Repeated Medical PG Question- 33

A 25 year old male patient presents with ingestion of antifreeze solution.His arterial blood has analysis report is as follows : 

PH = 7.20
Anion gap = 15
PCO2 = 25
HCO3 = 10 

Most likely diagnosis ?

A. High Anion gap metabolic acidosis

B. Normal Anion gap metabolic acidosis

C. Both A and B

D. None

Answer is C-> Both

• anion gap =15 (high)
• Difference in anion gap : 15-10= 5
• Difference in HCO3 levels : 25-10=15

As difference in HCO3 levels is more than that of anion gap , this is a case of High anion gap metabolic acidosis + compensatory respiratory alkalosis + normal anion gap metabolic alkalosis.