Real-world evidence on the dosing and safety of C.E.R.A. in pediatric dialysis patients: findings from the International Pediatric Dialysis Network registries.

BACKGROUND: This retrospective real-world study used data from two registries, International Pediatric Peritoneal Dialysis Network (IPPN) and International Pediatric Hemodialysis Network (IPHN), to characterize the efficacy and safety of continuous erythropoietin receptor activator (C.E.R.A.) in pediatric patients with chronic kidney disease (CKD) on peritoneal dialysis (PD) or hemodialysis (HD). METHODS: IPPN and IPHN collect prospective data (baseline and every 6 months) from pediatric PD and HD centers worldwide. Demographics, clinical characteristics, dialysis information, treatment, laboratory parameters, number and causes of hospitalization events, and deaths were extracted for patients on C.E.R.A. treatment (IPPN: 2007-2021; IPHN: 2013-2021). RESULTS: We analyzed 177 patients on PD (median age 10.6 years) and 52 patients on HD (median age 14.1 years) who had ≥ 1 observation while being treated with C.E.R.A. The median (interquartile range [IQR]) observation time under C.E.R.A. exposure was 6 (0-12.5) and 12 (0-18) months, respectively. Hemoglobin concentrations were stable over time; respective means (standard deviation) at last observation were 10.9 (1.7) g/dL and 10.4 (1.7) g/dL. Respective median (IQR) monthly C.E.R.A. doses at last observation were 3.5 (2.3-5.1) µg/kg, or 95 (62-145) µg/m2 and 2.1 (1.2-3.4) µg/kg, or 63 (40-98) µg/m2. Non-elective hospitalizations occurred in 102 (58%) PD and 32 (62%) HD patients. Seven deaths occurred (19.8 deaths per 1000 observation years). CONCLUSIONS: C.E.R.A. was associated with efficient maintenance of hemoglobin concentrations in pediatric patients with CKD on dialysis, and appeared to have a favorable safety profile. The current analysis revealed no safety signals.

Hemolytic uremic syndrome associated with Shiga toxin-producing Escherichia coli infection in Argentina: update of serotypes and genotypes and their relationship with severity of the disease.

BACKGROUND: Shiga toxin-producing Escherichia coli (STEC) infection is the most common cause of hemolytic uremic syndrome (HUS). Only few studies correlated serotypes and stx genotypes with disease severity. This study aimed to update STEC serotypes, stx genotypes, and virulence factors (eae and ehxA) in a cohort of patients with STEC-HUS and investigate whether they influence the severity of disease. METHODS: In this multicentric study, children hospitalized between 2005 and 2016 with STEC-HUS confirmed by the National Reference Laboratory were included. Serotypes (O157, O145, O121, and others), stx genotypes (stx1a, stx2a, stx2c, stx2d, and others), and virulence factors were analyzed, and their association with dialysis requirement (>10 days); severe neurological, cardiovascular, and/or bowel involvement; and death was assessed. RESULTS: The records of 280 patients were reviewed; 160 females, median age 21 months (IQR18m). STEC O157 was isolated in 206 (73.6%) patients, O145 in 47 (16.8%), O121 in 15 (5.4%), and other serotypes in 12 (4.2%). The stx2a/2c genotype was carried by 179 (63.9%) strains, stx2a by 94 (33.6%), stx1a/stx2a by five (1.8%), and stx1a only by two (0.7%). All strains except six harbored eae and ehxA genes. Fifty-nine (21.1%) patients had severe neurological involvement, 29 (10.4%) severe bowel injury, 14 (5%) cardiovascular involvement, 53 (18.9%) required > 10 days of dialysis, and 12 (4.3%) died. Neither serotypes nor stx genotypes detected were significantly linked to severity. CONCLUSIONS: Serotype O157 and virulence stx2a/2c, eae, ehxA genotype are prevalent in Argentina, and no relationship was found between severity and serotypes and genotypes of STEC detected.

Acute peritoneal dialysis, complications and outcomes in 389 children with STEC-HUS: a multicenter experience.

