Carbamylated hemoglobin in hemodialysis patients

Tarif, Nauman; Shaykh, Mashouf; Stim, James; Arruda, José A.L.; Dunea, George

doi:10.1016/s0272-6386(97)90280-8

Cited by 24 publications

(12 citation statements)

References 11 publications

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“…106 Several subsequent studies have confirmed this. 107-110 It was later shown in a small cohort of dialysis subjects (n=55) that carbamylated hemoglobin is higher in individuals with Kt/V < 1.1 than in those with a Kt/V greater than this; also, as predicted, carbamylation level correlates negatively with both Kt/V and urea reduction ratio. 111 Others have similarly demonstrated carbamylated hemoglobin could be a more accurate indicator of average urea between hemodialysis sessions than the standard indices of dialysis adequacy, Kt/V and URR.…”

Section: Pathogenesismentioning

confidence: 90%

“…111 Others have similarly demonstrated carbamylated hemoglobin could be a more accurate indicator of average urea between hemodialysis sessions than the standard indices of dialysis adequacy, Kt/V and URR. 110,112 In contrast, in a study limited by sample size (n=7), Balion et al found significant variability over time in individuals’ carbamylated hemoglobin levels, with little association with markers of dialysis adequacy. 46 …”

Section: Pathogenesismentioning

confidence: 91%

See 1 more Smart Citation

Protein Carbamylation in Kidney Disease: Pathogenesis and Clinical Implications

Kalim

Karumanchi

Thadhani

et al. 2014

American Journal of Kidney Diseases

107

101

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Carbamylation describes a non-enzymatic, posttranslational protein modification mediated by cyanate, a dissociation product of urea. When kidney function declines and urea accumulates, the burden of carbamylation naturally rises. Free amino acids may protect proteins from carbamylation, and protein carbamylation has been shown to increase in uremic patients with amino acid deficiencies. Carbamylation reactions are capable of altering the structure and functional properties of certain proteins, and have been directly implicated in the underlying mechanisms of various disease conditions. A broad range of studies has demonstrated how the irreversible binding of urea-derived cyanate to proteins in the human body causes inappropriate cellular responses leading to adverse outcomes such as accelerated atherosclerosis and inflammation. Given carbamylation’s relationship to urea and the evidence that it contributes to disease pathogenesis, measurements of carbamylated proteins may serve as useful quantitative biomarkers of time-averaged urea concentrations while also offering risk assessment in patients with kidney disease. Moreover, the link between carbamylated proteins and disease pathophysiology creates an enticing therapeutic target for reducing the rate of carbamylation. This article reviews the biochemistry of the carbamylation reaction, its role in specific diseases, and the potential diagnostic and therapeutic implications of these findings based on recent advances.

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Section: Pathogenesismentioning

confidence: 90%

Section: Pathogenesismentioning

confidence: 91%

Protein Carbamylation in Kidney Disease: Pathogenesis and Clinical Implications

Kalim

Karumanchi

Thadhani

et al. 2014

American Journal of Kidney Diseases

107

101

View full text Add to dashboard Cite

show abstract

“…In contrast, measurement of carbHb requires only a single measurement in one blood sample that could be performed easily in a clinical laboratory, making carbHb a particularly simple and technically reliable index for the assessment of uremic control. We found significant but weak negative correlations between carbHb and K t /V or URR (table 3), although it has been controversial [14, 24, 25]. We presumed that both K t /V and URR could be conventionally used to assess the efficacy of a single HD session, while carbHb reflects uremic control over a relatively long interval.…”

Section: Discussionmentioning

confidence: 89%

Carbamylated Hemoglobin as a Therapeutic Marker in Hemodialysis

Hasuike

Nakanishi²,

Maeda³

et al. 2002

Nephron

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Carbamylation requires isocyanic acid derived from urea. Carbamylation of hemoglobin (Hb) produces carbamylated Hb (carbHb), which could serve as a marker of posttranslational protein modification possibly associated with such uremic complications as atherosclerosis. Since relative carbHb levels are determined by mean urea concentration and duration of exposure, they could be used to assess the adequacy of a patient’s hemodialysis (HD) regimen. We therefore determined the relationship between carbHb and urea kinetics in patients with chronic renal failure (CRF) undergoing maintenance HD. In pre-HD determinations as well as in nondialyzed subjects including healthy subjects and CRF patients without dialysis, carbHb correlated well with blood urea nitrogen (BUN) concentrations, especially with BUN averaged for the preceding 1–3 months. In HD patients, carbHb correlated significantly with urea kinetics (time-averaged concentration of urea, or TAC_urea, K_t/V and urea reduction rate). The estimated mean urea concentration in HD patients calculated from the relationship between carbHb and averaged BUN over 3 months in the nondialyzed groups was lower than TAC_urea, suggesting that TAC_urea may be an overestimate. Pre-HD BUN is not a good nutritional index since detrimental decreases in urea elimination from the body can elevate pre-HD BUN independently of nutrition. We therefore devised a new nutritional index, BUN/carbHb, which correlated significantly with serum albumin as well as the normalized protein catabolic rate. These results demonstrate that carbHb accurately reflects uremic control and the BUN/carbHb ratio could serve as an index of nutritional state in HD patients.

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“…No correlations were observed between these two parameters, whereas cHb was previously found to be associated with Kt/V values [5,6]. However, the results associating cHb and Kt/V were somewhat controversial [22,25,26]. In addition, Kt/V index has been questioned about its ability to provide relevant information on dialysis efficiency [27][28][29].…”

Section: Discussionmentioning

confidence: 99%