Follow-up of patients with epidemic poststreptococcal glomerulonephritis

Angiotensin II and post-streptococcal glomerulonephritis

BACKGROUND

Post-streptococcal glomerulonephritis (PSGN) is a consequence of the infection by group A beta-hemolytic streptococcus. During this infection, various immunological processes generated by streptococcal antigens are triggered, such as the induction of antibodies and immune complexes. This activation of the immune system involves both innate and acquired immunity. The immunological events that occur at the renal level lead to kidney damage with chronic renal failure as well as resolution of the pathological process (in most cases). Angiotensin II (Ang II) is a molecule with vasopressor and pro-inflammatory capacities, being an important factor in various inflammatory processes. During PSGN some events are defined that make Ang II conceivable as a molecule involved in the inflammatory processes during the disease.

CONCLUSION

This review is focused on defining which reported events would be related to the presence of this hormone in PSGN.

Evaluation of the significance of complement-related genes mutations in atypical postinfectious glomerulonephritis: a pilot study

BACKGROUND

Postinfectious glomerulonephritis with C3-dominant glomerular deposition (C3-PIGN) involves C3-dominant glomerular deposition without immunoglobulin. Atypical C3-PIGN involves persistent hypocomplementemia. We investigated the clinical features and explored complement-related gene mutations in atypical PIGN patients.

METHODS

We enrolled atypical C3-PIGN patients and collected data regarding the clinical presentation and pathological characteristics and follow-up data. We measured the levels of complement associated antibodies and performed whole-exome sequencing (WES) to detect mutations in complement-related genes.

RESULTS

The analysis included six atypical C3-PIGN patients. All patients were antistreptolysin-O (ASO) positive. All patients had varying degrees of hematuria, and four patients had proteinuria. None of the patients were positive for complement-related antibodies. All patients possessed mutations of genes related to the complement pathway, including alternative complement pathway genes-CFI, CFH, CFHR3, CFHR5; the lectin pathway gene-MASP2; and the common complement pathway gene-C8A. The rare variant of CFHR3 has been reported in C3 glomerulonephritis. During 56-73 months of follow-up, the levels of urine markers in three patients recovered within 6 months, and the remaining patients had abnormal urine test results over 12 months. Patients who received glucocorticoid therapy recovered faster.

CONCLUSIONS

Our study suggested that complement-related gene mutations may be an important cause of persistent hypocomplementemia in atypical C3-PIGN patients. In addition to variations in alternate pathway-related genes, we also found variations in lectin pathway-related genes, especially MASP2 genes. Although the overall prognosis was good, atypical C3-PIGN patients exhibited a longer period for recovery. Our results suggested that atypical C3-PIGN patients should receive more medical attention and need testing for mutations in complement-related genes.

Twenty-year Follow-up of Patients With Epidemic Glomerulonephritis due to Streptococcus zooepidemicus in Brazil

Introduction

Post-streptococcal glomerulonephritis (PSGN) has a good prognosis in children, but few studies have evaluated the long-term renal outcomes in adults with PSGN.

Methods

In a follow-up study, 47 predominantly adult patients with PSGN due to group C Streptococcus zooepidemicus were reassessed 20 years after an outbreak in Nova Serrana, Brazil. We evaluated clinical characteristics, renal outcomes, and the trajectory of the estimated glomerular filtration rate (eGFR) by the creatinine-based chronic kidney disease-epidemiology collaboration equation from 5 follow-up assessments. Logistic regression and mixed-effects regression were used in the analysis.

Results

After 20 years, the participants’ mean age was 56.6±15.1 years. Thirty-four (72%) patients had hypertension, 21 (44.7%) had eGFR <60 ml/min per 1.73 m², 8 of 43 (18.6%) had urine protein-to-creatinine ratio >150 mg/g, and 25 (53%) had CKD (low eGFR and/or increased proteinuria). Increasing age was associated with CKD (odds ratio: 1.07; 95% confidence interval [CI]: 1.02–1.13; P = 0.011) in multivariate analysis. The mean eGFR decline in the last 11 years of follow-up was −3.2 ml/min per 1.73 m² per year (95% CI: −3.7 to −2.7). Older age at baseline (coefficient −1.05 ml/min per 1.73 m² per year; 95% CI −1.28 to −0.81; P < 0.001), and hypertension 5 years after the outbreak (coefficient −7.78 ml/min/1.73 m²; 95% CI −14.67 to −0.78; P = 0.027) were associated with lower eGFR during the whole study period.

