IgA-Dominant Postinfectious Glomerulonephritis: Not Peculiar to Staphylococcal Infection and Diabetic Patients

Background: IgA-dominant postinfectious glomerulonephritis (PIGN) is a unique form of PIGN. It has been linked to staphylococcal infection and underlying diabetic glomerulosclerosis. However, the significance of glomerular IgA-dominant deposition in PIGN remains unclear. Methods: We reported 10 patients with IgA-dominant PIGN encountered at a single center, each characterized by subepithelial humps. Their demographic, clinical, and renal biopsy findings were summarized and compared with the data of 32 patients with non-IgA-dominant PIGN. Results: The mean age was 57 years. An immunocompromised background was present in 70% of patients; only one patient had diabetes mellitus. The causative infectious agents included Staphylococcus (30%), Streptococcus (20%), and gram-negative organisms (50%). Decreased serum complement was present in 60%. Increased serum IgA was noted in 75%. The mean peak serum creatinine was 5.1?mg/dL, and 20% required acute dialysis. Diffuse endocapillary-proliferative glomerulonephritis was found in all cases, and three patients also had crescentic glomerulonephritis. Electron microscopy revealed large subepithelial hump-shaped deposits in all cases. At the last follow-up, one patient had died, five had achieved complete recovery, three had persistent renal insufficiency, and one was on chronic dialysis. Compared to patients with non-IgA-dominant PIGN, increased serum IgA was more commonly present in IgA-dominant group (p?=?0.007). There were no significant differences in other clinical parameters and outcome between the two groups. Conclusions: IgA-dominant PIGN resembles poststreptococcal glomerulonephritis in its histological spectrum and ultrastructural appearance. Increasing serum IgA may be involved in the pathogenesis of this form of PIGN. Our data suggested that IgA-dominant PIGN was not peculiar to staphylococcal infection and diabetic patients.     

Acute Kidney Injury After Pediatric Liver Transplantation

BackgroundThe aim of the present study is to assess acute kidney injury (AKI) incidence according to the pRIFLE and AKIN criteria and to evaluate the risk factors for early developing AKI in postoperative intensive care unit after pediatric liver transplantation (LT).MaterialsAfter exclusion of retransplantations, 7 cadaveric and 44 living donors, totaling 51 pediatric LT patients that were performed between 2005 and 2017, were reviewed retrospectively. AKI was defined according to both pediatric RIFLE (Risk for renal dysfunction, Injury to the kidney, Failure of kidney function, Loss of kidney function, and End-stage renal disease) and Acute Kidney Injury Network (AKIN) criteria. Documented data were compared between AKI and non-AKI patients.ResultsAKI incidences were 17.6% by AKIN and 37.8% by pRIFLE criteria. AKIN-defined AKI group had statistically lower serum albumin level, higher serum sodium level, higher furosemide dose, and higher rate of red blood cell (RBC) transfusion than the non-AKI group (P = .02, P = .02, P = .01 and P = .04, respectively). AKI patients had significantly prolonged mechanical ventilation (P = .01) and hospital LOS (P = .02). The pRIFLE-defined AKI group had significantly lower serum albumin level, higher blood urea nitrogen (BUN) level, and higher ascites drained and also showed higher requirement for RBC and 20% human albumin transfusions than the non-AKI group (P = .02, P = .04, P: =.007, P = .02 and P = .05, respectively).ConclusionWe evaluated that hypoalbuminemia, high requirement for RBC and 20% human albumin transfusions, high serum sodium, high furosemide use, and high flow of ascites are risk factors for AKI and high BUN levels can be predictive for AKI in pediatric LT patients. The effect of AKI on outcome variables were prolonged mechanical ventilation and hospital LOS.     

