Page 199 - Read Online

well-documented postdiphtheritic complication. The
[4]
increased prevalence of respiratory and gastrointestinal
tract infection and the presence of relatively immature
neural tissue in children may lead to more damaging
neuroimmune responses to infection, explaining
the increased vulnerability during childhood. The
vascular hypothesis proposes that ischemia of roots
of the glossopharyngeal and vagus nerves due to
undetermined causes leads to lower motor neuropathy
manifesting as palatopharyngeal incompetence. [6]

Although isolated palatal palsy is often an idiopathic
disease, establishing this idiopathic nature requires
the exclusion of other possible factors such as
Figure 1: Uvula is deviated to the left side on admission trauma (adenoidectomy or craniofacial trauma),
infection (diphtheria, enteric infection, or poliomyelitis),
neuromuscular disorders (Guillain-Barré syndrome
or motor neuron disease), cranial vessels (internal
carotid artery aneurysm or vascular insult), and
others (syringobulbia, inflammatory disease affecting
various brain stem nuclei and tracts, or tumors,
especially of the posterior fossa, which usually
have a benign course). [5,7] Definitive viral etiologies
for HSV, Coxsackie, Rubeola, HAV, Varicella, and
Epstein-Barr virus have also been established. [4,5,7]
Isolated mononeuropathy generally follows infections
of the respiratory tract like infectious mononucleosis
and parvovirus B-19. [8,9] Cerebral MRI must also be
performed as it allows the exclusion of expansile,
Figure 2: Magnetic resonance imaging of the brain showing no abnormalities
ischemic, or demyelinating lesions of the brainstem.
Thus, to establish the idiopathic nature of this illness
requires exhaustive investigation. Understanding the
somatotropic organization of the vagus nerve and
associated brain nuclei may help to explain the isolated
palatopharyngeal involvement of this condition. In
some rare cases, involvement of the cephalad portion
of the vagus nerve results in isolated palatopharyngeal
palsy. Laryngoscopy provides direct evidence for
[5]
sparing of the vocal cords in this condition as concurrent
vocal cord palsy has been excluded in cases of isolated
acquired velopalatopharyngeal palsy (as in the present
case). [5]

In a systematic review of the literature from 1960 to
2012, only 36 case reports of acquired isolated palatal
Figure 3: Uvula is central and palatal archs are bilaterally symmetrical on the [10]
7th day after admission palsy were found. The cause of this condition remains
undetermined. The disease usually runs a self-limiting
varying degrees of dysphagia, and commonly mimics course with complete recovery within 2-3 weeks in
brainstem lesions. more than 85% of cases. [1,2] Prognosis is excellent.
Although oral glycerol and steroids have been used
The etiopathogenesis of this condition is still elusive. empirically for early recovery, no specific treatment
Two probable mechanisms have been hypothesized is required. [11] Follow-up is mandatory to observe the
to explain its etiopathogenesis: infectious (mainly further course of the disease. Still, establishing the
viral) and vascular. The possibility of an infectious/ benign nature of this disorder requires exhaustive
[3]
postinfectious origin has been well-documented. [4,5] For investigation in order to differentiate it from other
example, acquired isolated palatopharyngeal palsy is a disorders.

190 Neuroimmunol Neuroinflammation | Volume 2 | Issue 3 | July 15, 2015 Neuroimmunol Neuroinflammation | Volume 2 | Issue 3 | July 15, 2015 191