Naslov
CONGENITAL MYASTHENIC SYNDROME

Autori
Barišić, Nina

Vrsta, podvrsta i kategorija rada
Sažeci sa skupova, sažetak, pregledni

Skup
Muscular dystrophies: from genes via muscles to the clinical facts

Mjesto i datum
Ljubljana, Slovenija, 14.03.2003. - 16.03.2003

Vrsta sudjelovanja
Pozvano predavanje

Vrsta recenzije
Međunarodna recenzija

Ključne riječi
Congenital myasthenic syndrome; molecular genetics; electrophysiology; acetylcholine receptors

Sažetak
CMS are genetically determined disorders affecting safety margins of neural transmission at presynaptic, postsynaptic and synaptic level. Diagnosis of CMS is made on clinical symptoms including fatiguable muscle weakness since infancy or childhood, decremental EMG response and negative AChR antibodies. In some CMS the onset is delayed, weakness and EMG abnormalities appear intermitently in restricted distribution. Investigations of CMS include light and electronmicroscopy of EP morphology, electrophisology of EP function , currents and potentials, molecular genetic analysis and expression studies with mutatnt molecule. Presynaptic forms include CMS associated with episodic apnea and decreased ACh resynthesis and vesicular filling, CMS with paucity of synaptic vesicles, and CMS with EMG findings resembling to Lambert-Eaton syndrome. Presynaptic CMS are associated with recessive ChAT (Cholinacyltransferase) gene mutations. The synaptic form is caused by mutation of collagenic tail subunit of AChE gene. However the most of CMS are postsynaptic, mostly caused by mutations of AChR subunits. Various mutations nonsense or frame shifting mutations cause CMS by decreased or absent protein expression and are inherited in autosomal recessive traits. Rapsyn mutations cause primary endplate AChR deficiency. In contrast, missense mutations of the epsilon-AChR subunit gene have been reported in CMS. In general, channel pore lining domains may alter the electrophysiogical properties of the channel resulting in what is known as the Slow Channel Congenital Myasthenic Syndrome (SCCMS). SCCMS are usually inherited as autosomal dominant traits. Delayed pupillary response and hand and wrist extensor weakness are regarded as clinical clues indicating SCCMS.

Izvorni jezik
Engleski

Znanstvena područja
Kliničke medicinske znanosti

POVEZANOST RADA