Background: Gastrointestinal infections (GI) and urological infections (UI) have not been fully addressed in COVID-19 patients. We aimed to evaluate the values of routine fecal occult blood (FOB) test and urinary cytology test (UCT) for screening of GI and UI in COVID-19 patients.
Methods: In this retrospective study, COVID-19 patients without associated comorbidities were divided into FOB- or UCT-positive or FOB- or UCT-negative groups. Their clinical characteristics and laboratory findings were then compared.
Results: A total of 13.6% of patients (47 of 345) tested positive for FOB, and 57.4% (27 of 47) of these patients lacked gastrointestinal symptoms. A total of 30.1% of patients (104 of 345) exhibited gastrointestinal symptoms, and 38.0% (131 of 345) were positive for either FOB or gastrointestinal symptoms. FOB-positive patients possessed significantly higher levels of C-reactive protein and fewer lymphocytes than FOB-negative patients. A total of 36.9% of patients (80 of 217) exhibited positive UCT, and 97.5% (78 of 80) of these patients possessed normal levels of serum markers for renal injuries. Significant differences in age and sex ratios were observed between the UCT-positive and UCT-negative groups, and 72.4% (42 of 58) of female patients over 60 years old were UCT-positive.
Conclusions: Fecal occult blood test in combination with gastrointestinal symptoms could serve as a simple and useful screening approach for GI diagnoses for COVID-19. Age and sex are risk factors for UI in COVID-19 patients. UCT could be a sensitive tool for assessing early UI at a stage in which serum markers for renal injuries appear normal.
Keywords: COVID-19; fecal occult blood test; gastrointestinal infection; urinary cytology test; urological infection.
© 2020 The Authors. Journal of Clinical Laboratory Analysis Published by Wiley Periodicals LLC.