A case of ocular infection with Onchocerca lupi
 in a dog from Germany

Keratitis and conjunctivitis (infections of the cornea or conjunctiva) are ocular infections caused by various bacteria, fungi, viruses or parasites; bacteria, however, are usually prominent. Systemic conditions such as alcoholism, diabetes, debilitating disease, AIDS and immunosuppressive therapy can lead to increased susceptibility but trauma and contact lens use are very important factors. Gram-negative bacteria are most frequently cultured in these situations and Pseudomonas aeruginosa is most usually isolated from culture-positive ulcers of patients using contact lenses. Smears for staining can be obtained with a special swab or spatula and Gram staining frequently guides choice of a therapeutic rinse prior to the report of the culture results upon which specific antibiotic therapy is based. In some cases staining of the direct smear may be diagnostic in situations where the culture will not grow. In these cases different types of stains occasionally assist in guiding therapy.

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Ocular Involvement of SARS-CoV-2 in a Polish Cohort of COVID-19-Positive Patients

International Journal of Environmental Research and Public Health ◽

10.3390/ijerph18062916 ◽

2021 ◽

Vol 18 (6) ◽

pp. 2916

Author(s):

Joanna Dolar-Szczasny ◽

Mario D. Toro ◽

Anna Dworzańska ◽

Tomasz Wójtowicz ◽

Izabela Korona-Glowniak ◽

...

Keyword(s):

Genetic Material ◽

Eye Disease ◽

Ocular Infection ◽

Ocular Involvement ◽

Consecutive Series ◽

Respiratory Involvement ◽

Ocular Symptoms ◽

Male Patients ◽

Tight Correlation ◽

Variable Efficiency

The coronavirus SARS-CoV-2 responsible for the current human COVID-19 pandemic has shown tropism toward different organs with variable efficiency, eyes included. The purpose of this study has been to investigate the presence of detectable SARS-CoV-2 infection in ocular swabs in patients affected by COVID-19. A consecutive series of 74 COVID-19-positive patients (age 21–89) were enrolled at two Polish COVID-19 hospitals for 4 months and were characterized by PCR for the presence of the SARS-CoV-2 genetic material in nasopharyngeal (NP) and ocular swabs, while their respiratory and ocular symptoms were noted. Almost 50% of them presented with severe/critical respiratory involvement, and some degree of eye disease. No tight correlation was observed between the presence of ocular and respiratory symptoms. Three male patients presenting with severe/critical lung disease tested positive in ocular swab, however with mild/moderate ocular symptoms. In conclusion, our study lends further support to the view that overt ocular infection by the SARS-CoV-2 virus is not such a frequent occurrence.

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Comparison of platforms for testing antibodies to Chlamydia trachomatis antigens in the Democratic Republic of the Congo and Togo

Scientific Reports ◽

10.1038/s41598-021-86639-8 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Sarah Gwyn ◽

Marcel S. Awoussi ◽

Ana Bakhtiari ◽

Rachel N. Bronzan ◽

Kathryn Crowley ◽

...

Keyword(s):

Chlamydia Trachomatis ◽

Democratic Republic ◽

Seroconversion Rate ◽

Public Health Problem ◽

Dried Blood Spots ◽

Ocular Infection ◽

Republic Of The Congo ◽

Lateral Flow Assays ◽

Serological Data ◽

Multiplex Bead

AbstractTrachoma, caused by repeated ocular infection with Chlamydia trachomatis (Ct), is targeted for elimination as a public health problem. Serological testing for antibodies is promising for surveillance; determining useful thresholds will require collection of serological data from settings with different prevalence of the indicator trachomatous inflammation—follicular (TF). Dried blood spots were collected during trachoma mapping in two districts each of Togo and Democratic Republic of the Congo. Anti-Ct antibodies were detected by multiplex bead assay (MBA) and three different lateral flow assays (LFA) and seroprevalence and seroconversion rate (SCR) were determined. By most tests, the district with > 5% TF (the elimination threshold) had five–sixfold higher seroprevalence and tenfold higher SCR than districts with < 5% TF. The agreement between LFA and MBA was improved using a black latex developing reagent. These data show optimization of antibody tests against Ct to better differentiate districts above or below trachoma elimination thresholds.

