Intravitreal bevacizumab as an adjunct in a patient with presumed vascularised choroidal tubercular granuloma

The first-in-class pyrazole-based dual InhA-VEGFR inhibitors towards integrated antitubercular host-directed therapy

Several facets of the host response to tuberculosis have been tapped for clinical investigation, especially targeting angiogenesis mediated by VEGF signaling from infected macrophages. Herein, we rationalized combining the antiangiogenic effects of VEGFR-2 blockade with direct antitubercular InhA inhibition in single hybrid dual inhibitors as advantageous alternatives to the multidrug regimens. Inspired by expanded triclosans, the ether ligation of triclosan was replaced by rationalized linkers to assemble the VEGFR-2 inhibitors thematic scaffold. Accordingly, new series of 3-(p-chlorophenyl)-1-phenylpyrazole derivatives tethered to substituted ureas and their isosteres were synthesized, evaluated against Mycobacterium tuberculosis virulent cell line H37Rv, and assessed for their InhA inhibitory activities. The urea derivatives 8d and 8g exhibited the most promising antitubercular activity (MIC = 6.25 µg/mL) surpassing triclosan (MIC = 20 µg/mL) with potential InhA inhibition, thus identified as the study hits. Interestingly, both compounds inhibited VEGFR-2 at nanomolar IC50 (15.27 and 24.12 nM, respectively). Docking and molecular dynamics simulations presumed that 8d and 8g could bind to their molecular targets InhA and VEGFR-2 posing essential stable interactions shared by the reference inhibitors triclosan and sorafenib. Finally, practical LogP, Lipinski's parameters and in silico ADMET calculations highlighted their drug-likeness as novel leads in the arsenal against TB.

Adjunctive Intravitreal Anti-vascular Endothelial Growth Factor and Moxifloxacin Therapy in Management of Intraocular Tubercular Granulomas

PURPOSE

To report pre and post treatment levels of VEGF-A in the aqueous humour of patients with intraocular tubercular granulomas and study the effect of a combined intravitreal anti-VEGF bevacizumab and moxifloxacin therapy on their regression.

METHODS

Aqueous samples of 10 consecutive patients with intraocular tubercular granulomas obtained before and after initiating treatment were subjected to ELISA for analysing intraocular VEGF-A levels. Intravitreal injections of bevacizumab and moxifloxacin were given weekly till complete regression of these granulomas. All patients received the usual four-drug ATT and oral corticosteroids.

RESULTS

Mean baseline VEGF-A level was 1004.27±411.40 pg/ml (401.32-1688.95) that reduced significantly to 27.62±46.86 pg/ml (6.9-131.83) at the last injection. Meannumber of intravitreal injections was 3.1 (2-4). We found significant correlation of decreasing levels of aqueous VEGF-A with the clinical regression of these tubercular granulomas.

CONCLUSIONS

Intraocular TB granulomas have high levels of VEGF-A. Weekly intravitreal injections of anti-VEGF bevacizumab with moxifloxacin as an adjunct to the standard care may cause prompt regression of tubercular granulomas.

ABBREVIATIONS

TB: Tuberculosis; IOTB: Intraocular tuberculosis; VEGF: Vascular endothelial growth factor; RD: Retinal detachment; Mtb: Mycobacterium tuberculosis; ATT: Antitubercular therapy; AMD: Age-related macular degeneration; SRF: Subretinal fluid; ELISA: Enzyme immunosorbent assay; PCR: Polymerase chain reaction; ONH: Optic nerve head; MDR-TB: Multidrug-resistant tuberculosis; pg/ml: picogram/milliliter; ESR: Erythrocyte sedimentation rate; CECT: Contrast enhanced computed tomography; DNA: Deoxyribonucleic acid; RNA: Ribonucleic acid; BSL: Biosafety level; BCVA: Best corrected visual acuity; HM: Hand movements; KP: Keratic precipitates; PSC: Posterior subcapsular cataract; PS: Posterior synechiae; CRA: Chorio-retinal atrophy; IVMP: Intravenous methyl prednisolone; OCT: Optical coherence tomography; RPE: Retinal pigment epithelium; FFA: Fundus fluorescein angiography; ICG: Indocyanine angiography; RAP: Retinal arterial proliferans.

Photodynamic Therapy for the Treatment of Vascularized Intraretinal Tuberculoma

PURPOSE

To report a case of intraretinal tubercular granuloma successfully treated with photodynamic therapy (PDT).

METHODS

Retrospective case report. Multimodal imaging was performed at each follow-up visit.

