MATERIALS AND METHODS
Patients hospitalized with diagnosis of Covid-19 between October 2 and
December 25, 2020were enrolled. The diagnosis of Covid-19 was confirmed
with at least one positive real-time reverse transcriptase-polymerase
chain reaction (RT-PCR) test result in cases admitted with symptoms,
signs and findings (laboratory/radiological) suggestive of Covid-19,
according to the national guidelines [13]. We excluded the following
patients; patients who were on regular hemodialysis, pregnant, who were
transferred from intensive care unit (ICU), who had urinary tract
infection or who had uretheral catheters. For patients who had multiple
qualifying hospital admissions, we included only the first
hospitalization however outcomes were recorded according to the last
hospitalization.
The source of medical records was OCTOMED (Kartal Dr.Lutfi Kirdar City
Hospital Automation Program) electronic database system. The National
Public Health Data Management System database was also used as an
external data source, particularly to track the RT-PCR test results and
to obtain data on previous creatinine values. We collected data for
patient demographics, comorbidities, vital signs and laboratory test
results on admission. Laboratory data consisted of measurements of white
blood cell (WBC), lymphocyte, hemoglobin (Hb), platelet count (PLT),
serum glucose, urea, creatinine (SCr), albumin, sodium, potassium,
chloride, calcium, aspartate aminotransferase (AST), alanine
aminotransferase (ALT), lactate dehydrogenase (LDH), C-reactive protein
(CRP), ferritin, fibrinogen, D-dimer and creatinine kinase (CK)
levels.The first value of laboratory data within 48 hours of hospital
admission was taken. Additionally, peak and discharge creatinine values
were also collected. IL-6 was taken once as the highest value during
hospitalization. Furthermore, medications used for the treatment of
Covid-19 were also recorded.
We additionally collected urinalysis with automated microscopy that were
obtained within 48 hours after admission. The urine samples were
collected in containers, transported and analysed within 2 h of
collection. The analyses were carried out on H-800 and FUS-200 automatic
modular urine analysers (Dirui Industry, Changchun, China). A further
microscopic analysis of sediments was performed, if required.
Outcomes data were retrieved until January 10, 2020. By the time of this
analysis, all patients had either died or had been discharged from the
hospital. The primary outcome was the development of AKI and secondary
outcome was in-hospital mortality.