Aspergillus endophthalmitis. An unrecognized endemic disease in orthotopic liver transplantation

Clinical Insights: Antimicrobial Therapy for Infectious Uveitis

Infectious uveitis is a major global cause of vision impairment. Despite the eye's immune privilege, afforded by the blood-ocular barrier that restricts microbial entry, several pathogens such as bacteria, viruses, fungi, and parasites can still infiltrate and cause ocular infections and complications. Clinicians often encounter significant challenges in treating infectious uveitis due to limited or ineffective treatment options. Modern molecular techniques and imaging can aid in diagnosing and assessing intraocular infections. Various antimicrobial therapies exist, spanning topical and systemic treatments, but these are constrained by issues like drug concentration, penetration, effective duration, toxicity, and side effects. Treatment approaches also differ based on the infection's etiology. This review provides recent updates on antimicrobial therapies from a clinical perspective, covering topical, systemic, and regional treatments for infectious uveitis.

Insights into the liver-eyes connections, from epidemiological, mechanical studies to clinical translation

Maintenance of internal homeostasis is a sophisticated process, during which almost all organs get involved. Liver plays a central role in metabolism and involves in endocrine, immunity, detoxification and storage, and therefore it communicates with distant organs through such mechanisms to regulate pathophysiological processes. Dysfunctional liver is often accompanied by pathological phenotypes of distant organs, including the eyes. Many reviews have focused on crosstalk between the liver and gut, the liver and brain, the liver and heart, the liver and kidney, but with no attention paid to the liver and eyes. In this review, we summarized intimate connections between the liver and the eyes from three aspects. Epidemiologically, we suggest liver-related, potential, protective and risk factors for typical eye disease as well as eye indicators connected with liver status. For molecular mechanism aspect, we elaborate their inter-organ crosstalk from metabolism (glucose, lipid, proteins, vitamin, and mineral), detoxification (ammonia and bilirubin), and immunity (complement and inflammation regulation) aspect. In clinical application part, we emphasize the latest advances in utilizing the liver-eye axis in disease diagnosis and therapy, involving artificial intelligence-deep learning-based novel diagnostic tools for detecting liver disease and adeno-associated viral vector-based gene therapy method for curing blinding eye disease. We aim to focus on and provide novel insights into liver and eyes communications and help resolve existed clinically significant issues.

Aspergillus Endophthalmitis: Epidemiology, Pathobiology, and Current Treatments

Fungal endophthalmitis is one of the leading causes of vision loss worldwide. Post-operative and traumatic injuries are major contributing factors resulting in ocular fungal infections in healthy and, more importantly, immunocompromised individuals. Among the fungal pathogens, the Aspergillus species, Aspergillus fumigatus, continues to be more prevalent in fungal endophthalmitis patients. However, due to overlapping clinical symptoms with other endophthalmitis etiology, fungal endophthalmitis pose a challenge in its diagnosis and treatment. Hence, it is critical to understand its pathobiology to develop and deploy proper therapeutic interventions for combating Aspergillus infections. This review highlights the different modes of Aspergillus transmission and the host immune response during endophthalmitis. Additionally, we discuss recent advancements in the diagnosis of fungal endophthalmitis. Finally, we comprehensively summarize various antifungal regimens and surgical options for the treatment of Aspergillus endophthalmitis.

Antimicrobial guide to posterior segment infections

PURPOSE

This review article is meant to serve as a reference guide and to assist the treating physician in making an appropriate selection and duration of an antimicrobial agent.

METHODS

Literature review.

RESULTS

Infections of the posterior segment require prompt medical or surgical therapy to reduce the risk of permanent vision loss. While numerous options exist to treat these infections, doses and alternative therapies, especially with contraindications for first-line therapy, are often elusive. Antimicrobial agents to treat posterior segment infections can be administered via various routes, including topical, intravitreal, intravenous, and oral.

CONCLUSIONS

Although there are many excellent review articles on the management of endophthalmitis, we take the opportunity in this review to comprehensively summarize the appropriate antimicrobial regimen of both common and rare infectious etiologies of the posterior segment, using evidence from clinical trials and large case series.