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Continuous Real-Time Motility Analysis of Acanthamoeba Reveals Sustained Movement in Absence of Nutrients

Pathogens ◽

10.3390/pathogens10080995 ◽

2021 ◽

Vol 10 (8) ◽

pp. 995

Author(s):

Allison Campolo ◽

Valerie Harris ◽

Rhonda Walters ◽

Elise Miller ◽

Brian Patterson ◽

...

Keyword(s):

Contact Lens ◽

Contact Lenses ◽

Axenic Culture ◽

Acanthamoeba Keratitis ◽

Ocular Infection ◽

Glass Coverslip ◽

E Coli ◽

Total Distance ◽

Care Systems ◽

Different Strains

Acanthamoeba keratitis is a serious ocular infection which is challenging to treat and can lead to blindness. While this pathogen is ubiquitous and can contaminate contact lenses after contact with water, its habits remain elusive. Understanding this organism’s natural behavior will better inform us on how Acanthamoeba colonize contact lens care systems. Acanthamoeba trophozoites were allowed to adhere to either a glass coverslip or non-nutrient agar (NNA) within a flow cell with nutrients (Escherichia coli or an axenic culture medium (AC6)) or without nutrients (Ringer’s solution). Images were taken once every 24 s over 12 h and compiled, and videos were analyzed using ImageJ Trackmate software. Acanthamoeba maintained continuous movement for the entire 12 h period. ATCC 50370 had limited differences between conditions and surfaces throughout the experiment. Nutrient differences had a noticeable impact for ATCC 30461, where E. coli resulted in the highest total distance and speed during the early periods of the experiment but had the lowest total distance and speed by 12 h. The Ringer’s and AC6 conditions were the most similar between strains, while Acanthamoeba in the E. coli and NNA conditions demonstrated significant differences between strains (p < 0.05). These results indicate that quantifiable visual tracking of Acanthamoeba may be a novel and robust method for identifying the movement of Acanthamoeba in relation to contact lens care products. The present study indicates that Acanthamoeba can undertake sustained movement for at least 12 h with and without nutrients, on both rough and smooth surfaces, and that different strains have divergent behavior.

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Pyrenochaeta keratinophila sp. nov., isolated from an ocular infection in Spain

Revista Iberoamericana de Micología ◽

10.1016/j.riam.2009.09.001 ◽

2010 ◽

Vol 27 (1) ◽

pp. 22-24 ◽

Cited By ~ 15

Author(s):

Gerard J.M. Verkley ◽

Josepa Gené ◽

Josep Guarro ◽

Juan J. Pérez-Santonja ◽

Alejandra E. Rodríguez ◽

...

Keyword(s):

Ocular Infection

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Fungal Keratitis in Northern Thailand: Spectrum of Agents, Risk Factors and Putative Virulence Factors

Journal of Fungi ◽

10.3390/jof7060475 ◽

2021 ◽

Vol 7 (6) ◽

pp. 475

Author(s):

Siriporn Chongkae ◽

Sirida Youngchim ◽

Joshua D. Nosanchuk ◽

Angkana Laliam ◽

Chulaluck Tangmonkongvoragul ◽

...

Keyword(s):

