|
|
Year : 2010 | Volume
: 21
| Issue : 4 | Page : 701-706 |
|
Beta-2 Microglobulin Levels in Hemodialysis Patients |
|
Asim Mumtaz1, Muhammad Anees2, Muhammad Bilal3, Muhammad Ibrahim4
1 Department of Chemical Pathology, University of Health Sciences, Lahore, Pakistan 2 Department of Nephrology, King Edward Medical University, Lahore, Pakistan 3 Allied Health Sciences, University of Health Sciences, Lahore, Pakistan 4 Department of Statistics, Govt. Diyal Singh College, Lahore, Pakistan
Click here for correspondence address and email
Date of Web Publication | 26-Jun-2010 |
|
|
 |
|
Abstract | | |
The objective of the study was to determine the level of β2-microglobulin (β2-m) in hemodialysis (HD) patients and the factors affecting it. This cross sectional, hospital based study was conducted between September and December 2008 at the Hemodialysis unit of Shalamar Hospital, Lahore. All patients with end-stage renal disease (ESRD) who were on maintenance HD for more than three months were included in the study. Patients with acute renal failure and on dialysis for less than three months were excluded. Demographic data were collected and details of dialysis (type of dialyzers, dialysate bath, membrane used) were recorded. Blood samples of the patients were drawn for hematological (hemoglobin, hematocrit), biochemical (urea, creatinine, uric acid, albumin) and β2-m level measurement. The total number of patients studied was 50. The major causes of ESRD included diabetes mellitus and hypertension seen in 37 (74%) and 10 patients (20%), respectively. The β2-m levels were significantly elevated in the study patients; 92.6 ± 17.1 mg/L with a range of 54 to 130 mg/L as compared to 2.0 ± 1.29 mg/L in the control group. The patients' age had a statistically significant relationship with the β2-m level. The major reason for increased β2-m level was use of low-flux dialyzers. Synthetic polysulphone membrane, bicarbonate, ultra pure dialysate and duration on HD were not associated with high β2-m levels. Also, we found an inverse relationship between β2-m levels and serum albumin of the study patients. Our study suggests that the β2-m levels are significantly high in dialysis patients. Use of low-flux dialyzer seems to be the major reason for the high β2-m levels. Age and albumin have statistically significant relationship with β2-m levels.
How to cite this article: Mumtaz A, Anees M, Bilal M, Ibrahim M. Beta-2 Microglobulin Levels in Hemodialysis Patients. Saudi J Kidney Dis Transpl 2010;21:701-6 |
How to cite this URL: Mumtaz A, Anees M, Bilal M, Ibrahim M. Beta-2 Microglobulin Levels in Hemodialysis Patients. Saudi J Kidney Dis Transpl [serial online] 2010 [cited 2022 May 23];21:701-6. Available from: https://www.sjkdt.org/text.asp?2010/21/4/701/64652 |
Introduction | |  |
B2-microglobulin (β2-m), the non-polymorphic chain of the major histocompatibility Class I complex (MHC-I), is found on the surface of all nucleated cells and plays a central role in cellular immunology. Its synthesis rate normally ranges from 2-4 mg/kg/day with a half life of 2-5 hours. [1] In healthy individuals, the plasma concentration varies from 1 to 3 mg/L which varies inversely with the glomerular filtration rate (GFR). More than 95% of β2-m is eliminated by degradation in the proximal tubule. Since this compound cannot be removed from the serum by the kidney or certain dialysis membranes in patients with renal dysfunction on dialysis, β2-m concentration is increased by up to 60-fold in patients with end-stage renal disease (ESRD). [2] Accumulation of β2-m in these patients lead to Dialysis-Related Amyloidosis (DRA). In general, it becomes apparent only after more than 5-7 years of renal replacement therapy. This type of amyloid may be seen even in patients with long-standing, severe renal failure who are not yet treated by dialysis or related procedures. [3] Age above 40years at the start of dialysis, [4] duration of dialysis, [5] use of cuprophane and low-flux membranes and use of low purity dialysate are identifiable risk factors. β2-m-related amyloid has a marked affinity for joint tissues (cartilage, capsule, synovium). The main signs and symptoms of DRA are musculoskeletal disorders such as carpal tunnel syndrome, joint arthro-pathy, and