The pathogenesis of anosognosia for hemiplegia (AHP) remains unclear, but recent theories have involved global cognitive deterioration or more modular mechanisms.1-3 Persistent AHP is usually found in left hemiplegic patients with large right frontoparietal cortical lesions or with subcortical damage, specially to the perithalamic regions.1 2 4 Anosognosia for motor deficit is exceptionally reported in “non-hemispheric” damage and is related to a simultaneous confusional state.5 6 We report a patient with severe and prolonged anosognosia for left hemiplegia occurring after a right pedonculopontine haemorrhage. A possible explanation for this AHP might be the association of a left complete somatosensory deficit secondary to brainstem lesion with a global cognitive impairment due to histologically established Alzheimer’s disease. This case, to our knowledge, is unique in the literature and it raises interesting questions on the origin of AHP.

An 83 year old right handed woman was admitted to hospital because she was found confused with a left hemiplegia. She had an history of hypertension treated with a salidiuretic. She had lived alone since the death of her husband, 15 years ago, and was taking good care of herself, despite a moderate impairment of memory for recent events noticed by her daughter since the past two years. On admission, she was lethargic with a blood pressure of 185/105 mm Hg, a complete proportional left motor and sensory deficit, a discrete right peripheral facial paresis, a conjugate gaze deviation to the left, and swallowing difficulties. Brain CT showed a right lateralised pontine haemorrhage. The mental confusion decreased progressively and disappeared at the end of the second week after onset, allowing a full participation in examination. During the third and fourth weeks after onset, the left hemiplegia remained stable. The patient was unable to detect any type of sensory …