Dengue hemorrhagic fever (DHF) and dengue shock syndrome (DSS)
A rare complication of dengue fever, DHF occurs most often in small children and elderly adults. If DHF occurs, it will usually do so by day 3-5 of infection. The relationship between DHF and previous dengue infection has not been clearly established, but previous exposure to dengue is correlated with subsequent DHF. Uncontrolled bleeding distinguishes DHF from fever accompanying a dengue infection. Bleeding can occur from the gums, nose, intestine, or under the skin as bruises or spots of blood, especially under a tourniquet.
In children, the progression of the disease is not always characteristic. A relatively mild first phase with an abrupt onset of fever, malaise, vomiting, headache anorexia, and cough is succeeded 2-5 days later by weakness and, sometimes, physical collapse. Frequently, spots appear on the forehead, arms, and legs, along with spontaneous bruises and bleeding from punctures where blood was taken. A seriously ill child may breathe rapidly and with considerable effort; the pulse may be weak, rapid, and thready.
The criteria for DHF are a platelet* count of less than 100,000 and a **hematocrit 20% greater than normal. Children with similar blood indicators should be hospitalised immediately and managed for potential DSS. The syndrome can be lethal and requires rapid in-hospital management with assiduous correction and replacement of fluid, electrolytes, plasma, and sometimes fresh blood/platelet transfusions. Mortality due to DHF and DSS ranges from 5-30% in the untreated Indonesian population, with the highest risk category being infants under one year of age.