BACKGROUND: Management of acute kidney injury (AKI) in children with hemolytic uremic syndrome induced by a Shiga toxin-producing Escherichia coli infection (STEC-HUS) is supportive; however, 40 to 60% of cases need kidney replacement therapy (KRT). The aim of this study was to analyze procedure complications, especially peritonitis, and clinical outcomes in children with AKI secondary to STEC-HUS treated with acute PD. METHODS: This is a multicenter retrospective study conducted among thirty-seven Argentinian centers. We reviewed medical records of 389 children with STEC-HUS hospitalized between January 2015 and February 2019 that required PD. RESULTS: Complications associated with PD were catheter malfunction (n = 93, 24%), peritonitis (n = 75, 19%), fluid leaks (n = 45, 11.5%), bleeding events (n = 23, 6%), and hyperglycemia (n = 8, 2%). In the multivariate analysis, the use of antibiotic prophylaxis was independently associated with a decreased risk of peritonitis (hazard ratio 0.49, IC 95% 0.29-0.81; p = 0.001), and open-surgery catheter insertion was independently associated with a higher risk (hazard ratio 2.8, IC 95% 1.21-6.82; p = 0.001). Discontinuation of PD due to peritonitis, severe leak, or mechanical complications occurred in 3.8% of patients. No patient needed to be transitioned to other modality of KRT due to inefficacy of the technique. Mortality during the acute phase occurred in 2.8% patients due to extrarenal complications (neurological and cardiac involvement), not related to PD. CONCLUSIONS: Acute PD was a safe and effective method to manage AKI in children with STEC-HUS. Prophylactic antibiotics prior to insertion of the PD catheter should be considered to decrease the incidence of peritonitis.

"Removal of nitrate and nitrite by hemodialysis in end-stage renal disease and by sustained low-efficiency dialysis in acute kidney injury".

BACKGROUND & PURPOSE: It is well established that end-stage renal disease (ESRD) is associated with increased cardiovascular morbidity and mortality both in the adult and pediatric population. Although the underlying molecular mechanisms are poorly understood, compromised nitric oxide (NO) bioactivity has been suggested as a contributing factor. With this in mind, we investigated the effects of hemodialysis on NO homeostasis and bioactivity in blood. METHODS & RESULTS: Plasma and dialysate samples were obtained before and after hemodialysis sessions from adults (n = 33) and pediatric patients (n = 10) with ESRD on chronic renal replacement therapy, and from critically ill adults with acute kidney injury (n = 12) at their first sustained low-efficiency dialysis session. Levels of nitrate, nitrite, cyclic guanosine monophosphate (cGMP) and amino acids relevant for NO homeostasis were analyzed. We consistently found that nitrate and cGMP levels in plasma were significantly reduced after hemodialysis, whereas post-dialysis nitrite and amino acids coupled to NO synthase activity (i.e., arginine and citrulline) were only significantly reduced in adults with ESRD. The amount of excreted nitrate and nitrite during dialysis were similar to daily endogenous levels that would be expected from endothelial NO synthase activity. CONCLUSIONS: Our results show that hemodialysis significantly reduces circulating levels of nitrate and cGMP, indicating that this medical procedure may impair NO synthesis and potentially NO signaling pathways.

Health-related quality of life among siblings of kidney transplant recipients.

Studies are increasingly recognizing health-related quality of life (HRQOL) as a key pediatric outcome in both clinical and research settings and an essential health outcome measure to assess the effectiveness of medical treatment. However, it has not yet been studied among the healthy siblings of kidney transplant recipients. The aim of this study, therefore, is to examine HRQOL among this population. We asked the following three groups to complete a validated measure of HRQOL among children (KIDSCREEN-52): siblings of children who had received kidney transplants (n = 50), kidney transplant recipients (n = 43), and a healthy control group (n = 84). We found that siblings of kidney transplant patients exhibited lower scores for financial resources and autonomy than kidney transplant recipients. They also served lower on physical well-being, financial resources, autonomy, and parent relations/home life than the control group. However, they scored higher on social acceptance than kidney transplant recipients. Our study underscores the importance of assessing HRQOL in families including a child diagnosed with a chronic illness. Siblings require social and psychological support to promote coping and adaptation.

Colostomy in children on chronic peritoneal dialysis.

