Background
Wegener's granulomatosis (WG) is a rare idiopathic disease in which small and medium-sized arteries are affected by necrotizing granulomatous inflammation. It is associated with a triad of pulmonary (cavitating granulomatous lesions with hemoptysis, cough, and dyspnea), renal (glomerulonephritis with hematuria, proteinuria), and head (otitis media, recurrent sinusitis, eye or orbital involvement) manifestations.
Material and Method
Four children aged 7-11 years diagnosed with WG between 1995-2008 initially presented with unilateral proptosis and ptosis due to orbital tumor. CT or MRI, orbital lesion biopsy, and laboratory tests (ERS, CRP, ANCA) were part of the diagnostic workup. The diagnoses were based on correlation between clinical presentation and diagnostic findings. All four patients had orbital lesions on contrast-enhanced CT and MRI. Two had lesions of the temporal pyramid. Orbital tumor biopsies showed granulomatous lesions in two patients, necrotizing vasculitis with leukocytoclasia in three, and an orbital pseudotumor in one. ESR and CRP were positive in all. ANCA positivity was variable (c-ANCA did not allow WG diagnosis or there were atypical ANCAs). All had blood and protein in the urine, but only one had advanced renal involvement. All were treated with oral steroid and immunosuppression; remission was successful.
Results

Conclusions
WG is often more difficult to diagnose in children than in adults due to frequent absence of its signature features. The absence of the classic triad and atypical laboratory or biopsy findings do not exclude a diagnosis of WG. Orbital demonstration helps achieve early diagnosis and treatment of this potentially fatal rheumatologic disease.

Keywords: Tomography, X-Ray Computed, Orbital Neoplasms - radiography, Contrast Media, Child, Wegener Granulomatosis - pathology