End-stage renal disease versus death in a Portuguese cohort of elderly patients: an approach using competing event analysis

Chronic kidney disease (CKD) is higher in elderly, but mortality outweighs the risk of end-stage renal disease (ESRD). Our aim was to identify prognostic markers for ESRD or death in elderly CKD, within a competing-risk analysis. This is a longitudinal study of consecutive newly referred patients with CKD ages 65 years, followed until the time of the first event (ESRD or death), using a competing-risk analysis. A modified Charlson Comorbidity Index (mCCI) was subdivided into subgroups (0-2, 3-4, ≥5). Patients were followed for hospitalizations that occurred prior to the outcomes. Among 416 patients, age 76±8 years, 52% male, median estimated glomerular filtration rate of 32 mL/min per 1.73 m², 50% had diabetes, and 67% cardiovascular disease. Over a median follow-up of 3.6 years, 36 patients progressed to ESRD (8.7%) and 103 died (24.8%). Older age (subdistribution HR (sHR)=1. 06; p<0.001), creatinine≥1.6 mg/dL (sHR=2.03, p=0.004), hemoglobin <11 g/dL (sHR=1.91, p=0.003), mCCI score≥5 (sHR=3.01, p<0.001) and having one or more hospitalizations (sHR=1.73, p<0.001) were associated with death before ESRD. The independent predictors for ESRD with competing risk of death were: lower age (sHR=0.94; p=0.009), creatinine≥1.6 mg/dL (sHR=3.26, p=0.006), hemoglobin <11 g/dL (sHR=2.15, p=0.027), peripheral vascular disease (sHR=3.45, p=0.001) and having one or more hospitalizations (sHR=1.56, p=0.031). Elderly referred patients with CKD are near threefold more likely to die than progress to ESRD. A competing-risk framework based on available clinical and laboratory data may discriminate between those outcomes and could be used as a decision-making tool.

Solid organ transplantation for non-TTR hereditary amyloidosis: report from the 1st International Workshop on the Hereditary Renal Amyloidoses

Fibrinogen A α-chain (AFib) and apolipoprotein AI (AApoAI) amyloidosis due to variants in the AFib and ApoAI genes are the most common types of hereditary amyloidosis in Europe and the United States. Liver is the exclusive source of the aberrant amyloidogenic protein in AFib and responsible for supplying approximately half of the circulating variant ApoAI. Nephrotic syndrome and renal impairment due to renal amyloidosis are common disease manifestations; however, recent research provides evidence to support a more diverse and systemic disease phenotype, which in turn has implications in the management of the hereditary amyloidoses with solid organ transplantation and, in particular, liver transplantation.

The minimum Euclidean distance principle applied to improve the modulation diffraction efficiency in digitally controlled spatial light modulators

Digital addressing of the electrical signal in spatial light modulators, as it is the case in present liquid crystal on silicon (LCoS) displays, may lead to temporal phase fluctuations in the optical beam. In diffractive optics applications a reduction in the modulation diffraction efficiency may be expected. Experimental work is done characterizing the fluctuations amplitude and phase depth for three different digital addressing sequences. We propose a diffractive model to evaluate the modulation diffraction efficiency of phase diffractive optical elements (DOEs) in the presence of phase fluctuations. Best results are obtained for the most stable electrical sequence even though its phase depth is as small as 280 degrees . The results show good agreement with the numerical calculation given by the model.

Molecular characterization of human T-cell lymphotropic virus coinfecting human immunodeficiency virus 1 infected patients in the Amazon region of Brazil

The present work evaluated the epidemiology of human immunodeficiency virus 1/human T-cell lymphotropic virus (HIV-1/HTLV) coinfection in patients living in Belém (state of Pará) and Macapá (state of Amapá), two cities located in the Amazon region of Brazil. A total of 169 blood samples were collected. The sera were tested by enzyme-linked immunosorbent assay to determine the presence of antibodies anti-HTLV-1/2. Confirmation of infection and discrimination of HTLV types and subtypes was performed using a nested polymerase chain reaction targeting the pX and 5' LTR regions, followed by restriction fragment length polymorphism and sequencing analysis. The presence of anti-HTLV1/2 was detected in six patients from Belém. The amplification of the pX region followed by RFLP analysis, demonstrated the presence of HTLV-1 and HTLV-2 infections among two and four patients, respectively. Sequencing HTLV-1 5' LTR indicated that the virus is a member of the Cosmopolitan Group, Transcontinental subgroup. HTLV-2 strains isolated revealed a molecular profile of subtype HTLV-2c. These results are a reflex of the epidemiological features of HIV-1/HTLV-1/2 coinfection in the North region of Brazil, which is distinct from other Brazilian regions, as reported by previous studies.

