Rifabutin-Associated Panuveitis with Retinal Vasculitis in Pulmonary Tuberculosis

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.

Hypopyon: Is-it Infective or Noninfective?

Hypopyon usually corresponds to the sedimentation of white blood cells, and it signifies severe intraocular inflammation. This key clinical sign may occur in association with a wide variety of infectious, inflammatory, and neoplastic conditions that may be sight- and, occasionally, life-threatening. A careful history and thorough clinical examination are the cornerstones for orienting the differential diagnosis, identifying the causative agent, and initiating prompt and appropriate treatment. This review outlines the clinical characteristics and management of hypopyon in relation with the underlying causative infectious or noninfectious ocular or systemic diseases.

[Drug-induced uveitis]

In recent years, an increasing amount of attention has been paid to medicinal products as possible risk factors in the development of eye diseases. The frequency of diagnosed drug-induced uveitis is growing yearly, which can be attributed to the appearance of new drugs - biological agents (immune checkpoint inhibitors, BRAF and MEK inhibitors, vascular endothelial growth factor inhibitors, tumor necrosis factor-α inhibitors), as well as systemic bisphosphonates and some antiviral drugs. The time interval between the beginning of the drug use and the appearance of uveitis symptoms varies from several days to months. Common symptoms include eye pain, photophobia, the appearance of floating opacities, and reduced vision associated with active inflammatory changes in the retina and optic nerve and outcomes of those inflammations. Timely diagnosis, cancellation of the drug that caused uveitis and appointment of adequate anti-inflammatory therapy in most cases effectively stops the symptoms of the disease, which determines the relevance of attention to the prevalence, pathogenesis, diagnosis and treatment of drug-induced uveitis.

Pharmacologically induced uveitis

Treatments of numerous systemic and local diseases of different etiologies may be accompanied by an unwanted side effect in the form of uveitis. We inform readers about medications that have the potential to cause uveitis and analyze the strength of association of these medications with uveitis. Subsequently, cessation of medication or appropriate treatment can be individualized for each patient for the purpose of preventing further damage to tissue structure and function. Being aware of these associations, physicians may readily identify medications that may cause uveitis and avoid expensive and unnecessary clinical and laboratory testing.

Predict New Therapeutic Drugs for Hepatocellular Carcinoma Based on Gene Mutation and Expression

Hepatocellular carcinoma (HCC) is the fourth most common primary liver tumor and is an important medical problem worldwide. However, the use of current therapies for HCC is no possible to be cured, and despite numerous attempts and clinical trials, there are not so many approved targeted treatments for HCC. So, it is necessary to identify additional treatment strategies to prevent the growth of HCC tumors. We are looking for a systematic drug repositioning bioinformatics method to identify new drug candidates for the treatment of HCC, which considers not only aberrant genomic information, but also the changes of transcriptional landscapes. First, we screen the collection of HCC feature genes, i.e., kernel genes, which frequently mutated in most samples of HCC based on human mutation data. Then, the gene expression data of HCC in TCGA are combined to classify the kernel genes of HCC. Finally, the therapeutic score (TS) of each drug is calculated based on the kolmogorov-smirnov statistical method. Using this strategy, we identify five drugs that associated with HCC, including three drugs that could treat HCC and two drugs that might have side-effect on HCC. In addition, we also make Connectivity Map (CMap) profiles similarity analysis and KEGG enrichment analysis on drug targets. All these findings suggest that our approach is effective for accurate predicting novel therapeutic options for HCC and easily to be extended to other tumors.

Drug-induced Uveitis in HIV Patients with Ocular Opportunistic Infections

Purpose: To describe drug-induced uveitis in immunocompromised patients diagnosed with Human Immunodeficiency Virus (HIV) infection Methods: Narrative Review Results: Systemic and intraocular medications administered for the treatment of acquired immune deficiency syndrome (AIDS)-associated diseases in patients infected with HIV are a well-known cause of uveitis. Conclusions: Cidofovir and rifabutin, among other novel anti-retroviral therapies, are strongly associated with drug-induced uveitis. It is imperative to understand the pathogenesis, clinical findings, and management of HIV patients with uveitis induced by these agents.

Drug-induced uveitis

INTRODUCTION

Drug-induced uveitis is a well described but often overlooked and/or misdiagnosed adverse reaction to medication. There are an increasing number of medications that have been related to the onset of intraocular inflammation. Identification of these inciting agents may decisively help the diagnostic algorithm involving new cases of uveitis.

AREAS COVERED

This review intends to be an updated comprehensive, practical guide for practitioners regarding the main drugs that have been associated with uveitis. A classification proposed by Naranjo et al. in 1981 for establishing potential causality is applied examining possible mechanisms of action. A guide for clinicians about the rationale of these observations when dealing with patients with uveitis is provided.

EXPERT OPINION

Several agents with different routes of administration (systemic, topical and/or intraocular) may cause intraocular inflammation. The mechanism behind ocular inflammation is frequently unknown. Clinicians should be aware of the potential drug effect to optimize diagnosis and management of such patients.

Drug-induced uveitis

A number of medications have been associated with uveitis. This review highlights both well-established and recently reported systemic, topical, intraocular, and vaccine-associated causes of drug-induced uveitis, and assigns a quantitative score to each medication based upon criteria originally described by Naranjo and associates.

