[Hysterical mutism]

Conversion disorders comprise many clinical pictures, including hysterical mutism. Hysterical mutism has emerged as a clinical entity that remains difficult to diagnose, and whose treatment is poorly codified. Hysterical mutism is a disorder of the vocal function without changing the integrity of the body, resulting in loss of voice. Identified at all times, hysterical mutism entered the medical field in the late nineteenth century, under the direction of Jean-Martin Charcot (Salpêtrière School). Since then, although the disorder has emerged as a clinical entity, it remains little known.

A systematic review of the literature. We performed electronic literatures search of relevant studies using Medline, SUDOC, and BIUM. Search terms used were mutism, functional aphonia, conversion disorder, hysteria.

The epidemiology of hysterical mutism is difficult to assess. The first limitation is the lack of consensensual diagnostic criteria. An estimate of its frequency may be advanced through registries consultation of otolaryngology-head and neck surgery. Through a literature review, emerges a rare disorder, about 5% of functional dysphonia. The sex-ratio is in favour of women. Regarding age of onset of disorder, functional aphonia mainly concerns adults with an average around the age of 30-40 years. The onset of the disorder typically involves a sudden onset and a recent stressful event. The duration of the disorder is difficult to specify. It appears that this dysfunction is rapidly reversible and that the majority of patients are in remission of this disorder within three months. The recurrence of dysfunction seems to be frequent. The existence of psychiatric comorbidity did not appear to be the rule. The natural history of this disorder is not known making it tricky to evaluate the efficiency of therapeutic approaches.

Today the term hysterical mutism does not appear as an entity in either international classification. It belongs to the category of conversion disorder in the Diagnostic and Statistical Manual of Mental Disorders (DSM-IV-TR). Identified as a medical entity described by the school of the Salpêtrière, this disorder has raised little interest. The medicalization of the condition remains difficult because of the importance of stigma associated with it, which contributes to the rejection rather than support of patients with mutism. To better understand this disorder and improve the care of patients who suffer, renewed interest is warranted.