BACKGROUND: This study aimed to evaluate outcome of children on chronic peritoneal dialysis (PD) with a concurrent colostomy. METHODS: Patients were identified through the International Pediatric Peritoneal Dialysis Network (IPPN) registry. Matched controls were randomly selected from the registry. Data were collected through the IPPN database and a survey disseminated to all participating sites. RESULTS: Fifteen centers reported 20 children who received chronic PD with a co-existing colostomy. The most common cause of end stage kidney disease was congenital anomalies of the kidney and urinary tract (n = 16, 80%). The main reason for colostomy placement was anorectal malformation (n = 13, 65%). The median age at colostomy creation and PD catheter (PDC) insertion were 0.1 (IQR, 0-2.2) and 2.8 (IQR 0.2-18.8) months, respectively. The colostomies and PDCs were present together for a median 18 (IQR, 4.9-35.8) months. The median age at PDC placement in 46 controls was 3.4 (IQR, 0.2-7.4) months of age. Fourteen patients (70%) developed 39 episodes of peritonitis. The annualized peritonitis rate was significantly higher in the colostomy group (1.13 vs. 0.70 episodes per patient year; p = 0.02). Predominant causative microorganisms were Staphylococcus aureus (15%) and Pseudomonas aeruginosa (13%). There were 12 exit site infection (ESI) episodes reported exclusively in colostomy patients. Seven colostomy children (35%) died during their course of PD, in two cases due to peritonitis. CONCLUSION: Although feasible in children with a colostomy, chronic PD is associated with an increased risk of peritonitis and mortality. Continued efforts to reduce infection risk for this complex patient population are essential.

Hyponatremia: a new predictor of mortality in patients with Shiga toxin-producing Escherichia coli hemolytic uremic syndrome.

OBJECTIVES: (1) Evaluate mortality rate in patients with Shiga toxin-producing Escherichia coli hemolytic uremic syndrome, (2) determine the leading causes of death, and (3) identify predictors of mortality at hospital admission. METHODS: We conducted a multicentric, observational, retrospective, cross-sectional study. It included patients under 18 years old with Shiga toxin-producing Escherichia coli hemolytic uremic syndrome hospitalized between January 2005 and June 2016. Clinical and laboratory data were obtained from the Argentine National Epidemiological Surveillance System of Hemolytic Uremic Syndrome. Clinical and laboratory variables were compared between deceased and non-deceased patients. Univariate and multivariate analyses were performed. ROC curves and area under the curve were obtained. RESULTS: Seventeen (3.65%) out of the 466 patients died, being central nervous system involvement the main cause of death. Predictors of death were central nervous system involvement, the number of days since the beginning of diarrhea to hospitalization, hyponatremia, high hemoglobin, high leukocyte counts, and low bicarbonate concentration on admission. In the multivariate analysis, central nervous system involvement, sodium concentration, and hemoglobin were independent predictors. The best cut off for sodium was ≤ 128 meq/l and for hemoglobin ≥ 10.8 g/dl. CONCLUSIONS: Mortality was low in children with Shiga toxin-producing Escherichia coli hemolytic uremic syndrome, being central nervous system involvement the main cause of death. The best mortality predictors found were central nervous system involvement, hemoglobin, and sodium concentration. Hyponatremia may be a new Shiga toxin-producing Escherichia coli hemolytic uremic syndrome mortality predictor.

Influence of CYP3A5 polymorphism on tacrolimus maintenance doses and serum levels after renal transplantation: age dependency and pharmacological interaction with steroids.

TAC, MMF and MP are used in pediatric kidney tx. The cytochrome P450 (CYP)3A5 enzyme appears to play a role in TAC metabolism. The aims of this study were to investigate CYP3A5 polymorphism's effect on TAC dosing and the age dependency of TAC dosing by testing blood concentrations, and the interaction between steroids and TAC during the first year after tx. Genomic DNA was extracted and amplified with specific primers. CYP3A5 alleles were confirmed by direct sequencing of PCR products on an automated AB13100 capillary sequencer. We studied 48 renal transplant patients (age at tx 12±0.5yr, 22 boys) receiving TAC, MMF, MP. Of these, 79% were CYP3A5*3/*3 (non-expressers homozygotes) and 21% were CYP3A5*1/*3 (expressers). TAC trough levels were 7.1±0.4ng/mL in CYP3A5*3/*3 patients and 6.5±0.7ng/mL in CYP3A5*1/*3 group (p=0.03). CYP3A5*1/*3 patients had lower levels of dose-adjusted TAC (36.7±5.8ng/mL/mg/kg/day) to achieve target blood concentration and required higher daily dose per weight (0.21±0.03mg/kg/day) than CYP3A5*3/*3 patients, 72.4±8.0ng/mL/mg/kg/day and 0.13±0.01mg/kg/day (p<0.001). Prepubertal patients with different CYP3A5 polymorphisms required significant higher TAC doses and achieved lower dose-normalized concentration compared with pubertal patients. Both TAC dose and adjusted-dose correlated with daily MP dose in CYP3A5*1*3 (r: 0.4, p<0.03 and r: 0.4, p<0.03) and in CYP3A5*3*3 (r: 0.6, p<0.01 and r: 0.47, p<0.001) patients. CYP3A5 polymorphism performed before tx could contribute to a better individualization of TAC therapy. The higher TAC dose in prepubertal patients and the pharmacological interactions between MP and TAC may not be fully explained by different CYP3A5 polymorphisms.

