Voriconazole-Induced Periostitis: A Mimicker of Skeletal Coccidioidomycosis.

BACKGROUND Coccidioidomycosis is caused by the fungi Coccidioides immitis and Coccidioides posadasii, which are endemic to the southwestern United States and other countries of the Western Hemisphere. Pulmonary coccidioidomycosis is the most common form of coccidioidomycosis. Rarely, coccidioidal infection disseminates to meninges, bones, skin, and soft tissues. While fluconazole remains the first line of treatment and is used for most patients, voriconazole is used in selected refractory cases of coccidioidomycosis. Voriconazole has more fluorine molecules than other azoles, and over time the fluorine molecules in voriconazole can cause disorganized bone formation in the periosteal region (periostitis), causing generalized bony pain, and radiographically can mimic skeletal coccidioidomycosis. While voriconazole-induced periostitis has been noted in aspergillosis and other infections, it has not been reported commonly in patients with coccidioidomycosis. CASE REPORT We present a case of a 50-year-old female patient with a diagnosis coccidioidal meningitis who was refractory to fluconazole and was treated with voriconazole. She presented with bony pain, which was initially radiographically attributed to multifocal skeletal coccidioidal infection. Reflecting upon the patient's history and serum levels of fluoride and bone alkaline phosphatase, a diagnosis of voriconazole-induced periostitis was made. Discontinuation of the voriconazole resulted in resolution of the periostitis. CONCLUSIONS Voriconazole-induced periostitis should be considered in patients with musculoskeletal pain with a history of voriconazole treatment or with laboratory abnormalities, such as elevated fluoride levels and/or bone alkaline phosphatase. Discontinuation of voriconazole reverses the condition promptly.

A mouldable fibreglass backslab device as a novel approach to offload chronic plantar foot ulcers: A retrospective observational audit.

BACKGROUND: Pressure offloading is a critical component of plantar foot ulcer management, including diabetes-related foot ulcers (DFU). Conventional offloading options such as total contact casting and removable knee-high walkers may be unsuitable or unsuccessful in patients with morbid obesity, intermittent lower limb oedema, high exudative wounds or poor mobility. A mouldable fibreglass backslab device (BSD) may be a practical alternative to be considered in these situations. METHODS: Data were retrospectively collected on 28 patients (29 foot ulcers) with non-healing ulcers who received a BSD to offload their foot ulcer as an extension to standard offloading care. Baseline data included: patient demographics, type of offloading prior to BSD application, date of ulcer onset, days ulcer present prior to BSD application and ulcer size at BSD initiation. Measures of success included ulcer size reduction 12 weeks post-BSD application, time to complete ulcer healing in BSD, time to 50% reduction in ulcer size post-BSD application and total number of days ulcer present. RESULTS: The median (IQR) ulcer area and ulcer duration at baseline for 19 patients (20 ulcers) who used the BSD was 1.65 (0.4-3.8) cm2 and 531 (101-635) days. At 12 weeks, the median (IQR) ulcer area was 0.3 (0-0.55) cm2 with a median (IQR) reduction of 97 (80-100) %. Nine (45%) ulcers achieved complete wound healing (100% reduction in wound size) at 12 weeks post-BSD application, and the remaining 11 (55%) ulcers achieved at least 50% reduction in wound size. The median (IQR) time to complete wound healing and 50% reduction in wound size was 71 (35-134) days and 24 (15-44) days, respectively. Nine patients ceased use of the BSD and reverted to conventional offloading before their wounds had healed. Of these, four patients achieved a 50% reduction in wound size at the 12-week mark with conventional offloading. CONCLUSION: Our preliminary data suggests that a mouldable fibreglass BSD may be a practical offloading option in the management of DFUs, especially when conventional offloading methods are unsuccessful, unsuitable or unacceptable to patients. Higher level evidence is required to demonstrate suitability or efficacy of the BSD compared to current evidence-based recommended offloading methods.

Sudden vision loss heralding COVID-19-associated aspergillosis. Report of 2 cases.

