View metadata, citation and similar papers at core.ac.uk brought to you by CORE provided by Elsevier - Publisher Connector original article http://www.kidney-international.org & 2006 International Society of Nephrology see commentary on page 17 3–5 year longitudinal follow-up of pediatric patients after acute renal failure DJ Askenazi1, DI Feig1,2, NM Graham3, S Hui-Stickle1, SL Goldstein1,4 1Department of Pediatric Nephrology, Baylor College of Medicine, Houston, Texas, USA; 2Director of Pediatric Hypertensive Clinic, Baylor College of Medicine, Houston, Texas, USA; 3Dialysis Unit, Texas Children’s Hospital, Houston, Texas, USA and 4Director of Dialysis Unit, Texas Children’s Hospital, Houston, Texas, USA Few data exist regarding the long-term sequelae of acute Acute renal failure (ARF) is defined as the abrupt inability of the renal failure (ARF), and these studies are limited to a few kidneys to eliminate waste products and regulate electrolyte/ renal conditions. We aim to assess the 3–5-year survival and water metabolism. Patients who suffer an ARF episode may incidence of renal injury in children who previously have subsequent renal dysfunction after the original injury, and developed ARF of varying causes. We queried parents, children may be more susceptible to this injury due to the physicians, and hospital/state vital statistics records to find ongoing growth of the kidney during childhood. Some data that patient survival in 174 children who previously had ARF and describe long-term renal sequelae in children who had ARF due survived to hospital discharge. We assessed the following in to congenital heart diseases,1 Henoch–Schonlein purpura,2 very 29 children for residual renal injury: (a) microalbuminuria, (b) low birth weight neonates,3 and hemolytic uremic syndrome glomerular filtration rate (GFR) by Schwartz formula, (c) exist.4 Persistent microalbuminuria is common in women 3–5 hypertension, and (d) hematuria. The 3–5-year survival of years after a pre-eclampsia episode.5 Studies in adults6 have children with ARF who survived to hospital discharge was found ongoing renal injury after ARF of multiple etiologies, but 139/174 (79.9%). Most deaths (24/35 (68.5%)) occurred these studies may not be extrapolated to children, since adults within 12 months after initial hospitalization. Combining demonstrate higher rates of comorbid illnesses than children. those who died during initial hospitalization and in In the 1980s, intrinsic renal disease and burns comprised the subsequent 3–5 years, the overall survival rate was 139/245 most common pediatric ARF etiologies.7–13 A recent study (56.8%). In all, 16 children progressed to end-stage renal performed in our institution between January 1998 and disease; thus, renal survival was 127/173 (91%). Those with December 2001 found that the epidemiology of pediatric primary renal/urologic conditions had lower renal survival patients with the diagnosis of ARF has broadened over the last than others (24/35 (68.6%) vs 134/139 (96.4%); Po0.0001). decade.14 Now, pediatric ARF most often results from Among the 29 patients assessed for long-term sequelae at complications of other systemic diseases resulting from the 3–5 years, 17/29 (59%) subjects had at least one sign of renal advancements in congenital heart surgery, neonatal care, and injury; microalbuminuria (n ¼ 9), hyperfiltration (n ¼ 9), bone marrow and solid organ transplantation. That study decreased GFR (n ¼ 4), and hypertension (n ¼ 6). A pediatric showed that 174/245 (71%) patients survived the initial nephrologist was involved in care of only 6/17 (35%) with hospitalization. At hospital discharge, 68% of survivors chronic renal injury. Patients have high risks of ongoing recovered complete renal function, 13% had improved renal residual renal injury and death after ARF; therefore, periodic function, 12% sustained renal failure, and 5% progressed to evaluation after the initial insult is necessary. end-stage renal disease (ESRD). Determining the natural history Kidney International (2006) 69, 184–189. doi:10.1038/sj.ki.5000032 following an ARF episode will help clinicians design appropriate KEYWORDS: acute renal failure; renal survival; long-term survival; chronic monitoring programs. If renal injury is common, therapeutic renal injury; microalbuminemia; hypertension interventions to prevent progression of renal injury can be sought. In order to assess the long-term outcome of children with a variety of ARF causes, we conducted a follow-up study to determine patient and renal survival, to look for signs of kidney injury, and to assess the health-related quality of life of the original