CHICAGO – Late dermatologic manifestations in children who have received hematopoietic stem cell transplants may be more common than previously thought, according to results of a new study.
Johanna Song, MD, and her collaborators reported that, in their prospective pediatric study, 25% of patients had permanent alopecia and 16% had psoriasis, noting that late nonmalignant skin effects of hematopoietic stem cell transplantation (HSCT) have been studied primarily retrospectively, and in adults. Vitiligo and nail changes were also seen.
In a poster presentation at the World Congress of Dermatology, Dr. Song and her colleagues noted that these figures are higher than the previously reported pediatric rates of 1.7% for vitiligo and 15.6% for permanent alopecia. “Early recognition of these late effects can facilitate prompt and appropriate treatment, if desired,” they said.
The single-center, cross-sectional cohort study tracked pediatric patients over an 18-month period and included patients who were at least 1 year post allogeneic HSCT and had not relapsed. Patients who were not English speaking were excluded.
The median age of the 85 patients enrolled in the study was 13.8 years, and participants were a median of 3.6 years post transplant at the time of enrollment. The study’s analysis attempted to determine which patient, transplant, and disease factors might be associated with the late nonmalignant skin changes, according to Dr. Song, a resident dermatologist at Harvard University, Boston, and her colleagues.
Most – 52– of the patients (61.2%) had hematologic malignancies; 12 patients (14.1%) received their transplant for bone marrow failure, and 11 patients (12.5%) had immunodeficiency. Three patients (3.5%) received HSCT for other malignancies, and seven (8.2%) for nonmalignant diseases.
Diffuse hair thinning was seen in 13 (62%) of the 21 patients who had alopecia, while 11 (52%) of the patients with alopecia had an androgenetic hair loss pattern. Chronic graft versus host disease (GVHD), skin chronic GVHD, a HSCT regimen that included busulfan conditioning, and a family history of early male-pattern alopecia were all significantly associated with post-HSCT permanent alopecia (P less than .05 for all).
The patients with androgenetic alopecia may be experiencing an accelerated time course of a condition to which they are already genetically disposed, noted Dr. Song and her colleagues.
Psoriasis was commonly seen on the scalp, affecting 11 of the 14 patients with psoriasis (79%), and involved the face in five of the patients (36%). Just one patient had psoriasis elsewhere on the body. There was a nonsignificant trend towards human leukocyte antigen mismatch among patients who had psoriasis. Although “psoriasis may be a marker of persistent immune dysregulation,” the investigators said, they did not identify any associated risk factors that would point toward this mechanism in their analysis.
Twelve patients (14%) had vitiligo, with halo nevi seen in four of these patients. Children who were younger than age 10 years and those who received their transplant for primary immunodeficiency were significantly more likely to have vitiligo (P less than .05 for both). Specific possible mechanisms triggering vitiligo could include thymic dysfunction resulting in loss of self-tolerance, and donor alloreactivity against the patient’s host antigens, according to the authors.
Nail changes such as pterygium and nail pitting, ridging, or thickening were seen in just five patients, all of whom had chronic GVHD of the skin. “Nail changes are likely a result of persistent inflammation and immune dysregulation from chronic GVHD,” said Dr. Song.
These late effects “can significantly impact patients’ quality of life,” according to the authors, who called for larger studies that follow pediatric HSCT patients longitudinally, beginning before the transplant – and for more investigation into the pathogenesis of specific late effects.
Dr. Song reported no relevant conflicts of interest.