Sickle cell disease: a case report of renal amyloidosis.

BACKGROUND: The development of proteinuria and reduced glomerular filtration rate is associated with higher mortality among patients with sickle cell disease (SCD). AA amyloidosis, also associated with increased mortality, in SCD is rare. We present a case of a woman with homozygous sickle cell disease with nephrotic syndrome and antibodies to double stranded DNA without clinical features of systemic lupus erythematosus. Kidney biopsy reveals AA amyloidosis and is the first report of concomitant AA amyloidosis with antibodies to double stranded DNA in SCD. CASE PRESENTATION: A 40-year-old Central African woman with homozygous sickle cell disease and history of vaso-occlusive pain crises undergoes kidney biopsy for nephrotic-range proteinuria. Kidney biopsy reveals AA type amyloidosis, which is a rare manifestation of SCD in the kidney. Her anemia worsens with an ACE inhibitor, initiated to reduce proteinuria and limit GFR decline, so it was discontinued. Hydroxyurea, shown to decrease the frequency of vaso-occlusive crises and lower proteinuria, was subsequently initiated but then discontinued due to worsening anemia. Unfortunately, her glomerular filtration rate worsens. CONCLUSIONS: AA amyloidosis and antibodies to double stranded DNA can occur in sickle cell disease. ACE inhibition and hydroxyurea decrease proteinuria so they may limit progression of chronic kidney disease. Hydroxyurea also decreases frequency of vaso-occlusive pain crises so it might be helpful in limiting progression of renal AA amyloidosis. However, further studies are needed to determine optimal treatment strategies for AA amyloidosis in sickle cell disease.

A patient with AL amyloidosis with negative free light chain results.

The detection and quantification of amyloidogenic monoclonal light chains are necessary for the diagnosis and evaluation of response to treatment in AL amyloidosis. However, the amyloid clone is often small and difficult to detect. We report the case of a 68-year-old man who was referred to our Center in April 2013 after syncope and the identification of left ventricular hypertrophy at echocardiography, suspected for amyloidosis. A commercial agarose gel electrophoresis immunofixation (IFE) did not reveal monoclonal components in serum and urine. The κ serum free light chain (FLC) concentration was 21.5 mg/L, λ 33 mg/L (κ/λ ratio 0.65), NT-proBNP 9074 ng/L (u.r.l. <332 ng/L) and an echocardiogram confirmed characteristic features of amyloidosis. The abdominal fat aspiration was positive and the amyloid typing by immune-electron microscopy revealed λ light chains deposits. A high-resolution (hr) IFE of serum and urine showed a faint monoclonal λ component in the urine. A bone marrow biopsy showed 8% plasma cells (BMPC) and a kappa/lambda light-chain restriction with λ light chain on immunofluorescence. The diagnosis of AL (λ) amyloidosis with cardiac involvement was made. In May 2013, patient was started on cyclophosphamide, bortezomib and dexamethasone. After six cycles, serum and urine hr-IFE were negative, the bone marrow biopsy showed 3% BMPC without light chain restriction by immunofluorescence, and a decrease of NT-proBNP was observed (5802 ng/L).Thus, treatment was discontinued. In this patient the amyloid clone could be detected only by in house hr-IFE of urine and bone marrow examination. The detection of the small dangerous amyloidogenic clone should be pursued with a combination of high-sensitivity techniques, including assessment of BMPC clonality. Studies of novel tools, such as mass spectrometry on serum and next-generation flow cytometry analysis of the bone marrow, for detecting plasma cell clones in AL amyloidosis and other monoclonal light chain-related disorders are warranted.

Serum galectin-3 levels were associated with proteinuria in patients with Familial Mediterranean Fever.

