Abstract Background: Dengue fever continues to spread worldwide, particularly in tropical regions. Some patients with dengue fever may progress to severe dengue, which is associated with significantly higher morbidity and mortality. Despite this, no definitive treatment has been found to prevent its progression. Montelukast, a leukotriene receptor antagonist, has shown potential in reducing plasma leakage, a key factor in the pathophysiology of severe dengue. Therefore, this study aimed to evaluate the effectiveness of montelukast in reducing the risk of severe dengue. Methods: A systematic literature search was conducted on April 16, 2025, using keywords related to montelukast and dengue across four databases, which included PubMed, Taylor and Francis, Cochrane Library, and ScienceDirect. A critical appraisal was performed using the Oxford Centre for Evidence-Based Medicine framework, evaluating the validity, importance, and applicability of each study. The primary outcomes were the incidence of dengue shock syndrome and dengue with warning signs. The secondary outcomes included mortality rate and hospitalization duration. Results: This study included three studies involving a total of 1057 patients. Montelukast is associated with a reduced incidence of dengue shock syndrome and shorter duration of hospitalization. However, the effect of montelukast on dengue with warning signs and mortality rate was inconclusive. Conclusion: Montelukast shows potential as an adjuvant therapy in preventing the progression of dengue fever to severe dengue. However, further research is required before montelukast can be widely recommended for dengue fever patients in daily clinical practice and possibly integrated into dengue fever clinical guidelines.
evidence-based case report ; severe dengue ; dengue fever ; leukotriene receptor antagonist ; montelukast

Objective: To describe the clinical manifestation of patient with severe dengue, to identify the serotypes and genotypes of dengue viruses (DENV) which concurrently infecting the patient, and to explore the possible relationship of severe dengue with the concurrent infection of DENV. Methods: Dengue diagnosis was performed using NS1 antigen detection and IgG/IgM ELISA. Standard clinical and laboratory examinations were performed to obtain the clinical and hematological data. DENV concurrent infections were detected and confirmed using RT-PCR and DENV Envelope gene sequencing. Phylogenetic analyses were performed to determine the genotypes of the viruses. Results: The patient was classified as having severe dengue characterized by severe plasma leakage, hemorrhage, and organ damage involving lung, liver, and kidney. Concurrent infection of DENV serotype 2 and 3 was observed. The infecting DENV-2 virus was grouped into Cosmopolitan genotype while DENV-3 virus was classified into Genotype I. Both viruses were closely related to isolates that were endemic in Jakarta. Viremia measurement was conducted and revealed a significantly higher virus titer of DENV-3 compared to DENV-2. Conclusions: The occurrence of multi-serotype DENV infections was presented in a patient with severe clinical manifestation in Indonesia. The hyperendemicity of dengue in Indonesia may contribute to the DENV concurrent infections cases and may underlie the severity of the disease.