A rare case of postinfectious glomerulonephritis caused by pneumococcus in an adult patient

Postinfectious glomerulonephritis (PIGN) is commonly seen as a complication of infection with nephritogenic strains of group A streptococci, mostly with Streptococcus pyogenes. Pneumococcal pneumonia leading to glomerulonephritis has been reported in the pediatric literature, but only one adult case has been previously reported. We are presenting a case of postinfectious glomerulonephritis caused by pneumococcal pneumonia in an adult. In the present case, other possible etiologies of nephritic syndrome were ruled out with negative antineutrophilic cytoplasmic antibody (ANCA), anti-glomerular basement membrane antibody (Anti-GBM), antistreptolysin O (ASO), antinuclear antibody (ANA), HIV and viral hepatitis profile. The low CH50 indicated a complement-mediated injury. Renal biopsy was done showing immune complex-mediated crescentic glomerulonephritis consistent with postinfectious etiology. The patient received pulse dose steroids for 5 days followed by oral steroids. His urinary output improved along with normalization of his renal function, therefore dialysis was discontinued. We are presenting this case to alert clinicians to the possibility of postinfectious glomerulonephritis following pneumococcal pneumonia and to report the successful use of steroid therapy in such a situation.     

Acute kidney injury

Acute kidney injury (AKI) is defined as an abrupt decline in the glomerular filtration rate with accumulation of nitrogenous waste products and the inability to maintain fluid and electrolyte homeostasis. Occurring in 7% of all hospitalized patients and 28% to 35% of those in intensive care units, AKI increases hospital mortality. Early evaluation should include differentiating prerenal and postrenal components from intrinsic renal disease. Biological markers can give early warning of AKI and assist with differential diagnosis and assessment of prognosis. The most effective preventive measure is to maintain adequate circulation and cardiac output, avoiding ischemia- or nephrotoxin-induced injury. To that end, patients and situations of risk must be identified, hemodynamics and diuresis monitored, hypovolemia reversed, and nephrotoxins avoided. Protective agents such as sodium bicarbonate, mannitol, prostagiandins, calcium channel blockers, N-acetyl-L-cysteine, sodium deoxycholate, allopurinol, and pentoxifylline should be used. Treatment includes the elimination of prerenal and postrenal causes of AKI; adjustment of doses according to renal function; avoidance of both overhydration and low arterial pressure; maintenance of electrolytic balance, avoiding hyperkalemia and correcting hyperglycemia; and nutritional support, assuring adequate protein intake. For severe AKI, several modalities of renal replacement therapy, differentiated by mechanism and duration, are available. Timing--neither the best moment to start dialysis nor the optimal duration--has been not established. Early detection of AKI is necessary for preventing progression and starting renal replacement therapy at adjusted doses that reflect metabolic requirements.     

Acute kidney injury according to pediatric RIFLE criteria is associated with negative outcomes after heart surgery in children

Background

The aim of this study was to investigate the association between the occurrence of acute kidney injury (AKI) according to pediatric RIFLE (pRIFLE) criteria and adverse outcomes in children after heart surgery.

Methods

Children undergoing heart surgery in a tertiary hospital in Southern Brazil were followed during their stay in the pediatric intensive care unit (PICU) or until death. The exposure variable was occurrence of AKI according to pRIFLE criteria which place AKI in three categories: R (risk), I (injury), and F (failure). The outcomes studied were death, length of mechanical ventilation (MV), and length of PICU stay.

Results

Eighty-five children were enrolled in the study. Of these, 47 (55.3 %) did not have AKI, while 22 (25.9 %), seven (8.2 %), and nine (10.6 %) were classified into pRIFLE categories R, I, and F, respectively. The incidence of death was 18.4 and 4.2 % in patients with and without AKI, respectively. Compared to children who did not develop AKI, the adjusted odds ratio for death was 1.05 [95 % confidence interval (CI) 0.09–11.11], 8.36 (95 % CI 1.32–52.63), and 7.85 (95 % CI 1.53–40.29) in the R, I, and F groups, respectively (p?=?0.022). Duration of MV and of PICU stay were significantly higher in those children with AKI.