Purpose: To describe clinical, radiographic, laboratory and cytopathologic findings in 2 patients who developed vision loss due to endogenous aspergillus endophthalmitis during hospitalization for COVID-19 pneumonia. Observations: Two unvaccinated sexagenarian male smokers lost vision within one month of contracting COVID-19 pneumonia. Initially, both received high dose steroids, nasal cannula oxygen and remdesivir. Immunomodulators tocilizumab or baricitinib were added during week 2 in case 1 and 2 respectively. Upon presentation after discharge from a post-COVID rehabilitation unit, visual acuities were light perception and hand motion. In both cases, inpatient blood and ocular fluid cultures were negative, serum 1,3-beta-D-glucan was positive, and vitreous cytopathology revealed filamentous fungi and PCR was positive for Aspergillus fumigatus. Large solitary intravitreal fungus balls were debulked in patient 1 and excised in patient 2. Final visual acuities were no light perception and 20/200 respectively. MRI revealed previously unsuspected brain and lung lesions consistent with disseminated aspergillosis in patient 2. Conclusions: Vision loss due to fungal endophthalmitis may be the first or only sign of systemic aspergillosis associated with COVID-19 pneumonia. Aspergillosis should be suspected in patients who develop vision loss. Diagnosis limited by negative fungal cultures may be confirmed by vitreous cytopathology and PCR. Systemic imaging for disseminated aspergillosis is indicated. Ultimate visual acuity may depend upon surgical approach.

Serologic Rebound after Stopping Azoles for Primary Pulmonary Coccidioidomycosis: A Case-Controlled Observational Study.

BACKGROUND: We sought to characterize the outcomes of patients with primary pulmonary coccidioidomycosis whose post-treatment complement fixation (CF) titer increased by more than 2 dilutions (serologic rebound) after discontinuation of antifungal treatment. METHODS: We conducted a retrospective chart review of patients with primary pulmonary coccidioidomycosis and identified immunocompetent, non-pregnant adults who received antifungal treatment and then experienced a serologic rebound after treatment discontinuation. We compared these to matched controls similarly treated who did not have serologic rebound. RESULTS: Fifty-eight patients experienced serologic rebound. Thirty (52%) of these were associated with symptoms. Nine were associated with radiographic progression. The median time to serologic rebound was 3.5 months. Antifungal treatment was reinitiated in 37 (63.7%) patients. Four of the 58 (6.9%) with rebounded serology subsequently developed extra-thoracic dissemination. Compared with matched controls, patients with rebounded serology were more likely to have post-treatment symptoms, reinitiation of antifungal therapy, and a longer duration of clinical follow-up. However, they were not more likely to experience extra-thoracic dissemination. CONCLUSION: Serological rebound, manifested in at least 2-dilution rise of CF titer following antifungal treatment of primary pulmonary coccidioidomycosis, was uncommon, but resulted in longer clinical follow-up. Continued monitoring of such patients is important to identify the patients who develop subsequent symptoms, as well as extra-thoracic dissemination.

Nitric Oxide and its Derivatives Containing Nasal Spray and Inhalation Therapy for the Treatment of COVID-19.

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has become a major health concern worldwide and has evolved into different variants. SARS-CoV-2 possesses a spike glycoprotein on its envelope that binds to the angiotensin-converting enzyme 2 (ACE-2) receptor of the host cell via the receptor-binding domain (RBD) in the upper respiratory tract. Since the SARS-CoV-2 virus variants change the severity of the diesease and treatment scenarios, repurposing current medicines may provide a quick and appealing method with established safety features. The efficacy and safety of antiviral medicines against the coronavirus disease 2019 (COVID-19) have been investigated, and several of them are now undergoing clinical studies. Recently, it has been found that nitric oxide (NO) shows antiviral properties against SARS-CoV-2 and prevents the virus from binding to a host cell. In addition, NO is a well-known vasodilator and acts as an important coagulation mediator. With the fast-track development of COVID-19 treatments and vaccines, one avenue of research aimed at improving therapeutics is exploring different forms of drug delivery, including intranasal sprays and inhalation therapy. The nasal mucosa is more prone to be the site of infection as it is in more direct contact with the physical environment via air during inhalation and exhalation. Thus, the use of exogenous nasal NO therapy via the intranasal route displays a distinct advantage. Therefore, the objective of this review is to summarize the relevant actions of NO via the intranasal spray and inhalation delivery, its mechanism of action, and its use in the treatment of COVID-19.

