Hypertrophic pachymeningitis associated with antineutrophil cytoplasmic antibody-associated vasculitis: a case series of 15 patients.

OBJECTIVE: We aimed to describe the clinical characteristics and treatment course of hypertrophic pachymeningitis (HPM) in patients with antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV). METHODS: We retrospectively analysed 15 patients (11 men and four women). HPM was diagnosed based on thickening and enhancing of the brain and/or spinal dura mater on gadolinium-enhanced magnetic resonance imaging (MRI) T1 sequence. RESULTS: The median age at HPM onset was 60 years. Headache and cranial nerve impairment were observed in 14 and 10 patients, respectively. Otitis media and/or mastoiditis were found as complications of AAV in 11 patients. Fourteen patients were classified as having granulomatosis with polyangiitis (GPA). Single-positive myeloperoxidase-ANCA, single-positive proteinase 3-ANCA, and double-positive ANCA were identified in seven patients, five patients, and one patient, respectively. With MRI, thickening of the dura mater in the cranial fossa and tentorium cerebelli was found in 10 and eight patients, respectively. For remission induction, all patients were treated with corticosteroids, and immunosuppressants were added in 10 patients. Dura mater thickening partially improved in all patients, and cranial neuropathy completely remitted in eight patients. In a median follow-up of 43 months, four patients had HPM relapse and underwent reinduction therapy. All six patients treated with cyclophosphamide at initial therapy did not relapse. CONCLUSIONS: HPM was mostly associated with patients with GPA with otitis media and/or mastoiditis having either type of ANCA serology. Treatment with corticosteroids with or without immunosuppressants was effective. However, HPM relapse occasionally occurred, especially when cyclophosphamide was not used in initial treatment.

The correlation of urinary podocytes and podocalyxin with histological features of lupus nephritis.

Objectives The objective of this study was to test the correlation of urinary podocyte number (U-Pod) and urinary podocalyxin levels (U-PCX) with histology of lupus nephritis. Methods This was an observational, cross-sectional study. Sixty-four patients were enrolled: 40 with lupus nephritis and 24 without lupus nephritis (12 lupus nephritis patients in complete remission and 12 systemic lupus erythematosus patients without lupus nephritis). Urine samples were collected before initiating treatment. U-Pod was determined by counting podocalyxin-positive cells, and U-PCX was measured by sandwich ELISA, normalized to urinary creatinine levels (U-Pod/Cr, U-PCX/Cr). Results Lupus nephritis patients showed significantly higher U-Pod/Cr and U-PCX/Cr compared with patients without lupus nephritis. U-Pod/Cr was high in proliferative lupus nephritis (class III±V/IV±V), especially in pure class IV (4.57 (2.02-16.75)), but low in pure class V (0.30 (0.00-0.71)). U-Pod/Cr showed a positive correlation with activity index ( r=0.50, P=0.0012) and was independently associated with cellular crescent formation. In contrast, U-PCX/Cr was high in both proliferative and membranous lupus nephritis. Receiver operating characteristic analysis revealed significant correlation of U-Pod/Cr with pure class IV, class IV±V and cellular crescent formation, and the combined values of U-Pod/Cr and U-PCX/Cr were shown to be associated with pure class V. Conclusions U-Pod/Cr and U-PCX/Cr correlate with histological features of lupus nephritis.

Analysis of cytochrome P450 gene polymorphism in a lupus nephritis patient in whom tacrolimus blood concentration was markedly elevated after administration of azole antifungal agents.