Quality of life among siblings of patients with chronic conditions. / Calidad de vida de los hermanos de pacientes con enfermedad crónica.

INTRODUCTION: Health-related quality of life (HRQoL) is a measure of health outcomes. It assesses the subjective and overall impact of diseases on daily life. It also provides multidimensional data about physical wellbeing, family and peers relations. HRQoL studies on siblings are limited. OBJECTIVE: To compare HRQoL among siblings of pediatric patients with chronic rheumatic diseases, kidney or liver transplant and healthy children whose siblings had no chronic conditions. RESULTS: The siblings of children with kidney transplant (n: 65), liver transplant (n: 35), and chronic rheumatic diseases (n: 36) were compared to the healthy children group (n: 51). The total siblings group had a lower, statistically significant score in the physical well-being, social support and peers, and financial resources dimensions. The siblings of kidney transplant patients had a low score in the physical wellbeing (p < 0.02; effect size [ES]: 0.66) andfinancial resources (p < 0.01; ES: 0.66) dimensions. The siblings of liver transplant patients perceived a lower physical well-being (p = 0.04), less social support and peers (p < 0.01), and difficulties in relation to school environment (p < 0.02) and financial resources (p <0.01). The siblings of those with chronic rheumatic diseases had a lower score in the physical well-being (p < 0.05; ES: 0.44) and social support and peers (p <0.01; ES: 0.58) dimensions. CONCLUSION: HRQoL among healthy children whose siblings have a chronic disease was lower in the physical well-being, social support and peers, and financial resources dimensions compared to the healthy children group.

Introducción. La calidad de vida relacionada con la salud (CVRS) es una medida de resultado de salud. Evalúa el impacto subjetivo y global de las enfermedades en la vida cotidiana. Brinda información multidimensional sobre el bienestar físico, relación familiar y sus pares. Los estudios de CVRS de hermanos son limitados. Objetivo. Comparar CVRS de los hermanos de pacientes pediátricos con patologías reumáticas crónicas, trasplante renal o hepático con la de niños sanos con hermanos sin enfermedades crónicas. Resultados. Se compararon hermanos de niños con trasplante renal (n: 65), trasplante hepático (n: 35) y patologías reumáticas crónicas (n: 36) con el grupo control de niños sanos (n: 51). El grupo total de hermanos tuvieron puntuación más baj a, estadísticamente significativa, enlas dimensiones bienestar físico, amigos-apoyo social y recursos económicos. Los hermanos de trasplante renal tuvieron baja puntuación en las dimensiones de bienestar físico (p < 0,02; tamaño del efecto -TE-: 0,66) y recursos económicos (p < 0,01; TE: 0,66). Los hermanos de trasplante hepático percibieron menor bienestar físico (p = 0,04), tenían menos amigos y apoyo social (p < 0,01), dificultades en el entorno escolar (p < 0,02) y recursos económicos (p < 0,01). Los hermanos de patologías reumáticas crónicas tuvieron menor bienestar físico (p < 0,05; TE: 0,44) y apoyo social-amigos (p < 0,01; TE: 0,58). Conclusión. La CVRS de niños/as sanos de hermanos con patologías crónicas es menor en bienestar físico, amigos-apoyo social y recursos económicos comparada con el grupo de niños sanos.

[Tubulointerstitial nephritis associated with parvovirus beta19 infection]. / Nefritis tubulo intersticial asociada a parvovirus B19.

