Protein intake and its relationship with frailty in chronic kidney disease.

INTRODUCTION: Patients with chronic kidney disease (CKD) are susceptible to frailty because of a range of nutrition-related factors. While protein restriction is commonly advised to preserve kidney function in patients with CKD, insufficient protein intake could potentially exacerbate frailty risk. This study aimed to elucidate the relationship between frailty and protein intake in patients with CKD. METHODS: This cross-sectional study enrolled patients with CKD stage 3-5. Frailty and prefrailty were assessed using the Japanese version of the Cardiovascular Health Study (J-CHS) criteria. To estimate dietary protein intake, Maroni's formula based on 24-h urine collection was used. The potential association between frailty/pre-frailty and protein intake was investigated using a logistic regression analysis. RESULTS: Ninety-seven individuals with CKD were included in the study, with a median age of 73.0 years (interquartile range: 67.0, 82.0). Among them, 34 were women (35.1%), and the estimated glomerular filtration rate (eGFR) was 36.3 mL/min/1.73 m2 (interquartile range: 26.9, 44.1). Frailty and pre-frailty were identified in 13.4% and 55.7% of participants, respectively. Comparing the groups, protein intake in the frailty/pre-frailty group (0.83 g/kgBW/day [0.72, 0.93]) was lower than that in the robust group (0.89 g/kgBW/day [0.84, 1.19], p = 0.002). Upon logistic regression analysis, protein intake exhibited an independent association with frailty/pre-frailty (odds ratio: 0.72, 95% confidence interval: 0.59-0.89, p = 0.003). CONCLUSION: Reduced protein intake in patients with CKD is associated with frailty and pre-frailty. It is advisable to ensure that patients with CKD who are at risk of frailty consume an adequate amount of protein.

Feasibility of intermittent back-filtrate infusion hemodiafiltration to reduce intradialytic hypotension in patients with cardiovascular instability: a pilot study.

BACKGROUND: Intradialytic hypotension (IDH) is one of the major problems in performing safe hemodialysis (HD). As blood volume depletion by fluid removal is a major cause of hypotension, careful regulation of blood volume change is fundamental. This study examined the effect of intermittent back-filtrate infusion hemodiafiltration (I-HDF), which modifies infusion and ultrafiltration pattern. METHODS: Purified on-line quality dialysate was intermittently infused by back filtration through the dialysis membrane with a programmed dialysis machine. A bolus of 200 ml of dialysate was infused at 30 min intervals. The volume infused was offset by increasing the fluid removal over the next 30 min by an equivalent amount. Seventy-seven hypotension-prone patients with over 20-mmHg reduction of systolic blood pressure during dialysis or intervention-requirement of more than once a week were included in the crossover study of 4 weeks duration for each modality. In a total of 1632 sessions, the frequency of interventions, the blood pressure, and the pulse rate were documented. RESULTS: During I-HDF, interventions for symptomatic hypotension were reduced significantly from 4.5 to 3.0 (per person-month, median) and intradialytic systolic blood pressure was 4 mmHg higher on average. The heart rate was lower during I-HDF than HD in the later session. Older patients and those with greater interdialytic weight gain responded to I-HDF. CONCLUSIONS: I-HDF could reduce interventions for IDH. It is accompanied with the increased intradialytic blood pressure and the less tachycardia, suggesting less sympathetic stimulation occurs. Thus, I-HDF could be beneficial for some hypotension-prone patients. UMIN REGISTRATION NUMBER: 000013816.

Population pharmacokinetic analysis of thrombomodulin alfa to support dosing rationale in patients with renal impairment.

