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A cohort study was performed of children started on the ketogenic diet for intractable epilepsy from 2000 to 2005 (n = 195). Children who developed kidney stones were compared with those without in terms of demographics, urine laboratory markers, and intervention with urine alkalinization (potassium citrate). Thirteen children (6.7%) developed kidney stones. The use of oral potassium citrate significantly decreased the prevalence of stones (3.2% vs 10.0%, P = .049) and increased the mean time on the ketogenic diet before a stone was first noted (260 vs 149 patient-months, P = .29). The prevalence of kidney stones did not correlate with younger age or use of carbonic anhydrate inhibitors (eg, topiramate or zonisamide) but trended toward higher correlation with the presence of hypercalciuria (92% vs 71%, P = .08). No child stopped the diet due to stones; in fact, the total diet duration was longer (median 26 vs 12 months, P < .001). Kidney stones continue to occur in approximately 1 in 20 children on the ketogenic diet, and no statistically significant risk factors were identified in this cohort. As oral potassium citrate was preventative, prospective studies using this medication empirically are warranted.

The ketogenic diet has traditionally been considered an anticonvulsant therapy of last resort, despite excellent efficacy and limited side effects. We hypothesized that the ketogenic diet would have similar results in patients with new-onset epilepsy. A retrospective study was conducted of patients started on the ketogenic diet since 1994. Thirteen of 460 (2.8%) patients were started on the ketogenic diet as early (zero or one prior anticonvulsant) therapy for seizures. Of those remaining on the diet, 60% (6 of 10) had a > 90% seizure reduction at 6 months and 100% (6 of 6) had a > 90% reduction at 12 months. Patients with infantile spasms were as likely to achieve > 50% seizure reduction at 6 months as patients with other seizure types (75% vs 60%; P = .6). The ketogenic diet can be a valuable therapy before epilepsy becomes intractable. In the 13 patients reported, efficacy without side effects was achieved similarly to that with patients with intractable epilepsy.

Auditory processing of speech and nonspeech sounds was studied prospectively in two hemidecorticectomy patients (ages 10-11 years) with Rasmussen's syndrome. We tested auditory word recognition under four listening conditions: in quiet, in noise, after acoustic filtering, and dichotically. Recognition of environmental sounds and discrimination of tones and digitized syllables were also tested. Presurgical testing confirmed normal processing of speech and nonspeech, for both patients, under all listening conditon. One year after surgery, both patients demonstrated intact recognition of words and environmental sounds in quiet but impaired word recognition in noise. The left hemidecorticectomy patient also demonstrated impaired recognition of low-pass filtered words. These findings suggest that either hemisphere can process speech or nonspeech sounds in quiet, whereas both hemispheres are needed to process speech in background noise. Hemispheric contributions to processing speech in noise appear to differ, with the left hemisphere compensating for loss of phonologic information and the right hemisphere compensating for increased attention demands.

Seizures during the neonatal period have a broad differential diagnosis, many with a specific treatment and prognosis. In the case reported, a combination of dietary and endocrinologic abnormalities resulted in hypocalcemic seizures, which continued despite aggressive correction of serum ionized calcium levels. Serial electroencephalograms (EEG) performed during the hospitalization were markedly abnormal, and treatment with anticonvulsant drugs was considered given the persistence of seizures despite normalization of serum calcium levels. After 4 days of intravenous calcium administration, the seizure activity resolved, and the patient returned to his normal baseline level of functioning. This case highlights the clinical course of neonatal hypocalcemic seizures, EEG findings in several cases, and possible mechanisms for both hypocalcemic precipitation of seizures and anticonvulsant ineffectiveness.

In a prospective study of the efficacy of the ketogenic diet in children with severe, refractory epilepsy, data were collected on medication changes over 1 year. Cost reductions in medications were calculated over the first year and estimated for a second year. Fifty-seven percent of the children stayed on the diet for 1 year, and 74% of these children had their number of medications reduced. Forty-eight percent of children who stayed on the diet were on no medications at 12 months follow-up. Daily medication costs were reduced by nearly 70%.