Shifting trends in clinical parameters among dengue-infected patients in Bangladesh during the 2024 outbreak: A study based on demographic characteristics and IgG status

Dengue fever, a common mosquito-borne viral illness in tropical and subtropical areas, is endemic in over one hundred countries. Recent dengue outbreaks in Bangladesh exhibited higher morbidity and a notable change in signs and symptoms, making the disease pattern more complicated. Yet the inadequate knowledge regarding the shifting of clinical parameters leads to inaccurate diagnoses and constrained treatment options. This study sought to assess the changing patterns of clinicopathological markers across various stages of the disease. Data were collected from 211 (137 dengue-positive and 74 dengue-negative) hospitalized patients in Chattogram, Bangladesh during the 2024 dengue outbreak. The dengue-positive patients were categorized into groups according to age, gender, and IgG status (primary or secondary infection). We evaluated the parameters throughout five stages of the disease utilizing Prism GraphPad-10. In our study, older (>40 years) patients exhibited lower platelet counts over an extended period. Besides, a decrease in hematocrit and hemoglobin levels, along with an increased ESR (Erythrocyte Sedimentation Rate), NLR (Neutrophil-Lymphocyte Ratio), ALT (Alanine Transaminase), and AST (Aspartate Transaminase) was noted among older (>50 years) patients. In males and females, differences in the changing patterns of platelet count, hematocrit, ALT, and AST were observed. Significant differences in many indices between IgG-negative and IgG-positive patients have been noted. Compared to IgG-negative patients, IgG-positive patients exhibited lower platelet counts and higher ESR, NLR, AST, and ALT. Interestingly, hematocrit changing patterns were similar in IgG-positive and IgG-negative patients, while the pattern for NLR was substantially different. Initial NLR was high (>4) in IgG-positive patients, reducing significantly (p***=0.0001) at the following stage and lowering to 2 until the last stage, while IgG-negative patients maintained NLR around three. This research will help to elucidate the disease patterns of current dengue infections by providing significant insights into the changing clinical parameters during the period of the disease. Author SummaryThe recent dengue outbreak in Bangladesh demonstrated high morbidity and irregular signs and symptoms. However, there is a lack of sufficient studies illustrating the alterations in clinical parameters associated with disease progression, which are necessary for a comprehensive understanding of the disease patterns. This study evaluates the changing patterns of clinical parameters throughout the disease course in 137 dengue patients in Bangladesh. We observed a greater severity of the disease among elderly patients and a variation in the changing pattern of several clinical parameters between males and females. Significant deviations of platelet count, neutrophil to lymphocyte ratio, and liver enzyme level in blood were noted among dengue infected patients. Most importantly, IgG positive patients had a different pattern of disease compared to IgG negative patients. Individuals with IgG positivity exhibited a low platelet count, an elevated neutrophil to lymphocyte ratio and liver enzyme levels, and significant fluctuations in these parameters throughout the disease course, in contrast to IgG negative patients. These findings will enhance the understanding of the infection pattern of current dengue outbreak and guide treatment strategies considering the clinical parameters.