BACKGROUND: The most common and pernicious complication of Familial Mediterranean fever (FMF) is renal amyloidosis, usually affecting the kidneys, leading to end-stage renal failure. FMF-related renal amyloidosis needed to be diagnosed early. Optimal colchicine dose is effective in preventing and reversing renal amyloidosis. Galectin-3, profibrotic mediator, has regulatory functions in inflammation, fibrosis and tumorigenesis. Galectin-3 is a strong prognostic marker for heart failure. Galectin-3 plays role in diabetic nephropathy and chronic kidney disease. The aim of the study is to investigate whether galectin-3 is related to proteinuria and amyloidosis in FMF. METHODS: Seventy-five FMF patients who have no exclusion criteria and healthy controls (n = 36) were included. Serum galectin-3 was measured and morning spot urine was collected for determination of the protein/creatinine ratio (PCR). RESULTS: Serum Galectin-3 levels were significantly higher in FMF patients than the control group [969.66 (3825) pg/mL vs. 238 (921) pg/mL, respectively; P<0.001]. We classified into two groups: Group1 (n = 48) had FMF patients with proteniuria, Group2 (n = 27) had FMF patients without proteinuria. Group1 had higher levels of galectin-3 than Group2 [1106(3812) pg/mL vs. 867.3(1433) pg/mL, P < 0.001]. Galectin-3 levels were correlated with PCR in whole group and FMF group (r = 0.785, P < 0.001 and r = 0.803, P < 0.001). In ROC curve, best cutoff value = 581.50 pg/mL was used to detect proteinuria (sensitivity = 91.7 %, specificity = 71.4 %, AUC = 0.879) and optimal cutoff value = 1458.00 pg/mL was an indicator of nephrotic-range proteinuric (sensitivity = 100 %, specificity = 92.1 %, AUC = 0.983). CONCLUSION: Galectin-3 is associated with proteinuria and renal amyloidosis in FMF. Galectin-3 may play role in pathogenesis of amyloidosis.

Urinary excretion of nephrin in rheumatoid arthritis patients with proteinuria.

OBJECTIVES: To investigate urine excretion of nephrin in patients with proteinuric nephropathies associated with rheumatoid arthritis (RA). METHODS: We enrolled in the study 42 patients with seropositive RA and proteinuria, the control group (20 persons) was formed from healthy blood donors, the comparison group (23 persons) was formed from RA patients without proteinuria. Kidney biopsy was performed in 26 patients (glomerulonephritis was diagnosed in 14 patients, АА-amyloidosis in 7 patients and tubulointerstitial nephritis in 5 patients). RESULTS: Urine nephrin concentration in patients with RA and proteinuria was 6.2 (3.0; 8.8) ng/ml and significantly differed in its levels both in controls - 3.6 (2.4; 5.3) ng/ml (p=0.03) and RA patients without proteinuria - 3.2 (2.1; 5.1) ng/ ml (p=0.015) group. In RA patients with proteinuria, we found a positive correlation between urine nephrin and protein concentrations (r=0.4; p=0.04). Urine nephrin levels in patients of the glomerulonephritis - 7.3 (5.9; 9.2) and amyloidosis groups - 6.9 (3.9; 9.8) ng/ml were higher than in the controls (p=0.001; p=0.04) and in the group of patients without proteinuria (p=0.005; p=0.03). In the patients with tubulointerstitial nephritis urine nephrin concentration did not differ significantly with the values in both the control and the RA patients without proteinuria groups. CONCLUSIONS: According to our data, proteinuria in the overall cohort of patients with seropositive RA is associated with increased levels of urine nephrin excretion, the highest levels of nephrin excretion were registered in patients with glomerulonephritis and amyloidosis.

Do neutrophil gelatinase-associated lipocalin and interleukin-18 predict renal dysfunction in patients with familial Mediterranean fever and amyloidosis?