ENDOGENOUS ASPERGILLUS ENDOPHTHALMITIS IN AN IMMUNOCOMPETENT PATIENT WITH A REMOTE HISTORY OF PULMONARY TUBERCULOSIS

PURPOSE

To report a case of Aspergillus fumigatus endogenous endophthalmitis in an immunocompetent patient initially diagnosed as acute retinal necrosis.

METHODS

Case report.

PATIENT

A 67-year-old woman with a remote history of treated pulmonary tuberculosis and no ocular history presented to an outside retina specialist with a sudden onset of floaters and blurred vision in one eye. Examination and fluorescein angiography at the time revealed findings suspicious for acute retinal necrosis, and the patient was started on oral valganciclovir and an intravitreal injection of ganciclovir. Despite treatment, the patient's vision and pain worsened. After evaluation at the University of Southern California Roski Eye Institute, she was diagnosed with a likely fungal endogenous endophthalmitis based on ultrasound findings and underwent emergent vitrectomy. A chest x-ray demonstrated partial collapse of the right upper lobe with hilar enlargement.

RESULTS

Aspergillus fumigatus was cultured from vitreous, blood, and bronchoalveolar lavage samples, suggesting that the patient's infection had a pulmonary origin, most likely from the right upper lobe that had healed from previous tuberculosis infection.

DISCUSSION

To the best of our knowledge, this is the first reported case of Aspergillus endogenous endophthalmitis in an immunocompetent patient secondary to pulmonary changes that occurred from previously treated tuberculosis.

Etiological agents of fungal endophthalmitis: diagnosis and management

Endophthalmitis caused by fungi is commonly diagnosed around the world in apparently healthy and immunocompromised individuals. An accurate clinical diagnosis for endophthalmitis confirmed by laboratory techniques is essential for early treatment with antifungal drugs, such as amphotericin B, imidazoles, and other antifungals. Here, we review endophthalmitis caused by fungi according to its classification into endogenous fungal endophthalmitis (EFE) and exogenous fungal endophthalmitis (EXFE). EFE is caused by endogenously acquired fungi, whereas the traumatic implantation of opportunistic fungal pathogens is the main feature of EXFE. We highlight the most important etiologies causing endophthalmitis and the steps required for a rapid diagnosis and management.

Endophthalmitis

Endophthalmitis means bacterial or fungal infection inside the eye involving the vitreous and/or aqueous humors. Most cases are exogenous and occur after eye surgery, after penetrating ocular trauma, or as an extension of corneal infection. An increasing number of cases are occurring after intravitreal injections of anti-vascular endothelial growth factor (VEGF) medications. Endophthalmitis may also be endogenous, arising from bacteraemic or fungaemic seeding of the eye. The infected eye never serves as a source of bacteraemia or fungaemia, however. The most common pathogens in endophthalmitis vary by category. Coagulase-negative staphylococci are the most common causes of post-cataract endophthalmitis, and these bacteria and viridans streptococci cause most cases of post-intravitreal anti-VEGF injection endophthalmitis, Bacillus cereus is a major cause of post-traumatic endophthalmitis, and Staphylococcus aureus and streptococci are important causes of endogenous endophthalmitis associated with endocarditis. In Taiwan and other East Asian nations, Klebsiella pneumoniae causes most cases of endogenous endophthalmitis, in association with liver abscess. Endogenous fungal endophthalmitis in hospitalized patients is usually caused by Candida species, particularly Candida albicans. Acute endophthalmitis is a medical emergency. The most important component of treatment is the intravitreal injection of antibiotics, along with vitrectomy in severe cases. Systemic antibiotics should be used in cases of endogenous endophthalmitis and exogenous fungal endophthalmitis, but their role in exogenous bacterial endophthalmitis is uncertain. Repeated intravitreal injections of antibiotics may be necessary if there is no response to the initial therapy. Many eyes that receive prompt and appropriate treatment will recover useful vision.

Bilateral simultaneous endogenous Aspergillus endophthalmitis in an immunocompetent patient

PURPOSE

To report a case of bilateral endogenous Aspergillus endophthalmitis in an immunocompetent patient.

METHODS

We report a young immunocompetent 26-year-old Indian woman who presented with bilateral simultaneous endogenous endophthalmitis and was managed with pars plana vitreous surgery in both the eyes.

