West nile virus case studies

Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1] Michael Maddaleni, B.S.

Case 1 overview

The first case presented displays a rare complication associated with West Nile Virus. Commonly, West Nile Virus is associated with neuro-invasive disorders, but there is also a tendency for it to cause myocarditis. It has become apparent that physicians need to be aware of the possible myocarditis complication because it can lead to a fatal arrhythmia. This particular case study involves a 65 year old man that initially presented with a virus that eventually suffered a fatal arrhythmia. Lab tests and autopsies showed that this particular patient developed encephalitis and myocarditis secondary to West Nile virus infection.

Case 1 Presentation

The patient was a 65 year old male of Scottish heritage. His clinical presentation showed:

• Cough
• Fever
• Decreased oral intake

His symptoms included:

• Nausea
• Weakness
• Blurred vision

His past medical history included:

• Diabetes
• Hypertension
• Former smoker

Upon arrival to the emergency department , the patients condition was relatively unremarkable. His electrocardiogram did in fact show a normal sinus rhythm at a rate of 83 beats/minute. The rest of this case is presented on a day by day basis.

Day 1

• Mild confusion and disorientation
• Blurred vision
• Fever of 103.4 degrees Fahrenheit
• The antibiotics being used at this point are:
  • Ceftriaxone
  • Vancomycin
  • Antiviral acyclovir

Day 2

• Head CT showed chronic inflammatory changes.
• Lumbar puncture showed colorless cerebrospinal fluid
• The following tests were negative
  • Bacterial and fungal
  • Herpes simplex virus PCR of the cerebrospinal fluid
  • Serum lyme antibodies
  • Blood cultures
• Vancomycin was stopped. Acyclovir and ceftriaxone are continued.
• A transthoracic echocardiogram showed an ejection fraction of 50-55%.
  • There was also abnormal left ventricular relaxation as well as the left atrium being dilated

Day 3

• On Day 3, the patient showed:
  • [Lethargy]]
  • Disorientation
  • Fever of 104.5 degrees Fahrenheit
• Antimicrobials were continued as before
• Electroencephalogram showed abnormal moderate generalized background slowing. This was consistent with diffuse encephalopathy.

Day 4

• No new complaints
• Lethargy continued
• Approximately ten minutes after morning rounds notice no new complaints, the patient was found without a pulse and unresponsive
• Electrocardiogram displayed asystole
• The patient was not on continuous cardiac monitoring so there was not another EKG to compare the new one to.
• CPR was unsuccessful

The autopsy performed revealed positive tests for West Nile Virus. The cardiovascular examination also displayed results consistent with myocarditis. It is also important to note that the results dis not show any signs of pulmonary embolism or acute myocardial infarction.