Paraneoplastic Seronegative Pauci-Immune Glomerulonephritis Associated with Lung Adenocarcinoma Responds to Rituximab: A Case Report

A case of ANCA-negative pauci-immune crescentic glomerulonephritis with lung adenocarcinoma with mediastinal involvement successfully treated by corticosteroid and radiation therapy

Pauci-immune crescentic glomerulonephritis (PICGN) is one of the pathologies causing rapidly progressive glomerulonephritis, often associated with anti-neutrophil cytoplasmic antibody (ANCA); however, in 10-30% of cases, ANCAs are negative. While a relatively large number of cases of ANCA-positive PICGN complicated with malignancy have been previously reported, the number of cases of ANCA-negative PICGN with malignancy is limited. The prognosis for such cases was poor, and many patients died within a relatively short period. Here, we report the case of ANCA-negative PICGN complicated with malignancy successfully treated by corticosteroid and radiation therapy. A 63-year-old Japanese man was admitted to our hospital due to spiking fevers in the previous 3 months. Based on the findings of imaging and pathological tests, he was diagnosed with locally advanced lung adenocarcinoma with mediastinal involvement. After admission, his renal function rapidly deteriorated, and urinalysis showed heavy proteinuria. In serological tests, serology for autoantibodies, including ANCAs, was negative. The kidney biopsy revealed PICGN with prominent endocapillary proliferation. We administered corticosteroid therapy for glomerulonephritis and subsequent radiation therapy for lung carcinoma, both of which were effective. He has been alive without progression of malignancy or kidney disease for 5 years after discharge. In patients with malignancy presenting with acute deterioration of kidney function, although infrequent, one of the conceivable pathological conditions to consider is ANCA-negative PICGN associated with malignancy. In such cases, even with negative antibodies such as ANCA, pathological examination is warranted, and a combination of anti-tumor therapy and immunosuppressive therapy is expected to be effective.

Case Report of MPO+ ANCA Vasculitis with Pauci-immune GN Associated with Invasive Ductal Carcinoma of the Breast

BACKGROUND

Malignancy-associated vasculitis usually presents in the form of polyarteritis nodosa or leukocytoclastic vasculitis. However, ANCA vasculitis associated with malignancy is rare. Here, we present a case of MPO+ ANCA vasculitis with pauci-immune GN associated with invasive ductal carcinoma of the breast.

CASE PRESENTATION

A 66-year-old female with a history of rheumatoid arthritis, Hashimoto's thyroiditis, and psoriasis presented with multiple joint pain, body aches, petechial rash, paresthesia and numbness, and deranged renal function a month after diagnosis of localized left breast invasive ductal carcinoma. Renal biopsy showed crescentic pauci-immune glomerulonephritis, and serology was positive for Perinuclear Antineutrophil Cytoplasmic Antibody (P-ANCA) and myeloperoxidase (MPO). The disease course was complicated by diverticulitis with peritonitis and intraperitoneal abscess collection, which required laparoscopic peritoneal lavage and additional interventional radiology-guided drainage of the abscess. We treated the patient successfully with steroids, rituximab, and mastectomy for left breast malignant lesions, resulting in the resolution of symptoms, normalization of inflammatory markers, and ANCA seroconversion.

CONCLUSION

Treating ANCA-associated Vasculitis (AAV) in surgical emergencies like bowel perforation can be challenging. Individualized treatment strategy tailored to patients' acute needs is crucial. In this case, we considered malignancy-associated vasculitis and pursued treatment that fit the patient's clinical situation in a multidisciplinary approach.

Case Report: Hematologic Recovery Following Stereotactic Ablative Radiotherapy in a Patient With Early-Stage Non-Small Cell Lung Cancer and Paraneoplastic Myelofibrosis

Herein, we report the first case presentation of paraneoplastic myelofibrosis associated with cancer. Paraneoplastic syndromes occur in some patients with thoracic malignancies; however, myelofibrosis is not commonly seen in non-small cell lung cancer (NSCLC). We report a case of myelofibrosis in a patient with a new diagnosis of NSCLC that resolved after stereotactic ablative radiotherapy (SABR). In conclusion, NSCLC may evoke unexpected systemic effects that resolve with treatment.

Paraneoplastic Glomerular Diseases

Paraneoplastic glomerular diseases (GNs) are rare manifestations in patients with underlying hematologic and solid organ malignancies and can occur before or after the detection of cancer. In the absence of established algorithms for investigation and reliable tests, they remain difficult to diagnose. Given the heterogeneity and infrequency of cases, the pathogenesis of most paraneoplastic GNs is poorly understood. Most of our recent understanding of paraneoplastic GNs has emerged from the discovery of target antigens in membranous nephropathy such as thrombospondin type-1 domain-containing protein 7A and neural epidermal growth factor-like 1 protein that appear to be promising in differentiating a primary vs paraneoplastic cause of membranous nephropathy. Treatment of paraneoplastic GNs is usually directed at the underlying malignancy. This review will focus on the epidemiology, pathogenesis, and diagnosis of paraneoplastic glomerular processes.

ANCA-Negative Pauci-Immune Necrotizing Glomerulonephritis: A Case Series and a New Clinical Classification

RATIONALE & OBJECTIVE

Pauci-immune necrotizing glomerulonephritis (PING) is usually associated with the presence of antineutrophil cytoplasmic antibodies (ANCA). However, a minority (2%-3%) of patients with PING do not have detectable ANCA. We assessed the clinical spectrum and outcome of patients with ANCA-negative PING.

STUDY DESIGN

Case series.

SETTING & PARTICIPANTS

74 patients with ANCA-negative PING diagnosed in 19 French nephrology centers between August 2006 and December 2018 were included in the series. Patients' medical files were reviewed, and kidney biopsies were centrally reexamined by pathologists who were masked to the diagnosis.

FINDINGS

Median age at diagnosis was 69 (IQR, 61-76) years. The clinical and pathological features were remarkable for a high frequency of extrarenal manifestations (54%), nephrotic syndrome (32%), and endocapillary hypercellularity (31%). Three main subtypes of ANCA-negative PING were observed: infection-associated (n=9[12%]), malignancy-associated (n=6[8%]), and primary (n=57[77%]). For patients with primary PING, induction treatment included mainly corticosteroids (n=56[98%]), cyclophosphamide (n=37[65%]), and rituximab (n=5[9%]). Maintenance treatment consisted mainly of corticosteroids (n=42[74%]), azathioprine (n=18[32%]), and mycophenolate mofetil (n=11[19%]). After a median follow-up period of 28 months, 28 (38%) patients had died and 20 (27%) developed kidney failure (estimated glomerular filtration rate<15mL/min/1.73m²). Eleven (21%) patients (9 with primary and 2 with malignancy-associated PING) relapsed.

LIMITATIONS

Retrospective study and limited number of patients; electron microscopy was not performed to confirm the absence of glomerular immune deposits.

CONCLUSIONS

Within the spectrum of ANCA-negative PING, infection and malignancy-associated forms represent a distinct clinical subset. This new clinical classification may inform the management of ANCA-negative PING, which remains a severe form of vasculitis with high morbidity and mortality rates despite immunosuppressive treatments.