 |
|
Discoloration of Intraocular Lens Subsequent to Rifabutin Use
Arch Ophthalmol. 2002;120:1211-1212.
A 63-year-old woman developed discoloration of the silicone intraocular
lens (IOL) implants in both eyes after receiving 300 mg of rifabutin by mouth,
once daily, for 10 months. Examination revealed a rose color to both
implants, though the patient reported minimal visual deficit. We then investigated
the effect of rifabutin on 3 different common IOL materials and found that
it only affected silicone. Though rifabutin is well known to cause discoloration
of body fluids and soft contact lenses, this case illustrates this process
occurring in IOL implants.
Rifabutin is indicated for prophylaxis against Mycobacterium
avium complex (MAC), which is primarily seen as a coinfection with
human immunodeficiency virus (HIV). Shown to cause discoloration in certain
body fluids, including tears, saliva, and perspiration, rifabutin prescribing
guidelines specifically caution that soft contact lenses may be permanently
stained subsequent to its use.1 However,
to our knowledge, the occurrence in an IOL has not been documented. We describe
a patient who developed a bilateral discoloration of her silicone IOLs.
Report of a Case
A 63-year-old woman had bilateral cataract extractions with silicone
IOL implants (model SI30NB; Allergan Inc, Irvine, Calif) in early 1995. Shortly
after a normal eye examination, she began a 10-month course of 300
mg of rifabutin, by mouth, once daily for chronic pulmonary MAC. At annual
follow-up, both IOLs were noted to be discolored, and rifabutin therapy was
discontinued.
Slitlamp examination revealed a distinct rose-color in both IOLs (Figure 1). The remainder of the examination
was unremarkable, with visual acuity correctable to 20/20 OU.
|
|
|
|
Figure 1. Slitlamp photograph of the lens
shows rose-colored discoloration of the intraocular lens (double arrows) contrasted
against capsular remnants that are not covered by the intraocular lens (single
arrows).
|
|
|
That both IOLs were equally and simultaneously stained is likely to
account for the lack of perceived color shift. No further change in IOL coloration
has been noted since discovery. Thus, the IOLs were not removed.
Comment
Silicone IOL engineering has achieved a high degree of long-term optical
clarity so that reports of decreased clarity have become rare (approximately
0.07%).2 This case represents a potentially
significant effect on the patient's quality of life because the stained lenses
are intraocular.
The rifamycins are recognized as "standard-of-care" drugs against both
tuberculous and atypical mycobacterial infections. Use of these drugs is increasing
because the incidence of MAC has dramatically increased among both HIV-infected
and immunocompetent individuals during the last decade. High rates of increase
are currently being reported in patients older than 50 years.3
Additionally, these drugs are being proven useful against Staphylococcus in orthopedic cases such as after implanted devices
or osteomyelitis.4
Multiple factors point to rifabutin as the most likely cause of staining
here. First, rifabutin has been shown to stain soft contact lenses (typically
silicone). None of the patient's other medications are known to cause discoloration
of body fluids. The timing of the staining, relative to her initiation of
rifabutin therapy, is consistent with rifabutin as the cause. Allergan has
received no similar reports of discoloration (personal communication, G. Kropidlowski,
Allergan Inc). Finally, silicone IOLs placed in a rifabutin solution may dramatically
discolor.
In a laboratory investigation, lenses from 4 different manufacturers
representing 3 materials were immersed for 1 week in a concentrated rifabutin
solution. The discoloration fully penetrated the lens, rather than layering
on as a film (Figure 2). Only the
silicone lenses placed in this solution discolored.
|
|
|
|
Figure 2. Comparison photograph of 4 intraocular
lenses after immersion in concentrated rifabutin solution at 24 hours. A,
Silicon (Allergan SI30NB; Allergan Inc, Irvine, Calif). B, Silicon (AA4204VF;
Staar Surgical, Monrovia, Calif). C, Acrylic (MA30BA; Alcon Surgical, Forth
Worth, Tex). D, Polymethyl methacrylate (UV80F2; Ciba Vision Ophthalmics,
Duluth, Ga). E, Cross section of Allergan lens.
|
|
|
These findings have potential implications for our elderly population,
as many of these individuals may have already received silicone IOLs by the
time that they develop MAC or infection from implantation of orthopedic hardware.
Physicians should be thus cautioned in their use of rifabutin in patients
with silicone IOLs, and that acrylic or polymethyl methacrylate lenses may
be better suited for patients in whom opportunistic infections are likely.
AUTHOR INFORMATION
We wish to thank Linda Ritchie, LPN-COA, Fernando Corrada, CRA, Kemper
Alston, MD, and Fletcher Allen Health Care Pharmacy, Burlington, Vt.
Neither Dr Jones nor Dr Irwin has any proprietary or commercial interest
in any company manufacturing any of the drugs or IOLs named in this case report.
Dr Jones is now a pathology resident at Jefferson Medical College Hospital,
Philadelphia, Pa.
Daniel Fuller Jones, MD;
Alan Emory Irwin, MD
Burlington, Vt
Corresponding author and reprints: Alan Emory Irwin, MD, Division
of Ophthalmology, Fletcher Allen Health Care, UHC Fourth Floor, Burlington,
VT 05405 (e-mail: airwin{at}vtmednet.org).
REFERENCES
1. Physicians' Desk Reference. 53rd ed. Montvale, NJ: Medical Economics Co; 1999:2501-2502.
2. Knight PM. Discoloration of a silicone intraocular lens 6 weeks after surgery
[letter]. Arch Ophthalmol. 1991;109:1494-1496.
FREE FULL TEXT
3. Centers for Disease Control and Prevention Web site. Nontuberculous Mycobacteria Reported to the Public
Health Laboratory Information System by State Public Health Laboratories:
United States, 1993-1996. NTM Report 1999:1-51. Available at: http://www.cdc.gov/ncidod/dastlr/TB/ntmfinal.pdf. Accessed August 30, 2001.
4. Zimmerli W, Widmer AF, Blatter M, Frei R, Ochsner PE. Role of rifampin for treatment of orthopedic implant-related staphylococcal
infections: a randomized controlled trial. JAMA. 1998;279:1537-1541.
FREE FULL TEXT
SECTION EDITOR: W. RICHARD GREEN, MD
 CiteULike  Connotea  Del.icio.us  Digg  Reddit  Technorati  Twitter
What's this?
|
