Acral subcutaneous steatocystoma multiplex: a distinct subtype of the disease?

Sonographic Appearance of Steatocystoma: An Analysis of 14 Pathologically Confirmed Lesions

Purpose

To evaluate the ultrasonographic characteristics of steatocystomas focusing on the features that aid in differentiating them from epidermal inclusion cysts and lipomas.

Materials and Methods

The ultrasonographic findings of 14 histologically proven steatocystomas in 10 patients were retrospectively reviewed. The following features were assessed: the layer of involvement, shape, margin, echogenicity, posterior acoustic features, and the presence of a visible wall or intralesional striations. The findings were compared with those of subcutaneous lipomas and epidermal inclusion cysts to identify those findings that aid in the differential diagnosis of steatocystomas.

Results

The majority of steatocystomas appeared as a subcutaneous mass (n = 6, 42.9%) or a mass involving both the dermal and subcutaneous layers (n = 6, 42.9%). Steatocystomas exhibited a well-defined smooth margin (n = 12, 85.7%) and homogeneous echogenicity (n = 9, 64.3%), and showed no specific posterior acoustic features (n = 9, 64.3%). The most important features that differentiated steatocystomas from epidermal inclusion cysts were a homogeneous internal echotexture (p = 0.009) and absent or less prominent posterior acoustic enhancement (p < 0.001). The features that distinguished steatocystomas from lipomas were the margin (p < 0.001), echogenicity (p = 0.034), internal echotexture (p = 0.004), and the absence of intralesional striations (p < 0.001).

Conclusion

Steatocystomas appeared as well-defined homogeneous masses with mild or absent posterior acoustic enhancement.

Steatocystoma multiplex: A case report of a rare entity

Steatocystoma multiplex is an uncommon benign skin disease, which typically manifests as numerous intradermal cysts that can be scattered anywhere on the body. Although usually asymptomatic, it can be significantly disfiguring. One type of steatocystoma multiplex is known to be associated with the autosomal dominant inheritance of a mutation in the gene coding for keratin 17 (KRT17). In such cases, it is often concurrent with other developmental abnormalities of the ectoderm-derived tissues, such as the nails, hair, and teeth. To the best of our knowledge, few cases have been reported of steatocystoma multiplex of the oral and maxillofacial region. This report describes a case of steatocystoma multiplex of both sides of the neck and multiple dental anomalies, with a focus on its clinical, radiological, and histopathological characteristics, as well as the possibility that the patient exhibited the familial type of this condition.

Coexistence of steatocystoma multiplex and hidradenitis suppurativa: Assessment of this unique association by means of ultrasonography and Color Doppler

BACKGROUND

Steatocystoma multiplex (SM) is an uncommon skin disease manifesting as multiple sebum-containing cysts arising in pilosebaceous unit-rich body areas. Hidradenitis suppurativa (HS) is a debilitating chronic inflammatory disease affecting the apocrine gland-bearing skin and presenting with both pseudocystic and inflammatory nodules, abscesses and fistulas. Considering that genetics has been reported to play a role in both entities, the albeit rare association between them suggests a shared genetic background. Although histology remains the gold standard for the diagnosis of SM, ultrasonography can be an useful diagnostic tool. This method is largely used in combination with Color Doppler for assessing disease severity in HS.

MATERIALS AND METHODS

We report three cases of coexisting SM and HS and describe the ultrasonography and Color Doppler features of the two entities.

RESULTS

SM lesions appeared on ultrasonography as hypoechoic nodules with well-defined hyperechoic borders and posterior acoustic enhancement, in the absence of Color Doppler signal. HS lesions had the ultrasonographic features of the fistulas, abscesses and pseudocystic nodules, some of which including hair fragments, with an intense Color Doppler signal within or around inflamed lesions.

CONCLUSION

The combination of ultrasonography and Color Doppler proved to be a reliable instrument for differentiating between SM and HS lesions, particularly distinguishing HS pseudocystic nodules from true cysts of SM.

Case Series: A Kindred With Eruptive Vellus Hair Cysts and Systemic Features

Eruptive vellus hair cysts (EVHCs) often occur on the trunk and limbs. Facial involvement is uncommon. Autosomal dominant inheritance has been described, but associated extracutaneous anomalies have not. We describe a 4-patient kindred presenting with multiple facial EVHCs and an association of preauricular pits, lipomas, joint hypermobility, and cardiac defects. Histopathologic examination confirmed the diagnosis of EVHCs in 3 affected individuals. We propose that facial EVHCs may indicate the presence of an inherited autosomal dominant disorder with extracutaneous manifestations. Extracutaneous manifestations noted in the kindred have been sporadically described in association with steatocystoma multiplex (SM), a condition occasionally noted in the presence of EVHCs, further supporting an association between these disorders.