RESULTS

The tuberculoma did not regress and did not significantly reduce its exudation after anti-tubercular therapy (ATT), systemic steroid therapy and intravitreal anti-VEGF. Second line treatment with PDT was attempted. The lesion showed a regression with reduced sub-retinal fluid and intra-retinal exudates. A second PDT was performed for reactivation of the lesion 5 months after the first treatment. Further regression of the lesion was observed.

CONCLUSION

PDT may be a valuable second-line therapeutic approach for vascularized intraretinal granulomas.

Anti-TB monotherapy for choroidal tuberculoma: an observational study

BACKGROUND

Choroidal tuberculoma is possibly the most unequivocal manifestation of ocular infection with Mycobacterium tuberculosis. Here, we investigate the need for adjunctive corticosteroids in the management of this infection. We have compared the efficacy of anti-tubercular therapy (ATT) with or without oral corticosteroids, in management of choroidal tuberculoma.

METHODS

We report a retrospective, observational study of patients treated with ATT for choroidal tuberculoma. Group A patients were treated with standard 6-month ATT alone, and Group B with ATT and oral corticosteroids, with/without intravitreal triamcinolone/ bevacizumab injections. Primary outcome measure was time to complete resolution of lesions. Secondary measures were time to first sign of resolution and change in best corrected visual acuity (BCVA) at final visit.

RESULTS

Fourteen patients were included in the study-seven in Group A and seven in Group B. Both groups had similar duration of symptoms and size of lesions but not baseline BCVA (p = 0.02). Perilesional fluid was noted in all eyes in each group. Mean time to complete resolution in group A was 1.89 ± 0.28 (range 1.25-2) months, significantly lesser than group B (5.17 ± 2.64 [range 2-9] months, p = 0.005, Mann-Whitney test). Mean time to first sign of resolution (range from 5 days to 10 weeks, p = 0.35) and mean change in BCVA between presentation and final follow up (p = 0.2) were comparable between both groups.

CONCLUSION

Anti-TB monotherapy alone, may be sufficient for resolution of at least, select cases of choroidal tuberculoma, without the need for adjunctive corticosteroids.

Clinical features and long-term treatment outcomes in choroidal tuberculoma

PURPOSE

To investigate the clinical features and treatment outcomes of patients with choroidal tuberculoma.

METHODS

In this retrospective, observational case series, the medical records of five patients with choroidal tuberculoma who were followed up at a university hospital for at least 6 months were analyzed.

RESULTS

Of five patients, one was male and four were female. The overall mean age was 38.0 ± 9.4 years (mean follow-up: 41.2 ± 33.8 months). Tuberculin skin test was performed in three patients, and it was positive in two of them. Interferon-gamma assay was performed in two patients and was positive in all two. Three patients had systemic tuberculosis involving the lung or other organs. Five patients were treated with antitubercular therapy for a period of 9.6 ± 8.6 months. Systemic corticosteroid treatment was performed in 3 patients, with a period of 3.5 ± 0.7 months. One patient with a recurrent vascularized tuberculoma was successfully treated with single intravitreal bevacizumab injection.

CONCLUSION

Choroidal tuberculoma can develop without evidence of systemic tuberculosis and can recur despite antitubercular treatment. High index of suspicion is important in early detection, and management of choroidal tuberculoma. In cases of suspected choroidal tuberculoma, positive results on immunological tests would be sufficient to initiate antitubercular therapy even if radiological evidence of systemic tuberculosis is not found. Antitubercular therapy combined with systemic corticosteroids provided favorable results. Intravitreal injection of anti-vascular endothelial growth factor may be considered for highly vascularized choroidal tuberculoma.

Clinical and Multimodal Imaging Clues in Differentiating Between Tuberculomas and Sarcoid Choroidal Granulomas

PURPOSE

To compare the differences among clinical, demographic, and multimodal imaging features of choroidal granulomas associated with tuberculosis and sarcoidosis.

DESIGN

Retrospective comparative case series.

METHODS

Clinical features and fundus imaging, including fluorescein and indocyanine green angiography and optical coherence tomography of patients with tuberculomas and sarcoid choroidal granulomas seen at 3 tertiary care centers, were reviewed. The differences among clinical appearances, including morphology of the lesions (size, shape, extent), vascularity, and multimodal imaging features, were compared. Repeated logistic regression measurements with a multilevel random effects model was used to assess characteristics of individual granulomas that could predict the underlying cause.

