Segmental retinal arteritis in a case of presumed bilateral rifabutin-associated hypopyon uveitis

Purpose

To describe the presentation and clinical course of bilateral hypopyon uveitis and subsequently diagnosed segmental retinal arteritis in an immunocompromised patient treated with intravitreal and systemic antibiotics while on rifabutin therapy for pulmonary tuberculosis (TB).

Observations

A 63-year-old female from West Africa with a past medical history of HIV/AIDS, hepatitis B, and pulmonary TB presented with pain and acute vision loss in the left eye for two days. She was compliant with her treatment regimen for HIV and maintenance therapy for TB including rifabutin. Ocular examination revealed hypopyon uveitis in the left eye (OS). She was treated with broad spectrum systemic antimicrobials, topical prednisolone acetate, and intravitreal injections of vancomycin, ceftazidime, voriconazole, and ganciclovir, with resolution of hypopyon OS in 3 days. Aqueous sampling and systemic workup were unrevealing for causative infection. Two weeks later, she returned with a nearly identical presentation in the right eye (OD) with hypopyon uveitis and was again treated with intravitreal antibiotics. Anterior segment inflammation OD quickly improved after initiation of topical prednisolone acetate 1 % to reveal segmental retinal arteritis on fundus examination. As aqueous sampling was negative for infectious causes, she was diagnosed with presumed rifabutin associated-hypopyon uveitis in both eyes (OU) and segmental retinal arteritis OD, which has not been described previously with rifabutin use. Rifabutin was discontinued and there were no recurrences of uveitis over nine months of follow-up.

Conclusions and importance/implications

Uveitis is an uncommon dose-related toxicity of rifabutin therapy. Segmental retinal arteritis (SRA) may be a rare finding when there is posterior segment involvement, especially in patients with concurrent TB infection. This report highlights a case of delayed bilateral hypopyon-uveitis and expands the presentation to include SRA. Patients treated with rifabutin should be counseled on signs and symptoms of uveitis. Development of rifabutin-associated uveitis may require medication discontinuation.

The Impact of Systemic Medications on Retinal Function

This study will provide a thorough review of systemic (and select intravitreal) medications, along with illicit drugs that are capable of causing various patterns of retinal toxicity. The diagnosis is established by taking a thorough medication and drug history, and then by pattern recognition of the clinical retinal changes and multimodal imaging features. Examples of all of these types of toxicity will be thoroughly reviewed, including agents that cause retinal pigment epithelial disruption (hydroxychloroquine, thioridazine, pentosan polysulfate sodium, dideoxyinosine), retinal vascular occlusion (quinine, oral contraceptives), cystoid macular edema/retinal edema (nicotinic acid, sulfa-containing medications, taxels, glitazones), crystalline deposition (tamoxifen, canthaxanthin, methoxyflurane), uveitis, miscellaneous, and subjective visual symptoms (digoxin, sildenafil). The impact of newer chemotherapeutics and immunotherapeutics (tyrosine kinase inhibitor, mitogen-activated protein kinase kinase, checkpoint, anaplastic lymphoma kinase, extracellular signal-regulated kinase inhibitors, and others), will also be thoroughly reviewed. The mechanism of action will be explored in detail when known. When applicable, preventive measures will be discussed, and treatment will be reviewed. Illicit drugs (cannabinoids, cocaine, heroin, methamphetamine, alkyl nitrite), will also be reviewed in terms of the potential impact on retinal function.

Rifabutin: where do we stand in 2016?

Rifabutin is a spiro-piperidyl-rifamycin structurally closely related to rifampicin that shares many of its properties. We attempted to address the reasons why this drug, which was recently recognized as a WHO Essential Medicine, still had a far narrower range of indications than rifampicin, 24 years after its launch. In this comprehensive review of the classic and more recent rifabutin experimental and clinical studies, the current state of knowledge about rifabutin is depicted, relying on specific pharmacokinetics, pharmacodynamics, antimicrobial properties, resistance data and side effects compared with rifampicin. There are consistent in vitro data and clinical studies showing that rifabutin has at least equivalent activity/efficacy and acceptable tolerance compared with rifampicin in TB and non-tuberculous mycobacterial diseases. Clinical studies have emphasized the clinical benefits of low rifabutin liver induction in patients with AIDS under PIs, in solid organ transplant patients under immunosuppressive drugs or in patients presenting intolerable side effects related to rifampicin. The contribution of rifabutin for rifampicin-resistant, but rifabutin-susceptible, Mycobacterium tuberculosis isolates according to the present breakpoints has been challenged and is now controversial. Compared with rifampicin, rifabutin's lower AUC is balanced by higher intracellular penetration and lower MIC for most pathogens. Clinical studies are lacking in non-mycobacterial infections.