WHAT IS KNOWN AND OBJECTIVE: Both itraconazole (ITCZ) and voriconazole (VCZ) are potent inhibitors of cytochrome P450 (CYP) 3A, and their effects have been reported to be equal. However, ITCZ is metabolized by CYP3A, whereas VCZ is mainly metabolized by CYP2C9 and CYP2C19 and only partially by CYP3A. We experienced the case of a patient who showed a 5-fold increase in trough levels of tacrolimus (FK) level after switching from ITCZ to VCZ. Our objective is to discuss the mechanism of the increase drug-drug interaction in terms of serum concentration of the azole drugs and patient pharmacogenomics. CASE SUMMARY: A 53-year-old woman was treated with FK (1 mg/day) for lupus nephritis. Because fungal infection was suspected, she received ITCZ (100 mg/day). When ITCZ was replaced with VCZ (400 mg/day), the blood concentration of FK increased markedly from 6·1 to 34·2 ng/mL. During coadministration with FK, the levels of ITCZ and VCZ were 135·5 ng/mL and 5·5 µg/mL, respectively, with the VCZ level around 3-fold higher than the previously reported level (1·4-1·8 µg/mL). Her CYP genotypes were CYP2C19*1/*2, CYP3A4*1/*1 and CYP3A5*3/*3. WHAT IS NEW AND CONCLUSION: The patient was a CYP2C19 intermediate metabolizer (IM) and deficient in CYP3A5. The increase in plasma VCZ level appears to have been at least in part, associated with the CYP2C19 IM phenotype. One possible explanation for the marked increase in blood FK concentration was increased inhibition of CYP3A because of the impaired metabolism and subsequent increased plasma concentration of VCZ. This case shows that the severity of drug interactions may be influenced by metabolic gene polymorphism.

Expression of IL-19 and its receptors in RA: potential role for synovial hyperplasia formation.

OBJECTIVE: IL-19 is a novel cytokine of the IL-10 family. In this study, we sought to examine whether IL-19 plays a role in the pathogenesis of RA. METHODS: Expression of IL-19, IL-20 receptor 1 (IL-20R1) and IL-20R2 was examined by RT-PCR and immunohistochemical analysis in rheumatoid synovium. The effects of IL-19 on synovial cells established from rheumatoid synovium (RASCs), with regard to IL-6 production and signal transducers and activators of transcription3 (STAT3) activation, were examined by ELISA and western blot analysis, respectively. The effect of IL-19 on RASC apoptosis was examined by Hoechst staining, flow cytometry analysis of annexin V binding and caspase-3 activity. RESULTS: IL-19, IL-20R1 and IL-20R2 mRNA were detected by RT-PCR in synovial tissues from RA patients. Immunohistochemical analysis showed IL-19 was predominantly expressed in the hyperplastic lining layers of RA synovial tissues. The majority of IL-19-positive cells were vimentin-positive and CD68-positive synovial cells, serving as markers of fibroblasts and macrophages, respectively. IL-20R1 and IL-20R2 (IL-20Rs) were expressed in both the lining and sublining layers of RA synovium. In RASC, IL-19 was induced by lipopolysaccharide stimulation and constitutive expression of IL-20Rs was observed, suggesting IL-19 has an autocrine action. In terms of this function, IL-19 induced STAT3 activation and increased IL-6 production by RASC above the medium control. Moreover, IL-19 significantly reduced RASC apoptosis induced by serum starvation. CONCLUSIONS: These data suggest that IL-19, produced by synovial cells, promotes joint inflammation in RA by inducing IL-6 production and decreasing synovial cell apoptosis.

Revised classification of lupus nephritis is valuable in predicting renal outcome with an indication of the proportion of glomeruli affected by chronic lesions.

OBJECTIVES: To determine if the International Society of Nephrology/Renal Pathology Society (ISN/RPS) 2003 classification of lupus nephritis (LN) is helpful in predicting renal outcome. METHODS: A total of 92 patients with LN who underwent renal biopsy in our hospital were re-classified according to the ISN/RPS 2003 criteria. RESULTS: The mean patient age was 36.8 yrs and the median observation period was 65 months. The relative frequency for each class was as follows: Class I (minimal mesangial LN) 0%, Class II (mesangial proliferative LN) 13%, Class III (focal LN) 17%, Class IV (diffuse LN) 60% and Class V (membranous LN) 10%. Within Class IV, diffuse segmental (Class IV-S) was 25% and diffuse global (Class IV-G) 75%. During the observation period, renal function was more likely to deteriorate in Class IV-G cases than in Class IV-S cases. Importantly, when Class IV-G was subdivided into cases involving active lesion alone [IV-G (A)] or chronic lesion [IV-G (A/C)], the majority of cases in IV-G (A) was nephrotic, but responded well to therapy. In contrast, renal function declined only in IV-G (A/C) cases. Patients with Class IV-G (A/C) had persistent proteinuria in spite of intensified therapies. Moreover, the higher proportion of chronic lesions was related with the deterioration of renal function. CONCLUSIONS: This study showed that in Class IV-G cases, renal outcome differed in the presence of chronicity. Chronicity could be a critical factor in predicting outcome. Thus, the revised classification of LN is clinically valuable in identifying different renal outcomes among patients with diffuse LN.

