Beta2-microglobulin amyloidosis in hemodialysis and peritoneal dialysis patients

Peritoneal Dialysis for Potential Kidney Transplant Recipients: Pride or Prejudice?

Kidney transplantation (KT) is recognized as the gold-standard of treatment for patients with end-stage renal disease. Additionally, it has been demonstrated that receiving a pre-emptive KT ensures the best recipient and graft survivals. However, due to an overwhelming discrepancy between the organs available and the patients on the transplant waiting list, the vast majority of transplant candidates require prolonged periods of dialysis before being transplanted. For many years, peritoneal dialysis (PD) and hemodialysis (HD) have been considered competitive renal replacement therapies (RRT). This dualistic vision has recently been questioned by evidence suggesting that an individualized and flexible approach may be more appropriate. In fact, tailored and cleverly planned changes between different RRT modalities, according to the patient's needs and characteristics, are often needed in order to achieve the best results. While home HD is still under scrutiny in this particular setting, current data seems to favor the use of PD over in-center HD in patients awaiting a KT. In this specific population, the demonstrated advantages of PD are superior quality of life, longer preservation of residual renal function, lower incidence of delayed graft function, better recipient survival, and reduced cost.

Comparison of shoulder Magnetic Resonance Imaging findings between patients with stage 4 chronic kidney disease and hemodialysis patients with healthy controls

BACKGROUND

Shoulder involvement is frequently observed in chronic renal disease (CRD) and hemodialysis patients.

OBJECTIVE

Our aim is to compare shoulder Magnetic Resonance Imaging (MRI) findings of stage 4 CRD patients naive to dialysis, hemodialysis patients and healthy controls.

METHODS

Twenty hemodialysis patients with shoulder pain (Group 1), 30 hemodialysis patients without shoulder pain (Group 2), 20 patients with stage 4 CRD (Group 3) and 30 healthy controls (Group 4) were enrolled. Urea, creatinine and β2 microglobulin were measured. Thickness, homogeneity and integrity of rotator cuff and presence of effusion were examined by MRI.

RESULTS

Supraspinatus tendon was thicker in Group 1 compared to other groups, whereas infraspinatus tendon was thicker in Group 1 compared to Groups 2 and 4. Although all tendons thickness was higher in Group 3 than Group 4, there was no significant difference. Most effusion areas were present in Group 1, followed by Groups 2 and 3. There was a significant correlation between glomerular filtration rate and thickness of supraspinatus, infraspinatus tendons and between β2 microglobulin and thickness of infraspinatus, subscapularis tendons and total number of areas with effusion.

CONCLUSIONS

Increased shoulder tendon thickness and effusion were detected in symptomatic dialysis patients, while greater effusion areas were detected in asymptomatic dialysis patients and in stage 4 CRD patients who do not require dialysis compared to healthy controls.

Tendon thickening in dialysis-related joint arthritis is due to amyloid deposits at the surface of the tendon

OBJECTIVES

Beta-2-microglobulin (β2M) dialysis-related amyloidosis (DRA), a disabiliting joint disease, has been initially reported in patients under long-term dialysis. The incidence and prevalence has significantly decreased with the improvement in dialysis techniques. Here, we attempted to clarify the clinical and MRI features to improve the diagnosis.

METHODS

We retrospectively reviewed the files of 19 patients under dialysis treatment referred for suspicion of β2M DRA. The diagnosis was based on MRI criteria (low signal intensity on both T1- and T2-weighted MR sequences). MRI analysis included a scoring of the several joint lesions. Scores were quantified according to a severity scale (0 to 3).

RESULTS

Patients had a mean age of 66.0 ± 10.5 years and mean dialysis duration of 23.7 ± 10.5 years. DRA affected mainly large joints (shoulder in 73.7%, hip in 47.3%) and spine (36.8%). MRI images for 8 shoulders, 8 hips, and 3 spines were analysed. Amyloid synovitis was present in all cases, with high mean scores in the three sites. In all joints, the most common lesions were tendon thickening (68.4%) and bone erosions (68.4%). The mean tendon thickening score was high, particularly at the shoulders and also at the spine. Bone erosions were most frequent in the shoulder and pelvis.

CONCLUSION

In patients under long-term dialysis, β2M DRA involves large joints but also the spine. Special awareness should be drawn by the thickening of the tendon. MRI is required to characterize the pattern of the lesions and to achieve the diagnosis.

Painful and painless shoulder Magnetic Resonance Imaging comparisons in hemodialysis patients and correlation with clinical findings

BACKGROUND

Shoulder pain is frequently observed in haemodialysis patients.

OBJECTIVE

To compare haemodialysis patients with or without shoulder pain in terms of shoulder motion ranges, β2 microglobulin levels and magnetic resonance imaging findings.

METHODS

Forty-three patients undergoing dialysis were enrolled, of which 23 patients had explicit shoulder pain at night, which appeared during dialysis. Range of joint motion was evaluated. β 2 microglobulin value was recorded. MRI was used to evaluate rotator cuff tendons for thickness, homogeneity, integrity and presence of effusion.

RESULTS

Ranges of motion were significantly lower in the painful shoulder group. Supraspinatus tendon thickness and the number of areas with effusion were higher in the painful group. There was a positive correlation between the β 2 microglobulin level and supraspinatus (r:0.352 p< 0.05) and subscapular (r:0.454 p< 0.05) tendon thicknesses. While effusion areas and pain (r:0.351 p< 0.05) showed positive correlation, there was a negative correlation between pain and shoulder motion ranges.

CONCLUSIONS

Shoulder pain in dialysis patients can be related with tendon thickness and effusion. While the β 2 microglobulin level affects tendon thickness, it has no relation to pain and movement constraint.

