The differences of clinical manifestations and laboratory findings in children and adults with dengue virus infection

Abstract

Background

Dengue haemorrhagic fever is an important public health problem and mainly occurs in children less than 15 years of age. Recently, the incidence of the disease have increased in adults but data on clinical and laboratory presentations of those affected are limited.

Objectives

To assess and compare clinical manifestations and laboratory findings of dengue virus infected children and adults in Thailand.

Study design

A 1-year study was conducted from September 2003 to August 2004 for dengue virus infected patients admitted to Phetchabun Provincial Hospital, Thailand. Physical signs, symptoms, and laboratory features were recorded. All dengue patients were confirmed using immunochromatographic test on convalescent sera.

Results

Based on serology-confirmed dengue virus infection, there was 286 dengue patients including 15 (5.3%) dengue fever and 271 (94.7%) dengue haemorrhagic fever (DHF). Among DHF cases, clinical classifications were DHF I, 40.9%; DHF II, 43%; and DHF III or dengue shock syndrome (DSS), 10.8%. Of all dengue patients, 231 cases (80.8%) were children aged less than 15 years and 55 cases (19.2%) were adults. The highest proportion of child cases was DHF I (42.9%), whereas that of adults was DHF II (51%). Some clinical manifestations were more common in adult patients, such as petechiae, melena, headache, retro-orbital pain, joint pain, myalgia, nausea and vomiting (p-value < 0.05). Signs found commonly in children were epistaxis, oliguria, and liver enlargement (p-value < 0.05). Haemoconcentration, thrombocytopenia, increased alanine aminotransferase, and longer prothrombin time were found to be significantly higher in adults than in children (p-value < 0.05).

Conclusions

Some clinical presentations of dengue disease and laboratory findings in adults are different from those in children. Therefore, adults as well as pediatric cases of DHF need appropriate and prompt case management to reduce the mortality rate of DHF.

Introduction

Dengue fever (DF), dengue haemorrhagic fever (DHF), and dengue shock syndrome (DSS) are now considered the most important arthropod-borne viral diseases worldwide. The global prevalence of dengue cases has increased in South-East Asia, Africa, the Western Pacific and the Americas (Calisher, 2005, Guzman and Kouri, 2002). An annually estimated 500,000 DHF patients require hospitalization. DHF is a leading cause of death in children. Case-fatality rates are usually 2.5%, can exceed 20% but can be reduced to <1% with rapid diagnosis and proper treatment of the patients. DHF is a major public health problem in Thailand and continues as an endemic disease with outbreaks every rainy season and large epidemics every 2–3 years or every in consecutive years (Department of Communicable Disease, 2004). DHF occurs primarily in children less than 15 years of age with the highest attack rate in the 5–9 years age group (Nimmannitya, 1987), recently, however, the peak age of DHF patients has shifted to 10–14 years of age (Kittigul et al., 2003; Department of Communicable Disease, 2004). The shift in age predominance of DHF patients might be related to changes in places of dengue virus transmission, from households to the school environment, or to changes in the age structure of the population (Patumanond et al., 2003). A gradually marked increase of dengue virus infection in adults has been noted in several countries (Hammond et al., 2005, Kularatne et al., 2005, Wichmann et al., 2004). In Thailand, affected adults aged over 15 years old are reported to comprise 30–40% of dengue virus infected cases according to the Epidemiological Surveillance System. Previous studies have described the severity of clinical bleeding found in adult dengue patients (Lee et al., 2006, Malavige et al., 2006, Wichmann et al., 2004). Age-related differences in dengue severity are poorly understood and the data on clinical features in dengue adults are limited. This study was carried out to determine the differences in the clinical manifestations and laboratory findings of hospitalized children and adults with dengue virus infection.