Skin Lesions at Subcutaneous Heparin Injection Sites in a Patient with Heparin-Induced Thrombocytopenia (HIT)

 

Clinical features:

(1) history of subcutaneous injection of heparin

(2) presence of anti-heparin antibodies

(3) development of lesions at the injection sites that may be painful and/or pruritic:

(3a) indurated, erythematous nodules or plaques

(3b) necrosis of overlying skin with formation of an eschar

 

Associated findings may include:

(1) thrombocytopenia, especially if there is continued use of heparin

(2) arterial and/or venous thrombosis

 

Skin biopsy may show:

(1) thrombosis of small dermal blood vessels

(2) edema

(3) dermal lymphocytic infiltrate

(4) subcutaneous fat necrosis

 

Differential diagnosis:

(1) infection at the injection site

(2) panniculitis