Dialysis-related amyloidosis: challenges and solutions

Amyloidosis refers to the extracellular tissue deposition of fibrils composed of low-molecular-weight subunits of a variety of proteins. These deposits may result in a wide range of clinical manifestations depending upon their type, location, and the amount of deposition. Dialysis-related amyloidosis is a serious complication of long-term dialysis therapy and is characterized by the deposition of amyloid fibrils, principally composed of β2 microglobulins (β2M), in the osteoarticular structures and viscera. Most of the β2M is eliminated through glomerular filtration and subsequent reabsorption and catabolism by the proximal tubules. As a consequence, the serum levels of β2M are inversely related to the glomerular filtration rate; therefore, in end-stage renal disease patients, β2M levels increase up to 60-fold. Serum levels of β2M are also elevated in several pathological conditions such as chronic inflammation, liver disease, and above all, in renal dysfunction. Retention of amyloidogenic protein has been attributed to several factors including type of dialysis membrane, prolonged uremic state and/or decreased diuresis, advanced glycation end products, elevated levels of cytokines and dialysate. Dialysis treatment per se has been considered to be an inflammatory stimulus, inducing cytokine production (such as interleukin-1, tumor necrosis factor-α, interleukin-6) and complement activation. The released cytokines are thought to stimulate the synthesis and release of β2M by the macrophages and/or augment the expression of human leukocyte antigens (class I), increasing β2M expression. Residual renal function is probably the best determinant of β2M levels. Therefore, it has to be maintained as long as possible. In this article, we will focus our attention on the etiology of dialysis-related amyloidosis, its prevention, therapy, and future solutions.

Destructive Spondyloarthropathy in Patients on Long-Term Peritoneal Dialysis or Hemodialysis

Destructive spondyloarthropathy (DSA) is the most serious spinal complication of dialysis-related amyloidosis in patients on long-term hemodialysis (HD), but we could not find any information about DSA in patients on peritoneal dialysis (PD) for over 10 years. We retrospectively evaluated factors contributing to DSA in HD and PD patients. Sixty-seven patients on dialysis for 10 to 19 years were compared between a PD group (n = 23) or a HD group (n = 44). In the PD group, nine patients (39%) developed DSA. The mean age of DSA patients was significantly higher than that of non-DSA patients (66.2 ± 10.0 vs. 51.0 ± 12.8 years, P = 0.03). The frequency of cervical spine DSA did not show any difference between the PD and HD groups, but the frequency of lumbar spine DSA showed a significant difference (22% vs. 5%, P = 0.04). The serum beta-2 microglobulin (B2MG) level was significantly higher in PD patients than in HD patients (38.4 mg/L vs. 27.4 mg/L, P = 0.0025). Mechanical stress such as elevation of the intra-abdominal pressure due to infusion of PD fluid (1500 mL to 2000 mL) for over 10 years might contribute to lumbar DSA in patients on long-term PD.

Pain in chronic kidney disease: a scoping review

There is increasing international attention in efforts to integrate palliative care principles, including pain and symptom management, into the care of patients with advanced chronic kidney disease (CKD). The purpose of this scoping review was to determine the extent, range, and nature of research activity around pain in CKD with the goal of (i) identifying gaps in current research knowledge; (ii) guiding future research; and (iii) creating a rich database of literature to serve as a foundation of more detailed reviews in areas where the data are sufficient. This review will specifically address the epidemiology of pain in CKD, analgesic use, pharmacokinetic data of analgesics, and the management of pain in CKD. It will also capture the aspects that pertain to specific pain syndromes in CKD such as peripheral neuropathy, carpal tunnel syndrome, joint pain, and autosomal dominant polycystic kidney disease.

Sonographic subclinical entheseal involvement in dialysis patients

Long-term dialysis treatment can be associated with several musculoskeletal complications. Entheseal involvement in dialysis patients remains rarely studied as its prevalence is underestimated due to its often asymptomatic presentation. The aims of the study were to determine the prevalence of subclinical enthesopathy in haemodialysis and peritoneal dialysis patients at the lower limb level, to investigate the inter-observer reliability of ultrasound assessment and to analyse the influence of biometric and biochemical parameters. Ultrasound examination was conducted at the entheses of the lower limbs level in 33 asymptomatic dialysis patients and 33 healthy adopting the Glasgow Ultrasound Enthesitis Scoring System (GUESS). The inter-observer reliability was calculated in 15 dialysis patients. Ultrasound found at least one sign of enthesopathy in 165 out of 330 (50%) entheses of dialysis patients. In healthy subjects, signs of enthesopathy were present in 54 out of 330 (16.3%) entheses (p < 0.0001). No power Doppler signal was detected in healthy controls, in contrast to four of 330 entheses of dialysis patients. No US signs of soft tissue amyloid deposits were found. The GUESS score was significantly higher in dialysis patients than in controls (p < 0.0001). There was no difference in terms of enthesopathy between haemodialysis and peritoneal dialysis. Dialysis duration resulted to be the most important predictor for enthesopathy (p = 0.0004), followed by patient age (p = 0.02) and body mass index (p = 0.035). Parathormone, calcium, phosphorus, C-reactive protein, cholesterol and triglycerides apparently did not play a relevant role in favour of enthesopathy. The inter-observer reliability showed an excellent agreement between sonographers with different degree of experience. Our results demonstrated a higher prevalence of subclinical enthesopathy in both haemodialysis and peritoneal dialysis patients than in healthy subjects. Follow-up will provide further information with respect to the predictive value of US findings for the development of symptomatic dialysis-related arthropathy.