Brief Answer: Yes this may be related to less tubular absorption of potassium. Detailed Answer: Hello, Thank you for using HCM to post your question. Yes this may be related to less tubular absorption of potassium. It does exist a tubular dysfunction syndrome which is characterized by low blood level of potassium and poliuria (high amount of urine output). I would advice you to contact the specialist and to carry out periodic evaluation of renal function and serum electrolytes. It is important to give adequate amount of liquids and a rigorous electrolyte (potassium) replacement, especially in hot weather and during exercise, to avoid dehydration and functional cardiac abnormalities secondary to potassium imbalance. With regard to diet, your daughter should eat foods with high potassium content such as plums, banana, spinach, cooked liver, etc... Hope this is helpful. Feel free to ask me for further explanations. Kind regards, Dr. Juarda