NO_x (Nitrite/Nitrate) in Cerebral Spinal Fluids Obtained from Patients with Influenza-Associated Encephalopathy

Abstract

It has become evident that the number of patients with a new type of influenza-associated encephalopathy is increasing in Japan. Nitric oxide (NO), a simple free radical gas, elicits a wide range of physiological and pathophysiological effects. We measured the nitrite/nitrate (NO_x) levels in cerebral spinal fluid obtained from patients with influenza-associated encephalopathy in order to evaluate the correlation between the NO production and the process of influenza-associated encephalopathy. Fifteen children were enrolled, aged from 1 to 9 years. As control we used 14 cerebral spinal fluids obtained from patients with urinary tract infection, respiratory infection or mumps meningitis without any sequela. NO₃ in influenza-associated encephalopathy was significantly higher than that of control group. On the other hand NO₂ was not significantly higher than that of control group. In particular, 4 out of 5 fatal cases revealed high NO₂ or NO_3. One case having normal levels in NO₂ and NO₃ showed that NH₃ was high. These results revealed that NO plays a role in influenza-associated encephalopathy through indirect effects of NO.

Key words

Influenza virus - encephalopathy - nitric oxide - central nervous system - cerebral spinal fluids

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