RESULTS

Smear examination of the vitrectomy specimen from the left eye identified septate hyphae with acute-angle branching, which on culture showed growth of Aspergillus fumigatus. A detailed systemic evaluation failed to reveal any systemic focus or predisposing factor for fungal infection. The patient had received an intravenous dextrose infusion 2 weeks before this episode while being treated at a rural hospital for malarial infection. During follow-up, she developed bilateral rhegmatogenous retinal detachment requiring revised pars plana vitreous surgery with silicon oil tamponade.

CONCLUSION

An immunocompetent patient can present with bilateral simultaneous endogenous Aspergillus endophthalmitis after receiving an intravenous infusion of presumably contaminated dextrose solution.

Aspergillus-Endophthalmitis nach Lebertransplantation bei einem Säugling

Immunosuppressed patients and transplant patients bear an increased risk for invasive aspergillosis and Aspergillus endophthalmitis. An 8-month-old boy developed severe unilateral panuveitis after liver transplantation. Bronchopulmonary infiltrates were present, but a pulmonary Aspergillus infection was not confirmed. An enucleation was performed in order to prevent a life-threatening disseminated Aspergillus infection.

Conjunctival aspergilloma with multiple mulberry nodules: a case report

A 30-year-old healthy female presented with a 1-year history of chronic mucous discharge, tearing, and irritation in the left eye. Slit-lamp examination revealed severe papillary and follicular reaction surrounding a movable subconjunctival mass on the left upper tarsal conjunctiva. Incision and curettage were performed to establish the diagnosis. Multiple peculiar black mulberry nodules were obtained. The clumps of septate hyphae seen with periodic acid-Schiff stain were characteristic of fungus ball (aspergilloma). The patient's symptoms improved significantly after surgery without any antifungal therapy. Although rarely reported, aspergillus is a common fungus in the conjunctiva that may seed into the subconjunctiva. We present this case to remind ophthalmologists of such a rare cause of recalcitrant conjunctival inflammation in immunocompetent patients.

Histological examination of an eye with endogenous Aspergillus endophthalmitis treated with oral voriconazole: a case report

PURPOSE

To report the histological findings of an eye with severe Aspergillus endophthalmitis after oral treatment with voriconazole. METHODS. Case report.

RESULTS

Histopathological examination revealed no fungal elements in choroidal or retinal vessels. The hyphae were mainly restricted to the vitreal side of the preretinal inflammatory infiltrate. Since the treatment with voriconazole had not been completed at the time of enucleation, the clinical course with potential further limitation or regression of the lesion remains unsettled.

CONCLUSIONS

Endogenous Aspergillus endophthalmitis is a devastating condition often associated with immunodeficiency. The pathogenesis of this entity implies the primary invasion of choroidal and retinal vessels. The lack of antifungal drugs with high blood-ocular permeability results in an extremely poor visual prognosis. Our histological examination indicates promising activity and ocular penetration of the new antifungal agent voriconazole.

Retinal complications of bone marrow and solid organ transplantation

PURPOSE OF REVIEW

A review is presented of the current literature on retinal complications of bone marrow and solid organ transplantation.

RECENT FINDINGS

Retinal complications of bone marrow and solid organ transplantation include microvascular retinopathy, infection, and hemorrhagic findings. Other clinical observations include central serous chorioretinopathy, bilateral optic disc edema, and cyclosporine-related retinal toxicity. The cause of these clinical findings is likely to be multifactorial, resulting from the combined effects of cyclosporine, total body irradiation, infections, high-dose chemotherapy, and recurrent malignancies.

SUMMARY

Understanding of these clinical entities of the posterior segment is important in minimizing the potentially sight-threatening complications from bone marrow and solid organ transplantation.

