Long-term renal graft function and survival in patients with high-risk for cytomegalovirus infection receiving preemptive therapy

BACKGROUND

Preemptive therapy reduces the risk of cytomegalovirus disease in high-risk kidney transplant patients. The advantage of this strategy is that only a fraction of patients receive antiviral drugs for a limited time, which decreases costs and toxicity but requires frequent monitoring and may not prevent complications of asymptomatic cytomegalovirus replication.

MATERIAL AND METHODS

Long-term graft-function and patient survival of high-risk kidney transplant patients who received preemptive therapy guided by pp65 antigenemia was compared to those whose assay remained negative throughout the first post-transplant year.

RESULTS

Between August 1997 and March 2005, 24 of 272 patients were CMV D+/R-. Thirteen of the 24 (54.2%) developed a positive CMV assay during follow-up; the time between transplant and first positive antigenemia was 66.7 +/- 58.3 days (range 29-251 days). Four patients developed symptoms associated with CMV, one of whom succumbed from complications of CMV neumonitis. Overall, no significant differences were observed in SCr, eGFR, delta SCr, and delta eGFR during a 60-month followup between patients who developed CMV infection or disease and those who remained pp65 antigenemia-negative throughout the first 12 post-transplant months. Additionally, no deaths or graft loss occurred during the long-term follow up of this cohort.

CONCLUSIONS

Our results suggest that in this high risk group of kidney transplant recipients, treating CMV replication using a preemptive strategy during the first posttransplant year is associated with a low rate of CMV complications and probably interferes with the alleged long-term negative indirect effects of CMV on kidney function and survival.

Screening for Tuberculosis in the Study of the Living Renal Donor in a Developing Country

Given the high prevalence of tuberculosis (Tb) in the Mexican population, a strict program to detect Tb in the potential donor is required. Chest x-ray, excretory urogram, urinalysis with microscopic exam of the sediment, urine cultures for M. tuberculosis, and tuberculin skin test (TST) with PPD-RT23 performed for evaluation of 222 living donors were reviewed. Isoniazid prophylaxis before kidney donation was gathered. Donors and recipients were followed up for a minimum of 2 years. According to the TST result, 36.8% of the donors had latent tuberculosis; however, all other studies were normal or negative in all of them. Use of isoniazid prophylaxis in TST-positive donors made no difference in risk of transmission of tuberculosis to the recipient or development of tuberculosis among the donors. Normal chest x-ray and excretory urogram, along with a negative microscopic examination of the urine, safely exclude tuberculosis transmission to recipients.

Early detection and prevention of diabetic nephropathy: a challenge calling for mandatory action for Mexico and the developing world

During the last decades, developing countries have experienced an epidemiologic transition characterized by a reduction of infectious diseases and an increase of chronic degenerative diseases. This situation is generating tormenting public health, financial, and social consequences. Of particular relevance is type 2 diabetes mellitus and its chronic complications, particularly cardiovascular disease and diabetic nephropathy, because mortality of the patient with diabetes is, in most instances, related to these complications. There is a clear need to implement diagnostic and treatment strategies to reduce risk factors for development of diabetes (primary prevention), to detect risk factors of chronic complications in early stages of diabetes (secondary prevention), and to prevent further progression of those that already have renal injury (tertiary prevention). Microalbuminuria is an early marker of renal injury in diabetes, and its early detection can help the timely use of renal preventive measures, which would avoid the extremely high costs of renal replacement treatment for end-stage renal disease as well as that of other cardiovascular complications. Preventive strategies are of very little or no impact, if the primary physician has limited knowledge about the natural history of diabetic nephropathy, the beneficial effect of early preventive maneuvers for delaying its progression, and the social and economic impact of end-stage renal disease. It is therefore imperative to assure in our health systems that general practitioners have the ability and commitment to detect early diabetes complications, in order to promote actions that support regression or retard highly morbid cardiovascular and renal conditions.

Insulin subcutaneous application vs. continuous infusion for postoperative blood glucose control in patients with non-insulin-dependent diabetes mellitus

BACKGROUND

Frequently, the use of insulin is considered for metabolic control in postoperative patients with non-insulin-dependent diabetes mellitus (NIDDM). We sought to determine the best method for control of glucose in NIDDM non-insulin patients during postoperative care.

METHODS

Two algorithms were developed: subcutaneous administration of insulin (SC), and continuous intravenous infusion (IV). A randomized, controlled clinical trial was designed. In addition, both experimental groups were compared with a non-concurrent routinely managed group (RM) with insulin administration under no predetermined algorithm. Eligible patients were those subjected to major surgery under general anesthesia or spinal blockade. They were followed for 48 h after surgery. Target variables were capillary and central blood glucose, insulin dose administered, urine glucose and ketone strip determination, and development of hyper- or hypoglycemia.

