ABSTRACT
INTRODUCTION: Polymerase chain reaction (PCR) testing of cerebrospinal fluid (CSF) is a sensitive and specific method in diagnosing herpes simplex virus (HSV) encephalitis. However there are increasing reports of false negative HSV PCR. CASE DESCRIPTION: We present a patient in the 9th decade of life with abnormal behavior and focal seizures with MRI showing a right temporal T2 hyperintense non-enhancing lesion with electrographic evidence of right lateralized periodic discharges. CSF analysis and PCR for HSV-1 and 2 yielded negative results twice, and therefore acyclovir was discontinued. Patient initially improved following correction of hyponatremia. Patient however deteriorated and imaging revealed a new right parietal lesion. Third CSF sample showed lymphocytic pleocytosis with positive HSV-1 PCR. Patient improved following antiviral treatment. DISCUSSION: Acyclovir treatment should continue in high clinical suspicion scenarios despite negative HSV PCR. We further discuss causes of PCR false negatives and challenges it poses for patient care.
ABSTRACT
INTRODUCTION: Clinical presentation of the central nervous system Lyme disease is nonspecific and therefore brain imaging and disease-specific serological testing is generally pursued to assist with diagnosis. Brain imaging findings are, however, rare and often unspecific. CASE DESCRIPTION: In the current report, we are presenting a rare magnetic resonance imaging (MRI) finding of extensive meningeal enhancement in two patients with acute Lyme disease. DISCUSSION: We discussed clinical implications and reviewed the relevant literature.