Conclusions

The occurrence of AKI according to pRIFLE criteria is associated to adverse outcomes in children after heart surgery.     

Urinary neutrophil gelatinase-associated lipocalin distinguishes pre-renal from intrinsic renal failure and predicts outcomes

In established acute kidney injury (AKI), serum creatinine poorly differentiates prerenal from intrinsic AKI. In this study, we tested whether urinary neutrophil gelatinase-associated lipocalin (NGAL) distinguishes between intrinsic and prerenal AKI, and tested its performance in predicting a composite outcome that included progression to a higher RIFLE (Risk, Injury, Failure, Loss of function, End stage renal disease) class, dialysis, or death. Urinary NGAL was measured using a standardized clinical platform in 161 hospitalized patients with established AKI. Sixteen patients were excluded because of postrenal obstruction or insufficient clinical information. Of the remaining 145 patients, 75 had intrinsic AKI, 32 had prerenal AKI, and 38 patients could not be classified. Urinary NGAL levels effectively discriminated between intrinsic and prerenal AKI (area under the receiver-operating characteristic curve 0.87). An NGAL level over 104?μg/l indicated intrinsic AKI (likelihood ratio 5.97), whereas an NGAL level <47?μg/l made intrinsic AKI unlikely (likelihood ratio 0.2). Patients experiencing the composite outcome had significantly higher median urinary NGAL levels on inclusion. In logistic regression analysis, NGAL independently predicted the composite outcome when corrected for demographics, comorbidities, creatinine, and RIFLE class. Hence, urinary NGAL is useful in classifying and stratifying patients with established AKI.     

Pediatric acute kidney injury assessed by pRIFLE as a prognostic factor in the intensive care unit

Background

In this study we applied the pediatric version of the RIFLE criteria (pRIFLE) to an at-risk hospital population, analyzed the incidence and association of acute kidney injury (AKI) with mortality and length of stay in both the intensive care unit (ICU) and the hospital, and evaluated the applicability of pRIFLE as a prognostic tool in the ICU.

Methods

This study was a prospective single-center cohort study in which 126 patients were enrolled. The affected group included patients who were diagnosed with AKI. Subgroups of the diagnosed patients were established according to their maximum pRIFLE strata, which were defined as the worst pRIFLE score attained during the study period.

Results

Fifty-eight (46 %) of our patients developed AKI. The lengths of stay in the ICU and in the hospital were longer in the affected group than in the unaffected group. The advanced strata of pRIFLEmax were associated with longer stays in the ICU and hospital and higher median Pediatric Index of Mortality II scores. The hospital mortality rate of AKI patients was 12-fold higher than that of the patients without AKI (36 vs. 3 %).

Conclusion

The incidence of AKI in this population was both significant and directly associated with hospital mortality and the length of stay in the ICU and hospital. The pRIFLE classification facilitated the definition of AKI, indicating that it a significant prognostic predictor.     

Acute kidney injury caused by ceftriaxone-induced urolithiasis in children: a single-institutional experience in diagnosis,treatment and follow-up

Purpose

To evaluate our clinical outcomes in managing acute kidney injury (AKI) resulting from ceftriaxone-induced urolithiasis with emergency treatment.

Methods

From July 2008 to July 2013, a series of 15 patients including 12 males and 3 females were admitted to our center. The mean age of them was (4.76 ± 3.74) years. A chief complaint of anuria was presented in 12 (80.0 %) patients for 13 h–4 days and that of oliguria in three (20.0 %) patients for 20 h–10 days. All of them were diagnosed of postrenal AKI resulting from ceftriaxone-induced urolithiasis and underwent emergency hospitalization.

