Acute Onset Lactic Acidosis Secondary to Linezolid

Linezolid has been the mainstay of treatment for multidrug-resistant Gram-positive bacteria. Common adverse effects with linezolid include diarrhea, nausea, headache, and bone marrow suppression. A less common and understudied side effect is lactic acidosis. This study describes a 19-year-old man with linezolid-induced lactic acidosis (LILA). The patient was admitted for the management of acute decompensated systolic heart failure, which improved on guideline-directed medication therapy (GDMT). During hospitalization, he developed an erythematous weeping cellulitis infection of his right lower extremity and was started on linezolid 600 mg every 12 hours with wound and blood cultures collected. After one day of treatment with linezolid, lactic acid levels acutely increased from 1.8 mmol/L to 5 mmol/L without any other interventions. Suspecting possible LILA, linezolid was transitioned to cephalexin with a reduction of lactic acid to 2.4 mmol/L, one day following linezolid cessation. After two days of linezolid cessation, lactic acid levels decreased to 1.9 mmol/L. Lactic acidosis can have profound hemodynamic consequences for patients, including death. A meta-analysis study of 35 articles with 47 patients (28 males, 18 females, and one non-binary) was done, which found a 25.5% mortality rate associated with LILA. Due to this high mortality, having a greater understanding of the associated risk factors with LILA is very important. This case study aims to inform clinicians of the potential harmful side effects associated with linezolid, as well as the understudied risk factors involved in LILA that are needed to prevent its occurrence.

Linezolid-Induced Lactic Acidosis Presenting As Acute Cholecystitis: A Case Report and Systematic Review

Linezolid has gained increased use for the treatment of infections caused by multidrug-resistant Gram-positive bacteria in recent years. It can cause rare but potentially life-threatening lactic acidosis. Here, we presented a case report of linezolid-induced lactic acidosis (LILA), along with a systematic review of current literature. The patient was a 55-year-old male who presented with the symptoms of acute cholecystitis. He had been treated for sepsis due to acute cholecystitis with broad-spectrum antibiotics and intravenous fluids as per protocol. Still, his lactate level was getting elevated. After excluding other causes of lactic acidosis, LILA was diagnosed, and linezolid was discontinued. His lactic acid level, as well as his physical condition, improved after that. Studies related to LILA were searched in Medline via PubMed. After screening titles, abstracts, and full texts, data were extracted, tabulated, and presented in this article. The risk of bias was also assessed. We found 78 relevant articles in the primary search, and 26 articles, including 496 patients, were included in the study. From 23 studies of 129 patients, 28 patients (21.7%) died in the setting of LILA. The peak lactate level in which the patient developed LILA was 38.1 mmol/L after four weeks of therapy. The most common health conditions associated with LILA were end-stage renal failure (ESRD), diabetes mellitus (DM), hypertension, chronic obstructive pulmonary disease (COPD), etc. Eighteen studies with a total of 30 patients discontinued it after the development of LILA. Twenty-four patients (80%) out of 30 survived after the discontinuation. We recommend including LILA in the differential diagnoses when treating patients with lactic acidosis since LILA is associated with a relatively elevated mortality rate.