Urinary Urobilinogen: An Overlooked Diagnostic Clue in Early Hepatic and Hemolytic Disorders

Abstract

Context: Alterations in urinary urobilinogen levels are frequently encountered in clinical practice but are often overlooked as a diagnostic tool. Evidence Acquisition: This review introduces an innovative clinical approach by emphasizing urobilinogen as an early and underutilized biomarker for hepatic dysfunction and hemolytic disease. Methods: PubMed, Google Scholar, Scopus, and Web of Science were searched to identify relevant articles on urinary urobilinogen, with a focus on its diagnostic value. Studies were selected based on clinical relevance, limited to English-language publications, and excluded non-human or purely experimental research. Results: A comprehensive framework for interpreting urobilinogen alterations is provided, categorizing causes into hepatocellular, cholestatic, and prehepatic conditions. This review integrates urobilinogen assessment into a structured diagnostic approach, aiding clinicians in differentiating between hepatic and prehepatic causes while enhancing early detection strategies. Additionally, its clinical significance in hemolytic conditions, acute hepatic porphyrias, and liver diseases with normal LFTs was highlighted, reinforcing the role of urobilinogen as a sensitive underrecognized marker in hepatology and hematology. This review underscores its potential to improve early disease recognition, optimize patient management, and refine diagnostic pathways in routine medical practice by advocating for urobilinogen testing alongside traditional diagnostics. Conclusions: Unlike conventional liver function tests (LFTs), which may remain normal in early disease stages, urobilinogen levels can indicate subclinical hepatic impairment or compensated hemolysis before overt biochemical abnormalities appear.