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BACKGROUND Amyloidosis is a protein-misfolding disease characterized by the deposition of aggregated proteins in the form of abnormal fibrils that disrupt tissue structure, ultimately causing disease. Amyloidosis is very frequent in untreated familial Mediterranean fever (FMF) patients and it is the most important feature that determines the prognosis of FMF disease. The mean platelet volume (MPV) in FMF has been previously studied. However, whether MPV level in FMF patients is lower or higher compared to healthy controls remains a topic of ongoing debate. In this study, we aimed to investigate MPV values and to assess the correlation between MPV and proteinuria in patients with AA amyloidosis and AA amyloidosis secondary to familial Mediterranean fever (AA-FMF) through a retrospective chart-review. MATERIAL AND METHODS This study was carried out on 27 patients with AA amyloidosis, 36 patients with AA amyloidosis secondary to FMF (a total of 63 patients with AA), and 29 healthy controls. There was no statistically significant difference between the AA patients and the control group (p=0.06) or between the AA-FMF group and the control group in terms of MPV values (p=0.12). RESULTS We found a statistically significant negative correlation between MPV and thrombocyte count in all groups (p<0.05 for all groups), but there was no correlation between MPV and proteinuria levels in AA patients (p=0.091). CONCLUSIONS While similar results also exist, these findings are contrary to the majority of previous studies. Therefore, further controlled clinical prospective trials are necessary to address this inconsistency.

Objective: AA amyloidosis occurs in the setting of longstanding inflammation. An increased incidence of coronary artery disease (CAD) was noted in patients with chronic inflammatory disease (CID). Retrobulbar blood flow predicts future macrovascular events including CAD. Increase in carotid artery intima-media thickness is regarded as a marker for early atherosclerosis. The relationship between chronic inflammation and atherosclerosis is well known; however, the connection between amyloidosis-advanced CIDs and retrobulbar microvascular function and carotid intima-media thickness (CIMT) is unidentified. We aimed to investigate whether retrobulbar microcirculation and CIMT were impaired or not in amyloidosis-advanced CID patients compared to normal subjects., Methods: Fourteen patients with renal AA amyloidosis and a group of healthy volunteers were included in the study. Measurement of CIMT and retrobulbar blood flow velocities was performed with ultrasound scanner and color Doppler ultrasonography., Results: The CIMT of patients with renal amyloidosis was significantly thicker than that of the normal population (p < 0.001). The resistivity index of the ophthalmic artery (OA) of patients with renal amyloidosis was significantly higher than the study group (p < 0.001)., Conclusion: This study demonstrates that accelerated atherosclerosis which can be shown by increased OA resistivity index and CIMT are found in amyloidal-related CID patients.

Aim: To investigate the nature of dyslipidemia and its diversity in patients with systemic AA amyloidosis., Methods: The reports of the kidney biopsies performed due to nephrotic proteinuria (>3.5 g/day/1.73 m(2)) with preserved renal function [glomerular filtration rate (GFR) >60 mL/min/1.73 m(2)] were reviewed. Clinical and laboratory data of the patients with systemic AA amyloidosis and primary glomerulonephritis (PG) were analyzed., Results: A total of 104 (systemic AA amyloidosis: 43, PG: 61) patients were included in the study. Proteinuria and GFR levels were similar in both the groups. Patients with systemic AA amyloidosis group had lower serum albumin (p = 0.002), lower hemoglobin levels (p = 0.001), higher platelet counts (p = 0.002) and higher C-reactive protein levels (p = 0.001) compared to patients in PG group. Although the frequency of dyslipidemia was similar in the groups (86.0 vs. 93.4%), patients with systemic amyloidosis had both lower values of LDL-C (4.56 ± 2.05 vs. 5.49 ± 2.23 mmol/L, p = 0.028) and HDL-C (1.19 ± 0.36 vs. 1.35 ± 0.39 mmol/L, p = 0.035). Serum lipid levels were correlated with serum total protein, albumin and proteinuria levels in PG group. However, in the systemic amyloidosis group, only one clear correlation between serum lipid and hemoglobin levels was estimated. A multivariate analysis demonstrated that LDL-C was independently associated with the etiology of nephrotic proteinuria, serum total protein, serum albumin (inversely) and hemoglobin levels., Conclusions: Although dyslipidemia is closely associated with serum total protein, albumin and proteinuria in patients with PG, there is no clear such association in patients with systemic amyloidosis. Correlation between serum lipid and hemoglobin levels in this group and other findings point out that probably complex mechanisms take place in dyslipidemia of nephrotic syndrome caused by systemic AA amyloidosis.

Autosomal dominant polycystic kidney disease (ADPKD) is an inherited disorder characterized by the development and growth of cysts in the kidneys. Non-nephritic-range proteinuria is a common presentation in ADPKD patients; however, nephrotic syndrome is a rare coincidence. A 52-year-old man is described who was diagnosed with secondary amyloidosis with ADPKD. To our knowledge, this is the first case of amyloidosis associated with frequently infected renal cysts. Patients with ADPKD who show massive proteinuria should be investigated in terms of concomitant glomerular disease.