RESULTS

A total of 62 patients were studied (RM = 25, SC = 19, IV = 18). Results for both experimental algorithms were similar except for the IV group that required less insulin per hour compared to SC (0.64 vs. 0.34 U/h; p = 0.0003). The RM control group showed poor control in all capillary glucose measurements (194.9 +/- 26.8 mg/dL) compared with the two experimental algorithms (SC = 129.9 +/- 21; IV = 131.6 +/- 20.4) (p <0.05). More hyperglycemia events appeared in the RM group (p = 0.016). Only one hypoglycemia event occurred in the IV group.

CONCLUSIONS

Postoperative control of NIDDM is similar with both tested methods. The use of any of the algorithms studied improves metabolic control substantially because it standardizes postoperative management of the diabetic patient with timely determination of capillary blood glucose and insulin administration. However, IV administration has the advantage of accomplishing adequate control with a smaller insulin dose.

[Viral hepatitis C in patients with terminal chronic renal insufficiency. III. Viral quantification]

BACKGROUND

We have previously shown that the prevalence of hepatitis associated with the hepatitis C virus (HCV) in patients with end stage renal disease in our institution is 10.2%. However, quantification of viral RNA in plasma and its relation with clinical variables has never been studied in our patients. Thus, the aim of the present work was to quantify the HCV viral load in patients with ESRD in dialysis, and to correlate these values with the dialysis modality and the viral genotype.

METHODS

We performed a transverse, prospective and comparative study in patients with HCV infection in hemodialysis, continuous ambulatory peritoneal dialysis and patients in peritoneal dialysis, but with history of hemodialysis. Viral load was quantified with RT-PCR by using a commercial kit known as Amplicor HCV 2.0. Clinical variables studied were: age, gender, end stage renal disease etiology, modality and time in dialysis, transfusions, serum albumin, aminotransferases, blood urea nitrogen, and serum creatinine.

RESULTS

Twenty four patients in dialysis with HCV infection entered into the study. Of these patients, 25% were on peritoneal dialysis, 29% on peritoneal dialysis with history of hemodialysis, and 46% were in hemodialysis. The average viral load (copies x 10(6)/mL) was 1.41 +/- 3.01. Viral load was lower in patients on peritoneal dialysis than in patients treated, or with history of hemodialysis (0.20 +/- 0.12 vs 2.04 +/- 0.88; p < 0.05). We observed no differences in viral load among patients with different viral genotypes.

DISCUSSION

The average viral load of our patients in dialysis is lower than the levels usually observed in hepatitis C infected patients without end stage renal disease. The lower viral load in patients treated with peritoneal dialysis, and no history of hemodialysis, probably denotes lower risk of chronic liver disease in these subpopulation.

[Viral C hepatitis in patients with end stage renal disease. II. Viral genotypes]

BACKGROUND

The hepatitis C virus infection is highly prevalent in patients on chronic dialysis. There are more than 10 variants of the hepatitis C virus, with 55 to 72% of identity among them at the amino acid level. However, we do not know the specific genotype in dialysis patients in Mexico. Thus, the aim of the present study was to know the specific genotypes of the C virus in infected dialysis patients, to know the distribution of genotypes in the different dialysis techniques and to know the relation between genotype and hepatic disease stage.

METHODS

We performed a prospective, transversal and comparative study in patients in dialysis in three hospital centers in the south of Mexico City. The presence of C-type hepatitis infection was assessed by ELISA II and qualitative RT-PCR in blood samples. The genotype of the hepatitis C virus was determined by analysis of the restriction pattern of the RT-PCR product using Mva I, Hinf I, BstU I and ScrF I restriction enzymes. Variables analyzed were: age, gender, etiology of renal failure, kind and time in substitutive therapy, transfusion and hepatitis history, liver function test, blood urea, serum creatinine and blood cell count.

