Prognostic Factors of Renal Involvement in Systemic Sclerosis

Background/Aims: Renal involvement is common in systemic sclerosis (SSc), including asymptomatic reduction of glomerular filtration rate (GFR), increased renal resistance indices, scleroderma renal crisis (SRC) and ANCA-associated vasculitis. The aim was to evaluate type and evolution of renal involvement for a period of five years. Methods: 121 SSc patients (100 F, 21 M) with mean age of 54.9 ± 13.8, disease duration of 9 ± 6 years, of which 62 had a diffused form and 59 limited form were enrolled. All patients were screened annually for renal function by laboratory examination, ultrasound and color Doppler ultrasound of renal arteries. Results: Over the five-year observation period, 6 SRC (3 M, 3 F) occurred, four of which required dialysis. One patient developed ANCA-related proliferative glomerulonephritis and the other one acute tubular necrosis. The remaining 113 patients had a preserved renal function (serum creatinine 0.75 ± 0.24 mg/dl, GFR 93.8 ± 20 ml/min, 24h proteinuria 0.20 ± 0.15 g). Doppler indices of intrarenal arterial stiffness increased with progression of capillaroscopic damage and with presence of digital ulcers. A negative correlation was observed between estimated GFR and pulsatile index (p< 0,05, r=-0.198), resistive index(p< 0,01, r=0.267), S/D ratio (p< 0,01, r=-0.237). Conclusion: In SSc patients, renal function was normal for 4.1 years despite the presence of increased intrarenal arterial stiffness. SRC was observed in 4.9% of SSc patients. In SSc patients, a periodic follow-up based on clinical and laboratory evaluation, colorDoppler ultrasound and, in some cases, renal biopsy is required to evaluate renal involvement

Intrarenal arterial stiffness is increased in systemic sclerosis patients with anti-ribonucleic acid polymerase III antibodies

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Evaluation of estimated glomerular filtration rate and clinical variables in systemic sclerosis patients

Objectives: The most important renal complication of systemic sclerosis (SSc) is scleroderma renal crisis (SRC). Many patients demonstrate less severe renal complications, most likely associated with reduced renal blood flow and a consequent reduction in glomerular filtration rate (GFR). The mechanism of this slowly progressive form of chronic renal disease is unclear. The aim of this study was to evaluate GFR by the Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) and the 7-variable Modification of Diet and Renal Disease (MDRD) equations in SSc patients and to correlate estimated GFR (eGFR) with clinical variables of the disease. Methods: 105 unselected and consecutive patients with SSc were enrolled. Serum creatinine was measured in all patients and GFR was estimated by 7-variable MDRD and CKD-EPI equations. Nailfold videocapillaroscopy was performed in all patients. Results: The mean value of eGFR evaluated by both 7-variable MDRD and CKD-EPI was significantly different (p < 0.0001) in the three capillaroscopic groups and correlated negatively with the severity of capillaroscopic damage (early: 95 ± 16 mL/min and 101 ± 12 mL/min, active: 86 ± 25 mL/min and 95 ± 17 mL/min, late: 76 ± 21 mL/min and 82 ± 21 mL/min). The mean value of eGFR evaluated by 7-variable MDRD (97 ± 23 mL/min vs. 74 ± 15 mL/min, p < 0.0001) and CKD-EPI (0.83 ± 0.20 mL/min vs. 0.68 ± 0.10 mL/min, p < 0.0001) was significantly higher in SSc patients without history of digital ulcers than in those with. Conclusion: We can conclude that in SSc patients without renal involvement, eGFR decreases with the progression of digital vascular damag

Hypothyroidism and nephrotic syndrome: why, when and how to treat

Hypothyroidism, characterised by low/normal free thyroxine (FT4) and free tri-iodothyronine (FT3) with elevated thyroid-stimulating hormone (TSH), is a well-known complication of nephrotic syndrome (NS). This is a common feature of primary and secondary glomerular diseases and comprises loss of protein in the urine and increased urinary excretion of thyroid hormones and thyroxine-binding globulin. With a normal thyroid reserve, this scenario is associated with the development of subclinical hypothyroidism, with a slight increase in TSH and normal free fractions. However, with a low thyroid reserve the transition toward overt hypothyroidism is almost inevitable, affecting morbidity and mortality. As T4 replacement is a cheap and well-established treatment to achieve a stable hormone status in different types of thyroid deficiency, it is essential to recognise and appropriately treat this condition. In this article we summarise the evidence on this nephro-endocrine disorder in humans and focus on diagnostic and therapeutic strategies

