S. Lewis1, C. St. Laurent1, A. Ruiz-Elizalde1 1University Of Oklahoma College Of Medicine,Oklahoma City, OK, USA
Introduction: Appendectomy is one of the most common surgical procedures performed in children. Acute appendicitis is one of the leading pathologies requiring hospitalization in children. Delays in diagnosis of acute appendicitis can be catastrophic and has been proven to directly increase morbidity and mortality in this patient population. Even with advancement in imaging and scoring systems used for diagnosis of acute appendicitis, there are a subset of patients who have a delay in diagnosis resulting in increased hospital stay, operation time, and more invasive surgical procedures. One condition that can share clinical symptoms of acute appendicitis in the pediatric population is urinary tract infection; both can present with abdominal pain, fever, nausea, vomiting, and leukocytosis. With children being less adept to elucidate their specific symptoms, these two diagnoses can easily be included in the differential together. The diagnostic techniques use to clearly delineate these two entities include imaging, whether abdominal CT or ultrasound, and urine analysis (UA). With the deliberate avoidance of ionizing radiation in the pediatric population and ultrasound operator/patient dependent limitations, this can lead to heavy reliance on UA for diagnostic clarity. It has been referenced, that pyuria can be present in the urine of a patient with acute appendicitis, but the statistical percentage of patients has not been defined. The aim of this study was to prove that sterile pyuria is present in a statistically significant number of patients with acute appendicitis and pyuria should be an expected diagnostic finding.
Methods: After IRB approval, a retrospective chart review of all pediatric surgical patients (ages 2-14) who underwent an appendectomy, from January 2015 through December 2017, and had a pre-operative UA was performed. Pyuria was defined as >5 WBC in the urine with sterility defined as negative urine culture or resolution of symptoms without treatment of urinary tract infection.
Results: Of the 219 patients who met inclusion criteria, 52 patients had pyuria (24%). Of these, 31/52 had a urine culture collected at the time of the UA and only 4 (13%) were positive. The other 21 patients did not have urine cultures but had resolution of symptoms status post appendectomy. We therefore found a 25% sterile pyuria rate in our patients who underwent appendectomy as compared to the published rates of sterile pyuria in the general pediatric outpatient population of 9-13%.
Conclusion: Our pediatric patients with appendicitis had a 2 fold increase in the rate of sterile pyuria over the general pediatric outpatient population, which suggests an association between intraabdominal inflammation and sterile pyuria. Pyuria in the presence of abdominal pain, does not always indicate urinary tract infection and providers should keep acute appendicitis high on their list of differential diagnoses.