bone cysts leading occasionally to pathologic bone fractures. After long-term dialysis therapy, extra-articular symptoms such as ischemic colitis, amyloid tumor, heart failure with pulmonary hypertension, gastrointestinal tract bleeding, can also occur. β2-m is an important predictor of mortality in dialysis patients. According to Okuno S et al, [6] Kaplan-Meier analysis revealed that all-cause mortality in the higher β2-m group (≥ 32.2 mg/L) was significantly higher compared to that in the lower β2-m group (≤ 32.2 mg/L) (P < 0.001). AK Cheung et al, [7] in the HEMO study, reported that the pre-dialysis serum β2-m level predicted mortality. There was 11% increase in mortality for each 10 mg/L increase in β2-m level even after adjustment for years on dialysis and residual kidney function. Clinical therapeutic strategies for DRA include dialysis, medical or surgical therapy and renal transplantation. Renal transplantation usually leads to symptomatic improvement within days, likely related to use of steroids and immunosuppressive therapy. [8] In Pakistan, due to paucity of indigenous research, β2-m levels in hemodialysis (HD) patients is not known. Hence, this cross-sectional study was conducted to check the levels of β2-m among patients on HD as well as factors affecting it.
Materials and Methods | |  |
This study was conducted at the HD unit of Shalimar Hospital, Lahore from January to April 2008. All patients with ESRD, who were on regular HD for more than three months were included in the study. The study patients were informed about the study and consent was obtained. Patients with acute renal failure and those with ESRD on HD for less than three months were excluded from the study. Demographic data including age, sex, cause of ESRD, HBsAg and Anti-HCV status as well as details of dialysis (dialysate bath, porosity of dialyzers and dialyzer membrane) were recorded. Pre-dialysis blood sample of the patients was drawn to measure hematological (hemoglobin and hematocrit) and biochemical parameters (urea, creatinine, albumin and uric acid) and β2-m levels. Fifteen normal individuals were included as controls.
Statistical Analysis | |  |
The data were analyzed by using standard SPSS software version-16 (SPSS Inc, Chicago) for statistical analysis. Mean ±SD is given for quantitative variables including blood urea, serum creatnine, serum uric acid, serum albumin, serum β2-m, blood hemoglobin and hematocrit. Levene's test was applied for Equality of Variances. A P-value of < 0.05 was considered statistically significant.
Results | |  |
The total number of patients who were on maintenance HD for more than three months was 50. The major cause of ESRD was diabetes mellitus followed by hypertension as shown in [Table 1] and the mean duration on dialysis was 13.82 months with a range of three to sixty months. Majority of the patients were anti-HCV and HbsAg negative. All the study patients were being dialyzed using lowflux synthetic membrane dialyzers and bicarbonate dialysate bath. Hematological and biochemical data of patients and controls are shown in [Table 2]. The mean β2-m level was 92.6 mg/L with a range of 54 to 130 mg/L.
Discussion | |  |
Dialysis is the process of separation of soluble substances from colloids and their removal through a semi-permeable membrane, down a concentration gradient. Currently, more than one million patients worldwide undergo either HD or PD to maintain life. [9] However, dialysis does not restore all renal functions. [10] Uremic toxins are classified as small molecular weight and middle molecules (substances with a molecular weight between 0.5 and 2 kDa) as well as large peptides, which are normally excreted or metabolized by the healthy kidney. These middle molecules will accumulate in chronic HD patients if they are being dialyzed with low quality membranes [Figure 1].
In this study, the β2-m levels were significantly elevated (P = 0.001) compared to control subjects. Similar high levels was observed by Mario T et al [11] (42.14 ±14 mg/L), Kuchle et al (51 ±11 mg/L) [12] and T Jeloka et al. [13] AK Cheung [14] also found that the cumulative mean pre-dialysis serum β2-m level was significantly lower with use of high-flux dialyzers than with low-flux dialyzers (33.6 versus 41.5 mg/L).
