A Case of Hemoglobin Variant (Hb J-Lome) Complicated by Abnormally Low HbA1c at the Onset of Fulminant Type 1 Diabetes Mellitus

Abstract

Fulminant type 1 diabetes mellitus (FT1DM), a new type 1 diabetes subtype, is characterized clinically by acute almost complete pancreatic β cell destruction. In contrast to markedly elevated plasma glucose, HbA1c is normal or only slightly elevated at FT1DM onset. We report the case of a 47-year-old man with FT1DM complicated by abnormally low hemoglobin. At diabetic ketoacidosis onset, glycated albumin (GA) was 25.3 %, HbA1c abnormally low at 3.6 %, and the GA/HbA1c ratio markedly high at 7.0. We identified a Lys → Asn mutation in 59 of the β-chain globin gene, yielding a diagnosis of Hb J-Lome. A complication of abnormal hemoglobin is thus to be suspected in cases of FT1DM with abnormally low HbA1c or a markedly high GA/HbA1c ratio.