Excellent response to benzocaine spray in an 8-year-old African female with idiopathic palato-pharyngo-laryngeal myoclonus: a case report.

BACKGROUND

Palato-pharyngo-laryngeal myoclonus (PPLM) is a rare condition characterized by involuntary rhythmic movements of the muscles of the palate, larynx, and pharynx. It may be idiopathic or associated with other neurological deficits such as cerebrovascular accidents (CVA). In this article, we present a unique case of idiopathic PPLM which unexpectedly showed an excellent complete response to benzocaine, which is very exceptional.

CASE PRESENTATION: A clinical examination of an 8-year-old African (Somalian) female suggested the diagnosis of PPLM. An ultrasound imaging (US) as well as laryngoscopy with 15% benzocaine spray showed no associated abnormalities but demonstrated myoclonic spasms. The myoclonic spasms and symptoms unexpectedly subsided after the application of benzocaine. The myoclonus recurred after 5 hours and subsequently subsided following the administration of benzocaine. A further recurrence occurred after 13 hours; however, this latest episode demonstrated reduced frequency and severity after each application, ultimately resolving completely with no recurrence observed within 3 days of admission following each administration of benzocaine (Please refer to Graphical Abstract).

CONCLUSION

All cases of palatal myoclonus (PM) or PPLM should be subjected to a thorough neurological evaluation to exclude any lesional etiologies associated with PPLM. While the prognosis for idiopathic PPLM is generally benign, the notable complete response of our patient to benzocaine spray merits further discussion. Additionally, further research is essential to elucidate the underlying mechanisms and to develop effective management strategies.