Congenital smooth muscle hamartoma
| Congenital smooth muscle hamartoma | |
|---|---|
| Other names | CSMH |
| Specialty | Dermatology |
Congenital smooth muscle hamartoma is typically a skin colored or lightly pigmented patch or plaque with hypertrichosis.[1]: 627 [2] Congenital smooth muscle hamartoma was originally reported in 1969 by Sourreil et al.[3]
Signs and symptoms
Although the clinical presentation of congenital smooth muscle hamartoma varies, it typically takes the form of an irregularly shaped, skin-colored, or slightly hyperpigmented patch or plaque on the trunk or extremities that is accompanied by noticeable vellus hairs. Often, it is located in the lumbosacral region.[4]
Causes
Congenital smooth muscle hamartoma most likely arises from an abnormal development that occurs during mesodermal maturation, primarily in the arrector pili muscle.[5] It is hypothesized that hypertrichosis results from the CD34 + dermal dendritic cells in the hamartoma stimulating the bulge's epithelial cells.[6]
There have been reports of familial cases recently, which raise the possibility of a genetic susceptibility.[7]
Rarely do diffuse forms of congenital smooth cell hamartoma cause the skin to fold.[5] It may indicate systemic involvement and is described as a symptom of the Michelin tire infant syndrome.[8]
Diagnosis
Histologically, the main characteristics of CSMH include reticular dermal smooth muscle hyperplasia with differently orientated, clearly defined bundles of smooth muscle[9][10] that may extend into subcutaneous adipose tissue. Hair follicles and smooth muscle proliferation are frequently tightly related.[11] Increased epidermal pigment is a sign of hyperpigmentation.[9][10] Immunohistochemical methods have recently clarified a few CSMH markers. It has been observed that CD34-positive dermal dendritic cells are an inherent component of smooth muscle hamartomas.[6] Furthermore, to distinguish clearly between skin cancers of myofibroblastic or fibroblastic origin and spindled smooth muscle cell soft tissue tumors, the cytoskeletal protein h-caldesmon has been employed as a smooth muscle cell-specific marker.[12]
See also
- Skin lesion
- List of cutaneous conditions
References
Further reading
- Schmidt, Christopher S; Bentz, Michael L (2005). "Congenital Smooth Muscle Hamartoma: The Importance of Differentiation From Melanocytic Nevi". Journal of Craniofacial Surgery. 16 (5). Ovid Technologies (Wolters Kluwer Health): 926–929. PMID 16192884.
- Copi, Luana Rocco Pereira; Peraro, Thaís de Freitas; Copi, Igor; Caldas, Adriana Cristina (2019). "Congenital smooth muscle hamartoma". Anais Brasileiros de Dermatologia. 94 (3). FapUNIFESP (SciELO): 376–377. PMID 31365679.