Admission ultrasonography as a predictive tool for thrombocytopenia and disease severity in dengue infection

Background: Ultrasound (US) is an investigation available in many acute care settings. Thrombocytopenia is a well-described complication of dengue infection and has been shown to correlate with disease severity. The purpose of this study was to assess the utility of admission ultrasonography in predicting thrombocytopenia and disease severity in patients infected with dengue virus. Methods: Data were collected prospectively on 176 patients (male, n=86; female, n=90) admitted to the Nawaloka Hospital, Sri Lanka with dengue infection between December 2016 and August 2018. All patients had an US scan on admission and disease severity was determined using the World Health Organization 2009 classification. Results: There were 106 (60.2%) cases of dengue with/without warning signs and 70 (39.8%) cases of severe dengue. Patients with an abnormal US on admission were more likely to have severe dengue. Gallbladder wall thickening was the most common US abnormality. Abnormal US findings significantly correlated with more pronounced thrombocytopenia from day 2 of admission. Conclusions: An abnormal US scan on admission can aid in identification of patients at risk of developing severe dengue and can be used as a novel clinical tool to identify patients at risk of severe thrombocytopenia.