BACKGROUND: The aim of this study was to evaluate whether neutrophil gelatinase-associated lipocalin (NGAL) and interleukin-18 (IL-18) predict renal disfunction in patients with familial Mediterranean fever (FMF). METHODS: This prospective study consisted of 102 patients with FMF in attack-free period, and 40 matched healthy controls. Of the patients, nine were diagnosed as amyloidosis. The patients were divided into two groups according to eGFR as below 120 mL per minute and above 120 mL per minute. Also, patients were divided into three groups according to the degree of urinary albumin excretion as normoalbuminuric, microalbuminuric, and macroalbuminuric. The serum levels of IL-18 (sIL-18) and NGAL (sNGAL), and urinary levels of IL-18 (uIL-18) and NGAL (uNGAL) were measured by using ELISA kits. RESULTS: The levels of sIL-18, sNGAL, uIL-18, and uNGAL were detected significantly higher in FMF patients, particularly in patients with amyloidosis, when compared to controls. sNGAL, uIL-18, and uNGAL were significantly higher in patients with eGFR < 120 mL per minute than in patients with eGFR ≥ 120 mL per minute. sNGAL, uIL-18, and uNGAL were correlated significantly with urinary albumin excretion, additionally, were inverse correlated with eGFR. The most remarkable findings of this study are of the higher values of sIL-18, sNGAL, uIL-18, and uNGAL in both normoalbuminuric FMF patients and patients with eGFR ≥ 120 mL per minute. CONCLUSIONS: The results of this study suggest that sIL-18, uIL-18, sNGAL, and uNGAL are reliable markers of early renal disfunction in FMF patients, and may let us take measures from the early stage of renal involvement.

"Idiopathic Bence-Jones proteinuria": a new characterization of an old entity.

Idiopathic Bence-Jones proteinuria (BJP) is a rare plasma cell dyscrasia, of which the clinical and biological characteristics are yet unclear. Historical data suggested that they are at higher risk of progression to multiple myeloma or other related neoplasms, while recent findings are contradictory. To address these open questions, we evaluated a series of both BJP and monoclonal gammopathy of undetermined significance (MGUS) with production of an intact immunoglobulin plus Bence-Jones proteinuria (MGUS+BJP) with long-term follow-up, regarding their clinical characteristics and progression to multiple myeloma, amyloidosis or other related B cell lymphoproliferative disorders. Two hundred and twenty-nine persons fulfilling the 2004 criteria of MGUS were included in the final analyses: 31 had BJP and 198 had MGUS+BJP. At the time of diagnosis, significantly more persons in the BJP group had renal impairment, anaemia and polyneuropathy. A more detailed analysis revealed discrepancies between the serum and urine light chain type in nine cases, reflecting clonal heterogeneity. The number of disease progressions was higher in MGUS+BJP (n = 30) when compared to BJP (n = 1), with a rate of 1.6 and 0.4 progressions per 100 person-years, respectively. In conclusion, BJP has distinct clinical characteristics and a lower risk of progression when compared to MGUS+BJP. Our data suggest that MGUS+BJP being closer to malignant transformation may be due to the higher portion of genetically heterogeneous, pre-malignant plasma cell subclones.

Urinary cytopathology in primary bladder amyloidosis.

BACKGROUND: Amyloidosis results from the accumulation of unique extracellular proteins which are not able to be degraded via the usual mechanism of lysosomal proteolysis. Isolated collections of amyloid within the bladder are extremely uncommon, and a cytopathologic description in voided urine has not been described to date. METHODS: A retrospective review was performed at a tertiary-care hospital, and 3 patients with isolated bladder amyloidosis and corresponding voided urine specimens were identified. The following clinical data were collected for each case: age, gender, treatment and follow-up information. RESULTS: The patient age range was 76-84 years, with 2 males and 1 female. Amyloidosis was never clinically suspected. In 1 patient, a urinary amyloid manifested, which was thought to represent extraneous debris at the time of original diagnosis. Two patients never manifested signs of systemic amyloidosis or multiple myeloma, and the third was found to have a monoclonal gammopathy. CONCLUSIONS: Our results show the difficulty of diagnosing urinary amyloid in the absence of clinical suspicion. Further, the presence of urinary amyloid is unlikely in patients with bladder amyloidosis as the cohesive nature of the protein makes spontaneous shedding uncommon. Testing for systemic amyloidosis is warranted and if the disease is localized, a favorable outcome can be expected.

