Anti-neutrophil Cytoplasmic Antibody-associated Pauci-immune Crescentic Glomerulonephritis Complicating Sjögren's Syndrome

A case of Sjögren syndrome and anti-neutrophil cytoplasmic antibody-associated vasculitis

Sjögren's syndrome (SS) is a rare disease with the highest reported prevalence of 0.01-0.09%. Anti-neutrophil cytoplasmic antibody-associated vasculitis (AAV) is another rare auto-immune disease (prevalence of 0.0009-0.01%). The co-occurrence of these two separate clinical entities in one patient might rarely be encountered as an overlap syndrome. Here, we present the case of a 60-year-old female patient who had complaints of headache, nausea, weakness, gritty sensation in her eyes, and dry mouth [unstimulated saliva production of 0.033 mL/minute (normal; >0.1 mL/minute)] with a blood pressure of 190/110 mmHg, hypertensive retinopathy, proteinuric kidney disease, positivity of myeloperoxidase anti-neutrophil cytoplasmic antibodies, anti-Ro-52, anti-Ro, and anti-La antibodies. Pauci-immune crescentic proliferative glomerulonephritis was found in a kidney biopsy and successfully treated with cyclophosphamide and methylprednisolone. The co-occurrence of these diseases was first reported in 1992 by Böttinger et al. Since then, nearly 37 cases of SS and AAV have been reported. By reporting this case of primary SS and AAV, we emphasize the importance of auto-antibody tests in searching for the etiology of patients with proteinuria.

Development and validation of a nomogram for renal involvement in primary Sjögren syndrome patients: A retrospective analysis

OBJECTIVE

To establish and validate a nomogram for individualized prediction of renal involvement in pSS patients.

METHODS

A total of 1293 patients with pSS from the First Affiliated Hospital of Wenzhou Medical University between January 2008 and January 2020 were recruited and analyzed retrospectively. The patients were randomly divided into development set (70%, n = 910) and validation set (30%, n = 383). The univariable and multivariate logistic regression were performed to analyze the risk factors of renal involvement in pSS. Based on the regression β coefficients derived from multivariate logistic analysis, an individualized nomogram prediction model was developed and subsequently evaluated by AUC and calibration plot.

RESULTS

Multivariate logistic analysis showed that hypertension, anemia, albumin, uric acid, anti-Ro52, hematuria, and ChisholmMason grade were independent risk factors of renal involvement in pSS. The AUC were 0.797 and 0.750, respectively, in development set and validation set. The calibration plot showed nomogram had a strong concordance performance between the prediction probability and the actual probability.

CONCLUSION

The individualized nomogram for pSS patients those who had renal involvement could be used by clinicians to predict the risk of pSS patients developing into renal involvement and improve early screening and intervention.

Dual Anti-Glomerular Basement Membrane and Anti-Neutrophil Cytoplasmic Antibodies-Positive Rapidly Progressive Glomerulonephritis with Rheumatoid Arthritis and Sjogren's Syndrome: A Case Report and Literature Review

Rapidly progressive glomerulonephritis (RPGN) is a life-threatening disease characterized by rapid progressive deterioration of renal function and extensive formation of crescents. Some antibodies tend to be positive, such as a perinuclear anti-neutrophil cytoplasmic antibody (p-ANCA) and anti-glomerular basement membrane (anti-GBM) antibodies, in most patients with the disease. However, cases of double positivity for the above antibodies are considered to be rare. In addition, both rheumatoid arthritis (RA) and Sjogren's syndrome (SS) are deemed to be independent immune disorders that can cause renal impairment. Nevertheless, the association between RPGN and these two diseases has not been elucidated in previous studies. Here, we provide a case of RPGN with the concurrence of RA and SS characterized by double positivity in anti-GBM antibodies and p-ANCA. After aggressive treatment with cyclophosphamide, glucocorticoids, and plasma exchange, the patient improved significantly. Despite the malignant event of arteriovenous fistula rupture and bleeding during treatment, the patient survived with renal function recovery for the rest of the follow-up period.

Reduced Mortality Associated With the Use of Metformin Among Patients With Autoimmune Diseases

OBJECTIVE

Metformin has been linked to anti-proliferative and anti-inflammatory mechanisms. In this study, we aimed to examine the long-term impact of metformin on mortality and organ damage in patients with autoimmune diseases and type 2 diabetes mellitus (T2DM).

METHODS

We conducted a cohort study using the National Health Insurance Research Database in Taiwan between 1997 and 2013. Based on metformin and other anti-diabetic agent prescriptions, we categorized all patients with autoimmune diseases into either the metformin group (metformin administration for at least 28 days) or the non-metformin group. The primary outcomes were all-cause mortality and annual admission rate, while the secondary outcome was target organ damage. We followed patients from the index date to the date on which the event of interest occurred, death, or the end of this study.

