Salmonella Infantis Meningitis in a Pediatric Patient After in-Utero Exposure to Ustekinumab

Abstract

Abstract Introduction/Objective Salmonella meningitis is associated with a significant neurological sequelae, subdural effusions, cerebral infarction, encephalitis, cerebral abscess, and high mortality. It is a rare complication of Salmonella sepsis and occurs almost exclusively during early infancy. Salmonella is identified as pathogen in less than 1% of confirmed cases of bacterial meningitis in infants. Immunocompromised individuals have higher risk of having invasive salmonellosis. Methods/Case Report We present a case of 4-month-old male with no significant past medical history who was presented to emergency department with five days history of fever, cough and decreased oral intake. At the time of admission, complete blood count was obtained and showed a platelet count of 702 x 10(3)/mcL, hematocrit of 25% and WBC of 17.0 x 10(3)/mcL with differential showing absolute neutrophilia and absolute monocytosis. Head ultrasound was concerning for meningoencephalitis with bilateral parenchymal echogenicity and bilateral subdural collections. Lumbar puncture showed WBC cell count of 229 (36 % PMNs, 52% lymphocytes, 12% monocytes), red blood cells of 0, glucose of 13 mg/dL, protein of 151 mg/dL. Meningitis multiplex PCR panel of the CSF was negative. MRI of the brain showed findings suggestive of meningitis with associated subdural empyema and ventriculitis without hydrocephalus. CSF culture identified Salmonella species that is susceptible to ampicillin and ceftriaxone which later identified as Salmonella infantis by the State laboratory. Immunodeficiency workup including next generation sequencing immunodeficiency panel did not reveal any known causes. Of note, mother has psoriasis and was treated with ustekinumab; an antibody against a cytokine subunit shared by IL12 and IL23, during pregnancy. The patient responded to antibiotic treatment and was discharged in a stable condition. Results (if a Case Study enter NA) N/A. Conclusion This case report highlights Salmonella infantis meningitis in a pediatric patient who was exposed to ustekinumab in utero which could cause drug induced immunodeficiency state as IL-12 is known to activate macrophages and macrophages are critical for Salmonella clearance. Although ustekinumab level was undetected in the patient right prior to discharge, the long half-life and mechanism of action of this medication could have caused an immunodeficiency state which allowed rare Salmonella infantis meningitis.