Methemoglobinemia is a rare disorder associated with oxidization of divalent ferro-iron of hemoglobin (Hb) to ferri-iron of methemoglobin (MetHb). Methemoglobinemia can result from either inherited or acquired processes. Acquired forms are the most common, mainly due to the exposure to substances that cause oxidation of the Hb both directly or indirectly. Inherited forms are due either to autosomal recessive variants in the CYB5R3 gene or to autosomal dominant variants in the globin genes, collectively known as HbM disease.

Our recommendations are based on a systematic literature search. A series of questions regarding the key signs and symptoms, the methods for diagnosis, the clinical management in neonatal/childhood/adulthood period, and the therapeutic approach of methemoglobinemia were formulated and the relative recommendations were produced. An agreement was obtained using a Delphi-like approach and the experts panel reached a final consensus >75% of agreement for all the questions.

高铁血红蛋白血症是一种与血红蛋白二价铁 (Hb) 氧化为高铁血红蛋白铁 (MetHb) 相关的罕见疾病。高铁血红蛋白血症可由遗传或获得性过程导致。获得性形式最常见，主要是由于暴露于直接或间接引起 Hb 氧化的物质。遗传形式是由于 CYB5R3 基因的常染色体隐性变异或珠蛋白基因的常染色体显性变异，统称为 HbM 病。

我们的建议是基于系统的文献检索。制定了一系列关于关键体征和症状、诊断方法、新生儿/儿童期/成年期的临床管理和高铁血红蛋白血症的治疗方法的问题，并提出了相关建议。使用 Delphi 样方法获得了一致性，专家小组对所有问题达成了 > 75%一致性的最终共识。