Results

Double-J stenting with cystoscopy was successfully performed in nine patients (60.0 %), and ureteroscopy was applied in four patients (26.7 %). One patient (6.7 %) underwent unilateral double-J insertion combined with contralateral percutaneous nephrostomy, and one (6.7 %) underwent open surgery. Loose texture and sandlike stones, the main characteristics of these stones, made them excreted spontaneously after the initial treatment, whereas only one patient (6.7 %) underwent additional ureterolithotomy due to many residual calculi. Serum creatinine and blood urea nitrogen recovered to normal levels within 3 days. All specimens were collected and analyzed by infrared spectrum, with results demonstrating that the main composition was ceftriaxone calcique. All patients were followed up for 11 months–5 years (mean 33.80 ± 22.56 months). No one turned to irreversible renal failure.

Conclusions

Ceftriaxone could result in urolithiasis in children, which could also cause AKI. Appropriate and timely surgical management by conventional treatments will mostly lead to full recovery of renal functions.     

Prognostic relevance of early AKI according to pRIFLE criteria in children undergoing cardiac surgery

Background

Acute renal injury increases risk of death after cardiac surgery. The objective of the study was to evaluate the ability of the pediatric Risk, Injury, Failure, Loss, End-Stage Renal Disease (pRIFLE) criteria to characterize the development of postoperative renal damage in children after cardiopulmonary bypass (CPB) and to evaluate the relationship between the severity of kidney injury and mortality, pediatric intensive care unit (PICU) length of stay, and the duration of mechanical ventilation (MV).

Methods

In this retrospective study including children undergoing CPB surgery during a 3-year period in the PICU of a tertiary hospital, demographic, clinical, surgery-related, and postoperative clinical data were collected. Kidney damage was assessed with pRIFLE criteria.

Results

Four hundred and nine patients were included. Early acute kidney injury (AKI) was found in 82 patients (achieving categories Risk 44; Injury 16; Failure 22). Early AKI was associated with younger age (P?=?0.010), longer CPB, deep hypothermic circulatory arrest (DHCA) use, ICU stay >12 days, MV >4 days, and death (P?<?0.001). Controlling the effect of age, CPB, DHCA use, previous cardiac surgeries, and Risk Adjustment in Congenital Heart Surgery Surgical Severity Score (RACHS-1), early AKI development proved to predict ICU stay >12 days [odds ratio (OR) 3.5; 95 % confidence interval (CI) 1.9–6.5, P?<?0.001)] and need of MV >4 days (OR 5.1; 95 % CI 2.6–10.2, P?<?0.001).

Conclusions

Early AKI when evaluated with the pRIFLE criteria can predict prolonged ICU stay, need of prolonged MV, and mortality.     

C3 Glomerulopathy and post-infectious glomerulonephritis define a disease spectrum

Background

Post-infectious glomerulonephritis (PIGN) usually follows a benign course, but few children have an atypical, severe presentation, and these exceptional cases have been linked to the dysregulation of the complement alternative pathway (CAP). There is a considerable overlap in the histopathological features of PIGN and C3 glomerulopathy (C3G), which is also associated with CAP dysregulation but has a poorer outcome. We hypothesized that PIGN and C3G define a disease spectrum, and that in the past there may be some children with C3G who were misclassified with PIGN before C3G was described as a separate disease entity.

Methods

Children with PIGN (n?=?33) diagnosed between 1985 and 2010 who underwent a renal biopsy due to their unusual course were reviewed and of them, 8 were reclassified into C3G based on the current classification criteria. Outcome was based on the degree of proteinuria, C3 level, and renal function at follow-up.

Results

Sixteen (72.7%) children with typical PIGN recovered completely as compared to only 2 (25%) with C3G. Of note, children with “typical” PIGN had a more severe disease course at onset; however, the outcome at last follow up was favorable.

Conclusions

Our results support the hypothesis that PIGN and C3G form a disease spectrum and have different long-term clinical implications and management strategies.

