Infectious Scleritis - Clinical Characteristics, Causative Factors, and Treatment Outcomes in an Indian Population.

PURPOSE: To study the clinical features, causative factors and treatment outcomes in patients with infectious scleritis seen in India. METHODS: A retrospective study of all patients examined at a tertiary care center between August 2012 and March 2021. RESULTS: Forty-five patients (45 eyes; mean age 52.7 ± 17.5 years) were included in the study. The mean duration of symptoms was 3.1 ± 4.4 months. Inciting factors were found in 53.3% (injury: 33.3%; ocular surgery: 20.0%). The scleritis was predominantly anterior (97.8%), with multiple lesions in 40.0%, a solitary lesion in 31.1%, and diffuse in 28.9%. Associated features included uveitis (51.1%), keratitis (37.8%), hypopyon (15.6%), and endophthalmitis (6.7%). Causative organisms included bacteria (53.3%), fungi (35.6%), and presumed herpes virus (11.1%). All patients were treated with antimicrobial agents along with systemic corticosteroids where indicated. Surgical treatment included scleral debridement (37.8%), patch grafts (4.4%), and penetrating keratoplasty (2.2%). Complete resolution of scleritis was seen in 86.7%, with a mean duration of therapy of 2.9 ± 2.5 months. The mean follow-up was 8.3 ± 14.3 months. 51.1% of patients lost functional vision (<6/60). Causes of decreased vision included corneal scar, cataract, macular scar, glaucomatous optic atrophy, and phthisis bulbi. On bivariate analysis, poor visual acuity at presentation was associated with a worse visual outcome (p = 0.02). Other risk factors included necrotizing scleritis, multifocal scleritis, the presence of keratitis and uveitis. CONCLUSION: In our study, infectious scleritis resulted from bacterial and fungal infections. The scleritis resolved in most subjects, however, vision loss was frequent due to infection-related complications.

Paenibacillus lautus: A new foe in endogenous endophthalmitis.

PURPOSE: To discuss the diagnosis and management of a rare case of endogenous endophthalmitis (EE) caused by Paenibacillus lautus mimicking granulomatous uveitis in a child, highlighting the use of 16S rRNA gene amplicon sequencing as an accurate method to identify rare pathogens. METHOD: A retrospective chart review of the clinical presentation, microbiologic workup-including microscopy, culture, antibiotic susceptibility, and polymerase chain reaction for pathogen DNA of clinical samples-and the clinical management of the case were recorded. RESULT: A 13-year-old boy presented with decreased vision in the right eye for one month. On examination, he had uveitis with hypopyon and complicated cataract. The case underwent an anterior chamber tap followed by vitrectomy and lensectomy. The culture of the vitreous aspirate grew Gram-variable bacilli that could not be identified by conventional microbiological techniques. However, PCR-based sequencing of the 16S rRNA gene was performed, and the bacterium was identified as P. lautus. The patient subsequently developed rhegmatogenous retinal detachment, for which he underwent endo laser photocoagulation and oil tamponade. Four months later, silicone oil was removed, and an intraocular lens was implanted. At six weeks follow-up, the retina remained well attached, and intraocular pressure was maintained. CONCLUSION: P. lautus can cause EE and mimic granulomatous uveitis. Techniques such as 16S rRNA gene sequencing can significantly facilitate aetiological diagnosis in cases where conventional methods fail.

Sphingomonas paucimobilis: Navigating from Recurrent Hypopyon Anterior Uveitis to Endogenous Endophthalmitis: A Case Report.