Aspergillosis in lung transplantation: incidence, risk factors, and prophylactic strategies

Invasive aspergillosis remains a significant cause of morbidity and mortality in transplantation, especially lung and allogeneic bone marrow transplant recipients. The epidemiology, classic and newly recognized risk factors, and incidence of aspergillosis are reviewed. Risk factors include environmental exposures, airway colonization, profound immunosuppression, neutropenia, prior cytomegalovirus infection, and renal dysfunction. Clinical and radiographic presentations of invasive aspergillosis are discussed, including some unusual manifestations in lung transplant recipients. Early and accurate diagnosis of aspergillosis remains a challenge, and diagnostic strategies are reviewed, with an emphasis on the chest computerized tomography scan and on transbronchial or open lung biopsy. Recent advances include prophylactic and pre-emptive antifungal strategies, newer therapeutic agents, and improved risk stratification.

Endogenous mycotic endophthalmitis: variations in clinical and histopathologic changes in candidiasis compared with aspergillosis

PURPOSE

To describe clinical and/or histopathologic features that could help distinguish endogenous Candida endophthalmitis from endogenous Aspergillus intraocular inflammation and to provide histologic documentation of intraocular spread of these agents.

METHODS

Twenty-five patients who underwent enucleation, 13 with morphologic features and/or positive culture for Aspergillus and 12 with histologic evidence and/or positive culture for Candida were included in the study. Clinical information was sought from each case. Patients with AIDS were excluded. The enucleated globes were analyzed to detect location of the fungi, vascular invasion by these agents, and inflammatory response.

RESULTS

Candida endophthalmitis was noted in patients with a history of gastrointestinal surgery, hyperalimentation, or diabetes mellitus, whereas aspergillosis was present in patients who had undergone organ transplantation or cardiac surgery. Histopathologically, the vitreous was the primary focus of infection for Candida, whereas subretinal/subretinal pigment epithelium infection was noted in eyes with aspergillosis. Retinal and choroidal vessel wall invasion by fungal elements was noted in cases of aspergillosis but not in cases with candidiasis. Both infectious agents induced suppurative nongranulomatous inflammation.

CONCLUSIONS

Unlike Candida endophthalmitis, aspergillosis clinically presents with extensive areas of deep retinitis/choroiditis, and vitreous biopsy may not yield positive results. Histopathologically, it appears that Aspergillus grows preferentially along subretinal pigment epithelium and subretinal space. This intraocular infection is usually associated with a high rate of mortality caused by cerebral and cardiac complications.

Assessing risk factors for systemic fungal infections

The incidence of invasive fungal infection has increased in recent years. Most infections are caused by Candida albicans and Aspergillus spp. but the emergence of other fungal infections is changing the spectrum of disease. Immunosuppression and breakdown of anatomical barriers such as the skin are the major risk factors for fungal infections. Health care workers encounter at-risk patients in various settings, including AIDS clinics and intensive care, transplantation and oncology units. Patients with prolonged and deep neutropenia (haematological malignancy patients) are most at risk and are therefore most likely to receive prophylactic therapy. Practical measures can be taken to avoid exposing the patient to fungi (air filtration, regular hand washing, avoiding plants and flowers) and antifungal agents can be administered to prevent systemic fungal infection. Most fungal infections have non-specific symptoms; this makes recognition of the signs and symptoms of the disease important but also makes diagnosis difficult and empirical treatment necessary. Some antifungal agents have limitations but new formulations will improve therapy and play a key role in future antifungal strategies.

Remarkable case of early Aspergillus endophthalmitis

BACKGROUND

This case demonstrates the early stage of Aspergillus endophthalmitis and is the second ultrastructural study of endogenous Aspergillus endophthalmitis. It is the first description of phagocytosis of Aspergillus fungi by retinal pigment epithelium (RPE).

METHODS

A case report and detailed light- and electron microscopic findings are presented.

RESULTS

Histopathological examination of serial sections of the affected right eye displayed a spread of Aspergillus fumigatus fungi along two separate paths: via the retinal and choroidal vessels. The retinal and choroidal lesions were not contiguous. The organisms penetrated blood vessel walls, Bruch's membrane and the internal limiting membrane, but not the RPE layer. A curious accumulation of the Aspergillus fungi was present on the internal aspect of Bruch's membrane, where the RPE acted as a barrier and the subretinal space was not invaded. Phagocytosis of fungi by the RPE was observed. No inflammatory cells were present between Bruch's membrane and the RPE.

