Vascular expression of annexin A2 in lupus nephritis

AIMS

To evaluate vascular expression of annexin A2 (ANXA2) and its subunit S100A10 in lupus nephritis (LN).

METHODS

The present histological study included 14 patients with LN and 11 controls (patients with non-lupus kidney diseases). Kidney biopsies from patients with lupus were scored for lupus glomerulonephritis (according to the International Society of Nephrology/Renal Pathology Society 2003 classification) and vascular lesions (such as microthrombi and antiphospholipid syndrome nephropathy (APSN)). ANXA2 and S100A10 expression in glomerular and peritubular capillaries was evaluated by immunohistochemistry on tissue sections. The staining intensity score ranged from 0 (no expression) to 4 (intense expression).

RESULTS

In patients with LN, the median age (range) at first kidney biopsy was 36 (18-49). Vascular lesions were observed in six patients (including two with APSN). We observed intense expression of ANXA2 in glomerular and peritubular capillaries while expression of S100A10 was weaker. However, one of the patients with APSN showed strong S100A10 expression. Patients with LN and controls differed significantly in terms of S100A10 expression in peritubular capillaries. We also observed a statistical difference between patients who had LN with renal vascular lesions and those without renal vascular lesions in terms of ANXA2 expression in peritubular capillaries.

CONCLUSIONS

The presence of vascular lesions in LN appears to be associated with significant differences in the vascular expression of ANXA2. Vascular expression of ANXA2 was somewhat higher in LN. Vascular expression of S100A10 was somewhat lower in LN (except one of the two patients with APSN). Further studies of ANXA2's putative value as a biomarker of active LN or of vascular lesions in LN are required.

Determinants of hydroxychloroquine blood concentration variations in systemic lupus erythematosus

OBJECTIVE

Blood concentrations of hydroxychloroquine (HCQ) vary widely among patients with systemic lupus erythematosus (SLE). A pharmacokinetic/pharmacodynamic relationship has been found in different situations, and a very low blood concentration of HCQ is a simple marker of nonadherence to treatment. Therefore, interest in blood HCQ concentration measurement has increased, but little is known about factors that influence blood HCQ concentration variability. This study was undertaken to analyze determinants of blood HCQ concentrations.

METHODS

We conducted a retrospective analysis of patient data, including data from the Plaquenil Lupus Systemic (PLUS) study, to determine the association of epidemiologic, clinical, and biologic factors with blood HCQ concentrations. Data for nonadherent patients (blood HCQ concentration <200 ng/ml) were excluded.

RESULTS

To examine homogeneous pharmacologic data, we restricted the analyses of the PLUS data to the 509 SLE patients receiving 400 mg/day. We found no association of ethnicity or smoking with blood HCQ concentrations and no pharmacokinetic drug-drug interaction with antacids or with inhibitors or inducers of cytochrome P450 enzymes. On multivariate analysis, high body mass index (P = 0.008), no treatment with corticosteroids (P = 0.04), increased time between the last tablet intake and measurement of blood HCQ concentrations (P = 0.017), low platelet count (P < 0.001), low neutrophil count (P < 0.001), and high estimated creatinine clearance (P < 0.001) were associated with low blood HCQ concentrations. In 22 SLE patients with chronic renal insufficiency (median serum creatinine clearance 52 ml/minute [range 23-58 ml/minute]) who received 400 mg/day HCQ, the median blood HCQ concentration was significantly higher than that in the 509 patients from the PLUS study (1,338 ng/ml [range 504-2,229 ng/ml] versus 917 ng/ml [range 208-3316 ng/ml]) (P < 0.001).

CONCLUSION

We provide a comprehensive analysis of determinants of blood HCQ concentrations. Because this measurement is increasingly being used, these data might be useful for clinicians.

