Practice Update
Sarah L Chamlin MD
July 23, 2014–Several topics related to pediatric hair loss were discussed at the 40th Annual Meeting of the Society for Pediatric Dermatology, held in Coeur d’Alene, Idaho, July 9th through the 12th, 2014.
Sheila Fallon Friedlander, MD, from the University of California, San Diego, and colleagues presented a poster discussing the prevalence of irreversible alopecia after appropriate pulsed dye laser (PDL) therapy in hair-bearing sites in the pediatric setting. The researchers surveyed pediatric dermatologists at the Society for Pediatric Dermatology biannual meeting held in Denver, Colorado, in 2012, on prevalence of irreversible alopecia after PDL treatment of port-wine stains.
Of the 64 pediatric dermatologists who completed the survey, 50 had used PDL therapy. The majority had used PDL therapy on high-risk areas, including the eyebrow (80%) or scalp (86%). About a quarter of these respondents (25.5%) reported that at least 1 patient developed irreversible alopecia. The researchers reported an incidence of irreversible alopecia after PDL therapy of 1.5% to 2.6%.
The risk for irreversible alopecia at hair-bearing sites after pulsed dye laser therapy is higher than has been previously estimated, and further study is needed to determine risk and contributing factors, the researchers concluded.
“While the exact risk for this complication is unknown, this should be reviewed with families when their infants are being treated with PDL in hair-bearing areas such as the eyebrows or hairline,” noted PracticeUpdate Dermatology editorial board member, Sarah Chamlin, MD.
Elise A. Olsen, MD, of Duke University in Durham, North Carolina, discussed diagnosis and treatment of telogen effluvium, the most common cause of childhood global, diffuse hair loss. Telogen effluvium is characterized by a shift in normal hair activity.1 Normally, hair follicle activity follows a cycle containing four phases: (1) anagen, or growth; (2) catagen, or involution; (3) telogen, or dormancy; and (4) exogen, or release. The average scalp has 86%, 1%, and 13% of hair in each of the first three phases, respectively. In patients with telogen effluvium, 70% of hair is in anagen and 30% is in telogen.
Dr. Olsen pointed to common causes of telogen effluvium, which include: stress; a medical or surgical event; thyroid disease; medications; and nutritional deficiencies of protein, calories, biotin, zinc, or iron.
An abnormal active hair-pull test consists of three to four telogen hairs. Patient laboratory evaluation may consist of a complete blood count with differential, thyroid-stimulating hormone measurement, T4, ferritin, and total iron-binding capacity. If a diet-related cause is assumed, fasting levels of zinc and biotin may be included in the lab. Vitamins should be withheld for 3 days prior to obtaining laboratory studies for vitamin levels, Dr. Olsen noted. The differential diagnosis of diffuse hair loss includes diffuse alopecia areata, loose anagen syndrome, short anagen syndrome, and androgenetic alopecia.
Childhood vitiligo was discussed by Pearl E. Grimes, MD, of the Vitiligo and Pigmentation Institute of Southern California, in Los Angeles. Vitiligo is an acquired cutaneous achromia in which peripheral enlargement of milky white cutaneous macules is observed.2
Dr. Grimes discussed three considerations that should be made in the pediatric population, which accounts for close to a quarter of vitiligo patients. First, providers should consider obtaining a thyroid panel and thyroid antibodies in pediatric patients. While the reported prevalence of thyroid disease in this population widely varies, there is an increased risk in children and an increased frequency of first- and second-degree relatives with autoimmune disease.
Secondly, providers should also consider multivitamins, omega-3 eicosapentaenoic acid, and vitamins C and D as supplements due to the presence of oxidative stress, although according to Robert Brodell, MD, Editor-in-Chief of PracticeUpdate Dermatology, “data confirming the benefits of these treatments are not available, although it is important to remain optimistic.” Finally, providers should measure antinuclear antibody levels before beginning narrow-band UVB phototherapy, which can be used to stabilize rapidly progressive and disseminated vitiligo.
References
Grover C, Khurana A. Telogen effluvium. Indian J Dermatol Venereol Leprol. 2013;79(5):591-603.