PURPOSE: To report a case of endogenous endophthalmitis caused by Sphingomonas paucimobilis in a young male. MATERIALS AND METHODS: A retrospective case report. RESULTS: A 25-year-old male presented with reduced vision in the right eye and recurrent past episodes of hypopyon uveitis. The right eye had vision of counting fingers close to the face with cells, flare, and hypopyon in the anterior chamber with vitritis and exudates in the fundus. Blood investigations for tuberculosis, syphilis, toxoplasma, sarcoidosis, RA, ANA, HLA B27, and HLA B29 were negative. Anterior chamber tap investigations for herpes simplex viruses, varicella-zoster virus, cytomegalovirus, and toxoplasma, as well as Mycobacterium tuberculosis, yielded negative results. Ultrasound B-scan revealed a moderate number of low-reflective dot echoes in the vitreous, along with a few membranous echoes suggestive of vitritis. Blood culture and urine culture were negative. Since there was progressive deterioration, diagnostic and therapeutic vitrectomy was done with intravitreal antibiotics. The culture of the vitreous sample grew Sphingomonas paucimobilis. In the post-operative period, the patient developed retinal detachment, and re-surgery was done with a lensectomy, and the vision improved to 6/18 with contact lenses in the follow-up. CONCLUSION: This case report describes the distinct occurrence of endogenous endophthalmitis in an immunocompetent young male, which was previously reported only in peripartum cases. The clinical course is characterized by masquerading symptoms and recurrent episodes, despite the organism being of low virulence.

Endogenous fungal endophthalmitis following COVID-19 infection with microbiological and molecular biological correlation - A report of two cases.

This case report describes three eyes of two patients, who were diagnosed to have endogenous fungal endophthalmitis post coronavirus disease 2019 (COVID-19) infection. Both patients underwent vitrectomy with intravitreal anti-fungal injection. Intra-ocular samples confirmed the fungal etiology by conventional microbiological investigations and polymerase chain reaction in both cases. The patients were treated with multiple intravitreal and oral anti-fungal agents; however, vision could not be salvaged.

Role of polymerase chain reaction-based viral detection in pterygia.

Purpose: Pterygium is a fibrovascular disease that originates in the conjunctiva and commonly spreads to the corneal surface, thereby posing a threat to eyesight. Despite intensive research, the pathophysiology of this disease remains unclear. Recent research suggests that oncogenic viruses, such as human papillomavirus (HPV), cytomegalovirus, and Epstein-Barr virus (EBV), may play a role in pterygia development. Although there are questions concerning the function of oncogenic viruses in pterygium pathogenesis, existing research shows a lack of consensus on the subject, demonstrating the heterogeneity of pterygium pathophysiology. Therefore, we aimed to simultaneously detect the three common viral pathogens that have been reported in pterygium tissue obtained after excision. Methods: Thirty-five tissue specimens of pterygium from patients undergoing pterygium surgery (as cases) were analyzed for evidence of viral infection with multiplex polymerase chain reaction (PCR), and virus-specific real-time quantitative PCR was used for the samples that were detected positive by multiplex PCR. Results: Of the 35 patients, one sample was positive for EBV and two samples were positive for HPV. Further PCR-based DNA sequencing of the HPV PCR-positive product showed identity with HPV-16. Real-time quantitative PCR on samples that showed EBV or HPV positivity did not yield any detectable copy number. Conclusion: Our study results confirmed that PCR positivity could be due to transient flora, but it was not quantitatively significant to conclude as the causative factor of pterygium pathogenesis. However, additional studies with larger sample populations are warranted to fully determine the role of the virus in pterygium.

Tuberculous Scleritis and Multidrug Resistance.

PURPOSE: To present a case of necrotizing sclerokeratitis in a patient with multidrug-resistant tuberculosis and study the challenges in diagnosis and management of anterior tuberculous scleritis. METHODS: Retrospective observational case report and review of anterior tuberculous scleritis. RESULTS: A 28-year-old woman, previously diagnosed as presumed tubercular panuveitis, presented with necrotizing sclerokeratitis and progressed to develop panophthalmitis. Laboratory investigations revealed multidrug-resistant Mycobacterium tuberculosis as the etiological agent. We reviewed cases of anterior tuberculous scleritis published in the literature, with regards to clinical features, microbiological investigations, treatment, and outcomes. Treatment includes standard antitubercular therapy, with or without systemic corticosteroids. Poor response to treatment is seen either due to delayed diagnosis or drug resistance, and the significance of the same is highlighted in our case. CONCLUSION: Diagnosis of tuberculous scleritis is a challenge. Therapeutic failure must alert the clinician for drug resistance which is diagnosed early, can prevent the devastating outcomes.

