Myogenic transcription factors with a basic helix-loop-helix (bHLH) such as MYOD, myogenin, MRF4, and MYF5 contribute to muscle differentiation and regulation. The MYF5 gene located on chromosome 12 encodes for myogenic factor 5 (MYF5), which has a role in skeletal and extraocular muscle development and rib formation. Variants in MYF5 were found to cause external ophthalmoplegia with rib and vertebral anomalies (EORVA), a rare recessive condition. To date, three homozygous variants in MYF5 have been reported to cause EORVA in six members of four unrelated families. Here, we present a novel homozygous MYF5 frameshift variant, c.596dupA p. (Asn199Lysfs*49), causing premature protein termination and presenting with external ophthalmoplegia, ptosis, and scoliosis in three siblings from a consanguineous family of Pakistani origin. With four MYF5 variants now discovered, genetic testing and paediatric assessment for extra-ocular features should be considered in all cases of congenital ophthalmoplegia.

The purpose of this case report is to report a case of congenital idiopathic enlargement of extraocular muscles. A four-month-old girl showed limitation of adduction and supraduction in the right eye. A computerized axial tomography (CAT) scan revealed hypertrophy of the lateral rectus muscle and inferior rectus muscle of the right eye. Thyroid hormone and antibody levels were normal. No inflammatory findings on magnetic resonance imaging (MRI). A traction test under general anesthesia revealed a strong limitation of supraduction and a mild limitation of adduction. Therefore, the inferior rectus muscle was recessed 4.5 mm at the age of six months. A partial biopsy of the inferior rectus showed no inflammatory cell infiltration. After the first surgery, the patient\'s limitation of supraduction improved, but the limitation of adduction persisted. So, a 5 mm recession of the right lateral rectus muscle was added at one year and one month. However, the hypertropia of the sound eye became stronger after treatment of amblyopia. Because of the strong limitation of supraduction, tenotomy of the inferior rectus was performed at the age of six years. Postoperatively, no impairment of infraduction occurred, and the limitation of supraduction was mildly improved. Since the findings on MRI were not changed through our observation period, we concluded that the patient had idiopathic external ophthalmoplegia.

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Inherited deficiency of thymidine phosphorylase (TP), encoded by TYMP, leads to a rare disease with multiple mitochondrial DNA (mtDNA) abnormalities, mitochondrial neurogastrointestinal encephalomyopathy (MNGIE). However, the impact of TP deficiency on lysosomes remains unclear, which are important for mitochondrial quality control and nucleic acid metabolism. Muscle biopsy tissue and skin fibroblasts from MNGIE patients, patients with m.3243 A > G mitochondrial encephalopathy, lactic acidosis and stroke-like episodes (MELAS) and healthy controls (HC) were collected to perform mitochondrial and lysosomal functional analyses. In addition to mtDNA abnormalities, compared to controls distinctively reduced expression of LAMP1 and increased mitochondrial content were detected in the muscle tissue of MNGIE patients. Skin fibroblasts from MNGIE patients showed decreased expression of LAMP2, lowered lysosomal acidity, reduced enzyme activity and impaired protein degradation ability. TYMP knockout or TP inhibition in cells can also induce the similar lysosomal dysfunction. Using lysosome immunoprecipitation (Lyso- IP), increased mitochondrial proteins, decreased vesicular proteins and V-ATPase enzymes, and accumulation of various nucleosides were detected in lysosomes with TP deficiency. Treatment of cells with high concentrations of dThd and dUrd also triggers lysosomal dysfunction and disruption of mitochondrial homeostasis. Therefore, the results provided evidence that TP deficiency leads to nucleoside accumulation in lysosomes and lysosomal dysfunction, revealing the widespread disruption of organelles underlying MNGIE.

Acute motor axonal neuropathy (AMAN) is a variant of Guillain-Barré syndrome (GBS), characterized by acute areflexic flaccid quadriparesis with motor axonal changes and absence of demyelinating findings in electrophysiological studies. A 30-year-old man presented with acute onset flaccid type of weakness involving all four limbs, along with drooping of eyelids. Examination revealed ptosis with restricted horizontal and vertical eye movements. Spinomotor system examination revealed acute flaccid areflexic quadriparesis. Nerve conduction studies (NCS) showed features suggestive of motor axonal neuropathy changes. Cerebrospinal fluid (CSF) revealed albuminocytological dissociation. The diagnosis of AMAN was made, and the patient was treated with intravenous immunoglobulin (IVIg). His weakness gradually improved over 1 month, with partial improvement in ptosis and eye movements. This case highlights the occurrence of ophthalmoparesis in the AMAN variant of GBS. The presence of ophthalmoparesis and areflexia makes it necessary to exclude Miller-Fisher syndrome. But, the presence of axonal changes in nerve conduction study and the profound weakness with negative serum anti-GQ1b antibody profile, supports the diagnosis of AMAN. How to cite this article: Budumuru U, Muralidharan K, Sowmini PR, et al. AMAN with Ophthalmoparesis: A Rare Presentation. J Assoc Physicians India 2023;71(11):103-104.

