Cognitive dysfunction and serum levels of brain-derived neurotrophic factor (BDNF) in primary anti-phospholipid syndrome (PAPS).

OBJECTIVES: Cognitive dysfunction (CD) is a poorly understood non-stroke central neurological manifestation in anti-phospholipid syndrome (APS). Brain-derived neurotrophic factor (BDNF) is a neurotrophin that plays an important role in neural plasticity and could potentially be a biomarker of CD in primary APS (PAPS). The aim of the study is to assess CD in PAPS patients and to evaluate its association with clinical data, anti-phospholipid antibodies and serum BDNF levels. METHODS: This cross-sectional study compared 44 PAPS patients and 20 healthy controls matched for age, gender and education. PAPS patients and controls underwent a standardized cognitive examination. The demographic, clinical and laboratory characteristics of patients were recorded. Serum BDNF was measured by Enzyme Linked Immunosorbent. RESULTS: Fourteen (31.8%) of the 44 patients with PAPS had CD compared with only one (5%) healthy control (P =0.019). PAPS patients presented lower serum BDNF levels when compared with controls (P =0.007). Lower levels of BDNF were associated with CD in PAPS patients (P =0.032). In the univariate analysis, a positive association was found between CD and livedo reticularis, deep vein thrombosis, stroke, seizure, smoking as well as a negative association with Mini Mental State Examination and serum BDNF. According to multivariate analysis, the only independent predictor of CD in PAPS was stroke (OR 137.06; 95% CI: 4.73, 3974.32; P =0.004). CONCLUSIONS: CD is commonly reported in PAPS patients; however, its assessment lacks in standards and objective screening tests. The association between CD and low serum BDNF suggests that this neurotrophin can be a promising biomarker for PAPS cognitive impairment.

Is serum uric acid a predictor of long-term renal outcome in lupus nephritis?

BACKGROUND/OBJECTIVE: Recent studies observed an association between increased serum uric acid (SUA) levels and renal damage in lupus. However, the predictive value of UA for the development of long-term renal dysfunction in lupus nephritis (LN) is still unknown. The aim of this study was to evaluate if SUA may be a predictor of long-term renal outcome in LN. METHODS: Eighty biopsy-proven LN patients > 7 years of follow-up were selected. SUA levels were measured in sera stored at - 70 °C. All patients had serum stored from LN baseline, and 32 also had stored serum from 6 and 12 months after LN. Renal outcome was addressed after 7 years of follow-up to determine if SUA could be a predictor of long-term renal outcome. A good long-term renal outcome in 7 years was defined as a creatinine clearance (CrCl) ≥ 90.0 mL/min/1.73 m2, and poor if CrCl < 90 mL/min/1.73 m2. Patients were divided in two groups according to the renal outcome to assess whether SUA levels at different time points of follow-up could differentiate such groups. An ROC curve was plotted to assess accuracy. RESULTS: SUA levels at baseline and 6 months were not able to differentiate good from poor long-term renal outcomes in LN (respectively p = 0.37, p = 0.28), but at 12 months (p = 0.02), they could clearly differentiate the two groups. ROC curve (12 months) accuracy was 0.76. SUA cutoff was 6.05 mg/dL (sensitivity = 0.67, specificity = 0.89, positive predictive value = 0.85, negative predictive value = 0.73). CONCLUSION: SUA levels < 6.05 mg/dL at 12 months of follow-up is a predictor of good long-term renal outcome in lupus nephritis. KEY POINTS: • Previous studies reported an association between increased serum uric acid level and short-term renal damage in lupus patients. • The predictive value of serum uric acid for the development of long-term renal dysfunction in lupus nephritis was never assessed. • At 12 months of follow-up serum uric acid clearly differentiated good from poor long-term renal outcome in lupus nephritis. • SUA level < 6.05 mg/dL at 12 months of follow-up was a predictor of good long-term renal outcome in lupus nephritis.