A previously healthy 9 year old girl developed nephrotic syndrome with hypertension, microhematuria and normal renal function. The patient evolved as steroid resistant nephrotic syndrome whose initial renal biopsy was consistent with diffuse proliferative mesangial glomerulonephritis with focal segmental glomerulosclerosis. At the time of cyclophosphamide and prednisone treatment, she developed a prolonged febrile syndrome. She also had severe anemia following an aplastic crisis induced by human parvovirus B19 infection and acute renal failure secondary to a severe tubulointersticial disease. Bone marrow and renal tissue, tested by polimerase chain reaction were positive for parvovirus, while the patient's blood was negative. The renal involvement did not improve requiring chronic dialysis support. We believe that the initial glomerular disease could have been due to a parvovirus infection followed by un unexpected acute tubular interstitial nephritis, rapidly progressing to chronic renal disease. This case represents, to our knowledge, the first time that a direct relationship between parvovirus infection and acute tubulointerstitial disease has been demonstrated.

Calidad de vida de los hermanos de pacientes con enfermedad crónica / Quality of life among siblings of patients with chronic conditions

Introducción. La calidad de vida relacionada con la salud (CVRS) es una medida de resultado de salud. Evalúa el impacto subjetivo y global de las enfermedades en la vida cotidiana. Brinda información multidimensional sobre el bienestar físico, relación familiar y sus pares. Los estudios de CVRS de hermanos son limitados.Objetivo. Comparar CVRS de los hermanos de pacientes pediátricos con patologías reumáticas crónicas, trasplante renal o hepático con la de niños sanos con hermanos sin enfermedades crónicas.Resultados. Se compararon hermanos de niños con trasplante renal (n: 65), trasplante hepático (n: 35) y patologías reumáticas crónicas (n: 36) con el grupo control de niños sanos (n: 51). El grupo total de hermanos tuvieron puntuación más baja, estadísticamente significativa, en las dimensiones bienestar físico, amigos-apoyo social y recursos económicos. Los hermanos de trasplante renal tuvieron baja puntuación en las dimensiones de bienestar físico (p < 0,02; tamaño del efecto ­TE­: 0,66) y recursos económicos (p < 0,01; TE: 0,66). Los hermanos de trasplante hepático percibieron menor bienestar físico (p = 0,04), tenían menos amigos y apoyo social (p < 0,01), dificultades en el entorno escolar (p < 0,02) y recursos económicos (p < 0,01). Los hermanos de patologías reumáticas crónicas tuvieron menor bienestar físico (p < 0,05; TE: 0,44) y apoyo social-amigos (p < 0,01; TE: 0,58).Conclusión. La CVRS de niños/as sanos de hermanos con patologías crónicas es menor en bienestar físico, amigos-apoyo social y recursos económicos comparada con el grupo de niños sanos.

Introduction. Health-related quality of life (HRQoL) is a measure of health outcomes. It assesses the subjective and overall impact of diseases on daily life. It also provides multidimensional data about physical well-being, family and peers relations. HRQoL studies on siblings are limited.Objective. To compare HRQoL among siblings of pediatric patients with chronic rheumatic diseases, kidney or liver transplant and healthy children whose siblings had no chronic conditions.Results. The siblings of children with kidney transplant (n: 65), liver transplant (n: 35), and chronic rheumatic diseases (n: 36) were compared to the healthy children group (n: 51). The total siblings group had a lower, statistically significant score in the physical well-being, social support and peers, and financial resources dimensions. The siblings of kidney transplant patients had a low score in the physical well-being (p < 0.02; effect size [ES]: 0.66) and financial resources (p < 0.01; ES: 0.66) dimensions. The siblings of liver transplant patients perceived a lower physical well-being (p = 0.04), less social support and peers(p < 0.01), and difficulties in relation to school environment (p < 0.02) and financial resources (p < 0.01). The siblings of those with chronic rheumatic diseases had a lower score in the physical well-being (p < 0.05; ES: 0.44) and social support and peers (p < 0.01; ES: 0.58) dimensions.Conclusion. HRQoL among healthy children whose siblings have a chronic disease was lower in the physical well-being, social support and peers, and financial resources dimensions compared to the healthy children group.

Impact of global economic disparities on practices and outcomes of chronic peritoneal dialysis in children: insights from the International Pediatric Peritoneal Dialysis Network Registry.

