Background: Microscopic polyangiitis (mPA) is one of the ANCA-associated primary systemic vasculitides. It is defined as necrotic vasculitis without granuloma development and without minimal immuno-depots in situ. The clinical picture is characterised by destruction of the small vessels with the main manifestations in the upper and lower respiratory tract, in the lungs and kidneys. The eye manifestations were noted yet not so often.
Patient: There were 2 clinical cases, aged 5-12 years, with primary eye manifestations of the mPA. The initial oedema and the reddening of the lid area were common to all the patients. The diagnostic excisions of the inflammatory tumour of the anterior orbital area have shown histologically vasculitis of the small vessels. mPA was diagnosed by clinical and immunological parameters, including the examination of the respiratory tract and kidneys.
Conclusions: In inflammatory orbital pseudotumour, diagnostic excision and evaluation of the immunological parameters are useful for the exclusion of a systemic vasculitis. Proper examinations must be performed to determine other possible organ manifestations. Prognosis is characterised by the severity of kidney involvement. Early immunosuppressive therapy is crucially important for survival prognosis.