Yusuke Koteda

Benign infantile convulsions associated with mild gastroenteritis: A retrospective study of 39 cases including virological tests and efficacy of anticonvulsants

Benign convulsions associated with mild gastroenteritis (CwG) are a commonly observed disorder in Asia, especially in infants and seniors. Here, we describe a retrospective study about the clinical features of CwG in 62 children hospitalized at St. Marys Hospital (Kurume City, Japan) between January 1, 2000 and March 31, 2006, and further evaluate the efficacies of various anticonvulsant treatments for patients with CwG due to either rotavirus or norovirus. Causative diarrheal viruses were detected in 71% of the fecal specimens tested; 30 patients were positive for rotavirus, nine patients were positive for norovirus, two patients were positive for sapovirus, two patients were positive for adenovirus, and one patient was positive for coxackievirus A4. The age of onset for patients with norovirus-positive CwG (16.7+/-2.7 months) was significantly lower than that of patients with rotavirus-positive CwG (23.0+/-8.7 months). The duration of the seizures due to norovirus infection (11.8+/-12.0 h) was significantly longer than that due to rotavirus infection (4.9+/-5.7 h). There were no significant differences between the two groups with regard to the results of blood chemistry analysis, including the concentrations of serum electrolytes, blood glucose levels, and liver function tests. In this preliminary study, the duration of seizures in patients with CwG due to norovirus that was treated with carbamazepine was significantly shorter than the duration of seizures in the patients treated with another anticonvulsant (phenobarbital). Further randomized controlled studies are required to clarify the efficacies of the various anticonvulsants for patients with CwG.

Portal-systemic encephalopathy after Fontan-type operation in patient with polysplenia syndrome

An 18-year-old patient, who had polysplenia and single ventricle, presented with altered mental status 9 years after a Fontan-type operation and pacemaker implantation. He underwent replacement of common atrioventricular valve and aortic valve plasty 1 year previously and has been placed on multiple medications including beta-blocker for his poor ventricular function. Blood chemistry revealed hyperammonemia of 2420 microg/l as a cause of this altered mental status disturbance. Superior mesenteric arteriography revealed large portal-systemic shunts in venous phase as a cause of hyperammonemia. To control blood ammonia level, we placed him on low protein diet, oral polymixin B, and lactulose instead of closing shunt with device. This case illustrates that portal-systemic shunt may result in hyperammonemia leading to altered mental status long after a Fontan-type operation.