Overview of aseptic meningitis after MMR vaccination in a group of Iranian infants in Children’s Medical Center

Background: CNS infection can be focal or generalized. Meningitis, besides other etiologies, can occur after a viral infection or viral vaccine. Although meningitis can occur in at any age but it is more common in children less than five years old. Aseptic meningitis and meningoencephalitis are two of the most common complications of mumps (wild type or vaccine). As a result of their serious complication, we decided to obtain more information about clinical manifestations and laboratory findings after the injection of the Hoshino MMR vaccine in a group of children in an Iranian referral hospital. Methods: In this cross-sectional study, performed from March 2013 to February 2015 on 73 children with meningochemical symptoms of meningitis, children who have been diagnosed with aseptic meningitis followed by an MMR vaccine in an infectious ward or emergency department of the Children’s Medical Center were enrolled in the study and their information was recorded from their files. A questionnaire was provided for children with diagnostic criteria of aseptic meningitis and their data were collected. Results: The gender ratio of patients was 46 males to 27 females. After collecting the symptoms of meningitis, the frequency of symptoms in these patients was as below: fever 66%, headache 49.3%, nausea and vomiting 74%, parotid swelling 0%, seizure 21.9% and meningeal symptoms 37%. Their laboratory data showed that 8.2% of patients had normal WBC and 76.7% had Abnormal results in their CSF (Cerebrospinal fluid) analysis. Mumps PCR (Polymerase chain reaction) was positive in 85% of samples. Conclusion: our study revealed that nausea and vomiting were the most frequent symptom after MMR vaccination in children and fever was in second grade in aseptic meningitis. There was no relation between clinical symptoms together, therefore we should take care of children after MMR vaccination to avoid complications when they become symptomatic.