Beta 2-microglobulin amyloidosis in a patient treated exclusively by continuous ambulatory peritoneal dialysis

Destructive Spondyloarthropathy in a Patient on Continuous Ambulatory Peritoneal Dialysis for 13 Years

Since 1984 there have been reports of a destructive spondyloarthropathy occurring in patients on long-term hemodialysis. The primary abnormality appears to be an accumulation of β2-microglobulin, which is not adequately removed by dialysis, and forms amyloid deposits in articular and periarticular tissues. We report a case of this disease in a patient treated only by peritoneal dialysis. While this form of treatment may delay the development of arthropathy, as compared to hemodialysis, it does not prevent it. An increasing incidence of this disorder may be expected, since increasing numbers of patients have been on long-term peritoneal dialysis.

beta 2 M-amyloidosis and gastrointestinal bleeding after renal transplantation

Dialysis-related amyloidosis is a disorder that commonly develops in long-term dialysis with an incidence that is linked to the duration of hemodialysis. The amyloid deposits are composed of the amyloid precursor beta 2 microglobulin, mainly affecting the osteoarticular system, but also involving extra-osteoarticular tissues. We present a patient with repeated rectal bleeding caused by a circumferential atone ulcer in the immediate posttransplantation period due to the use of a rectal canula after 27 years of treatment with hemodialysis. Histopathological examination of the rectal ulcer biopsy specimens revealed positive Congo red stain and additional immunohistochemical investigation showed the presence of beta 2-microglobulin in a blood vessel wall of the rectum. Although dialysis related amyloidosis may be partially prevented, it is important to remain alert for dialysis related amyloidosis complications after renal transplantation in patients with a longstanding history of dialysis.

Dialysis-related amyloidosis: history and clinical manifestations

Dialysis-related amyloidosis (DRA) or beta(2)-microglobulin amyloidosis (A beta(2)M) is a unique type of amyloidosis that has been described in individuals with both long-standing chronic renal disease and end-stage renal disease (ESRD). It has been associated with serious complications that significantly add to the morbidity of long-term dialysis patients. The deposition of beta(2)M in amyloid fibrils in various joint and osteoarticular surfaces leads to the clinical complaints and findings typical of this disorder. However, a visceral form with systemic organ involvement has also been described. Despite advances in the understanding of this disorder and in the delivery of dialysis, the ability to alter the incidence of DRA and its course remains uncertain.

Effect of hemodialysis membranes on beta 2-microglobulin amyloidosis

Early after the identification of beta(2)-microglobulin amyloidosis (A beta(2)M) as the cause of carpal tunnel syndrome, it was thought that hemodialysis was a major cause in the development of the disease. It was subsequently shown that hemodialysis was not necessary for the development of dialysis-related amyloidosis; however, it was believed that the different dialysis membranes did modulate the progression of the disease. Current data demonstrate that hemodialysis fails to prevent or reverse the disease, but there is substantial evidence that high-flux, high-efficiency dialyzers slow its progression. Many factors related to hemodialysis have been evaluated in relation to A beta(2)M, including the effect of the bioincompatibility of the membrane, the capacity of the different membranes to remove beta(2)M, and the effect of reuse on beta(2)M levels. Moreover, there have been intensive efforts to evaluate, explore, and improve the different mechanisms in beta(2)M removal, with adsorption as a promising prospect. With the available evidence, it seems that the removal of beta(2)M by the membrane plays the most important role in modulating the disease outcome and rate of progression, although a large, long-term, multicentered and randomized study is still lacking to prove this relationship. However, it is possible that with the continuing advances in optimizing the beta(2)M removal efficiency of the different membranes, the frequency and severity of the disease can be substantially decreased.

Rat extracorporeal circulation model for evaluation of systemic immunotoxicity

We have applied a rat extracorporeal circulation (EC) model as an evaluation system for the immunotoxicity of medical devices in contact with the blood stream. Combining popular hemodialysis (HD) membranes [a non-biocompatible membrane, Cupurophane (CUP), and more biocompatible membranes, Cu-ammonium rayon (CAR) and polyacrylonitrile (PAN)] with rat EC, we evaluated the elicitation of acute and delayed immunological responses, as well as the effect of repeated EC. Acute effect markers such as the production of tumor necrosis factor (TNF)-alpha and complement activity during EC, and delayed effect markers such as beta2-microglobulin (beta2-M), IgG, and complement 3 levels, were monitored. Acute markers after EC passage showed responses similar to those previously reported in patients with long-term hemodialysis such as TNF-alpha production and increased complement activity. Although beta2-M and IgG levels increased to 3- to 5-fold of the initial concentration within 4 weeks after rat EC, the trend of IgG increase was inversely correlated with membrane biocompatibility (CUP > CAR = PAN), but this did not occur for elevations in beta2-M (PAN > CAR > CUP). These data suggest that this EC model can reproduce similar immunological responses as seen in HD patients, and can be employed to evaluate medical devices and materials for their delayed, systemic, and repeated exposure effects with respect to immunotoxicity.

