In a patient with diabetes insipidus lacking ADH, which consequence follows regarding the kidney's countercurrent multiplier system?

💡 Explanation

Without ADH, the collecting duct's permeability to water decreases, impairing water reabsorption driven by the osmotic gradient. The countercurrent multiplier establishes this medullary gradient; therefore, the impaired water reabsorption weakens the gradient rather than increasing sodium reabsorption or urine osmolarity.

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