Clinicopathological, Microbiological and Polymerase Chain Reaction Study in a Case of Nocardia Scleritis.

Purpose: To describe the clinicopathological, microbiological and polymerase chain reaction (PCR) study in a case of Nocardia scleritis.Methods: A retrospective chart review.Results: A 32-year old male presented with pain, redness and nodular scleral swelling in the left eye for the past two and a half months following an accidental rice powder injury. He was earlier diagnosed to have tubercular scleritis and treated with oral steroids and anti-tubercular therapy. A repeat scleral biopsy on histopathological examination showed granulomatous inflammation. Microbiological investigations revealed the growth of Gram +ve branching filamentous bacilli in culture suggestive of Nocardia sp. PCR based DNA sequencing identified the bacterium as Nocardia cyriacigeorgica. The patient responded to topical fortified amikacin (2.5%), fortified cefuroxime, oral sulfamethoxazole and trimethoprim with complete healing of scleritis.Conclusions: Nocardia scleritis can be a diagnostic challenge for clinicians. Newer molecular techniques along with histopathological and microbiological investigations can clinch the diagnosis.

Insect wing case: unusual foreign body.

PURPOSE: To report five cases of insect wing case foreign body. METHODS: Clinical presentation, investigations, management, and outcome of these cases are discussed. RESULTS: Five patients, four males and one female, in the age group from 4 to 55 years presented with an insect wing case embedded in the cornea or peripheral limbus. All patients were relatively asymptomatic, and the foreign body was associated with vascularization and infiltration. Culture of the foreign body after removal showed Staphylococcus epidermidis in two cases and Corynebacterium species and Mycobacterium fortuitum in one case each. All patients responded to removal of the wing case foreign body and treatment with topical ciprofloxacin (0.3%). CONCLUSION: Insect wing case is an unusual foreign body and produces minimal symptoms and may be associated with infective agents in some patients.

Polymerase chain reaction in the diagnosis of Aspergillus endophthalmitis.

BACKGROUND & OBJECTIVES: Aspergillus endophthalmitis is the commonest type of vision threatening fungal endophthalmitis encountered in India. Since conventional methods lack sensitivity, we evaluated polymerase chain reaction (PCR) against the conventional mycological methods in the diagnosis of Aspergillus endophthalmitis. METHODS: Twenty-seven intraocular specimens from 22 patients with suspected fungal endophthalmitis (proven as non-bacterial origin) and 10 patients with non-infective intraocular disorders (controls) were tested. The intraocular specimens from these patients were subjected to the conventional methods, viz., microscopy and culture for growth of fungi, as well as PCR for the detection and differentiation of species of Aspergillus. RESULTS: None of the controls were positive by microscopy, culture or PCR. Among the 27 test samples, 4 were positive by culture for Aspergillus species, these were also positive by PCR. In addition, PCR detected and identified Aspergillus species in 2 culture negative specimens. The average time required for culture and identification of Aspergillus was 10 days, whereas PCR needed only 24 h. INTERPRETATION & CONCLUSION: This study indicates that PCR was not only a more sensitive, but also a rapid diagnostic tool compared to the conventional mycological methods in the diagnosis of Aspergillus endophthalmitis.

Use of polymerase chain reaction (PCR) and DNA probe hybridization to determine the Gram reaction of the infecting bacterium in the intraocular fluids of patients with endophthalmitis.

