Researchers Document Rare Cases Of West Nile Virus

An outbreak of the virus last summer in New York City in which five people died marked the first time the virus had been detected in North America.

In one case, a 69-year-old man with a history of hypertension was brought to the emergency department of Long Island Jewish Medical Center in New Hyde Park, NY, with progressive weakness. The illness steadily progressed and the patient was admitted to the Intensive Care Unit with the initial diagnosis of Guillain-Barré Syndrome. Within 24 hours the patient was unable to walk, three days later he was unable to breathe without ventilation, and by day 10 he was severely paralyzed.

A condition affecting multiple nerves in the body and ranging from mild tingling in one extremity to total paralysis of the body, Guillain-Barré Syndrome had never before been associated with West Nile infection. The rapidly progressing illness did not respond to treatment and the West Nile virus went undiagnosed until several weeks following the patient's admission.

"This case emphasizes the need for great vigilance for this virus," said neurologist Richard Libman, MD, of the Long Island Jewish Medical Center Department of Neurology, an author of the case study. "This includes checking all patients with symptoms of weakness, keeping in mind the wide variety of possible presentations, including the very unusual ones."

In light of this case, Libman recommends that all patients diagnosed with Guillain-Barré Syndrome be tested for West Nile virus.

In another case, a healthy 15-year-old boy was hospitalized following three days of fever, headache, vomiting and confusion. The boy did not show symptoms consistent with other cases from the 1999 New York outbreak, but spinal fluid and blood taken from the boy were positive for the West Nile virus.

The child's symptoms included confusion and cranial nerve problems such as a depressed gag reflex and an inability to coordinate voluntary muscular movements. West Nile viral infections commonly cause an inflammation of the brain called encephalitis that usually includes symptoms of coma and seizures. However, the boy exhibited neither of those symptoms. The boy eventually lost the ability to swallow on his own and had to be fed through a tube. Fortunately, the boy's symptoms gradually subsided, and within six months his condition had returned to normal.

"This case demonstrates that life-threatening complications may occur in the early phase of the disorder but are not permanent," said neurologist Charles A. Nichter, MD, of Columbia University.

Nichter stressed the importance for health care providers to be aware of potentially life-threatening brain stem-related problems that can arise from West Nile virus and the need to help patients to swallow and breathe in severe cases.

The typical West Nile viral infection includes a mild inflammation of the brain, fever, head and body ache, skin rash and swollen lymph glands. Headache, high fever, neck stiffness, disorientation, coma, convulsions, muscle weakness, paralysis and death can occur. West Nile virus is a mosquito-borne illness, first isolated in Uganda in 1937 and later detected in greater Africa, Asia and Europe.

There is no specific treatment for West Nile virus. In more severe cases hospitalization, intravenous (IV) fluids, airway management, respiratory support (ventilator), prevention of secondary infections (pneumonia, urinary tract, etc.), and good nursing care are recommended.

A neurologist is a medical doctor with specialized training in diagnosing, treating and managing disorders of the brain and nervous system.

The American Academy of Neurology, an association of more than 16,500 neurologists and neuroscience professionals, is dedicated to improving patient care through education and research.

For more information about the American Academy Neurology, visit its Web site at http://www.aan.com. For online neurological health and wellness information, visit NeuroVista at http://www.aan.com/neurovista.