Significant Pathology in Young Infants Presenting with Hypothermia: A Multicenter Study
CLINICAL QUESTION: Among infants aged 90 days or younger who present to the emergency department (ED) or hospital with hypothermia, what is the prevalence of significant pathology, and what pathology is seen?
BACKGROUND: Hypothermia is a common reason for presentation in young infants. In contrast to neonatal fever, there is limited guidance on the management and expected outcomes of neonatal hypothermia. To guide evaluation and treatment, further study of the prevalence of significant pathology in hypothermic infants is needed.
STUDY DESIGN: Multicenter, retrospective, cohort study
SETTING: ED or hospital at nine academic children’s hospitals across the U.S.
SYNOPSIS: A total of 14,278 charts were reviewed. Ultimately, 998 previously healthy infants aged 90 days or younger who presented with a temperature of 36.0°C or lower were included.
Infants were grouped into three outcome categories: 1) Serious bacterial infection (SBI) or herpes simplex virus (HSV), 2) “Other significant pathology,” defined as a discharge diagnosis that required hospitalization, and 3) no significant pathology. While SBI and HSV were relatively uncommon in hypothermic infants (4%), a wide variety of other significant pathologies (28%) presented with hypothermia. The most common other significant pathologies were respiratory disease (39%) and endocrine, metabolic, and nutritional diseases (28%). Rare pathologies such as botulism and neurological infarction were also described.
Infants who were more than 28 days old at presentation, were ill-appearing, had multiple episodes of hypothermia within 24 hours, or had an abnormal white blood cell count had increased odds of having SBI/HSV or other significant pathology.
Limitations include missing laboratory results for some infants, possibly introducing bias, and a lack of generalizability to populations other than previously healthy infants presenting to academic children’s hospitals.
BOTTOM LINE: In infants aged 90 days or younger presenting with hypothermia of 36.0°C or lower, about one-third had significant pathology. While 4% of the cohort had SBI or HSV, 28% had other pathologies across a variety of organ systems.
CITATION: Wood JK, et al. Significant pathology in young infants presenting with hypothermia: a multicenter study. Hosp Pediatr. 2025;15(10):804-813. doi: 10.1542/ hpeds.2025-008387.
Dr. Fennell
Dr. Jackson
Dr. Fennell and Dr. Jackson are pediatric hospitalists at Nationwide Children’s Hospital and assistant professors of pediatrics at The Ohio State University College of Medicine, both in Columbus, Ohio.