PMC5790719_01
The renal biopsy findings. (a) Periodic acid-Schiff staining (x400). Endocapillary proliferation was observed with karyorrhexis, fibrinoid necrosis, glomerular basement membrane rupture, cellular crescents, and hyaline thrombus. (b) Periodic acid-methenamine-silver staining (x400). There was no definite spike formation in the capillary walls or mesangial proliferation. (c) Immunohistochemistry revealed faint staining for IgG and C3 deposition in the mesangial and subendothelial regions. (d) Electron microscopy showed very small mesangial and subendothelial deposits, with diffuse and advanced effacement of the foot processes.
1349-7235-56-3311-g001.jpg
PMC5790719_01_1349-7235-56-3311-g001.jpg
g001
Endocapillary glomerulonephritis, with karyorrhexis, fibrinoid necrosis, and rupture of the glomerular basement membrane, cellular crescents, and hyaline thrombus were observed (Fig. 1a). However, there was no definite spike formation in the capillary walls (Fig. 1b). An immunohistochemical examination revealed faint staining for IgG and C3 deposition in the mesangial and subendothelial regions (Fig. 1c). Electron microscopy showed very small mesangial and subendothelial deposits, but there was diffuse and advanced effacement of the foot processes of podocytes (>70%) (Fig. 1d).
Computed tomography and the microscopic appearance of the thymoma. (a) Computed tomography revealed an anterior mediastinal mass (29x15x26 mm) with marked enhancement by contrast medium. (b) Hematoxylin and Eosin staining of resected thymoma (x40).
1349-7235-56-3311-g002.jpg
PMC5790719_01_1349-7235-56-3311-g002.jpg
g002
Computed tomography was performed to investigate systemic complications and an anterior mediastinal mass (29x15x26 mm), that showed marked enhancement by contrast medium (Fig. 2a). Macroscopic inspection of the resected mass revealed a yellowish-white tumor (29x15x26 mm) with a fibrous capsule that featured the proliferation of spindle-like cells in bundles mixed with lymphoid cells (Fig. 2b).
The clinical course of the patient. After thymoma resection, the patient's urinary protein excretion decreased and remission was achieved from proteinuria at two weeks after the initiation of methylprednisolone pulse therapy. The patient's anti-ds-DNA antibody and C3 levels also improved.
1349-7235-56-3311-g003.jpg
PMC5790719_01_1349-7235-56-3311-g003.jpg
g003
Her fever subsided rapidly and her urinary protein excretion also improved to 0.42 g/day after 1 week, while her leukopenia and hypocomplementemia resolved after 2 weeks (Fig. 3), after which she was discharged.