Background: The dengue virus belongs to the genus Flavivirus in the Flaviviridae family and is transmitted mainly by Aedes aegypti mosquitoes. It is a single-stranded positive-sense RNA virus existing as four serotypes (DEN-1-4). Hematological abnormalities are among characteristic laboratory findings in dengue. Thrombocytopenia and leukopenia are considered markers of dengue pathophysiology, reflecting bone marrow suppression. Objective: The aim of the study was the assessment of clinical profile, complete blood count and biochemical parameters, with particular emphasis on platelet indices, in patients hospitalized for dengue fever. The secondary aim was to evaluate laboratory risk factors for developing thrombocytopenia <100 G/l during hospitalization. Material and methods: We analyzed medical records of patients with confirmed dengue who were hospitalized between 2016 and 2024. Inclusion criteria contain: age ≥18 years old and positive dengue NS1 antigen test on admission. The presence of dengue IgM antibodies was not required. Exclusion criteria contain: any chronic diseases, confirmed viral, bacterial and parasitic co-infections. Group differences were assessed using the Student’s t-test, and correlations were evaluated using the Pearson coefficient. Results: We included clinical data of n=27 patients, female/male n=18/9 with the mean age of 37.6±10.1 years. All patients had dengue NS1 antigen and n=8/27 (29.6%) had detectable IgM anti-dengue antibodies. The mean duration of hospitalization was 6.04 days. The lowest mean platelet count (108.06 G/L) was observed on the third day of hospitalization. In the analyzed cohort, the most common CBC abnormalities were observed in WBC and NEU (100% of patients), PCT (92.6%), and PLT (63%). Baseline plateletcrit was the only platelet parameter significantly negatively correlated with thrombocytopenia <100 G/L. Baseline AST was the only parameter positively correlated with thrombocytopenia <100 G/L. Conclusions: Thrombocytopenia and leukopenia were observed in the majority of patients hospitalized for dengue. Baseline aspartate aminotransferase AST and plateletcrit were the only laboratory parameters associated with the development of more pronounced thrombocytopenia.