The major reason for such a high level of β2m in this study was that the dialyzer used for HD in our patients was of the low-flux type. As β2-m is a middle molecule of molecular weight of 12000 Da, conventional, low-flux dialyzers do not clear these molecules which lead to accumulation of this silent killer in the body. Financial constrains are the major reason for using low-flux dialyzers in our patients. The cost of dialysis when low-flux dialyzers are used is about US Dollars 400 as against the cost for using high-flux HF dialyzers, which is about 50 US Dollars more. This factor is the major reason for using low-flux dialyzers and accumulation of β2-m in these patients.
The clearance of β2-m with different dialyzers after three and half hours of dialysis is depicted in [Figure 2]. There was almost no clearance with low-flux dialyzers; however, high-flux dialyzers F60, Primus 1350, BioCare130 gave clearance of β2-m of 50%, 60% and 64%, respectively.
Bio-incompatibility of dialyzers plays an important role in accumulation of β2-m in these patients. Depending on the type of dialyzers used, blood-membrane contact results in the generation of the complement activation products C3a and C5a, which elicit important physiological reactions, such as changes in the expression of adhesion molecules on peripheral blood mononuclear cells and polymerphonuclear cells. [15],[16],[17] In our dialysis setup, we use dialyzers of synthetic membranes material (polysulfone) which are biocompatible than previously used cellulose-based dialyzers. Thus, dialyzer membranes probably had no role to play in causing the high level of β2-m in these patients. Ferreira A et al [18] reported that the serum β2-m level was higher in patients dialyzed with cellulosebased dialyzers (59.8 ±14.1 mg/L) than synthetic high-flux dialyzers (32.8 ±8.7 mg/L).
The dialysate bath is another factor that can cause increased β2-m level in these patients. Microbiological purity and/or the use of bicarbonate buffer appear to be associated with a decreased prevalence of amyloidosis. [19],[20] In our dialysis unit, bicarbonate is used as dialysate bath and ultra pure water for dialysis. We have Fresenius Medical Care, Germany, hemodialysis machines which have inbuilt Diasafe filters which make the water ultra pure. Along with this, the quality of water of our dialysis unit is checked on regular basis and it is free from any contaminants. Thus, in our patients, dialysate bath and water probably did not play any role in β2-m accumulation. Similar observations have been reported by Furuya R et al. [21] According to them, switching from conventional to ultra pure dialysate significantly decreased plasma levels of β2-m from 30.1 ±1.4 to 27.1 ±1.4 mg/L (P < 0.05) after one month of use.
Apart from the variables described above, even the type of dialysis delivered like hemodiafiltration (HDF) and hemofiltration (HF) are better for removal of β2-m than standard diffusive HD. Economic constrains is an important factor for not using these modalities for dialysis. Also, modalities such as HDF and HF are not available in routine hemodialysis machines. According to Willy Lorny et al, [22] during HDF with online replacement of solution at a rate of 100 mL/min, clearance of β2-m was 116.8 mL/min as against 63.8 mL/min on conventional HD (P = 0.0000).
The duration on HD treatment plays an important role in the development of DRA. [23],[24],[25] For the development of clinical effects of β2m, more than five to seven years are required. However, a recent, large scale post mortem study showed that incipient dialysis related amyloid deposits occur in as many as 21% of cases within two years, and in 33% of cases within four years, which increased to 100% in patients treated for more than 13 years after the start of renal replacement therapy. [23],[24],[25],[26] In our study patients, there were no clinical manifestations of DRA due to raised β2-m levels such as carpel tunnel syndrome, joint arthropathy and fractures. But in this study, mean duration on dialysis was one year and three months with range of 3 to 60 months. This short duration on dialysis may be the reason for not affecting the synovial membranes although histopathological confirmation of beta-2m deposition with Congo red stain was not obtained.
Age at the onset of dialysis plays an important role in the development of DRA. In this study, age had a statistically significant positive correlation with β2-m level. Similar findings were observed by Van Ypersele et al. [4] According to them, age at onset of dialysis was found to have a striking correlation with the development of carpal tunnel syndrome and bone amyloidosis.
