Multicenter Study Sheds Light on Pediatric MMP

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Mucous membrane pemphigoid (MMP) is a rare, chronic autoimmune blistering disorder primarily affecting mucosal surfaces. While well-documented in adults, researchers noted MMP in pediatric populations remains poorly characterized.¹ To address this unmet need, a recent multicenter study aimed to delineate the clinical presentation, diagnostic methods, treatment approaches, and outcomes of childhood-onset MMP.²

“MMP is rarely described and poorly understood in children,” researchers behind the study wrote. “Our study provides a better characterization of this rare and clinically polymorphous disease, which is still misdiagnosed too frequently and whose treatment is unfortunately delayed, but which is potentially serious in children.”

Background

MMP is an autoimmune disease characterized by subepithelial blistering and scarring of mucous membranes, including the oral, ocular, and anogenital mucosa. The condition is caused by autoantibodies targeting components of the basement membrane zone, leading to inflammatory destruction. While most cases are reported in adults, pediatric MMP is rare, and data regarding its clinical course, diagnostic challenges, and treatment efficacy remain limited.1 This study investigates childhood MMP through a comprehensive multicenter approach.

Methods

A retrospective analysis was conducted using data from multiple dermatology and immunology centers. Pediatric patients diagnosed with MMP were included based on clinical features, histopathological findings, and direct immunofluorescence (DIF) testing. Demographic data, mucosal involvement, treatment regimens, and long-term outcomes were documented.

Results

Demographics and Clinical Presentation

Among the pediatric patients included, the mean age at diagnosis was early adolescence. No significant gender predominance was observed. The most frequently affected site was the oral mucosa, followed by the ocular and anogenital regions. Cutaneous involvement was rare but present in a minority of cases.

Diagnostic Findings

Histopathology consistently revealed subepidermal blistering with an inflammatory infiltrate, confirming an autoimmune etiology. DIF testing demonstrated linear deposits of IgG, IgA, and/or C3 at the basement membrane zone, serving as a key diagnostic criterion. Indirect immunofluorescence and enzyme-linked immunosorbent assay (ELISA) tests further identified circulating autoantibodies in some cases.

Treatment and Outcomes

Systemic corticosteroids were the primary treatment modality, often combined with steroid-sparing immunosuppressants such as dapsone, azathioprine, or mycophenolate mofetil. In refractory cases, biologic agents, including rituximab, were utilized. Long-term follow-up indicated that while some patients achieved remission, others required ongoing therapy to control disease progression. Ocular involvement was associated with a higher risk of complications, including vision impairment.

Discussion

This study highlights the clinical heterogeneity of pediatric MMP and underscores the challenges in diagnosis and management. The predominance of oral mucosal lesions suggests that pediatric MMP may initially be mistaken for more common oral conditions, leading to diagnostic delays. Researchers stated DIF remains the gold standard for diagnosis, and early identification is crucial to prevent severe complications, particularly ocular scarring.

Treatment responses varied among patients, with a need for prolonged immunosuppressive therapy in severe cases. The study also reinforces the importance of a multidisciplinary approach involving dermatologists, ophthalmologists, and pediatric specialists to optimize patient care. Researchers suggested future research should focus on identifying biomarkers for early detection and developing targeted therapies to minimize adverse effects in pediatric patients.

Conclusion

The study stated that childhood-onset MMP is a rare but serious condition that requires early recognition and aggressive treatment to prevent long-term morbidity. The multicenter analysis provides valuable insights into its clinical spectrum, diagnostic strategies, and therapeutic outcomes, emphasizing the need for continued research and improved management protocols, especially in pediatric patients.

References

1. Chan LS, Ahmed AR, Anhalt GJ, et al. The first international consensus on mucous membrane pemphigoid: definition, diagnostic criteria, pathogenic factors, medical treatment, and prognostic indicators. Arch Dermatol. 2002;138(3):370-379. doi:10.1001/archderm.138.3.370
2. Chêne L, Le Roux-Villet C, Martin L, et al. Characterization of mucous membrane pemphigoid in childhood: A multicentre study of 12 cases. J EurAcad Dermatol Venereol. Published online March 29, 2025. doi:10.1111/jdv.20675