Sequelae of microsporidial keratoconjunctivitis and its management

Biomarker Detection and Validation for Corneal Involvement in Patients With Acute Infectious Conjunctivitis

Importance

Infectious conjunctivitis can lead to corneal involvement and result in ocular morbidity. The identification of biomarkers associated with corneal involvement has the potential to improve patient care.

Objective

To identify biomarkers in patients with acute infectious conjunctivitis.

Design, Setting, and Participants

This cross-sectional study took place from December 2016 to March 2024. Analyses were performed in 3 phases. First, logistic regression and machine learning algorithms were used to predict the probability of demonstrating corneal involvement in patients with presumed infectious conjunctivitis. Second, quantitative reverse transcription polymerase chain reaction (RT-qPCR) was used to confirm the most important biomarker gene identified by the algorithm. Third, the biomarker gene was validated in prospectively collected conjunctival samples of adult patients from 3 outpatient centers in Thailand and 1 in India. Patients with signs and symptoms of infectious conjunctivitis and onset within less than 14 days were eligible. Exclusion criteria were the inability to consent, presumed toxicity, or allergic conjunctivitis.

Exposures

Acute infectious conjunctivitis.

Main Outcomes and Measures

The identification and validation of ocular surface gene expression associated with corneal findings on slitlamp examination.

Results

Thirteen genes exhibited a 1.5-log2 fold change in expression in patients with corneal involvement compared to patients without corneal involvement. Using the 13 genes to train and cross validate, logistic regression produced the highest mean area under the receiver operating characteristic curve (AUROC; 0.85; 95% CI, 0.84-0.86) for corneal involvement. The removal of apolipoprotein E (APOE) from the gene ensemble led to a decline in predictive performance of the logistic regression classifier (from mean AUROC 0.85 [95% CI, 0.84-0.86] to 0.74 [95% CI, 0.73-0.75]; adjusted P = .001 [Tukey test]). Orthogonal testing of APOE expression level with RT-qPCR showed that APOE expression was higher in patients with corneal involvement compared to patients without (median [IQR], 0.23 [0.04-0.47] vs 0.04 [0.02-0.06]; P = .004 [Mann-Whitney U test]). Using a Youden index of 0.23 Δ threshold cycle, APOE had a sensitivity of 56% (95% CI, 33-77) and a specificity of 88% (95% CI, 79-93) in 106 samples with conjunctivitis at Aravind, India (P < .001 [Fisher exact test]). When applied to a different patient population in Thailand, the same criteria could discriminate between disease states (58 samples; sensitivity, 47%; 95% CI, 30-64 and specificity, 93%; 95% CI, 77-99; P = .001 [Fisher exact test]).

Conclusions and Relevance

The results from this study suggest that the host conjunctival immune response can be meaningfully interrogated to identify biomarkers for ocular surface diseases.

Intravesical liposomal tacrolimus for hemorrhagic cystitis: a phase 2a multicenter dose-escalation study

BACKGROUND

Hemorrhagic cystitis (HC) is an inflammatory disease of the bladder with sustained hematuria for which there is currently no approved drug treatment. We evaluated a liposomal tacrolimus preparation (LP-10) in patients with refractory moderate to severe sterile HC.

METHODS

This phase 2a dose-escalation study assessed the safety and efficacy of up to 2 intravesical instillations of LP-10 (2, 4, or 8 mg tacrolimus) in 13 patients with HC. Primary efficacy outcomes were changes from baseline in the number of bleeding sites on cystoscopy, microscopic urine analysis for red blood cells (RBCs), and hematuria on dipstick. Additional efficacy measures included urinary incontinence, frequency, and urgency on a 3-day diary and cystoscopy global response assessment (GRA). Blood samples for pharmacokinetic (PK) assessment were obtained in all patients.

RESULTS

Intravesical LP-10 was well tolerated, with no treatment-related severe or serious adverse events (AEs) and only 3 drug-related AEs (artificial urinary sphincter malfunction, dysuria, and bladder spasms). LP-10 blood levels showed short durations of minimal systemic uptake. Treatment resulted in significant improvements in bleeding on cystoscopy, RBC counts in urine, hematuria on dipstick, and urinary incontinence. Bleeding on cystoscopy and urinary incontinence showed dose-dependent improvements that were more pronounced in the 4 mg and 8 mg dose groups. All dose groups showed a significant improvement in cystoscopy GRA.

CONCLUSION

LP-10 was well tolerated, with clinically relevant efficacy seen in improvements in cystoscopic bleeding, hematuria, and urinary incontinence. The benefit-risk profile supports the further clinical development of LP-10 at a tacrolimus dose of 4 mg.

Microsporidial keratoconjunctivitis - first outbreak in Japan

BACKGROUND

Most cases of microsporidial keratoconjunctivitis are found in the Southern hemisphere. Our purpose was to investigate the first outbreak of microsporidial keratoconjunctivitis in Japan among healthy, immunocompetent soccer players from the same team during a 1-month period.

CASE PRESENTATION

This study is an observational case series. The medical records were analyzed for five cases with microsporidial keratoconjunctivitis who presented within September 2022. All five cases were males between 28 and 36 years old. These previously healthy individuals belonged to the same football team. Their eyes were considered susceptible to contaminated water or dirt from the turf at game and practice sites. All cases involved unilateral conjunctivitis, with scattered round white lesions that showed positive fluorescein staining in the corneal epithelium. All cases experienced diminution of vision in the affected eye. In three cases, direct smears showed spores of approximately 2-3 μm in diameter. Polymerase chain reaction (PCR) analysis of corneal scrapes revealed partial amplification of microsporidial 18 S ribosomal RNA gene in four cases. Sequences of PCR products from all four cases showed 100% identity with strains of Vittaforma corneae previously reported from an outbreak in Singapore. All cases were treated with topical therapy, including voriconazole, fluorometholone, and levofloxacin. Four eyes underwent corneal scraping. After treatment, all eyes healed without residual opacities.