Conclusion

There was a marked worsening of renal function and a high prevalence of CKD and hypertension after 20 years of PSGN outbreak. Long-term follow-up is warranted after PSGN, especially among older patients.

A Comprehensive Review Study on Glomerulonephritis Associated With Post-streptococcal Infection

Post-streptococcal glomerulonephritis (PSGN) is an immune-complex mediated inflammation that used to be considered one of the commonest causes of acute nephritis amongst children. PSGN is characterized by the proliferation of cellular elements called nephritogenic M type as a result of an immunologic mechanism following an infection of the skin (impetigo) or throat (pharyngitis) caused by nephritogenic strains of group A beta-hemolytic streptococci, a gram-positive bacteria that enters the body across pores in the skin or mucus epithelia and is responsible for more than 500,000 deaths annually due to multiple subsequence diseases such as rheumatic heart disease, rheumatic fever, PSGN, and other invasive infections. After the infection, the formation of an immune complex of antigen-antibody and complement system will take place and will deposit in the glomeruli where the injury occurs and leads to inflammation. The manifestations of PSGN can be explained by nephritic syndrome manifestation. PSGN is diagnosed by laboratory tests like microscopy and urinalysis. The imaging studies in PSGN could be used to assess the possible complications of PSGN such as pulmonary congestion and chronic kidney disease. The management of PSGN is symptomatic. If PSGN is not treated, the patient may develop chronic kidney disease. The main way to prevent PSGN is to treat group A streptococcal (GAS) infections by giving good coverage of antibiotic therapy to a patient who has primary GAS infections to prevent the development of the complication.

Infections Caused by Group C and G Streptococcus (Streptococcus dysgalactiae subsp. equisimilis and Others): Epidemiological and Clinical Aspects

Streptococci carrying serogroup C and G antigens, and in particular, Streptococcus dysgalactiae subsp. equisimilis (SDSE), are emerging human pathogens that are increasingly isolated from patients with a myriad of infections that range from mundane to life-threatening. SDSE is microbiologically similar to Streptococcus pyogenes. These streptococci frequently cause infections of the throat and skin and soft tissues. Moreover, they may invade the bloodstream and disseminate widely to many deep tissue sites, including the endocardium. Life-threatening invasive infections due to SDSE, including the streptococcal toxic shock syndrome, occur most frequently in patients with severe underlying medical diseases. Treatment with penicillin is adequate under most circumstances, but treatment failure occurs. SDSE may also be resistant to other antibiotic classes including tetracyclines, macrolides, and clindamycin. Most human infections caused by groups C and G streptococci are transmitted from person to person, but infections due to Streptococcus equi subsp. zooepidemicus (and, rarely, to S. equi subsp. equi) are zoonoses. Transmission of these latter species occurs by animal contact or by contamination of food products and has been associated with the development of poststreptococcal glomerulonephritis. Members of the Streptococcus anginosus group, usually classified with the viridans group of streptococci, are associated with a variety of pyogenic infections.

[Acute glomerulonephritis in the 21-st century]

The paper discusses the specific features of the current course of acute glomerulonephritis, the spectrum of its etiological factors, and clinical manifestations. The factors influencing the course and outcomes of acute glomerulonephritis, including the risk of its progression to chronic kidney disease, are specially depicted.

Ten-Year Follow-up of Patients with Epidemic Post Infectious Glomerulonephritis

Background

Scarce information on outcomes of epidemic post infectious glomerulonephritis is available. This is a 10-year follow-up of the patients that developed acute glomerulonephritis in an epidemic outbreak caused by group C Streptococcus zooepidemicus in Brazil in 1998, that were also previously evaluated 2 and 5 years after the acute episode.

Methods

In this prospective study 60 cases (out of 134 in 1998) were reevaluated after 10 years, as well as community controls matched by gender and age. They underwent clinical and renal function evaluation, including serum creatinine and cystatin C, estimated glomerular filtration rate (eGFR), albuminuria and hematuria.

