A retrospective analysis for aetiology and clinical findings of 287 secondary amyloidosis cases in Turkey

Background. Secondary amyloidosis is the most frequent of the various types of systemic amyloidosis, the epidemiology of which is not yet fully known. The aim of our study was to evaluate retrospectively the collective data for the aetiological distribution, clinical findings and approaches to the management of secondary amyloidosis in Turkey. Methods. Data from a simple questionnaire addressing aetiology, and demographic and clinical characteristics of patients with biopsy-proven secondary amyloidosis was retrospectively analysed. Eleven nephrology clinics contributed data for this study. Results. The 11 contributing centres provided a total of 287 cases (102 female, 185 male). The aetiological distribution was as follows: familial Mediterranean fever (FMF) 64%, tuberculosis 10%, bronchiectasis and chronic obstructive lung disease 6%, rheumatoid arthritis 4%, spondylarthropathy 3%, chronic osteomyelitis 2%, miscellaneous 4%, unknown 7%. Oedema accompanied by proteinuria was present in 88% of the cases, hepatomegaly in 17%, and splenomegaly in 11%. The mean systolic and diastolic blood pressures were 115 +/- 26 and 73 +/- 15 mmHg respectively. The family history was positive in 16%; 73% of the cases were on colchicine treatment when the questionnaire was administered. Thirty-eight per cent of the cases had progressed to ESRD and were on renal replacement therapy. Conclusions. FMF is the leading cause of secondary amyloidosis in Turkey, followed by tuberculosis. Oedema accompanied by proteinuria is the most prominent presenting finding, and hypotension seems to be common among these patients

Chronic kidney disease is a key risk factor for severe COVID-19: a call to action by the ERA-EDTA

Diabetes, hypertension and cardiovascular disease have been listed as risk factors for severe coronavirus disease 2019 (COVID-19) since the first report of the disease in January 2020. However, this report did not mention chronic kidney disease (CKD) nor did it provide information on the relevance of estimated glomerular filtration rate (eGFR) or albuminuria. As the disease spread across the globe, information on larger populations with greater granularity on risk factors emerged. The recently published OpenSAFELY project analysed factors associated with COVID-19 death in 17 million patients. The picture that arose differs significantly from initial reports. For example, hypertension is not an independent risk factor for COVID-19 death [adjusted hazard ratio (aHR) 0.89], but renal disease very much is. Dialysis (aHR 3.69), organ transplantation (aHR 3.53) and CKD (aHR 2.52 for patients with eGFR<30mL/min/1.73 m(2)) represent three of the four comorbidities associated with the highest mortality risk from COVID-19. The risk associated with CKD Stages 4 and 5 is higher than the risk associated with diabetes mellitus (aHR range 1.31-1.95, depending upon glycaemic control) or chronic heart disease (aHR 1.17). In another recent publication, the Global Burden of Disease collaboration identified that worldwide, CKD is the most prevalent risk factor for severe COVID-19. Moreover, the distribution of risk factors for COVID-19 mortality appears to be different in patients with CKD when compared with the general population. The high prevalence of CKD in combination with the elevated risk of mortality from COVID-19 in CKD necessitates urgent action for this group of patients. This article defines essential action points (summarized in Box 1), among which is advocating the inclusion of CKD patients in clinical trials testing the efficacy of drugs and vaccines to prevent severe COVID-19

Evaluation of Sepsis/Systemic Inflammatory Response Syndrome, Acute Kidney Injury, and RIFLE Criteria in Two Tertiary Hospital Intensive Care Units in Turkey

Sepsis is a common cause of acute renal failure in intensive care units (ICU) with mortality rates as high as 60%. In this study, the clinical and laboratory predictors of acute kidney injury (AKI) in critically ill Turkish patients with sepsis/systemic inflammatory response syndrome were identified. We studied 139 (67 females/72 males) patients admitted to our ICUs with sepsis/systemic inflammatory response syndrome without renal failure. The clinical and laboratory parameters and treatments were recorded. Patients were classified as those without AKI (n = 60; 43.20%) and those with AKI (n = 79; 56.80%) based on the RIFLE (Risk, Injury, Failure, Loss, End-stage renal disease) criteria. Those with AKI were further classified as: risk in 27 (19%), injury in 25 (17.9%), failure in 25 (17.9%), and loss in 2 (1.4%). We found that the mortality rate increased with the severity of renal involvement: 56% in risk, 68% in injury, 72% in failure, and 100% in loss categories. Patients with AKI had a more positive fluid balance, higher central venous pressure, more vasopressor use, and lower systolic blood pressure. In multivariate analysis, the sequential organ failure assessment score, blood pressure, serum creatinine, and fluid balance were risk factors for the development of AKI. In this population, the incidence of AKI was higher and contrary to previous knowledge. A positive fluid balance also carries a risk for AKI and mortality in septic ICU patients. The RIFLE criteria were found to be applicable to our ICU population. Copyright (C) 2010 S. Karger AG, Base