Modulation of apoptosis by the cyclin-dependent kinase inhibitor p27(Kip1).

Proliferation and apoptosis are increased in many types of inflammatory diseases. A role for the cyclin kinase inhibitor p27(Kip1) (p27) in limiting proliferation has been shown. In this study, we show that p27(-/-) mesangial cells and fibroblasts have strikingly elevated rates of apoptosis, not proliferation, when deprived of growth factors. Apoptosis was rescued by restoration of p27 expression. Cyclin A-cyclin-dependent kinase 2 (CDK2) activity, but not cyclin E-CDK2 activity, was increased in serum-starved p27(-/-) cells, and decreasing CDK2 activity, either pharmacologically (Roscovitine) or by a dominant-negative mutant, inhibited apoptosis. Our results show that a new biological function for the CDK inhibitor p27 is protection of cells from apoptosis by constraining CDK2 activity. These results suggest that CDK inhibitors are necessary for coordinating the cell cycle and cell-death programs so that cell viability is maintained during exit from the cell cycle.

The subcellular localization of cyclin dependent kinase 2 determines the fate of mesangial cells: role in apoptosis and proliferation.

Apoptosis is closely linked to proliferation. In this study we showed that inducing apoptosis in mouse mesangial cells with ultraviolet (UV) irradiation was associated with increased cyclin A-cyclin dependent kinase (CDK) 2 activity. Inhibiting CDK2 activity with Roscovitine or dominant negative mutant reduced apoptosis. Because apoptosis typically begins in the cytoplasm, we tested the hypothesis that the subcellular localization of CDK2 determines the proliferative or apoptotic fate of the cell. Our results showed that cyclin A-CDK2 was nuclear in proliferating cells. However, inducing apoptosis in proliferating cells with UV irradiation was associated with a decrease in nuclear cyclin A and CDK2 protein levels. This coincided with an increase in protein and kinase activity for cyclin A-CDK2 in the cytoplasm. Translocation of cyclin A-CDK2 also occurred in p53-/- mesangial cells. Finally, we showed that caspase-3 activity was significantly reduced by inhibiting CDK2 activity with Roscovitine. In summary, our results show that apoptosis is associated with an increase in cytoplasmic cyclin A-CDK2 activity, which is p53 independent and upstream of caspase-3. We propose that the subcellular localization of CDK2 determines the proliferative or apoptotic fate of the cell.

Tubulointerstitial mast cell infiltration in glomerulonephritis.

Mast cells are involved in chronic inflammation and tissue fibrosis. To determine whether these cells are also involved in tubulointerstitial injury in glomerulonephritis, we assayed mast cell infiltration in the kidneys of 107 patients with primary or secondary glomerulonephritis. Using a monoclonal antihuman tryptase antibody, we detected mast cells in the renal cortical tubulointerstitium, the periglomerular areas, and the medullary interstitium, but not in glomeruli. Renal cortical tubulointerstitial mast cells, including periglomerular area, were estimated as 0.8+/-1.6 cells/mm2 in minimal change nephrotic syndrome (n=7), 1.5+/-0.7 cells/mm2 in minor glomerular abnormalities without nephrotic syndrome (n=7), 6.5+/-7.7 cells/mm2 in membranous nephropathy(n=10), 12.9+/-15.5 cells/mm2 in lupus nephritis (n=15), 13.4+/-8.3 cells/mm2 in focal segmental glomerular sclerosis (n=6), 18.5+/-21.1 cells/mm2 in ANCA-related nephropathy (n=5), 19.8+/-14.2 cells/mm2 in membranoproliferative glomerulonephritis (n=5), 21.3+/-17.7 cells/mm2 in immunoglobulin A (IgA) nephropathy (n=42), and 33.0+/-33.8 cells/mm2 in diabetic nephropathy (n=10). Except for patients with the rapidly progressive glomerulonephritic syndrome (RPGN), the number of infiltrating mast cells significantly correlated with the serum concentration of creatinine at the time of renal biopsy (r=0.59; P < 0.0001) and with the intensity of tubulointerstitial injury as measured by leukocyte infiltration (r=0.72; P < 0.0001) and fibrosis (r=0.75; P < 0.0001). In contrast, mast cell infiltration did not correlate with urinary protein excretion. In relation to serum creatinine concentration, the number of mast cells was fewer in patients with RPGN than in those with chronic glomerulonephritis. These data suggest that mast cells may contribute to the renal deterioration in glomerulonephritis by inducing chronic tubulointerstitial injury.