Effect of lysine modification on the stability and cellular binding of human amyloidogenic light chains.

AL amyloidosis is characterized by the pathologic deposition as fibrils of monoclonal light chains (i.e., Bence Jones proteins [BJPs]) in particular organs and tissues. This phenomenon has been attributed to the presence in amyloidogenic proteins of particular amino acids that cause these molecules to become unstable, as well as post-translational modifications and, in regard to the latter, we have investigated the effect of biotinylation of lysyl residues on cell binding. We utilized an experimental system designed to test if BJPs obtained from patients with AL amyloidosis or, as a control, multiple myeloma (MM), bound human fibroblasts and renal epithelial cells. As documented by fluorescence microscopy and ELISA, the amyloidogenic BJPs, as compared with MM components, bound preferentially and this reactivity increased significantly after chemical modification of their lysyl residues with sulfo-NHS-biotin. Further, based on tryptophan fluorescence and circular dichroism data, it was apparent that their conformation was altered, which we hypothesize exposed a binding site not accessible on the native protein. The results of our studies indicate that post-translational structural modifications of pathologic light chains can enhance their capacity for cellular interaction and thus may contribute to the pathogenesis of AL amyloidosis and multiple myeloma.

Acute kidney injury during leukocyte engraftment after autologous stem cell transplantation in patients with light-chain amyloidosis.

Engraftment syndrome (ES) is a complication of hematopoietic stem cell transplantation characterized by fever, rash, and non-cardiogenic pulmonary edema. Acute kidney injury (AKI) has been recognized but is considered a minor criterion in one and excluded another definition of ES. We have noted a high incidence of AKI in patients with immunoglobulin light-chain amyloidosis (AL) undergoing autologous stem cell transplant (ASCT) around the time of leukocyte engraftment. This study was conducted to further investigate the relationship between AKI and ES. Data were collected from 377 AL patients who underwent ASCT from 7/1997 to 10/2009. Patients who experienced an elevation of serum creatinine >0.5 mg/dL within 4 days of leukocyte engraftment and anyone who presented with signs associated with ES regardless of renal manifestations were included. Forty-one patients met criteria. Twelve were excluded for positive cultures (10), acute interstitial nephritis (1), and acute cellular rejection (1). In addition to AKI (93.1%), patients also exhibit fever (82.7%), hypotension (51.7%), rash (48.2%), edema (93.1%), diarrhea (69.0%), conjunctival hemorrhage (31.0%), pulmonary edema (31.0%), pulmonary hemorrhage (13.8%), and transient encephalopathy (17.2%). Patient with pulmonary involvement were more likely to require dialysis but was not statistically significant. AKI was very common during leukocyte engraftment in AL patients. While infectious etiology accounted for some of the AKI, most appeared to be associated with ES. After infection is ruled out, ES should be considered in the differential diagnosis when evaluating AKI in this population.

Renal histology in patients with elevated serum creatinine and concurrent normal urinalysis.

