A Public Health Alerts report today details two US infants with severe neurologic symptoms after infection with Paenibacillus dendritiformis, raising awareness of an emerging infectious disease threat.

Public Health Alerts, a new collaboration between NEJM Evidence and CIDRAP, fills a gap in reliable data, offering expert-reviewed reports that translate frontline observations into actionable public health evidence. An NEJM Evidenceeditorial  explains the initiative further.

Empiric antibiotics may be inadequate

The first case involved a 2-month-old girl born extremely prematurely, at 26 weeks’ gestation a year ago in Pennsylvania. Her blood and cerebrospinal fluid (CSF) cultures grew Paenibacillus thiaminolyticus, a gram-positive spore-forming bacterium widely found in the environment.

Brain imaging showed progressive hydrocephalus, encephalomalacia, and abscesses, which required placement of a shunt.

The infant was treated with a variety of antibiotics but at age 8 months was still not able to eat by mouth, sit unsupported, or roll over.

The second case involved a 37-day-old boy born at 33 weeks’ gestation who had been doing well following a 22-day stay in the neonatal intensive care unit and 15 days at home. He returned to the hospital because of poor feeding and unresponsiveness. Blood and CSF cultures also grew P thiaminolyticus.

Although P thiaminolyticus was identified by matrix-assisted laser desorption ionization time of flight mass spectrometry (MALDI-TOF MS) in both cases, whole-genome sequencing of isolates from both infants identified P dendritiformis. This bacterium is soil-dwelling and is also gram-positive and spore-forming.

The author concluded, “Clinicians who care for young infants should be aware of this emerging pathogen, as empiric antibiotic regimens for treating bacteremia and meningitis may be inadequate, and pediatric neurosurgical expertise for abscess drainage or treatment of hydrocephalus is typically needed.”