Management of diabetes-related foot disease in the outpatient setting during the COVID-19 pandemic.

The use of telephone and/or video consultation in routine management of acute diabetes-related foot disease (DFD) before the coronavirus disease 2019 (COVID-19) pandemic at a tertiary hospital is unprecedented. In March 2020, the Diabetes Feet Australia (DFA) released a national guideline to inform DFD management during the COVID-19 pandemic. The present study aimed to describe the adherence to the DFA guideline of managing acute DFD using telephone and/or video consultation at a Western Australian tertiary hospital during this period. We found >80% adherence rate to the DFA guideline and the management of active DFD using telephone and/or video consultations was feasible and acceptable in carefully selected patients.

Adipose-specific ATGL ablation reduces burn injury-induced metabolic derangements in mice.

Hypermetabolism following severe burn injuries is associated with adipocyte dysfunction, elevated beige adipocyte formation, and increased energy expenditure. The resulting catabolism of adipose leads to detrimental sequelae such as fatty liver, increased risk of infections, sepsis, and even death. While the phenomenon of pathological white adipose tissue (WAT) browning is well-documented in cachexia and burn models, the molecular mechanisms are essentially unknown. Here, we report that adipose triglyceride lipase (ATGL) plays a central role in burn-induced WAT dysfunction and systemic outcomes. Targeting adipose-specific ATGL in a murine (AKO) model resulted in diminished browning, decreased circulating fatty acids, and mitigation of burn-induced hepatomegaly. To assess the clinical applicability of targeting ATGL, we demonstrate that the selective ATGL inhibitor atglistatin mimics the AKO results, suggesting a path forward for improving patient outcomes.

Sex disparities in cardiovascular disease outcomes among geriatric patients with prediabetes.

AIMS: To analyze the sex-based differences in the prevalence of cardiovascular disease risk factors and outcomes in older patients with prediabetes using demographically matched national cohorts of hospitalized patients aged ≥65 years. METHODS: We queried the 2007-2014 National Inpatient Database to identify older patients (>65 years) admitted with prediabetes using ICD-9 Clinical Modification codes. The older patients were then subcategorized based on sex. Comparative analyses of their baseline characteristics, the prevalence of cardiovascular(CV) disease comorbidities, hospitalization outcomes, and mortality rates were performed on propensity-matched cohorts for demographics. RESULTS: A total of 1,197,978 older patients with prediabetes (599,223 males; mean age 75years and 598,755 females; mean age 76years) were identified. Higher admission rates were found commonly among older white males (84.1%) and females (81.7%). Prediabetic older males showed a higher frequency of cardiovascular comorbidities compared to females. Prediabetic older males had higher all-cause in-hospital mortality (4.2% vs. 3.6%, p < 0.001), acute myocardial infarction (7.0% vs. 4.7%, p < 0.001), arrhythmia (36.3% vs. 30.5%, p < 0.001), stroke (4.8% vs. 4.6%, p < 0.001), venous thromboembolism (3.3% vs. 3.0%, p < 0.001) and percutaneous coronary intervention (3.1% vs. 1.5%, p < 0.001) compared to females. CONCLUSIONS: Our analysis revealed that among older patients hospitalized with prediabetes, males suffered worse in-hospital CV outcomes and survival rates compared to females.

Ripasudil in a Model of Pigmentary Glaucoma.