Albumin is used for routine nutritional assessment in dialysis patients. Hypoalbuminemia is a very important predictor for morbidity and mortality of dialysis patients. [27] In this study, mean serum albumin was 3.24 ±g/L with range of 1.9 to 5.4 g/L. Majority of the patients (74%) had low serum albumin (< 3.8 g/L) and serum albumin level had a significant negative correlation with 132-m levels. This negative correlation supports the direct effect of both of these parameters on the mortality of dialysis patients. According to Cianciolo G et al, [28] Cox analysis for carpal tunnel syndrome confirmed serum albumin (RR 0.59, P < 0.0001) and residual GFR (RR 0.75, P < 0.0001) as protective factors.
Conclusion | |  |
Our study suggests that β2-m levels are significantly high in dialysis patients. Use of lowflux dialyzer seems to be the major reason for the high levels of β2-m. Age has positive correlation and albumin has negative correlation with β2-m levels.
Limitations
Our study had a few limitations as follows:
- It was a cross-sectional design and the predialysis β2-m levels were not measured in patients with chronic kidney disease.
- We have not compared the effect of highflux dialyzers on the level of β2-m.
- For determination of the effect of β2-m level on the tissues, x-rays and histopathological analysis was not done.
References | |  |
1. | Kleinman KS, Coburn J, Amyloid syndromes associated with hemodialysis. Kidney Int 1989;35:567-75. |
2. | Floege J, Ehlerding G. Beta 2-microglobulin associated amyloidosis. Nephron 1996;72:9-26. |
3. | Jadoul M, Garbar C, Noel H, et al. Histological prevalence of β2m amylodosis in hemodialysis patients: A prospective postmortem study. Kidney Int 1997;51:1928-32. |
4. | Van Y, Persele de Strihou C, Jadoul M, Malghern J, Maldague B, Jamart J. Effect of dialysis membrane and patient's age on signs of dialysisrelated amyloidosis. The Working Party on Dialysis Amyloidosis. Kidney Int 1991;39(5):1012-9. |
5. | Hurst NP, van den Bergh R, Disney A, et al. Dialysis related arthropathy: a survey of 95 patients receiving chronic hemodialysis with special reference to beta 2 m related amyloi-dosis. Ann Rheum Dis 1989;48:409-20. |
6. | Okuno S, Ishimura E, Kohno K, et al. Serum beta 2-micrglobulin is a significant predictor of mortality in maintenance of hemodialysis patients. Nephrol Dial Transplant 2009;24(2):571-7. |
7. | Cheung AK, Rocco MV, Yan G, et al. Serum Beta-2 Microglobulin Levels Predict Mortality in Dialysis Patients: Results of the HEMO Study. J Am Soc Nephrol 2006;17:546-55. |
8. | Jadoul M, Dnueket T, Zingraff J, Van Ypersele DE, Strihou C. Does dialysis related arnyloi-dosis regress after renal transplant? Nephrol Dial Transpl 1997;12:655-7. |
9. | US Renal Data System. USRDS 2004.Annual data report atlas of end stage renal disease in the United State 2004.NIH.National Institute of Diabetes and Digestive and Kidney Disease, Bethesda,MD. |
10. | Erkan D, Yonca A, Sarper E, Gur A, Ahmad Y. Beat 2 m amyloidosis in hemodialysis and peritoneal dialysis patients. Therap Apheresis Dial 2008;12(4):306-10. |
11. | Traut M, Haufe CC, Eismann U, Deppisch RM, Stein G, Wolf G. Increased binding of Beta-2Microglobulin to blood cells in dialysis patients treated with high-flux dialyzers compared with low-flux membranes contributed to reduced Beta2-microglobulin concentrations. Blood Purif 2007; 25:432-40. |
12. | Kuchle C, Fricke H, Held E, Schiff H. High-flux hemocialysis postpones clinical manifestation of dialysis-related amyloidosis. Am J Nephrol 1996; 16(6):484-8. |
