Endogenous Nocardial Endophthalmitis Misdiagnosed as Giant Cell Arteritis.

PURPOSE: Endogenous endophthalmitis is uncommon but potentially dangerous. We present a fatal presentation of endogenous Nocardial endophthalmitis in the context of steroid use for treatment of giant cell arteritis. CASE PRESENTATION: An 84-year-old Caucasian female presented to the local emergency room with severe headaches, myalgia and shoulder and calf muscle pain. She was treated for a presumed diagnosis of giant-cell arteritis with corticosteroids and subsequently developed an intense retro-orbital pain in the right eye. Fundus examination revealed a white, vascularized chorioretinal mass at the equator of the eye in the inferotemporal quadrant. Antibiotics were given and a vitrectomy was performed. The culture of the vitreous showed Nocardia nova and a diagnosis of disseminated Nocardiosis was made. CONCLUSION AND SIGNIFICANCE: Although uncommon, it is important that ophthalmologists are aware of Nocardial infections as a differential diagnosis of retinal mass, particularly in immunocompromised patients.

ProMoIJ: A new tool for automatic three-dimensional analysis of microglial process motility.

Microglia, the immune cells of the central nervous system, continuously survey the brain to detect alterations and maintain tissue homeostasis. The motility of microglial processes is indicative of their surveying capacity in normal and pathological conditions. The gold standard technique to study motility involves the use of two-photon microscopy to obtain time-lapse images from brain slices or the cortex of living animals. This technique generates four dimensionally-coded images which are analyzed manually using time-consuming, non-standardized protocols. Microglial process motility analysis is frequently performed using Z-stack projections with the consequent loss of three-dimensional (3D) information. To overcome these limitations, we developed ProMoIJ, a pack of ImageJ macros that perform automatic motility analysis of cellular processes in 3D. The main core of ProMoIJ is formed by two macros that assist the selection of processes, automatically reconstruct their 3D skeleton, and analyze their motility (process and tip velocity). Our results show that ProMoIJ presents several key advantages compared with conventional manual analysis: (1) reduces the time required for analysis, (2) is less sensitive to experimenter bias, and (3) is more robust to varying numbers of processes analyzed. In addition, we used ProMoIJ to demonstrate that commonly performed 2D analysis underestimates microglial process motility, to reveal that only cells adjacent to a laser injured area extend their processes toward the lesion site, and to demonstrate that systemic inflammation reduces microglial process motility. ProMoIJ is a novel, open-source, freely-available tool which standardizes and accelerates the time-consuming labor of 3D analysis of microglial process motility.

Fluoxetine treatment affects the inflammatory response and microglial function according to the quality of the living environment.

It has been hypothesized that selective serotonin reuptake inhibitors (SSRIs), the most common treatment for major depression, affect mood through changes in immune function. However, the effects of SSRIs on inflammatory response are contradictory since these act either as anti- or pro-inflammatory drugs. Previous experimental and clinical studies showed that the quality of the living environment moderates the outcome of antidepressant treatment. Therefore, we hypothesized that the interplay between SSRIs and the environment may, at least partially, explain the apparent incongruence regarding the effects of SSRI treatment on the inflammatory response. In order to investigate such interplay, we exposed C57BL/6 mice to chronic stress to induce a depression-like phenotype and, subsequently, to fluoxetine treatment or vehicle (21days) while being exposed to either an enriched or a stressful condition. At the end of treatment, we measured the expression levels of several anti- and pro-inflammatory cytokines and inflammatory mediators in the whole hippocampus and in isolated microglia. We also determined microglial density, distribution, and morphology to investigate their surveillance state. Results show that the effects of fluoxetine treatment on inflammation and microglial function, as compared to vehicle, were dependent on the quality of the living environment. In particular, fluoxetine administered in the enriched condition increased the expression of pro-inflammatory markers compared to vehicle, while treatment in a stressful condition produced anti-inflammatory effects. These findings provide new insights regarding the effects of SSRIs on inflammation, which may be crucial to devise pharmacological strategies aimed at enhancing antidepressant efficacy by means of controlling environmental conditions.