RESULTS

Our cohort study included 3,359 subjects for analysis. During a mean follow up of 5.2 ± 3.8 years, the event rate of all-cause mortality was 228 (33.6%) in the metformin group and 125 (36.9%) in the non-metformin group. The risk of both all-cause mortality and annual number of admissions for autoimmune diseases was significantly lower in the metformin group than in the non-metformin group [hazard ratio (HR) 0.77; 95% CI 0.62-0.96 and risk ratio (RR) 0.81; 95% CI 0.73-0.90, respectively].

CONCLUSION

Metformin may add benefits beyond T2DM control with regard to reducing all-cause mortality and admission rate, as well as minimizing end-organ injury in lungs and kidneys among patients with autoimmune diseases.

[Renal involvement in Sjögren's syndrome]

Primary Sjögren syndrome is an autoimmune disorder characterized by lymphoplasmacytic infiltration of the exocrine (salivary and lachrymal) glands resulting in sicca symptoms (dryness). Systemic complications can occur in primary Sjögren syndrome, but renal involvement is rare, affecting<10% patients. The most frequent form of nephropathy in primary Sjögren syndrome is tubulointerstitial nephritis, where infiltration of the kidney by plasma cells is a key feature and shows similarity to the lymphoplasmacytic infiltration of the salivary glands. Electrolyte disturbances may occur in primary Sjögren syndrome, such as renal distal tubular acidosis, diabetes insipidus, Gitelman syndrome, or Fanconi syndrome. Glomerular involvement is less frequently detected in patients with primary Sjögren syndrome, but can take the form of membranoproliferative glomerulonephritis secondary to cryoglobulinaemia. The renal prognosis in patients with primary Sjögren syndrome and TIN or glomerular disease is usually good, but the risk of chronic kidney disease remains significant for some patients. Appropriate screening must be performed at least once a year in patients with systemic primary Sjögren syndrome in order to facilitate the early detection of renal complications. In this Review, we discuss the epidemiology, pathophysiology, differential diagnosis, and treatment of renal disease in primary Sjögren syndrome.

Emergence of Smoldering ANCA-associated Glomerulonephritis during the Clinical Course of Mixed Connective Tissue Disease and Sjögren's Syndrome

A 67-year-old woman presented with hematuria and proteinuria 16 and 11 months ago, respectively. She had been followed up as mixed connective tissue disease and Sjögren's syndrome for over 19 years. Blood chemistry showed no elevated serum creatinine or C-reactive protein but did reveal myeloperoxidase-antineutrophil cytoplasmic antibody (MPO-ANCA) of 300 U/dL. A kidney biopsy showed pauci-immune focal necrotizing glomerulonephritis. She was treated with prednisolone and rituximab, resulting in normal urinalysis and decreased MPO-ANCA. The complication of ANCA-associated glomerulonephritis should not be overlooked when abnormal urinalysis findings appear in the course of connective tissue disease, irrespective of the presence of rapidly progressive glomerulonephritis.

Dual anti-neutrophil cytoplasmic antibody-related pauci-immune crescentic glomerulonephritis in a patient with Sjögren's syndrome

Sjögren's syndrome is an autoimmune disease that primarily affects exocrine glands. Renal involvement of Sjögren's syndrome may lead to tubulointerstitial disease, whereas secondary glomerulopathies such as anti-neutrophil cytoplasmic antibody (ANCA)-related pauci-immune crescentic glomerulonephritis are rarely observed. In addition, crescent glomerulonephritis that is simultaneously positive for both myeloperoxidase (MPO)-ANCA and proteinase 3 (PR3)-ANCA has never been reported in Sjögren's syndrome. Here, we report a case of pauci-immune crescentic glomerulonephritis exhibiting positivity for both MPO- and PR3-ANCAs in a patient with primary Sjögren's syndrome. A 71-year-old female was hospitalized for cough, blood-tinged sputum, and dyspnea two weeks after diagnosis with Sjögren's syndrome. On admission, serum anti-nuclear antibody, anti-Ro/SS-A antibody, MPO-ANCA, and PR3-ANCA were all positive, and serum blood urea nitrogen and creatinine (Cr) levels were 42.7 and 2.9 mg/dL, respectively. On the seventh day of hospitalization, the patient's serum Cr level was 5.7 mg/dL, indicating rapidly progressive glomerulonephritis. Renal biopsy resulted in the diagnosis of ANCA-related pauci-immune crescentic glomerulonephritis, for which intravenous methylprednisolone (7 mg/kg/day) was administered for three consecutive days, followed by combination therapy with oral prednisolone (1 mg/kg/day) and intravenous cyclophosphamide (500 mg/m(2)). The patient was positive in the Schirmer's I test, and a salivary gland biopsy showed sialadenitis with lympho-plasmacytic infiltrations. On day 28 of hospitalization, the patient was discharged after amelioration of respiratory symptoms and azotemia. At 6 months after discharge, the patient continued to receive appropriate daily medications and was negative for both MPO- and PR3-ANCAs, with a slight elevation in serum Cr levels.