     

Discrimination between postinfectious IgA-dominant glomerulonephritis and idiopathic IgA nephropathy

Background: A unique form of postinfectious glomerulonephritis (PIGN) with IgA-dominant deposition mimicking IgA nephropathy has been increasingly reported. Methods: We compared the clinical and histological features of 12 patients with postinfectious IgA-dominant glomerulonephritis to 134 patients with idiopathic IgA nephropathy. Results: In addition to hypocomplementemia and subepithelial hump-shaped deposits characteristic of PIGN, patients with postinfectious IgA-dominant glomerulonephritis had older age (62.3 ± 16.9 vs. 37.9 ± 16.3 years; p < 0.001) and more frequently presented with acute renal failure (83.3% vs. 10.4%; p < 0.001) than patients with idiopathic IgA nephropathy. Moreover, glomerular changes including endocapillary proliferation, neutrophil infiltration, and capillary loops deposits by immunofluorescence were more commonly present in postinfectious IgA-dominant glomerulonephritis group (p < 0.001). Conclusions: PIGN could be characterized by glomerular IgA-dominant deposition resembling idiopathic IgA nephropathy. It is essential to differentiate postinfectious IgA-dominant glomerulonephritis from idiopathic IgA nephropathy because of the different treatments and prognosis of the two diseases.     

Long-term renal outcome in pediatric glomerulonephritis associated with crescent formation

Background

Information on long-term renal outcome of pediatric glomerulonephritis associated with crescent formation is limited. A single center retrospective study was conducted to assess long-term renal survival and to determine whether the 2010 classification for antineutrophil cytoplasmic antibody (ANCA)-associated glomerulonephritis can predict renal outcome in pediatric glomerulonephritis associated with crescent formation.

Methods

Biopsy and clinical data of children, aged ≤ 18 years with ≥ 10 glomeruli and ≥ 10% crescentic glomeruli during January 1998 to December 2015, were reviewed. Biopsies were classified according to the 2010 classification into focal, crescentic, mixed, and sclerotic classes. The clinical endpoint was end-stage renal disease (ESRD).

Results

Of 72 children, 14 patients (19.4%) had positive ANCA. The biopsy indication was rapidly progressive glomerulonephritis in 38 patients (52.8%) and 22 patients (30.6%) required dialysis at onset. Lupus nephritis was the most common diagnosis (43.1%), followed by IgA nephropathy/Henoch–Schoenlein purpura (HSP) (22.2%). ESRD occurred in 18 patients (25%) and the risk of ESRD differed among the histological classifications (p < 0.001). Dialysis at onset and sclerotic class was independent predictors of ESRD in an adjusted model. The risk of ESRD was four-fold higher in patients requiring dialysis at onset and 7.7-fold higher in sclerotic patients than in crescentic patients.

Conclusions

The probability of ESRD was substantial in pediatric glomerulonephritis associated with crescent formation. The 2010 classification is useful for establishing long-term renal prognosis. Future research is required to validate whether histological classification could be a determinant in therapeutic guideline modification, since long-term renal prognosis is different in each class.

     

Outcome of severe acute post-streptococcal glomerulonephritis in New Zealand children

Post-streptococcal glomerulonephritis (PSGN) is the commonest cause of severe acute glomerulonephritis in New Zealand children, with the majority (85%) of the patients being of either Pacific Island or Maori ethnicity. We have performed a retrospective study on 27 pediatric patients with acute PSGN. Of these patients, those with crescentic glomerulonephritis (n = 11) had a greater tendency (72.7%) for needing acute dialysis and were left with persistent urinary sediment abnormalities after a mean follow-up of 3.2 years (95% confidence interval 2.1–4.3). The efficacy of immunosuppression in the group with crescentic disease was uncertain. The severity of renal histopathological abnormalities as judged by the total biopsy score did not correlate with either presentation or eventual outcome. Severe childhood acute post-streptococcal glomerulonephritis, although uncommon, results in significant long-term renal morbidity, particularly among Maori and Pacific Island children.     

