Cold-induced cutaneous smooth muscle hamartoma

Area of Science:

• Dermatology
• Pathology
• Medical Case Reports

Background:

• Cutaneous smooth muscle hamartomas (SMHs) are typically congenital benign smooth muscle tumors.
• Classic SMH presentations include hyperpigmentation, hypertrichosis, and pseudo-Darier's sign.

Purpose of the Study:

• To report a rare case of early-onset acquired SMH with a unique cold-induced presentation.
• To highlight the diagnostic importance of external stimuli in SMH.

Main Methods:

• A case study of a 49-year-old woman with an acquired SMH.
• Clinical observation of lesion behavior upon cold exposure and rewarming.
• Histopathological examination of the lesional tissue.

Main Results:

• The patient presented with an acquired SMH that appeared during adolescence.
• Cold exposure triggered a transient, linear, wrinkled, hyperpigmented papular lesion.
• The lesion resolved spontaneously upon rewarming, and histology confirmed SMH.

Conclusions:

• This case represents a unique, transient presentation of SMH elicited by cold.
• The findings expand the clinical spectrum of SMH and emphasize the role of environmental stimuli in diagnosis.