BACKGROUND Digital necrosis is rarer than lower limb necrosis and constitutes a medical or surgical emergency. Etiological evaluation is required. Cold agglutinin disease is a cause of digital necrosis but diagnosis is difficult. METHODS Herein we report the case of a 57-year-old man presenting recent paroxysmal acrosyndrome of the left hand subsequently complicated by digital necrosis following occupational exposure to cold in his work as a forklift driver. After etiological evaluation, a diagnosis of primary cold agglutinin disease was made. Intravenous rituximab and topical treatment resulted in complete healing. CONCLUSIONS Cold agglutinin disease is a rare type of auto-immune hemolytic anemia. Following exposure to cold, paroxysmal cutaneous signs are frequent. The disease may be either primary or secondary with B-cell lymphoproliferative disorder, auto-immune disease or infection. A thorough workup is required. To date, the treatment combining the best positive response rate and good safety is rituximab in weekly perfusions over a 1-month period.