Clinical Biochemistry

Question 1

Causes of increased anion gap metabolic acidosis

Answer 1

Endogenous acid load

• DKA
• Starvation ketosis
• LA
• Renal failure

Exogenous acid load (Poisoning with)

• Aspirin : Salicylate
• Methanol : Formate
• Ethylene glycol : Glycolate, Oxalate

Question 2

Diagnosis of LA

Answer 2

Plasma lactate - increases 10x

Normal : 2 mmol/L (20 mg/dl)

Question 3

Types of LA

Answer 3

Type 1
- due to tissue hypoxia –> peripheral generation of lactate

• in circulatory failure & shock

Type 2

• due to impaired MB of lactate
• in liver disease
• drugs : metformin
• toxins

Question 4

Causes of normal anion gap metabolic acidosis

Answer 4

Ingestion or infusion of inorganic acid (therapeutic or poisoning) - NH4CL, HCL

GI bicarbonate loss - diarrhoea, small bowel fistula, urinary diversion procedure

RTA