To the Editor: I have read with interest the paper of Dr. Faigel (Faigel, H. C.: Amer J Dis Child 107:277, 1964.) on congenital cysts of the renal medulla. I will only make a short comment on the diagnosis in this case asking whether the author has considered the possibility that this could be a case of "juvenile nephronophthisis", a disease originally described by Fanconi et al. The description of the histological findings is somewhat suggestive of this disease, the characteristic lesions of which have been investigated by Ivemark et al.
This disease is characterized by azotemia, hypotonic polyuria, negative or sparse urinary findings, and normal blood pressure. The patients are often admitted for such reasons as anemia, high sed rate or stiffness (hypocalcemia). Nothing is mentioned in Dr. Faigel's paper about polyuria and polydipsia but in all our cases, this symptom was revealed only upon direct interrogation. Some observations