Fatal cervical spondyloarthropathy in a hemodialysis patient with systemic deposition of beta2-microglobulin amyloid

Destructive spondyloarthropathy is a serious complication in patients with end-stage renal disease. We report a case of fatal cervical spondyloarthropathy in a patient on hemodialysis who presented with severe pain in the cervical area. Magnetic resonance imaging (MRI) of the cervical spine showed a soft tissue mass at the cervico-occipital hinge with spinal cord compression and destructive lesions of the cervical vertebrae. The patient became quadriplegic during the MRI procedure and died a few days later. Postmortem examination showed deposition of beta2-microglobulin in the cervico-occipital hinge. A unique feature of this case was the documented presence of systemic beta2-microglobulin amyloid deposits involving the spleen that to our knowledge has not been reported previously. Clinical suspicion and early detection of lesions caused by dialysis-related amyloidosis (DRA) may help to prevent significant morbidity and mortality in long-term dialysis patients.

Prevalence of histological beta2-microglobulin amyloidosis in CAPD patients compared with hemodialysis patients

BACKGROUND

The prevalence of beta2-microglobulin amyloidosis (Abeta2m) in patients on continuous ambulatory peritoneal dialysis (CAPD) is unknown.

METHODS

We prospectively obtained a median of 2 (range 1 to 4) joint samples from 26 CAPD patients aged 44 to 93 (median 73) years at post-mortem evaluation after 4.5 to 126 (median 27) months solely on CAPD (N = 19) or primarily on CAPD (that is, < or = 10% and < or = 1 year of renal replacement therapy time on other modalities; N = 7). The diagnosis of Abeta2m rested on Congo red staining (typical birefringence) and positive immunostaining of amyloid deposits by a monoclonal anti-beta2m antibody.

RESULTS

Abeta2m was diagnosed in 8 of 26 patients (31%). Prevalence ranged from 20% (2 of 10 patients) within < or = 24 months CAPD to 30% (3 of 10 patients) after 24 to 48 months and 50% (3 of 6 patients) after 49 to 126 months (P = 0.11). The prevalence of Abeta2m was similar in patients without or with one or more peritonitis episodes. No significant difference in prevalence (P = 0.118) was found between CAPD patients (8+/26; 31%) and hemodialysis patients (13+/26; 50%) carefully matched for time on dialysis and age at the onset of dialysis.

CONCLUSIONS

The prevalence of histological Abeta2m reaches 31% after a median duration of 27 months of CAPD. This prevalence is not significantly different from that observed in a group of HD patients matched for age and dialysis duration.

Histological prevalence of beta 2-microglobulin amyloidosis in hemodialysis: a prospective post-mortem study

The histological prevalence of beta-2 microglobulin amyloidosis (A beta 2m) was evaluated in a prospective study of joint samples obtained at autopsy in 54 patients on hemodialysis (HD) for 2 to 163 (median 47) months, aged 20 to 80 (median 63) years at HD onset. Carpal tunnel syndrome surgery or radiological signs of A beta 2m were present in 2 and 4% of them, respectively. A control group of 34 patients without end-stage renal disease, autopsied during the same period was used as a reference. The 153 sampled joints (1 to 8, median 2 per patient) were sternoclavicular joints (N = 77), shoulders (N = 35), knees (N = 28), others (N = 13). A beta 2m was diagnosed (positive Congo red with typical birefringence and positive immunostaining of deposits for beta 2m) in 26 of 54 (48%) patients. Prevalence reached respectively 21%, 33%, 50%, 90% and 100% within two years, after 2 to 4 years, 4 to 7 years, 7 to 13 years and more than 13 years HD. The calculated sensitivity of the various joints for A beta 2m detection is significantly higher (P < 0.03) for sternoclavicular joints (97%) and knees (91%) than for shoulders (57%). Multivariate stepwise logistic regression with discriminant analysis identified both HD duration (P = 0.0008) and age at HD onset (P = 0.0093) but not diabetic nephropathy (P = 0.23) or gender (P = 0.25) as independent risk factors for A beta 2m. The probability of joint A beta 2m was quantitated as a function of age and HD duration. In conclusion, A beta 2m may be observed in the large joints early after HD onset. Overall prevalence reaches 48% of the patients on HD for a median of 47 months. It is much higher than that reported on the basis of clinical or radiological evidence. The sternoclavicular and knee joints are more frequently (P < 0.03) involved than the shoulder. The easily accessible sternoclavicular joint therefore appears to be the best site for the early detection of A beta 2m. Both HD duration and age at HD onset, but not diabetic nephropathy, are independent risk factors for A beta 2m.