Purpose: To investigate the effects of Ripasudil (K-115), a Rho-kinase inhibitor, in a porcine model of pigmentary glaucoma. Methods: In vitro trabecular meshwork (TM) cells and ex vivo perfused eyes were subjected to pigment dispersion followed by K-115 treatment (PK115). PK115 was compared to controls (C) and pigment (P). Cytoskeletal alterations were assessed by F-actin labeling. TM cell phagocytosis of fluorescent targets was evaluated by flow cytometry. Cell migration was studied with a wound-healing assay. Intraocular pressure was continuously monitored and compared to after the establishment of the pigmentary glaucoma model and after treatment with K-115. Results: The percentage of cells with stress fibers increased in response to pigment but declined sharply after treatment with K-115 (P: 32.8% ± 2.9%; PK115: 11.6% ± 3.3%, P < 0.001). Phagocytosis first declined but recovered after K-115 (P: 25.7% ± 2.1%, PK115: 33.4% ± 0.8%, P <0.01). Migration recuperated at 12 hours with K-115 treatment (P: 19.1 ± 4.6 cells/high-power field, PK115: 42.5 ± 1.6 cells/high-power field, P < 0.001). Ex vivo, eyes became hypertensive from pigment dispersion but were normotensive after treatment with K-115 (P: 20.3 ± 1.2 mm Hg, PK115: 8.9 ± 1.7 mm Hg; P < 0.005). Conclusions: In vitro, K-115 reduced TM stress fibers, restored phagocytosis, and restored migration of TM cells. Ex vivo, K-115 normalized intraocular pressure. Translational Relevance: This ex vivo pigmentary glaucoma model provides a readily available basis to investigate new drugs such as the rho-kinase inhibitor studied here.

Clinical characteristics and in hospital outcomes of heart transplant recipients undergoing percutaneous coronary intervention: Insights from the National Inpatient Sample.

OBJECTIVES: Cardiac transplant patients are at increased risk of Coronary Allograft Vasculopathy which requires percutaneous coronary intervention (PCI). BACKGROUND: We aim to determine national epidemiology describing trends, mortality, and morbidity risks in patients with heart transplant undergoing PCI. METHODS: We used Nationwide Inpatient Sample (NIS) data from 2002 to 2014 to identify adult hospitalizations with PCI using ICD 9 codes. Acute myocardial infarction (AMI), cardiac transplant status and complications were identified using validated ICD-9-CM diagnosis codes. Endpoints were in-hospital mortality and peri-procedural complications. Propensity match analysis was performed to compare the end-points between DES and BMS. RESULTS: Total 8,613,900 patients underwent PCI, of which 1,531(0.002%) patients had prior heart transplant status. Among these 1,531 PCIs, 311(20%) were due to AMI including 125(8%) due to STEMI. 74% of PCIs were done in males and 78% of the PCIs were performed in the 60-79 age group. Out of 1,380 stents placed, 1,090 were DES (79%) and 290 (21%) were BMS. Mortality was higher in the BMS versus DES (8.34% vs. 3.45%, p = .012), CONCLUSION: We concluded that majority of the population who underwent PCI were older males. DES was used more than BMS. The use of BMS is associated with increased mortality, cardiac complications and Acute Kidney Injury requiring dialysis compared with DES which likely is representative of preferential use of DES in these patient population.

Rate and Modifiable Predictors of 30-Day Readmission in Patients with Acute Respiratory Distress Syndrome in the United States.

Background The 30-day readmission rates are being used as a quality measure by Centers for Medicare and Medicaid Services (CMS) for specific medical and surgical conditions. Acute respiratory distress syndrome (ARDS) is one of the important causes of morbidity and mortality in the United States (US). The characteristics and predictors of 30-day readmission in ARDS patients in the US are not widely known, which we have depicted in our study. Objective The aim of this study is to identify 30-day readmission rates, characteristics, and predictors of ARDS patients using the largest publicly available nationwide database. Methods We used the National Readmission Database from the year 2013 to extract the patients with ARDS by primary discharge diagnosis with ICD9-CM codes. All-cause unplanned 30-day readmission rates were calculated for patients admitted between January and November 2013. The independent predictors for unplanned 30-day readmission were identified by survey logistic regression. Results After excluding elective readmission, the all-cause unplanned 30-day readmission rate for ARDS patients was 18%. Index admissions readmitted within 30-day had a significantly higher baseline burden of comorbidities with a Charlson Comorbidity Index (CCI) ≥1 as compared to those who were not readmitted within 30 days. In multivariate regression analysis, several predictors associated with 30-day readmission were self-pay/no charge/other (OR 1.19, 95%CI: 1.02-1.38; p = 0.02), higher-income class (OR 0.86, 95%CI:0.79-0.99; p = 0.03), private insurance (OR 0.81, 95%CI:0.67-0.94; p = 0.01), and teaching metropolitan hospital (OR 0.72, 95%CI:0.61-0.94; p = 0.01). Conclusion The unplanned 30-day readmission rates are higher in ARDS patients in the US. Several modifiable factors such as insurance, socioeconomic status, and hospital type are associated with 30-day readmission among ARDS patients.

