Pauci-immune crescentic glomerulonephritis caused to dilemma in a patient with suspected systemic lupus erythematosus: a case report

Systemic lupus erythematosus (SLE) is a chronic autoimmune disease and there is a distinct differentiation of clinical manifestations. Lupus nephritis (LN) is clinically apparent in approximately half of patients. A kidney biopsy is essential to define the kidney injury, exclude other injurious causes, and determine the histopathologic subtypes. Autoantibodies are crucial to the pathogenesis and the deposition of immune complexes in glomeruli is a hallmark of LN. The histopathology of LN is quite varied. Despite pauci-immune LN being an unexpected condition in SLE, it has been observed rarely with the presence of antineutrophil cytoplasmic autoantibodies (ANCA). We present a young male who was admitted to the emergency with syncope. The brain imaging revealed small infarct areas and signs of cerebral vasculitis. Also, he had elevated inflammatory markers, moderate proteinuria, and preserved kidney function. Anti-nuclear antibodies and anti-dsDNA were positive. Pauci-immune crescentic glomerulonephritis (PICGN) was observed in a kidney biopsy, however, ANCA was negative. SLE diagnosis was established by neurological manifestation, specific antibodies, proteinuria, and kidney biopsy findings. We administered a combination induction regimen, including pulse steroid and parenteral cyclophosphamide. The proteinuria was resolved in the follow-up. Our case highlights that SLE-associated ANCA-negative PICGN can be the initial presentation in the absence of typical manifestations. LN exhibits various pathological mechanisms in the kidney. As a consequence, SLE should be considered in the differential diagnosis of all forms of kidney injury.

Diminished PD-L1 regulation along with dysregulated T lymphocyte subsets and chemokine in ANCA-associated vasculitis

ANCA-associated vasculitis (AAV) is a life-threatening disease characterized by small vessel inflammation and pathogenic self-directed antibodies. Programmed death-ligand 1 receptor (PD-1) and programmed cell death ligand-1 (PD-L1) are immune checkpoint molecules crucial for maintaining tolerance and immune homeostasis. After checkpoint inhibition therapy, development of various autoimmune diseases and immune-related adverse events (irAEs) have been observed. Here, we investigated the immunomodulatory roles of neutrophils through the expression of immune checkpoint molecule (PD-L1), migratory molecules (CXCR2), chemotactic chemokines (CXCL5) and other important molecules (BAFF and HMGB1) in development of AAV. We also scrutinized the immune mechanism responsible for development of pauci-immune crescentic GN (PICGN). We demonstrate for the first time that the frequency of PD-L1 expressing neutrophils was significantly reduced in AAV patients compared to healthy controls and correlated negatively with disease severity (BVASv3). Further, in renal biopsy, reduced PD-L1 immune checkpoint expression provides a microenvironment that unleashes uncontrolled activated CD4 + T cells, B cells, neutrophils and macrophages and ultimately causes engulfment of immune complexes leading to PICGN. Furthermore, during remission, reduced neutrophils PD-L1 and CXCR2 expression, increased neutrophils CXCL5 expression and increased peripheral effector memory T cells and increased HMGB1 and BAFF levels in serum, demonstrate the propensity for the persistence of sub-clinical inflammation, which could explain relapse, in this group of diseases.

Divergent manifestations and outcomes of diffuse crescentic immunoglobulin A nephropathy and pauci-immune crescentic glomerulonephritis on long-term

BACKGROUND

Diffuse crescentic IgAN (CIgAN) is an uncommon phenotype of IgAN, which presents as rapidly progressive renal failure, similar to patients with pauci-immune crescentic glomerulonephritis(PCGN). There are limited data on outcomes comparisons between the two.

METHODS

In this single-center, retrospective cohort study, we compared the clinical features, pathological presentation, and renal outcomes of 52 patients with CIgAN and 42 patients with renal-limited PCGN from January 2007 to December 2019.

RESULTS

The CIgAN patients were younger (30.5 ± 13.8 years) than PCGN patients (46.1 ± 11.8 years) (P = 0.001). The CIgAN patients had a higher prevalence of hypertension (86.5% Vs. 41.3%, P = 0.001); and degree of proteinuria (4.2 ± 2.7 g/24 h Vs. 2.3 ± 1.16 g/24 h; P = 0.001) than PCGN patients. The chronicity in terms of global glomerulosclerosis, interstitial fibrosis, and tubular atrophy was higher in the CIgAN group than in the PCGN group. The remission rate with immunosuppression was significantly higher in the PCGN group than in the CIgAN group (P = 0.016). The end-stage renal disease (ESRD) or death within 1 year of diagnosis was significantly more in the CIgAN group (62.3% Vs. 39.1%) than PCGNgroup. For patients who were dialysis-dependent at presentation, the primary outcome of ESRD or death within one year was seen in 90.9% of patients of CIgAN and 44.1% in the PCGN group (P = 0.001). The long-term death non-censored renal survival is poor in the CIgAN group than in PCGN patients. However, patient survival is poor in PCGN patients.

CONCLUSION

CIgAN is a different form of RPGN compared to PCGN and carries a poor prognosis despite similar immunosuppressive therapy in the long term.

