ESPN 54th Annual Meeting

ESPN 2022


 
KIDNEY DYSFUNCTION IN MEDICALLY STABLE ADOLESCENTS WITH EATING DISORDERS AND THE VALUE OF CYSTATIN-C
AYSE BILGE BAKLACI 1 NURAY KANBUR 2 BERNA OGUZ 3 FILIZ AKBIYIK 4 MELIS PEHLIVANTURK KIZILKAN 2 SINEM AKGUL 2 ORHAN DERMAN 2 ERCAN AYAZ 3 MITHAT HALILOGLU 3 REZAN TOPALOGLU 5 ALI DUZOVA 5

1- Department of Pediatrics, Hacettepe University Faculty of Medicine, Ankara, TURKEY
2- Division of Adolescent Medicine, Hacettepe University Faculty of Medicine, Ankara, TURKEY
3- Department of Radiology, Hacettepe University Faculty of Medicine, Ankara, TURKEY
4- Ankara City Hospital Siemens Healthineers Laboratory, Ankara, TURKEY
5- Division of Pediatric Nephrology, Hacettepe University Faculty of Medicine, Ankara, TURKEY
 
Introduction:

Eating disorders may cause renal complications. Creatinine measurement may be misleading due to loss of muscle mass in this group of patients. We aimed to determine the frequency of kidney dysfunction, and to evaluate the value of cystatin-C in adolescents with eating disorders.

Material and methods:

Medically stable but not weight restored 41 patients (36 female, 5 male; mean age 15.93 ± 1.47 years; mean follow-up time 12.1±12.3 months) with anorexia nervosa or bulimia nervosa according to DSM-5 at our tertiary referral center, between January 2020 and August 2020, were included. Serum biochemistry markers, serum cystatin-C, complete blood count, urinalysis, urinary protein and electrolytes, estimated glomerular filtration rate (eGFR), 24-hour ambulatory blood pressure (BP) monitorization (ABPM), and renal ultrasonography were evaluated in all patients. An age and sex matched control group was composed for serum creatinine and cystatin-C measurements.

Results:

Microalbuminuria, macroalbuminuria, hypostenuria, leukocyturia (sterile), and hypercalciuria was seen in 19.4%, 2.8%, 32.5%, 7.5%, and 15.8% of cases, respectively. Although serum creatinine levels were comparable to control, serum cystatin-C levels were found to be significantly lower; eGFR values, calculated with different creatinine and/or cystatin-C based methods, showed that 0-9.8% of patients had an eGFR <90 ml/min/1.73m2. Ultrasonographic examination did not reveal nephrolithiasis or nephrocalcinosis. 24-hour ABPM showed that BP levels were significantly low; more remarkable for systolic BP (SBP) and during daytime (31.3% had daytime SBP <5th percentile).

Conclusions:

Cystatin-C may also have limitations for the evaluation of kidney functions due to decreased adipose tissue in patients with eating disorders. There were significant inconsistencies between different creatinine and cystatin-C based eGFR methods.  ABPM may be useful in addition to routine laboratory tests. Longitudinal studies are needed to determine the values of these methods in the management of adolescents with eating disorders.