Rare occurrence of sagittal sinus thrombosis and haemorrhagic infarction with dengue fever: jumping from traditional symptoms to lethal neurological consequences.

Introduction and importance: Dengue virus (DENV) is an RNA virus transmitted by Aides mosquito causing dengue fever. There is growing recognition of neurological symptoms associated with DENV infection, some of which might be lethal if left untreated. Case reports describing sagittal sinus thrombosis, as a serious neurologic consequence of dengue infection, are rare. It is still unknown how often sagittal sinus thrombosis occurs and what variables increase the risk in dengue patients. Case presentation: Herein the authors presented an elderly Sudanese patient diagnosed with dengue fever. He was admitted, then 2 days after admission, the condition was complicated by atrial fibrillation, sagittal sinus thrombosis complicated by massive left temporal lobe infarction with haemorrhagic transformation and recurrent episodes of status epilepticus. After receiving the necessary care, his condition remained the same and no progress or deterioration was seen. Clinical discussion: Sagittal sinus thrombosis can happen due to several underlying causes. DENV can very rarely lead to such condition. The authors' patient developed this condition, which was later complicated by ischaemic stroke with haemorrhagic transformation and status epilepticus. In addition to a familial history of DVT and a history of myocardial infarction, our patient also acquired cardiac mural thrombus and DVT throughout his illness, which increased the suspicion of a protein C, protein S, or antithrombin 3 deficiency. Conclusion: Sagittal sinus thrombosis with haemorrhagic infarction associated with thrombocytopenia is a very rare kind of stroke that occurs in dengue. Dengue as a pathogenic mechanism of ischaemic stroke requires validation with further data.