RESULTS

The study included 47 eyes of 38 patients (22 with tuberculomas and 16 with sarcoid granulomas; total of 138 granulomas). Patients with tuberculomas were significantly younger (33.8 ± 10.1 vs. 48.6 ± 14.3 years, respectively; P = .002), but no sex differences were observed. In comparison with sarcoid granulomas, tuberculomas were solitary (P <.001), intense yellow, lobulated, full thickness, and located in the perivascular region (all P <.001); they were also larger (16.01 ± 9.7 mm² vs. 2.7 ± 4.5 mm², respectively; P <.001) and were vascularized (P <.001). Sarcoid granulomas were associated with retinal vasculitis (P = .003) and disc hyperfluorescence (P <.001). Logistic regression showed that multiple granulomas were associated with sarcoidosis (odds ratio [OR]: 3.5; 95% confidence interval: 1.8-6.9; P <.001). Granulomas larger than 6.45 mm² had the highest area under the receiver operating curves (0.94) for differentiating tuberculomas from sarcoid granulomas.

CONCLUSIONS

Tuberculomas and sarcoid choroidal granulomas have various clinical and imaging features that help differentiate between the 2 entities with high predictability and can supplement immunological and radiological tests in a diagnosis.

Recent Advances in Diagnosis and Treatment of Infectious Uveitis Prevalent in Asia-Pacific Region

ABSTRACT

The role of infections in intraocular inflammation is being increasingly recognized across the world. The Asia-Pacific region, being the single largest and most populous geographical entity on the planet, is home to a wide variety of such infections. Not surprisingly, there has been an explosion in the literature on infectious uveitis emerging from Asia-Pacific countries. In this review, we have covered recent advances in the diagnosis, treatment, and pathogenesis of common forms of infectious uveitis from the Asia-Pacific region. Much of the literature is focussed on the diagnosis of these infections by clinical criteria and laboratory investigations. There has also been an increased emphasis on the application of newer modes of ocular imaging and understanding pathomechanisms of ocular inflammation in these infections. Together this research has significantly improved our understanding of the diagnosis and management of infectious uveitis.

Correlation of vascular endothelial growth factor with the clinical regression of tubercular granuloma

Tubercular granulomas are a common manifestation of intraocular tuberculosis. These are said to be hypoxic granulomas with increased expression of vascular endothelial growth factor (VEGF). Management of these granulomas includes a combination of antitubercular therapy (ATT) and oral corticosteroids. We report a case of tubercular granuloma with exudative retinal detachment which was treated with weekly intravitreal anti-VEGF and antibiotic injections along with ATT and corticosteroids. The VEGF levels measured paralleled with the clinical regression of the granuloma.

Host-directed therapies targeting the tuberculosis granuloma stroma

Mycobacteria have co-evolved with their hosts resulting in pathogens adept at intracellular survival. Pathogenic mycobacteria actively manipulate infected macrophages to drive granuloma formation while subverting host cell processes to create a permissive niche. Granuloma residency confers phenotypic antimicrobial resistance by physically excluding or neutralising antibiotics. Host-directed therapies (HDTs) combat infection by restoring protective immunity and reducing immunopathology independent of pathogen antimicrobial resistance status. This review covers innovative research that has discovered ‘secondary’ symptoms of infection in the granuloma stroma are actually primary drivers of infection and that relieving these stromal pathologies with HDTs benefits the host. Advances in our understanding of the relationship between tuberculosis and the host vasculature, haemostatic system and extracellular matrix reorganisation are discussed. Preclinical and clinical use of HDTs against these stromal targets are summarised.

Revisiting hypoxia therapies for tuberculosis

The spectre of the coming post-antibiotic age demands novel therapies for infectious diseases. Tuberculosis (TB), caused by Mycobacterium tuberculosis, is the single deadliest infection throughout human history. M. tuberculosis has acquired antibiotic resistance at an alarming rate with some strains reported as being totally drug resistant. Host-directed therapies (HDTs) attempt to overcome the evolution of antibiotic resistance by targeting relatively immutable host processes. Here, I hypothesise the induction of hypoxia via anti-angiogenic therapy will be an efficacious HDT against TB. I argue that anti-angiogenic therapy is a modernisation of industrial revolution era sanatoria treatment for TB, and present a view of the TB granuloma as a 'bacterial tumour' that can be treated with anti-angiogenic therapies to reduce bacterial burden and spare host immunopathology. I suggest two complementary modes of action, induction of bacterial dormancy and activation of host hypoxia-induced factor (HIF)-mediated immunity, and define the experimental tools necessary to test this hypothesis.