Trends and outcomes of peptic ulcer disease in patients with cirrhosis.

BACKGROUND: Peptic ulcer disease (PUD) is more prevalent in cirrhotic patients and it has been associated with poor outcomes. However, there are no population-based studies from the United States (U.S.) that have investigated this association. Our study aims to estimate the incidence trends, predictors, and outcomes PUD patients with underlying cirrhosis. METHODS: We analyzed Nationwide Inpatient Sample (NIS) and Healthcare Cost and Utilization Project (HCUP) data for years 2002-2014. Adult hospitalizations due to PUD were identified by previously validated ICD-9-CM codes as the primary diagnosis. Cirrhosis was also identified with presence of ICD-9-CM codes in secondary diagnosis fields. We analyzed trends and predictors of PUD in cirrhotic patients and utilized multivariate regression models to estimate the impact of cirrhosis on PUD outcomes. RESULTS: Between the years 2002-2014, there were 1,433,270 adult hospitalizations with a primary diagnosis of PUD, out of which 70,007 (4.88%) had cirrhosis as a concurrent diagnosis. There was a significant increase in the proportion of hospitalizations with a concurrent diagnosis of cirrhosis, from 3.9% in 2002 to 6.6% in 2014 (p < 0.001). In an adjusted multivariable analysis, in-hospital mortality was significantly higher in hospitalizations of PUD with cirrhosis (odd ratio [OR] 1.78; 95% confidence interval [CI] 1.63-1.97; P < 0.001), however, there was no difference in the discharge to facility (OR 1.00; 95%CI 0.94 - 1.07; P = 0.81). Moreover, length of stay (LOS) was also higher (6 days vs. 4 days, P < 0.001) among PUD with cirrhosis. Increasing age and comorbidities were associated with higher odds of in-hospital mortality among PUD patients with cirrhosis. CONCLUSION: Our study shows that there is an increased hospital burden as well as poor outcomes in terms of higher in-hospital mortality among hospitalized PUD patients with cirrhosis. Further studies are warranted for better risk stratification and improvement of outcomes.

Outcomes of percutaneous coronary interventions in patients with liver transplant.

OBJECTIVE: Our aim is to describe characteristics of liver transplant patients undergoing percutaneous coronary interventions (PCI) as well as in-hospital outcomes including the mortality and peri-procedural complications from the largest publicly available inpatient database in the United States from 2002 to 2014. BACKGROUND: Outcomes of PCI are well studied in patients with end-stage liver disease but not well studied in patients who receive liver transplant (LT). METHODS: Data derived from Nationwide Inpatient Sample (NIS) were analyzed for years 2002-2014. Adult Hospitalizations with PCI were identified using ICD-9-CM procedure codes. LT status and various complications were identified by using previously validated ICD-9-CM diagnosis codes. Endpoints were in-hospital mortality and peri-procedural complications. Propensity match analysis was performed to compare the endpoints between two groups. RESULTS: During the study period, 8,595,836 patients underwent PCI; 4,080 (0.04%) patients had prior LT status. 93% of patients were above age 59 years, 79% were males and 69% were nonwhites. Out of the total patients with LT status, 73% had hypertension, 57% had diabetes mellitus, and 47% had renal failure. Post-PCI complications were studied further in both liver and non-LT patients after 1:1 propensity match which showed the incidence of acute kidney injury (AKI) was higher in LT group (12.3 vs 10.7%, p = .024) but dialysis requiring AKI was similar. CONCLUSION: Among the LT recipients undergoing PCI, majority were nonwhite males. Almost more than half of the recipients had diabetes mellitus and renal failure. Incidence of AKI was higher in LT group, but other peri-procedural complications were comparable.