CONCLUSIONS

This report describes a remarkable barrier function, possible local immunosuppression and phagocytosis by the RPE cells in a case of early Aspergillus endophthalmitis.

Aspergillus fumigatus endophthalmitis in a patient with acute myeloid leukaemia

A 55-year-old patient developed progressive loss of vision in one eye following induction chemotherapy for acute myeloid leukaemia (AML). Aspergillus fumigatus was cultured from vitreal aspirates. The patient was treated with intravenous and intravitreal amphotericin B but suffered complete loss of vision in her right eye. We believe this is the first report of culture-proven Aspergillus fumigatus endophthalmitis in a patient treated for a haematological malignancy.

Endophthalmitis

Endophthalmitis is an inflammatory reaction of intraocular fluids or tissues. Infectious endophthalmitis is one of the most serious complications of ophthalmic surgery. Occasionally, infectious endophthalmitis is the presenting feature of an underlying systemic infection. Successful management of infectious endophthalmitis depends on timely diagnosis and institution of appropriate therapy. Recognition of the different clinical settings in which endophthalmitis occurs and awareness of the highly variable presentation it may have facilitate timely diagnosis. Biopsy of intraocular fluid/tissue is the only method that permits reliable diagnosis and treatment. The different presenting clinical settings, a rational approach to diagnosis (i.e., when, what, and how to biopsy), and the treatment of infectious endophthalmitis are reviewed.

Hospital construction-associated outbreak of ocular aspergillosis after cataract surgery

OBJECTIVE

This study aimed to report an outbreak of Aspergillus endophthalmitis after cataract extraction during hospital construction.

DESIGN

The study design is a case series of an outbreak of Aspergillus endophthalmitis.

PARTICIPANTS

Five patients in whom Aspergillus endophthalmitis developed during a period of hospital construction in Jeddah, Saudi Arabia, participated. Severe postoperative uveitis occurred in all five patients and failed to subside with topical steroid therapy. The patients were referred to the King Khaled Eye Specialist Hospital for treatment. The causative organism was identified as Aspergillus fumigatus in each case.

INTERVENTION

All five patients were subjected to aqueous or vitreous tap. Three patients had vitrectomy. Patients were given systemic, periocular, and intravitreous antifungal agents.

MAIN OUTCOME

The final outcome in each patient was evisceration or enucleation, despite an intensive course of antifungal therapy.

RESULTS

There were five patients, three females and two males, ranging in age from 51 to 65 years. Postoperative signs of infection developed in the patients 4 to 15 days after surgery. In all five cases, cultures of aqueous or vitreous grew A. fumigatus.

CONCLUSION

Aspergillus endophthalmitis is a serious and devastating complication of ocular surgery. The outbreak, herewith, may have been related to hospital construction. The infection can be prevented, notably, by proper maintenance of old, "sick" buildings and by following certain procedures during hospital construction.

Endogenous Aspergillus endophthalmitis. Clinical features and treatment outcomes

OBJECTIVE

This study evaluated the clinical features and treatment outcomes in patients with endogenous Aspergillus endophthalmitis.

DESIGN

The study design was a multicenter retrospective chart review.

PARTICIPANTS

Ten patients (12 eyes) with culture-proven endogenous Aspergillus endophthalmitis treated by 1 of the authors were studied.

INTERVENTION

Intravitreous amphotericin B injection, pars plana vitrectomy, systemic amphotericin B therapy, and oral anti-fungal therapy were performed.

MAIN OUTCOME MEASURES

Elimination of endogenous Aspergillus endophthalmitis and Snellen visual acuity, best corrected, were measured.

RESULTS

All patients had a 1- to 3-day history of pain and marked loss of visual acuity in the involved eyes. Varying degrees of vitritis was present in all 12 eyes. In 8 of 12 eyes, a central macular chorioretinal inflammatory lesion was present. Four patients (six eyes) had associated pulmonary diseases and were receiving concurrent steroid therapy. One of these patients with chronic asthma also was abusing intravenous drugs. Overall, six patients (six eyes) had a history of intravenous drug abuse, whereas a seventh patient (one eye) was suspected of abusing intravenous drugs. Blood cultures and echocardiograms were negative for systemic aspergillosis. Management consisted of a pars plana vitrectomy in 10 of 12 eyes. Intravitreous amphotericin B was administered in 11 of 12 eyes. Systemic amphotericin B therapy was used in eight patients. One patient was treated with oral antifungal agents. In three eyes without central macular involvement, final visual acuities were 20/25 to 20/200. In eight eyes with initial central macular involvement, final visual acuities were 20/400 in three eyes and 5/200 or less in four eyes. Two painful eyes with marked inflammation, hypotony, and retinal detachment were enucleated.

