Revisiting regression in autism: Heller's dementia infantilis. Includes a translation of Über Dementia Infantilis.

Navakatikyan et al. (2013) dug into 100-year-old medical notes. They looked at kids who lost skills after age three. The team compared these cases to today's rules for childhood disintegrative disorder.

They paid special attention to mood signs that showed up before the big skill loss.

Every file showed the same early story. First came weeks of wild mood swings, crying fits, and fear. Then the child lost language, play, and toilet skills.

This 'affective storm' phase had never been listed as a red flag before.

Hayes (1989) and Wilkinson et al. (1998) show that autism and Rett can look almost identical. Their point: check for hand-wringing and breath-holding so you do not miss Rett.

Alexander's group does not disagree. They simply add a new clue: severe mood swings may come before the motor signs. Use both sets of flags together.

Ganz et al. (2009) found that subtle movement and vocal quirks appear before six months in preserved-speech Rett. Alexander's affective phase shows up later, closer to the actual skill loss. The two papers map different moments on the same downhill track.

If a family says their four-year-old is suddenly angry, clingy, and sleeping poorly for weeks, do not wait for more classic signs. Chart the behaviors daily and fast-track a full developmental work-up. Early clues let you start supports before the child loses speech or self-care skills.