Texas Tech University Health Sciences Center, El Paso, USA.
The University of Texas at El Paso, USA.
J Investig Med High Impact Case Rep. 2022 Jan-Dec;10:23247096221117919. doi: 10.1177/23247096221117919.
Methemoglobinemia is a rare cause of hypoxia and can be a diagnostic challenge early in the disease course. The incidence of medication-induced methemoglobinemia is more common than congenital-related methemoglobinemia. The most common cause of methemoglobinemia is exposure to household detergents, illicit drugs, or medications with nitrate or sulfonamide chemical groups. The 2 main medications accounting for up to 45% of medication-induced cases are dapsone and benzocaine. We report a case of hypoxia and diarrhea with an arterial blood gas (ABG) showing methemoglobinemia at 26%. Infectious and autoimmune workup were negative. Methemoglobinemia level returned to normal level within 2 weeks of hydrochlorothiazide discontinuation, suggesting medication-induced methemoglobinemia at appropriate hypertension dosage. In this case, there was an acute rise in methemoglobin levels following initiation of an hydrochlorothiazide-losartan combination, which improved following the discontinuation of hydrochlorothiazide. Extensive workup ruled out cytochrome b5 reductase (Cb5R) and Glucose-6-phosphate dehydrogenase (G6PD) deficiency, which raised the suspicion of hydrochlorothiazide-induced methemoglobinemia, as it is part of the sulfa drug family.
高铁血红蛋白血症是一种罕见的缺氧原因，并且在疾病早期可能具有诊断挑战性。药物引起的高铁血红蛋白血症的发病率比先天性高铁血红蛋白血症更为常见。高铁血红蛋白血症最常见的原因是接触家用清洁剂、非法药物或含有硝酸盐或磺胺化学基团的药物。导致高铁血红蛋白血症的 2 种最常见药物是氨苯砜和苯佐卡因，占药物引起的病例的 45%。我们报告了 1 例高铁血红蛋白血症导致的缺氧和腹泻病例，动脉血气（ABG）显示高铁血红蛋白血症为 26%。感染和自身免疫检查均为阴性。氢氯噻嗪停药后 2 周内高铁血红蛋白水平恢复正常，提示在适当的高血压剂量下发生药物引起的高铁血红蛋白血症。在这种情况下，氢氯噻嗪-氯沙坦联合使用后高铁血红蛋白水平急性升高，停用氢氯噻嗪后改善。广泛的检查排除了细胞色素 b5 还原酶（Cb5R）和葡萄糖-6-磷酸脱氢酶（G6PD）缺乏，这增加了对氢氯噻嗪引起的高铁血红蛋白血症的怀疑，因为它是磺胺类药物家族的一部分。
