In a prospective cohort study published in Journal of the American Academy of Dermatology, researchers described four patterns of hair loss observed in patients with cutaneous chronic graft-versus-host disease. According to their findings, alopecia that occurs in this population may be a manifestation of chronic graft-versus-host disease of the hair follicle.
“These findings suggest that if [chronic graft-versus-host disease] of the hair follicle represents a distinct type of alopecia, revision to the current diagnostic NIH consensus framework should be considered to include new sclerotic or nonscarring alopecia as a diagnostic criterion for [chronic graft-versus-host disease],” Lauren R. Penzi, MD, of the department of dermatology at Massachusetts General Hospital, Boston, and colleagues wrote.
The single-center study included 17 adult allogenic hematopoietic cell transplantation (HCT) recipients who received a diagnosis of cutaneous chronic graft-versus-host disease (cGVHD) at Massachusetts General Hospital in Boston. Two 4 mm punch biopsies of the scalp were performed using hematoxylin-eosin and immunohistochemical stains.
In scalp biopsies from female HCT recipients with male donors, fluorescent in situ hybridization (FISH) analysis was performed for XY chromosomes to identify chimerism and investigate the presence of donor chromosomes in the scalp skin and hair follicle, according to researchers.
The patients included eight women and nine men (combined mean age, 56.1 years). The most frequent indication for HCT was acute myeloid leukemia (58.8%). Most donors (64.7%) were sex-matched and human leukocyte antigen matched.
The average duration of persistent scalp hair loss was 32 months (range, 6 to 87 months). Many patients had patchy nonscarring alopecia (41.2%) or normal hair (29.4%). Other patterns of alopecia included diffuse nonscarring (11.8%), diffuse sclerotic (11.8%) and patchy sclerotic (5.9%).
“In female cGVHD patients who had male HCT donors, FISH studies demonstrated green Y chromosomes within the epidermis of the skin, consistent with their known diagnosis or cutaneous cGVHD,” Penzi and colleagues wrote. “Y chromosomes were also identified at the precise hair follicle location of the inflammatory infiltrate, surrounding the hair bulb in nonscarring alopecia cases and at the hair follicle bulge in sclerotic alopecia, respectively.”
FISH studies in female patients with cGVHD of sex mismatched donors demonstrated green Y chromosomes directly in the inflammatory infiltrate, whether bulb or bulge, on scalp biopsy, according to researchers.
“Of chief importance, this anatomical distribution of Y chromosomes at the respective location of inflammation in the hair follicle bulb or bulge supports the presence of graft-versus-host disease of the hair follicular unit, which has not been previously identified through the use of FISH analysis,” the researchers wrote. – by Abigail Sutton
Disclosures: The authors report no relevant financial disclosures.