Dengue fever is the most important arboviral infection in the world, with an estimated 100 million cases per year and 2.5 billion people at risk. Encephalopathy is a rare complication of dengue virus infection and may occur as a consequence of intracranial hemorrhage, cerebral edema, hyponatremia, cerebral anoxia, fulminant hepatic failure with portosystemic encephalopathy, microcapillary hemorrhage or release of toxic products. We report a rare case of hemorrhagic encephalopathy in dengue shock syndrome caused by type 3 dengue virus.

INTRODUCTION: Type 3 dengue virus caused an extensive epidemic in the state of Rio de Janeiro in summer 2002. In some of the patients, it was found in an atypical form with increased aminotransferase levels and acute hepatitis. MATERIAL AND METHODS: An analysis was made of 1,585 serologically confirmed dengue cases at the Dengue Reference Center in Campos dos Goytacazes, Rio de Janeiro state. The grade of hepatic aggression was established according to the alterations in the aminotransferase levels: grade A - normal levels of aminotransferase; grade B - elevated aminotransferase, with increased levels of at least one of the enzymes; grade C - elevated aminotransferase, with the levels of at least one of the enzymes increased to more than three times the reference values; grade D - acute hepatitis, with aminotransferase levels increased to at least 10 times their normal values. RESULTS: Among the 1,585 serologically confirmed dengue cases, 44.5% presented alterations in the aminotransferase levels (grade B), 16.9% presented grade C liver involvement and 3.8% of the patients had progressed to acute hepatitis (grade D). The average values for the rise in aspartate aminotransferase and alanine aminotransferase were 93.3 U/L and 86.0 U/L. The greatest alterations were observed among females (p<0.001), cases of dengue hemorrhagic fever (p<0.001), and cases with sequential infections (p=0.001). CONCLUSIONS: Liver damage with elevation of aminotransferases and reactive hepatitis was a common complication of dengue virus infection in these patients.

Dengue fever is the most frequent arbovirus disease in the world and the most important one in terms of morbidity and mortality. Atypical manifestations of dengue have become commonplace during the last few years, including hepatic damage, which manifests mainly by pain in the right hypochondrium and an increase in the levels of aminotransferases. We describe a case of acute hepatitis in a patient with Dengue Shock Syndrome Grade III. We analyzed the clinical and laboratory aspects of this atypical complication of dengue as well as the differential diagnoses.