Extra-criteria manifestations of antiphospholipid syndrome: Risk assessment and management.

OBJECTIVES: Extra-criteria manifestations of antiphospholipid syndrome (APS) might impact on prognosis and morbidity of the disease. In this study, we aimed to evaluate a population of patients with primary APS (PAPS) whether the extra-criteria manifestations were more frequently found in subjects with higher adjusted Global APS Score (aGAPSS) values when compared to patients with thrombotic and/or obstetric APS ("criteria" manifestations) only. METHODS: Clinical records were analyzed to retrieve extra-criteria manifestation of APS, cardiovascular risk factors and antiphospholipid antibodies profile. The aGAPSS was calculated by adding the points, as follows: 3 for hyperlipidaemia, 1 for arterial hypertension, 5 for anticardiolipin antibodies IgG/IgM, 4 for anti-ß2 glycoprotein I IgG/IgM, and 4 for lupus anticoagulant. RESULTS: This retrospective multicenter study included 89 consecutive PAPS [mean age 43.1 (S.D. ± 12.9), female 67%, 52% arterial and 65% venous]. Twenty-seven patients (30.3%) had a history of livedo, 19 (21.3%) had a history of confirmed thrombocytopenia, 3 (3.4%) had biopsy-proven antiphospholipid antibodies (aPL)-related nephropathy and 3 (3.4%) had a history of valvulopathy. Patients with extra-criteria manifestations presented a mean aGAPSS significantly higher [mean 10.30 (S.D. ± 3.57, range: 4-17) vs mean 8.16 (S.D. ± 3.52;range: 4-16, p = 0.005). When comparing patients with and without extra-criteria manifestations, the first group had significantly higher incidence of anti-ß2GPI antibodies positivity (59% and 33%, respectively, p = 0.015), double aPL positivities (53% and 31%, respectively, p = 0.034), cerebrovascular events history (52% and 24%, respectively, p = 0.007) and arterial hypertension (52% and 24%, respectively, p = 0.007). CONCLUSIONS: Our results suggest that patients with higher aGAPSS, might be at higher risk for developing extra-criteria manifestations of APS and should therefore undergo a thorough laboratory and instrumental evaluation.

Serum uric acid levels are associated with lupus nephritis in patients with normal renal function.

Uric acid has been recognised as a potential marker of endothelial dysfunction and kidney disease but there are scarce data about its importance in systemic lupus erythematosus (SLE) nephritis. This study aimed to evaluate serum uric acid (UA) levels in lupus nephritis (LN), by comparing SLE patients with normal renal function, with and without nephritis. Forty-six female SLE patients were consecutively selected and divided in two groups according to renal activity at the evaluation: presence of a recently diagnosed lupus nephritis (LN+, n = 18) and absence of lupus nephritis (LN-, n = 28). Age-matched healthy women were selected (CONTROL, n = 28). Patients with gout, creatinine clearance lower than 80 ml/min and use of drugs that interfere in UA were excluded. Laboratory and clinical data were analysed by appropriate tests. A multivariate analysis was performed, and a receiver operating characteristic (ROC) curve was plotted, and the area under the curve was calculated to assess the diagnostic strength of UA in LN. The mean age was similar among LN+, LN- and CONTROL groups (32.44 ± 6.09 vs. 30.68 ± 5.36 vs. 30.86 ± 5.00 years, p = 0.52). UA was significantly higher in LN+ compared to LN- (5.54 ± 1.67 vs. 3.65 ± 1.090 mg/dL, p < 0.001) and CONTROL (5.54 ± 1.67 vs. 3.92 ± 0.95 mg/dL p < 0.001). Multivariate analysis confirmed that high UA was an independent variable related to LN (p < 0.001). The cut-off value for UA using the ROC curve was 4.47 mg/dL (AUC 0.86, p = 0.00004, CI 95% 0.75-0.96). Lupus nephritis was associated with higher UA. Hyperuricemia as a predictor of renal damage in SLE needs to be evaluated in further studies.