RESULTS

We studied 235 dialysis patients that were divided following their dialysis modality into: 132 in continue ambulatory peritoneal dialysis (CAPD), 17 in CAPD, but with history of hemodialysis (PD/HD) of at least one month and 86 on hemodialysis (HD). The hepatitis infection was detected in 24 of the 235 patients (CAPD = 4.5%, PD/HD = 41.1% and HD = 12.7%; p < 0.001). The most common genotype was 1B (12/24), followed by 1A and 2A (4/24 each one), and finally by 2B and 2C (2/24 each one). We detected no patients with genotypes 3 to 6. The patients with 2A genotype were older than those infected with 1A (p < 0.05). History of surgery, transfusions, and hepatitis was similar in all genotypes. Finally the time in dialysis was longer in patients with 2A genotype than others (2A = 60.5 +/- 71.5 months, vs. 1A = 11.5 +/- 11.3, 1B = 26 +/- 26.4 y 2B/C = 17.5 +/- 13.4), but the difference did not reach statistical significance. The genotype distribution between dialysis techniques showed that 1B genotype was the most frequent in all modalities. The 1A genotype was present in similar proportions in patients of the three dialysis groups, the 2C genotype was present only in patients with CAPD. Finally, the 2B was only found in hemodialysis patients.

DISCUSSION

The assessment of viral genotype revealed that 1B is the most common genotype in patients on chronic dialysis in Mexico City. The fact that the 1B and 1A genotypes were the most common types in our dialysis population suggest that transmission was similar to the general population, that is, probably by blood transfusions.

[Hepatitis C viral in patients with terminal chronic kidney failure. I. Prevalence]

BACKGROUND

The prevalence of hepatitis C in patients with end stage renal disease, under renal replacement therapy either with hemodialysis (HD) or continuous ambulatory peritoneal dialysis (CAPD), is higher than in the general population. The prevalence of hepatitis C in patients under dialysis, however, is unknown in Mexico. Thus, the major goals of the present study were to determine the prevalence of hepatitis C in our patients on dialysis, and the risk factors associated with it.

METHODS

We performed a cross-sectional and comparative study in patients under dialysis in three hospital centers in the south of Mexico City. For every patient we evaluated: age, gender, etiology of the renal failure, modality and time in dialysis, transfusion and surgical history, serum albumin, aminotranferases, BUN, and serum creatinine. The presence of hepatitis C was assessed by ELISA II and qualitative RT-PCR in blood samples. In all patients diagnosed as having hepatitis C, RT-PCR to amplified part of the virus genome was also carried out in the dialysis fluid.

RESULTS

We studied 235 dialysis patients that were classified according to their dialysis modality in: 132 patients under CAPD, 17 under CAPD and history of HD (PD/HD) and 86 under HD. The time under dialysis was different between the study groups: CAPD 29.6 +/- 22.3 months, PD/HD 39 +/- 42.3 and HD 14.2 +/- 15.6 (p < 0.01). The presence of hepatitis C was detected in 24 of the 235 patients, for a global prevalence of 10.2%. In no case was viral RNA found in the dialysis fluid. The prevalence varied, however, according to the type of dialysis. It was in the CAPD group 4.5%, 12.7% in the HD group, and 41.1% in the PD/HD group (p < 0.001). The multivariate analysis showed that the risk factors for hepatitis C are transfusions before the year of 1991 (Odds Ratio = 6.4), and history of hepatitis (OR = 4.3). Since less patients are seen with transfusions before 1991, we constructed another model in which this variable was excluded. This new multivariate model showed that history of surgery (OR = 4.4), the use of HD as the dialysis modality (OR = 3.5), and prolonged time under dialysis (OR = 1.01) were all significantly associated with the presence of hepatitis.

DISCUSSION

Our results show that the prevalence of hepatitis C is lower in our patients that the prevalence reported by many others (average of other countries 18.5%). Since we found a higher prevalence in HD than in CAPD, even with the lower time under dialysis in the HD group, it is possible that our lower overall prevalence is secondary to the fact that CAPD is the most frequent mode of dialysis in our country. We observed the highest prevalence in the PD/HD group, that is probably due to longer exposure to the risk factors. The association with transfusions before 1991 indicates that the infection was acquired in some patients before dialysis was started. Our results showed that the CAPD is the dialysis technique with lower risk of hepatitis C infection.

[Percutaneous kidney biopsy, analysis of 26 years: complication rate and risk factors; comment]

Percutaneous renal biopsy is an invasive procedure that can result in major and minor complications. The objective of this study was to know the frequency and type of complications in relation with this procedure, as well as the efficacy to obtain enough material for diagnosis.

METHODS

Retrospective study. We review the charts of patients to whom a percutaneous renal biopsy of native kidneys was done between January 1970 and March 1996. The following data were obtained: age, gender, clinical and histopathological diagnosis, complications associated with the procedure (minor: hematuria, local infections, hematoma; major: transfusions, severe infections, surgery, nephrectomy, arteriography, embolism and death).