Herpes zoster ophthalmicus (HZO) is a condition resulting from the reactivation of dormant varicella zoster virus within the sensory nerve ganglion in the ophthalmic branch of the trigeminal nerve. The tell-tale rash along one side of the nerve tract accompanied by pain, a burning sensation, and itching alerts health practitioners on the right path to diagnosis. Conversely, HZO can present with other rarer complications such as intraocular and extraocular manifestations. This case report deals with a seemingly healthy 45-year-old female who developed left abducens nerve palsy within one week of developing a vesicular rash on the same side. Curiously, those afflicted are usually of an advanced age or suffer from an immunocompromised state; this patient however suffered from no other comorbidities nor did she report having been in contact with anyone of a similar affliction. In this case, the classical treatment regime of antivirals and corticosteroids resulted in the complete resolution of the infection and the return of full ocular function. Being able to recognize and appreciate these typical and atypical signs and symptoms of HZO can aid in the further propagation of good outcomes and timely resolutions.

The POLG mutation, a leading cause of mitochondrial diseases, exhibits a wide-ranging age of onset and a complex clinical presentation. We encountered an atypical clinical profile in an elderly man with a POLG mutation, characterised by a stroke-like episode, chronic insomnia and transient oculomasticatory rhythmic movement. History revealed chronic constipation since his 50s and progressive bilateral ophthalmoplegia since his early 60s. Subsequently, he had experienced acute encephalopathy and later developed chronic insomnia. The present neurological examination showed bilateral complete ophthalmoplegia, ptosis, and rhythmic ocular and jaw movements. Imaging indicated findings suggestive of a stroke-like episode and eventual genetic analysis revealed a homozygous missense mutation in the POLG gene. This case expands the clinical spectrum of POLG mutations in individuals over 60 years, showcasing the rare combination of a stroke-like episode, chronic insomnia and oculomasticatory rhythmic movement.

Epstein-Barr virus (EBV) can cause follicular conjunctivitis, keratitis, oculoglandular syndrome, meningitis, and encephalitis. We report a 54-year-old Hispanic male who presented with right pupil-involved complete ophthalmoplegia, orbital and masticatory muscle inflammation, trigeminal enhancement, and new corneal infiltrate highly suggestive of EBV. Labwork was negative except for positive EBV polymerase chain reaction (PCR) in serum. Magnetic resonance imaging (MRI) of his brain and orbits with contrast showed enhancement of the right ganglion of the trigeminal nerve, oculomotor nerve, all extraocular muscles in the right orbit, and right masticatory and temporalis muscles and a right subacute lacunar infarct. The patient was diagnosed with encephalitis and orbital-face inflammation secondary to EBV infection. The patient improved with systemic steroids.

Cerebral venous sinus thrombosis (CVST) is a rare cause of strokes and is most common in younger patients particularly those less than 50 years of age. It is more common in females than in males and is known to be associated with pregnancy, puerperium, oral contraception, congenital and acquired thrombophilia, and malignancy. Less commonly, it has been shown to be associated with infections and more recently has been found to be associated with COVID-19 infection with thrombocytopenia and the COVID-19 vaccine AstraZeneca. Rare cases have been reported in association with varicella zoster virus (VZV) infection (chickenpox) and its reactivated version of herpes zoster virus (HZV) infection (shingles). We report the case of a 68-year-old lady with herpes zoster ophthalmicus ophthalmoplegia who developed cerebral venous thrombosis (CVT).

We report a case of isolated left abducens nerve palsy accompanying a right thalamic infarct. The patient, a 43-year-old Malay male with newly diagnosed hypertension, diabetes mellitus, and dyslipidemia, initially reported binocular diplopia on left lateral gaze persisting for five weeks. Subsequently, he experienced acute left-sided body weakness and slurred speech for over one day. Clinical examination revealed restricted left eye lateral gaze (-3) with no relative afferent pupillary defect. Additionally, decreased power (4/5) was noted in the left upper and lower limbs. Brain magnetic resonance imaging (MRI) revealed restricted diffusion in the right thalamus extending to the right posterior internal capsule, left anterior cingulate gyrus, and left caudate nucleus. The patient was initiated on antiplatelet, antihypertensive, and oral hypoglycemic agents, resulting in symptom improvement. This rare neuroophthalmological finding has not been reported previously.