Incidence,characteristics and prognosis of acute kidney injury in Cameroon: a prospective study at the Douala General Hospital

Objective: There are limited data on AKI in sub-Saharan Africa. We aim to determine the incidence, characteristics and prognosis of AKI in Cameroon.

Patients and methods: A prospective study including all consenting acute admissions in the internal medicine and the ICU of a tertiary referral hospital in Cameroon from January 2015 to June 2016. Serum creatinine assay was done on admission, days 2 and 7 to diagnose AKI. For patients with AKI, serum creatinine was done on discharge, days 30, 60 and 90. AKI was defined according to the modified KDIGO 2012 criteria as an increase or decrease in serum creatinine of 3?mg/l or greater, or an increase of 50% or more from the reference value obtained at admission or the known baseline value. AKI severity was graded using KDIGO2012 criteria. Outcome measures were renal recovery, mortality and causes of death. Renal recovery was complete if serum creatinine between the first 90?days was less than baseline or reference, partial if less than diagnosis but not baseline or reference, no-recovery if creatinine did not decrease or if the patient remained on dialysis.

Results: Of the 2402 patients included, 536 developed AKI giving a global incidence of 22.3% and annual incidence of 15 per 100 patients-years. Of the 536 patients with AKI, 43.3% were at stage 3, 54.7% were males, median age was 56?years. Pre-renal AKI (61.4%) and acute tubular necrosis (28.9%) were the most frequent forms. Main etiologies were sepsis (50.4%) and volume depletion (31.6%). Renal outcome was unknown in 34% of patients. Of the 354 patients with known renal function at 3?months, 84.2% recovered completely, 14.7% partially and 1.1% progressed to CKD. Global mortality rate was 36.9% mainly due to sepsis.

Conclusions: AKI is frequent in our setting, mainly due to sepsis and hypovolemia. It carries a poor prognosis.     

Metabolic features and renal outcomes of urolithiasis in children

Aim: The incidence of pediatric urolithiasis has increased over the last century because of dietary changes, metabolic abnormalities, climate change, and genitourinary abnormalities. Data on pediatric urolithiasis in non-endemic countries are limited. The aim of this study was to evaluate the clinical findings and metabolic etiology of urolithiasis in Korean children. Material and methods: The medical records of 73 Korean children who were newly diagnosed with urolithiasis from January 2010 to December 2013 were retrospectively analyzed. Evaluation of metabolic risk factors, including hypercalciuria, hyperuricosuria, hypomagnesuria, hyperoxaluria, and hypocitraturia, required analysis of 24-h urine specimens or, alternatively, for infants and toddlers, the solute-creatinine ratio in spot urine. Results: The male-to-female ratio of the included patients was 1.3:1. The median age at diagnosis was 10.1 years, and the patients were divided into two age groups with pre-school-age children (n?=?27, 37.0%) and school-age children (n?=?46, 63.0%). While flank pain was more common in school-age children, incidentally detected or urinary tract infection (UTI)-associated urolithiasis was more common in pre-school-age children. Eight patients (11.0%) had renal function deterioration associated with urolithiasis, and three patients (4.1%) progressed to chronic kidney disease. Metabolic abnormalities according to urine chemistry were found in 30 patients (41.1%), including hypercalciuria in 21.9%, hyperuricosuria in 11.0%, hypomagnesuria in 4.1%, hyperoxaluria in 1.4%, hypocitraturia in 1.4%, and cystinuria in 1.4%. Conclusion: We suggest that school-age children with renal colic and pre-school-age children with UTI should be evaluated for urolithiasis. Additionally, the evaluation for metabolic risk factors is important in order to prevent recurrence and renal insufficiency.     

