ABSTRACT
INTRODUCTION: Radiologically negative subarachnoid hemorrhage (SAH) has a low incidence and is associated with good clinical outcomes. CASE REPORT: We present the case of a 44-year-old male with new-onset headaches, which began one week prior while bike riding. At an outside hospital, he had normal computed tomography head and angiogram. He declined a lumbar puncture. Over the following week, the headache was persistent. He lacked meningeal signs. Repeat studies were normal. Lumbar puncture was positive for xanthochromia. CONCLUSION: Radiologically negative SAH should be included in the differential diagnosis of patients presenting with unremitting headache in the setting of recent exercise, despite negative imaging, and meningeal signs.
ABSTRACT
Background: Primary central nervous system lymphoma (PCNSL) is a rare, aggressive form of non-Hodgkin lymphoma contained in the brain and the spinal cord as well as the meninges, cranial nerves, eyes, and cerebrospinal fluid (CSF). Due to its variable presentation and lack of associated B-symptoms, it is quite challenging to diagnose PCNSL, if there is not a high level of suspicion. Methods: This is a retrospective case series examining 13 human immunodeficiency virus- (HIV-) negative patients with PCNSL and DLBCL type, with a median age of 75 years old. Results: The most common presenting symptom was altered mental status. The frontal lobes, basal ganglia, cerebellum, and corpus callosum were most affected. Prior to brain biopsy, 4/13 patients were on steroids, which did not affect biopsy results and the average time to diagnosis was 1 month. 9/13 patients who did not receive steroids had an average time to diagnosis of less than 1 month. Conclusion: Although steroid administration did not appear to diminish the yield of the biopsy, it is a best practice to withhold steroids prior to biopsy to decrease the time to diagnose PCNSL.
ABSTRACT
Neurologic manifestations of sarcoidosis are rare, and even rarer still are cases of isolated neurosarcoidosis. The clinical presentation of isolated neurosarcoidosis can be highly variable, and diagnosis is particularly challenging, the gold standard being tissue biopsy. We describe a patient with a history of atypical parkinsonian syndrome and chronic right frontal lobe infarct who developed weakness, imbalance, and gait disequilibrium in 2008, with magnetic resonance imaging at that time showing leptomeningeal and nodular enhancements in the bilateral frontal and parietal lobes. The patient had an extensive negative workup in 2010 but ultimately did not receive a definitive diagnosis with a tissue biopsy until 2020. The patient also notably failed a 3-month course of steroids after his biopsy due to a lack of symptomatic improvement. This case highlights the clinical variability and diagnostic difficulties of isolated neurosarcoidosis. We also highlight that our patient did not have any symptomatic improvement on steroids, which do typically provide some relief for patients.
ABSTRACT
Background: Powassan is a positive-sense, single-stranded, enveloped RNA virus that is a tick-borne Flavivirus, transmitted by Ixodes species, with groundhogs being the usual mammalian host. The virus is endemic to North America, with peak transmission during the summer and fall. The incubation period is 7-34 days, followed by a prodrome of flu-like symptoms. Although most infected individuals are asymptomatic, the virus can penetrate the CNS to produce a viral encephalitis. The key to the diagnosis is a positive serology. Results: The patient is a 62-year-old male with a past history of a right putamen infarct, hepatitis C, hypertension, and substance abuse who presented due to acute onset altered mental status, dysarthria, and left-sided facial droop. He had several tick bites around the time of presentation in December. He was empirically treated for possible meningitis, as CSF revealed WBC 370 (80% mononuclear cells); RBC 10, protein 152 mg/dL, and glucose 59 mg/dL. An MRI scan of the brain showed a subacute left putamen stroke. MRAs of the head and neck were unremarkable. A Mayo Clinic Encephalopathy Panel was unremarkable; however, a New York State Arbovirus panel revealed Powassan IgM ELISA as well as Powassan Polyvalent microsphere immunofluorescence assay reactivity. His hospital course was complicated by critical illness myopathy and respiratory failure requiring tracheostomy. Conclusion: The Powassan virus is a known etiology for encephalitis in North America. Although the peak incidence of transmission is in the summer and fall, this does not exclude transmission during other seasons. Due to the increasing prevalence of Powassan virus in Lyme-endemic areas particularly in the Midwest and Northeast, United States, patients with an unexplained altered mental status in these regions should be screened for Powassan virus, regardless of the time of year.
