Subacute sclerosing panencephalitis presenting as Leonhard's speech-prompt catatonia

A woman aged 20, first presenting with what appeared to be hysterical blindness as part of the syndrome of hysterical pseudo-dementia, soon showed the picture of speech-prompt catatonia, one of the subtypes of chronic schizophrenia described by Karl Leonhard. However, within a short time the neurological, EEG and laboratory findings indicated that the condition was one of subacute sclerosing panencephalitis.