Final answer:
Increased ammonium chloride in urine suggests acidosis, as the kidneys excrete ammonium to buffer and remove excess hydrogen ions in response to an acidotic state.
Step-by-step explanation:
An increase in the amount of ammonium chloride in the urine most likely indicates acidosis. During acidosis, the body needs to buffer and excrete excess acids. The kidney contributes to this by deaminating glutamine, producing ammonia (NH3), which is then converted to ammonium (NH4+) and excreted in the urine. The excretion of ammonium ions is a response to increased hydrogen ion concentration in the body's fluids, indicating an acidotic state. Notably, during metabolic acidosis, there is typically an increased production of ammonium, while dehydration, another possible cause, is not directly linked to the excretion of ammonium ions.