結節性多発動脈炎

Pustulotic arthro-osteitis (PAO) is a chronic inflammatory disorder associated with palmoplantar pustulosis (PPP) and characterized by osteoarticular manifestations. Although several immune-mediated comorbidities have been reported in association with PPP/PAO, polyarteritis nodosa (PAN) occurring in patients with PPP/PAO has not been described previously. We report a 56-year-old woman with a long-standing history of PPP and PAO who developed worsening osteoarticular symptoms in close temporal proximity to purpura, lower-extremity pain, and sensory disturbance, followed by paresthesia in the fingers. Neurological examination revealed mild weakness of the left tibialis anterior muscle. Laboratory testing showed elevated inflammatory markers, whereas myeloperoxidase- and proteinase 3-antineutrophil cytoplasmic antibodies were negative. Musculoskeletal imaging revealed bilateral sternoclavicular joint synovitis, inflammatory changes adjacent to the right patellar tendon insertion with infrapatellar bursitis, and right peroneal tenosynovitis. Nerve conduction studies in the lower extremities suggested mononeuritis multiplex. Skin biopsy of a purpuric lesion demonstrated fibrinoid necrosis and inflammatory infiltration in medium-sized arteries within the subcutaneous tissue. The patient was diagnosed with exacerbation of PAO complicated by PAN and was treated with oral prednisolone followed by methotrexate, resulting in rapid normalization of inflammatory markers and improvement in osteoarticular symptoms, purpura, and finger paresthesia, although lower-extremity neurological symptoms persisted at discharge. When patients with PAO develop atypical features such as purpura or neuropathic symptoms suggestive of mononeuritis multiplex, concomitant vasculitis, including PAN, should be considered in the differential diagnosis.

PURPOSE: To report cilioretinal-sparing central retinal artery occlusion (CRAO) in a child with adenosine deaminase 2 (ADA2) deficiency and polyarteritis nodosa-like systemic vasculitis. METHODS: This retrospective case report was based on clinical records, retinal imaging, automated visual field testing, systemic evaluation, and genetic testing. RESULTS: An 11-year-old girl first presented with intermittent exotropia and a normal fundus. Eight months later, she developed fever, weight loss, post-prandial abdominal pain, vasculitic rash, and hypertensive urgency. Her elder brother was also diagnosed with severe hypertension. Skin biopsy revealed medium-vessel vasculitis, raising suspicion for monogenic polyarteritis nodosa-like vasculitis. ADA2 testing was initiated, and she began treatment with oral prednisolone and azathioprine. Twelve months after her initial ophthalmic visit, she maintained best-corrected visual acuity of 20/20 in both eyes but showed a neuroretinitis-like appearance in the left eye, including subtle optic disc margin blurring, sectoral retinal whitening, perivascular sheathing, and peripapillary exudation. One week later, she reported a grey central field disturbance. Visual acuity remained 20/20, but automated perimetry revealed a dense paracentral scotoma. At this time, genetic testing confirmed a homozygous pathogenic ADA2 variant in both siblings. Fundus examination and optical coherence tomography identified CRAO with cilioretinal artery territory sparing. She was treated with intravenous methylprednisolone, blood pressure management, and adalimumab. At 6 months, visual acuity remained stable, with persistent paracentral field loss and structural sequelae of CRAO. CONCLUSION: ADA2 deficiency should be considered in children with retinal arterial occlusion, especially when systemic vasculitis, severe hypertension, or sibling involvement is present.

We report two pediatric cases of macular arteritis presenting as asymptomatic retiform pigmented macules on the legs. Biopsy showed deep dermal-subcutaneous lymphocytic arteritis with fibrin deposition and luminal narrowing, with a negative infectious and autoimmune workup. Both patients remained well with stable lesions at 1 and 7 years of follow-up. These cases add to the limited pediatric literature and support macular arteritis as an infrequent benign cutaneous arteritis, helping avoid unnecessary investigations and aggressive treatment.

Vasculitis encompasses a heterogeneous group of diseases characterized by the inflammation of blood vessels. In children, the diagnosis of vasculitis with cutaneous involvement relies on a combination of clinical evaluation, histopathological examination, and, in some cases, genetic investigations. Diagnosing pediatric vasculitis remains particularly challenging due to overlapping clinical manifestations, variable disease courses, and the evolving nature of histological features. Histopathological assessment aims to confirm inflammation of the vessel walls-either readily visible at low magnification or requiring serial sections-and to characterize the inflammatory infiltrate and other key features that aid in classifying the vasculitis subtype. Accurate diagnosis requires ongoing dialog and collaboration among multiple specialists. In this article, we present the clinical and histopathological features of the most common pediatric vasculitides-including IgA vasculitis and polyarteritis nodosa-as well as newly recognized entities such as COVID-19-associated vasculitis and monogenic vasculitides.