Results

Comparisons of clinical and renal function aspects of 60 patients and 48 community controls have not shown significant differences (eGFR <60 ml/min/1.73m² and/or albuminuria >30mg/g creatinine: 13.8% vs. 12.2%, respectively, p = 0.817) except for a higher frequency of hypertension in the cases (45.0% vs. 20.8%, p = 0.009). Comparing the same patients affected in the acute episode, 2, 5 and 10 years later, it was observed an improvement of median eGFR levels at 2 years and a trend toward subsequent stabilization in these levels, associated with decrease in albuminuria and increased hypertension rates in the last survey. At 10 years it was not observed additional reduction of renal function using serum creatinine, eGFR and cystatin C.

Conclusions

During the acute episode of epidemic GN a considerable proportion of patients presented hypertension and reduced renal function; after 2 years and particularly at this 10-year follow-up survey there was no worsening of renal function parameters, except for persistent higher frequency of hypertension. Nevertheless, a longer follow up is necessary to confirm that progressive loss of renal function will not occur.

An overview on frequency of renal biopsy diagnosis in Brazil: clinical and pathological patterns based on 9,617 native kidney biopsies

BACKGROUND

Studies about the prevalence of renal and particularly glomerular diseases in Brazil are still scarce.

METHODS

We evaluated retrospectively the reports of 9,617 renal biopsies, analyzed by the same pathologist, from January 1993 to December 2007.

RESULTS

The 9,617 renal biopsies performed in subjects of all ages in native kidneys. 4,619 were primary glomerulopathies (GN), the most frequent was focal segmental glomerulosclerosis (FSGS, 24.6%), followed by membranous nephropathy (MN, 20.7%), IgA nephropathy (IgAN, 20.1%), minimal change disease (MCD, 15.5%), mesangioproliferative non IgAN (nonIgAN, 5.2%), diffuse proliferative GN (DPGN, 4.7%) and membranoproliferative GN (MPGN, 4.2%). Lupus nephritis was responsible for most cases which etiology was determined, i.e., 950 out of 2,046 cases (45.5%), followed by post infectious GN (18.9%), diabetic nephropathy (8.5%), benign and malignant nephroangiosclerosis (7.3%), haemolytic-uraemic syndrome and thrombotic thrombocytopenic purpura (HUS/TTP), amyloidosis (4.8%) and vasculitis (4.7%). There was a predominance of secondary GN in the North, mostly due to lupus nephritis (LN); FSGS was very common in Northeast (27.7%), Central (26.9%) and Southeast regions (24.1%); IgAN was most frequent in South (22.8%) and MN in North (29.6%); the total prevalence of MPGN was low, and its regional distribution has not changed along the years.

CONCLUSION

FSGS was the most frequent primary glomerular disease, followed closely by MN and IgAN. The predominance of FSGS is in accordance with recent studies all over the world that revealed its frequency is increasing. Lupus nephritis predominated among secondary GN in most regions, a finding observed in other studies.

Changing epidemiology of acute post-streptococcal glomerulonephritis in Northeast Florida: a comparative study

The objective of this study was to review the epidemiological patterns of acute post-streptococcal glomerulonephritis (APSGN) in a pediatric population. We compared incidence, pathogenesis, clinical presentation and outcomes in two APSGN pediatric patient cohorts in northeastern Florida. Retrospective medical records were reviewed of children who were admitted to our institution with a diagnosis of APSGN. Patients admitted between 1999 and 2006 (recent cohort) were compared with a previously reported cohort of patients admitted between 1957 and 1973 (earlier cohort). The recent cohort comprised 45 children with APSGN of whom 87% were male and 13% were female; the median age was 7 years, and there was an average incidence of 6.4 patients per year. The earlier cohort comprised 153 children with APSGN of whom 62% were male and 38% were female; the median age 4.25 years, and there was an average incidence of 10.9 patients per year. The recent cohort was predominantly White-American (62%) and the earlier cohort predominately African American (87%). In the recent cohort, 64% of patients had antecedent pharyngitis, and in the earlier cohort, 66% of patients had antecedent pyoderma. In the recent cohort, 11% of APSGN cases occurred between August to October, and in the earlier cohort, 50% occurred during these months. In the recent cohort, symptoms of APSGN at presentation were milder and all cases recovered, but in the earlier cohort two deaths (1.3% mortality) were reported. In conclusion, there has been a decline in the incidence and severity of APSGN at our institute in recent decades. Pharyngitis has replaced impetigo as the predominant cause of APSGN. The etiological agent for impetigo has changed over the last decade, which has impacted the incidence, racial distribution, seasonal variation and severity of APSGN.

