Butyrylcholinesterase level as an independent factor of erythropoiesis-stimulating agent resistance in patients on maintenance hemodialysis: a single-center cross-sectional study

The First-Known Case of Hereditary Heterozygous Butyrylcholinesterase Deficiency in a Patient on Dialysis

Serum levels of butyrylcholinesterase (BChE) are commonly used to assess liver function. Its levels have been reported to be significantly lower in patients undergoing dialysis. To the best of our knowledge, this is the first report of hereditary heterozygous BChE deficiency in a patient undergoing dialysis. Medical staff involved in the care of patients with BChE deficiency should be aware of anesthetic usage, because prolonged neuromuscular paralysis following the administration of succinylcholine or mivacurium may occur. However, in the heterozygotes, BChE activity is not completely absent. Therefore, differentiating patients undergoing dialysis is challenging. A 52-year-old man underwent living-related kidney transplantation for focal segmental glomerulosclerosis at 22 years of age. As the renal function gradually worsened, the patient began to receive combined hemodialysis and peritoneal dialysis therapy. No problems with anesthesia were observed in past surgeries. The patient's BChE levels fluctuated between 76 and 170 U/L (reference range: 198-495 U/L); however, they had never been previously investigated. We suspected hereditary heterozygous BChE deficiency because the patient's sister was also diagnosed with it. DNA sequencing revealed a heterozygous missense mutation (Gly365Arg) and a K-variant (Ala539Thr). Patients on dialysis with low serum BChE levels often present with low albumin levels which may be overlooked as malnutrition. Thus, BChE deficiency should be suspected in patients on dialysis with unexplained low serum BChE levels. In the case of heterozygous BChE deficiency, the reference value is low, and continuous monitoring is crucial.

Butyrylcholinesterase level as an independent prognostic factor for overall survival in patients on maintenance hemodialysis: a single-center retrospective study

BACKGROUND

We investigated whether butyrylcholinesterase (BChE) was independently related to the overall survival (OS) of patients on maintenance hemodialysis (MHD).

METHODS

Baseline information, serum BChE level, and other laboratory data were collected from 295 patients on MHD in a single HD hospital in 2018. We retrospectively investigated the mortality of these patients after 38 months. We assessed the prognostic markers such as the Geriatric Nutritional Risk Index (GNRI), Erythropoiesis Resistance Index (ERI), and Simplified Creatinine Index (SCI) of each patient. The primary objective was to examine the impact of BChE on OS. The secondary objective included the designation of a risk score in predicting the OS.

RESULTS

We evaluated 284 patients. The median value of the serum BChE level was 206 IU/L. Of 284 patients evaluated, eighty-six patients died; all had a higher ERI and a lower serum BChE level, SCI, and GNRI than the surviving patients. The optimal cutoff values of the BChE level, GNRI, ERI, and SCI for OS were 166 IU/L, 90.0, 8.00, and 20.6, respectively. The multivariate Cox regression analysis showed that the age, HD vintage, dialysis dose, GNRI of < 90.0, and serum BChE level of < 166 IU/L (hazard ratio, 2.03; P = 0.003) were the independent prognostic factors. We designed a risk score consisting of the GNRI and serum BChE level. The predictive value of our risk score was superior to that of GNRI alone.

CONCLUSION

The serum BChE level could be an independent prognostic factor for patients on MHD.

Comparison of zinc acetate hydrate and polaprezinc for zinc deficiency in patients on maintenance hemodialysis: A single-center, open-label, prospective randomized study

The efficacy and safety of zinc acetate hydrate (ZAH) for zinc supplementation in patients on maintenance hemodialysis (MHD) remains unknown. In this prospective, single-center, open-label, parallel-group trial for MHD patients with serum zinc level <70 μg/dL, we compared ZAH (zinc; 50 mg/day) and polaprezinc (PPZ; zinc; 34 mg/day) beyond 6-month administration in a 1:1 randomization manner. The ZAH and PPZ groups had 44 and 47 patients, respectively. At 3 months, the change rate of serum zinc levels in the ZAH group was significantly higher than that in the PPZ group. Three months after the study, serum copper levels significantly decreased in the ZAH group, but not in the PPZ group. No significant differences were noted in anemia management in either group. ZAH was superior to PPZ in increasing serum zinc levels. Clinicians should note the stronger decline in serum copper levels when using ZAH for MHD patients.

Relationship between anti-erythropoietin receptor autoantibodies and responsiveness to erythropoiesis-stimulating agents in patients on hemodialysis: a multi-center cross-sectional study

BACKGROUND

A decreased response to erythropoiesis-stimulating agents (ESAs) leads to refractory anemia and worse prognosis in patients with chronic kidney disease. We examined the association between autoantibodies to the erythropoietin receptor (EPOR) and responsiveness to ESAs in patients on maintenance hemodialysis.

METHODS

A total of 108 Japanese patients on maintenance hemodialysis at three institutions were enrolled. Sera from these patients were screened for anti-EPOR antibodies using an enzyme-linked immunosorbent assay. An ESA resistance index (ERI) was calculated, and patients in the highest ERI quartile were defined as ESA hyporesponsive.

RESULTS

Anti-EPOR antibodies were detected in 11 patients (10%). Body mass index and hemoglobin, platelet, magnesium, and ferritin levels decreased with higher ERI levels. On the other hand, C-reactive protein (CRP) levels and the prevalence of anti-EPOR antibodies increased with higher ERI levels. In multivariate analysis, the presence of anti-EPOR antibodies together with CRP was a significant risk factor for ESA hyporesponsiveness.

CONCLUSIONS

Anti-EPOR antibodies were detected in patients on maintenance hemodialysis, and these autoantibodies were independent factors for hyporesponsiveness to ESAs in these patients.

Low serum butyrylcholinesterase is independently related to low fetuin-A in patients on hemodialysis: a cross-sectional study

PURPOSE

Fetuin-A, which plays a protective role against the atherosclerosis and progression of vascular calcification, is decreased in patients on hemodialysis (HD). Fetuin-A and serum butyrylcholinesterase (BChE) levels decrease during malnutrition. We explored whether BChE was independently related to fetuin-A in patients on HD.

METHODS

Laboratory data including BChE and serum fetuin-A were acquired from 230 patients on HD between August 2017 and April 2018. Nutritional status was evaluated using the Geriatric Nutritional Risk Index (GNRI). Abdominal aortic calcification index (ACI) was measured using computed tomography. Patients were stratified into two groups: low fetuin-A (< lowest quartile) and non-low fetuin-A (≥ lowest quartile) groups. Patient background, medication, and laboratory data were compared. The receiver operating characteristic analysis was conducted to determine the optimal cutoff values of BChE and GNRI for lower fetuin-A level. Factors independently related with lower fetuin-A levels were determined using multivariate logistic regression analysis.

RESULTS

The lowest quartile value of fetuin-A and optimal cutoff values of BChE and GNRI were 0.213 g/L, 200 IU/L, and 92.6, respectively. The study included 57 and 173 patients in the low fetuin-A and non-low fetuin-A groups, respectively. Significant between-group differences were observed for age, C-reactive protein (CRP), history of cardiovascular disease, serum albumin, GNRI, and BChE. Multivariate analysis showed that BChE of < 200 IU/L [odds ratio (OR) 3.05], CRP (OR 2.49), and GNRI of < 92.6 (OR 2.34) were independent factors for lower fetuin-A level after adjusting for confounders.

CONCLUSIONS

BChE was a significant independent marker for fetuin-A levels in patients on HD, in addition to GNRI.