A case of cimetidine-induced acute tubulointerstitial nephritis associated with antineutrophil cytoplasmic antibody.

We present a case of acute tubulointerstitial nephritis (ATIN) that developed in a 63-year-old man who had been taking cimetidine for treatment of a gastric ulcer. The constellation of clinical, laboratory, and histopathologic findings suggested drug-induced ATIN. Of interest, the patient had antineutrophil cytoplasmic antibody (ANCA) in his sera, reactive with myeloperoxidase, elastase, and lactoferrin. Prominent renal histological features included marked plasmacyte infiltration into the renal interstitium. Withdrawal of cimetidine resulted in complete resolution of renal findings, and the titers of ANCA concomitantly declined. Thus, cimetidine may have played a causative role in the development of ANCA-associated ATIN.

Combined treatment with cyclophosphamide and prednisolone can induce remission of nephrotic syndrome in a patient with renal amyloidosis, associated with rheumatoid arthritis.

A 67-year-old woman, who had been diagnosed with classical rheumatoid arthritis (RA), was admitted to our hospital because of massive proteinuria. Biopsy of the kidney revealed deposition of amyloid fibrils in the subepithelial and subendothelial spaces of the glomerular capillary walls. Though the treatment with prednisolone and dipyridamole against nephrotic syndrome and amyloidosis due to RA was not effective, cyclophosphamide, which was added after tapering of prednisolone, was able to induce remission of nephrotic syndrome after two years. The levels of CRP and serum amyloid A protein (SAA) returned to within the normal limits. As the impairment of renal function is thought to be due to deposition of amyloid supplied from the precursors of amyloid fibrils filtered from the general circulation in RA patients, remission of nephrotic syndrome might result from the suppression of production of SAA or removal of amyloid fibrils. Cyclophosphamide, which has the potential both to suppress disease activity in RA and to produce degradation of amyloid fibrils in glomeruli, may be useful against renal or systemic amyloidosis complicated by RA.

Widespread crystalline inclusions affecting podocytes, tubular cells and interstitial histiocytes in the myeloma kidney.

Numerous crystalline inclusions were observed in glomerular and tubular epithelial cells in a 46-year-old female patient with multiple myeloma and renal dysfunction. On light microscopy, epithelial cells were filled with homogenous materials and were remarkably swollen. Infiltrations of histiocytes with expanded cytoplasm were also seen in the interstitium of the kidney and bone marrow. On electron microscopy, cytoplasmic inclusions had crystalline structure showing rhomboid and oval shapes. Immunofluorescence study revealed that these cells were positive for IgG-kappa. The combination chemotherapy followed by autologous stem cell transplantation led to a partial resolution of her renal dysfunction, continued by a slight reduction in the number of crystalline-containing podocytes at the second renal biopsy. Crystal inclusions in the kidney are rarely found and cause renal impairment in multiple myeloma.

Effects of posture on creatinine clearance and urinary protein excretion in patients with various renal diseases.

To investigate the effects of a change in posture on renal function, we measured Ccr and the urinary excretion of protein, albumin, immunoglobulin G (IgG) and transferrin in 80 patients with renal disease and in 9 healthy controls. Patients and controls were studied serially while supine for 60 min; then after standing upright for 60 min. Almost all subjects showed a drop in the Ccr with standing (p < 0.01). The percent change in Ccr after standing was more remarkable in patients with glomerulonephritis vs the healthy subjects (74.0 +/- 21.9% vs 89.9 +/- 12.3%, p < 0.01). The change in urinary excretion of protein and albumin after standing in patients with membranous nephropathy (MN-N) significantly exceeded that in patients with IgA nephropathy (IgA-N) (182.1 +/- 89.3% vs 108.1 +/- 59.2% in urinary protein and 181.7 +/- 98.7% vs 113.3 +/- 40.9% in urinary albumin, p < 0.01). Urinary excretion of IgG and transferrin tended to increase after standing in those two groups, but not significantly. Results indicate that posture affects urinary protein excretion, probably via an increase of glomerulocapillary hydrostatic pressure and/or change in the permeability of the glomerular capillary walls. We recommend that comparable postures should be used when protein excretion is used as a diagnostic tool and in monitoring structural damage to glomeruli, particularly in patients with membranous nephropathy.