[Comparative study of the degree of patient satisfaction in intermittent catheterization with Lofric and polyvinyl chloride catheters]

PURPOSE

To assess the grade of satisfaction in children on intermittent catheterization with the use of LoFric and PVC conventional catheters.

MATERIAL AND METHODS

A total of 40 p with experience in CIC were included in this study. An anonymous questionnaire was sent to all patients after 2-months using the LoFric catheter. Patients were divided in 3 groups (bladder augmentation, artificial sphincter, Mitrofanoff) because of major differences in CIC discomfort between these groups.

RESULTS

The questionnaire was completed by 87.5% of the patients (35 p). In 86% (30 p) LoFric catheter training was easy or very easy but in 14% (5 p) it was difficult. Four patients had some difficulty during conventional catheter insertion, in 3 (75%) the difficulty disappeared with the use of LoFric catheter. Of the 51% (18 p) who reported some discomfort during the insertion of conventional catheter, 72% said it was eliminated when the LoFric catheter was used. Of 6 p with some discomfort when removing the conventional catheter, 5 (83%) said it disappeared with the new catheter. Th LoFric catheter was favored by 70% of patients because it reduced the discomfort caused by conventional catheters, bladder insertion was easier and smoother, and gel lubrication was not needed. The 17% of patients reported some difficulty dealing with this slippery catheter.

CONCLUSIONS

The use of the LoFric catheter could be justified in patients who report with conventional catheters have some discomfort. It can also be recommended in patients with artificial sphincter, bladder augmentation and Mitrofanoff procedure, in whom any complication related to CIC would have serious consequences.

Ineffectiveness of dialysis in transthyretin (TTR) clearance in familial amyloid polyneuropathy type I, in spite of lower stability of the TTR Met30 variant

BACKGROUND

Familial Amyloid Polyneuropathy (FAP) is an hereditary form of systemic amyloidosis related to a mutant transthyretin (TTR). The renal disease ranges from proteinuria to end-stage renal failure (ESRF), with replacement of renal function by dialysis. In comparison with FAP patients with normal renal function, the progression of the neurologic disease seems to be retarded in FAP patients on dialysis.

PATIENTS AND METHODS

We evaluated the influence of hemodialysis and hemodiafiltration on plasma TTR levels in 6 FAP patients with ESRF, which were on regular hemodialysis for 4 months to 6 years, prior to this study. Hemodialysis was performed over a two-week period, one week with a cellulose triacetate membrane and the other with a polysulfone membrane. In the third week, patients were submitted to hemodiafiltration. Plasma TTR levels were measured at the beginning, 60 min, 120 min, and at the end of each session. We also evaluated the TTR adsorbed by the membrane and in the dialysate.

RESULTS

TTR levels did not change significantly with the dialysis. The total amount of TTR adsorbed to the membrane was always < 2 mg and found in the dialysate < 1 mg. Hemodialysis and hemodiafiltration were ineffective in removing TTR, in spite of lower stability of the TTR Met30 variant.

CONCLUSION

The protective feature of hemodialysis on the progression of the amyloidosis is not due to the clearance of this abnormal protein from plasma.

Hepatitis C virus genotypes and the influence of the induction of immunosuppression with anti-thymocyte globulin (ATG) on chronic hepatitis in renal graft recipients