CONCLUSIONS

Only a few sporadic case reports of this disease have previously been reported in Japan. We detected V. corneae in our case series, representing what appears to be the first outbreak of microsporidial keratoconjunctivitis in Japan. Exposure to contaminated water or soil, in addition to inadequate sanitary facilities, represents a potential source of infection. Further investigations to clarify the characteristics of microsporidia seem warranted.

Microsporidia-Associated Anterior Uveitis After Keratoconjunctivitis

OBJECTIVE

The aim of this study was to describe the clinical features and management of uveitis associated with microsporidial keratoconjunctivitis (MKC).

METHODS

The medical records of clinically diagnosed or microbiologically proven patients with MKC between July 2016 and August 2021 were reviewed. Patients with documented evidence of keratic precipitates (KPs) or anterior chamber cells were analyzed for their demography, clinical features, and treatment. Patients with microsporidial stromal keratitis and herpes simplex virus keratouveitis were excluded from the study.

RESULTS

Of the 2212 patients reviewed within the study period 171 of 172 eyes (7.7%) had documented evidence of KPs and/or anterior chamber cells. The patients' mean age was 43.8 ± 13.8 years, and there were more men (n = 120). The mean duration of appearance of KPs was 6.9 ± 5.5 days, and 28% (n = 48 of 171) appeared on the day of presentation. Superficial punctate keratitis was central and diffuse in 48 and 49 patients, respectively. The treatment was either lubricant alone (45.3%; 78 eyes) or combined with topical steroids (54.7%; 94 eyes). The mean duration of the resolution was longer in the "corticosteroid" than "no corticosteroid" group: KPs: 15.3 ± 6.5 days versus 12.3 ± 5.8 days ( P = 0.007) and superficial punctate keratitises: 15.4 ± 9.4 days versus 11.7 ± 6.2 days ( P = 0.01). The presenting visual acuity with a pinhole was 0.26 ± 0.26 (logMAR) and it improved to 0.03 ± 0.07 on resolution ( P < 0.0001, paired t test).

CONCLUSIONS

Uveitis after MKC is a self-limiting entity that often resolves without corticosteroid. One must exercise caution in using steroids in the presence of active corneal lesions.

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.

Microsporidial Keratitis Related to Water Exposure: A Case Series

The objective of this retrospective study was to present a series of cases involving the rare ocular disease of microsporidia keratitis treated at a private practice clinic and describe the details regarding specific water exposure, clinical course, voriconazole treatment, and increased prevalence of this infection in Augusta, Georgia, USA. Our analysis was based on the accumulated data from all patients (n=15) diagnosed with microsporidia keratitis at our private practice clinic; the clinical course of three cases is discussed in detail in this article. Specific environmental exposures were documented in 10 patients. All patients self-reported that they had no acquired immunodeficiency. In all cases, patients had complete resolution of active symptoms after receiving treatment with 1-2% topical voriconazole, with an approximate average primary treatment duration of 40.1 ± 17.1 days (median: 40 days, range: 14-70 days). None of the patients reported any clinically significant adverse effects from therapy.

There have been increasing reports about this emerging infectious pathogen, particularly in Asia. However, there is limited data in the literature on the etiology, pathogenesis, and treatment of microsporidia-caused ophthalmic diseases. In this case series, we highlight the strong correlation of our patients' condition with specific types of water exposure in the USA as well as the complete resolution of active disease in all our patients as a result of monotherapy with topical voriconazole.

"A prospective study on the clinical course and proposed morphological classification scheme of microsporidial keratoconjunctivitis."

Background and objective: To describe the clinical course and propose a morphological classification scheme of microsporidial keratoconjunctivitis. Methods: This is a prospective study at L V Prasad Eye Institute, Odisha, between August-January (2017-19). Patients of any age or sex, microbiologically proven as microsporidial keratoconjunctivitis were included. Demographic parameters, history, clinical course, and visual outcome were analysed. All received artificial tear substitutes till resolution and topical immunosuppressants used in cases of persisting sub-epithelial infiltrates (SEI) beyond 2 weeks. Results: Fifty-three eyes of 47 cases were included with males, 72.3%. Corneal lesions were classified into 3 morphological types- coarse, ring, and flat-topped (Type1, 2 & 3). Depending upon the location, Type 1 was further sub-divided into peripheral, paracentral, central, and diffuse (Type 1a, b, c & d). The mean age was highest in Type 3(p = .026). Risk factors and prior steroid use were most common in Type 1d. The mean duration of symptom before presentation was longest in Type 3(11.6 ± 3.65) days. Severe conjunctival congestion at presentation in more than half of the eyes were seen in Type 1a, 1b and 1d, with moderate congestion at Day14 persisting in 66.7% and 40% of eyes belonging to Type 1c and 1d, respectively. Keratic precipitates were most common in Type 2. The mean duration of resolution was longest in Type 1d (38 ± 15.87) days and shortest in type 1b (7.88 ± 2.47) days (p = .022). Persistent SEIs beyond Day 90 were seen in total of 6 (11.3%) (Type 1c & 1d- 3 each) eyes and recurrent SEIs in 7(13.2%) (Type 1c-2 & 1d- 5) eyes. The mean duration of topical steroids use was longest in Type 1d (49.3 ± 22.3) days, followed by Type 1c (28 ± 0) days. Conclusion: Microsporidial keratoconjunctivitis can have a variable clinical presentation, the course of each being different depending on the host and ocular surface factors. Though considered as a self-limiting disease, central and diffuse coarse variety (Type1c&1d) required long-term topical immunosuppressants and follow-up.