Intraocular pressure reduction in a pigmentary glaucoma model by Goniotome Ab interno trabeculectomy.

PURPOSE: To investigate whether microsurgical excision of trabecular meshwork (TM) in an ex vivo pigmentary glaucoma model can normalize the hypertensive phenotype. METHODS: Eight eyes of a porcine pigmentary glaucoma model underwent 90° of microsurgical TM excision with an aspirating dual-blade (Goniotome (G)). 24 hours later, additional 90° of TM were removed. Anterior segments with sham surgeries served as the control (C). Outflow facility and intraocular pressure (IOP) were analyzed. Histology with hematoxylin and eosin (H&E) was obtained. RESULTS: After the first 90° TM excision, IOP was significantly lower in G (10.2±2.4 mmHg, n = 7) than C (20.0±2.0mmHg, n = 8, P<0.01). Outflow facility in G (0.38±0.07 µl/min/mmHg) was higher than C (0.16±0.02 µl/min/mmHg, P<0.01). After the second 90° TM excision, IOP in G (6.46±0.81 mmHg, n = 7) was significantly lower than C (20.3±1.7 mmHg, n = 8, P<0.001), while the outflow facility in G (0.50±0.05 µl/min/mmHg, n = 7) was higher than C (0.16±0.01 µl/min/mmHg, n = 8, P<0.001). Compared to the first excision, excision of an additional 90° did not change of IOP (P = 0.20) or outflow facility (P = 0.17) further. CONCLUSIONS: Excision of 90° of TM in a pigmentary glaucoma model using an aspirating dual-blade decreased IOP and increased outflow facility.

Two-year data comparison of ab interno trabeculectomy and trabecular bypass stenting using exact matching.

PURPOSE: To create a balanced comparison of ab interno trabeculectomy (AIT) (Trabectome) and trabecular bypass stenting (TBS) (iStent). SETTING: Eye and Ear Institute, Pittsburgh, Pennsylvania, Ross Eye Institute, Buffalo, New York, and Glaucoma Associates of Texas, Dallas, USA. DESIGN: Retrospective case series. METHODS: The primary outcome measure was an unmedicated intraocular pressure (IOP) of 21 mm Hg or less and the secondary measure was an unmedicated IOP reduction of 20% or more at 2 years. Patients were matched by baseline IOP, number of glaucoma medications, and glaucoma type using exact matching and by age using nearest neighbor matching. Individuals without a close match were excluded. All surgeries were combined with phacoemulsification. RESULTS: One hundred fifty-four AIT eyes and 110 TBS eyes were analyzed. Forty-eight AIT patients were exactly matched with 48 TBS patients. Both groups had a mean baseline IOP of 15.3 mm Hg ± 3.1 (SD). At 24 months, the mean IOP was 13.9 ± 3.3 mm Hg in AIT patients and 16.8 ± 2.8 mm Hg in TBS patients and the mean number of medications was 0.7 ± 1.0 and 1.7 ± 1.2, respectively (both P = .04). At 24 months, the IOP was 21 mm Hg or less without medications in 53% of AIT patients and 16.6% of TBS patients (P < .05). At that time, 17.6% of patients in the AIT group but no patient in the TBS group had an IOP reduction of 20% or more without medication. CONCLUSION: An exact matching comparison of AIT and TBS showed greater IOP reduction with fewer medications after AIT.

Outflow facility and extent of angle closure in a porcine model.