Hepatitis C virus (HCV) exhibits a dramatic genetic variability and several mechanisms of immunological response are unable to control hepatic and extrahepatic replication. Genotype 1 b is associated with more severe clinical manifestations and is less responsive to interferon. In addition, we have reported an increase of HCV RNA viral load after renal transplantation. Anti-thymocyte globulin (ATG) is supposed to increase viral replication and liver dysfunction in chronically infected renal graft recipients. We evaluated the genotype profile in HCV+ patients of our Renal Transplant Unit and studied the effects of ATG, as part of the induction of immunosuppression, on viral load and liver enzymes abnormalities. From 726 renal graft recipients, 104 patients, with a mean follow up of 3.9 +/- 2.9 years, were anti-HCV+ by ELISA II. HCV RNA was measured by quantitative PCR. We correlated the viral load and biochemical liver parameters with genotype, exposure to ATG as induction therapy, early acute rejection episode and the duration of infection. Of the 81 patients tested, 72% were viraemic and genotype 1 b was the predominant viral strain (66%). The majority of these patients (65%) were coinfected by two or more strains. There was no correlation between HCV RNA blood levels and liver enzymes. We did not find higher viral load with genotype 1 b infection (68 +/- 88 mEq/ml vs 75.8 +/- 123 mEq/ml in the others) nor with ATG induction therapy (43.5 +/- 71.3 mEq/ml vs 64.1 +/- 110.5 mEq/ml). Early acute rejection and longer follow up were not associated with higher levels of HCV RNA. The biochemical liver profile showed no relationship with the variables studied. We concluded that genotype 1 b is the predominant strain in our HCV+ population and there is a great prevalence of coinfection with several genotypes. Our results did not confirm a deleterious effect of the use of ATG as induction therapy in these HCV-infected patients. Prospective randomised studies with liver biopsy evaluation are needed to answer more fully the remaining questions about the best immunosuppressive therapy in renal graft recipients with chronic HCV infection.

Familial amyloid polyneuropathy type I (Portuguese): distribution and characterization of renal amyloid deposits

Renal amyloidosis has been considered rare and late in the evolution of the transthyretin (TTR) familial amyloid polyneuropathy (FAP) of the Portuguese type (type I). Renal biopsy has been performed systematically in 14 patients with FAP type I before liver transplantation. In all patients, TTR Met30 mutation was shown. Seven had proteinuria or abnormal microalbuminuria, whereas seven others had no urinary abnormalities. All had renal amyloid deposition predominantly in the medulla. Glomerular and vascular involvement was more prominent in patients with urinary abnormalities. Patients with the most extensive renal lesions represented a subgroup with a low score of polyneuropathy disability, a high prevalence of nephropathy in the proband generation, or a late onset for relatives with nephropathy. Immunohistochemistry studies showed that the amyloid substance corresponded to transthyretin. We have shown that renal TTR-derived amyloid deposition is common in patients with FAP type I, even in the absence of urinary abnormalities. The clinical presentation of nephropathy is not a late occurrence in the disease.

Maternal and perinatal implications of the use of human recombinant erythropoietin

BACKGROUND

The use of human recombinant erythropoietin (rHuEPO) in pregnant patients has been limited by the fear of eventual maternal and fetal repercussions (either direct or indirect).

METHODS

The authors present their experience with the use of rHuEPO during pregnancy, with two pregnant women with kidney transplants and in three others with chronic renal insufficiency (one with diabetic nephropathy, another dialysis dependent), all with hematocrit below 30% and adequate iron reserves.

RESULTS

Three of the patients had needed blood transfusions before beginning therapy, and another needed transfusion after significant metrorrhagia. The length of the treatment varied between 2 and 23 weeks and the hematocrit at delivery varied between 26% and 36%. Secondary effects (appearance or worsening of hypertension and seizures) were nil. There was one fetal death at 23 weeks of pregnancy (following an abruptio placenta), two neonates weighing between the 5th and the 10th percentiles, and three needing phototherapy (1 to 2 days). One year after birth, all showed a normal ponderal and neurologic development.

CONCLUSIONS

Among the cases presented, no maternal and perinatal complications attributable to rHuEPO were registered. It is important that institutions report their experiences with the use of rHuEPO, given its restrictive indications and the limited experience of each institution.

Cytogenetics of the South American akodont rodents (Cricetidae). IX. Chiasmatic sex bivalent in male meiosis of Akodon mollis

Akodon mollis (Rodentia, Cricetidae) has a large subterminal Y chromosome measuring 5.24 percent of the haploid set. The long arm of the Y has a pattern of homology with the short arm of the X, as indicated by the similar distribution of G bands and by the formation of a chiasma in diakinesis and metaphase I of teste cells. Conversely, the short arm of the Y and the long arm of the X are nonhomologous and do not pair at meiosis.