Hemorrhagic fever with renal syndrome complicated with central nervous system symptoms: clinical analysis of 98 cases. Often presents with twitching aura. Severe central nervous system symptoms occur during the oliguric stage on the basis of renal damage, accompanied by high blood volume, cerebral edema, and pulmonary edema. Mannitol cannot be used because it would not only fail to work but also exacerbate cerebral edema, pulmonary edema, and heart failure. Treatment should include efficient diuretics, catharsis, bloodletting, and dialysis among other measures. Central nervous complications of HFRS can occur in all periods of severe and critical types. Symptoms are associated with uremia, high blood volume, severe infection, and electrolyte imbalances. The main manifestations include severe viremia, hypertensive encephalopathy, brain edema, and cerebral hemorrhage. Meningeal irritation syndrome, pathological syndromes, and brain edema appear related to cerebral vasodilation, bleeding, and micro-thrombosis in the brain parenchyma caused by the cerebral pia mater. In this group of 98 cases, 29 cases died, with a mortality rate reaching 24.5%, significantly higher than those without central nervous complications (the total mortality of HFRS patients in our hospital over the past 10 years was 3%).