OBJECTIVES: To evaluate polymerase chain reaction (PCR) combined with DNA probe hybridization to determine the Gram reaction of the bacterium in intraocular specimens from patients with infectious endophthalmitis. METHODS: Fifty-seven intraocular specimens - 17 aqueous humor (AH) and 40 vitreous fluid (VF) - from 55 patients with clinically diagnosed infectious endophthalmitis and 25 control intraocular specimens from non-infectious ocular disorders (10 AH and 15 VF) were evaluated by microscopy, culture and PCR-DNA probe hybridization to detect the Gram reaction of the bacterium. RESULTS: PCR-DNA probe hybridization was specific and sensitive to detect 30 fg of both gram-positive and gram-negative bacterial DNA. None of the controls showed bacteria by microscopy, culture or PCR. Of the 57 intraocular specimens, conventional microbiological methods could detect a bacterial aetiology in 32 (56.1%), while PCR-DNA probe hybridization could detect 52 (91.2%) specimens. This difference was statistically significant (P= 0.003). In bacteriologically positive specimens, there was absolute correlation of the Gram reaction between the results of smear and culture methods and PCR-DNA probe hybridization. Of the 25 bacteriologically negative specimens, 20 (80%) were positive by PCR-DNA probe hybridization, of which seven (35%) were gram-positive, 12 (60%) gram-negative and one (5%) positive by both. Results of PCR on AH and VF were not significantly different. CONCLUSION: PCR and DNA probe hybridization to determine the Gram reaction of the bacterium in intraocular fluids is a specific and sensitive method in the diagnosis of bacterial endophthalmitis. AH is an ideal specimen for PCR, since its collection is a simple and safe office procedure.

Spectrum of aetiological agents of postoperative endophthalmitis and antibiotic susceptibility of bacterial isolates.

PURPOSE: To determine the spectrum of infectious agents of postoperative endophthalmitis, the relationship with the time of onset of symptoms after surgery and the antibiotic susceptibilities of the aerobic bacterial isolates. METHODS: A retrospective review of microbiological records from January 1995 to December 1998 yielded 173 isolates from intraocular specimen of 170 patients with culture-proven postoperative endophthalmitis. Antibiotic susceptibility of these isolates was determined for various ocular antibiotics using the Kirby-Bauer disk-diffusion test. Based on the time of onset of illness, clinical presentation was classified into acute, delayed and chronic. RESULTS: Among 170 cases, 71 (41.7%) were attributable to gram-negative, 64 (37.6%) to gram-positive bacteria, and 37 (21.8%) to fungi. Gram-negative bacteria included P. aeruginosa (29;17.1%), other Pseudomonas spp (15;8.8%), non-fermenters (18;10.6%) and others (10;5.8%). Among these, 40 of 72 (55.5%) were sensitive to gentamicin, 47 of 72 (65.2%) to cefotaxime, 47 of 69 (68.1%) to amikacin, 52 of 71 (73.2%) to ciprofloxacin, and 25 of 40 (62.5%) to ceftazidime. The gram-positive bacteria included S. epidermidis (22;12.9%), S. aureus (13;7.6%), P. acnes (10;5.9%), Enterococcus spp (4;2.3%), Streptococcus spp (7;4.1%) and others (8;4.8%). Among these, 41 of 53 (77.3%) were sensitive to gentamicin, 47 of 53 (88.6%) to cefotaxime, 46 of 52 (88.4%) to ciprofloxacin, 38 of 41 (92.6%) to cefazolin and 27 of 37 (72.9%) to ceftazidime. All gram-positive bacteria were sensitive to vancomycin. CONCLUSION: In this large series of postoperative endophthalmitis, gram-negative bacilli followed by fungi accounted for the largest number of cases. A high degree of resistance of gram-negative bacilli to gentamicin, cefotaxime, amikacin and ceftazidime was recorded.

Detection of herpes simplex virus (HSV) genome using polymerase chain reaction (PCR) in clinical samples comparison of PCR with standard laboratory methods for the detection of HSV.

