Differential Diagnosis of Leptomeningeal Enhancement in the Pediatric Population
Gabriela Bou1, Adam Goldman-Yassen2, Morgan Morris4, Monideep Dutt3, Phaethon Philbrook5, Grace Gombolay6
1Department of Neurology, Emory University School of Medicine, 2Department of Radiology, Emory University School of Medicine/Children's Healthcare of Atlanta, 3Emory University School of Medicine/Children's Healthcare of Atlanta, 4Emory University, 5Department of Genetics, Louisiana State University Health Sciences Center, 6Department of Neurology, Emory University/Children's Healthcare of Atlanta
Objective:

To determine the differential diagnosis of leptomeningeal enhancement (LME) and compare the rates of LME by diagnosis in children


Background:
LME is a radiologic manifestation seen in various central nervous system diseases, including malignancies, infections, and neuroimmunological disorders. The presence of LME has been estimated at different frequencies in various neuroimmunological disorders. However, the relationship between LME in the pediatric population and the prevalence of the associated diseases remains unknown.
Design/Methods:
A retrospective chart review of pediatric patients with new leptomeningeal enhancement (LME) on brain MRI at Children’s Healthcare of Atlanta between January 1-December 31, 2022 was performed. Data was collected on age at detection of LME, patient demographics, diagnosis, and ancillary tests including serum and cerebrospinal fluid (CSF) studies. Statistical analysis was performed using R CRAN.
Results:
Sixty patients were included with a mean age of 7.5 (standard deviation (SD): 6.0) years at the time of LME. Etiologies for LME, from highest to lowest, were as follows: infectious (N=28, 47%), oncologic (N=16, 27%), neuroinflammation (N=5, 8%, including N=3, 5% with anti-MOG antibody associated disorder (-MOGAD)), and other (N=14, =24%). The types of infections included: group A streptococcus, streptococcus anginosus, and listeria. The types of oncologic disorders included: rhabdomyosarcoma, diffuse midline glioma, acute lymphocytic or promyelocytic leukemia, melanoma, pilocytic astrocytoma, diffuse leptomeningeal glioneuronal tumor, myxopapillary ependymoma, choroid plexus carcinoma, and high grade glioma. Other etiologies included: hemiplegic migraine, seizures, hypoxic ischemic encephalopathy, moyamoya, Sturge Weber, and unknown. Median CSF WBC count was highest in infectious (308, interquartile range-IQR 110-962), as compared to inflammatory (66.5, IQR 163.5-258) and oncologic cases (5.5, IQR 1.0-16.0).
Conclusions:
The differential diagnosis for LME is broad, but most commonly includes infection, followed by oncologic conditions, and then inflammatory conditions. MOGAD is the most common neuroinflammatory cause of LME and should be considered in children.
10.1212/WNL.0000000000205342