INTRODUCTION: Diagnosis of kidney disease is currently and primarily based on the measurement of serum creatinine, blood urea nitrogen, and urine output, and most kidney diseases with elevated serum creatinine accompany abnormal findings of urinalysis with microscopy, such as proteinuria or hematuria. The purpose of the current study was to determine the histologic diagnosis of patients with elevated serum creatinine and a concurrent normal urinalysis without underlying disease. METHODS: The medical records of patients who had undergone kidney biopsies between January 1, 2003 and March 1, 2008 in three medical centers were retrospectively reviewed. The patients with an elevated serum creatinine level and a normal urinalysis were enrolled. The exclusion criteria were as follows: diabetes mellitus; hypertension; chronic liver disease; malignancies; autoimmune diseases; dependence on medications; hypokalemic nephropathy; age < 18 years. Age, duration of follow-up, post-biopsy management, and the change in levels of BUN and serum creatinine from pre-biopsy to the last visit were analyzed. RESULTS: All 15 patients were included. The most frequent single diagnosis was acute interstitial interstitial nephritis, followed by hypertensive nephrosclerosis. Chronic interstitial nephritis, mesangial proliferative glomerulonephritis, acute tubular necrosis, secondary amyoloidosis, focal segmental glomerulosclerosis, and minor glomerular change were listed. The young group (< 40 years of age) included more patients with acute interstitial nephritis, and the old group (≥ 40 years of age) included more patients with hypertensive nephrosclerosis. CONCLUSION: Based on a correct histological diagnosis, all of the patients, except one, were properly managed and had preserved kidney function until the last visit.

Role of glycosaminoglycan sulfation in the formation of immunoglobulin light chain amyloid oligomers and fibrils.

Primary amyloidosis (AL) results from overproduction of unstable monoclonal immunoglobulin light chains (LCs) and the deposition of insoluble fibrils in tissues, leading to fatal organ disease. Glycosaminoglycans (GAGs) are associated with AL fibrils and have been successfully targeted in the treatment of other forms of amyloidosis. We investigated the role of GAGs in LC fibrillogenesis. Ex vivo tissue amyloid fibrils were extracted and examined for structure and associated GAGs. The GAGs were detected along the length of the fibril strand, and the periodicity of heparan sulfate (HS) along the LC fibrils generated in vitro was similar to that of the ex vivo fibrils. To examine the role of sulfated GAGs on AL oligomer and fibril formation in vitro, a κ1 LC purified from urine of a patient with AL amyloidosis was incubated in the presence or absence of GAGs. The fibrils generated in vitro at physiologic concentration, temperature, and pH shared morphologic characteristics with the ex vivo κ1 amyloid fibrils. The presence of HS and over-O-sulfated-heparin enhanced the formation of oligomers and fibrils with HS promoting the most rapid transition. In contrast, GAGs did not enhance fibril formation of a non-amyloidogenic κ1 LC purified from urine of a patient with multiple myeloma. The data indicate that the characteristics of the full-length κ1 amyloidogenic LC, containing post-translational modifications, possess key elements that influence interactions of the LC with HS. These findings highlight the importance of the variable and constant LC regions in GAG interaction and suggest potential therapeutic targets for treatment.

Analysis of clinical and pathological characteristics of 28 cases with renal amyloidosis.

BACKGROUND: This study was planned to summarize the clinical and pathological features of renal amyloidosis in order to improve its early and accurate diagnosis. METHODS: The clinical and pathological data were analyzed from 28 patients with renal amyloidosis in the Second Xiangya Hospital from January 2005 to September 2010. RESULTS: Twenty seven out of the 28 (96.4%) cases were over 40 years old and presented with nephrotic syndrome. The initial diagnosis of 23 patients (82.1%) was not renal amyloidosis at their first visit to the local hospital. The pathophysiological finding included diffused deposition of amorphic and eosinophilic amyloid substance in glomerular mesangial, capillary membrane loop, interstitial, vascular, and tubular wall. 26 cases were attributed to the AL type and 2 cases to AA type. 25 patients (89.3%) were found to have monoclonal light chain in serum or urine by protein electrophoresis. CONCLUSIONS: Renal amyloidosis is frequently neglected by local physicians in China. Renal amyloidosis should be highly suspected if the middle-aged nephrotic patient was accompanied by weight loss, organ enlargement, and monoclonal light chains in serum or urine. Renal biopsy, especially with examination under the electron microscopy, is the key to the early diagnosis of renal amyloidosis. Potassium permanganate staining and immunofluorescence examination could help to distinguish primary from secondary amyloidosis.

