[12] Community-Acquired Methicillin-Resistant Staphylococcus aureus (MRSA) Sepsis in a 29 Week Neonate

AK Hartman, JT Meadows, GJ Davis. University of Kentucky, Lexington, KY

Background: Community-acquired Methicillin-Resistant Staphylococcus aureus (MRSA) infections are becoming an increasing cause of significant morbidity and mortality among neonatal intensive care unit (NICU) patients. We present a case of disseminated MRSA sepsis resulting in the death of a 29 week premature infant.

Results: This 29 week infant, born to a 28 year old gravida 2 para 2 with necrotizing MRSA pneumonia and active skin lesions, was found to have disseminated MRSA sepsis at autopsy, following a sudden clinical decline. The mother was a poorly compliant insulin-dependent diabetic and a polysubstance abuser, including intravenous drugs. The infant's initial NICU course was relatively unremarkable. Her initial blood cultures were negative. On day of life (DOL) 4, she developed erythematous papulo-vesicular lesions on her right hand, arm, and leg, possibly reflecting herpes simplex virus (HSV) infection. Acyclovir was begun intravenously and administered for two days until HSV polymerase chain reaction (PCR) of the lesions returned negative. On DOL 9, the infant began having significant desaturations, tachycardia followed by bradycardia, and a metabolic acidosis resistant to bicarbonate. The infant died shortly after being taken off of life support. Blood, respiratory, and cerebrospinal fluid cultures taken before death were positive for MRSA. Gross and microscopic findings at autopsy confirmed disseminated sepsis with multiorgan abscess formation. The gross findings included multiple eroded papules over the chest, abdomen, limbs, and vulva. Examination of internal organs revealed abscess formation throughout the lungs and liver. Significant findings microscopically included abscess formation in the dermis, lungs, liver, spleen, heart, right kidney, and central nervous system. Thymic involution was present, as well as, a transverse growth arrest line of the costochondral junction, both signs of systemic stress. Cultures of the liver and spleen taken at autopsy were positive for MRSA.
Conclusions: In summary, this case represents a premature infant with MRSA sepsis who had an unremarkable initial newborn course and negative initial blood cultures. The mother was found to have multiple skin lesions and necrotizing MRSA pneumonia at the time of delivery. The rapid progression to death indicates the significant morbidity MRSA poses to premature infants.
Category: Autopsy

Wednesday, March 11, 2009 1:00 PM

Poster Session VI # 7, Wednesday Afternoon