Rifabutin-associated hypopyon uveitis and retinal vasculitis with a history of acute myeloid leukemia

PURPOSE

This study reports a case of bilateral rifabutin-associated uveitis in a child with a history of acute myeloid leukemia.

METHODS

We utilized a clinical case description and brief discussion.

RESULTS

A 17-year-old girl presented with acute bilateral anterior uveitis, a hypopyon in the left eye, and moderate bilateral vitritis. She had a history of acute myeloid leukemia status post-allogeneic hematopoietic stem cell transplant 5 years earlier. She was receiving rifabutin for a biopsy-proven Mycobacterium avium complex pulmonary infection. Work up for infectious and neoplastic etiologies was negative. The uveitis initially responded to topical corticosteroids, but recurred when the drops were tapered. Fluorescein angiography demonstrated diffuse vasculitis of small retinal vessels and cystoid macular edema. After rifabutin was discontinued, the uveitis and vasculitis slowly resolved.

CONCLUSION

Fluorescein angiography demonstrated widespread retinal vasculitis which is a rare manifestation of rifabutin-associated uveitis.

Rifabutin-Associated Panuveitis with Retinal Vasculitis in Pulmonary Tuberculosis

INTRODUCTION

Rifabutin-associated uveitis has been reported frequently in AIDS patients and more rarely in immunocompetent patients. It is characterized clinically by anterior acute uveitis. Only a few poorly documented cases of rifabutin-induced panuveitis with retinal vasculitis have been reported. Here, we report four cases of rifabutin-associated panuveitis with retinal vasculitis.

CASE REPORTS

We describe four patients with active tuberculosis, treated with a multidrug regimen including rifabutin for at least 1.5 months before presentation. The first patient was immunocompetent, the three others had AIDS and were undergoing triple anti-HIV therapy. Three patients were women with a low body weight. All four patients presented with panuveitis and retinal vasculitis. Interruption of the drug rapidly reduced the ocular inflammation in all cases.

CONCLUSION

Four cases of rifabutin-associated panuveitis with retinal vasculitis are reported in patients with active pulmonary tuberculosis. Immunogenicity of Mycobacterium tuberculosis as well as the very low weight of the patients might be implicated in the development of this unusual form of rifabutin-associated uveitis.

Anterior Segment and External Ocular Disorders Associated with Human Immunodeficiency Virus Disease

The eye is a common site for complications of human immunodeficiency virus (HIV) infection. Although cytomegalovirus retinitis remains the most prevalent of the blinding ocular disorders that can occur in individuals with the acquired immunodeficiency syndrome (AIDS), several important HIV-associated disorders may involve the anterior segment, ocular surface, and adnexae. Some of these entities, such as Kaposi sarcoma, were well described, but uncommon, before the HIV epidemic. Others, like microsporidial keratoconjunctivitis, have presentations that differ between affected individuals with HIV disease and those from the general population who are immunocompetent. The treatment of many of these diseases is challenging because of host immunodeficiency. Survival after the diagnosis of AIDS has increased among individuals with HIV disease because of more effective antiretroviral therapies and improved prophylaxis against, and treatment of, opportunistic infections. This longer survival may lead to an increased prevalence of anterior segment and external ocular disorders. In addition, the evaluation and management of disorders such as blepharitis and dry eye, which were previously overshadowed by more severe, blinding disorders, may demand increased attention, as the general health of this population improves. Not all individuals infected with HIV receive potent antiretroviral therapy, however, because of socioeconomic or other factors, and others will be intolerant of these drugs or experience drug failure. Ophthalmologists must, therefore, still be aware of the ocular findings that develop in the setting of severe immunosuppression. This article reviews the spectrum of HIV-associated anterior segment and external ocular disorders, with recommendations for their evaluation and management.