Co-occurrence of poststreptococcal reactive arthritis and acute glomerulonephritis

We report a 16-year-old patient who developed concurrent poststreptococcal reactive arthritis and acute glomerulonephritis. A high titer of antistreptolysin O antibody confirmed the preceding streptococcal infection. The patient presented with symmetric persistent tenosynovitis of hands and feet. Renal biopsy showed typical findings of acute glomerulonephritis with crescent formation. Physicians who treat patients with arthritis of acute onset, especially after throat infection, should be aware of possible urinary abnormalities or renal dysfunction.

Post-streptococcal glomerulonephritis in Sydney: a 16-year retrospective review

AIM

Post-streptococcal glomerulonephritis (PSGN) is a frequent cause of acute nephritis in children. Numerous studies have described PSGN in high-risk populations yet few data describing PSGN in a low-incidence population exist. This study aimed to describe the epidemiology, clinical manifestations, diagnosis, complications and outcomes of PSGN in an urban Australian population.

METHODS

A 16-year retrospective review of case notes and laboratory data was conducted at a tertiary Sydney paediatric hospital.

RESULTS

Thirty-seven children were treated for PSGN with a mean age of 8.1 years (range 2.6-14.1 years). Twenty-eight subjects (75.7%) had a history of a recent upper respiratory tract or skin infection. Hypertension and/or oedema was present in 29 subjects (78.4%). Streptococcal pharyngitis was identified as the likely source in 17 subjects (45.9%). Skin infections occurred less frequently. Antibodies against streptolysin O, streptokinase or deoxyribonuclease B were elevated when a single titre was measured in 35 subjects (94.6%). Thirty subjects (81.1%) developed renal impairment (median peak creatinine, 95 micromol/L, range 39-880 micromol/L). No correlation was demonstrated between peak creatinine, age, ethnicity, streptococcal titres and serum complement levels. The mean length of admission was 8.2 days. Seven subjects (18.9%) had a complicated course with three subjects requiring dialysis. Only one subject has ongoing renal dysfunction.

CONCLUSION

Significant differences are seen in a low-incidence urban Australian population with PSGN when compared with endemic or epidemic disease in high-risk populations. The higher rates of complications that were seen compared with previously studied populations need further clarification.

Outbreak of Streptococcus equi subsp. zooepidemicus infections on the island of Gran Canaria associated with the consumption of inadequately pasteurized cheese

Streptococcus equi subsp. zooepidemicus infections are infrequent in humans. A clinical and epidemiological study of a milk-borne outbreak caused by this organism is described. Fifteen patients (5 females, 10 males) with a median age of 70 years (range 47-86) were infected. Twelve (80%) had underlying diseases. Infection with S. equi subsp. zooepidemicus presented as primary bacteremia in six cases, as bacteremia associated with aortic aneurism in four cases, as septic arthritis in two cases, as pneumonia in two cases, and as meningitis in one case. Five (33.3%) patients died. A case-control study proved that consumption of inadequately pasteurized cheese of a specific brand was associated with S. equi subsp. zooepidemicus disease (OR=4.5; 95% CI 1.57-19.27; p<0.001). This outbreak serves as a reminder that S. equi subsp. zooepidemicus causes serious infections that are usually zoonoses. Identification of beta-hemolytic streptococci to the species level to detect contaminated foods of animal origin is important for preventing new food-borne outbreaks. For a precise characterization of the isolates, the application of molecular markers is recommended.

End-stage renal disease in Brazil: Epidemiology, prevention, and treatment

Brazil is one of the largest and most populous nations in the world, ranking among the 5 largest economies in the Americas and among the 15 largest economies in the world. However, Brazil is still plagued by social problems such as the persistence of poverty and immense deficiencies in its health system. Currently, there are approximately 390 patients on chronic renal replacement therapy (RRT) per million population, about one third the US prevalence, which suggests that end-stage renal disease is either underdiagnosed or undertreated. The epidemiology of renal disease in the small remaining native Brazilian population is largely unknown. However, it is likely that the prevalence of renal disease is low among at least 2 tribes: the Yanomamis in northern Brazil and the Xingu Indians in central Brazil. Sodium intake is very low, physical activity is intense, and the prevalence of hypertension and cardiovascular disease is negligible among these people, which stresses the potential pathogenic importance of so-called civilized habits. There is currently no conclusive evidence that African descendants or any other Brazilian ethnic minorities are especially vulnerable to renal disease. Access to RRT in Brazil is universal. However, because both the end-stage renal disease population and operational RRT costs are steadily increasing, the system may face severe limitations in the near future. Much effort is needed to limit the prevalence of renal disease, to detain or retard the progression of chronic nephropathies, and to ensure that high-quality RRT will remain available to all those who need it.

