Acoustic radiation force impulse imaging of biopsy-proven Kikuchi disease: initial experiences for evaluating feasibility in pediatric patients

Can Shear Wave Elastography Help Differentiate Acute Tonsillitis from Normal Tonsils in Pediatric Patients: A Prospective Preliminary Study

Shear wave elastography (SWE) is a non-invasive imaging technique used to quantify the elasticity/stiffness of any tissue. There are normative SWE studies on tonsils in healthy children in the literature. The purpose of this study is to analyze the palatine tonsils in children with acute tonsillitis using ultrasound and SWE. In this prospective study, pediatric patients aged 4-18 years diagnosed with acute tonsillitis and healthy children were included. Those with antibiotic use, chronic tonsillitis, adenoid hypertrophy, and having chronic disease, immunodeficiency, and autoimmune disease, or any rheumatological disease were excluded. The volume and elasticity of palatine tonsil were measured via ultrasound and SWE. The study included 81 (46 female, 35 male) acute tonsillitis patients, and 63 (38 female, 25 male) healthy children between the ages of 4 and 18. Elasticity (kPa) values of tonsils were found significantly higher in the tonsillitis group (SWE-R: 25.39 ± 4.64, SWE-L: 25.01 ± 4.17) compared to the normal group (SWE-R: 9.71 ± 2.37, SWE-L: 9.39 ± 2.19) (p < 0.001). In the tonsillitis group, a significant positive correlation was found between tonsil volume and elasticity (r: 0.774, p: 0.002). In conclusion, in pediatric patients with acute tonsillitis, higher kPa values were obtained with SWE in the palatine tonsils.

Kikuchi Cervical Lymphadenitis in Children: Ultrasound Differentiation From Common Infectious Lymphadenitis

OBJECTIVES

To investigate ultrasound (US) features of enlarged cervical lymph nodes (LNs) to differentiate between Kikuchi disease (KD) and other common types of infectious lymphadenitis in an East Asian pediatric patient population.

METHODS

A total of 142 pediatric patients with KD and 45 patients with infectious lymphadenitis (suppurative lymphadenitis [n = 29], nontuberculous mycobacterial lymphadenitis [n = 9], and tuberculous lymphadenitis [n = 7]) were included. The clinical characteristics, laboratory results, and US features of LNs were reviewed. The area under the curve (AUC) from a receiver operating characteristic curve analysis was used as a diagnostic accuracy measure.

RESULTS

A multiple clustered adjacent pattern, bilaterality, an even size, posterior neck involvement, no enlargement, an elongated-to-ovoid shape, homogeneous hypoechogenicity, a well-defined margin, presence of an echogenic fatty hilum, no intranodal gross necrosis, increased perinodal fat echogenicity, and no increased echogenicity of the adjacent sternocleidomastoid muscle were significant US features of the affected LNs to discriminate KD from infectious lymphadenitis (P < .05). Homogeneous hypoechogenicity in KD showed the highest AUC (0.930) as a single variable (95% confidence interval, 0.88-0.96). The AUCs were increased in 3 combination models with 2 US features: homogeneous echogenicity and 1 of 3 other US features (increased perinodal fat echogenicity, 0.935; number of affected LNs, 0.947; and LN shape, 0.949).

CONCLUSIONS

Homogeneous hypoechogenicity of LNs was a significant US feature with the highest diagnostic accuracy in differentiating KD from common infectious lymphadenitis on a univariate analysis. In the combination model, US features of an elongated-to-ovoid shape and homogeneous hypoechogenicity showed the highest diagnostic accuracy.

Kikuchi-Fujimoto Disease: A Rare Cause of Cervical Lymphadenopathy

Kikuchi-Fujimoto disease (KFD) is a rare benign disease, clinically characterized by fever and tender cervical lymphadenopathy affecting the posterior cervical lymph nodes. This disease is usually accompanied by night sweats, rashes, and headaches. It generally affects young individuals, especially females, of Oriental-Asian origin. The etiology of KFD remains uncertain, but associations have been noted with viral diseases including Epstein-Barr virus (EBV), herpes simplex virus (HSV), and varicella-zoster virus (VZV), as well as autoimmune disorders including systemic lupus erythematosus (SLE) and Sjogren's syndrome. This review points out the etiology of KFD with cervical lymphadenopathy alongside its clinical presentation, histological highlights, lab investigations, complications, and treatment. Accurate diagnosis of this disease depends on lymph node excisional biopsy. Three histological patterns of KFD are recognized: proliferative, necrotizing, and xanthomatous. Distinction from lymphadenopathy-associated alternate disorders (e.g., SLE, malignancy, tuberculosis, or another infectious lymphadenitis) is essential to ensure appropriate therapy. This self-limited condition entails nonsteroidal anti-inflammatory drugs (NSAIDs) for pain relief with consideration of corticosteroids and hydroxychloroquine in severe cases.

Evaluating Lymph Node Stiffness to Differentiate Bacterial Cervical Lymphadenitis and Lymph Node-First Presentation of Kawasaki Disease by Shear Wave Elastography

OBJECTIVES

The purpose of our study was to evaluate the potential of cervical lymph node shear wave elastography (SWE) to quantify the lymph node stiffness (kilopascals) noninvasively among patients with lymph node-first presentation of Kawasaki disease (NFKD), patients with bacterial cervical lymphadenitis (BCL), and healthy children (HC). We further aimed to investigate the correlation of laboratory data and lymph node stiffness to provide a reference basis for the early diagnosis of NFKD.

METHODS

Lymph node stiffness measurements were prospectively performed in 47 patients with NFKD, 56 patients with BCL, and 56 HC using SWE. Cervical SWE was compared in the groups. Factors associated with increased cervical lymph node stiffness were studied.

RESULTS

The mean elasticity of the largest cervical lymph nodes was significantly higher in the BCL group than the NFKD and HC groups (mean elasticity ± SD, 16.37 ± 2.45, 12.22 ± 2.64, and 7.81 ± 1.67 kPa, respectively; P < .01), with a cutoff of 14.55 kPa (area under the curve, 0.885; sensitivity, 89%; and specificity, 76%). In patients with NFKD, interleukin 6 (standardized β = 0.363; P = .01), alanine aminotransferase (standardized β = 0.253; P = .03), aspartate aminotransaminase (standardized β = 0.536; P = .047), and total bilirubin (standardized β = 0.486; P < .01) values were correlated with increased largest cervical lymph node stiffness.

CONCLUSIONS

Cervical lymph node stiffness was different between NFKD and BCL. Shear wave elastography is a potential method to identify clinically distinguishable early NFKD.