Siddiqui Nazia, St Peter Deidre M, Marur Surendra
Department of Medicine, Greater Baltimore Medical Center, Baltimore, MD, USA.
J Community Hosp Intern Med Perspect. 2017 Dec 14;7(6):358-362. doi: 10.1080/20009666.2017.1407209. eCollection 2017.
It is well documented that central nervous system (CNS) infections may lead to syndrome of inappropriate anti-diuretic hormone secretion (SIADH), but diagnosing these can prove difficult in patients with atypical presentations. We present a case of SIADH and muscle weakness in a patient without typical signs of CNS infection who was tested and diagnosed with neuroborreliosis based largely on her likelihood of exposure. This case indicates the need for Lyme testing in patients with unexplained SIADH who live in endemic areas. The patient was an 83-year-old female with a history of type 2 diabetes and hypertension, who presented from her primary care physician's office when her sodium was found to be 123 mEq/L. Her sole symptom was proximal muscle weakness. The diagnosis of SIADH was reached based on laboratory data. A trial of fluid restriction was initiated, but neither her sodium nor her muscle weakness improved. Lyme testing was performed as the patient lived in an endemic area and was positive. Lumbar puncture showed evidence of neurologic involvement. After realizing the appropriate treatment for hyponatremia in this case, intravenous ceftriaxone was started, and patient's sodium levels improved and muscle weakness resolved. Studies show that SIADH is associated with CNS infections, likely related to the inflammatory cascade. However, the atypical presentation of neuroborreliosis for our patient delayed the appropriate diagnosis and treatment. Our case demonstrates the need to screen for Lyme disease in endemic areas in patients presenting with neurologic symptoms and SIADH.
中枢神经系统（CNS）感染可能导致抗利尿激素分泌异常综合征（SIADH），这已得到充分证实，但对于非典型表现的患者，诊断可能会很困难。我们报告一例SIADH合并肌肉无力的病例，该患者没有CNS感染的典型体征，主要基于其暴露可能性接受检测并被诊断为神经莱姆病。该病例表明，对于生活在流行地区且患有不明原因SIADH的患者，需要进行莱姆病检测。患者为一名83岁女性，有2型糖尿病和高血压病史，因发现血钠为123 mEq/L而从其初级保健医生办公室转诊。她唯一的症状是近端肌肉无力。根据实验室数据诊断为SIADH。开始进行限液试验，但她的血钠和肌肉无力均未改善。由于患者生活在流行地区，进行了莱姆病检测，结果呈阳性。腰椎穿刺显示有神经受累的证据。在明确了该病例低钠血症的适当治疗方法后，开始静脉注射头孢曲松，患者的血钠水平得到改善，肌肉无力症状消失。研究表明，SIADH与CNS感染有关，可能与炎症级联反应有关。然而，我们患者神经莱姆病的非典型表现延迟了适当的诊断和治疗。我们的病例表明，对于出现神经症状和SIADH的流行地区患者，有必要筛查莱姆病。
