Table 1.

Causes of acrocyanosis

Type of acrocyanosis	Causes
Unilateral acrocyanosis
	Local trauma/digital injury
	Local infection: Paronechia
	Raynaud's phenomenon
	Thoracic outlet syndrome
	Carpel Tunnel syndrome
	Cervical tumors compressing neurovascular bundle* e.g. Neuroblastoma, stellate ganglion tumor
	Thromboembolism of arteries of palmar arch
	Frostbite
	Reflex Sympathetic dystrophy
Bilateral acrocyanosis**
	Benign acrocyanosis of infancy
	Frostbite
	Pernio
	Raynaud's phenomenon
	Reflex sympathetic dystrophy
	Hypoxemia**
	Congenital cyanotic heart disease**
	Methemoglobinemia**
	Purpura fulminans
	Pheochromocytoma

*: Need to look for other signs of Horner's syndrome on the ipsilateral side of the face (ptosis, anhydrosis, miosis of pupil or unequal pupils, poor light reflex and enopthalmos);**: Need close clinical evaluation for presence of central cyanosis.