Urinary biomarkers to detect acute kidney injury in the pediatric emergency center

We conducted a prospective study in pediatric patients presenting to an emergency center (EC) to (1) test the ability of urinary acute kidney injury (AKI) biomarkers to predict AKI presence and severity and (2) determine if these biomarkers offer similar precision in patients with versus without a known baseline SCr. The accuracy of five putative urinary biomarkers to detect AKI presence and severity was evaluated in 252 children presenting to our EC. AKI was defined by the modified pediatric RIFLE (pRIFLE) system. Eighteen children had AKI by pRIFLE, yet 33–50% of these AKI cases may have been missed since the EC SCr was <1 mg/dl. Urinary NGAL, Kidney Injury Molecule-1 (KIM-1) and beta-2 microglobulin (β2M) all demonstrated good to very good accuracy (AUC > 0.70 to 0.80) to predict patients with pRIFLE-Injury (>50% decrease in eCCl) versus patients with pRIFLE-Risk (25–50% decrease in eCCl) or without AKI. Our data suggest urinary biomarkers may serve well to detect AKI accurately in the pediatric EC setting, even in cases where SCr levels are normal. Further study is required to determine if these biomarkers obtained in the EC can predict AKI development or progression in hospitalized patients.     

Frequency and outcome of patients with acute renal failure have more causes than one in etiology

In literature, there was little data about frequency and outcome of ARF with two or more causes in etiology. Therefore, the aim of this study was to search this issue. This series included 339 patients with ARF from Jan 1,1987 to Jan 1,1999. Fourty-six (30 males) of all patients (13.5%) had two or more causes in etiology of ARF. Of these patients, causes were prerenal and renal in 26 (56%), prerenal, renal and postrenal in 12 (26%), renal and postrenal in 4 (9%), and prerenal and postrenal in 4 (9%). The most frequent cause is diarrhea and vomiting in prerenal, gentamycin usage in renal and prostate hypertrophy in postrenal. Of these patients, there was oliguria in 32 (70%), anuria in 8 (17%) and non-oliguria in 6 (13%). Treatment modalities of patients was only medical in 19 (41%), dialysis in addition to medical therapy in 27 (59%). In spite of treatment, 5 (10.8) of patients with two or more causes in etiology died. Causes of death were uremic coma in 2, cardiac disorders in 2 and septic shock in 1. Three (11.2%) of other patients with one cause died. Mortality rates were not different (chi2: 0.0298, p > 0.5). Cortical necrosis was diagnosed in one patient with multiple etiology and 2 of other patients. Finally, frequency of ARF with two or more etiologic causes was 13.5%, and most frequent causes were hypovolemia and nephrotoxic drugs. Outcome of these patients was similar to other patients with one cause.     

Utility of fractional excretion of urea in the differential diagnosis of acute kidney injury in children

Introduction

The fractional excretion of sodium (FE_Na) has been used as an index for the differential diagnosis of acute tubular necrosis (ATN) and prerenal acute kidney injury (AKI). The reliability of this index, however, decreases with the use of the diuretic agent furosemide. The fractional excretion of urea nitrogen (FE_UN) has been shown to be useful in such settings in adults. The objective of this study was to examine whether FE_UN is also useful in these settings in children.

Methods

We assessed 102 episodes of AKI in 74 children, classifying these into three groups based on history, physical examination, urine examination and subsequent clinical course: (1) prerenal AKI without furosemide (N?=?37), (2) prerenal AKI with furosemide (N?=?32) and (3) ATN (N?=?33).

Results

Of the 37 prerenal AKI episodes without furosemide, 35 showed low FE_Na of <1 %, with an overall average of 0.35?±?0.11 %, whereas prerenal AKI with furosemide (1.63?±?0.37 %) and ATN (8.76?±?2.11 %) were associated with a higher FE_Na. FE_UN in the clinical setting of prerenal AKI was lower than that in ATN (27.9?±?2.1 vs. 51.6?±?3.8 %, respectively) and, in contrast to FE_Na, not significantly different between the categories of prerenal AKI with and without furosemide (29.2?±?3.1 vs. 25.1?±?2.9, respectively). The sensitivity of FE_UN <35 % was 75 % in prerenal AKI with furosemide, whereas that of FE_Na was 53 %.

