Post-Keratoplasty Microbial Keratitis in the Era of Lamellar Transplants-A Comprehensive Review

Microbial keratitis in a post-transplant cornea should be considered a distinct entity from microbial keratitis in a non-transplant cornea. Firstly, the use of immunosuppressive treatments and sutures in corneal transplants changes the etiology of keratitis. Secondly, corneal transplant has an impact on corneal biomechanics and structure, which facilitates the spread of infection. Finally, the emergence of lamellar transplants has introduced a new form of keratitis known as interface keratitis. Given these factors, there is a clear need to update our understanding of and management strategies for microbial keratitis following corneal transplantation, especially in the era of lamellar transplants. To address this, a comprehensive review is provided, covering the incidence, risk factors, causes, and timing of microbial keratitis, as well as both clinical and surgical management approaches for its treatment in cases of penetrating and lamellar corneal transplants.

Utilization of the Reinstein ICL Sizing Formula With Hand-held Ultrasound Biomicroscopy Measurements

PURPOSE

To evaluate the accuracy of the Reinstein formula with hand-held ultrasound biomicroscopy (UBM) measurements for sizing of the Implantable Collamer Lens (ICL).

METHODS

A total of 107 myopic eyes of 57 patients implanted with the ICL were included in the study. The size of the ICL was selected based on the manufacturer's recommendations. Agreement between the vault predicted by the Reinstein formula and the vault measured postoperatively was analyzed with Bland-Altman plots.

RESULTS

A total of 95% and 81% of patients had a postoperative vault ranging from 150 to 1,000 and 250 to 750 μm, respectively. The mean vault predicted by the Reinstein formula and the postoperative vault in the current study were 580 ± 181 and 547 ± 200 μm, respectively. The size recommendations of the Reinstein formula and the formula provided by the manufacturer, the Kojima formula, and the Dougherty formula overlapped in 50%, 57%, and 49% of eyes, respectively.

CONCLUSIONS

The results show that the Reinstein formula combined with a hand-held UBM provides reliable sizing predictions of the ICL. However, considering that robotic UBM measurements have demonstrated a narrower range of deviation in predicting vault depth in previous studies, a direct comparison study between robotic UBM and hand-held UBM measurements is necessary to fully assess the limitations of combining hand-held UBM with the Reinstein formula. [J Refract Surg. 2024;40(3):e142-e147.].

Impact of First Healthcare Provider on Acanthamoeba Keratitis Course: How to Overcome Poor Prognosis in Acanthamoeba Keratitis Treatment? A Single Tertiary Center, Observational Study

Background

To assess the difference in course and final visual outcome of Acanthamoeba keratitis (AK) patients based on the first healthcare provider (HCP) seen.

Methods

Retrospective observational cohort study of AK patients admitted to the Manchester Royal Eye Hospital between 2003 and 2017. HCPs were grouped (Group 1: Optometrists, Opticians; Group 2: General Practitioners (GPs); Group 3: Ophthalmologists) and the data analyzed on demographics, risk factors, clinical history, clinical features, and Acanthamoeba subspecies.

Results

Forty-one patients with unilateral culture-proven AK were included. Median time to consultation with first HCP was 7 days (IQR 4-14 days), while mean time to the correct diagnosis of AK was 15 days (IQR 7-29 days). Patients saw an optician, optometrist or ophthalmologists significantly earlier than GPs (median 4 days, vs 15 or 5 days, respectively, p = 0.04). Bacterial keratitis was the most common initial clinical diagnosis (43%). The shortest time to making the AK diagnosis (median 11 days) and the highest rate of initiating AK treatment started at the first visit (38%) were both in the ophthalmologists' group. No significant differences were observed in initial and final visual acuity between HCP groups (p = 0.36).

Conclusion

AK patients often seek ocular help earlier from optometrists and opticians than medical doctors. Final clinical outcomes did not significantly differ based on the first HCP seen, but ophthalmologists were more likely to make the diagnosis of AK and initiate anti-amoebal therapy faster than other HCPs. Greater education and collaboration between ophthalmologists and other HCPs to increase awareness of AK are needed.

