C53-16 When the Treatment Turns Toxic: Linezolid-induced Lactic Acidosis

Abstract Introduction Linezolid is an antibiotic that is effective against multi-drug resistant infections, however, it has several adverse effects that must be considered when administering the drug. Key toxicities include neurological side effects including mitochondrial toxicity, and severe metabolic acidosis from type B lactic acidosis. Case Description A 68-year-old female was admitted to the ICU following a prolonged hospital course including spinal decompression/fusion in the setting of chronic back pain complicated by epidural abscess s/p multiple I likely driven by infectious/metabolic causes, medication toxicity (specifically Linezolid), hospital acquired delirium and possible non-convulsive seizures, which was ruled out by EEG. LP was avoided given the large, infected wound in the L spine that would have been at high risk of introducing infection into CNS, if meningitis was not already present. The patient continued to develop worsening mental status and lactic acidosis. She was started on a bicarbonate drip and was intubated for airway protection. She had progressive lactate elevation despite no evidence of bowel ischemia on CTA abd/pelvis, no evidence of worsening infection, and no necrotizing fasciitis on evaluation of her sacral wound. Linezolid toxicity was thought to be the driving factor in her worsening mental status as well as significant lactic acidosis in the setting of no other obvious source. CRRT was started to help treat the acidosis, but the patient continued to develop worsening shock requiring numerous pressors, and unfortunately passed away. Discussion Linezolid toxicity is an important diagnosis to consider when presented with an encephalopathic patient on long term linezolid therapy, specifically who is presenting with lactic acid elevation without any other known source. Given that this is a diagnosis of exclusion, but a fatal diagnosis if not considered, it must remain on the differential diagnosis when a patient is presenting with worsening lactate elevation and shock picture, and linezolid should be promptly discontinued. While the mortality rate of toxicity remains high, quick initiation of CRRT, both to address the severe acidosis and to help increase clearance of the drug, may be beneficial to improve outcomes, though further studies need to be established. This abstract is funded by: None