Epidemic glomerulonephritis due to Streptococcus zooepidemicus in Nova Serrana, Brazil

BACKGROUND

In 1998, there was a large outbreak of acute glomerulonephritis in Nova Serrana, Brazil, caused by group C Streptococcus zooepidemicus. This article reviews the characteristics of the outbreak and some aspects of the patients' follow-up.

METHODS

We describe clinical characteristics of patients with acute nephritis. Using case-control studies, we identified the source of infection. Cultures of oropharyngeal swabs from patients were performed. Of 135 patients identified in 1998, available patients were reexamined in a prospective study after 2 and 5 years.

RESULTS

Lancefield group C S. zooepidemicus was identified as the causative organism and linked to the consumption of cheese produced from unpasteurized milk. Of the original group of 134 patients, 4 died in the acute phase and 5 (3.7%) required chronic dialysis. After 2 years, of the 69 cases reevaluated, 94% were adults (mean +/- standard error age: 39 +/- 2 years); we found arterial hypertension in 42% (N= 27/64) of the patients, reduced creatinine clearance (<80 mL/min/1.73 m(2)) in 30% (N= 20/67), and increased microalbuminuria (>20 microg/min) in 34% (N= 22/65). Preliminary data at 5-year follow-up suggest that the percentage of patients with creatinine clearance lower than 60 mL/min increased from 9% to 15%.

CONCLUSION

This article highlights the dangers of consuming unpasteurized dairy products. Follow-up of patients with epidemic poststreptococcal glomerulonephritis due to S. zooepidemicus show that a considerable proportion present hypertension, reduced renal function, and increased microalbuminuria.

Akutes rheumatisches Fieber (ARF) und Poststreptokokken reaktive Arthritis (PSRA)—

Betahemolytic strains of streptococcus A are able to induce a spectrum of immunologically induced diseases, depending on the immunogenic M structure of the bacteria as well as on the genetic determined reaction of the host. In acute rheumatic fever (ARF) the Jones criteria, revised and modified several times and updated in 1992, remain the diagnostic standard. Echocardiography, still not included in the Jones criteria, has become a very important diagnostic tool, especially as half of the ARF induced carditis cases are clinically inapparent. Diagnosis may be very difficult if arthritis is the only major sign, especially if not occurring in the typical migrating pattern, a fact frequently reported from countries with a high risk of ARF. Poststreptococcal reactive arthritis (PSRA) has been described as a different entity as well as a part of rheumatic fever. There is a lack of validated diagnostic criteria to establish a reliable diagnosis. There are no accepted recommendations for antibiotic prophylaxis in PSRA.

The Role of Nutrition in Chronic Renal Insufficiency of Childhood: How Much Do We Know?

Dietary protein restriction in the treatment of symptomatic renal failure has been utilized for many years, especially as a means for reduction of 'fixed acid" load. Studies in animal models of renal failure suggest that low protein intake may retard the progression of renal disease as well. However, large, well-organized investigations into this question in humans have fallen prey to difficulties that are almost impossible to overcome. Chief among these difficulties is the problem of chronically reducing protein intake in patients with a lifelong intake far above the recommended daily allowance (RDA). Another is the fact that all previous studies have been performed in patients with moderate to severe compromise of renal function. Thus, the potential efficacy of reduced protein intake in the retardation of the progression of renal disease remains an open question. In this article, we discuss the current state of knowledge and propose an approach to answering this question.

Five-year follow-up of patients with epidemic glomerulonephritis due to Streptococcus zooepidemicus

BACKGROUND

In 1998 there was a large outbreak of acute glomerulonephritis in Nova Serrana, Brazil, caused by group C Streptococcus zooepidemicus. This study describes the follow-up of these patients, after a mean time of 5.4 years of the acute episode.

