Case Presentation: A 50 year old African American male presented to the Emergency Room with headache, nausea, vomiting, and three seizures in the past 24 hours. The patient was recently discharged from a hospitalization for similar symptoms which were attributed to increased intracranial pressure. After an extensive workup, including MRIs of the brain and spine with contrast which showed abnormal leptominingeal enhancement, as well as cerebrospinal fluid (CSF) studies that showed elevated protein and an absence of infectious or malignant markers, the patient was given a presumed diagnosis of isolated Neurosarcoidosis. The patient’s symptoms improved during that admission with a spinal tap and administration of systemic steroids. The patient was discharged with oral steroids and acetazolamide. Between admissions the patient presented to the ED with abdominal pain and was found to have nephrolithiasis. He was treated with intravenous fluids, analgesia, tamsulosin, and discharged home. Due to the pain and nausea from the kidney stone, the patient missed several doses of prednisone and acetazolamide. On readmission to the hospital, the patient was initially noted to have no focal neurological findings on exam and a CT scan of the head was stable compared with prior imaging. Due to the symptoms of increased intracranial pressure (ICP), seizure, and missed doses of prednisone, the patient was restarted on intravenous steroids. During the hospital course, despite resuming systemic steroids, the patient developed sinus bradycardia with heart rates ranging from 20 beats per minute (bpm) to 60 bpm. He experienced frequent pauses as long as 4.74 seconds on telemetry monitoring. While bradycardic he had no mental status changes and his systolic blood pressures (SBPs) were in the 140s-160s (baseline SBPs 100-120). The patient continued to have headaches and developed bilateral facial and abducens nerve palsies. A lumbar puncture (LP) was performed revealing an opening pressure of 41cm of water. Immediately following the LP, the patient’s heart rate rose to 90-100 bpm and his SBP dropped to the 100-110 range. Additionally, the patient’s headaches and cranial nerve deficits resolved.
Discussion: Cushing’s reflex is a physiologic response of the nervous system to increased intracranial pressure. First described by neurosurgeon Harvey Cushing in 1901, the reflex consists of elevated blood pressure (increased sympathetic tone to ensure cerebral perfusion is maintained in the setting of elevated intracranial pressure, which compresses the cerebral arteries), bradycardia (increased parasympathetic activity as a result of increased blood pressure), and abnormal breathing or apnea (abnormalities in the brainstem).
Conclusions: Elevated ICP is known to cause bradycardia and hypertension. In this patient with presumed Neurosarcoidosis and elevated ICP, a therapeutic bedside lumbar puncture led to an immediate resolution of profound sinus bradycardia and a decrease in blood pressure, as well as a gradual amelioration of other signs and symptoms of the disease.