PURPOSE: To establish the extent of anterior chamber angle circumference needed to maintain a physiological outflow facility (C). This could create a model to investigate focal outflow regulation. METHODS: Twenty anterior segments of porcine eyes were assigned to five groups, each with a different degree of cyanoacrylate-mediated angle closure: 90° (n = 4), 180° (n = 4), 270° (n = 4), 360° (n = 4), and four unoccluded control eyes. The outflow facility was measured at baseline, 3, 12, 24, and 36 h after angle closure. Outflow patterns were evaluated with canalograms and the histomorphology was compared. RESULTS: Baseline outflow facilities of the five groups were similar (F = 0.922, p = 0.477). Occlusion of 360° induced a significant decrease in facility from baseline at all time-points (p ≤ 0.023 at 3, 12, 24, and 36 h). However, no difference from baseline was found in any of the partially occluded (0-270°) groups (F ≥ 0.067, p ≥ 0.296 at 3, 12, 24, and 36 h). The canalograms confirmed the extent of occlusion with flow through the unblocked regions. Histology revealed no adverse effects of blockage on the TM or aqueous plexus in the unoccluded angle portions. The unoccluded TM appeared normal. CONCLUSION: Cyanoacrylate-mediated angle occlusion created a reproducible angle closure model. Ninety degrees of unoccluded anterior chamber angle circumference was sufficient to maintain physiological outflow. This model may help understand how outflow can be regulated in healthy, nonglaucomatous TM.

Impact of pigment dispersion on trabecular meshwork cells.

PURPOSE: Dysfunction of the trabecular meshwork (TM) in pigmentary glaucoma contributes to increased aqueous humor outflow resistance and intraocular pressure. In this study, we investigated the effect of pigment dispersion on trabecular meshwork cells. METHODS: Porcine TM cells from ab interno trabeculectomy specimens were exposed to pigment dispersion, then, analyzed for changes in morphology, immunostaining, and ultrastructure. Their abilities to phagocytose migrate, and contraction was quantified. An expression microarray, using 23,937 probes, and a pathway analysis were performed. RESULTS: Stress fiber formation was increased in the pigment dispersion group (P) (60.1 ± 0.3%, n = 10) compared to control (C) (38.4 ± 2.5%, n = 11, p < 0.001). Phagocytosis declined (number of cells with microspheres in P = 37.0 ± 1.1% and in C = 68.7 ± 1.3%, n = 3, p < 0.001) and migration was reduced after 6 h (cells within the visual field over 6 h in P = 28.0.1 ± 2.3 (n = 12) and in C = 40.6 ± 3.3 (n = 13), p < 0.01). Pigment induced contraction at 24 h onwards (p < 0.01). Microarray analysis revealed that Rho signaling was central to these responses. CONCLUSION: Exposure of TM cells to pigment dispersion resulted in reduced phagocytosis and migration, as well as increased stress fiber formation and cell contraction. The Rho signaling pathway played a central and early role, suggesting that its inhibitors could be used as a specific intervention in treatment of pigmentary glaucoma.

RKI-1447, a Rho kinase inhibitor, causes ocular hypotension, actin stress fiber disruption, and increased phagocytosis.

PURPOSE: This study investigated the hypotensive effect of RKI-1447, a Rho kinase inhibitor, in a porcine ex vivo pigmentary glaucoma model. METHODS: Twenty-eight porcine anterior chambers were perfused with medium supplemented with 1.67 × 107 pigment particles/ml for 48 h before treatment with RKI-1447 (n = 16) or vehicle control (n = 12). Intraocular pressure (IOP) was recorded and outflow facility was calculated. Primary trabecular meshwork cells were exposed to RKI-1447 or vehicle control; effects on the cytoskeleton, motility, and phagocytosis were evaluated. RESULT: Compared to baseline, the perfusion of pigment caused a significant increase in IOP in the RKI-1447 group (P = 0.003) at 48 h. Subsequent treatment with RKI-1447 significantly reduced IOP from 20.14 ± 2.59 to 13.38 ± 0.91 mmHg (P = 0.02). Pigment perfusion reduced the outflow facility from 0.27 ± 0.03 at baseline to 0.18 ± 0.02 at 48 h (P < 0.001). This was partially reversed with RKI-1447. RKI-1447 caused no apparent histological changes in the micro- or macroscopic TM appearance. RKI-1447-treated primary TM cells showed significant disruption of the actin cytoskeleton both in the presence and absence of pigment (P < 0.001) but no effect on TM migration was observed. Pigment-treated TM cells exhibited a reduction in TM phagocytosis, which RKI-1447 reversed. CONCLUSION: RKI-1447 significantly reduces IOP by disrupting TM stress fibers and increasing TM phagocytosis. These features may make it useful for the treatment of secondary glaucomas with an increased phagocytic load.