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.

Review article: rifabutin in the treatment of refractory Helicobacter pylori infection

BACKGROUND

Even with the current most effective treatment regimens, a relevant proportion of patients will fail to eradicate Helicobacter pylori infection.

AIM

To evaluate the role of rifabutin in the treatment of H. pylori infection.

METHODS

Bibliographical searches were performed in MEDLINE. Data on the efficacy of rifabutin-containing regimens on H. pylori eradication were combined and meta-analysed using the generic inverse variance method.

RESULTS

Rifabutin shows good in vitro activity against H. pylori. Mean H. pylori rifabutin resistance rate (calculated from 11 studies including 2982 patients) was 1.3% (95% confidence interval = 0.9-1.7%). When only studies including patients naïve to H. pylori eradication treatment were considered, this figure was even lower (0.6%). On the other hand, higher values of rifabutin resistance were calculated (1.59%) when only post-treatment patients were considered. Overall, mean H. pylori eradication rate (intention-to-treat analysis) with rifabutin-containing regimens (1008 patients) was 73% (67-79%). Respective cure rates for second-line (223 patients), third-line (342 patients) and fourth/fifth-line (95 patients) rifabutin therapies were 79% (67-92%), 66% (55-77%) and 70% (60-79%) respectively. For treating H. pylori infection, almost all studies have administered rifabutin 300 mg/day; this dose seems to be more effective than 150 mg/day. The ideal length of treatment remains unclear, but 10- to 12-day regimens are generally recommended. The mean rate of adverse effects was 22% (19-25%). Myelotoxicity is the most significant, although this complication was rare. Until now, all patients have recovered of leucopenia uneventfully in a few days, and there have been no reports of infection or other adverse outcomes related to it.

CONCLUSION

Rifabutin-containing rescue therapy constitutes an encouraging strategy after multiple (usually three) previous eradication failures with key antibiotics such as amoxicillin, clarithromycin, metronidazole, tetracycline and levofloxacin.

Intraocular tuberculosis

Intraocular manifestations of tuberculosis (TB) are rare, but TB infection is common worldwide, especially in developing economies, and in immigrant populations and immunocompromised patients in developed nations. The current review focuses on the clinical characteristics and diagnostic modalities useful in the diagnosis of intraocular TB. Specifically, IFN-gamma Release Assays (IGRAs), antigen-detection assays, and polymerase chain reactions will be discussed. Clinical management of TB patients includes counseling and testing for HIV infection. The use of corticosteroids along with anti-tuberculous medications and special therapeutic considerations in immunocompromised patients are discussed.

Tuberculosis

PURPOSE OF REVIEW

The purpose of this report is to present an update on the manifestations and management of ocular tuberculosis.

RECENT FINDINGS

Tuberculosis affects one-third of the world's population. The incidence of tuberculosis has increased with the increase in the HIV infected population. Following a resurgence of the disease in the US, the incidence has recently declined. Patients may develop scleritis that can be focal, nodular or diffuse with or without keratitis. Anterior granulomatous uveitis may occur. The posterior segment reveals vitritis, choroiditis, and can mimic serpiginous choroiditis and other entities. Patients who are immunosuppressed or HIV infected may develop active mycobacterial disease in the eye leading to rapid destruction of the ocular structures. The diagnosis of ocular tuberculosis is made by isolation of Mycobacterium tuberculosis on Löwestein-Jensen medium or by PCR. The diagnosis is supported by the clinical findings, imaging techniques including optical coherence tomography, fluorescein angiography, indocyanine green and ultrasonography. Tuberculin skin test helps to confirm the diagnosis.

SUMMARY

Ocular tuberculosis may occur in the absence of pulmonary disease. Patients present with a spectrum of clinical signs. The disease may mimic several clinical entities. Early diagnosis and prompt treatment of ocular tuberculosis may prevent ocular morbidity and blindness.

The effectiveness of rifabutin triple therapy for patients with difficult-to-eradicate Helicobacter pylori in clinical practice

BACKGROUND

Failure of first line and subsequent Helicobacter pylori eradication therapy is a significant problem and alternative treatments are few.

AIMS

To evaluate the efficacy of a rifabutin-based triple therapy in clinical practice and determine the optimal strategy for its use.

METHODS

Patients referred after first or subsequent treatment failure were prescribed rifabutin triple therapy consisting of standard dose proton pump inhibitor, amoxicillin 1 g and rifabutin 150 mg each b.d. for 10 days.

RESULTS

In 67 patients, the main indications for treatment were dyspepsia (55%), peptic ulcer disease (24%) and increased gastric cancer risk (18%). The median number of previous treatments was 2 (range: 1-9). Eradication of Helicobacter pylori was achieved in 76% (48/63) per protocol and 72% (48/67) on an intention-to-treat basis. When used as second line therapy, 95% (18/19) achieved eradication compared with 68% (30/44) when two or more previous treatments had been used (P = 0.03). Outcome was independent of age, ethnicity, gender or indication for treatment. Adverse events were reported in 10%.

CONCLUSION

Rifabutin triple therapy is a well tolerated and effective second line therapy in the treatment of persistent Helicobacter pylori; however, its efficacy decreases with increasing number of failed previous therapies.