METHODS

Of 135 cases identified in 1998, 56 were re-examined in a prospective study and had measurements of blood pressure, creatinine clearance (estimated by the Cockcroft and Gault formula), microalbuminuria (radioimmunoassay), urine sediment analysis and a protein dipstick test.

RESULTS

Of the original group of 135 subjects, 3 died in the acute phase and 5 (3.7%) required chronic dialysis. Of the 56 cases re-evaluated, 54 (96%) were adults (mean+/-SD age, 43+/-17 years) and 36 (64%) females. At the follow-up examination, we found arterial hypertension in 30% (n = 17/56) of the subjects, reduced creatinine clearance (<80 ml/min) in 49% (n = 26/53) and increased microalbuminuria (>20 microg/min) in 22% (n = 11/51). Compared to the evaluation carried out 3 years before, the number of cases with creatinine clearance lower than 80 ml/min increased from 20 to 26 (of 53 cases). Increased microalbuminuria and/or reduced creatinine clearance were detected in 57% (n = 32/56) of the subjects. Patients with reduced creatinine clearance were older than those without reduced renal function (54+/-15 vs 34+/-12 years, P<0.001).

CONCLUSIONS

After a mean time of 5.4 years, a relatively high proportion of patients with epidemic poststreptococcal glomerulonephritis due to S.zooepidemicus present hypertension, reduced renal function and increased microalbuminuria.

[Evaluation of two rapid tests for the determination of microalbuminuria and the urinary albumin/creatinine ratio]

OBJECTIVE

Microalbuminuria screening is justified on the grounds of its cost-benefit ratio in patients at risk of kidney damage while the process is still reversible. The aim of the present study was to evaluate the DCA 2000 analyser and the Clinitek 50 system (Bayer), which simultaneously measure urinary albumin and creatinine levels to adopt them as rapid methods for microalbuminuria detection.

METHODS

One hundred twenty-seven urine samples from pediatric patients with various disorders were assessed. Albumin, creatinine, and the albumin/creatinine ratio were determined using the DCA 2000 analyzer and the Clinitek 50 system, which were compared against the usual reference laboratory methods.

RESULTS

The correlation coefficient of nephelometric values vs the DCA 2000 analyzer was 0.914 for albumin, 0.970 for creatinine and 0.839 for the albumin/creatinine ratio. At an albumin cut-off concentration of 30 mg/l, the sensitivity, specificity, positive predictive value and negative predictive value were 100 %, 93 %, 84 % and 100 % for the DCA 2000 analyzer and 91.7 %, 86 %, 55 % and 98 % for the Clinitek 50 system. ROC curve analysis showed that the DCA 2000 system was more effective than the Clinitek 50 in microalbuminuria screening.

CONCLUSIONS

The data obtained with the DCA 2000 system showed close agreement with those obtained with reference laboratory methods. The immediate availability of results is a great advantage in clinical practice. The Clinitek-Microalbumin dipstick system is a semiquantitative method that is easy to use, low in cost, simple and useful for screening, but it is less reliable as a follow-up method.

Nephrology in Latin America, with special emphasis on Brazil

Latin America constitutes a complex universe that shows extreme variation regarding socioeconomic and human development. Brazil is the largest and most populous Latin American country, and combines characteristics encountered in developed countries with problems typically associated with the poorest regions of the world. These disparities condition the profile of renal disease in Brazil, with glomerulonephritis still the leading cause of ESRD. Little is known about the epidemiology of renal disease in the Brazilian (or Latin American) native population, which is numerous in some Central and South American countries, but constitute a very small minority in Brazil. However, interesting information has been obtained from the Yanomamis, a tribe living in Northern Brazil and Southern Venezuela. Hypertension is virtually absent among these people, who ingest very little sodium, lending strong support to the concept that sodium retention, a "civilization" factor, plays a role in the pathogenesis of arterial hypertension. Despite Brazil's striking socioeconomic disparities, access to RRT is in principle accessible to all those in need of it. The dialysis units have been modernized in recent years, whereas the Government covers most expenses related to RRT. However, the prevalence of RRT in Brazil is currently approximately 320 per million population, less than one third as high as in the US, suggesting that ESRD may be underdiagnosed in the country. Much effort is still needed to limit the prevalence of renal disease and to improve the quality and the reach of RRT in Brazil and in Latin America.