Four cases of anti-myeloperoxidase antibody-related rapidly progressive glomerulonephritis during the course of idiopathic pulmonary fibrosis.

We report here 4 cases of rapidly progressive glomerulonephritis (RPGN) which developed during the management of idiopathic pulmonary fibrosis. In each patient, pulmonary disease preceded the onset of nephritis by 1 to 6 years. All patients had a high titer of serum autoantibodies against myeloperoxidase (MPO-ANCA) when the diagnosis of RPGN was made. Although the association of pulmonary fibrosis with ANCA-related glomerulonephritis has been occasionally described in the past literature, the sequence of pulmonary and renal injury has not been well defined. The present report demonstrates that idiopathic pulmonary fibrosis exists as a preceding condition in some patients with MPO-ANCA-related nephritis.

Case of propylthiouracil-induced vasculitis associated with anti-neutrophil cytoplasmic antibody (ANCA); review of literature.

A 39-year-old Japanese woman had been receiving propylthiouracil for 5 years for hyperthyroidism when she developed myalgia, scleritis, proteinuria, fever, and inflammation of the nose. Examination of a renal biopsy specimen showed focal segmental necrotizing glomerulonephritis. Indirect immunofluorescent staining showed a highly positive perinuclear pattern of anti-neutrophil cytoplasmic antibody (ANCA) in her serum. Enzyme-linked immunosorbent assay (ELISA) of the ANCA showed positivity for anti-proteinase 3, anti-myeloperoxidase, anti-leukocyte elastase, and anti-lactoferrin, but anti-cathepsin G and anti-lysozyme were negative. Because ELISA showed the titer of anti-leukocyte elastase antibody to be markedly elevated, we challenged this data by performing dot blot analysis. The patient's serum reacted with the native form, but not with denatured leukocyte elastase. Propylthiouracil-induced vasculitis was suspected. Symptoms abated within 2 weeks and all values of ANCA were reduced after the drug was withdrawn. Vasculitis is a rare side-effect of propylthiouracil therapy. Recently it was reported in association with ANCA. We present the findings of this patient and compare them with those described in 19 published cases of propylthiouracil-induced vasculitis associated with ANCA.

[Clinical analysis of 14 patients with anti-myeloperoxidase antibody positive rapid progressive glomerulonephritic syndrome].

We investigated the clinical features and outcome of 14 patients with anti-myeloperoxidase antibody (MPO-ANCA) positive rapidly progressive glomerulonephritic syndrome. Underlying diseases included microscopic polyarteritis in 6 patients, idiopathic crescentic glomerulonephritis with lung hemorrhage in 2 patients, idiopathic glomerulonephritis in 3 patients, rapidly progressive glomerulonephritic syndrome without renal biopsy in 1 patient, crescentic glomerulonephritis associated with Sjögren syndrome and progressive systemic sclerosis in 1 patient and crescentic glomerulonephritis associated with sarcoidosis in 1 patient. Five patients were male (mean age, 59.2 years) and 9 were female (mean age, 54.0 years). On admission, most patients had anemia, leukocytophilia, and marked elevation of C-reactive protein (CRP). Average hemoglobin, white blood cell count and CRP levels on admission were 8.1 mg/dl, 11,500/mm3 and 14.7 mg/dl, respectively. Average serum creatinine was 4.0 mg/dl. All patients were treated with steroids either with or without cyclophosphamide. As the patients recovered clinically, the MPO-ANCA titers declined. Although most patients responded well to immunosuppressive therapy, some died of serious complications (such as acute respiratory distress syndrome, fungal infection, and pneumocystis pneumonia). The prognosis of patients with severe renal failure was especially poor. We conclude that early diagnosis, treatment and intensive care during immunosuppressive therapy are very important in the management of MPO-ANCA-positive rapidly progressive glomerulonephritis.

