A 13-Month-Old Iranian Boy with Thrombosis of the Left Transverse and Superior Sagittal Sinuses Due to Homozygous Mutations in MTHFR A1298C: A Case Report & Review of Literature

Background and Aims: Cerebral sinus venous thrombosis (CSVT) is a rare stroke subtype in children, with limited data on its clinical presentation, etiology, and outcomes. This case report aims to describe a case of CSVT in a child, including their clinical presentation, imaging findings, and management, to increase awareness of this rare but serious condition. Case presentation: A 13-month-old boy presented with swelling and deviation of the left eye after being hospitalized for left periorbital cellulitis. The patient was diagnosed with thrombosis of the left transverse and superior sagittal sinuses and underwent treatment with levetiracetam, folinic acid, rosuvastatin and enoxaparin followed by warfarin. Genetic testing was also performed to identify the underlying genetic basis of thrombophilia. Results: Laboratory tests showed that there was one heterozygous mutation in the β-Fibrinogen gene and three homozygous mutations in MTHFR A1298C, PAI-I-675 4G/5G, and PAI-I-844 G/A genes. Additionally, Lipoprotein (a) was measured at 89.3 nmol/L and the patient's mother had two homozygous mutations in PAI-I-675 4G/5G and PAI-I-844 G/A genes. Conclusions: It appears that the mutation in MTHFR gene is more prevalent in our region, which may be a contributing factor to the increased incidence of stroke in children and adolescents in the country. Further research is needed to determine the prevalence of this mutation and its impact on thrombophilia in the population. This case highlights the importance of prompt diagnosis and treatment of CSVT in children, as well as the need for genetic counselling and testing to identify underlying risk factors.