[Hyperchloremic acidosis in metabolic acidosis with anion gap excess. Comparison with diabetic ketoacidosis].
The occurrence of hyperchloremia during diabetic ketoacidosis (DKA) recovery and the lack of correlation between anion gap excess (delta AG) and bicarbonate deficit (delta TCO2) on admission suggest an hyperchloremic acidosis (HCLA) component. The hypothesis that this phenomenon is not specific of DKA and can occur in other metabolic acidoses with increased anion gap was tested. HCLA component, defined by the ratio delta AG/delta TCO2 less than or equal to 0.80, was evaluated on admission and during therapy in 31 patients with DKA and 53 patients with non diabetic metabolic acidosis (ND-MA). HCLA component prevalence was similar on admission (32 p. 100 for DKA versus 41 p. 100 for ND-MA), but it increased during therapy only in DKA patients (86 p. 100 at 9 h - P less than 0.001). In view of the significant correlation (r = 0.636; P less than 0.001) observed between delta AG/delta TCO2 and creatinine, kidney acid base defense appears clearly in DKA patients: the more severe the volume depletion, the greater the ketone retention and the less prominent the HCLA. This phenomenon seems to be secondary to a large tubular excretion of ketones. In the 53 ND-MA patients no correlation between delta AG/delta TCO2 and creatinine could be found. A transfer of chloride from cells to the extracellular space secondary to intracellular diffusion of lactate ions could explain the HCLA component.