BACKGROUND: Diagnosis of Herpes simplex virus (HSV) infections is achieved by detecting the antigen and isolating the virus from the specimen, which requires 7-28 days. With the recently introduced molecular biological technique of polymerase chain reaction (PCR), the diagnosis of HSV infections has been made more rapid and specific. OBJECTIVE: We evaluated PCR in comparison with the standard laboratory methods on different types of clinical specimens referred to in our laboratory. STUDY DESIGN: A total of 54 specimens, from 54 patients, were investigated. Antigen detection on direct smears was carried out using fluorescent antibody test (FAT) and virus isolation was performed using conventional tube culture method. PCR was carried out with the DNA extracted from various specimens using primers, which coded for the DNA polymerase gene giving a 179 base pair (bp) product. RESULTS: The primers were specific for HSV-1 and HSV-2, and the sensitivity of the primers was found to be 0.5 and 0.2 fg in the detection of HSV-1 and HSV-2 DNA, respectively. Of the 50 specimens (excluding 4 archival formalin fixed tissue specimens, which were not subjected to virological methods of detection) HSV was detected by virological methods and PCR in nine specimens, and by PCR alone in 15 additional specimens, thus increasing the analytical sensitivity significantly by 30% (McNemar test: P = 0.0001). The positivity of PCR in all nine virologically positive specimens and the 4 archival specimens obtained from proven lesions of HSV infections further confirmed the specificity of the PCR. CONCLUSION: PCR, in our study, was found to be a rapid, specific and highly sensitive method for the detection of HSV in clinical specimens.

Polymerase chain reaction in the diagnosis of bacterial endophthalmitis.

BACKGROUND: Microbiological investigations of vitreous fluid (VF) and aqueous humour (AH) specimens have often failed to detect the infecting agent in infectious endophthalmitis, resulting in a clinical dilemma regarding therapy. In this study, the polymerase chain reaction (PCR) was evaluated in the diagnosis of bacterial and Propionibacterium acnes endophthalmitis. METHODS: 58 intraocular specimens (30 VF and 28 AH) from 55 cases of endophthalmitis and 20 specimens (14 VF and 6 AH) as controls from non-infective disorders were processed for microbiological investigations. Nested PCR directed at the 16S rDNA using universal primers for eubacterial genome was done. PCR for P acnes was performed on specimens microbiologically negative by conventional techniques but eubacterial genome positive. RESULTS: Of the 20 controls from non-infective cases, one (5%) was positive using eubacterial primers and none with P acnes primers. PCR for eubacterial genome showed 100% correlation with 20 (34.5%) bacteriologically positive specimens. Eubacterial genome, was detected in 17 (44.7%) of 38 bacteriologically negative specimens and nine (52.9%) out of the 17 were positive for P acnes genome. Among the 21 eubacterial PCR negative specimens, seven were fungus positive. By inclusion of PCR, microbiologically positive specimens increased from 46.5% to 75.8%. PCR on AH was as sensitive as that on VF for the detection of both eubacterial and the P acnes genome. CONCLUSION: PCR performed on AH and VF is a reliable tool for the diagnosis of bacterial and P acnes endophthalmitis particularly in smear and culture negative specimens.

Significance of mycobacterial immune complexes (IgG) in the diagnosis of tuberculous meningitis.

SETTING: Tuberculous meningitis (TBM) has high mortality, especially in children. Early accurate diagnosis and adequate treatment would reduce this mortality. Diagnosis of TBM remains an enigma because of low cerebrospinal fluid (CSF) culture positivity for Mycobacterium tuberculosis and weak clinical correlation with conventional immunoassays. OBJECTIVE: To evaluate significance of mycobacterial immune complexes (IgG) and anti-mycobacterial antibodies in the diagnosis of TBM. METHOD: CSF from TBM patients and various types of other neurological (both infectious and non-infectious) and non-neurological cases was studied for the presence of IgG and anti-mycobacterial antibodies using antigen capture (by anti-BCG) and multilayered ELISA (using M. tuberculosis soluble extract), respectively. RESULTS: IgG in CSF could be detected in 33 of 55 (60%) and anti-mycobacterial antibodies in 30 of 55 (55%) TBM cases. Presence of IgG, anti-mycobacterial antibodies or both could be detected in 45 of 55 (82%) of the TBM cases. Excepting three of the pyogenic meningitis CSF, none of the infectious (49), non-infectious neurological cases (30) and non-neurological controls (32) showed the presence of IgG or anti-mycobacterial antibodies. CONCLUSION: Detection of IgG along with anti-mycobacterial antibodies aids in diagnosis of a large proportion of TBM cases.