Cervical cancer of the uterus complicated by renal AA amyloidosis.

Cervical cancer of the uterus rarely develops systemic secondary amyloidosis. We present the case of a 66-year-old female patient who manifested systemic amyloid A (AA) amyloidosis in the kidney, digestive tract, and cervix of the uterus, secondary to cervical cancer. She exhibited nephrotic syndrome, intractable diarrhea, and mild fever 3 months after she underwent an extended hysterectomy with postoperative cisplatin-based chemotherapy and whole pelvic irradiation. Further examinations revealed AA amyloidosis of the kidney and colon and cytomegalovirus infection in the colon. AA amyloid deposition was positive in the resected tissues of uterine cancer. The patient was diagnosed with systemic AA amyloidosis consecutive to cervical cancer. Despite a decrease in urinary protein after antiviral therapy, it increased 14 months later with neither apparent symptoms nor an increase in tumor marker. A second renal biopsy revealed AA amyloidosis of the kidney. Subsequent investigations revealed the recurrence of cervical cancer in the lung, liver, and lymph nodes. This case report indicated that AA amyloidosis would complicate cervical cancer and recur even after resection of neoplasm owing to other stimulation. Moreover, urine protein could be a marker for cancer relapse in known cases of cancer-derived AA amyloidosis.

Identification of amyloidogenic light chains requires the combination of serum-free light chain assay with immunofixation of serum and urine.

BACKGROUND: The diagnosis of systemic immunoglobulin light-chain (AL) amyloidosis requires demonstration of amyloid deposits in a tissue biopsy and amyloidogenic monoclonal light chains. The optimal strategy to identify the amyloidogenic clone has not been established. We prospectively assessed the diagnostic sensitivity of the serum free light chain (FLC) kappa/lambda ratio, a commercial serum and urine agarose gel electrophoresis immunofixation (IFE), and the high-resolution agarose gel electrophoresis immunofixation (HR-IFE) developed at our referral center in patients with AL amyloidosis, in whom the amyloidogenic light chain was unequivocally identified in the amyloid deposits. METHODS: The amyloidogenic light chain was identified in 121 consecutive patients with AL amyloidosis by immunoelectron microscopy analysis of abdominal fat aspirates and/or organ biopsies. We characterized the monoclonal light chain by using IFE and HR-IFE in serum and urine and the FLC kappa/lambda ratio in serum. We then compared the diagnostic sensitivities of the 3 assays. RESULTS: The HR-IFE of serum and urine identified the amyloidogenic light chain in all 115 patients with a monoclonal gammopathy. Six patients with a biclonal gammopathy were omitted from the statistical analysis. The diagnostic sensitivity of commercial serum and urine IFE was greater than that of the FLC kappa/lambda ratio (96% vs 76%). The combination of serum IFE and the FLC assay detected the amyloidogenic light chain in 96% of patients. The combination of IFE of both serum and urine with the FLC kappa/lambda ratio had a 100% sensitivity. CONCLUSIONS: The identification of amyloidogenic light chains cannot rely on a single test and requires the combination of a commercially available FLC assay with immunofixation of both serum and urine.

Is the urinary protein excretion pattern compatible with renal morphological findings in renal amyloidosis?

The aims of this study are to compare urinary protein excretion pattern with renal morphological findings and to find out whether urinary protein excretion pattern is a prognostic indicator of renal amyloidosis. Fifteen children with renal amyloidosis secondary to familial Mediterranean fever were included in the study. The patients were classified into three groups according to the degree of tubulointerstitial injury in renal biopsy (group 1, <25%; group 2, 25-50%; and group 3, >50%). In all patients, urinary protein electrophoresis were performed. Levels of urinary beta(2)-microglobulin, retinol binding protein, and beta.N-acetyl-D glucosaminidase were measured as markers for tubular injury, and urinary excretions of protein and albumin and plasma albumin levels were measured as markers of glomerular injury. While urinary excretions of protein and albumin and plasma albumin levels were not different between groups, higher urinary beta(2-)microglobulin and retinol binding protein values and lower creatinine clearance values were found in group 3 than in groups 1 and 2 (p < 0.05). We concluded that analysis of urinary protein excretion pattern is a non-invasive and reliable method to detect the degree of tubulointerstitial injury as the most important prognostic factor in renal amyloidosis and may be used to determine the changes during the follow-up period of the patients.

