Contrast-enhanced ultrasound (CEUS) in diagnosis of Kikuchi disease: how to distinguish it from lymphoma?

BACKGROUND

Kikuchi disease (KD) typically presents as lymphadenopathy and is easily confounded with lymphoma. This study analyzes the contrast-enhanced ultrasound (CEUS) characteristics of KD for the differentiation from lymphoma. This study aims to delineate the imaging features of KD and differentiate it from lymphoma, avoiding unnecessary core needle biopsy (CNB).

METHODS

A retrospective analysis of the clinical and ultrasound (US) examination data of 60 patients with surgically and pathologically confirmed KD or lymphoma was conducted. The basic characteristics, US, CEUS characteristics were compared between two groups. The univariate and multivariate analyses were used to identify features associated with KD.

RESULTS

A total of 22 KD and 38 lymphoma patients were evaluated in this study, including 26 males and 34 females (mean age 42.92±21.24 years). The age, long diameter (LD), short diameter (SD), perinodal fat hyper-echogenicity, normal echogenic hilus, color Doppler flow images (CDFI) distribution, enhancement margin, enhancement pattern, perfusion defect, numbers of perfusion defect, margin of perfusion defect, percentage of perfusion defect and reticulated enhancement showed statistically significant differences between two groups (P<0.05). Univariate analysis showed that age, LD, SD, normal echogenic hilus, perinodal fat hyper-echogenicity, lymph nodule hilar vascularity, ill-defined enhancement margin, perfusion defect and reticulated enhancement absent were the independent predictors of KD (P<0.05). Multivariate analysis showed that age and SD were independent predictors of KD (P<0.05). The area under the curve (AUC) of age, SD and predicted probability were 0.939 [95% confidence interval (CI): 0.876-1.000], 0.809 (95% CI: 0.702-0.916) and 0.974 (95% CI: 0.938-1.000) respectively.

CONCLUSIONS

Combining with age, size of lymph nodules, US and CEUS features could effectively diagnose KD. KD is characterized by ill-defined enhancement margins and typically presents with a single, small, well-defined perfusion defect on CEUS. A reticulated enhancement is the distinctive CEUS presentation of lymphoma. CEUS could yield more information for further diagnosis.