Ocular infections associated with atypical mycobacteria: A review.

Atypical mycobacteria or non-tuberculous mycobacteria (NTM) are a group of acid-fast bacteria that are pathogenic to different parts of the eye. The organisms can cause a spectrum of ocular infections including keratitis, scleritis, uveitis, endophthalmitis and orbital cellulitis. Trauma, whether surgical or nonsurgical, has the highest correlation with development of this infection. Common surgeries after which these infections have been reported include laser in situ keratomileusis (LASIK) and scleral buckle surgery. The organism is noted to form biofilms with sequestration of the microbe at different inaccessible locations leading to high virulence. Collection of infective ocular material (corneal scraping/necrotic scleral tissue/abscess material/vitreous aspirate, etc.) and laboratory identification of the organism through microbiologic testing are vital for confirming presence of the infection and initiating treatment. In cluster infections, tracing the source of infection in the hospital setting via testing of different in-house samples is equally important to prevent further occurrences. Although the incidence of these infections is low, their presence can cause prolonged disease that may often be resistant to medical therapy alone. In this review, we describe the various types of NTM-ocular infections, their clinical presentation, laboratory diagnosis, management, and outcomes.

Case Series: Mixed Infectious Keratitis by Pythium insidiosum and Fungal Species.

SIGNIFICANCE: This case series is the first to illustrate mixed infection from Pythium sp. and fungal species in corneal ulcer. PURPOSE: This case series aimed to alert all toward the possibility of both Pythium sp. and fungal species infection in case of nonresponding corneal ulcer treated with either antifungals or antipythium drugs alone. Increased suspicion of mixed infection in case of nonresponding fungal/ Pythium keratitis may facilitate early and prompt management. CASE REPORTS: Six patients presented with signs of either fungal or Pythium keratitis. They underwent ophthalmological examinations, smear examinations, cultures, and polymerase chain reaction (PCR). Therapeutic penetrating keratoplasty was performed in cases where symptoms worsened after treatment with either antifungal or antipythium drugs. The half corneal button (HCB) was shared for histopathological and microbiological examinations. In the first case, smear examination from corneal scraping (CS) revealed Pythium -like filaments, which were confirmed with PCR; however, Aspergillus nidulans grew in culture. In the second case, iodine-potassium iodide (IKI) staining was positive for Pythium ; however, PCR was positive for both Pythium and fungus, which was further confirmed by DNA sequencing. In the third case, IKI staining and HCB were positive for Pythium ; however, PCR was positive for fungus, which was identified as Candida saitoana with DNA sequencing. In the fourth case, Pythium grew in the CS culture; however, Candida sp. grew in the HCB culture. In the fifth case, Cladosporium sp. grew in culture from CS; however, Pythium insidiosum grew from the anterior chamber exudate after therapeutic penetrating keratoplasty. In the sixth case, smear examination revealed septate fungal filaments, and Cladosporium sp. grew in culture; however, HCB on histopathological examination showed features of Pythium keratitis. CONCLUSIONS: In unresponsive cases of Pythium or fungal keratitis, diagnostic modalities such as IKI and PCR should be implemented as a routine practice, in addition to smears and cultures.

Assessment of SARS-CoV-2 virus in the tear secretion of conjunctivitis patients during COVID-19 pandemic.

Purpose: : To determine the presence of SARS-CoV-2 virus in the tear secretion of conjunctivitis patients during the COVID-19 pandemic. Methods: This observational, cross-sectional study was conducted in clinically diagnosed patients with conjunctivitis attending the outpatient services of our institute from July 2021 to December 2021. The tear samples were collected from patients using Schirmer's strips or capillary tubes to detect the presence of SARS-CoV-2 by real-time PCR assay. COVID-19 vaccination and infection status, visual acuity, and clinical features were documented in all cases. Results: A total of 111 patients with symptoms of conjunctivitis were included during the study period. The mean age was 41.1 ± 13.1 years, and the mean duration of symptoms was 7.1 ± 4.4 days, with 74% males. Conjunctival congestion was mild in 69 (62.1%) patients, moderate in 30 (27%) patients, and severe in 12 (10.8%) patients. All except four had superficial punctate keratitis (SPK). Five (4.3%) patients were positive for SARS-CoV-2 RNA in their tear samples. All had mild-moderate conjunctival congestions with variable papiliofollicular reaction and SPKs, superficial hemorrhages were seen in three and pseudomembrane in one patient. They were followed up with telemedicine and three of them developed mild COVID-19-related symptoms and recovered after in-home quarantine. None of them had a previous history of COVID-19 infection and all had received COVID-19 vaccination within 2 weeks to 2 months. Conclusion: SARS-CoV-2 transmission through ocular secretion of conjunctivitis patients cannot be ignored and appropriate COVID-19-preventive behavior should be followed in ocular settings.

