Herpes simplex virus 1 encephalitis in first trimester of pregnancy

Encephalitis caused by herpes simplex virus 1 (HSV-1) has been described in pregnancy, but it’s rare, with less than 20 cases being described in peer-reviewed literature. Physiologic changes in immune response during pregnancy influence the course of HSV-1 encephalitis (HSVE) and predispose pregnant women to severe complications. We present a case of herpetic encephalitis in a 12-weeks pregnant patient. In our patient neurologic condition deteriorated despite early diagnosis, appropriate antiviral and antiepileptic treatment, and suppurative neurocritical care, respectively. Disease progression stopped and the patient’s condition improved after pregnancy termination. Improvement could be a consequence of multiple factors, including delayed therapeutic effect of antiviral treatment, the impact of intensive care management, seizure control, and the possibility of spontaneous recovery as part of the natural disease course, respectively. This case highlights the potential severity of HSV-1 in early pregnancy and underscores the importance of multidisciplinary management and individualized decision-making in complex clinical situations.