Ocular association of HIV infection in the era of highly active antiretroviral therapy and the global perspective

Ocular involvement is a common complication of HIV infection. Since the late 1990s, widespread use of highly active antiretroviral therapy (HAART) has altered the spectrum, and reduced the incidence of ocular involvement in developed countries. The incidence of the most common ocular opportunistic infection, cytomegalovirus retinitis, has decreased tremendously. However, immune recovery uveitis secondary to HAART has emerged as a frequent visually threatening condition. Early diagnosis and treatment with periocular steroids is helpful in minimizing visual loss. Clinicians should also be aware that certain antimicrobial agents used to treat opportunistic infections in HIV-positive patients are associated with potentially serious ocular side effects. In developing countries, where most of the world's 40 million HIV-positive patients live, the spectrum and incidence of ocular involvement differ from those in developed countries. The lack of HAART availability is among the many causes of these differences, which may include nutritional factors, basic medical care availability and the levels of exposure to different infectious agents. These factors add to the already challenging task of treating ocular complications and preventing blindness in HIV-positive patients in developing countries.

Corneal Endothelial Deposits Associated with Rifabutin Use

PURPOSE

The aim of this study was to report on the possible development of corneal endothelial deposits resulting from the use of rifabutin.

METHODS

Case series consisting of 3 patients treated with rifabutin were retrospectively studied. Two of the patients were infected with human immunodeficiency virus. A corneal and external disease specialist performed a complete ophthalmologic exam and obtained medical histories of the patients.

RESULTS

All cases developed corneal endothelial deposits after previous use of rifabutin. The deposits were bilateral, yellow-white colored, stellate, and mainly peripheral.

CONCLUSIONS

In these 3 cases, the unique positive ocular finding was corneal endothelial deposits, which may be related to the use of rifabutin.

Immune recovery uveitis in AIDS patients with cytomegalovirus retinitis treated with highly active antiretroviral therapy in Venezuela

PURPOSE

To determine the characteristics of immune recovery uveitis (IRU) in acquired immunodeficiency syndrome (AIDS) patients with inactive cytomegalovirus (CMV) retinitis who responded to highly active antiretroviral therapy (HAART) in a Venezuelan population.

METHODS

We examined 34 patients (50 eyes) with AIDS (HAART responders) and healed CMV retinitis. Patients were observed for a median of 19.3 months following an increase in the CD4 cell count. Ten eyes were treated with sub-Tenon space corticosteroid injections. An age-matched control group of patients with healed CMV retinitis who did not have IRU (30 eyes of 20 patients) was included to compare CMV surface area and complications.

RESULTS

We found that 12 (37.5%) of 32 HAART responders developed IRU (18 eyes). The clinical findings of these 18 eyes with IRU are presented. The clinical spectrum of inflammation included vitritis, macular edema, epiretinal membranes, anterior uveitis, macular hole, retinal detachment with proliferative vitreoretinopathy, and cataract. Eyes with IRU had a mean CMV surface area of 31.7%. However, eyes without IRU (control group) had a mean CMV surface area of 35% (P = 0.41). Periocular treatment resulted in vision improvement (in 90% of eyes) without reactivation of retinitis.

CONCLUSIONS

Symptomatic IRU developed in a significant number of patients with CMV retinitis following successful HAART in a Venezuelan population. CMV surface area does not seem to be a risk factor for the development of IRU. Eyes with IRU respond favorably to antiinflammatory therapy without reactivation of retinitis.

Retinal dysfunction and anterior segment deposits in a patient treated with rifabutin

PURPOSE

To describe the clinical and electrophysiological findings in a young boy with decreased vision possibly due to retinal damage by rifabutin.

METHODS

An 8-year-old boy with osteomyelitis was referred due to visual disturbance. During a period of 4 years, the boy was examined six times with electroretinography. Ophthalmological examination included testing of visual acuity, slit-lamp inspection, fundus inspection, fundus photography and kinetic perimetry. Two electrophysiological methods were performed for objective evaluation of retinal function, namely full-field electroretinography and multifocal electroretinography.

RESULTS

We found a slightly reduced visual acuity, a slowly increasing amount of yellow-white deposits on the posterior surface of the cornea and on the anterior part of the lens, a normal fundus appearance, and normal visual fields. However, the electroretinogram was abnormal on several occasions during therapy with rifabutin, but returned to normal 3 months after withdrawal of the medication. The multifocal electroretinogram returned to normal after the full-field electroretinogram had done so. The anterior chamber deposits still remain.

CONCLUSION

Long-term treatment with rifabutin may have a reversible and previously undescribed side-effect on retinal function. The drug may also accumulate irreversibly on the posterior surface of the cornea and on the anterior surface of the lens. We suggest that objective evaluation of retinal function with electrophysiological methods should be performed in patients with visual disturbance during treatment with rifabutin.