13. | Jeloka T, Mathur G,, Kaur R, Kohli R, Singh NP, Rizvi SN. β2 Microglobulin in chronic renal failure and effect of different dialyzer membrane on its clearance. Indian J Nephrol 2001,11:160-4. |
14. | Cheung AK, Greene T, Leypoldt JK, et al. Association between serum 2-microglobulin level and infectious mortality in hemodialysis patients. Clin J Am Soc Nephrol 2008;3:69-77. |
15. | Grooteman MP, Nube MJ. Haemodialysis-related bioincompatibility: fundamental aspects and clinical relevance. Neth J Med 1998;52: 169-78. |
16. | Horl WH. Hemodialysis membranes: Interleukins, biocompatibility, and middle molecules. J Am Soc Nephrol 2002;13: S62-71. |
17. | Lonnemann G. Should ultra-pur6e dialysate be mandatory. Nephrol Dial Transplant 2000;15 (Suppl 1):55-9. |
18. | Ferreira A, Urena P, Ang KS, et al. Relation-ship between serum beta 2-microglobulin, bone histology, and dialysis membranes in uraemic patients. Nephrol Dial Transplant 1995;10(9): 1701-7. |
19. | Lonnemann G, Koch KM. β2-Microglobulin amyloidosis: Effects of ultrapure cialysate and type of dialyzer membrane. J Am Soc Nephrol 2002; 13:S72-7. |
20. | Arizono K, Nomura K, Motoyama T, et al. Use of ultrapure dialysate in reducetion of chronic inflammation during hemodialysis. Blood Purif 2004;22(suppl 2):26-9. |
21. | Furuya R, Kumagai H, Takahashi M, Sano K, Hishida A. Ultrapure dialysate reduces plasma levels of beta2-microglobulin and pentosidine in hemodialysis patients. Blood Purif 2005;23(4): 311-6. |
22. | Lorny W, Because J, Billiouw JM, Sierens L, Van Malderen P. Remarkable removal of beta-2 microglobulin by on line hemodiafiltration. Am J Nephrol 1998;18:105-8. |
23. | Al-Taee IK, Al-Safar JJ, Al-Falahi YS, AlShamma IA. The clinical significance of β2-microglobulin in end-stage renal disease. Saudi J Kidney Dis Transpl 2003;14(4):492-6. |
24. | McCarthy JT, Williams AW, Johnson WJ. Serum beta 2-microglobulin concentration in dialysis patients: importance of intrinsic renal function. J Lab Clin Ivied 1994;123(4):495-505. |
25. | Alhomrany MA, Khan MR, Adzaku F, Harding MG. Carpel tunnel syndrome in hemodialysis patients: Early detection by electroneurophysiological studies. 2001;6(6): 259-62. |
26. | Dixit MP, Cabansag MR, Piscitelli J, Greifer I, Silverstein DM. Serum beta2-microglobulin and immunoglobulin levels in young hemodialysis patients. Pediater Nephrol 1999;13(2):139- 42. |
27. | Collins AJ, Ma JZ, Umen A, Keshaviah P. Urea index and other predictors of long-term outcome in hemodialysis patients survival. Am J Kidney Dis 1994;20:32-8. |
28. | Cianciolo G, Coli L, La Manna G, et al. Is beta 2microglobulin-related amyloidosis of hemodialysis patients a multifactorial disease? A new pathogenetic approach. Int J Artif Organs 2007; 30(10):864-78. |

Correspondence Address: Muhammad Anees 726-L, M A Johar Town, Lahore Pakistan
 Source of Support: None, Conflict of Interest: None  | Check |
PMID: 20587875  
[Figure 1], [Figure 2]
[Table 1], [Table 2] |
|
This article has been cited by | 1 |
Serum S100B protein is associated with depressive symptoms in patients with end-stage renal disease |
|
| Kim, J.-K. and Kim, S.G. and Kim, H.J. and Song, Y.R. | | Clinical Biochemistry. 2012; 45(18): 1573-1577 | | [Pubmed] | | 2 |
Disseminated amyloidosis presenting with right proximal femur pathological fracture in a haemodialysis end-stage renal failure patient |
|
| Chan, A.P.H. and Cheung, T.C.Y. and Cheung, S.Y. and Ho, E.P.Y. and Fan, J.C.H. and Wang, K. and Fung, K.Y. | | Hong Kong Medical Journal. 2011; 17(6): 495-499 | | [Pubmed] | |
|
|
 |
 |
|
|
|
|
|
|
Article Access Statistics | | Viewed | 8888 | | Printed | 112 | | Emailed | 0 | | PDF Downloaded | 1208 | | Comments | [Add] | | Cited by others | 2 | |
|

|