RESULTS

We analyzed 1,005 renal biopsies in 840 patients, mean age 37.7 +/- 13.1 years, 67% female. There were no complications in 88.8% (893 biopsies), minor complications in 8.65% (87 biopsies) and only in 2.4% of the procedures major complications. We divided the cases in two groups: percutaneous renal biopsy without complications (n = 893, 89%) and with complications (n = 112, 11%). The most frequent complications were hematuria (91 cases, 9.1%) and perirenal hematoma (29 cases, 2.7%). In these cases transfusion was required in 2.4% (26). Infectious complications were: urosepsis in 7 cases (0.7%), bacteremia, sepsis and perirenal abscesses (1 case each, 0.1%). One patient died because of multiple complications (0.1%). We observed greater risk of major complications on patients in those who biopsy was done because of acute renal failure (OR 4.03, p < 0.003).

DISCUSSION

In our experience percutaneous renal biopsy is a low risk procedure. Most complications are minor and without clinical repercussion. There must be a strict selection criteria of the patients to whom percutaneous renal biopsy is going to be done because of the risk of severe complications.

[Continuous hemodialysis in the treatment of acute kidney failure]

INTRODUCTION

Continuous replacement therapy of renal function has gained acceptance over the last decade for the treatment of acute renal failure. In the present study we present our experience using continuous hemodialysis (CHD) in our institution.

PATIENTS AND METHODS

This is a prospective analysis of the CHD treated patients in the intensive care unit (ICU) of our institution over an 24-month period. CHD was performed through a double-lumen catheter such as Mahurkar. We have performed 28 CHD procedures in 28 patients, from which four were excluded from the analysis. Three patients were excluded as CHD lasted less than 12 hours and one patient because he had chronic renal failure. The studied variables were: heart and respiratory rate, mean arterial pressure, body temperature, APACHE II classification status, arterial gasometry, cell blood count, BUN, creatinine, serum electrolytes, and hepatic enzymes. We also registered urine output, diuretic use, and the mean dose of inotropic drugs employed per day. These variables were obtained at the admittance to the ICU, before the initiation of CHD and after 24 and 48 hours. We also registered age, gender, and final evolution.

RESULTS

We evaluated 24 patients with mean age of 58.1 +/- 17.5 years in which CHD was use for a mean time of 4.6 +/- 2.8 days. Total ultrafiltrate was 19.5 +/- 8.4 liters, for a mean of 4.2 liters per day. CHD resulted in improvement of heart and respiratory rate, mean arterial pressure and laboratory variables such as arterial pH, bicarbonate concentration, BUN and potassium. It also decreased significant by the use of inotropic drugs. Five out of twenty-four patients survived (20.8%). The survived patients had significant lower age than the died patients (39.2 +/- 20 years vs. 63 +/- 13.3; p < 0.001), lower time between the admittance to ICU and the beginning of CHD (1.4 +/- 0.5 days vs. 3.5 +/- 2.6; p < 0.01) and lower APACHE II classification at admittance to ICU (7.4 +/- 1.6 vs. 19.0 +/- 2.7; p < 0.001) and at the start of CHD (13.6 +/- 3.2 vs. 24.7 +/- 3.7; p < 0.001). However, multivariate analysis revealed that the only variable associated with a better survival was a lower time between the admittance to intensive care and the beginning of CHD.

DISCUSSION

CHD is a safe technique that can be used for acute renal failure patients who have contraindications for intermittent HD. This technique can be used in hospitals offering intermittent hemodialysis and intensive care. CHD use is associated with improvement of hemodynamic and metabolic alterations in patients with shock. Our data support the concept that the earlier the initiation of CHD the better the prognosis.

[Idiopathic ascites associated with hemodialysis. Case report and literature review]

BACKGROUND

Idiopathic dialysis ascites (IDA) is an uncommon disease characterized by the absence of a cause that can explain its presentation.

CASE REPORT

Thirty year old female, with diabetic nephropathy under chronic hemodialysis, with massive ascites. Treatment with intensive ultrafiltration was non-successful, and we had poor clinical results with consecutive paracentesis. The study of ascitic fluid was normal. We discarded cardiovascular, hepatic, infectious, neoplastic, and metabolic etiologies and laparoscopy with hepatic and peritoneal biopsies were non-diagnostic. Finally, after renal transplantation, a rapid decrease of the ascites was observed and the diagnosis of IDA was established.

DISCUSSION

IDA is a rare entity that does not seem to be related with uremia as it is usually present after the start of hemodialysis. Malnutrition and hypoproteinemia are frequently associated and could be part of the etiology of IDA, which explains the lack of response to ultrafiltration and salt restriction, usual treatment for ascites control. The pathophysiological explanation of the dramatic response of this patients to renal transplantation is unclear.