Kimura's Disease without Peripheral Eosinophilia: An Unusual and Challenging Case Simulating Venous Malformation on Imaging Studies-Case Report and Review of literature

Abstract

Kimura's Disease (KD) is a rare chronic inflammatory disorder presenting as multiple painless solitary subcutaneous nodules, predominantly in the head and neck region and frequently associated with regional lymphadenopathy and/or salivary gland involvement. Because of painless nature and indolent course, there is usually a delay in the patient's presentation. KD may radiologically mimic other chronic inflammatory conditions like tuberculosis, vascular malformations and neoplasms. Clinical correlation and histological evaluation along with elevated peripheral eosinophil and serum IgE level are considered important for confirmatory diagnosis. We report a case of painless swelling over right submandibular region extending to the right superficial parotid. The haematological reports were within normal limits. Ultrasound (USG), Magnetic Resonance Imaging (MRI) and Magnetic Resonance Angiogram (MRA) favoured a diagnosis of venous malformation. However, histopathological examination of excised lesion confirmed a diagnosis of KD. This case proves the possibility of the KD even in the absence of peripheral eosinophilia and/ or elevated serum IgE level, and may mimic venous malformation on imaging studies. Therefore, KD must find a place in the differentials of solitary painless neck swelling even in the absence of peripheral eosinophilia and/or elevated IgE level.

Keywords: Angiolymphoid hyperplasia with eosinophilia; Immunoglobulin E; Subcutaneous nodule.

[Table/Fig-1]:

Right subcutaneous swelling extending from angle of right mandible to right parotid region.

[Table/Fig-2]:

USG with Doppler study neck showing a superficially located mixed echoic lesion over right side neck and extending superiorly over parotid gland. The lesion appeared moderately vascular showing multiple tortuous arterial and venous channels on Doppler.

[Table/Fig-3]:

MRI with T1 and T2 weighted image in axial view showing a right subcutaneous mass (marked by bold red arrows).

[Table/Fig-4]:

MRA showing the lesion draining into external jugular vein

[Table/Fig-5]:

Intraoperative photograph of the lesion being excised.

[Table/Fig-6]:

Excised surgical specimen.

[Table/Fig-7]:

a) photomicrograph showing salivary gland tissue with lymphoid hyperplasia and germinal center formation (H&E 4x); 7b) photomicrograph showing increase in number of blood vessels in the interfollicular area, some of which shows hyalinization (H&E 10x); 7c) photomicrograph showing eosinophilic infiltrate (H&E 40x).