Angiogenic and angiostatic factors in renal scleroderma-associated vasculopathy

BACKGROUND: The angiogenesis in systemic sclerosis (SSc) is impaired. An imbalance of pro-angiogenic factors and angiogenesis inhibitors has been implicated in the progression of peripheral microvascular damage, defective vascular repair and fibrosis. Intrarenal resistance index are considered markers of renal vasculopathy. The aim of the study is to evaluate angiogenic and angiostatic factors (VEGF and endostatin) in SSc patients and to correlate with intrarenal hemodynamic parameters. METHODS: 91 SSc patients were enrolled in this study. Serum VEGF and endostatin levels were determined. All patients underwent a renal Doppler ultrasound RESULTS: A significant positive correlation was observed between endostatin and renal Doppler parameters (p<0.0001). A negative correlation was observed between serum levels of endostatin and eGFR (p<0.01). In SSc patients with high resistive index, serum levels of endostatin were significantly (p<0.01) higher than in SSc patients with normal resistive index. The serum levels of endostatin significantly increased with progression of nailfold videocapillaroscopy damage (p<0.01) and were significantly (p<0.05) higher in SSc patients with digital ulcers than in SSc patients without digital ulcers. CONCLUSION: This is the first study that assess in SSc patients intrarenal hemodynamic parameters and endostatin. In SSc patients, endostatin represents a marker of renal scleroderma-associated vasculopathy

Pharmacological effects of raas blockade in ischemic nephropathy

Background: The management of ischemic nephropathy due to atherosclerotic renal artery stenosis has become increasingly conservative in the modern era, with current guidelines recommending optimized medical therapy as the initial step. The doubts raised by the recently published trials of revascularization strategies have led to a renewed focus on pharmacological strategies promoting blood pressure control and renal protection. It is essential to further elucidate the pathophysiological mechanisms underlying hypoperfusion induced renal microvascular dysfunction with subsequent tissue injury and fibrogenesis. The role of renin angiotensin aldosterone system as a mediator of the main pathophysiological consequences of ischemic nephropathy is well known. However, more recent experimental evidence on the adrenergic system and intrarenal tubular feedback mechanisms has stimulated new interest towards a multi-target therapeutic approach. Methods: This review focuses on the pharmacology of the principle therapeutic drug classes currently used in the treatment of atherosclerotic renal artery stenosis with an analysis of their metabolic aspects and use in clinical practice based on evidence from clinical trials. Results and Conclusions: An optimal pharmacologic approach is crucial for a successful prevention of renal injury and cardiovascular events in this high-risk population. Antihypertensive treatment should include renin angiotensin aldosterone system blockade medication not only for their antihypertensive properties, but especially for those cardio and renoprotectiv

The involvement of T regulatory lymphocytes in a cohort of lupus nephritis patients: a pilot study

T regulator lymphocytes (Tregs) play a key role in the maintenance of immune tolerance and in the development of autoimmune diseases. Expression of Foxp3 is specific for Tregs, and can be used for the identification of these cells. This study investigated the variations of Tregs Foxp3? in the kidney biopsies inflammatory infiltrate of different lupus nephritis classes compared to that of ANCA glomerulonephritis, acute tubulointerstitial nephritis and nephroangiosclerosis. Sections of paraffin-embedded tissue have been stained by immunohistochemistry with anti-CD3 and anti-FoxP3 antibodies. We find that the ratio of FoxP3?/CD3? cells is significantly lower in patients with lupus nephritis class IV and in patients with vasculitides than in the course of nephroangiosclerosis, tubulointerstitial nephritis and lupus nephritis class V. The data presented herein demonstrate a decrease of FoxP3? Treg cells in the inflammatory infiltrate of lupus nephritis, particularly during the most active phases of lupus nephritis, as observed in the course of a IV class nephritis

Serum uric acid as a marker of microvascular damage in systemic sclerosis patients