Secondary amyloidosis is the most frequent form of the systemic amyloidosis around the world. Data on frequency and nature of dyslipidemia in patients with secondary amyloidosis are not conclusive. We evaluated the lipid abnormalities and their association with clinical and laboratory characteristics of the patients with secondary amyloidosis. The reports of the kidney biopsies performed in our hospital were reviewed. Clinical and laboratory data of the patients with biopsy-proven secondary amyloidosis were analyzed retrospectively. A total of 102 patients were diagnosed as having secondary amyloidosis. Familial Mediterranean fever was the leading cause of secondary amyloidosis accounting for 42.2 % of the cases. The most frequent indication for kidney biopsy was the nephrotic range proteinuria. The most common clinical and laboratory characteristics at the time of the diagnosis were edema, proteinuria and impaired renal function. The frequency of the nephrotic range proteinuria and microscopic hematuria were 75.5 and 18.6 %, respectively. Dyslipidemia was found in 88 % of the cases. Serum lipids significantly correlated with estimated glomerular filtration rate (eGFR), but not with serum albumin or urine protein levels. We demonstrated that majority of the patients with secondary amyloidosis had serum lipid abnormalities. Dyslipidemia was closely associated with GFR in a manner that patients with advanced stage kidney disease had lower serum lipid levels.

We report a patient with medullary sponge kidney (MSK) who presented with hematuria and nephrotic-range proteinuria. Renal biopsy revealed a diagnosis of renal AA amyloidosis. No secondary factors contributing to renal amyloidosis were demonstrated. To the best of our knowledge, this is the first reported case that demonstrates the coexistence of MSK and renal AA amyloidosis.

The resistance to erythropoietin, which is used to treat normochromic, normocytic anemia in chronic renal failure, can develop in patients with conditions such as iron deficiency, aluminum toxicity, hyperparathyroidism, chronic inflammatory diseases, and primary hematological disorders. We found amyloidosis in the bone marrow of a woman without any other etiology for erythropoietin resistance who was undergoing chronic hemodialysis. Her anemia did not improve, despite 6 months of erythropoietin therapy. Bone marrow amyloidosis was found to be the reason for erythropoietin-resistant anemia in our patient with chronic renal failure and renal anemia. We present the case of bone marrow amyloidosis because it is a very rare cause of erythropoietin resistance.

AA amyloidosis is a relatively rare disease which complicates chronic inflammatory diseases, chronic infections, familial Mediterranean fever (FMF) and malignant diseases. Although amyloid deposition may be found in many organs, renal involvement dominates the clinical picture. We reviewed 63 patients with AA amyloidosis who presented to our nephrology department between 1995 and 2000. Prognostic markers, detailed history, physical examination and laboratory tests were evaluated. The causes of AA amyloidosis were as follows: FMF 42 (66.6%), pulmonary tuberculosis 9 (14.2%), chronic osteomyelitis 4 (6.3%), bronchiectasia 4 (6.3%), rheumatoid arthritis 1 (1.5%), juvenile idiopathic arthritis 1 (1.5%), inflammatory abdominal aortic aneurysm 1 (1.5 %), unknown aetiology 1 (1.5%). The diagnosis was made on renal biopsies in 63.4% of the patients, while the remaining 36.6% were diagnosed as a result of rectal biopsies. Sixteen patients died. A low serum albumin, high creatinine and high 24-hour urine albumin excretion were associated with high mortality.

Secondary amyloidosis (AA amyloidosis) is a well known cause of nephrotic syndrome and renal failure. Several studies in patients with nephrotic syndrome have suggested a beneficial effect of angiotensin-converting enzyme inhibitors (ACEI). Angiotensin II (ATII) receptor antagonists effect on the long term is not known. In this study, we intended to study the effect of losartan, as an ATII receptor antagonist, on proteinuria and renal functions in patients with normotensive secondary amyloidosis. In total 44 patients with biopsy proven AA amyloidosis associated with nephrotic proteinuria were included. The first group of patients (n=22) was treated with losartan 50 mg/day. The second group of patients (n=22) did not receive any specific antiproteinuric treatment. Urinary protein loss was effectively lowered by losartan from 4.38 +/- 1.0 to 2.8 +/- 0.61 g/day (p<0.0001), whereas the control group showed a slight fall in proteinuria as 4.21 +/- 1.06 to 4.12 +/- 1.07 g/day (p = 0.176). Hypoalbuminemia improved significantly from 2.52 +/- 0.69 to 2.78 +/- 0.46 g/dl (p = 0.004), in the losartan group, whereas serum albumin had fallen in the control group from 2.44 +/- 0.57 to 2.27 +/- 0.41 (p = 0.041). Serum creatinine increased in the control group from 1.52 +/- 0.42 to 2.39 +/- 0.51 mg/dl (p<0.0001), and in the losartan group from 1.59 +/- 0.50 to 1.84 +/- 0.6 mg/dl (p<0.001), after 24 months of treatment. The ATII receptor blocker losartan is effective in protecting against the progression of nephropathy due to AA amyloidosis. Symptomatic treatment of proteinuria with losartan is therefore to be considered, especially with severe proteinuria even in normotensive patients.