Predicting Severe Short-Term Neurologic Outcomes in Human Parechovirus Meningoencephalitis

BACKGROUND AND OBJECTIVES: Human parechovirus (PeV) is an increasingly recognized cause of meningoencephalitis (ME) in infants. The US 2022 outbreak provided opportunity to analyze the clinical presentation and predictors of severe disease in affected infants. METHODS: We conducted a multicenter retrospective review of infants diagnosed with PeV ME during the outbreak. We examined demographics, clinical features, laboratory findings, and neuroimaging results. Logistic regression was used to identify predictors of complicated disease and abnormal brain magnetic resonance imaging (MRI). Complicated disease was defined as requiring intensive care or findings of an abnormal brain MRI or electroencephalogram. RESULTS: 139 infants had PeV ME. The median age was 19 days. Fever was the most common presenting symptom (89.2%) and was associated with uncomplicated disease and normal MRI. A total of 42 (30.2%) infants had complicated disease. Hypothermia (36.5% vs 5.1%), somnolence (38.1% vs 13.4%), poor feeding (76.1% vs 47.4%), hemodynamic instability (28.5% vs 3%), seizures (57.1% vs 4.1%), apnea (40.4% vs 0%), hypoglycemia (16.6% vs 1%), mechanical ventilation (23.8% vs 0%), and inotropic support (11.9% vs 0%) were associated with complicated disease. Younger age and seizures were predictors of abnormal MRI on multivariable analysis (adjusted odds ratio, 0.92 [0.48-0.99] and 40.1 [3.49-460.7], respectively). Laboratory findings, including cerebrospinal fluid indices, were rarely abnormal. CONCLUSION: Despite nonspecific symptoms on presentation and normal laboratory values, PeV can cause complicated disease, requiring clinicians to maintain high suspicion for this infection. We suggest PeV evaluation in workup of infant sepsis cases, neuroimaging in patients at high risk, and long-term developmental follow-up.