Expanding the Phenotype of OTUD6B-Related Disorder: Neurodevelopmental Impairment and Immune Dysregulation with Immune Thrombocytopenic Purpura: A Case Report

Main Article Content

Lilyan Jarrar
Ahmad Mashni
Raya Fuqha
Mahdi Zaid

Abstract

Background: OTUD6B-related disorder is a rare autosomal recessive condition primarily associated with neurodevelopmental impairment, seizures, and dysmorphic features. Its possible role in immune dysregulation has not been well documented.


Case Presentation: We describe an 11-year-old Palestinian female with a homozygous OTUD6B (c.173-2A>G) mutation who presented with global developmental delay, cavovarus foot deformities, scoliosis, seizures, and recurrent infections. During hospitalization, she developed severe thrombocytopenia (platelet count 8,000/µL) with epistaxis, hematemesis, and a purpuric rash. Laboratory evaluation confirmed immune thrombocytopenic purpura (ITP). She responded to intravenous immunoglobulin (1 g/kg, total dose 18 g), methylprednisolone, and supportive care, with platelet recovery to 17,000/µL within 24 hours. Her younger sister, also carrying the same OTUD6B mutation, exhibited developmental delay and seizures but no hematologic complications.


Discussion: This case suggests a potential novel association between OTUD6B mutations and immune dysfunction, particularly ITP. The observation expands the clinical spectrum of OTUD6B-related disorders beyond neurodevelopmental impairment, raising the possibility of immune dysregulation through disrupted deubiquitination pathways and type I interferon signaling.


Conclusion: Recognition of hematologic manifestations in OTUD6B-related disorder is essential for comprehensive patient management and genetic counseling. Further research is needed to clarify the immunological role of OTUD6B and its contribution to autoimmune conditions.

Article Details

Jarrar, L., Mashni, A., Fuqha, R., & Zaid, M. (2025). Expanding the Phenotype of OTUD6B-Related Disorder: Neurodevelopmental Impairment and Immune Dysregulation with Immune Thrombocytopenic Purpura: A Case Report. Archives of Case Reports, 286–291. https://doi.org/10.29328/journal.acr.1001161
Case Reports

Copyright (c) 2025 Jarrar L, et al.

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This work is licensed under a Creative Commons Attribution 4.0 International License.

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