Renal involvement in primary Sjögren syndrome

Primary Sjögren syndrome (pSS) is an autoimmune disorder characterized by lymphoplasmacytic infiltration of the exocrine (salivary and lachrymal) glands that results in sicca symptoms (dryness of the eyes and mouth). Systemic complications can occur in pSS, but renal involvement is rare, affecting <10% patients. The most frequent form of nephropathy in pSS is tubulointerstitial nephritis (TIN), in which infiltration of the kidney by plasma cells is a key feature and shows similarity to the lymphoplasmacytic infiltration of the salivary glands. Electrolyte disturbances may occur in pSS, such as renal distal tubular acidosis, diabetes insipidus, Gitelman syndrome or Fanconi syndrome. Glomerular involvement is less frequently detected in patients with pSS, but usually takes the form of membranoproliferative glomerulonephritis secondary to cryoglobulinaemia. The renal prognosis in patients with pSS and TIN or glomerular disease is usually favourable, but the risk of chronic kidney disease remains high in patients with TIN. Appropriate screening must be performed at least once a year in patients with systemic pSS in order to facilitate the early detection of renal complications. In this Review we discuss the epidemiology, pathophysiology, differential diagnosis and treatment of renal disease in pSS.

ANCA-associated vasculitis in patients with primary Sjögren's syndrome: detailed analysis of 7 new cases and systematic literature review

OBJECTIVES

To describe the clinical presentation, management and prognosis of patients diagnosed with both primary Sjögren's syndrome (pSS) and anti-neutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV).

METHODS

French nation-wide survey completed by a systematic literature review.

RESULTS

This work identified 7 new cases of coexisting pSS and AAV: 2 microscopic polyangiitis (MPA), 2 granulomatosis with polyangiitis (GPA), 2 anti-myeloperoxidase (MPO)-ANCA renal-limited AAV, and 1 eosinophilic granulomatosis with polyangiitis (EGPA). The systematic literature search identified 15 previously published cases. Among the 22 patients, 19 were females. Mean age at diagnosis of AAV was 63.9±9.8years. All individuals with available information experienced at least one extra-glandular manifestation attributable to pSS. p-ANCA with anti-MPO specificity were found in 76.2% (16/21), c-ANCA with anti-PR3 specificity in 14.3% (3/21) and isolated c-ANCA in 13.6% (3/22). Vasculitis involved kidneys (n=13), lungs (n=8), skin (n=6), peripheral nerves (n=5), central nervous system (n=2), small bowel (n=1), muscle (n=1), ear chondritis (n=1) and sinuses (n=1). The mean AAV follow-up was 73.5 (±120.0) months. While on treatment, disease remission occurred in 77.3% of cases, and one death was reported in the first 6months after diagnosis.

CONCLUSION

This work shows that AAV may occur in patients with pSS. These are most commonly p-ANCA associated vasculitis with anti-MPO specificity. AAV may reveal an underlying pSS or arise during its evolution, but did not precede pSS in any of these cases. AAV occurrence appears to be correlated with extra-glandular manifestations of pSS.

Huai Qi Huang ameliorates proteinuria and hematuria in mild IgA nephropathy patients: a prospective randomized controlled study

BACKGROUND/PURPOSE

Huai Qi Huang (HQH) is a compound Chinese herbal medicine that contains Trametes robiniophila murr, wolfberry fruit, and Polygonatum. In the present study, we investigated the effects of HQH on patients with mild immunoglobulin A nephropathy (IgAN) through a prospective randomized controlled study.

METHODS

Forty-five adults diagnosed with IgAN according to renal pathology, who had hematuria or/and proteinuria (≤ 2 g/day), were randomly assigned to receive HQH or no treatment for 12 weeks. Twenty-four hour urinary protein excretion and hematuria were measured at Weeks 0, 4, 8, and 12. The rate of complete remission of proteinuria and hematuria was evaluated. Any adverse events induced by HQH were also observed during the treatment period.

RESULTS

Twenty-four hour urinary protein excretion was significantly reduced by HQH treatment compared with that in the control group at Weeks 8 and 12. A much higher rate of complete remission of proteinuria was observed in the HQH group than in control group at Week 12. HQH administration also obviously reduced the extent of hematuria compared with that in the control group at Week 12. HQH treatment dramatically increased the rate of complete remission of hematuria compared with that in control group at Weeks 8 and 12. No obvious adverse events caused by HQH were observed.

CONCLUSION

HQH could be a new conservative therapy for IgAN patients who cannot tolerate steroids and immunosuppressive agents. The relapse rate after discontinuing treatment still needs further investigation.