Pro32Thr polymorphism of inosine triphosphate pyrophosphatase gene predicts efficacy of low-dose azathioprine for patients with systemic lupus erythematosus.

We evaluated the relationship between the efficacy of low-dose azathioprine (AZA) therapy and the inosine triphosphate pyrophosphatase (ITPA) 94C>A (Pro32Thr) polymorphism in patients with systemic lupus erythematosus (SLE). We performed a multiple regression analysis to assess the influence of various factors on the reduction in SLE disease activity index (SLEDAI) scores. The ITPA 94C>A polymorphism had the highest correlation with the change in SLEDAI score (r = 0.354, P = 0.006).

Nestin expression in the kidney with an obstructed ureter.

Nestin is an intermediate filament protein originally identified in neuroepithelial stem cells. This cytoskeletal-associated protein is also expressed in some non-neuronal organs including renal tubular cells and glomerular endothelial cells during kidney development. Little is known, however, about nestin expression in the kidney during injury. In this study, we find nestin expression induced in renal tubular and interstitial myofibroblasts in the adult rat kidney following unilateral ureteral obstruction. The degree of nestin expression was well correlated with the degree of tubulointerstitial fibrosis. Immunohistochemical identification of specific nephron segments showed that nestin was primarily expressed by proximal tubules, partially by distal tubules and thick ascending limbs of Henle but not by collecting ducts. The nestin-positive tubular cells also expressed vimentin and heat-shock protein 47 (HSP47) suggesting these cells reverted to a mesenchymal phenotype. Not all vimentin- or HSP-expressing cells expressed nestin; however, suggesting that nestin is distinct from these conventional mesenchymal markers. Nestin expression was also found associated with phenotypical changes in cultured renal cells induced by hypoxia or transforming growth factor-beta. Nestin expression was located in hypoxic regions of the kidney with an obstructed ureter. Our results indicate that nestin could be a novel marker for tubulointerstitial injury.

Increased intraplatelet and urinary transforming growth factor-beta in patients with multiple myeloma.

The concentrations of transforming growth factor-beta (TGF-beta) in platelets, plasma and urine from 27 patients with multiple myeloma (MM) and from 22 normal controls were measured by sandwich enzyme-linked immunosorbent assay using a monoclonal antibody specific for human TGF-beta 1+2+3. A significantly increased intraplatelet TGF-beta (24.6 +/- 9.6 vs. 17.8 +/- 8.8 ng/10(5) platelets, p < 0.01) and urinary TGF-beta (1.4 +/- 0.8 vs 1.0 +/- 0.4 ng/mg Cr, p < 0.02) were observed in MM patients compared with normal controls. The mean platelet TGF-beta level in MM patients with osteolytic lesions was more increased than in those without osteolytic lesions (29.6 +/- 7.7 vs 18.4 +/- 8.2 ng/10(5) platelets, p < 0.001). In this study, we evaluated the possible role of TGF-beta in the pathogenesis of myeloma, especially in osteolytic lesions.

FK506 inhibits renal glomerular thrombosis induced in rats by nephrotoxic serum and lipopolysaccharide.

We investigated the effect of the potent immunosuppressive agent, FK506, on experimental glomerular thrombosis in rats by combined injections of nephrotoxic serum (NTS) and lipopolysaccharide (LPS). Either FK506 or placebo was administered intramuscularly three hours prior to injection of NTS that was followed one hour later by LPS. Rats were killed five hours after the LPS injection. Compared with placebo, FK506 pretreatment significantly reduced thrombosis formation, in a dose-dependent manner. FK506 also reduced proteinuria and the rise of serum creatinine level. Early infiltration of polymorphonuclear leukocytes into the glomeruli after LPS injection was significantly suppressed in the FK506 group compared with the placebo group. We also measured serum tumor necrosis factor (TNF) activity by using an L929 fibroblast cytotoxicity assay. Peak serum TNF activity was observed one hour after LPS injection, and FK506 significantly suppressed the elevation. Thrombosis was also developed in athymic nude rats, suggesting thrombosis formation is T cell independent. These data suggest that the FK506 has inhibitory effects on non-lymphocytes and possesses an anti-inflammatory effect in vivo.