Horizontal diplopia with right abducens palsy and gaze evoked nystagmus due to pontine lesion in human immunodeficiency virus related cerebral toxoplasmosis

Abstract

AbstractPurpose: This case report will discuss about the diagnostic approach in a rare case of horizontal diplopia with Human Immunodeficiency Virus (HIV) related Cerebral Toxoplasmosis.Methods: The diagnosis was based on history taking, ophthalmologic examinations, vestibular‐ocular reflex (VOR) test, convergence test, nystagmus test, cerebellar function test, serological findings and magnetic resonance imaging (MRI) of head and orbita.Results: A 30 years old man with the main complaint binocular horizontal diplopia since 2 months ago, accompanied by headache, disorder of coordination, balance, speech and also impaired of memory and concentration. There was history of head injury and promiscuity. Visual acuity of both eyes 6/6 with best corrected visual acuity. There were abduction deficit on right eye, abducting nystagmus on left eye, no vestibular‐ocular reflex, no convergence insufficiency and no dysfunction of cerebellar. Immunoglobulin‐G antibodies Toxoplasma >650.0 IU/ml, Cluster Determinant 4 (CD4) T cell 55 cells/μl, and HIV reactive in serological findings. MRI of head and orbita revealed a lesion on pontine tegmentum. Patient was diagnosed with horizontal diplopia with right abducens palsy and gaze evoked nystagmus due to pontine lesion in HIV related cerebral toxoplasmosis.Conclusions: History taking and ophthalmologic examinations are important steps to establish the diagnosis. VOR test can determine the lesion in supranuclear, nuclear or infranuclear. Serological tests and MRI of head and orbita may be helpful in confirming the diagnosis and finding the cause of binocular horizontal diplopia.