Solitary hemorrhagic cutaneous mastocytoma of infancy with digital localization: a case report

Solitary cutaneous mastocytoma is the most common form of pediatric cutaneous mastocytosis and usually follows a benign, self-limited course. However, atypical clinical presentations such as hemorrhagic or bullous evolution and uncommon anatomical localization may raise diagnostic concerns and lead to unnecessary investigations. We report the case of a male infant presenting with a solitary hemorrhagic mastocytoma localized on a finger. The lesion showed episodic blistering and hemorrhage after minimal mechanical stimulation, without systemic symptoms. Dermoscopic examination revealed a structureless erythematous-violaceous background without melanocytic features. Histopathological analysis demonstrated a dense dermal mast cell infiltrate with strong CD117 and CD25 expression, confirming the diagnosis. Conservative management resulted in spontaneous regression without sequelae. This case highlights the importance of clinicopathological correlation in recognizing atypical presentations of solitary mastocytoma and avoiding misdiagnosis and overtreatment.