Corneal ring infiltrate- far more than Acanthamoeba keratitis: review of pathophysiology, morphology, differential diagnosis and management

OBJECTIVE

Ring infiltrates usually accompany numerous infectious and sterile ocular disorders. Nevertheless, systemic conditions, drugs toxicity and contact lens wear may present with corneal ring infiltrate in substantial part. Considering its detrimental effect on vision, detailed knowledge on etiology, pathophysiology, differential diagnosis, and management should be considered essential for every ophthalmologist.

METHODS

The PUBMED database was searched for "corneal ring infiltrate" and "ring infiltrate" phrases, "sterile corneal infiltrate" and "corneal infiltrate". We analyzed articles written in English on risk factors, pathophysiology, clinical manifestation, morphological features, ancillary tests (anterior-segment optical coherence tomography, corneal scraping, in vivo confocal microscopy), differential diagnosis and management of corneal ring infiltrate.

RESULTS

Available literature depicts multifactorial origin of corneal ring infiltrate. Dual immunological pathophysiology, involving both antibodies-dependent and -independent complement activation, is underlined. Furthermore, we found that the worldwide most prevalent among non-infectious and infectious ring infiltrates are ring infiltrates related to contact-lens wear and bacterial keratitis respectively. Despite low incidence of Acanthamoeba keratitis, it manifests with corneal ring infiltrate with the highest proportion of the affected patients (one third). However, similar ring infiltrate might appear as a first sign of general diseases manifestation and require targeted treatment. Every corneal ring infiltrate with compromised epithelium should be scraped and treat as an infectious infiltrate until not proven otherwise. Of note, microbiological ulcer might also lead to immunological ring and therefore require anti-inflammatory treatment.

CONCLUSION

Corneal ring infiltrate might be triggered not only by ocular infectious and non-infectious factors, but also by systemic conditions. Clinical assessment is crucial for empirical diagnosis. Furthermore, treatment is targeted towards the underlying condition but should begin with anti-infectious regimen until not proven otherwise.

Effect of COVID-19 Lockdowns on Eye Emergency Department, Increasing Prevalence of Uveitis and Optic Neuritis in the COVID-19 Era

Background: The COVID-19 pandemic led to the reorganization of the health care system. A decline in health- and life-saving procedures has been reported in various medical specialties. However, data on ophthalmic emergencies during lockdowns is limited. Methods: We conducted a retrospective, observational, case-control study of 2351 patients registered at the ophthalmic emergency department of a tertiary hospital in Poland during three national COVID-19 lockdowns (March/April 2020, November 2020, and March/April 2021) and corresponding months in 2019. Results: The total number of visits declined from a mean of 720/month in the non-COVID era to 304/month during COVID-19 lockdowns (p < 0.001). Ocular trauma incidence dropped significantly from 2019 (non-COVID months) to 2020/2021 (COVID group mean 201 vs. 97 patients monthly, respectively, p = 0.03). Of note, the percentage of foreign bodies removal was significantly higher during lockdowns than corresponding time in the non-COVID era. A downward trend for vitreous detachment and macular disorders cases was observed between COVID and non-COVID time. Uveitis and optic neuritis patients were seen more often during lockdowns (p < 0.001 and p = 0.0013, respectively). In contrast, the frequency of conjunctivitis and keratitis, potentially COVID-related problems, decreased significantly in COVID-19 time (mean 138 vs. 23 per month in non-COVID vs. COVID lockdowns, respectively, p < 0.001). Conclusions: The overall number of eye emergency visits declined during COVID-19 lockdowns. Conjunctivitis and keratitis rates dropped during the lockdowns. Interestingly, the frequency of immune-mediated ocular conditions (uveitis, optic neuritis) increased significantly which might be triggered by SARS-CoV2 infection.

Clinical and laboratory parameters by age for patients diagnosed with multiple sclerosis between 2000 and 2015

AIM OF THE STUDY

To compare the demographic, clinical and laboratory characteristics of patients with multiple sclerosis (MS) analysed based on the age at which they were diagnosed.

CLINICAL RATIONALE FOR THE STUDY

Most cases of MS are diagnosed between the ages of 20 and 40 years, but the clinical characteristics of patients with MS over this age range have rarely been studied.

