Angiolymphoid hyperplasia with eosinophilia vs. Kimura's disease

Differential Diagnosis

Angiolymphoid hyperplasia with eosinophilia Kimura's disease 1. Does not usually resemble lymphoid tissue when viewed at scanning magnification 1. Resembles lymphoid tissue when viewed at scanning magnification 2. Few lymphoid follicles; sometimes none 2. Many lymphoid follicles 3. A disorder of blood vessels fundamentally 3. A disorder of inflammatory cells (lymphoid follicles) basically 4. Very widely dilated, abnormal, vein-like structures in the dermis and/or subcutaneous fat 4. No very widely dilated, abnormal vascular structures 5. Smooth muscle in the wall of vein-like structures often 5. No smooth muscles in the wall of vessels 6. Abundant mucin in the wall of vein-like structures 6. No mucin in the wall of vessels 7. Plump endothelial cells, some of them polygonal, protrude far into the lumen of vessels 7. Plump endothelial cells do not protrude far into the lumen of vessels 8. One or more vacuoles in the cytoplasm of abnormal endothelial cells common 8. No vacuoles in endothelial cells 9. Eosinophils range in number from absent to numerous 9. Eosinophils countless always 10. Subcutaneous fat not replaced by fibrous tissue 10. Subcutaneous fat often replaced largely by fibrous tissue often 11. No extension to fascia 11. Extension to fascia and sometimes into skeletal muscle

Discussion

For many years, authors of publications in English used the terms "Kimura's disease" and "angiolymphoid hyperplasia with eosinophilia" as synonyms. In truth, these two diseases are different in nearly every respect and they are unrelated entirely to one another. Contrasting them in a work devoted to differential diagnosis in dermatopathology is justified because of several attributes that they share and the common misperception that they are the same disease.

Angiolymphoid hyperplasia with eosinophilia and Kimura's disease have the following findings histopathologic in common: both may involve the dermis and the subcutaneous fat, have infiltrates composed of lymphocytes and eosinophils, possess vessels lined by endothelial cells that may be plump and contain abundant cytoplasm, display fibroplasia, exhibit many plasma cells, and spare epithelial and non-epithelial structures of adnexa. Despite these elements in common, angiolymphoid hyperplasia with eosinophilia and Kimura's disease are distinguished easily from one another at scanning magnification. Angiolymphoid hyperplasia with eosinophilia is typified by very widely dilated, sometimes bizarre-shaped, endothelium-lined spaces lined by plump cells that protrude well into lumina, and those vessels often house smooth muscle and are surrounded by a rim of fibroplasia in company with is abundant mucin. In contrast, Kimura's disease is characterized by a nodular and diffuse infiltration throughout the dermis and well below it dominated by lymphoid follicles in conjunction with fibroplasia that tends to replaces much of the subcutaneous fat. Blood vessels are not abnormal strikingly. At higher magnifications, angiolymphoid hyperplasia with eosinophilia is seen to consist of large, often polygonal endothelial cells, many of which have prominent vacuoles in their cytoplasm. No such vacuoles are present in the endothelial cells of Kimura's disease. Although eosinophils are present usually in both diseases, they may be relatively few, or absent, in angiolymphoid hyperplasia, but they are myriad in Kimura's disease. Last, whereas lymphoid follicles are the sine qua non for diagnosis of Kimura's disease, they are present in fewer than 10% of lesions of angiolymphoid hyperplasia.

Although there are similarities clinical between angiolymphoid hyperplasia and Kimura's disease, there also are many differences between them. For example, both conditions affect men mostly and lesions themselves may be nodules, involve the head and neck primarily, and are given persist. Whereas lesions of Kimura's disease are skin-colored subcutaneous nodules and tumors, those of angiolymphoid hyperplasia are red and purple nodules, the color of them being a manifestation of the basic vascular nature of the process. Angiolymphoid hyperplasia has predilection for ears or the immediate vicinity of them, whereas Kimura's disease has no such inclination, but may present itself as mammoth swelling of one side of the face.

Angiolymphoid hyperplasia is a vascular malformation that results from an underlying arterial-venous shunt. The process is vascular essentially and other changes, such as the presence of lymphoid follicles and eosinophils, seem to be secondary. In contrast, Kimura's disease is thought to have an immunologic basis, as is reflected by the innumerable lymphoid follicles with germinal centers and countless eosinophils.

In sum, the well-ingrained notion that angiolymphoid hyperplasia and Kimura's disease are one and the same disease is not substantiated by data clinical, histopathologic, and biologic. Histopathologically, the two diseases can be differentiated readily from one another at scanning magnification, and other telling differences are found at higher magnifications. In short, angiolymphoid hyperplasia and Kimura's disease are two wholly different, unrelated conditions. Both, however, may be regarded as being distinctive patterns histopathologic: the vascular changes characteristic of angiolymphoid hyperplasia may be encountered episodically as a component incidental to another process pathologic (those changes having been designated, badly, "histiocytoid hemangioma") and the presence of lymphoid follicles is not unique to Kimura's disease; they may be met with in such disparate circumstances as a response to the "bite" of a tick and in angiolymphoid hyperplasia with eosinophilia.

Ref:

Differential Diagnosis In Dermatopathology I, Ii, Iii, Iv.chm