Clinical features of neonatal listeriosis in Taiwan: A hospital-based study

Neonatal listeriosis is a major cause of mortality in newborn; however, there is limited information about this disease in Taiwan. The aim of our study was to identify the outcome determinants, clinical features, and incidence of pregnancy-associated listeriosis, which includes both neonatal and maternal listeriosis.

We retrospectively analyzed the medical records of neonatal and maternal patients with pregnancy-associated listeriosis at two hospitals in Taiwan from January 2000 to December 2018. Listeriosis was indicated by positive Listeria monocytogenes culture.

Our study examined 18 neonates and 19 mothers. The neonatal and fetal death rate was 24%. All five cases of fetal losses or neonatal deaths occurred before 29 weeks of gestational age. The annual incidence of confirmed neonatal listeriosis increased significantly from 0.94/10,000 neonatal inpatients in 2000-2011 to 5.45/10,000 neonatal inpatients in 2012-2018 (p = 0.026). Clinical presentations of neonatal listeriosis included respiratory distress (85%), leukocytosis or leukopenia (77%), bandemia (69%), thrombocytopenia (77%), hypocalcemia (100%) and elevated C-reactive protein (CRP) levels (92%). Lower gestation correlated with a higher fatality rate (p = 0.002). Among the maternal cases investigated, 67% had a diagnosis of listeriosis, and 72% presented with fever. However, only 21% of the 19 mothers received complete antepartum ampicillin treatment.

The incidence of neonatal listeriosis is increasing, especially in preterm neonates. Maternal listeriosis should be adequately treated with appropriate empirical antibiotics.