Relationship between clinical and laboratory features with infecting dengue virus serotypes in a sample of dengue suspected adult patients from 2015-2017 in Sri Lanka

Dengue is a major viral disease affecting the tropics. Although previous research has focused on the relationship between the infecting dengue virus (DENV) serotypes and disease severity, less work has been done on the relationship between the clinical and laboratory features and the infecting DENV serotypes in Sri Lanka. We evaluated the relationship between the clinical and laboratory features and the infecting DENV serotypes in adult patients with clinically suspected dengue admitted to the Base Hospital, Mawanella, Sri Lanka from December 2015 to March 2017.

Blood samples of 200 dengue suspected patients were tested for the infecting DENV serotypes using a reverse transcription polymerase chain reaction with primers targeting the envelope region of the virus. Relationship between the infecting DENV serotypes with clinical and laboratory features was assessed using Z score and paired t tests.

Of the 200 patients tested, 39 (19.5%) were positive for DENV, any of the four DENV serotypes alone or in combination. The highest number of infections was noted with DENV-2 (n=18, 46.1%). Fever (P=0.000) and rash (P=0.017) were frequently noted in DENV negative patients while bleeding (P=0.012) was more frequently noted in DENV serotype positive patients. Platelet count of <100,000 μl⁻¹ was significantly associated with DENV serotype positivity (P=0.000). Platelet count of <100,000 μl⁻¹ (P=0.035) and haemoglobin (Hb) of >13mgdl⁻¹ (P=0.016) were noted in 15 of the 18 DENV-2 positive patients.

Clinical and laboratory features of severe dengue with bleeding manifestations, low platelet counts and high Hb were noted in DENV-2 infections.