Nguyen Matthew D, Dileep Gayathri, Quizon Marrey, Nguyen Vu, Demerci Arif, Hanna Ramy
Division of Nephrology, Hypertension and Transplant Nephrology, University of California, Irvine, CA, USA.
SAGE Open Med Case Rep. 2024 Nov 25;12:2050313X241302013. doi: 10.1177/2050313X241302013. eCollection 2024.
May-Hegglin anomaly (MHA) is a rare autosomal dominant disease associated with a mutation in the MYH-9 gene. It is characterized by macrothrombocytopenia and neutrophils with abnormal cytoplasmic inclusions. Clinical features of this disease include hearing loss, early cataracts, and renal failure. We present two interesting cases of renal injury attributed to MHA. The first is a 52-year-old Hispanic female with MHA-associated nephropathy and thrombocytopenia complicated by Stage 3 chronic kidney disease (CKD) and hypothyroidism. She was found to have a pathogenic MYH-9 heterozygous mutation with associated clinical characteristics. Due to her thrombocytopenia from MHA, patient is not a candidate for kidney biopsy. She has been treated with SGLT-2 inhibitors, Angiotensin Receptor Blockers (ARBs) for managing her Stage 3b CKD and Synthroid for hypothyroidism. Despite these treatments, she continues to have low platelet counts, proteinuria, and progressive CKD. Our second case highlights a 39-year-old white female with MHA associated with focal segmental glomerulosclerosis diagnosed at the age of 15 on renal biopsy. She also has thrombocytopenia and mixed connective tissue disease with rheumatoid arthritis and systemic lupus erythematosus clinical characteristics. She is currently on a regimen of methotrexate, Xeljanz, and IVIG for her rheumatological diseases. Her kidney function has remained stable on Angiotensin Converting Enzyme Inhibitors (ACEi) with hydrochlorothiazide and as needed loop diuretics for edema. These cases illustrate the challenges of diagnosing and managing renal complications associated with MHA due to the MYH-9 gene mutation. Chronic thrombocytopenia in both patients restricts the use of invasive diagnostic procedures, such as biopsies, which are critical for confirming the relationship between nephropathy and MHA, and for guiding further treatment. As such, these cases stress the importance of genetic testing as a key tool in diagnosis and emphasize the difficulties in managing patients with suspected MHA-associated nephropathy and thrombocytopenia.
May-Hegglin异常（MHA）是一种罕见的常染色体显性疾病，与MYH-9基因突变有关。其特征为大血小板减少以及中性粒细胞出现异常胞质内含物。该疾病的临床特征包括听力丧失、早期白内障和肾衰竭。我们呈现了两例归因于MHA的肾损伤有趣病例。第一例是一名52岁的西班牙裔女性，患有MHA相关肾病和血小板减少症，并发3期慢性肾脏病（CKD）和甲状腺功能减退。她被发现存在致病性MYH-9杂合突变及相关临床特征。由于她因MHA导致血小板减少，患者不适合进行肾活检。她接受了钠-葡萄糖协同转运蛋白2（SGLT-2）抑制剂、血管紧张素受体阻滞剂（ARB）治疗以控制其3b期CKD，以及左甲状腺素治疗甲状腺功能减退。尽管进行了这些治疗，她的血小板计数仍然偏低，存在蛋白尿，且CKD不断进展。我们的第二例病例是一名39岁的白人女性，15岁时经肾活检诊断为与局灶节段性肾小球硬化相关的MHA。她也有血小板减少症以及具有类风湿关节炎和系统性红斑狼疮临床特征的混合性结缔组织病。她目前正在接受甲氨蝶呤、托法替布和静脉注射免疫球蛋白治疗其风湿性疾病。她的肾功能在使用血管紧张素转换酶抑制剂（ACEi）联合氢氯噻嗪以及必要时使用袢利尿剂治疗水肿的情况下保持稳定。这些病例说明了由于MYH-9基因突变，诊断和管理与MHA相关的肾脏并发症所面临的挑战。两名患者的慢性血小板减少症限制了诸如活检等侵入性诊断程序的使用，而活检对于确认肾病与MHA之间的关系以及指导进一步治疗至关重要。因此，这些病例强调了基因检测作为诊断关键工具的重要性，并凸显了管理疑似MHA相关肾病和血小板减少症患者的困难。
