Necrotizing (Abscessing) Lymphadenopathy and the Diagnostic Value of Contrast-Enhanced Ultrasound (CEUS): A Review with Clinical Vignettes.

Necrotizing (abscessing) lymphadenopathy is a clinically relevant condition with a broad differential diagnosis, including acute bacterial infections, mycobacterial disease, zoonoses, fungal and parasitic infections, autoimmune disorders, and malignancies with central necrosis. Early and reliable differentiation between these causes is important to avoid misdiagnosis and to guide appropriate therapy. This review summarizes the pathophysiological mechanisms, typical imaging features, and diagnostic value of contrast-enhanced ultrasound (CEUS) in necrotizing lymphadenopathy. Representative clinical vignettes illustrate the disease spectrum and correlate CEUS patterns with underlying pathology. The literature review was narrative and based on targeted searches of PubMed/MEDLINE and Google Scholar focusing on CEUS in necrotizing lymphadenopathy. A brief literature overview highlights current evidence, limitations, and research gaps. Conventional B-mode ultrasound (BMUS) and Doppler typically demonstrate enlarged hypoechoic or heterogeneous nodes with reduced central vascularity but lack specificity for necrosis. CEUS provides real-time visualization of nodal microvascular perfusion, which may support clearer differentiation between viable tissue and necrotic or abscess cavities. Common but non-specific CEUS patterns include central non-enhancement with a peripheral hyperemic rim in abscesses, irregular avascular cores in tuberculous lymphadenopathy, patchy non-enhancing areas in autoimmune conditions, and heterogeneous enhancement with ill-defined necrosis in malignant nodes. CEUS can support biopsy targeting, facilitate drainage procedures, and enable radiation-free follow-up. CEUS may offer diagnostic and interventional advantages in the evaluation of necrotizing lymphadenopathy, offering more consistent characterization of nodal necrosis compared with conventional sonography. While most evidence focuses on tuberculosis and malignancy, growing experience with zoonotic and autoimmune diseases suggests broader utility. Most currently available evidence derives from observational studies and small case series, highlighting the need for prospective multicenter validation. Standardization of CEUS criteria, integration into multiparametric ultrasound protocols, and multicenter validation are needed to establish CEUS as a routine component in the diagnostic work-up of necrotizing lymphadenopathy.