UNLABELLED: BACKGROUND, OBJECTIVES, AND METHODS: The number of patients on chronic peritoneal dialysis (CPD) is increasing rapidly on a global scale. We analyzed the International Pediatric Peritoneal Dialysis Network (IPPN) registry, a global database active in 33 countries spanning a wide range in gross national income (GNI), to identify the impact of economic conditions on CPD practices and outcomes in children and adolescents. RESULTS: We observed close associations of GNI with the fraction of very young patients on dialysis, the presence and number of comorbidities, the prevalence of patients with unexplained causes of end-stage kidney disease, and the rate of culture-negative peritonitis. The prevalence of automated PD increased with GNI, but was 46% even in the lowest GNI stratum. The GNI stratum also affected the use of biocompatible peritoneal dialysis fluids, enteral tube feeding, calcium-free phosphate binders, active vitamin D analogs, and erythropoiesis-stimulating agents (ESAs). Patient mortality was strongly affected by GNI (hazard ratio per $10 000: 3.3; 95% confidence interval: 2.0 to 5.5) independently of young patient age and the number of comorbidities present. Patients from low-income countries tended to die more often from infections unrelated to CPD (5 of 9 vs 15 of 61, p = 0.1). The GNI was also a strong independent predictor of standardized height (p < 0.0001), adding to the impact of congenital renal disease, anuria, age at PD start, and dialysis vintage. Patients from the lower economic strata (GNI < $18 000) had higher serum parathyroid hormone (PTH) and lower serum calcium, and achieved lower hemoglobin concentrations. No impact of GNI was observed with regard to CPD technique survival or peritonitis incidence. CONCLUSIONS: We conclude that CPD is practiced successfully, albeit with major regional variation related to economic differences, in children around the globe. The variations encompass the acceptance of very young patients and those with associated comorbidities to chronic dialysis programs, the use of automated PD and expensive drugs, and the diagnostic management of peritonitis. These variations in practice related to economic difference do not appear to affect PD technique survival; however, economic conditions seem to affect mortality on dialysis and standardized height, a marker of global child morbidity.

Defining left ventricular hypertrophy in children on peritoneal dialysis.

BACKGROUND AND OBJECTIVES: Left ventricular hypertrophy (LVH) is an important end point of dialysis-associated cardiovascular disease. The objective of this study was to evaluate the effect of different pediatric reference systems on the estimated prevalence of LVH in children on chronic peritoneal dialysis (CPD). DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS: Echocardiographic studies in 507 pediatric CPD patients from neonatal age to 19 years were collected in 55 pediatric dialysis units around the globe. We compared the prevalence of LVH on the basis of the traditional cutoff of left ventricular mass (LVM) index (>38.5 g/m(2.7)) with three novel definitions of LVH that were recently established in healthy pediatric cohorts. RESULTS: Application of the new reference systems eliminated the apparently increased prevalence of LVH in young children obtained by the traditional fixed LVM index cutoff currently still recommended by consensus guidelines. However, substantial differences of LVM distribution between the new reference charts resulted in a marked discrepancy in estimated LVH prevalence ranging between 27.4% and 51.7%. CONCLUSIONS: Although our understanding of the anthropometric determinants of heart size during childhood is improving, more consistent normative echocardiographic data from large populations of healthy children are required for cardiovascular diagnostics and research.

Nefritis tubulo intersticial asociada a parvovirus B19. / [Tubulointerstitial nephritis associated with parvovirus beta19 infection]

A previously healthy 9 year old girl developed nephrotic syndrome with hypertension, microhematuria and normal renal function. The patient evolved as steroid resistant nephrotic syndrome whose initial renal biopsy was consistent with diffuse proliferative mesangial glomerulonephritis with focal segmental glomerulosclerosis. At the time of cyclophosphamide and prednisone treatment, she developed a prolonged febrile syndrome. She also had severe anemia following an aplastic crisis induced by human parvovirus B19 infection and acute renal failure secondary to a severe tubulointersticial disease. Bone marrow and renal tissue, tested by polimerase chain reaction were positive for parvovirus, while the patients blood was negative. The renal involvement did not improve requiring chronic dialysis support. We believe that the initial glomerular disease could have been due to a parvovirus infection followed by un unexpected acute tubular interstitial nephritis, rapidly progressing to chronic renal disease. This case represents, to our knowledge, the first time that a direct relationship between parvovirus infection and acute tubulointerstitial disease has been demonstrated.