Ask-Upmark kidney in a girl with neurofibromatosis type 1.

Ask-Upmark kidney (AUK) is a scarred segment of the kidney, characterized by formation of primitive tubular and glomerular structures, and sporadically diagnosed as a cause of hypertension (HTN). A 6-year-old girl with neurofibromatosis type 1 (NF1) and moyamoya syndrome had severe HTN. Based on past history, she had HTN at the age of 1.5 years. Laboratory examination revealed slightly elevated plasma and renal venous renin activity without lateralization. No evidence of pheochromocytoma, or coarctation of the aorta was found. Contrast-enhanced computed tomography (CT) showed an area of hypoperfusion in the upper and middle poles with reduced size of the right kidney. The results of dimercaptosuccinic acid scintigraphy were in accordance with those of contrast-enhanced CT. Selected renal arteriography revealed a paucity of peripheral vascularity in the same parts of the right kidney. In the absence of a history of urinary tract infection and vesicoureteral reflux by cystography, we presumed that the severe HTN may be due to segmental hypoplasia of the kidney, AUK, with a possible contribution from NF1. Although renal artery stenosis and pheochromocytoma are well-known causes of HTN in NF1, this case demonstrates that HTN can be caused by AUK in patients with NF1.

Crystalline nephropathy caused by tosufloxacin.

A 14-year-old girl was treated for 3 days with tosufloxacin (450 mg twice a day) for acute bronchitis and then developed acute kidney injury. Renal ultrasound showed enlarged kidneys without hydronephrosis. Urinalysis indicated drug crystal casts (2-3/HPF), consistent with drug-induced crystalline nephropathy. The patient recovered gradually with i.v. hydration and discontinuation of tosufloxacin, leading to the diagnosis of tosufloxacin crystalline nephropathy. Medical practitioners should be aware that crystalline nephropathy can occur in pediatric patients receiving tosufloxacin.

[Cervical myelopathy associated with os odontoideum after botulinum toxin treatment in a patient with cerebral palsy].

Os odontoideum is a separate ossicle from the odontoid process from the body of the axis by a variable transverse gap. A boy with cerebral palsy probably due to prematurity and kernicterus, was treated with botulinum toxin for continuous dystonic movements at the age of 3.5 years. Although botulinum toxin appeared to be remarkably effective for relaxing hypertonia, abnormal frequent anterior flexion of the neck remained. Because of feeding difficulty and frequent aspiration episodes, additional botulinum toxin therapy was discontinued. His condition seemed to be stable and he could walk with support at age 7. However, at age 8, he presented with decreased movement of the extremities and bilateral ankle clonus. Radiographic examination of the cervical spine revealed cystic lesion and os odontoideum. With cervical posterior fixation, the patient made a good recovery. Although athetoid cerebral palsy displays an increased risk of cervical myelopathy, os odontoideum is rare in early childhood. The frequent dynamic stress of the neck due to an unbalanced, persistently contracted state and sudden collapse, possibly attributed to botulinum toxin therapy, might have led to atlantoaxial instability and os odontoideum.