Histological beta-2-microglobulin amyloidosis 10 years after a successful renal transplantation

In a patient successfully transplanted 10 years earlier, we confirm that wrist and shoulder bone cysts, present at the time of transplantation, remain unchanged in size and number and demonstrate, for the first time, that they still contain beta-2-microglobulin (beta2m) amyloid. Regression of beta2m amyloid deposits in bone cysts disappears, if at all, very slowly.

Treatment of amyloidosis

Amyloidosis is the extracellular deposition of normally soluble autologous protein in a characteristic abnormal fibrillar form. Systemic amyloidosis and some local forms are progressive, cause major morbidity, and are often fatal. No treatment specifically causes the resolution of amyloid deposits, but therapy that reduces the supply of amyloid fibril precursor proteins can improve survival and preserve organ function. Major regression of amyloid occurs in at least a proportion of such cases, suggesting that the clinical improvement reflects mobilization of amyloid. The clearest evidence for regression of amyloid has been obtained in juvenile rheumatoid arthritis patients with AA amyloidosis treated with chlorambucil. This drug suppresses the acute phase production of serum amyloid A protein, the precursor of AA amyloid fibrils, and is associated with remission of proteinuria and greatly improved survival. In many such patients, scintigraphy with serum amyloid P component shows major regression of amyloid over 12 to 36 months and frequently reveals a discrepancy between the local amyloid load and organ dysfunction. Measurement of target organ function is therefore not an adequate method for monitoring treatment aimed at promoting the resolution of amyloid. In monoclonal immunoglobulin light chain (AL) amyloidosis the aim of treatment is to suppress the underlying B-cell clone and, therefore, production of the amyloid fibril precursor protein. This can be difficult to achieve or sustain and, since the prognosis is so poor, many patients die before benefits of therapy are realized. A recent development has been the introduction of liver transplantation as treatment for familial amyloid polyneuropathy caused by transthyretin gene mutations. This leads to the disappearance of variant transthyretin from the plasma and halts progression of the neurologic disease. Features of autonomic neuropathy frequently ameliorate, and improvement in peripheral motor nerve function has been recently reported. Serum amyloid P component scans show regression of associated visceral amyloidosis. This surgical form of gene therapy holds much promise for patients with familial amyloid polyneuropathy and has been widely adopted. The only other form of amyloidosis in which the supply of the fibril precursor protein can be sharply reduced is beta 2M amyloidosis in long-term hemodialysis patients. Renal transplantation lowers the plasma concentration of beta 2M to normal levels and is associated with rapid improvement of the osteoarticular symptoms. Preliminary observations suggest that the beta 2M amyloid deposits also can regress in some patients.(ABSTRACT TRUNCATED AT 400 WORDS)

Amyloidosis

Amyloidosis is the generic term for a heterogeneous group of disorders characterised by the common finding of amyloid deposition. The various acquired and hereditary syndromes are classified according to the identity of the respective amyloid fibril sub-unit protein. Systemic amyloidosis and some local forms are progressive diseases that are frequently fatal. The diagnosis of systemic amyloidosis is only occasionally suspected on clinical grounds alone, and is more often considered when an associated disorder such as a chronic inflammatory disease or monoclonal gammopathy is present. No blood test is diagnostic of amyloidosis but routine haematological and biochemical investigations have important roles in defining the underlying metabolic disturbance and evaluating function of affected organs. The diagnosis can only be confirmed by demonstrating the presence of tissue amyloid deposits. Traditionally this required histology but the recent introduction of labelled serum amyloid P component scintigraphy is a specific alternative that provides a quantitative macroscopic whole body survey of amyloid deposits. No treatment specifically causes the resolution of amyloid but therapy which reduces the supply of amyloid fibril precursor proteins can improve survival and preserve organ function. Major regression of amyloid occurs in at least a proportion of such cases suggesting that clinical improvement reflects mobilisation of amyloid.

