Unilateral conjunctival Classic Kaposi Sarcoma following a COVID 19 booster.

Purpose: We describe a case of Classic Kaposi's sarcoma in a functionally monocular patient following a COVID19 vaccine booster and provide compelling evidence that suggests the booster was a relevant co-factor in the initiation of the disease process. Observations: The patient presented with red, irritated conjunctival area described as "bubbling" in her right eye. While her past medical history includes hypercholesterolemia and hypertension, she had no history of a compromised immune system. Her ophthalmologic history is more complex including treatment for glaucoma. The patient has 20/20 uncorrected vision OD and LP OS. Due to her ocular co-morbidities, the patient initially received interferon alpha 2-B qid for 6 weeks. However, topical therapy failed to decrease the size of the conjunctival lesions. After referral to Radiation Oncology, the right eye/orbit was treated with electron beam therapy for 1 month which caused a marked decrease in the size and vascularity of the conjunctival lesions. A slow improvement continued during followup. Conclusion and importance: In that the vaccine booster preceded the cancer, it appears etiologic to the appearance of Kaposi's sarcoma. The patient's monocular vision and glaucoma complicated her treatment. This case expands on current concepts of cofactors needed for the development of Kaposi's sarcoma in that vaccine booster administration was relevant to tumor progression and both clinical and mechanistic evidence is presented to support this hypothesis.

The impact of polymerase chain reaction (PCR) on diagnosis and management of infectious uveitis at a tertiary care facility.

BACKGROUND: Polymerase Chain Reaction (PCR) is a well-accepted adjunct in the management of infectious uveitis. In turn, few reports in the literature have evaluated how PCR then impacts patient care. This study aims to evaluate the impact of PCR sampling on diagnosis and treatment of infectious uveitidies at a large tertiary care facility. MAIN BODY: This is a retrospective, observational study of patients with aqueous and vitreous PCR samples obtained from 2014 to 2019. The study was undertaken at a single institution. At least one follow up visit following results of PCR testing was required for inclusion. If a patient had multiple PCR samples taken, only the first sample was included. The patients were divided into three categories based on pre-sampling diagnosis. A chi-square test was used to analyze the data. 108 cases were available for analysis. PCR did not change diagnosis or management in any of the cases where pre-sampling diagnosis carried a high clinical suspicion for negative PCR. Overall, the results of PCR testing had a more significant impact on diagnosis in those cases where pre-sampling diagnosis was unknown versus those where it was confirmatory in nature, thus presumed to be related to an infectious entity tested by PCR (74% vs. 29%, p = 0.00006). The rate of treatment change based on PCR was similar between those cases where there was a high clinical suspicion for positive PCR and those where pre-sampling diagnosis was unknown (32% vs. 33%, p = 0.95). Further analyzing specimens separately depending on source of sample, this pattern persisted for aqueous samples, with PCR showing a more significant impact on diagnosis in those cases where the diagnosis was unknown versus those where sampling was confirmatory (86% vs. 31%, p = 0.00004). The rate of change in treatment between the two groups was similar (35% vs. 31%, p = 0.79). Vitreous samples followed a similar pattern with a higher rate of diagnosis change for those cases where pre-sampling diagnosis was unknown and a similar rate in treatment change between the two groups, however this did not reach statistical signifigance (44% vs. 25%, p = 0.28; 27% vs. 33%, p = 0.74). CONCLUSION: There is no well-defined algorithm as to when to employ PCR testing in uveitis. As expected, in our experience, it has the largest impact on diagnosis when the diagnosis is unknown, however even when confirmatory in nature, it continues to impact patient management.

Quantitative Study of Human Scleral Melanocytes and Their Topographical Distribution.

