The role of cystatin C and various methods of glomerular filtration rate calculation in evaluation of renal dysfunction in children with acute infectious diarrhea

Rationale: Acute infectious diarrhea (AID) is the fourth leading cause of death among children <5 years worldwide. Kidney damage is one of the poorly studied aspects of pediatric AID. The level of serum cystatin C is independent on gender and age, and it is highly informative even in the early stages of renal dysfunction.Aim: To optimize diagnosis of renal dysfunction in children with moderate AID through comparison of different methods of glomerular filtration rate (GFR) calculation and determination of serum cystatin C level.Materials and methods: Observational cross-sectional study enrolled 80 children in pediatric hospital with moderate AID not followed by hemolytic uremic syndrome. Serum creatinine and serum cystatin C levels were determined in all the patients in acute period with GFR calculating according to Schwartz equation in unmodified (1976) and modified (2009) versions. GFR was also calculated using a single-factor equation based on serum cystatin C level.Results: GFR in acute period, calculated according to unmodified and to modified Schwartz equation was in patients <3 years (n=40) 115.47±3.33 ml/min/1.73 m2 and 98.56±2.84 ml/min/1.73 m2 (p<0.001), in patients 3–7 years 132.13±4.2 ml/min/1.73 m2 and 108.85±3.84 ml/min/1.73 m2 (p<0.001), respectively. Increased serum cystatin C level (>950 ng/ml) occurred in 18 patients (22%). In other patients level of serum cystatin C remained within the reference range or lower. The risk of acute kidney injury development based on two indicators – GFR according to the modified Schwartz equation and GFR according to the equation used cystatin C level – occurred in 4 (10%) patients aged 1–3 years and in 1 (2.5%) child in the age group 3–7 years; risk, based on one indicator – the calculation of GFR according to the formula using cystatin C – in 8 (20%) and 9 (22.5%) children, respectively, and based on the assessment of only GFR according to the modified Schwartz equation – in 3 (7.5%) children of both age groups.Conclusion: We have confirmed that the GFR values calculated with usage of unmodified Schwartz equation (1976) are higher than those calculated with usage of modified Schwartz equation (2009) and taking into account the level of cystatin C. Thus, usage of unmodified Schwartz equation for GFR calculation in infants and preschool children seems incorrect. Level of serum cystatin C is promising marker permitted to select patients with risk of acute kidney injury development among children in acute period of moderate AID.

Creation and Validation of a Pediatric Vancomycin Nomogram for a Goal Trough of 10–15 mg/L at a Quaternary Care Children’s Hospital

Background Recent data suggest a serum vancomycin (vanc) trough (VT) of 11mg/L correlates with an AUC/MIC24 &gt; 400 which has shown to be the optimal concentration to eradicate MRSA infection and improve mortality. There are currently limited published recommendations on how to achieve such a VT in children. This study validates a vancomycin nomogram used to achieve a VT of 10–15 mg/L in pediatric inpatients (pts) at a quaternary care children’s hospital. Methods This is an 18 month (mo) prospective analysis beginning in September 2015. Included pts were ≥2 mo of age and had ≥2 consecutive VT. Pts receiving renal replacement therapy or those with a serum creatinine (Scr) of ≥0.5 mg/dL from a prior admission or within 48 hours of vanc initiation were excluded. The starting dose (SD) of vanc was determined by age and creatinine clearance (CrCl) (Tables 1 and 2). CrCl was measured by Bedside Schwartz equation for patients ≤18 years old (yo) and Cockcroft-Gault equation for patients &gt;18 yo. The maximum CrCl was set to 120 ml/minute. Patients who were on vanc and experienced a Scr increase of ≥0.5 mg/dL were considered to have acute kidney injury (AKI). The study had a 6 mo evaluation period which led to a revised version (RVN) on March 2016. The primary endpoint (PE) was achievement of 10–15 mg/L by the Second VT for patients with the First trough outside of this range, using our RVN (Table 3). Results Overall, a total of 276 patients received vanc, 17 and 29 patients were dosed according to the initial and RVN, respectively. For young children (Table 1), the SD for patients with a CrCL ≥90 ml/minute was therapeutic, sub-, and supra-therapeutic in 43.75%, 47.5% and 8.75%, respectively. For older children (Table 2), the SD for patients with a CrCl ≥100 ml/minute was therapeutic, sub-, and supra-therapeutic in 41.1%, 35.7% and 23.2%, respectively. The initial VN was successful 12/17 (70.6%) in achieving the PE. Success in achieving the PE after the RVN was 26/29 (89.7%). In the RVN group, the most common initial troughs were 5–7 mg/L (33.3%), followed by &gt;18 mg/L (27.6%). The mean VT using the RVN was 13.7 mg/L. The overall AKI incidence throughout the study was 3.2% (9/276) and 0% using the RVN. Conclusion Our RVN led to a Second VT within a target range of 10–15 mg/L for 89.7% of patients, allowing for more accurate and safer use of vancomycin in our institution. Disclosures All authors: No reported disclosures.

Efficient reporting of the estimated glomerular filtration rate without height in pediatric patients with cancer

Background:The updated bedside Schwartz equation requires constant, serum creatinine concentration and height measurements to calculate the estimated glomerular filtration rate (eGFR) in pediatric patients. Unlike the serum creatinine levels, obtaining height information from the laboratory information system (LIS) is not always possible in a clinical laboratory. Recently, the height-independent eGFR equation, the full age spectrum (FAS) equation, has been introduced. We evaluated the performance of height-independent eGFR equation in Korean children with cancer.Methods:A total of 250 children who underwent chromium-51-ethylenediamine tetra acetic-acid (Results:The FAS equation showed significantly lower bias (mL/min/1.73 mConclusions:The height-independent eGFR-FAS equation was less biased and as accurate as the updated Schwartz equation in Korean children. The use of the height-independent eGFR equation will allow for efficient reporting of eGFR through the LIS in clinical laboratories.