Thursday April 16, 2009

Scenario: 42 year old female presented with weakness, ataxia, nausea, slurred speech, dehydration, and severe lethargy. Lab showed high anion gap metabolic acidosis. Patient was made NPO and was resuscitated with IVF and empiric antibiotics. Patient stabalized within 24 hours. Review of old record showed similar multiple episodes with no clear diagnosis before each discharge except for one unrelated admission 12 years ago for uneventful gastric bypass surgery.

Patient "bounced back" to ICU after 2 days with similar clinical presentation. Due to clerical error D-Lactic acid was marked instead of L-Lactic acid on lab slip and indeed it is reported high and patient was diagnosed with "D-Lactic acidosis". What is D-Lactic Acidosis?


Answer: There are 2 kinds of Lactic Acidosis

L-lactate: It is the only form produced in human metabolism, and its excess represents increased anaerobic metabolism due to tissue hypoperfusion.

D-lactate: It is a byproduct of bacterial metabolism and may accumulate in patients with short-gut syndrome or in those with a history of gastric bypass or small-bowel resection.

Development of "D-Lactic acidosis" occurs due to carbohydrate malabsorption with ingestion of large amounts of carbohydrate, and colonic bacterial flora of a type that produces d-lactic acid. It get worse due to diminished colonic motility, allowing time for nutrients in the colon to undergo bacterial fermentation.


Reference: click to get abstract

D-lactic acidosis. A review of clinical presentation, biochemical features, and pathophysiologic mechanisms - Medicine (Baltimore) 1998 Mar;77(2):73-82