Conclusions

FE_UN is useful in detecting prerenal AKI in children administered furosemide.

     

Epidemiological characteristics of childhood urolithiasis in Morocco

ObjectivesDue to the increase observed in the incidence of pediatric urolithiasis in the world, and the scarcity of studies of this pathology in Morocco, we assessed whether epidemiological characteristics of pediatric urolithiasis have a similar profile like in developed countries further we tried to assess the prevalence of this pathology among children in Hassan II University-Hospital of Fez.Subjects and methodsBetween January 2003 to November 2013, 104 pediatric patients with urolithiasis were presented to Hassan II University-Hospital of Fez. Eighty one were boys and 23 girls. Patients were referred from different regions of Moroccan states.ResultsOut of 104 children diagnosed with urolithiasis, 5 patients with positive family history of renal stones, and 12 were recurrent (12%).Their age varied between 8 months and 15 years old, with a mean age of 7.86 ± 4. The sex ratio was 3.5:1 boys to girls. Clinical presentations were dominated by micturition disorder (59%), abdominal or flank pain (28%), nephritic colic (22%), hematuria (22%) and urinary tract infection (13%). Stones were located in the upper urinary tract in 62.5% of cases.Stones were treated by surgery in 89 cases (89%), and with ESWL in only 2 cases (2%).Over these years of study, a prevalence of 0.83% of childhood urolithiasis was calculated.ConclusionsThis preliminary study represents only a region of the country, so more epidemiological analyses should be done.Stone analysis should be performed more frequently, and patients must be presented at earlier stages, before any development of renal failure.     

Recurrent acute kidney injury in elderly patients is common and associated with 1-year mortality

Background

Acute kidney injury (AKI) is common among elderly patients after a first hospitalized AKI. Patients who recover are at risk for recurrence, but recurrent geriatric AKI is not well-studied.

Methods

This was a retrospective, 12-month cohort study using data from the National Clinical Research Center for Geriatric Diseases. Recurrent AKI was defined as a new spontaneous rise of?≥?0.3 mg/dl (≥?26.5 µmol/L) within 48 h or a 50% increase in serum creatinine (Scr) from the baseline within 7 days after the previous AKI episode. The outcome measured was 12-month mortality.

Results

Among 1711 study patients, 652 developed AKI. Of the 429 AKI survivors in whom recovery could be assessed, 314 patients recovered to their baseline renal function, and 115 patients developed chronic kidney disease (CKD). Of the group that recovered renal function, 90 patients (28.7%) subsequently developed recurrent AKI, while 224 (71.3%) did not. Of the 429 survivors with AKI, 103 patients (24.0%) died within 12 months. Multivariate logistic regression analysis revealed that recurrent AKI was significantly associated with coronary disease (odds ratio [OR?=?2.008; 95% confidence interval [CI] 1.024–3.938; P?=?0.042), a need for mechanical ventilation (OR?=?2.265; 95% CI 1.267–4.051; P?=?0.006) and high blood urea nitrogen levels (OR?=?1.036; 95% CI 1.002–1.072; P?=?0.040) at the first AKI event. Kaplan–Meier curves showed the 12-month survival of patients with non-recurrent AKI was better than that of patients with CKD, and survival of patients with recurrent AKI was worse than that of patients with CKD (log rank P?<?0.001). In the multivariate Cox regression analysis, mortality at 12 month was higher in the patient with recurrent AKI as compared with those with a single episode (HR?=?3.375; 95% CI 2.241–5.083; P?<?0.001).

Conclusion

Recurrent AKI is common among elderly patients who recovered their renal function post-AKI and is associated with significantly higher 12-month mortality compared with CKD patients.