IgG4-related disease with renal and orbital involvement: a clinical case.

INTRODUCTION: IgG4-related disease (IgG4-RD) is characterized by the growth of pseudotumors, which can affect almost every organ. Elevated serum IgG4 levels are present in only two-thirds of the patients and are not specific. Diagnosis is difficult and is usually based on a biopsy. CLINICAL CASE: A 39-year-old man presented complaints of low back pain and fever. A renal computed tomography (CT) scan revealed a voluminous mass next to the right kidney and a biopsy showed an inflammatory process and excluded a neoplasm. A follow-up CT scan at four months revealed total regression without any treatment. Three years later, the patient presented with diplopia and right proptosis. MRI of the orbits revealed a retro-ocular mass; biopsy excluded a malignant process. Infectious, autoimmune or paraneoplastic diseases were also excluded. Although the patient's IgG4 serum levels were normal, histopathological reobservation of the renal biopsy revealed IgG4-positive plasma cells, thus confirming the diagnosis. The patient was prescribed a daily dose of 40 mg of prednisolone and regression of the right orbital lesion was observed. DISCUSSION: IgG4-RD is a rare and recently described condition. Most anatomic pathology laboratories do not routinely test for it. Spontaneous pseudotumor remission is possible, even when associated with the renal phenotype, although this has not been described until now.

Takayasu Arteritis as a Secondary Cause of Arterial Hypertension

Abstract Takayasu arteritis (TA) is a rare type of vasculitis that affects mainly the aorta and its major branches. It is highly similar to giant cell arteritis (GCA), and differentiation between them may not be achieved even by histological examination. Arterial hypertension is typical of TA and is caused by stenosis of the renal arteries. Here we report the case of a 59-year-old woman, with a history of dyslipidemia and anemia, seen in the Internal Medicine department for resistant hypertension. Evaluation of secondary causes led to stenosis of the renal arteries. Assessment of target organ involvement was performed by computed tomography angiograph which revealed ectasia of the aortic arch and ascending aorta, tortuous course of the brachiocephalic trunk and the proximal portion of the right common carotid artery; positron-emission tomography which showed diffuse increased uptake in the ascending aorta, compatible with large vessels vasculitis. The patient was submitted to aortic valve replacement with a biological prosthesis combined with myocardial revascularization (Bentall-De Bono procedure). Aortic biopsy specimens showed anatomical and pathological features of GCA and TA. Due to persistently uncontrolled hypertension, prednisone 60 mg was initiated,with significant improvement in patient's condition.