Download THIOTHIXENE-INDUCED TOXIC MACULOPATHY

THIOTHIXENE-INDUCED TOXIC MACULOPATHY
Grace Lim, OD
Nadia Zalatimo, OD, FAAO
Manchester VAMC, NH
Abstract:
Thiothixene is an antipsychotic medication similar to piperazine
phenothiazines. Antipsychotic agents are retinotoxic and can produce blur,
dyschromatopsia, constricted fields, abnormal ERG, nyctalopia, and pigment
retinopathy.
Regular eye examinations are important to identify early
maculopathy.
Outline:
I. Case History
a. Pt demographics: 62 year old white man
b. Chief complaint: Decreased vision OS>OD
c. Ocular history:
Unremarkable
d. Medical history:
Schizophrenia, Hypertension, Hyperlipidemia
Nicotine Dependency, Backache
e. Medications:
Thiothixene HCL 25mg, Lisinoprl 20mg,
Nicotine Polacrilex 2mg, as needed
f. Social history:
Long history of smoking
II. Pertinent Clinical Findings
a. Clinical:
Distance visual acuity: OD 20/40, OS 20/200, No improvement on
pinhole
Pupils: 3mm OD, OS, round, reactive, No APD
Color vision: OD 9/14, OS 10/14 with Ishihara plates
Biomicroscopy: Unremarkable OD, OS
Goldmann Applanation Tonometry: OD:16.0 mmHg, OS:18.0 mmHg
@ 1:00pm
Dilated fundus examination:
Lens: Trace Nuclear sclerosis OU
Vitreous: Clear OU
Optic Nerve: 0.25 with healthy rim tissue OD, OS
Macula: OD: Juxtafoveal atrophy with hyperpigmentation involving
the fovea
OS: Diffuse, atrophic RPE changes
No hemorrhage, fluid, exudate OD, OS
Vessels: 2/3 A/V OU
Periphery: flat and intact 360 degree OU
b. Fundus photographs of macula OD, OS, as described above
c. Fundus fluorescein angiography: Extensive RPE window defects
with late staining OD, OS
d. OCT: Extensive RPE window defects with no fluid OD, OS
III. Differential diagnosis
a. Primary: Toxic Maculopathy secondary to thiothixene
b. Others: Gyrate atrophy, Bietti’s crystalline dystrophy, choroideremia,
Age Related Macular Degeneration
IV. Diagnosis and discussion
a. Toxic Maculopathy secondary to thiothixene
The fundus presentation of uniform, bilateral, diffuse pigmentary
maculopathy in the context of a 30 year history of thiothixene use
which was suggestive of toxicity. The patient has been treated for
schizophrenia with thiothixene for more than 30 years. Further
testing with FFA and OCT showed characteristic changes from
medication toxicity. Such changes will be discussed and visually
presented.
V. Treatment, management
a. Discontinuation of thiothixene was recommended
b. Smoking cessation was advised
c. ARED supplementation without beta carotene was recommended
d. Daily monitoring with Amsler grid in each eye was recommended
e. Blood pressure and cholesterol control was stressed
f. Eye examination every 6 months was recommended
g. Bibliography:
Ryan, S.J. “Drug Toxicity of the Posterior Segment.” Retina, 4th
ed., vol. 2, Philadelphia; Elsevier/Mosby, 2006:1839-1856.
Gass, J. Donald. “Thioridazine (Mellaril) Retinopathy.” Stereoscopic
Atlas of Macular Diseases: diagnosis and treatment. 4th ed., vol 2,
St. Louis; Mosby, 1997:779
Toler, S.M. Oxidative stress plays an important role in the
pathogenesis of drug-induced retinopathy. Exp.Biol.Med.
(Maywood). 229:607-615, 2004.
Toler, S.M. Invited review: fluphenazine augments retinal oxidative
stress. J Ocul Pharmacol Ther. 21(4):259-265, 2005.
Fornaro, P., Calabria, G.,Corallo, G., et al. Pathogenesis of
degenerative retinopathy induced by thioridazine and other
antipsychotics: A dopamine hypothesis. Doc. Ophthalmol.
105:41-49, 2002.
Lee, M.S., and Fern, A.I. Fluphenazine and its toxic maculopathy.
Ophthalmic Res. 36:237-239, 2004.
Shah, G.K., Auerbach, D.B., Augsburger, J.J., Savino, P.J., Acute
Thioridazine retinopathy. Arch Ophthalmol. 116(6):826-827, 1998.
Borodoker, N., Del Priore, L.V., Carvalho, C.A., Yannuzzi, L.A.,
Retinopathy as a result of long-term use of Thioridazine. Arch
Ophthalmol. Vol. 120:994-995, 2002.
Blair, J.R., Mieler, W. F., Retinal toxicity associated with commonly
encountered systemic agents. Int Ophthalmol Clin. 35(4):137-156,
1995.
Kempen, J.H. Drug-induced maculopathy. Int Ophthalmol Clin.
39(4):67-82, 1999.
VI. Conclusion:
Optometrists should consider toxic maculopathy in patients taking
antipsychotic medications in the phenothiazine-class. Such patients
should have regular eye examinations including fundus photography to
identify early toxic retinal changes and prevent vision loss from toxic
maculopathy. Patients taking phenothiazine-related medications should
be educated about potential retinal toxicity and advised to monitor for
vision changes regularly with the amsler grid.