Optical Coherence Tomography and Management of a Retinal Granuloma in Presumed Ocular Sarcoidosis

Purpose: To highlight the utility of EDI-OCT and periocular steroid administration for the treatment of a retinal granuloma due to presumed ocular sarcoidosis. Methods: Retrospective case-study of a single patient. Results: A 45-year-old African-American male with blurred vision in the right eye was found to have a macula-involving retinal granuloma. Laboratory, imaging, and clinical findings were consistent with a diagnosis of presumed ocular sarcoidosis. Optical coherence tomography (OCT) and fundus photographs were used to document granuloma evolution. Oral prednisone 60mg was initiated and tapered to 10mg within 2 months. Due to systemic side-effects and inadequate treatment response with prednisone, 5 sub-Tenon's triamcinolone acetonide (PSTA) injections were then administered over 7 months, and oral prednisone was discontinued at 6 months. Conclusion: This case demonstrated marked granuloma regression occurring with improvement in visual acuity, highlighting the utility of OCT and PSTA in managing retinal sarcoid granulomas.

Tuberculous Uveitis Presenting with a Bullous Exudative Retinal Detachment: A Case Report and Systematic Literature Review

Purpose: To describe tuberculous uveitis (TU) presenting as a bullous retinal detachment (RD) and to perform a comprehensive literature review on TU with similar features. Methods: Observational case report and systematic literature review. Results: An 84-year-old woman presented with bilateral granulomatous uveitis and bullous RD in the left eye. The interferon gamma release assay was strongly positive, but all other tests were unremarkable. The patient was diagnosed with TU and started on anti-tubercular therapy (ATT) and systemic steroids with excellent treatment response. Twenty-six articles (32 cases) reported TU with exudative RD. Choroidal tuberculoma was the most common clinical manifestation, followed by optic disc edema and retinal exudate. Systemic steroids with ATT improved vision in more patients (78.6%) than ATT alone (50.0%) or oral steroids followed by ATT (50.0%). Conclusion: Atypical presentations of TU make diagnosis and treatment difficult. A high level of suspicion for TU is needed to minimize ocular morbidity.

Bevacizumab for paradoxical worsening treatment adjunct in HIV patient with choroidal tuberculoma

The use of anti-tubercular therapy (ATT) along with anti-retroviral therapy (ART) in human immunodeficiency virus-tuberculosis (HIV-TB) co-infected individuals could at times lead to paradoxical worsening due to an increase in the inflammatory activity due to immune reconstitution inflammatory syndrome (IRIS) in the eye. This is characterized by anterior and posterior segment inflammatory reactions which may occur in the form of serous retinal detachment. We describe a case where the use of intravitreal anti-vascular endothelial growth factor (anti-VEGF) agent led to resolution of the serous retinal detachment, which had failed to respond to other common modalities of treatment.

An HIV-TB co-infected 18-year-old, male patient, who was started on ART and ATT developed IRIS in the form of worsening of serous retinal detachment around a pre-existent asymptomatic tuberculoma. The patient was initially treated with oral and topical steroids without a satisfactory response. Intravitreal bevacizumab was then tried for this patient. Serial fundus photos and optical coherence tomography (OCT) taken before and after treatment showed complete resolution of the serous retinal detachment with two doses of intravitreal bevacizumab.

Intravitreal anti-VEGF agents may have a role in the reversal of serous retinal detachment, which occurs as a part of IRIS in HIV-tuberculosis co-infected individuals who have been started on anti-tubercular and anti-retroviral therapies.

Optic Nerve Head Tubercular Granuloma Successfully Treated with Anti-VEGF Intravitreal Injections in Addition to Systemic Therapy

Purpose

To describe a case of optic nerve head tubercular granuloma, unresponsive to conventional therapy (antitubercular drugs and systemic steroids), successfully treated with anti–vascular endothelial growth factor (VEGF) intravitreal injections in addition to systemic drugs.

Methods

Case report.

Results

A 44-year-old patient was referred to our clinic for progressive vision decrease in his left eye during the preceding 4 months. A large granuloma infiltrating optic nerve head was visible at funduscopic examination along with diffuse intraocular inflammation. Workup for granulomatous uveitis supported the diagnosis of presumed intraocular tuberculosis. However, the large granulomatous lesion did not show a good response to conventional therapy for tubercular uveitis (antitubercular drugs and systemic steroids). Anti-VEGF (bevacizumab) intravitreal injections were performed as an adjunct to the ongoing therapy. After 2 injections, the patient showed an almost complete regression of the lesion (demonstrated by optical coherence tomography) and a restoration of vision.

Conclusions

Anti-VEGF intravitreal injections should be considered in the treatment of large tubercular granulomatous lesions in addition to conventional systemic therapy. Optical coherence tomography could be a suitable tool for studying and following optic nerve head granulomas.