Rare case of cold agglutinin disease presenting with Livedo Reticularis

Dr Konika Sharma and Dr Anush Patel at Bassett Medical Center, Cooperstown, NY have reported a rare case of cold agglutinin disease presenting with Livedo Reticularis. The case has appeared in the New England Journal of Medicine.

Cold agglutinin disease is a rare disorder characterized by autoimmune hemolytic anaemia occurring at low temperatures. Physical examination findings, often limited to acrocyanosis, are combined with a thermal amplitude test to help establish the diagnosis. Livedo reticularis is thought to be due to spasms of the blood vessels or an abnormality of the circulation near the skin surface. It makes the skin, usually on the legs, look mottled and purplish, in sort of a netlike pattern with distinct borders.

A 70-year-old woman presented to an outpatient clinic with a 1-week history of dizziness and a generalized rash after the onset of a viral respiratory tract infection 2 weeks earlier. On physical examination, she had a generalized, macular, non-blanching rash in a reticular pattern with purplish discolouration consistent with livedo reticularis (Panel A). Because of the spontaneous agglutination of the blood (Panel B), the blood samples were warmed in a saline bath at 37°C (Panel C, showing agglutinated blood on the left and warmed blood on the right).

Laboratory evaluation revealed a hematocrit of 14% (reference range, 34 to 46), an indirect bilirubin level of 7.6 mg per deciliter (reference value, <1.0), and a lactate dehydrogenase level of 1298 U per liter (reference range, 100 to 190). The direct antiglobulin test was positive for the complement component C3, and the test for cold agglutinins was positive at a 1:2048 dilution at 4°C.

A diagnosis of cold agglutinin disease, a form of acquired autoimmune hemolytic anemia, was made, a condition that may have been exacerbated by the patient’s recent viral infection along with the cold weather in upstate New York, where the temperature was 15°F (−9°C) at the time of her presentation. The patient was warmed and treated with blood transfusions and rituximab for 1 week. At the time of hospital discharge, she had a hematocrit of 30% and a reduction in dizziness, but the rash persisted.