Evaluation of the serum-free light chain test in untreated patients with AL amyloidosis.

We evaluated the Serum Free Light Chain (FLC) test in a series of 133 untreated patients with systemic AL amyloidosis. The FLC test detected the monoclonal gammopathy in 87% compared with 92% for immunofixation of serum and urine in combination. However, both tests proved complementary. The FLC test was also a valuable tool in patients with advanced renal failure in spite of uninvolved light chain retention. Higher FLC levels were associated with higher bone marrow plasmocytosis, poorer Karnofsky index and heart involvement, and therefore reflected disease severity.

Involvement of beta 2-microglobulin modified with advanced glycation end products in the pathogenesis of hemodialysis-associated amyloidosis. Induction of human monocyte chemotaxis and macrophage secretion of tumor necrosis factor-alpha and interleukin-1.

beta 2-Microglobulin (beta 2M) is a major constituent of amyloid fibrils in hemodialysis-associated amyloidosis (HAA), a complication of long-term hemodialysis. However, the pathological role of beta 2M in HAA remains to be determined. Recently, we demonstrated that beta 2M in the amyloid deposits of HAA is modified with advanced glycation end products (AGEs) of the Maillard reaction. Since AGEs have been implicated in tissue damage associated with diabetic complications and aging, we investigated the possible involvement of AGE-modified beta 2M (AGE-beta 2M) in the pathogenesis of HAA. AGE- and normal-beta 2M were purified from urine of long-term hemodialysis patients. AGE-beta 2M enhanced directed migration (chemotaxis) and random cell migration (chemokinesis) of human monocytes in a dose-dependent manner. However, normal-beta 2M did not enhance any migratory activity. AGE-beta 2M, but not normal-beta 2M, increased the secretion of TNF-alpha and IL-1 beta from macrophages. Similar effects were also induced by in vitro prepared AGE-beta 2M (normal-beta 2M incubated with glucose in vitro for 30 d). When TNF-alpha or IL-1 beta was added to cultured human synovial cells in an amount equivalent to that secreted from macrophages in the presence of AGE-beta 2M, a significant increase in the synthesis of collagenase and morphological changes in cell shape were observed. These findings suggested that AGE-beta 2M, a major component in amyloid deposits, participates in the pathogenesis of HAA as foci where monocyte/macrophage accumulate and initiate an inflammatory response that leads to bone/joint destruction.

Analytical performance of serum free light-chain assay during monitoring of patients with monoclonal light-chain diseases.

BACKGROUND: Measurement of serum free light chains (FLC) is useful for the diagnosis and monitoring of monoclonal light-chain diseases. It has been suggested that there will be widespread replacement of urine Bence Jones protein measurement by serum FLC assay. We report on our experience with the assay during monitoring of light-chain myeloma (LCMM) and AL amyloidosis (AL). METHODS: Serum FLC immunoassay, serum and/or urine protein electrophoresis and immunofixation were performed on serial samples during monitoring of LCMM. Recovery and immunoreactivity of FLC were tested by sample dilution. Assay precision was determined by repeat assay of samples over several reagent lots. RESULTS: In one of 23 patients with LCMM there was non-reaction of a monoclonal kappa FLC with some reagent lots and the assay did not indicate disease relapse. Samples showed non-linear, non-parallel immunoreactivity on dilution. Several tested monoclonal FLC gave lower values at the assay starting dilution compared with higher sample dilution and non-parallel dose-response curves. The median between-reagent lot variation for FLC measurement was 19-20% CV. CONCLUSIONS: Laboratory staff and clinicians need to be aware of the potential for non-reactivity of individual monoclonal FLC, and the effects of dilution and precision on FLC values and their interpretation.

