Membranous nephropathy in a patient with pulmonary tuberculosis infection and lung adenocarcinoma: a case report

Abstract

We report a case of membranous nephropathy (MN) in a patient with tuberculosis infection and lung adenocarcinoma. A 50-year-old Filipino woman underwent a renal biopsy for the evaluation of proteinuria and hematuria. Immunofluorescence analysis revealed positive staining of IgG in the glomerular basement membrane and mesangial matrices, while electron microscopy demonstrated the presence of sub-epithelial deposits, suggesting MN. To screen for secondary causes of MN, we conducted a computed tomography (CT) scan of the chest and abdomen, which revealed a ground-glass opacity in the middle lobe of the right lung and an enlarged paraaortic lymph node. A T-SPOT test was positive, suggesting the possibility of a latent tuberculosis infection, as she was asymptomatic. A follow-up chest CT scan showed persistent presence of the ground-glass opacities, suggesting a non-infectious cause. Video-assisted thoracoscopic resection of the middle right lobe and partial resection of the lower right lobe were performed because the possibility of lung cancer could not be excluded. Notably, pathological analysis of the lung revealed adenocarcinoma in the middle lobe and epithelioid granuloma in the lower lobe, suggesting an active tuberculosis infection. One month after surgery, anti-tuberculosis treatment was initiated. Thereafter, her proteinuria, which had increased to 6 g/gCre preoperatively, began to decrease. Five months after surgery, the patient achieved complete remission. The speed of remission suggests that tuberculosis likely played a primary role in the etiology of MN. Our case underscores the importance of screening tests for infections and malignancies in patients with MN, even if suggestive symptoms are absent.

Analysis of Clinicopathological Characteristics of Malignancy Patients with Membranous Nephropathy and Literature Review

“…Previous investigations have demonstrated that remission of MN can be observed following effective antitumor treatment in patients with MN with concomitant malignancy. 8,10,15,16,18,19,21 Our study supports these findings. Specifically, in case 4, case 8, case 10, and case 14, patients who did not receive immunosuppressive therapy, achieved PR/CR of MN after surgical removal of the tumor or chemotherapy.…”

“…We retrieved and summarized the literature on MN patients with concomitant malignancy from 1990 to the present, screening 17 articles encompassing a total of 21 patients in whom MN-specific antigen staining was performed on both renal and tumor tissues simultaneously (Figure 3). [7][8][9][10][11][12][13][14][15][16][17][18][19][20][21][22][23] Among these patients, 71.4% (15/21) were male, with a median age of 61.0 years (56. 3, 72.8).…”

Two-sample mendelian randomization reveals a causal association between membranous nephropathy and lung cancer

“…Clinically, cancer-related nephropathy is on the rise, but the pathological types are atypical and the etiology is unclear 3,4 . Although several reports mention improvement in symptoms of nephrotic syndrome in patients with MN after aggressive tumor treatment [5][6][7] , the evidence that directly reveals this relationship is still limited, controversial, and speculative 8 . It has been reported that the processes of MN and malignancy often develop in parallel, with tumor antigens or tumor-reactive antibodies found within glomerular immune deposits, supporting an association between the two diseases 9 .…”

The Antigenic Landscape of Pediatric Membranous Nephropathy

“…Twenty-three patients had positive antinuclear autoantibodies. Infectious agents, a known trigger of MN, 5 , 6 , 7 , 8 , 9 were not identified (including hepatitis B virus, hepatitis C virus, HIV, malaria, leprosy, or tuberculosis).…”