Bellofatto Ilaria Anna, Sessarego Marta, Tirandi Amedeo, Olivero Chiara, Sgura Cosimo, Maioli Elia, Gavoci Aurora, Schiavetta Elisa, Frè Federica, Saccomanno Benedetta, Zaottini Federico, Picasso Riccardo, Fiorillo Chiara, Liberale Luca, Ottonello Luciano Carlo, Bardi Nicholas, Montecucco Fabrizio
IRCCS Ospedale Policlinico San Martino Genoa-Italian Cardiovascular Network, Larogo Benzi 10, Genoa 16132, Italy.
Radiology Unit, Department of Health Sciences (DISSAL), University of Genoa, Via Pastore 1, Genoa 16132, Italy.
Case Rep Med. 2023 Dec 16;2023:6550473. doi: 10.1155/2023/6550473. eCollection 2023.
3-Hydroxy-3-methylglutaryl coenzyme A reductase (HMGCR) inhibitors are widely used worldwide to treat dyslipidaemia and prevent cardiovascular events. Statins can cause a wide variety of muscle injuries ranging from myalgia to severe rhabdomyolysis. In most cases, these symptoms are mild and self-limiting and do not require specific treatment besides drug withdrawal. Statin-induced autoimmune necrotizing myopathy (SINAM) is a rare but potentially fatal complication, characterized by the subacute onset of progressive proximal muscle weakness and considerably high creatine phosphokinase (CK) levels in patients exposed to statins. The diagnosis is supported by the presence of antibodies HMGCR, which allows the differentiation from other forms of necrotizing autoimmune myopathies. Symptoms usually progress even after statin discontinuation and can determine severe muscle damage. . We describe the case of a 77-year-old man who developed SINAM after 5 years of statin use. He suffered from muscle functional impairment mainly involving proximal lower limb muscles which progressed to the point that he almost became bedridden. Initial treatment with prednisone alone was not effective, and he required a combination therapy with steroids, methotrexate, and intravenous immunoglobulins. After 5 months of therapy and rehabilitation, he showed complete laboratory response and muscle strength recovery.
Recognizing SINAM is paramount in order to promptly start treatment and avoid permanent muscle damage. Using a combination therapy from the beginning could contribute to a better outcome. Prompt statin cessation, categorization of the muscle disease by autoantibody testing, imaging, and histology, exclusion of malignancy, and anti-inflammatory therapy with corticosteroids, antimetabolites, immunoglobulins, and in some cases rituximab are currently accepted approaches to this entity.
3-羟基-3-甲基戊二酰辅酶A还原酶（HMGCR）抑制剂在全球范围内被广泛用于治疗血脂异常和预防心血管事件。他汀类药物可导致从肌痛到严重横纹肌溶解等多种肌肉损伤。在大多数情况下，这些症状较轻且具有自限性，除停药外无需特殊治疗。他汀类药物诱导的自身免疫性坏死性肌病（SINAM）是一种罕见但可能致命的并发症，其特征为在使用他汀类药物的患者中，渐进性近端肌无力亚急性发作，肌酸磷酸激酶（CK）水平显著升高。抗HMGCR抗体的存在支持该诊断，这有助于将其与其他形式的坏死性自身免疫性肌病相鉴别。即使停用他汀类药物后，症状通常仍会进展，并可能导致严重的肌肉损伤。我们描述了一例77岁男性在使用他汀类药物5年后发生SINAM的病例。他主要出现下肢近端肌肉功能受损，病情进展到几乎卧床不起的程度。最初单独使用泼尼松治疗无效，他需要类固醇、甲氨蝶呤和静脉注射免疫球蛋白联合治疗。经过5个月的治疗和康复，他的实验室检查结果完全恢复正常，肌肉力量也得以恢复。
认识SINAM对于及时开始治疗并避免永久性肌肉损伤至关重要。从一开始就采用联合治疗可能会带来更好的结果。目前公认的针对该疾病的治疗方法包括：立即停用他汀类药物，通过自身抗体检测、影像学和组织学对肌肉疾病进行分类，排除恶性肿瘤，以及使用皮质类固醇、抗代谢药物、免疫球蛋白进行抗炎治疗，在某些情况下还可使用利妥昔单抗。
