sudden impolite behavior in a polite girl: a case report.

in this case we present a previously healthy child with sudden behavioral change and acute confusional state (acs). acs is a neurologic emergency. the clinical manifestations of acs are; confused affect, limited verbal response, disturbance in performing orders, some automatism, stable vital signs and absence of tonic-clonic movements and it has a wide range of differential diagnosis which should be assessed by detailed medical history, medical examination and laboratory tests. the only abnormal test found in this patient, was cerebrospinal fluid abnormality, consistent with viral encephalitis.