Diagnostic ultrasound patterns of parotid glands in human immunodeficiency virus-positive patients in Mulago, Uganda

Abstract

The purpose of this study was to determine sonographically, in parotid glands of human immunodeficiency virus-positive patients, the condition of glands with or without enlargement, and propose a classification system for the patterns observed using diagnostic ultrasound imaging. In this prospective clinical study, ultrasound scans were performed on 200 patients aged 4-62 years at Mulago Hospital, Uganda. There were four main distinct ultrasound pathological patterns in the parotids, i.e. lymphocytic aggregations (LAs), lymphoepithelial cysts (LECs), fatty infiltration (FI) and lymphadenopathy only. There were additional subdivisions depending on the presence of echogenic foci and intraparotid lymphadenopathy. Of those patients (n = 64) without parotid enlargement, only 8% showed normal ultrasound features, whereas 34% showed LECs and 31% showed LAs. Of those (n = 136) with parotid enlargement, 46% showed LECs, 23% showed FI and 15% showed LAs. The overall prevalence of LECs in the study sample was 42%. LECs were multiple, mainly between 7 mm and 12 mm in diameter and 26% showed internal echogenic foci either mobile or stationary. In contrast, LAs tended to be ill-defined, less than 5 mm and were not associated with posterior acoustic enhancement. Features differentiating LAs from LECs have not been previously described. Parotid FI (lipodystrophy) was noted in patients on highly active antiretroviral therapy, who showed lesser prevalence of LECs after 12 months of treatment. Our study of 200 patients is probably the largest such study in the English language literature. The wide spectrum of diagnostic ultrasound patterns was categorized into four main groups (ten subgroups).