Circumferential Strain as a Marker of Vessel Reactivity in Patients with Intradialytic Hypotension.

Background and Objectives: Intradialytic hypotension (IDH) complicates 4 to 39.9% of hemodialysis (HD) sessions. Vessels' reactivity disturbances may be responsible for this complication. Two-dimensional speckle tracking is used to assess arterial circumferential strain (CS) as a marker of the effectiveness of the cardiovascular response to the reduction of circulating plasma. Materials and Methods: The common carotid artery (CCA) and common iliac artery (CIA) CSs were recorded using ultrasonography in 68 chronically dialyzed patients before and after one HD session. Results: In patients with IDH episodes (n = 26), the CCA-CS was significantly lower both before (6.28 ± 2.34 vs. 4.63 ± 1.74 p = 0.003) and after HD (5.00 (3.53-6.78) vs. 3.79 ± 1.47 p = 0.010) than it was in patients without this complication. No relationship was observed between CIA-CS and IDH. IDH patients had a significantly higher UF rate; however, they did not differ compared to complication-free patients either in anthropometric or laboratory parameters. Conclusions: Patients with IDH were characterized by lower pre- and post-HD circumferential strain of the common carotid artery. The lower CCA-CS showed that impaired vascular reactivity is one of the most important risk factors for this complication's occurrence.

Post-transplant manifestation of ankylosing spondylitis: a case report and review of literature.

BACKGROUND: Ankylosing spondylitis (AS) is an insidiously progressive and debilitating form of arthritis involving the axial skeleton, characterized by chronic back pain and progressive spinal stiffness, and lessening of pain and stiffness with exercise. Due to subsequent manifestation in different organs, AS causes reduction in life expectancy, so early diagnosis and treatment are of great importance. No AS cases have been reported in solid-organ transplant recipients yet. CASE PRESENTATION: A 58-year-old woman with end-stage renal disease due to chronic glomerulonephritis, after allogenic kidney transplantation 25 years earlier, with stable, good graft function, treated with chronic immunosuppressive therapy based on cyclosporine A, mycophenolate mofetil, and prednisone, with no previous history of a connective tissue disease presented fever up to 39 °C accompanied by pain localized in sacroiliac region radiating to the left lower limb. Detailed diagnostic procedures and x-rays of the lumbar spine and of the targeted sacroiliac joints revealed lesions characteristic of AS. Sulphasalazine was added to standard immunosuppression regimen with good clinical results. CONCLUSIONS: We report an adult kidney transplant recipient with a new onset of AS. The risk of relapse or new onset of inflammatory disease in transplant recipients is extremely low due to immunosuppressive therapy following transplantation. However, when it occurs, the clinical presentation is commonly atypical, often leading to delayed diagnosis.

The pattern of overnight changes in novel markers of acute kidney injury in patients with obstructive sleep apnea.

BACKGROUND: Obstructive sleep apnea (OSA) may predispose patients to acute kidney injury (AKI) and chronic kidney disease (CKD). OBJECTIVES: We postulated that apneic episodes during sleep in patients with OSA may result in episodes of subclinical AKI that may be detected by the use of novel sensitive serum and urine markers. The treatment of OSA may protect against renal injury. MATERIAL AND METHODS: The study involved 86 men who had positive screening test results for OSA and estimated glomerular filtration rates (eGFR) calculated with the Chronic Kidney Disease Epidemiology Collaboration (CDK-EPI) equation >60 mL/min/1.73 m². All the patients underwent overnight polysomnography (the diagnostic night). The patients were divided into 2 groups: 45 patients with mild OSA and 41 patients with moderate-to-severe OSA. Those in the latter group were qualified for 6-8 weeks of continuous positive airway pressure (CPAP) treatment. Blood pressure, serum creatinine, high sensitivity C-reactive protein (hsCRP), urine creatinine, AKI markers cystatin C and neutrophil gelatinase-associated lipocalin (NGAL), kidney injury molecule 1 (KIM-1), liver-type fatty acid-binding protein, and endothelium marker intercellular adhesion molecule-1 (ICAM-1) were assessed in both groups before and after polysomnography. The same parameters were also measured in the patients with moderate-to-severe OSA after CPAP therapy. RESULTS: Kidney injury molecule 1 and urine NGAL significantly increased after the diagnostic night in the whole group and in mild OSA patients (p = 0.04 and p = 0.001, respectively). Serum ICAM-1 significantly decreased after the diagnostic night only in mild OSA patients (p = 0.03. Urine cystatin C increased after 6-8 weeks of CPAP treatment in the moderate-to-severe OSA group (0.003). Serum ICAM-1 decreased after the CPAP treatment (p = 0.02). The CPAP therapy led also to a decrease in mean and diastolic (p = 0.005) blood pressure. CONCLUSIONS: The pattern of overnight changes in serum and urine AKI markers after apneic episodes during sleep may suggest an increased risk of subclinical AKI in patients with OSA. The CPAP therapy is not protective against AKI, but may reduce some of its risk factors, including high blood pressure and endothelial damage.

Acute Kidney Injury Following Exposure to Calcineurin Inhibitors in a Patient with Idiopathic Membranous Nephropathy.

Membranous nephropathy (MN) is one of the most common causes of nephrotic syndrome in non-diabetic adult patients; 75% of adult patients with MN suffer from primary idiopathic membranous nephropathy (IMN). The treatment of choice is immunosuppressive therapy, with a combination of steroids and cyclophosphamide (CYF) or chlorambucil or, as second-line treatment, calcineurin inhibitors (CNIs). One of the main concerns associated with the usage of CNIs is their potential to induce nephrotoxicity. We report a case of acute kidney injury that developed on two separate occasions within days of the administration of CNIs in a 57-year-old male patient treated for MN. The patient was qualified for first-line treatment with prednisone and CYF. Due to insufficient response and bad tolerance of CYF infusions, the immunosuppressive regimen was modified and CNIs were introduced, starting with cyclosporine A (CsA). On the third day of treatment, a severe decrease in diuresis and kidney function occurred and CsA was discontinued, resulting in a return to baseline kidney function. After 2 months, the situation repeated after attempting to introduce tacrolimus.

Tacrolimus: Influence of the Posttransplant Concentration/Dose Ratio on Kidney Graft Function in a Two-Year Follow-Up.

INTRODUCTION: Tacrolimus (TAC) metabolism rate has the potential to impact graft function after kidney transplantation (KTx). We aimed to analyze the relationship between the early post-KTx TAC C/D ratio (blood trough concentration normalized by total daily dose) and kidney graft function in a 2-year follow-up. METHODS: We retrospectively analyzed data from 101 post-KTx patients at 3, 6, 12, and 24 months after KTx to identify the C/D ratio cutoff value optimal for dividing patients into fast and slow TAC metabolizers. We investigated the relationship between their TAC metabolism rate and graft function. RESULTS: Patients were divided based on the TAC C/D ratio at 6 months after KTx of 1.47 ng/mL * 1 mg. Fast metabolizers (C/D ratio <1.47 ng/mL * 1 mg) presented with significantly worse graft function throughout the whole study period (p < 0.05 at each timepoint) and were significantly less likely to develop good graft function (estimated glomerular filtration rate ≥45 mL/min/1.73 m2) than slow metabolizers. Our model based on donor and recipient age, recipient sex and slow/fast metabolism status allowed for identification of patients with compromised graft function in 2-year follow-up with 66.7% sensitivity and 94.6% specificity. CONCLUSION: Estimating TAC C/D ratio at 6 months post-KTx might help identify patients at risk of developing deteriorated graft function in a 2-year follow-up.