In Pediatric Rheumatology, researchers presented the case study of a patient with pediatric-onset limited antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV) that arose on a background of preexisting chronic recurrent multifocal osteomyelitis (CRMO).
A 13-year-old girl was diagnosed with CRMO after presenting with right foot pain and limping; she also had jaw pain. Magnetic resonance imaging (MRI) of the temporomandibular joints revealed abnormal marrow signaling within the mandible alongside a number of well-defined lesions bilaterally.
A nuclear medicine scan revealed low-level F-fluorodeoxyglucose uptake in both of the patient’s feet and her right elbow. A bone biopsy of the mandibular lesion demonstrated sterile chronic osteomyelitis. She was prescribed naproxen, which was sufficient as analgesia. Her CRMO was under clinical remission.
However, she developed a rising erythrocyte sedimentation rate of 20 to 30 mm/h. This coincided with her developing truncal and forehead lesions that responded well to topical tacrolimus. Skin biopsy results were compatible with pyoderma gangrenosum.
Read more about AAV etiology
She eventually developed right otalgia and acute otitis (that were antibiotic resistant), as well as persistent ear discharge, prompting her physicians to insert a right ear tympanostomy tube and perform left sphenoidotomy. Similar symptoms began to appear in her left ear, accompanied by progressive hearing loss. She also developed sinusitis.
A computed tomography (CT) scan revealed left sphenoid sinusitis, bilateral mastoiditis, and middle ear effusions. Further investigations revealed positivity for cytoplasmic-ANCA and elevated proteinase 3. She was diagnosed with limited granulomatosis with polyangiitis (GPA) acquired during preexisting CRMO and was prescribed rituximab and oral steroids.
These medications resulted in temporary relief but her symptoms returned 6 months after treatment initiation. She was started on oral steroids, rituximab, and azathioprine, which allowed her to achieve adequate disease control. She continues to be followed up at the pediatric rheumatology clinic.
“To our knowledge, our case represents the first in which persistently active CRMO preceded the onset of limited GPA by years,” the authors concluded.
Reference
Eloseily E, Henrickson M. Pediatric-onset limited ANCA-associated vasculitis arising during pre-existing chronic recurrent multifocal osteomyelitis. Pediatr Rheumatol Online J. Published online August 24, 2023. doi:10.1186/s12969-023-00876-x