Pauci-immune crescentic glomerulonephritis associated with use of trimethoprim-sulfamethoxazole

Drug-induced pauci-immune crescentic glomerulonephritis has been described with several agents, including propylthiouracil, minocycline, D-penicillamine, and hydralazine. We present the case of a 60-year-old man who presented with rapidly progressive glomerulonephritis in the setting of recent use of trimethoprim-sulfamethoxazole complicated by the development of the Stevens-Johnson syndrome, and was found to have biopsy-proven pauci-immune crescentic glomerulonephritis and undetectable anti-neutrophilic cytoplasmic antibodies. We review the existing literature on the potential association between sulfonamides and hypersensitivity polyangiitis.

Antineutrophil Cytoplasmic Antibodies-Negative Pauci-Immune Crescentic Glomerulonephritis Associated with Multiple Myeloma

Pauci-immune crescentic glomerulonephritis (PICGN) is most commonly associated with antineutrophil cytoplasmic antibodies (ANCA). We report a case of chronic, sclerosing ANCA-negative PICGN discovered when a patient presented with multiple myeloma. A 57-year-old woman presented with complaints of nausea, emesis and weakness. She was found to be in renal failure with a serum creatinine of 9.4 mg/dl, mild hyperkalemia and acidosis. She was noted to have normochromic, normocytic anemia with normal platelet and white cell counts, normal plasma proteins and serum protein electrophoresis. Further studies revealed increased concentrations of κ and λ light chains in a ratio of 34.89; a bone marrow biopsy found 12% plasma cells. Serum protein electrophoresis revealed no spike. ANCA, anti-glomerular basement membrane, antineutrophil antibody, hepatitis panel and serum complements were normal. A kidney biopsy result showed chronic sclerosing PICGN plus tubular necrosis, severe tubular atrophy, interstitial fibrosis and severe arteriosclerosis. Congo red stains were negative and electron microscopy showed no intraglomerular deposits. The patient was subsequently treated for myeloma with bortezomib and dexamethasone with good hematologic response but never recovered renal function. She remains on outpatient hemodialysis. Renal manifestations of myeloma often involve glomerular deposition disease, tubulointerstitial disease, with characteristic proteinaceous casts, or both. In contrast, our patient demonstrated neither of these findings but had chronic sclerosing PICGN. Crescentic glomerulonephritis occurring in patients with plasma cell dyscrasias has been previously reported, but the association remains extremely rare.

Primary glomerular diseases in the elderly

Primary glomerular diseases in the elderly population are a frustrating topic due to difficulties in both the diagnosis and decision making about treatment. The most frequent type of primary glomerular disease in elderly is membranous nephropathy; while its counterpart in younger population is IgA nephropathy. The most frequent cause of nephrotic syndrome in the elderly is also membranous nephropathy. Pauci-immune crescentic glomerulonephritis (GN) rate increases both in elderly and very elderly population. Pauci-immune crescentic GNs should be regarded as urgencies in elderly patients as in their younger counterparts due to potential for causing end-stage renal disease in case of delayed diagnosis and treatment, and also causing mortality due to alveolar hemorrhage in patients with pulmonary involvement. Renal biopsy is the inevitable diagnostic method in the elderly as in all other age groups. Renal biopsy prevents unnecessary treatments and provides prognostic data. So advanced age should not be the sole contraindication for renal biopsy. The course of primary glomerular diseases may differ in the elderly population. Acute kidney injury is more frequent in the course and renal functions may be worse at presentation. These patients are more prone to be hypertensive. The decision about adding immune suppressive therapies to conservative methods should be made considering many factors like co-morbidities, drug side effects and potential drug interactions, risk of infection, patient preference, life expectancy and renal functions at the time of diagnosis.

Limited scleroderma with pauci-immune glomerulonephritis in the presence of renal cell carcinoma

Connective tissue disorders increase the risk of malignancy; conversely, they may manifest as rheumatological paraneoplastic syndromes due to an underlying malignancy. We describe the case of a patient with limited scleroderma whose rapid disease progression coincided with the discovery of a renal tumor. A woman, age 75 years, presented with a 3-month history of progressive difficulty grasping objects, unsteadiness, dyspnea, xerostomia, xerophthalmia, and significant weight loss. She had a 10-year history of gastroesophageal reflux and Raynaud's phenomenon. Pertinent physical examination findings included facial telangiectasias, bibasilar inspiratory rales, sclerodactyly, and absent pinprick and vibratory sensation in her toes. She also had swelling and tenderness in several metacarpophalangeal and interphalangeal joints and in both ankles. A renal mass was demonstrated on abdominal computed tomography. A left partial nephrectomy was performed, confirming an unclassified type of renal cell carcinoma, along with a focal proliferative crescentic pauci-immune glomerulonephritis. Medical therapy with rituximab, pulse methylprednisolone, and prednisone led to improvement in her symptoms. The patient's presentation is consistent with a rapid progression of pre-existing limited scleroderma with the development of new rheumatological symptoms, including vasculitis. We propose that this progression was secondary to paraneoplastic stimulation by the renal cell carcinoma. Clinicians should consider looking for a malignancy in patients with connective tissue disorders who present with a myriad of new symptoms.