Introduction: Urinalysis is commonly performed in the United States. We critically evaluated urinalysis indications in the United States.
Methods: We obtained an Institutional Review Board exemption for this study. 2015 National Ambulatory Medical Care Survey data were queried for urinalysis testing frequency and associated International Classification of Diseases, ninth edition diagnoses. 2018 MarketScan data were queried for urinalysis testing frequency and associated International Classification of Diseases, 10th edition diagnoses. We considered International Classification of Diseases, ninth edition codes for genitourinary disease, diabetes, hypertension, hyperparathyroidism, renal artery disease, substance abuse, or pregnancy as an appropriate indication for urinalysis. We considered International Classification of Diseases, 10th edition codes A (certain infections and parasitic diseases), C, D (neoplasms), E (endocrine, nutritional, and metabolic diseases), N (disease of the genitourinary system), and select R codes (symptoms, signs, and abnormal clinical laboratory findings, not elsewhere classified) as an appropriate indication for urinalysis.
Results: Of 99 million 2015 urinalysis encounters, 58.5% had an International Classification of Diseases, ninth edition code for genitourinary disease, diabetes, hypertension, hyperparathyroidism, renal artery disease, substance abuse, and pregnancy. Forty percent of the 2018 urinalysis encounters did not have an International Classification of Diseases, 10th edition diagnosis. Twenty-seven percent had an appropriate primary diagnosis code, and 51% had one of the appropriate codes. The most common International Classification of Diseases, 10th edition codes were encounter for general adult examination, urinary tract infection, essential hypertension, dysuria, unspecified abdominal pain, and encounter for general adult medical examination with abnormal findings.
Conclusions: Urinalysis is commonly performed without an appropriate diagnosis. Widespread urinalysis leads to a large number of evaluations for asymptomatic microhematuria, with associated cost and morbidity. Closer examination for urinalysis indications is needed to reduce costs and morbidity.
Keywords: urinalysis, hematuria.