Dengue is an Aedes aegypti mosquito-borne infection, caused by dengue virus serotypes 1,2,3 and 4. It is a major public health problem in tropical countries [4]. There are few reports of DF and DHF in pregnancy from literature review. Nowadays, the incidence has been increasing among adults [1, 3], more cases of DF and DHF in pregnancy like this present case can be found.
The clinical pictures of this case were the same as found in non-pregnant patients and previous reports [2, 5, 6]. She had acute dengue viral hepatitis with bleeding tendencies. However, she had no other associated features that might fulfill the criteria as described by the World Health Organization [7], such as rise in the hematocrit (≥ 20%) and clinical evidence of increased vascular permeability, manifested by generalized edema, pleural effusion and ascites. These presentations might be confused with other obstetrics complications, such as HELLP syndrome (hemolysis, elevated liver enzyme and low platelet counts) and other medical disease. A high index of suspicion is therefore required for the diagnosis, especially in areas of endemicity. Detailed history taking is helpful in diagnosis. The others hematologic signs, such as thrombocytopenia and atypical lymphocytosis, similarly detected in this case are also helpful for the diagnosis [8]. Serologic test is used to confirm the diagnosis and detect the specific serotype. Serologic diagnosis depends on the presence of IgM antibody or a rise in IgG antibody titer in paired acute and convalescent phase serum. Currently, the most widely used IgM assay is a capture ELISA (enzyme-linked immunosorbent assay). If sample positive for IgM capture ELISA, it should be reported as a probable dengue, not a confirmed dengue, since IgM antibody may persist at detectable levels for two or more months after infection. For a diagnosis of confirmed dengue, dengue virus should be identified by isolation, immuohistochemistry in necrosy tissue, or there should be a four-fold rise in antibody titer using a type-specific plaque reduction neutralization test [9]. This case was confirmed secondary dengue infection by four-fold rise in IgG antibody using the haemagglutination inhibition test.
Regarding the effect of DF and DHF in pregnancy, it hardly caused any infant abnormality, but DHF might be responsible for fetal death [4]. Fortunately, in this case, the baby appeared normal. Although rare, there had been reports about vertical transmission of dengue virus [2, 5]. Those cases occurred at or near the time of delivery. Those infants had common clinical features of thrombocytopenia, fever, hepatomegaly and varying degrees of circulatory insufficiency [5]. However, this case occurred remote from term pregnancy, and these clinical features were not found in newborn infant.
Another possible effect of DF and DHF in pregnancy is bleeding due to severe thrombocytopenia especially in high risk cases, such as placenta previa [4]. In this case, although the patient had very low platelet counts, no hemorrhagic complication was occurred. Platelet concentration was not given. This suggests that platelet concentration may not be given even severe thrombocytopenia regardless of clinical bleeding.
Management of this case was conservative, with intravenous fluid replacement and close observation of vital signs and bleeding, as practiced in the non-pregnant cases and previous reports [2, 5, 6]. Blood component should be prepared but given only in bleeding cases.