Long-term effectiveness and safety of interleukin-1 receptor antagonist (anakinra) in Schnitzler's syndrome: a French multicenter study

The aim of this study is to assess the long-term effectiveness and safety of IL1Ra in Schnitzler syndrome (SchS). Between 2010 and 2012, we performed a nationwide survey among French internal medicine departments to identify SchS patients. We retrospectively analyzed the long-term efficacy and safety of IL1Ra and the outcome of patients that did not receive this treatment. Forty-two patients were included in the study, 29 of whom received IL1Ra. The mean age at disease onset was 59.9years. Disease manifestations included urticaria (100%), fever (76%), bone/joint pain (86%), bone lesions (76%), anemia (67%), and weight loss (60%). The monoclonal gammopathy was overwhelmingly IgM kappa (83%). The mean follow-up was 9.5years (range: 1.6-35). Two patients developed Waldenström's macroglobulinemia and one developed AA amyloidosis. All of the 29 patients who received IL1Ra responded dramatically. After a median follow-up of 36months (range: 2-79), the effectiveness remained unchanged. All patients remained on anti-IL-1 therapy. Twenty-four patients (83%) went into complete remission and five (17%) into partial remission. Three patients experienced grade 3-4 neutropenia. Six patients developed severe infections. No lymphoproliferative diseases occurred while on IL1Ra. When last seen, all patients without anakinra had an active disease with variable impact on their quality of life. Their median corticosteroids dosage was 6mg/d (range: 5-25). IL1Ra is effective in SchS, with a sharp corticosteroid-sparing effect. Treatment failures should lead to reconsider the diagnosis. Long-term follow-up revealed no loss of effectiveness and a favorable tolerance profile. The long-term effects on the risk of hemopathy remain unknown.

Gastrointestinal mucosal abnormalities using videocapsule endoscopy in systemic sclerosis

BACKGROUND

To date, there are no large studies on videocapsule endoscopy in systemic sclerosis (SSc). Consequently, the prevalence and features of gastrointestinal mucosal abnormalities in SSc have not been determined.

AIMS

To determine both prevalence and characteristics of gastrointestinal mucosal abnormalities in unselected patients with SSc, using videocapsule endoscopy. To predict which SSc patients are at risk of developing potentially bleeding gastrointestinal vascular mucosal abnormalities.

METHODS

Videocapsule endoscopy was performed on 50 patients with SSc.

RESULTS

Prevalence of gastrointestinal mucosal abnormalities was 52%. Potentially bleeding vascular mucosal lesions were predominant, including: watermelon stomach (34.6%), gastric and/or small intestinal telangiectasia (26.9%) and gastric and/or small intestinal angiodysplasia (38.5%). SSc patients with gastrointestinal vascular mucosal lesions more often exhibited: limited cutaneous SSc (P = 0.06), digital ulcers (P = 0.05), higher score of nailfold videocapillaroscopy (P = 0.0009), anaemia (P = 0.02), lower levels of ferritin (P < 0.0001) and anti-centromere antibody.

CONCLUSIONS

Our study identifies a high frequency of gastrointestinal mucosal abnormalities in SSc, with a marked predominance of vascular mucosal damage. Furthermore, our study shows a strong correlation between gastrointestinal vascular mucosal lesions and presence of severe extra-digestive vasculopathy (digital ulcers and higher nailfold videocapillaroscopy scores). This latter supports the theory that SSc-related diffuse vasculopathy is responsible for both cutaneous and digestive vascular lesions. Therefore, we suggest that nailfold videocapillaroscopy may be a helpful test for managing SSc patients. In fact, nailfold videocapillaroscopy score should be calculated routinely, as it may result in identification of SSc patients at higher risk of developing potentially bleeding gastrointestinal vascular mucosal lesions.

