The difference between sodium and chloride is low , the metabolic disorder in the patient would be?

The question mentions that difference between sodium and chloride is low which is mathematically possible if serum chloride increases. Now physiologically speaking Chloride excretion occurs in urine along with ammonium in 1:1 ratio to maintain electroneutrality . If chloride in blood is more it means it was not lost in urine If chloride is not lost, H+ is not lost in form of ammonium Hence there is an increase of H+ in the body leading to Hyperchloremic Metabolic Acidosis This kind of presentation is seen with renal tubular acidosis type 1,2,4: ureterosigmoidostomy: alkali loss in urine.