ABSTRACT
Purpose@#We report two cases of non-arteritic ischemic optic neuropathy (NAION) following extracorporeal membrane oxygenation (ECMO) treatment.Case summary: (Case 1) A 36-year-old man underwent ECMO treatment. Upon regaining consciousness, he complained of a darkened peripheral visual field and was subsequently referred to an ophthalmologist. His best-corrected visual acuity was 0.9 in the right eye and 0.8 in the left eye. The intraocular pressure measured 12 mmHg in the right eye and 10 mmHg in the left eye; color vision was normal. A visual field test demonstrated concentric visual field defects in both eyes, and a fundus examination revealed a pale optic disc. Optical coherence tomography (OCT) indicated a decrease in retinal nerve fiber layer (RNFL) thickness. (Case 2) A 48-year-old woman underwent ECMO treatment. After regaining consciousness, she reported decreased vision in her right eye. Her best-corrected visual acuity was limited to hand motion in the right eye and was 1.2 in the left eye. A relative afferent pupillary defect in the right eye was observed. Color vision in the right eye was compromised, and a fundus examination revealed a pale optic disc. A visual field test demonstrated total visual field defect in the right eye, while OCT showed decreases in both the RNFL thickness and the ganglion cell-inner plexiform layer thickness of the right eye. Magnetic resonance imaging (MRI) revealed high signal intensity and abnormal enhancement in the right retrobulbar optic nerve. @*Conclusions@#In cases where vision loss and visual field defects are observed following ECMO treatment, differential diagnoses for ischemic optic neuropathy are warranted.
ABSTRACT
Free-living amoebas (FLAs) can cause severe disease in humans and animals when they become infected. However, there are no accurate survey reports on the prevalence of FLAs in Korea. In this study, we collected 163 tap water samples from buildings, apartments, and restrooms of highway service areas in 7 Korean provinces with high population density. All these buildings and facilities have water storage tanks in common. The survey was separated into categories of buildings, apartments, and highway service areas. Five hundred milliliters of tap water from each building was collected and filtered with 0.2 µm pore filter paper. The filters were incubated in agar plates with heated E. coli at 25°C. After axenization, genomic DNA was collected from each FLA, and species classification was performed using partial 18S-rDNA PCR-sequencing analysis. We found that 12.9% of tap water from buildings with storage tanks in Korea was contaminated with FLAs. The highway service areas had the highest contamination rate at 33.3%. All of the FLAs, except one, were genetically similar to Vermamoeba vermiformis (Hartmannella vermiformis). The remaining FLA (KFA21) was very similar to Acanthamoeba lugdunensis (KA/E26). Although cases of human infection by V. vermiformis are very rare, we must pay attention to the fact that one-third of tap water supplies in highway service areas have been contaminated.