cohort. To our knowledge, this is the first analysis to describe the long-term outcome of children after ARF. Correspondence: DJ Askenazi, Department of Pediatric Nephrology, RESULTS University of Alabama at Birmingham, 1600 7th Avenue South, ACC 516, Epidemiology Birmingham, Alabama, 35322, USA. E-mail: [email protected] Initial hospital survival. The hospital survival after an ARF Received 29 April 2005; revised 24 June 2005; accepted 11 August 2005 episode at Texas Children’s Hospital between January 1998 184 Kidney International (2006) 69, 184–189 DJ Askenazi et al.: Follow-up of children after ARF original article Table 1 | Survival in children after ARF Ren/Uro All Patients No ICU ICU Initial RRT No initial RRT comorbid No Ren/Uro Hospital survival 174/245 (71.0%) 65/66 (98.5%) 109/179 (60.9%) Po0.001 44/75 (58.7%) 130/170 (76.5%) Po0.01 35/37 (94.6%) 139/208 (66.8%) Po0.001 3–5-year survival of 139/174 (79.9%) 54/65 (83.0%) 85/109 (78.0%) NS 31/44 (70.5%) 108/130 (83.1%) NS 31/35 (88.6%) 108/139 (77.7%) NS hospital survivors Renal survival 158/174 (90.8%) 56/65 (86.1%) 102/109 (93.6%) NS 37/44 (84.1%) 121/130 (93.1%) NS 24/35 (68.6%) 134/139 (96.4%) Po0.0001 Ren, renal; RRT, renal replacement therapy; Uro, urology. and June 2001 was 174/245 (71%). Patients who required 245 children with ARF at TCH renal replacement therapy (RRT), intensive care unit (ICU) January 1998 − June 2001 admission, and those without primary renal/urologic condi- 71 did not survive 174 survived tions were less likely to survive hospitalization (Table 1; data 14 from Hui-Stickle et al. ). 32 died after discharge 16 ESRD 126 potential subjects Survival at 3–5 years of initial hospital survivors. The 3–5- Parent or MD report year survival rate for the children with ARF who survived to hospital discharge was 139/174 (79.9%). No survival dif- 3 Died 69 Unable to locate 28 Did not show or ference was seen for patients with ICU admission vs without 13 Alive ICU admission, receiving initial RRT vs not receiving initial refused RRT, or renal/urologic vs no renal/urologic comorbidity 29 Subjects (Table 1). Of the 35 deaths that occurred after initial hospital Figure 1 | 3–5-year outcomes of children who developed ARF at discharge, 24/35 (68.5%) occurred within 12 months and 31/35 Texas Children’s Hospital between January 1998 and June 2001. (88.6%) occurred within 24 months after initial hospitalization. In total, 29 subjects were further evaluated for signs of chronic renal injury. Renal survival. Of the initial hospital survivors, at least 16 children progressed to ESRD (three of these have died); thus, the renal survival at 3–5 years was 158/174 (90.8%). ESRD Table 2 | Demographics of potential participants occurred more commonly in patients with primary renal/ Came Did not come urologic conditions vs others (24/35 (68.6%) vs 133/139 (n=29) (n=97) (95.7%); Po0.0001). Neither ICU admission nor the initial Age at hospital admission 6.475.8 6.476.5 NS need for RRT was predictive of long-term renal survival. Age at follow-up 9.876.5 12.177.2 NS Years after event 3.770.9 4.171.1 NS Renal injury Ethnicity NS Patient population. In all, 119/245 of the original cohort Caucasian 11 (38%) 35 (36.1%) were known to have either (a) ESRD or (b) died during or Hispanic 10 (34%) 27 (27.9%) after hospitalization; thus, 126 children were available for African American 6 (21%) 27 (27.9%) Asian 0 (0%) 4 (4.1%) renal injury assessment. Also, 69 subjects did not respond by Other 2 (7%) 4 (4.1%) phone or mail and 28 subjects refused to participate. Reasons No. of male patients 13 (44.9%) 57 (58.8%) NS for refusal included: ‘too busy’ (n ¼ 8), ‘adequate follow-up’ RRT 6 (20.7%) 20 (20.6%) NS (n ¼ 3), ‘too hard’ (n ¼ 2), ‘live too far’ (n ¼ 1), refused to Hypertensive at the time of ARF 9 (31.0%) 27 (27.8%) NS give a reason (n ¼ 3), and did not show (n ¼ 11). We Urine output at the time of ARF 3.073.5 2.672.2 NS evaluated 29/126 (23%) of potential subjects for signs of (ml/kg/h) GFR minimum (ml/min/1.73 m2) 25.7719.2 26.1720.4 NS renal injury and health-related quality of life between Length of stay (days) 18.6721.5 12.8733.3 NS February and July 2004 (Figure 1). No. of patients with primary 10 (34.4%) 12 (12.4%) Po0.01 Participants in the study and those who were lost or renal/urologic conditions refused to participate in the study did not differ with regard No. of patients requiring ICU stay 17 (58.6%) 64(64.3%) NS to demographics, length of stay, frequency of ICU hospita- Outcome at discharge (no. of patients) NS lization, severity of renal failure, and outcome at the time of Normal 21 (72.4%) 67 (69.1%) Improve 6 (20.7%) 18 (18.6%) discharge.