Baylor University Medical Center Proceedings April 2014, Volume 27, Number 2 | Page 35
Table 2. Results of other laboratory tests
Blood test
Results
Antimitochondrial antibody
Absent
Antinuclear antibodies
Absent
Coccidioides/Rocky Mountain spotted fever antibody
Negative
C-reactive protein
<0. 3
Creatine kinase
24
Blood culture
Negative
Paraneoplastic panel
Negative
Enterovirus/herpes simplex virus
Negative
West Nile virus IgM
Positive
showed small bilateral pleural effusions and a small amount of
free fluid in the pelvis but no signs of primary malignancy. Laboratory test results were remarkable for the presence of WNV
immunoglobulin (Ig) M in the blood, with negative IgG and
negative polymerase chain reaction results (Table 2). Although
CSF WNV IgM titers were below the assay cutoff, they were
in fact found to be present at low levels. CSF WNV IgM was
tested after completion of intravenous immunoglobulin (IVIG)
treatment and while on high-dose steroids. Based on the clinical presentation and these laboratory findings, the diagnosis of
acute WNV meningoencephalitis was made. CSF and blood
cultures drawn prior to antibiotics were without any growths.
Prior to transfer to Baylor University Medical Center, the
patient was started on broad-spectrum antibiotics and antiviral coverage with doxycycline, meropenem, vancomycin, and
acyclovir but showed no signs of improvement. She was also
started on gabapentin and diazepam for nystagmus symptom
relief. Nausea and emesis were controlled with promethazine
and ondansetron. Upon transfer, the patient was immediately
started on IVIG with a total of 2 g/kg administered over 3 days.
On day 2 of IVIG, she was started on intravenous methylprednisolone 125 mg twice a day, which was later transitioned to
oral prednisone after 5 days. Within a couple of days of starting
IVIG and intravenous steroids, her symptoms of nystagmus and
ataxia showed visible improvement. On day 5, her symptoms
of headache, nausea, vomiting, and nystagmus had improved
significantly such that she was finally able to open her eyes and
eat. On day 6, oral prednisone, memantine, and oxcarbazepine
were started. Due to drowsiness, memantine and oxcarbazepine
were discontinued fairly quickly after initiation. By day 10, the
patient had full range of motion in all extremities, and OMS
had nearly resolved to the untrained eye.
The patient had become very deconditioned from being
bedbound for nearly 2 weeks with poor nourishment, requiring inpatient rehabilitation. Over the course of a year, she has
improved to the extent of being able to get groceries and take
care of her children. Using her eyes for prolonged tasks will still
cause her to be nauseated and worsen her headache. Although
her opsoclonic-nystagmoid movements are not visible outside of
ophthalmological evaluations, which do show small continued
April 2014
movement not obvious to the naked eye, she does have difficulty with reading. She also has intermittent problems with
urinary retention.
DISCUSSION
West Nile virus
According to the Centers for Disease Control and Prevention, in 2012, there were 5674 WNV cases in the United States
(4). Texas was particularly hit hard, with 1739 (32%) cases
reported (3). Severe cases of neuroinvasive WNV were initially
reported in 2002 and 2003 but have been increasing in frequency over the past several years. Just in 2012 alone, 2873 of
the reported WNV cases were neuroinvasive, with 286 repor FV@