Morphological and etiological analyses of C3 and non-C3 glomerulonephritis in primary membranoproliferative glomerulonephritis using periodic acid-methenamine silver stain electron microscopy: a retrospective multicentered study.

This study elucidated the etiology of C3 glomerulonephritis (C3GN) and non-C3GN with primary membranoproliferative glomerulonephritis (MPGN) using transmission electron microscopy (TEM) and periodic acid-methenamine silver stain (PAM-EM). Thirty-one primary MPGN cases were analyzed by TEM and PAM-EM to distinguish among MPGN I, MPGN II, MPGN III Burkholder subtype (MPGN IIIB), and Anders and Strife subtype (MPGN IIIA/S). Each case was also classified into C3GN or non-C3GN according to the standard C3GN definition using immunostaining. Four cases of MPGN II met C3 glomerulopathy; whereas, four cases of MPGN IIIB did not meet C3 glomerulopathy. Seven of 11 cases (64%) of MPGN I without GBM disruption and 7 of 12 cases (58%) of MPGN IIIA/S with GBM disruption met the non-C3GN criteria with significant immunoglobulins' deposition. Regardless of the C3GN or non-C3GN diagnosis, the deposits in primary MPGN I and MPGN IIIA/S exhibited ill-defined, amorphous, and foggy characteristics similar to those found in postinfectious GN but were different from immune complex (IC) deposits seen in MPGN IIIB. Not only C3GN but also non-C3GN was due to mechanisms other than IC deposition as found in postinfectious GN. Consequently, GBM disruption of MPGN IIIA/S was not due to IC deposition.

Interferon-gamma Release Assay-positive Granulomatous Interstitial Nephritis in a Patient with a History of Diffuse Large B Cell Lymphoma.

Tuberculosis is a common etiology of granulomatous interstitial nephritis (GIN). However, the absence of evidence of lung involvement and lack of mycobacterial isolation in cultures make the etiological diagnosis and treatment decision challenging. We herein report a 46-year-old man with severe renal failure, a persistent fever, and a history of lymphoma. A renal biopsy exhibited GIN. Despite no evidence of tuberculosis except for a positive interferon-gamma release assay (IGRA), the patient was successfully treated with anti-tuberculosis drugs. Our case suggests that anti-tuberculosis therapy should be considered for patients with IGRA-positive GIN after excluding other etiologies.

[Rapidly Developing Pulmonary Cyst Complicated by Pneumothorax Occurred in the Early Post-operative Period after Lung Segmentectomy].

The patient was a 74-year-old man who had undergone surgery for rectal cancer 9 years before and had developed left lung metastasis(S3)3 years and 4 months prior to admission. He had received video assisted left lung wedge resection. He presented with a growing nodular lesion close to the remaining left lung margin and elevated serum carcinoembryonic antigen(CEA)levels, and underwent open extended segmentectomy. The chest drain tube was removed on 3rd post-operative day, but he developed left pneumothorax on 4th post-operative day and a computed tomography(CT)scan revealed a cystic lesion 5.0 cm in size at the base of his left lung. Revision surgery was performed on 8th post-operative day. A pulmonary cyst on the diaphragmatic surface of the lung(S10)was found and location of the air leak was confirmed in the same area. Following wedge resection of the cyst-containing region, the leak ceased completely. Rapid manifestation of a newly formed pulmonary cyst during the acute post-operative period is rare.