Thrombomodulin alfa is a soluble recombinant human thrombomodulin that was reported to enhance the reversal of disseminated intravascular coagulation (DIC) in subjects with sepsis or hematologic malignancy and reduce mortality in subjects with sepsis and DIC. Population pharmacokinetic (PK) analysis of thrombomodulin alfa was performed based on rich samples collected in 24 healthy subjects (0.02 and 0.06 mg/kg) and sparse samples collected in 368 subjects with sepsis and DIC (0.06 mg/kg). Sources of variability (baseline characteristics, markers of renal/liver function, hematocrit, and disease severity) were explored using non-linear mixed effect modeling to support dosing rationale in patients with sepsis and DIC. Plasma concentrations of thrombomodulin alfa were best fitted with a one-compartment model. Body weight and creatinine clearance were important covariates describing the PK of thrombomodulin alfa. Typical CL values in patients with normal renal function, or mild, moderate and severe renal impairment were 0.158, 0.145, 0.128, and 0.105 L/h, respectively. Based on simulations, a 0.06 mg/kg dosing of thrombomodulin alfa is expected to result in drug exposure within the therapeutic range of the product (300-5,400 ng/mL), with minimum risks of bleeding in patient with normal and impaired renal functions.

A case of endocapillary proliferative glomerulonephritis with macrophages phagocytosing monoclonal immunoglobulin lambda light chain.

Multiple myeloma (MM) is a plasma-cell neoplasm that can cause renal disorders. Renal lesions in MM can present with a very rare pathological manifestation involving a specific monoclonal immunoglobulin (Ig). We report the case of a 33-year-old woman who had edema, fatigue, elevated serum creatinine levels, hypoalbuminemia, and hypercholesterolemia. She had persistent hematuria and proteinuria lasting 3 years. Serum protein electrophoresis showed an M-spike, and serum immunofixation demonstrated the presence of monoclonal IgG λ. She had proteinuria in the nephrotic range, and a monoclonal λ fragment was present on urine immunofixation. Renal biopsy showed proliferative glomerulonephritis with λ light chain and C3c deposition and inflammatory cell infiltration with CD68. Macrophage lysosomes contained λ light chains, suggesting their partial phagocytosis. She was diagnosed with symptomatic MM and was treated with bortezomib and dexamethasone and an autologous peripheral stem cell transplant conditioned with intravenous melphalan. She achieved a partial response with decreased serum monoclonal protein and improved renal function. This case may be categorized as a monoclonal gammopathy-associated proliferative glomerulonephritis. The biopsy finding of partially phagocytosed Ig λ light chains by macrophages is very rare; this pathological condition is similar to crystal-storing histiocytosis.

The importance of medical interview with CKD patient in diagnoses of a family with Fabry disease.

A 47-year-old Japanese man was admitted to our hospital for evaluation of proteinuria, which was detected when he was 37 years of age. His creatinine clearance levels had fallen to 76.3 mL/min/1.73 m2. A kidney biopsy was conducted, and the patient's low plasma α-galactosidase A levels suggested Fabry disease. After genetic counseling, GLA analysis revealed a novel mutation p.L387P. Interview with the patient revealed that both his younger brother and mother suffered from cardiomyopathy and were undergoing cardiological treatment. They also were positive for proteinuria. About 30 years ago, the patient's cousin (aged 25) was diagnosed with Fabry disease. He underwent hemodialysis for 9 years until his death at 42. At that time, the patient and his brother had not been investigated for Fabry disease so their cousin could not act as a proband for the brothers. Eventually, the patient, his mother, and his brother were put on enzyme replacement therapy with agalsidase beta. As this series of cases shows, medical interviews to collate both medical and family history were essential for the discovery of Fabry disease in these patients. In addition, being a treatable genetic disorder, Fabry disease should be listed in the standard differential diagnoses of systemic and familial diseases, including unknown cause of nephropathy or cardiomyopathy, for early detection of the disorder.

A case of podocytic infolding glomerulopathy with focal segmental glomerulosclerosis.

Podocytic infolding glomerulopathy (PIG) has been proposed as a new disease entity. A 14-year-old girl underwent renal biopsy at our institution because of a chance finding of proteinuria. Light microscopic findings revealed a minor glomerular abnormality, but under a higher magnification, after periodic acid methenamine silver staining, a bubbling appearance in the glomerular basement membrane (GBM) was observed. An electron microscopic examination revealed microspheres in the GBM, which were sparse but global. The patient was diagnosed as having PIG. After 3 years, her urinary protein had increased and a second biopsy was performed, showing focal segmental glomerulosclerosis in addition to a lesser degree of podocytic infolding than at the first biopsy. This is the first report of a case complicated by a different type of glomerulonephritis after being diagnosed as PIG. A few cases of PIG are complicated by focal segmental glomerulosclerosis, suggesting several mechanisms for the disorder.