Microsporidia-induced stromal keratitis: a new cause of presumed immune stromal (interstitial) keratitis.

BACKGROUND AND OBJECTIVE: To describe the clinical features, diagnosis and management of immune stromal keratitis/interstitial keratitis (IK) associated with microsporidial epithelial keratitis. METHODS: Between October 2020 and January 2021, medical records of IK patients microbiologically proven as microsporidia from samples collected from corneal epithelium on smear examination, and/ or molecular analysis were reviewed. Demography, clinical profile and treatment were analysed. Real-time PCR (RT-PCR) for adenovirus (ADV), Epstein-Barr virus (EBV), herpes simplex virus (HSV) and varicella-zoster virus (VZV) was done. RESULTS: Twenty of 152 (13%) microbiologically proven cases of microsporidial keratitis were diagnosed as IK during the study period, the mean age and duration of symptoms were 35.7±11.4 years and 46.3±27.7 days, respectively. Half had predisposing risk factors, like trauma; and 30% had prior recurrences. One-fourth of patients were using antivirals on presentation. Characteristic presentations included disciform keratitis(n=12), incomplete/complete ring(n=5), and combination(n=3), along with variable subepithelial infiltrates (n=14). All cases had stromal oedema, with an intact epithelium and fine pigment dusting on endothelium. Corneal epithelial scrapings had scanty microsporidia spores in smears of 17/20 (85%), and pan-microsporidial DNA was identified in 14/20 (70%), with Vittaforma corneae by sequencing in 11/20 (55%). Other viruses detected were ADV (14,70%), VZV (2,10%), EBV (1,5%) and HSV (1,5%). Rapid resolution of inflammation and oedema within 2 weeks of starting steroids was seen in all cases. CONCLUSION: Microsporidia epithelial keratitis induced stromal inflammatory keratitis; is distinguished from microsporidial keratoconjunctivitis and stromal keratitis, by characteristic clinical features, and response to topical steroids.

Past, present, and prospects in microsporidial keratoconjunctivitis- A review.

Ocular microsporidiosis comprises two entirely different spectra of disease as keratoconjunctivitis and stromal keratitis. Microsporidial keratoconjunctivitis (MKC) has been increasingly reported in the past two decades, probably due to raised awareness, simpler diagnostic procedures, and a better understanding of the clinical presentation. It is characterized by the presence of raised, coarse, punctate, multifocal, round to oval, greyish-white corneal epithelial lesions which usually evolve into nummular scars before resolution. Conjunctivitis seen is non-purulent and of mild-moderate intensity, with mixed papillary-follicular reaction. The mode of transmission and pathogenesis is poorly understood. Despite lack of inflammatory response, uncommon associations reported were- endotheliitis, corneal edema, limbitis, uveitis, and sub-epithelial infiltrates. There has been no consensus on the management of MKC. It varies from the use of multiple antimicrobial agents to simple lubricants. The majority of the disease goes underdiagnosed or misdiagnosed and treated as adenoviral keratoconjunctivitis, with topical steroids or anti-virals empirically. Changing trends have been noticed in the pattern of infection, possibly with increasing evidence of Vittaforma corneae as causative organisms, previously reported to cause stromal keratitis. An elaborate review of the past and present literature on MKC is provided in this review article, along with gaps in knowledge, and future directions of research.

Globicatella sanguinis Endophthalmitis in a Patient from India.

A 55-year-old lady with bamboo stick injury to her right eye suffered corneal laceration with retained wooden foreign body in the anterior chamber. In the first-sitting corneal laceration repair, lens aspiration with foreign body removal was done. Two days later, she developed signs and symptoms of endophthalmitis for which pars plana vitrectomy with intravitreal antibiotic injection was done. Smear examination of vitreous sample revealed the presence of Gram-positive cocci in pairs and short chains on Gram's stain on the same day. Confluent white, moist, and alpha-hemolyticus bacterial colonies appeared over the inoculum on blood agar and chocolate plates on the next day, which later was identified as Globicatella sanguinis by VITEK-2 compact system. To our knowledge, this is the second reported case of Globicatella-related endophthalmitis; the outcome was favourable in the incumbent case owing to an early intervention and isolate being susceptible to vancomycin.

