Moxifloxacin Concentration and Proteomic Analysis of Aqueous Humor in Human Uveitis Associated with Oral Moxifloxacin Therapy

Severe sequelae in bilateral acute iris transillumination syndrome secondary to the use of oral moxifloxacin: a case report

Background

Moxifloxacin is a fourth-generation fluoroquinolone used as a second-line treatment for multiple bacterial infections. Uveitis has been described as an adverse effect related to this medication. Although several case reports have been published describing uveitis and bilateral acute iris transillumination syndrome related to moxifloxacin, we present a unique case of a patient with severe sequelae associated with bilateral acute iris transillumination syndrome secondary to the use of oral moxifloxacin.

Case presentation

A 45-year-old Colombian hispanic female presented bilateral conjunctival hyperemia, decreased visual acuity, blurred vision, photophobia, and ocular pain after 15 days of treatment with systemic moxifloxacin for an upper tract respiratory infection. The patient presented unilateral anterior chamber pigment dispersion, mydriatic and nonreactive pupils, extensive iris transillumination defects, and secondary glaucoma. Blood and aqueous humor tests were negative for infectious and autoimmune diseases. Moxifloxacin-induced bilateral acute iris transillumination syndrome was diagnosed. Permanent sequelae such as ocular pain, photophobia, and focus difficulty secondary to severe bilateral iridian atrophy and inability of synkinetic reflex were left. Additionally, glaucoma was diagnosed, and Ahmed valve implantation was required.

Conclusions

We should be aware of the possible association between moxifloxacin and bilateral acute iris transillumination syndrome. A detailed anamnesis, adequate examination, and laboratory tests are necessary to reach an early diagnosis and treatment to avoid unnecessary therapies. Larger studies should be carried out to understand the pathophysiology, diagnosis, management, and sequelae of the disease.

Protein Biomarkers in Uveitis

The diseases affecting the retina or uvea (iris, ciliary body, or choroid) generate changes in the biochemical or protein composition of ocular fluids/tissues due to disruption of blood-retinal barrier. Ocular infections and inflammations are sight-threatening diseases associated with various infectious and non-infectious etiologies. Several etiological entities cause uveitis, a complex intraocular inflammatory disease. These causes of uveitis differ in different populations due to geographical, racial, and socioeconomic variations. While clinical appearance is sufficiently diagnostic in many diseases, some of the uveitic entities manifest nonspecific or atypical clinical presentation. Identification of biomarkers in such diseases is an important aid in their diagnostic armamentarium. Different diseases and their different severity states release varying concentrations of proteins, which can serve as biomarkers. Proteomics is a high throughput technology and a powerful screening tool for serum biomarkers in various diseases that identifies proteins by mass spectrometry and helps to improve the understanding of pathogenesis of a disease. Proteins determine the biological state of a cell. Once identified as biomarkers, they serve as future diagnostic and pharmaceutical targets. With a potential to redirect the diagnosis of idiopathic uveitis, ocular proteomics provide a new insight into the pathophysiology and therapeutics of various ocular inflammatory diseases. Tears, aqueous and vitreous humor represent potential repositories for proteomic biomarkers discovery in uveitis. With an extensive proteomics work done on animal models of uveitis, various types of human uveitis are being subjected to proteome analysis for biomarker discovery in different ocular fluids (vitreous, aqueous, or tears).

Bilateral acute anterior uveitis and iris atrophy caused by moxifloxacin

A 56-year-old paramedic was admitted to hospital and treated for severe pneumonia. Shortly after initiating antibiotic treatment (including moxifloxacin), he developed bilaterally painful eyes and was diagnosed with bilateral acute anterior uveitis (AAU). Three years later, he was referred to the ophthalmology clinic with bilateral iris transillumination suggesting iris atrophy and limited pupillary dilation, indicating iris sphincter muscle paralysis. AAU typically presents unilaterally. An onset of bilateral AAU is unusual and warrants investigation for underlying systemic cause. The fluoroquinolone moxifloxacin has been reported in a limited number of cases as a causative agent of bilateral AAU and iris atrophy. This case provides additional supporting evidence that moxifloxacin may cause degradation of collagen and iris muscle in the eye, as well as elsewhere in the body, such as in blood vessels. Additionally, we present novel anterior segment ocular imaging (using optical coherence tomography) demonstrating the ability to detect iris atrophy using non-invasive imaging.