Background: Microvascular damage of skin and internal organs is a hallmark of systemic sclerosis (SSc). Serum uric acid (UA) represents a marker of inflammation and endothelial dysfunction. The aims of this study were to evaluate the correlation between serum UA and intrarenal arterial stiffness evaluated by Doppler ultrasound in SSc patients with normal renal function. We also evaluated the correlation between serum UA and other clinical variables of the disease. Methods: Forty-five SSc patients underwent clinical assessment, Doppler ultrasound of intrarenal arteries with evaluation of resistive index (RI), pulsatile index (PI), and systolic/diastolic ratio (S/D), echocardiography with systolic pulmonary artery pressure (PAPs), baseline pulmonary function tests, and nailfold videocapillaroscopy (NVC). In all patients serum UA was measured. Results: The serum UA showed a significant positive correlation with sCr (r = 0.33, p &lt; 0.0001) and PAPs (r = 0.38, p &lt; 0.01) &gt; and negative correlation with CKD-EPI (r = -0.35, p &lt; 0.01). The mean value of serum UA increased with severity of NVC damage. Using this cut-off value of 4.7 mg/dl, the mean value of Doppler indices of intrarenal stiffness is significantly different (p &lt; 0.05) in SSc patients with low normal or high normal serum UA. Conclusions: Serum UA concentration is higher in patients with high microvascular damage than in patients with low microvascular damage. These preliminary data must be confirmed in large prospective studies

Left ventricular mass and intrarenal arterial stiffness as early diagnostic markers in cardiorenal syndrome type 5 due to systemic sclerosis

Background: Cardiorenal syndrome type 5 (CRS-5) includes a group of conditions characterized by a simultaneous involvement of the heart and kidney in the course of a systemic disease. Systemic sclerosis (SSc) is frequently involved in the etiology of acute and chronic CRS-5 among connective tissue diseases. In SSc patients, left ventricular mass (LVM) can be used as a marker of nutritional status and fibrosis, while altered intrarenal hemodynamic parameters are suggestive of early kidney involvement. Methods: Forty-two consecutive patients with a diagnosis of SSc without cardiac and/or renal impairment were enrolled to assess whether cardiac muscle mass can be related to arterial stiffness. Thirty subjects matched for age and sex were also enrolled as healthy controls (HC). All patients performed echocardiography and renal ultrasound. Results: Doppler indices of intrarenal stiffness and echocardiographic indices of LVM were significantly increased in SSc patients compared to HC. A positive correlation exists between LVM/body surface area and pulsatile index (p &lt; 0.05, r = 0.36), resistive index (p &lt; 0.05, r = 0.33) and systolic/diastolic ratio (p &lt; 0.05, r = 0.38). Doppler indices of intrarenal stiffness and LVM indices were significantly higher in SSc patients with digital ulcers than in SSc patients without a digital ulcer history. Conclusions: SSc is characterized by the presence of microvascular and multiorgan injury. An early cardiac and renal impairment is very common. LVM and intrarenal arterial stiffness can be considered as early markers of CRS onset. The clinical use of these markers permits a prompt identification of organ damage. An early diagnosis allows the appropriate setting of pharmacological management, by slowing disease progression

Atherosclerotic renal artery stenosis: one year outcome of total and separate kidney function following stenting

BACKGROUND: Renal artery stenosis (RAS) is a known cause of hypertension and ischemic nephropathy. Stenting of the artery is a valid approach, in spite of cases of unexpected adverse evolution of renal function. METHODS: In this study, 27 patients with unilateral RAS were subjected to stenting and followed for a period of one year, while 19 patients were observed while on medical treatment only. The group of 27 patients, 67.33 ± 6.8 years of age, creatinine of 2.15 ± 0.9 mg/dl, following stenting, were followed at intervals with biochemical tests, renal scintigraphy and doppler ultrasonography. The control group (70.0 ± 6.1 years, creatinine 1.99 ± 0.7 mg/dl) was also followed for one year. RESULT: One year after stenting mean creatinine clearance (Ccr) increased from 36.07 ± 17.2 to 40.4 ± 21.6 ml/min (NS). Arterial BP, decreased after 1,3,6, and 12 months (p < 0.05). The number of antihypertensive drugs also decreased (p < 0.05). A significant increase in proteinuria was also observed. In the control group both Ccr, BP and proteinuria did not show significant changes. Based on renal scintigraphy and Ccr at subsequent times, it was possibile to evaluate the timecourse of renal function in both kidneys of the stented patients. In the stented kidneys Ccr increased significantly. On the controlateral kidney a decrease of renal function (p < 0.05) was observed. Resistance index appeared to be a risk factor of the functional outcome. CONCLUSIONS: Stenting of RAS due to atherosclerosis is followed by stabilization or improvement of Ccr, mainly at the stented kidney, while contralateral renal function showed a decrease