Also, there is a change in the local microbiome of the scalp. So with the sebum and the change in the local microbiome of the scalp, it actually does not favor, typically, the development of tinea capitis. Think about your kids who come in with black dots and broken hair, and also the increased endodermal turnover and the scaling. Keep that in the back of your mind as a possible differential for the diagnosis.”

Trichotillomania was also highlighted by Armstrong during the session, though it is distinguished by irregular patches and ‘flame hairs.’ Flame hairs are a type of broken hair residue. This particular condition can be treated via psychotherapy or Selective Serotonin Reuptake Inhibitors (SSRIs).

“I will say probably the macroscopic appearance of irregularly shaped hatch is a good clue,” Armstrong said. “First, before looking at dermoscopy for this, for trichotillomania, we want to think about psychotherapy for our patients. If you feel comfortable, you want to maybe discuss with the patients, think about SSRIs, and so forth. But oftentimes it can be a difficult discussion, and I oftentimes collaborate with my colleagues in psychiatry if the patient is amenable, to help address this.”

Discoid lupus and lichen planopilaris (LPP) were also discussed as scarring alopecias, with treatments including hydroxychloroquine and JAK inhibitors. Telogen effluvium and androgenetic alopecia were also covered in Armstrong’s presentation, with the presenter emphasizing the importance of accurate diagnosis and tailored treatments.

“There's a laundry list of all the things that can trigger [telogen effluvium], oftentimes physical, and sometimes significant emotional stress, and sometimes changing medication,” Armstrong explained. “To think about the diagnosis of telogen effluvium, you want to consider the hair pull test. This is where you gather about 50 - 60 hairs. If you're not sure how many is 50 - 60 hairs, the first few times you may kind of have to count them out…You want to do a little bit from the occipital area, the frontal area, and then you want to exert firm pressure on it…If you get a few hairs or fewer coming out, that's considered a negative test. But if you get more in that test, you may want to work a little bit more for telogen effluvium. You want to get a positive hair pull test.”

For more on topics related to those highlighted in this session, view the latest conference coverage.

The quotes contained in this session summary were edited for the purposes of clarity.

Armstrong has served as a research investigator, scientific advisor, or speaker to AbbVie, Arcutis, BI, BMS, Leo, UCB, Janssen, Lilly, Novartis, Ortho, Sun, Dermavant, Sanofi, Takeda, Regeneron, and Pfizer.

References

1. Armstrong, A. The Hidden Undercurrent: When Hair Loss Isn’t Alopecia Areata. Presented at DERM 2025 NP PA CME Conference; July 23-26, 2025; Las Vegas, Nevada.