Urinary glycosaminoglycan levels as a marker of renal amyloidosis in patients with familial Mediterranean fever.

INTRODUCTION AND AIM: Familial Mediterranean Fever (FMF) is an autosomal recessive disease with a defect in the pyrine gene and is manifested with short attacks of inflammatory serositis, fever, and erysipelas-like skin lesions. Secondary amyloidosis is the most serious complication of the disease, in which extracellular deposits of amyloid (an amorphous and eosinophilic protein) are seen in tissues. Glycosaminoglycans are mucopolysaccharide molecules that take place in amyloid deposits with fibrillar links to amyloid. They form glycoproteins by linking to proteins, and their free forms are excreted in the urine in the form of polysaccharides. The aims of this study were to evaluate if the urinary levels of glycosaminoglycans have a predictive value in the diagnosis of amyloidosis secondary to FMF and if these levels are affected by treatment with colchicine. MATERIALS AND METHODS: The study included 55 volunteer patients (age range: 18-36 years) with FMF (15 with amyloidosis) of the same socio-economic circumstances without other concomitant inflammatory, malignant, or chronic diseases, along with 20 healthy subjects as control. Urinary glycosaminoglycan levels were determined twice, once when the patients were on medication and once after they have stopped treatment for two weeks. RESULTS: Initial mean urinary GAG levels were significantly lower in amyloidosis patients. Mean urinary GAG levels determined two weeks after the cessation of colchicine was also significantly lower than controls in both amyloidosis and non-amyloidosis FMF patients. Likewise, in patients with a disease duration longer than ten years, urinary GAG levels were also lower than those with a disease duration of less than three years. CONCLUSION: Urinary GAG level can have a predictive value for amyloidosis in patients with FMF, and it can also be used as a non-invasive marker for screening the effects of colchicine on fibrillogenesis as well as for the follow-up of the patients.

Renal Amyloidosis Associated With Kartagener Syndrome in a Dog.

A 4-year-old cocker spaniel, male, of 12kg body weight was presented because of the onset of polyuria or polydipsia. From the first months of its life, the dog had exhibited constant serous to mucopurulent nasal discharge, productive cough, sneezing, reverse sneezing, otitis, and recurrent episodes of fever. The respiratory signs had been treated several times with antibiotics, without ever achieving a complete resolution. Clinical examination revealed normal rectal temperature (38.3°C), increased respiratory rate (40breaths/min), a copious mucous nasal discharge and right deviation of the heart apex beat (ictus cordis). Increased respiratory sounds with moist rales and crackles were found on chest auscultation. An increase in serum creatinine, urea and phosphorus, hypoalbuminemia and proteinuria were found. Lateral and ventrodorsal radiographs of the thorax and of the abdomen showed the transposition of the heart, with the cardiac apex pointing toward the right (dextrocardia), bronchointerstitial lung pattern, areas of consolidation, lesions consistent with bronchiectasis caves and a mirror-image of abdominal organs, confirming the diagnosis of complete situs inversus (CSI). Respiratory signs, combined with CSI, suggested the diagnosis of Kartagener syndrome (KS). Abdominal ultrasound showed an increase in the echogenicity of the renal parenchyma, a loss of definition of the corticomedullary line, slight bilateral pyelectasis, and decreased cortical perfusion. The dog died 2 months later because of a further worsening of the clinical condition. Necroscopy demonstrated the existence of CSI, rhinosinusitis, bronchitis, and bronchiectasis, so confirming the diagnosis of KS, and renal amyloidosis. This is the first case reported in veterinary medicine of the presence of renal amyloidosis together with KS in a dog.