title: Decreased Cystatin C-Estimated Glomerular Filtration Rate Is Correlated with Prolonged Hospital Stay in Transient Tachypnea of Newborn Infants.
abstract: Transient tachypnea of the newborn (TTN) is a benign disorder with a variable clinical course that often leads to hospitalization. The aim of this study was to assess and validate the relationship between the serum cystatin C level and symptom duration in infants with TTN.
  
  
  
  Forty newborns presenting with TTN and who had undergone serum cystatin C (Cys C) tests on the first day of admission to the Kyung Hee University Hospital (Seoul, Korea) from 2009 to 2013 were included. The serum Cys C level, creatinine (Cr) level, estimated glomerular filtration rate (eGFR), and tachypnea duration were correlated retrospectively.
  
  
  
  The median gestation period was 37.8 ± 3.8 weeks and the mean birth weight was 3.2 ± 0.4 kg. Tachypnea duration was 3.3 ± 2.0 days. Serum Cys C and Cr levels were 1.7 ± 0.2 mg/L and 0.8 ± 1.2 mg/dL, respectively. Tachypnea duration was significantly positively correlated with the serum levels of Cys C and significantly negatively correlated with Cys C-based eGFR (p = 0.016), but was not significantly correlated with the serum Cr level or Cr-based eGFR. When tachypnea duration was compared between infants with Cys C level <1.6 mg/L (n = 15; Group A) and infants with Cys C level ≥ 1.6 mg/L (n = 25; Group B), the symptom duration was significantly shorter in Group A infants (p = 0.011).
  
  
  
  Tachypnea duration was shorter with higher Cys C-based eGFR in infants with TTN.
authors.affiliation: Department of Pediatrics, Kyung Hee University School of Medicine, Seoul, South Korea.
authors.forename: Bo Bae
authors.initials: BB
authors.lastname: Kim
authors.affiliation: Department of Pediatrics, Kyung Hee University School of Medicine, Seoul, South Korea.
authors.forename: Sung-Hoon
authors.initials: SH
authors.lastname: Chung
authors.affiliation: Department of Pediatrics, Kyung Hee University School of Medicine, Seoul, South Korea.
authors.forename: Hoi-Soo
authors.initials: HS
authors.lastname: Yoon
authors.affiliation: Department of Pediatrics, School of Medicine, Seoul Hospital, Soon Chun Hyang University, Seoul, South Korea.
authors.forename: Won-Ho
authors.initials: WH
authors.lastname: Hahn
authors.affiliation: Department of Pediatrics, Kyung Hee University School of Medicine, Seoul, South Korea.
authors.forename: Chong-Woo
authors.initials: CW
authors.lastname: Bae
authors.affiliation: Department of Pediatrics, Kyung Hee University School of Medicine, Seoul, South Korea. Electronic address: feelhope@khu.ac.kr.
authors.forename: Yong-Sung
authors.initials: YS
authors.lastname: Choi
mesh_terms: D015415:Biomarkers / Q000097:blood; D003404:Creatinine / Q000097:blood; D055316:Cystatin C / Q000097:blood*; D005260:Female; D005919:Glomerular Filtration Rate; D006801:Humans; D007231:Infant, Newborn; D007902:Length of Stay; D008297:Male; D056910:Republic of Korea / Q000453:epidemiology; D012189:Retrospective Studies; D013997:Time Factors; D059245:Transient Tachypnea of the Newborn / Q000453:epidemiology
chemical_list: D015415:Biomarkers; D055316:Cystatin C; D003404:Creatinine
keywords: cystatin C; glomerular filtration rate; transient tachypnea of the newborn