Diagnosis, treatment, and long-term outcomes of pediatric pemphigus: a retrospective study at tertiary medical centers

BACKGROUND: Pediatric pemphigus is a rare bullous disease that represents a diagnostic and therapeutic challenge; evidence on patients' response to various treatments and long-term surveillance data are lacking. We aimed to investigate pediatric pemphigus patients' characteristics, diagnosis, therapeutics, response, and long-term follow-up.

METHODS: This is a retrospective study of all pemphigus patients aged <18 years, diagnosed between 2000 and 2023, from three tertiary medical centers in Israel. The diagnosis was confirmed by positive immunofluorescence.

RESULTS: Twelve pediatric pemphigus patients were included (mean age 10.7 ± 4.3 years, male:female ratio 1:1). Mean diagnostic delay was 11.1 ± 12.6 months (range 1.8-36 months). Most patients had pemphigus vulgaris with mucosal involvement (58.3%). First-line treatment for all patients included systemic corticosteroids (sCS), with a treatment duration (including tapering down) of 28 ± 18.4 months. Hospitalization did not yield better outcomes. Only three patients achieved sustained complete response with sCS treatment (25.0%), and the rest required additional therapeutics, most commonly rituximab. Rituximab showed a good safety profile and therapeutic response. Follow-up was recorded up to 18.1 years after diagnosis (mean: 5.6 years). Three of five patients with information available more than 5 years after the pemphigus diagnosis still exhibited disease symptoms.

CONCLUSIONS: Pediatric pemphigus is associated with a significant diagnostic delay. While sCS can induce remission in most patients as a first-line treatment, long-term disease control requires additional immunomodulators. Long-term follow-up reveals a chronic yet mostly benign disease course in this population and advocates for the use of rituximab in pediatric pemphigus patients.