Acute kidney injury in Turkey: epidemiological characteristics, etiology, clinical course, and prognosis

Background This study aimed to evaluate the etiologies, comorbidities, and outcomes of acute kidney injury (AKI) in Turkey and determine any potential differences among different geographical parts of the country. Methods This prospective observational study was conducted by the Acute Kidney Injury Working Group of the Turkish Society of Nephrology. Demographical and clinical data of patients with AKI at the time of diagnosis and at the 1(st) week and 1(st), 3(rd), and 6(th) months of diagnosis were evaluated to determine patient and renal survival and factors associated with patient prognosis. Results A total of 776 patients were included (54.7% male, median age: 67 years). Prerenal etiologies, including dehydration, heart failure, and sepsis, were more frequent than other etiologies. 58.9% of the patients had at least one renal etiology, with nephrotoxic agent exposure as the most common etiology. The etiologic factors were mostly similar throughout the country. 33.6% of the patients needed kidney replacement therapy. At the 6(th) month of diagnosis, 29.5% of the patients had complete recovery; 34.1% had partial recovery; 9.5% developed end-stage kidney disease; and 24.1% died. The mortality rate was higher in the patients from the Eastern Anatolian region; those admitted to the intensive care unit; those with prerenal, renal, and postrenal etiologies together, stage 3 AKI, sepsis, cirrhosis, heart failure, and malignancy; those who need kidney replacement therapy; and those without chronic kidney disease than in the other patients. Conclusion Physicians managing patients with AKI should be alert against dehydration, heart failure, sepsis, and nephrotoxic agent exposure. Understanding the characteristics and outcomes of patients with AKI in their countries would help prevent AKI and improve treatment strategies

Transforming growth factor-beta 1, vascular endothelial growth factor, and bone morphogenic protein-7 expression in tacrolimus-induced nephrotoxicity in rats

The aim of our study was to investigate transforming growth factor (TGF)-beta 1, vascular endothelial growth factor (VEGF), and bone morphogenic protein-7 (BMP-7) expression in the rat model of chronic tacrolimus (TAC) toxicity compared to healthy controls. Seventeen male Wistar rats were divided into two groups: group 1 animals were healthy controls and Group 2 animals were treated with TAC (1 mg/kg per day intraperitoneally for 8 weeks). At the end of the study period the animals were sacrificed following renal function studies including blood urea nitrogen (BUN), serum creatinine, and creatinine clearance, and renal tissues were examined by light microscopy for the findings of tacrolimus toxicity, specifically for afferent arteriolopathy and interstitial fibrosis. TGF-beta 1, VEGF, and BMP-7 expression were assessed by semiquantative scoring of the immunohistochemically stained specimens. Mean TAC levels were 5.53 +/- 2.38 ng/mL in group 2. BUN, creatinine levels, and creatinine clearance were 57.99 +/- 11.13 vs 39.49 +/- 5.64 mg/dL; 0.60 +/- 0.16 vs 0.65 +/- 0.09 mg/dL; 0.97 +/- 0.39 vs 1.17 +/- 0.32 mL/min in group 2 versus group 1. Only the BUN level was significantly higher in group 2 compared to group 1. Afferent arteriolopathy and interstitial fibrosis were significantly increased in group 2 compared to group 1. TGF-beta 1 and VEGF expression was significantly increased while BMP-7 expression was significantly decreased in group 2 versus group 1. In conclusion, our findings suggest that TAC-induced nephrotoxicity is associated with increased TGF-beta 1 and VEGF and decreased BMP-7 expression

The blockade of the renin-angiotensin system reverses tacrolimus related cardiovascular toxicity at the histopathological level