Lower vitamin D levels are associated with higher systemic lupus erythematosus activity, but not predictive of disease flare-up

Objectives

Growing evidence suggests that vitamin D plays a key role in the pathogenesis and progression of autoimmune diseases, including systemic lupus erythematosus (SLE). Recent studies have found an association between lower serum 25-hydroxyvitamin D (25(OH)D) levels and higher SLE activity. We studied the relationship between 25(OH)D levels and Systemic Lupus Erythematosus Disease Activity Index (SLEDAI) score, and we assessed for the first time the role of vitamin D in predicting SLE flare-ups.

Methods

Serum 25(OH)D levels were measured in 170 patients with SLE who were prospectively followed up for 6 months (Plaquenil LUpus Systemic study, ClinicalTrials.gov number NCT00413361).

Results

The mean SLEDAI score was 2.03±2.43 and 12.3% patients had active disease (SLEDAI ≥6). The mean 25(OH)D level was 20.6±9.8 ng/mL. Deficiency (25(OH)D <10 ng/mL) was observed in 27 (15.9%), insufficiency (10≤25(OH)D<30) in 112 (65.9%) and optimal vitamin D status (25(OH)D≥30) in 31 (18.2%) patients. In multivariate analysis, female gender (p=0.018), absence of defined antiphospholipid syndrome (p=0.002) and higher creatinine clearance (p=0.004) were predictive of lower 25(OH)D levels. In multivariate analysis, lower 25(OH)D levels were associated with high SLE activity (p=0.02). Relapse-free survival rate was not statistically different according to the vitamin D status during the 6-month follow-up (p=0.22).

Conclusions

We found a low vitamin D status in the majority of patients with SLE, and a modest association between lower 25(OH)D levels and high disease activity. There was no association between baseline 25(OH)D levels and relapse-free survival rate.

Multiple health care visits related to a pediatric emergency visit for young children with common illnesses

We aim to describe the number of health care visits before and after pediatric emergency department (PED) visits for common illnesses in a French tertiary pediatric hospital. This was a prospective cohort study with 501 children under 6 years of age who were evaluated and discharged from a tertiary care PED. Enrollment occurred on eight randomly selected study days between November 2010 and June 2011. The caregivers were then contacted via telephone 8 days later to obtain follow-up data, including information about return visits to health care facilities. Multiple visits were made by 206 (41 %) children, previous visits had occurred for 139 (28 %) children, and return visits had occurred for 94 (19 %) children. Previous and return visits were made at the PED as well as in general practitioners' offices and private pediatric offices. The median age of the subjects was 18 months. Fever was the most common complaint and was associated with more frequent multiple heath care visits.

CONCLUSION

Multiple heath care visits for the same illness are frequent, especially for febrile children. Interestingly, this phenomenon concerns every type of health care facility, including the PED, general practitioners' offices, and private pediatric offices. Further studies should be performed to achieve a better understanding of this phenomenon and to test specific interventions, such as parental education and improvement of the information system.

Antibodies against the N-terminal domain of annexin A2 in antiphospholipid syndrome

Annexin A2 (ANXA2, an endothelial cell receptor for plasminogen and tissue plasminogen activator) has been identified as a new autoantigen in antiphospholipid syndrome (APS). The aim of the present study was to evaluate the presence of antibodies against the N-terminal domain of annexin A2 (ANXA2) in primary APS (PAPS). By using a synthetic peptide corresponding to the 31N-terminal amino acids of ANXA2 (ANXA2(N31)) as an antigen, we performed an enzyme-linked immunosorbent assay (ELISA) to measure anti-ANXA2(N31) IgG and IgM antibodies in the serum of PAPS patients (n=19), systemic lupus erythematosus (SLE) patients (n=50) and healthy blood donors (n=106). We did not find any statistically differences between the three groups in terms of IgG and IgM anti-ANXA2(N31) titres. Elevated IgG anti-ANXA2(N31) titres were not observed in the serum of PAPS or SLE patients who had previously tested positive for anti-ANXA2 antibodies. Thus, the ANXA2 N-terminal domain does not appear to be the target antigen for anti-ANXA2 antibodies in APS.