Role of bioincompatibility in dialysis morbidity and mortality

This review examines the mechanisms by which bioincompatibility in dialysis systems may have an effect on morbidity and mortality in the dialysis population. Direct toxic effects of membrane materials and various chemical substances have been well demonstrated in the chronic dialysis population. Activation of the complement cascade and stimulation of cytokine production may have autocrine effects on leukocyte function with sequelae such as enhanced rates of infection and the development of B2-microglobulin amyloidosis. The variable effect of different membrane materials on each of these effector systems is examined. Bioincompatibility may effect the incidence of infection, malignancy, cardiopulmonary disease, and malnutrition as well as induce novel disease processes. All these confounding variables must be considered when evaluating the effect of dialysis on mortality and morbidity.

beta 2-Microglobulin and the kidney: an overview

beta 2 microglobulin is a potentially amyloidogenic low molecular weight protein. Increased serum levels are seen in renal diseases that decrease glomerular filtration and/or tubular reabsorption, dialysis patients, chronic inflammatory diseases, and certain malignancies. Various aspects of beta 2 microglobulin metabolism and its accumulation in the kidney are addressed.

Musculoskeletal manifestations in beta 2-microglobulin amyloidosis. Case discussion

The cases presented illustrate some of the typical (case 1) and less common (case 2) clinical features of beta 2m amyloidosis. The accumulation of beta 2m amyloid in tissues is a potentially severe complication of dialysis-treated chronic renal failure. Beta 2m amyloidosis has been shown to have distinct clinical, radiologic, and pathologic features. The pathogenesis of this condition is not yet clearly understood, and recommendations for the clinical management of these patients at present are limited to recognition of the disease and symptomatic treatment. Further insights into the biology of this disease should lead to new strategies for prevention and treatment.

Musculoskeletal complications after renal transplantation: pathogenesis and treatment

Renal transplantation is associated with several abnormalities of function and structure of the musculoskeletal system. Some of these skeletal problems result from incomplete resolution of abnormalities of bone and mineral metabolism present at the time of transplantation. In this regard, persistent hyperparathyroidism, diabetes mellitus type 1, and accumulation of beta 2-microglobulin may lead to residual skeletal effects despite excellent function of the allograft. Persistent hyperparathyroidism may accelerate bone loss and increase the risk for osteonecrosis, as well as cause hypercalcemia and hypophosphatemia; some patients with severe hyperparathyroidism require parathyroid surgery. Osteonecrosis is the most debilitating skeletal complication after transplantation and frequently requires surgical therapy. Although osteomalacia associated with aluminum overload generally resolves after transplantation, bone complications due to dialysis amyloidosis and diabetes mellitus type 1 often fail to improve. Alternatively, skeletal abnormalities can be acquired after transplantation. Most of the new derangements of bone and mineral metabolism are due to the immunosuppressive medications. Toxic effects of glucocorticoids on bone contribute to the pathogenesis of osteonecrosis, increase the risk for fractures by decreasing cancellous bone mass and synthesis of bone matrix, and dampen the linear growth response in pediatric recipients. Whether cyclosporine independently causes appreciable toxic effects on bone metabolism is not yet clear, but use of this drug increases the prevalence of gout and dental problems. Osteonecrosis, osteopenia, and short stature remain important skeletal complications in recipients of renal allografts. Therapeutic efforts should be directed toward alleviating pretransplant bone disease and attenuating bone loss after transplantation.

Serum amyloid P component in chronic renal failure and dialysis

A normal reference interval for serum amyloid P component (SAP) concentration in the serum was established in 500 healthy adult individuals (274 women, 226 men), by electroimmunoassay calibrated with standards of highly purified, isolated SAP. The mass of SAP in these was determined from the extinction coefficient of SAP at 280 nm measured here precisely for the first time by spectrophotometry and cryogenic drying. The mean (SD, range) SAP concentration was significantly lower in women: 24 mg/l (8, 8-55), compared to 32 mg/l (7, 12-50) in men (P less than 0.001). In renal insufficiency patients, 38 with chronic renal failure, 79 on hemodialysis and 66 on continuous ambulatory peritoneal dialysis, the mean values for SAP concentration were all significantly higher than normal (range of means, 39-59 mg/l in men and 35-42 mg/l in women), but did not correlate with serum creatinine, duration of dialysis or the presence of an acute phase response. The metabolism of SAP is thus altered in renal failure and is not normalized by dialysis, but it is not clear whether this is relevant to the pathogenesis of dialysis related arthropathy and amyloidosis.