Virulence Factors ◽

Vision Loss ◽

Proteolytic Enzymes ◽

Tertiary Care ◽

Fungal Keratitis ◽

High Rate ◽

Ocular Infection ◽

Fungal Culture ◽

Care Hospital ◽

Northern Thailand

Fungal keratitis (FK) is a serious ocular infection that can result in various degrees of vision loss, including blindness. The aim of the study was to identify and retrospectively review all FK cases diagnosed between August 2012 and December 2020 at a tertiary care hospital in northern Thailand with a specific focus on epidemiologic features, including season, patient sex and age, the spectrum of pathogens, and presence of certain putative virulence factors. Of 1237 patients with corneal ulcers, 294 (23.8%) were confirmed by direct microscopic examination and/or fungal culture. For the positive cases, direct examinations of Calcofluor white (CW) stains and KOH mounts were found in 97.3% (286/294) and 76.5% (225/294), respectively (p < 0.05). Of the cases diagnosed by microscopy and culture, fungi were isolated in 152 (51.7%), with Fusarium spp. being the most frequently identified (n = 69, 45.5%) followed by dematiaceous fungi (n = 45, 29.6%) and Aspergillus spp. (n = 18, 11.8%). The incidence of FK was higher in the rainy season of July to October. The mean age was 54.4 ± 14.4 (SD) years, with a range of 9–88 years. Males (75.8%) were affected significantly more than females (24.2%) (p < 0.05). Of 294 patients, 132 (44.9%) were middle-aged adults (41–60 years) and 107 (36.4%) were older than 60 years. Trauma to the eye by soil or vegetative matter were the most common preceding factors (188/294; 64.0%). We assessed two virulence factors. First, 142 of the 152 culture-positive FK cases were due to molds, indicating that hyphal morphogenesis is extremely important in disease. We also demonstrated that fungal melanization occurs in the molds during the course of FK by applying a melanin-specific monoclonal antibody (MAb) that labeled fungal elements in corneal samples of patients, and melanin particles derived from the hyphae were also recovered after treatment of the samples with proteolytic enzymes, denaturant and hot concentrated acid. In summary, we demonstrate that northern Thailand has a high rate of FK that is influenced by season and males engaged in outside activities are at highest risk for disease. Moulds are significantly more commonly responsible for FK, in part due to their capacity to form hyphae and melanins. Future studies will examine models of fungal corneal interactions and assess additional factors of virulence, such as secreted enzymes, to more deeply decipher the pathogenesis of FK.

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Herpes Simplex Virus Type 1 Corneal Infection Results in Periocular Disease by Zosteriform Spread

Journal of Virology ◽

10.1128/jvi.75.11.5069-5075.2001 ◽

2001 ◽

Vol 75 (11) ◽

pp. 5069-5075 ◽

Cited By ~ 47

Author(s):

Bretton C. Summers ◽

Todd P. Margolis ◽

David A. Leib

Keyword(s):

Herpes Simplex Virus ◽

Herpes Simplex ◽

Skin Lesions ◽

Ocular Infection ◽

Trigeminal Ganglia ◽

Corneal Infection ◽

Recombinant Viruses ◽

Viral Spread ◽

Reporter Activity ◽

Simplex Virus

ABSTRACT In humans and animal models of herpes simplex virus infection, zosteriform skin lesions have been described which result from anterograde spread of the virus following invasion of the nervous system. Such routes of viral spread have not been fully examined following corneal infection, and the possible pathologic consequences of such spread are unknown. To investigate this, recombinant viruses expressing reporter genes were generated to quantify and correlate gene expression with replication in eyes, trigeminal ganglia, and periocular tissue. Reporter activity peaked in eyes 24 h postinfection and rapidly fell to background levels by 48 h despite the continued presence of viral titers. Reporter activity rose in the trigeminal ganglia at 60 h and peaked at 72 h, concomitant with the appearance and persistence of infectious virus. Virus was present in the periocular skin from 24 h despite the lack of significant reporter activity until 84 h postinfection. This detection of reporter activity was followed by the onset of periocular disease on day 4. Corneal infection with a thymidine kinase-deleted reporter virus displayed a similar profile of reporter activity and viral titer in the eyes, but little or no detectable activity was observed in trigeminal ganglia or periocular tissue. In addition, no periocular disease symptoms were observed. These findings demonstrate that viral infection of periocular tissue and subsequent disease development occurs by zosteriform spread from the cornea to the periocular tissue via the trigeminal ganglion rather than by direct spread from cornea to the periocular skin. Furthermore, clinical evidence is discussed suggesting that a similar mode of spreading and disease occurs in humans following primary ocular infection.

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