PURPOSE: While fibroblasts constitute the main cell component of the sclera, the purpose of the present study was to investigate the cell densities of melanocytes at different regions of the sclera, and to compare them with associated scleral fibroblast densities in human donor eye sections. METHODS: . Paraffin-embedded sections of sclera from 21 human eyes were stained with hematoxylin-eosin (H&E) and immunohistochemical staining (S-100/AEC). Scleral melanocyte and fibroblast numbers were counted in different regions of the sclera. The relationship between the melanocyte density and iris pigmentation was also analyzed. RESULTS: . Melanocytes were found in the posterior region of the sclera, especially around the vessels and nerves in emmissarial canals, whereas no or rare melanocytes were found in equatorial and anterior regions. In H&E sections, melanocyte densities in eyes with light-colored irides were significantly less than in eyes with medium or dark-colored irides (P < .05). In S-100-stained sections, more melanocytes could be detected than those in the H&E sections in light-colored eyes (P < .05), but not in medium or dark-colored eyes (P > .05). The numbers of scleral fibroblasts were relatively stable in different regions. In the posterior scleral region, the numbers of fibroblasts were slightly higher than the number of melanocytes, however, this differences were not statistically significant (P > .05). CONCLUSION: . Notable numbers of melanocytes were present in the posterior sclera suggesting that these cells may play a role in ocular physiology and in the pathogenesis of various disorders of the sclera.

Hypoxia-induced vascular endothelial growth factor secretion by retinal pigment epithelial cells is inhibited by melatonin via decreased accumulation of hypoxia-inducible factors-1α protein.

BACKGROUND: Hypoxia is the most important stimulus leading to up-regulation of vascular endothelial growth factor (VEGF) in the retina via elevation of hypoxia-inducible factors-1α (HIF-1α) protein. The purpose of this study was to test the effects of melatonin on the expression of VEGF and HIF-1α in the cultured human retinal pigment epithelial (RPE) cells under normoxia and hypoxia. METHOD: An in vitro RPE cell hypoxia model was established by placing cells under 1% oxygen pressure or by adding cobalt chloride (CoCl2 ) to the culture medium. RPE cells and conditioned media were collected from cultures treated with and without melatonin under normoxia and hypoxia. The protein and RNA levels of VEGF and HIF-1α were measured by ELISA kits and RT-PCR, respectively. RESULT: Hypoxia induced a significant increase of expression and secretion of VEGF and accumulation of HIF-1α protein in RPE cells (P < 0.05). Melatonin at 10-5 to 10-8 M significantly inhibited hypoxia-induced expression, the secretion of VEGF and the accumulation of HIF-1α protein (P < 0.05), but not affected expression of VEGF and HIF-1α under normoxia (P > 0.05). CONCLUSION: This study suggests that melatonin may have potential value in the prevention and treatment of various retinal diseases associated with increase of VEGF, vascular leakage and angiogenesis.

Nonlethal Levels of Zeaxanthin Inhibit Cell Migration, Invasion, and Secretion of MMP-2 via NF-κB Pathway in Cultured Human Uveal Melanoma Cells.

Zeaxanthin at nonlethal dosages (3-10 µM) significantly inhibited the cell migration of cultured uveal melanoma cells (C918 cell line) as determined by wound healing assay and Boyden chamber assay. Matrigel invasion assay showed that cell invasion of uveal melanoma cells could be significantly inhibited by zeaxanthin. Secretion of MMP-2 by melanoma cells was significantly inhibited by zeaxanthin in a dose-dependent manner as measured by ELISA kit. Zeaxanthin also significantly inhibited the NF-κB levels in nuclear extracts of the UM cells, which is the upstream of the MMP-2 secretion. These results suggest that zeaxanthin might be a potentially therapeutic approach in the prevention of metastasis in uveal melanoma.

A Hyalinized Trichilemmoma of the Eyelid in a Teenager.

A 16-year-old African American male, the youngest patient to date, presented with a well-circumscribed upper eyelid lesion. On excision, the dermal nodule was contiguous with the epidermis, displayed trichohyalin-like bodies in an expanded outer root sheath, and was composed chiefly of small cellular clusters separated by a prominent network of periodic acid Schiff -positive hyaline bands of basement membrane material. The tumor cells were positive for high molecular weight cytokeratins (CK) 5/6, CK14, and CK34ßE12 and were negative for CK7, carcinoembryonic antigen and epithelial membrane antigen. Negative S100, glial fibrillary acidic protein, and smooth muscle actin immunoreactions ruled out a myoepithelial lesion. The Ki-67 proliferation index was <10%. The diagnosis was a hyalinized trichilemmoma, contrasting with the more common lobular type. As an isolated lesion, trichilemmoma does not portend Cowden syndrome.