Diagnostic Performance and Clinical Utility of Conventional PCR Assay in Early Diagnosis of COVID-19 Associated Rhino-Orbito-Cerebral Mucormycosis.

Early diagnosis and treatment of rhino-orbital-cerebral mucormycosis (ROCM) are crucial. Potassium hydroxide with Calcofluorwhite (KOH + CFW) smears can demonstrate the fungal hyphae, but mixed infections caused by both mucorales and non-mucorales pose a diagnostic challenge. Polymerase chain reaction (PCR) can detect mixed infections and differentiate mucorales from non-mucorales. This study aimed to evaluate the utility of a single reaction PCR in the diagnosis of ROCM and the efficacy of nasal biopsy and endonasal swab in the detection of fungus. Sixty-six clinical samples were collected from 33 patients and were subjected to KOH + CFW smear, culture and PCR. PCR was performed using pan-fungal primers targeting the 28S large subunit rRNA gene, and the amplified products were further sequenced to identify the fungi. KOH + CFW smear, culture and PCR detected mucorales in 54.6%, 27.3% and 63.6% patients, respectively. PCR detected mixed infection in 51.5% patients compared to 9.1% by KOH + CFW smear. PCR detected fungus in 90% of nasal biopsies and 77.8% of endonasal swabs. Rhizopus spp. was the most common fungi identified in 43.2% of PCR-positive samples. PCR is effective in detecting mixed infection and in the diagnosis of ROCM. Nasal biopsies had better fungal detection rates than endonasal swabs.

Use of different stains for microscopic evaluation for the diagnosis of Pythium keratitis.

PURPOSE: To evaluate the efficacy of various staining techniques for detection of Pythium in keratitis cases. METHODS: Data of nineteen consecutive culture-positive cases of Pythium keratitis were retrospectively analysed. Corneal scrapings and corneal buttons (in the cases which underwent therapeutic penetrating keratoplasty [TPK]) were sent for microbiological and histopathological examination. The direct smears were stained with Potassium hydroxide and calcofluor white (KOH â€‹+ â€‹CFW), Gram and Iodine-Potassium Iodide-Sulphuric Acid (IKI-H2SO4) stains. The corneal buttons were stained with Gomori's Methanamine Silver (GMS), Periodic Acid-Schiff (PAS) and Iodine-Potassium Iodide-Sulphuric Acid (IKI-H2SO4) stains. The positivity of various stains in detecting Pythium was studied. RESULTS: Gram and KOH â€‹+ â€‹CFW staining from smear was done in 16 out of 19 (84.2%) cases. KOH â€‹+ â€‹CFW and Gram stains were suggestive of Pythium in 10 (62.5%) and 7 (43.8%) cases, respectively. IKI-H2SO4 staining in scraping samples was positive for Pythium in all the 4 (100%) cases in which it was performed. Half corneal buttons were positive for Pythium with IKI-H2SO4 stain as well as GMS stain in all the 18 cases that underwent TPK (100%). PAS stain showed weak to faint pink staining of Pythium filaments in 7 out of 18 cases (38.9%). CONCLUSION: IKI-H2SO4 stain followed by KOH â€‹+ â€‹CFW stain detects Pythium filaments most accurately in corneal scraping samples from keratitis patients, although the differences were not statistically significant. The positivity of the stains depends on astute observation by an experienced ocular microbiologist and pathologist.

Fulminant fungal endogenous endophthalmitis following SARS-CoV-2 infection: A case report.

Systemic corticosteroids and immunocompromised state following SARS-CoV-2 infection can predispose individuals to endogenous endophthalmitis. A 66-year-old gentleman presented with complaints of diminution of vision and redness one week post discharge after hospitalization for COVID-19 infection. Clinical examination suggested fulminant endogenous endophthalmitis which responded poorly even after aggressive treatment requiring evisceration. Culture and gene sequenced analysis confirmed Aspergillus fumigatus to be the causative organism. A high degree of suspicion is warranted in the presence of recent onset of floaters in COVID-19-infected individuals to facilitate early diagnosis and outcomes.

Multiplicative Holts Winter Model for Trend Analysis and Forecasting of COVID-19 Spread in India.

