Ophthalmic complications of dengue: pathogenesis and prevention.

To The Editor: The report of Tabbara1 on dengue retinochroiditis is timely and makes practitioners and physicians to consider various ophthalmic manifestations and complications of dengue fever. Unfortunately these are discussed seldom during clinical rounds and teaching sessions. It is surprising that ophthalmic complications were not cited much in recent papers.2,3 As genetic susceptibility4 is known for dengue infections, genetic predisposition might explain the susceptibility of a subset of dengue affected individuals for ophthalmic complications which needs further study. Recently ophthalmic manifestations following West Nile virus infection, another flavivirus, have been reported,5 so the author could have considered West Nile infection also.

Additional investigations such as functional status of platelets, platelet receptor polymorphism, defects in megakaryotes and platelet antibodies might have carried out in order to rule out platelet dysfunction as a contributory factor for hemaorrhagic episodes observed in the case reported. Dengue virus appears to infect the endothelial cells of blood vessels. As angiotension converting enzyme inhibitors (ACEIs) have a protective effect on blood vessels, the chemoprophylactic effects of ACEIs to prevent vasculogenic (vascular) complications of dengue fever are worth exploring. Also, it might be interesting to observe whether patients on ACEIs escape vasculogenic complications, if they are infected by dengue fever virus.

Investigators need to identify the various target proteins, amino acid residues and mimickers of amino acid residues, and their binding activity to dengue viral infection triggers or alters the immune mechanism resulting in post-dengue ophthalmic complications.6 Overall, there is a need to identify the susceptible population for complications of dengue fever and to introduce prophylactic agents to prevent or minimize complications of dengue fever.