Introduction. In this study, we investigate the toxic effects of tacrolimus (FK506) on the cardiovascular system at the histopathological level in a rat model and whether these effects can be reversed by the blockade of the renin-angiotensin system (RAS) by either an angiotensin-converting enzyme inhibitor (ACE-inhibitors) or an angiotensin receptor antagonist (ARB). Methods and results. Thirty-one Wistar rats were divided into four groups. FK506 group was treated with FK506 intraperitoneally (i.p.), FK506+ACE-inhibitors and FK506+ARB groups were treated with either quinapril or valsartan orally in addition to FK506. Control group was treated with saline i.p. Histological and immunohistochemical staining of cardiovascular tissue in the FK506 group showed increased vacuolar degeneration (11.2 vs. 5.8, p=0.008), arterial hyalinosis (10.7 vs. 6.3, p=0.036), transforming growth factor-beta (TGF-P) (12.2 vs. 4.8, p=0.001) and vascular endothelial growth factor expression (VEGF) (10.7 vs. 6.3, p=0.036), elastic van Gieson (11.5 vs. 5.5, p=0.004), and periodic acid Schiff stain scores (12.5 vs. 4.5, p < 0.001) compared to the control group. Immunoihistochemical scores showed that expression of TGF-P is up-regulated, and bone morphogenic protein (BMP-7) is down-regulated with FK506 toxicity.Adding RAS blockade with either an ACE-inhibitor or an ARB could reverse FK506 induced changes. Both FK506+ACE-inhibitors and FK506+ARB groups demonstrated decrease in arterial hyalinosis (22.1 vs. 14.4 (FK5o6+ACE-inhibitor) and 13.6 (FK506+ARB), p=0.09) and vacuolar degeneration (23.1 vs. 16.1 (FK506+ACEinhibitor) and 12.4 (FK506+ARB), p=0.006) scores compared to the FK506 group. Conclusion. Blockade of RAS could reverse the histopathological signs of FK506 induced cardiac toxicity in a rat model

Evaluation of the angiotensin-converting enzyme insertion/deletion polymorphism and the risk of ischaemic stroke

Angiotensin-converting enzyme (ACE) gene polymorphism has been associated with increased incidence of stroke in some populations, although contradictory results have been reported. The aim of this study was to determine the allelic frequency and the genotypic distribution for ACE gene polymorphism in Turkish patients with ischemic stroke compared to appropriate healthy controls and to correlate the genetic findings with stoke type. One hundred and eight patients with ischemic stroke versus 79 healthy controls were studied for the presence of ACE gene polymorphism detected by PCR. Genotypes were defined as DD, II and ID according to the presence of the D (deletion) and I (insertion) alleles. There was no statistically significant difference in either the genotypic distribution or allelic frequency between the patients versus healthy controls (chi(2) = 0.105; df = 1; p = 0.430). There was also no significant difference for ACE genotype distribution and allelic frequency within the stroke group classified according to Bamford criteria (chi(2) = 4.827; df = 3; p = 0.185). Our data supports lack of association between DD genotype and/or D allele and ischemic stroke or subtypes of ischaemic stroke in the Turkish population. (c) 2006 Elsevier Ltd. All rights reserved

Inhibition of the renin angiotensin system decreases fibrogenic cytokine expression in tacrolimus nephrotoxicity in rats

The aim of our study was to investigate the influence of angiotensin-converting enzyme (ACE) inhibition and angiotensin II receptor blockage on the renal function by light microscopic and immunohistochemical findings in a rat model of tacrolimus nephrotoxicity. thirty-two male Wistar rats were divided into four groups of eight: G1 = control group; G2-G3, G4 = Tacrolimus (Tac) 1 mg/kg/d intraperitoneally (ip); G3 (Tac + Q) = ip Tac and peroral quinapril 10 mg/kg; and G4 (Tac + V) = Tac and valsartan 40 mg/d. Serum blood urea nitrogen (BUN), creatinine, and creatinine clearance were measured before and at the end of the study period. Renal tissues were assessed for light microscopic findings of tacrolimus toxicity. Transforming growth factor-beta, VEGF, PDGF, BMP-7, and interleukin-6 (IL-6) expression were semiquantitatively scored after immunohistochemical staining. At the end of the study period serum BUN and creatinine levels were increased in all groups, but creatinine clearance was not significantly changed between the groups. Afferent arteriolopathy was significantly less pronounced in G3 versus G2 and G4. Interstial fibrosis was significantly less pronounced in G3 and G4 versus G2. TGF-beta, PDGF, and IL-6 expression were significantly increased in G2, G3, and G4 compared to G1, and in G2 compared to G3 and G4. BMP-7 expression was significantly decreased in G2, G3, and G4 compared to G1, whereas the differences between G2, G3, and G4 failed to reach statistical significance. In conclusion, the results of our study suggested that renin angiotensin inhibition down-regulates fibrogenic cytokine expression in rats displaying tacrolimus nephrotoxicity