The surge of the novel COVID-19 caused a tremendous effect on the health and life of the people resulting in more than 4.4 million confirmed cases in 213 countries of the world as of May 14, 2020. In India, the number of cases is constantly increasing since the first case reported on January 30, 2020, resulting in a total of 81,997 cases including 2649 deaths as of May 14, 2020. To assist the government and healthcare sector in preventing the transmission of disease, it is necessary to predict the future confirmed cases. To predict the dynamics of COVID-19 cases, in this paper, we project the forecast of COVID-19 for five most affected states of India such as Maharashtra, Tamil Nadu, Delhi, Gujarat, and Andhra Pradesh using the real-time data. Using Holt-Winters method, a forecast of the number of confirmed cases in these states has been generated. Further, the performance of the method has been determined using RMSE, MSE, MAPE, MAE and compared with other standard algorithms. The analysis shows that the proposed Holt-Winters model generates RMSE value of 76.0, 338.4, 141.5, 425.9, 1991.5 for Andhra Pradesh, Maharashtra, Gujarat, Delhi and Tamil Nadu, which results in more accurate predictions over Holt's Linear, Auto-regression (AR), Moving Average (MA) and Autoregressive Integrated Moving Average (ARIMA) model. These estimations may further assist the government in employing strong policies and strategies for enhancing healthcare support all over India.

Role of intelligent computing in COVID-19 prognosis: A state-of-the-art review.

The World Health Organization (WHO) declared novel coronavirus 2019 (COVID-19), an infectious epidemic caused by SARS-CoV-2, as Pandemic in March 2020. It has affected more than 40 million people in 216 countries. Almost in all the affected countries, the number of infected and deceased patients has been enhancing at a distressing rate. As the early prediction can reduce the spread of the virus, it is highly desirable to have intelligent prediction and diagnosis tools. The inculcation of efficient forecasting and prediction models may assist the government in implementing better design strategies to prevent the spread of virus. In this paper, a state-of-the-art analysis of the ongoing machine learning (ML) and deep learning (DL) methods in the diagnosis and prediction of COVID-19 has been done. Moreover, a comparative analysis on the impact of machine learning and other competitive approaches like mathematical and statistical models on COVID-19 problem has been conducted. In this study, some factors such as type of methods(machine learning, deep learning, statistical & mathematical) and the impact of COVID research on the nature of data used for the forecasting and prediction of pandemic using computing approaches has been presented. Finally some important research directions for further research on COVID-19 are highlighted which may facilitate the researchers and technocrats to develop competent intelligent models for the prediction and forecasting of COVID-19 real time data.

Characterisation and expression analysis of trophozoite and cyst proteins of Acanthamoeba spp. isolated from Acanthamoeba keratitis (AK) patient.

The study was carried out to characterise and analyze the expression pattern of proteins of infective trophozoite and cyst forms of Acanthamoeba spp. isolated from an amoebic keratitis patient. Protein was isolated from the trophozoites and cysts of Acanthamoeba spp. isolates and subjected to SDS PAGE, 2D PAGE analysis where a large number of protein bands and protein spots were observed. Four prominent protein spots i.e. 2 from trophozoites and 2 from cysts that appeared more intense compared to the corresponding spots in other corresponding gel were excised from the 2D PAGE gels and analysed by MALDI-TOF/TOF MS assay and Mascot search software. Protein spots from trophozoites were identified as "hypothetical protein ACA1" and "eukaryotic porin protein" and those from cysts were identified as "chaperone protein DnaK" and "chaperonin protein" respectively. Proteomic results of 4 proteins were further validated by reverse genomics using quantitative real time PCR assay which showed a 1388 fold and 4.35 fold increase in expression of "hypothetical protein ACA1" gene and "eukaryotic porin protein" gene respectively in trophozoites compared to cysts and a 15 fold and 12.36 fold increase in expression of "chaperone protein DnaK" gene and "chaperonin protein" gene respectively in cysts compared to trophozoites. "Hypothetical protein ACA1" of trophozoites, whose function is unknown might have some important role in the parasite division and pathogenicty of Acanthamoeba spp. which needs further study. As trophozoites are the active and feeding form of Acanthamoeba spp., "eukaryotic porin" proteins may have some important role in efflux of toxic metabolites and exudates from interior of cell to outside along with some role in pathogenicity. Similarly proteins such as "chaperone protein DnaK" and "chaperonin protein" which belongs to group of heat shock proteins may have a role in folding of cyst specific proteins in cyst which needs further study.