CONCLUSIONS

Endogenous Aspergillus endophthalmitis usually has an acute onset of intraocular inflammation and often has a characteristic chorioretinal lesion located in the macula. Although treatment with pars plana vitrectomy and intravitreous amphotericin B is capable of eliminating the ocular infection, the visual outcome generally is poor, especially when there is direct macular involvement.

Implications of early systemic therapy on the incidence of endogenous fungal endophthalmitis

OBJECTIVE

In the past, evidence of endogenous fungal endophthalmitis has been used as a guide to initiating potentially toxic antifungal therapy in patients with systemic fungal infections. Recently, however, a trend has developed to provide patients with antifungal therapy at the first evidence of fungal infection. The authors' study evaluates the incidence of endogenous fungal endophthalmitis in this setting.

DESIGN

The design is a retrospective review of the medical records of patients examined by the inpatient ophthalmology consultation service to rule out endogenous fungal endophthalmitis between January 1994 and April 1996 at the University of Michigan Hospitals, Ann Arbor, Michigan.

PARTICIPANTS

Two hundred fourteen eyes of 107 patients with a diagnosis of systemic fungal infection were studied.

INTERVENTION

A review of medical records was performed.

MAIN OUTCOME MEASURES

The findings of the ocular examination, the presence of risk factors for disseminated fungal infection, the type of antifungal therapy, and the source and identity of the isolated fungus were recorded.

RESULTS

The majority of patients examined had either fungal growth from blood cultures or evidence of deep tissue fungal infection. All patients in the study were at risk for fungal disease with each having at least one risk factor for disseminated fungal infection. Of the patients examined, 93.4% already were receiving systemic antifungal therapy at the time of ophthalmologic consultation. Only 3 (2.8%) of the 107 patients examined had chorioretinal findings consistent with early endogenous fungal endophthalmitis. None had intravitreous involvement, and the ocular findings did not change the course of therapy.

CONCLUSIONS

Early systemic treatment of deep tissue fungal infection appears to dramatically decrease the incidence of endogenous fungal endophthalmitis.

Antifungal prophylaxis during neutropenia and immunodeficiency

Fungal infections represent a major source of morbidity and mortality in patients with almost all types of immunodeficiencies. These infections may be nosocomial (aspergillosis) or community acquired (cryptococcosis), or both (candidiasis). Endemic mycoses such as histoplasmosis, coccidioidomycosis, and penicilliosis may infect many immunocompromised hosts in some geographic areas and thereby create major public health problems. With the wide availability of oral azoles, antifungal prophylactic strategies have been extensively developed. However, only a few well-designed studies involving strict criteria have been performed, mostly in patients with hematological malignancies or AIDS. In these situations, the best dose and duration of administration of the antifungal drug often remain to be determined. In high-risk neutropenic or bone marrow transplant patients, fluconazole is effective for the prevention of superficial and/or systemic candidal infections but is not always able to prolong overall survival and potentially selects less susceptible or resistant Candida spp. Primary prophylaxis against aspergillosis remains investigative. At present, no standard general recommendation for primary antifungal prophylaxis can be proposed for AIDS patients or transplant recipients. However, for persistently immunocompromised patients who previously experienced a noncandidal systemic fungal infection, prolonged suppressive antifungal therapy is often indicated to prevent a relapse. Better strategies for controlling immune deficiencies should also help to avoid some potentially life-threatening deep mycoses. When prescribing antifungal prophylaxis, physicians should be aware of the potential emergence of resistant strains, drug-drug interactions, and the cost. Well-designed, randomized, multicenter clinical trials in high-risk immunocompromised hosts are urgently needed to better define how to prevent severe invasive mycoses.