Salicylates, nitric oxide, malaria, and Reye's syndrome

Area of Science:

• Medical Science
• Pathology
• Pharmacology

Background:

• Reye's syndrome incidence decreased globally after discouraging salicylate use in febrile children.
• Salicylate toxicity shares clinical features with severe falciparum malaria, common in African regions where salicylates are widely used.
• A proposed hypersensitivity mechanism for Reye's syndrome lacked established biological pathways.

Purpose of the Study:

• To investigate the potential mechanism linking salicylate use, infectious diseases, and Reye's syndrome.
• To explore the role of inducible nitric oxide synthase (iNOS) in salicylate-mediated exacerbation of infections.

Main Methods:

• Review of clinical observations of salicylate toxicity and malaria.
• Experimental evidence on salicylate's effect on the interferon gamma-iNOS pathway.
• Analysis of iNOS expression in fatal malaria, acute fevers, and Reye's syndrome cases.

Main Results:

• Salicylate enhances the interferon gamma signaling pathway, prolonging iNOS activity.
• Strong iNOS expression was observed in fatal malaria and acute fevers in African children.
• Widespread iNOS expression was found in fatal Reye's syndrome tissues.

Conclusions:

• Salicylate use in febrile children may exacerbate serious infections like falciparum malaria through iNOS enhancement.
• Reduced Reye's syndrome incidence may be linked to decreased salicylate use.
• iNOS pathway modulation by salicylates is a potential mechanism for Reye's syndrome pathogenesis.