Background DKA is a severe acute complication of diabetes mellitus.

Thiamine (vitamine B1) is a water-soluble vitamin that plays a key role in aerobic glucose metabolism. It is a cofactor of pyruvate dehydrogenase (PDH), an enzyme that must be stimulated for entry into Krebs cycle for aerobic metabolism. In thiamine deficit states (as in diabetes - thiamin loss in urine), PHD activity is reduced resulting in a shift in pyruvate metabolism to the anaerobic pathway, increasing lactate production and acidosis.

Case Report(s) We prescribe the case of a 16-month-old baby girl, with insulin-dependent diabetes, who was admitted to the emergency department with tachycardia, altered state of consciousness and severe ketoacidosis.

She has an initial HbA1C at 11% at diagnosis, and the autoimmune workup showed positive level of anti-GAD confirming the autoimmune mechanism of her diabetes mellitus. Her stay in the Intensive Care Unit was unusual and full of complications. She received very high doses of insulin for her age and weight, with a very poor response to insulin and resistant persistent acidosis even after >72 hours of IV insulin therapy.

Metabolic evaluation was done in front of this severe and persistent acidosis, high lactic acid level was found. She was started on large spectrum antibiotics after taking all culture samples, in order to cover an eventual infection. It was difficult to find vein for perfusion, a central line on the femoral vein was performed, but unfortunately 3 days later, she developed a deep and extensive vein thrombosis on this central line. Femoral Vein catheter was then removed urgently, and a Broviac catheter was done with heparin IV administration started urgently.

She started to improve only when she received thiamine intravenous supplement, coenzyme Q10, and L-Carnitin, showing the impact of thiamine as adjunctive therapy in the treatment of DKA and diabetes mellitus.

Mitochondrial disease was then suspected, suspicion of MELAS (mitochondrial encephalopathy, lactic acidosis, stroke like episode), which is a common cause of mitochondrial Diabetes disorders, but unfortunately genetic tests still not realized in this patient because of financial issues.

In conclusion, our patient presented a severe combined diabetic ketoacidosis (DKA) and lactic acid acidosis, showing the importance of understanding the pathophysiological mechanisms underlying lactic acidosis in DKA.

Conclusion(s) Genetic tests must be done in this patient in order to rule out an underlying metabolic or mitochondrial disease, as an uncommon but important cause of diabetes mellitus as endocrinopathy.

This case showed the impact of IV Thiamin administration as an adjunctive therapy for DKA leading to faster resolution of acidosis and improving aerobic metabolism.