[Changes in the prognosis for survival of patients with end-stage renal disease (ESRD) treated by hemodialysis].

UNLABELLED: We started dialysis treatment in our institution in 1966, and have improved hemodialysis (HD) treatment through the induction of a biocompatible dialysis membrane, recombinant human erythropoietin, activated vitamin D and purification of the dialysate. We verified improvement of the prognosis for survival of patients with ESRD during this forty-year period, retrospectively. A total of 1,690 patients who began dialysis therapy in our hospital between January 1966 and December 2005 was studied (men: 1,047, women: 643, age: 58.6 +/- 17.4 years. They were divided into four groups (A: patients who started dialysis in the period from 1966 to 1975; n = 280, B: 1976-1985; n = 455, C: 1986-1995; n = 499, D: 1996-2005; n = 456). The mean follow-up period was 8.48 +/- 8.53 years. Of the patients 1,588 were treated with HD, 78 with peritoneal dialysis (PD), and 24 with PD or HD. Age at the initiation of dialysis increased gradually (A: 40.1 +/- 14.2 y-o, B: 53.2 +/- 15.8 y-o, C: 60.0 +/- 16.0 y-o, D: 66.4 +/- 13.8 y-o), and diabetics increased (A: 6.4%, B: 19.5%, C: 25.6%, D: 33.4%). A total of 1,180 patients died; 48.5% of these patients died of cardiovascular disease, 21.3% of infectious disease, and 6.4% of malignancy. Only 13 patients had kidney-transplants. With the Cox proportional hazard model for HD cases, age at the initiation of dialysis, gender, cause of renal disease, and the periods were significant predictors of mortality. The relative risk of mortality compared with that in A was reduced progressively: 0.796 in period B (95% confidence interval [CI]: 0.659-0.961, p = 0.0178), 0.505 in period C (95% CI: 0.409-0.623, p < 0.0001), and 0.286 in period D (95% CI: 0.223-0.366, p < 0.0001). CONCLUSIONS: Although the number of high-aged patients or diabetics with ESRD increased in these 40 years, the survival of the patients with ESRD improved.

Renal function at the time of renal biopsy as a predictor of prognosis in patients with primary AL-type amyloidosis.

BACKGROUND: Amyloid light-chain (AL)-type amyloidosis is a plasma cell disorder with a poor prognosis for survival. Although prognostic factors, such as the number of organs involved and heart function or failure in respond to therapy have been clarified based on studies including a large series of patients, there are large interindividual differences in the prognosis of patients with primary AL-type renal amyloidosis. METHODS: To clarify the prognostic factors of AL-type renal amyloidosis, we retrospectively investigated the clinical manifestations, histopathological data, and prognosis of 21 patients with amyloidosis, who had been diagnosed by renal biopsy. RESULTS: Eleven patients died, at a mean observational time of 21.7 months after renal biopsy, whereas the mean observational time was 51.0 months for the 10 patients who survived. The creatinine clearance rate was significantly higher, and the serum creatinine concentration and the grade of interstitial damage were significantly lower in surviving patients (P < 0.05). The presence of amyloid fibrils in organs other than the kidney did not influence prognosis for survival. However, the intraventricular septum was thinner in surviving patients (P < 0.1). Thirteen patients had undergone melphalan-prednisolone therapy, but it did not affect prognosis for survival. Cox proportional hazard regression analysis revealed that the renal function at the time of diagnosis was a significant and independent prognostic factor for survival. CONCLUSIONS: Our study demonstrated that renal function at the time of biopsy and renal interstitial damage are the best predictors of survival in AL-type renal amyloidosis.