Pyoderma Vegetans Differential Diagnoses

Updated: Apr 06, 2020
  • Author: Robert A Schwartz, MD, MPH; Chief Editor: Dirk M Elston, MD  more...
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Diagnostic Considerations

Pyoderma vegetans may resemble and needs to be distinguished from cicatricial pemphigoid vegetans [25] and from localized pemphigus vegetans, which may be seen lacking mucosal lesions. [26] The large verrucous plaques of pyoderma vegetans may also suggest verrucous carcinoma. [27]

Pyoderma vegetans mimics deep fungal infections at clinical examination. As a result of this clinical resemblance, pyoderma vegetans has been labeled both mycosislike pyoderma and blastomycosislike pyoderma. North American blastomycosis and pemphigus vegetans, a rare variant of the autoimmune disorder pemphigus vulgaris, also clinically resemble pyoderma vegetans. Rarely, other deep fungal infections, including phycomycosis and coccidioidomycosis, mimic the presentation of pyoderma vegetans.

Botryomycosis, a rare bacterial infection, may present similarly to a fungal infection and may appear similar to pyoderma vegetans. Cutaneous botryomycosis is differentiated by the presence of basophilic granules that resemble the sulfur granules of actinomyces at histologic examination. [28] Depressed immunity is also common to cutaneous botryomycosis, as seen in acquired immunodeficiency syndrome (AIDS). [29, 30] In 1995, Marschalko et al suggested that cutaneous botryomycosis is a subtype of pyoderma vegetans, and they proposed that pyoderma vegetans and cutaneous botryomycosis should be classified together. [31]

Bromoderma, mycobacterial infections, and giant keratoacanthomas are also included in the differential diagnosis.

On the penis, it must be distinguished from penile cancer. [24]

Pyodermatitis-pyostomatitis vegetans, a rare mucocutaneous inflammatory disorder evident as vesicular, pustular, exudative, and vegetating plaques and frequently associated with ulcerative colitis, may require distinction. [32, 33] The inflammatory bowel disease may be asymptomatic. [34]  Pyodermatitis pyostomatitis vegetans may be viewed as an oral variant of pyoderma vegetans.

It should be distinguished also from pyoderma gangrenosum. [35]

Necrobiosis lipoidica with seeming progression to pyoderma vegetans was described, perhaps a coincidental association. [36]

Differential Diagnoses