Rare central nervous system manifestation of granulomatosis with polyangiitis in a 12-year-old child: A case report.

To share a unique case of granulomatosis with polyangiitis (GPA) identified in a child with CNS involvement, specifically PRES (posterior reversible encephalopathy syndrome). Discuss this uncommon manifestation's clinical characteristics, diagnostic process, and treatment. We are currently discussing a 12-year-old female patient who presented with a chronic cough, shortness of breath, and a new-onset fever. Upon further examination, the patient was diagnosed with GPA, confirmed through positive cytoplasmic antineutrophil cytoplasmic antibodies (C-ANCA), a renal biopsy, and multiple lung cavitary lesions. During her hospitalization, the patient also experienced neurological symptoms, including a severe headache, blurred vision, loss of consciousness, and an abnormal neurological exam, which led to brain MR imaging. The imaging revealed evidence of small vessel vasculitis with confluent T2 hyper signal intensity of gray-white matter junctions in both parietooccipital and frontal lobes containing hemorrhagic components, suggesting Posterior reversible encephalopathy syndrome. This case of Wegener's granulomatosis is noteworthy due to its occurrence in a pediatric patient with CNS involvement, specifically (posterior reversible encephalopathy syndrome). This event highlights the importance of recognizing that autoimmune disorders can present infrequently in young patients. Diagnosing Wegener's granulomatosis can be challenging, particularly when the CNS is affected. However, when appropriate treatment is initiated promptly, favorable outcomes can be achieved, as evidenced by the patient's improved condition with the prednisolone, captopril, and Rituximab treatment plan. Further research is necessary to understand better the underlying pathophysiology and optimal management of CNS involvement in GPA, particularly in the pediatric population.