MATERIAL AND METHODS

182 patients diagnosed with MS between 2000 and 2015 were divided into four groups by age at diagnosis: < 30 years (n = 62), 30-39 years (n = 54), 40-49 years (n = 27), and ≥ 50 years (n = 39). The demographic, clinical and laboratory features of each age group were investigated and between-groups comparisons analysed.

RESULTS

There were no significant differences in the female-to-male ratio between groups, which was close to 3:1 in every group (p = 0.98). Motor symptoms were more common as the first manifestation of MS with increasing age (< 30: 19.3%; 30-39: 37.0%; 40-49: 44.4%; ≥ 50: 61.5%). Visual and sensory symptoms were responsible for nearly half of first manifestations in patients < 30 to 49, but affected a significantly lower proportion of patients in the oldest group (p = 0.01). Median (interquartile range [IQR]) Expanded Disability Status Scale at diagnosis was higher with advancing age (2 [1.5-3], 2.25 [1.5-3.5], 3 [2-3.5], and 3.5 [3-5]; p < 0.01). There was also a higher proportion of patients with progressive forms of the disease with age, especially primary progressive MS (0.0%, 3.7%, 14.8%, and 51.3%; p < 0.01). The median (IQR) time needed to confirm the diagnosis of MS became significantly longer as age increased (7 [2-25], 9 [2-32], 12 [6-58], and 26 [12-60] months; p < 0.01). In laboratory tests, significant differences were found only in the rate of post-contrast enhancement by magnetic resonance imaging, which was lower in the older age groups (63.2%, 50.0%, 31.6%, and 30.0%; p < 0.01).

CONCLUSIONS AND CLINICAL IMPLICATIONS

Our study indicates significant differences in the demographic and clinical picture of MS depending on the age of the patient at diagnosis. Diagnostic delay in older patients is a common problem, and this study shows the features of later forms of MS to help inform neurologists and improve time to diagnosis.

Demographic and clinical profile of patients with multiple sclerosis diagnosed over the last 30 years according to different diagnostic criteria

The aim of this study was to investigate the demographic and clinical characteristics of patients with multiple sclerosis (MS) diagnosed between 1986 and 2015. 333 patients with definite MS were divided into four subgroups according to the following diagnostic criteria: Group A) Poser (n = 145), Group B) McDonald 2000 (n = 66), Group C) McDonald 2005 (n = 62), and Group D) McDonald 2010 (n = 60). We investigated: 1) patient sex and age at diagnosis, 2) symptoms and number of relapses that prompted MS diagnosis, 3) time between first symptoms suggestive of MS and confirmed diagnosis, and 5) Expanded Disability Status Scale (EDSS) score at disease onset. The overall female-to-male ratio was 2.3:1, but in the subgroups it differed significantly (A - 1.9; B - 1.6; C - 4.7; D - 3.6). The mean age at diagnosis (in years) decreased from 39.6 ± 13.3 in Group A to 29.9 ± 9.3 in Group D, p < 0.001. Pyramidal signs remained the most common manifestation regardless of the diagnostic criteria, although an increased trend of visual dysfunction was observed (A - 16%, B - 14%, C - 19%, D - 23,3%; A vs D, p < 0.001). The number of relapses before diagnosis decreased from median 4.0 to 2.5 in Group A and Group D, p < 0.001. Time from the first symptom to diagnosis shortened from 88.9 ± 80.2 months (Group A) to 33.6 ± 68.2 months (Group D), p < 0.0001. Mean EDSS score at diagnosis also decreased: A - 4.4 ± 2.3; B - 3.1 ± 1.7; C - 2.7 ± 1.3; D - 2.8 ± 1.4, p < 0.001. Our study indicates significant differences in demographic and clinical characteristics of MS diagnosed according to the changing criteria.

Ex vivo anti-microbial efficacy of various formaldehyde releasers against antibiotic resistant and antibiotic sensitive microorganisms involved in infectious keratitis

BACKGROUND

Corneal infections with antibiotic-resistant microorganisms are an increasingly difficult management challenge and chemically or photochemically cross-linking the cornea for therapy presents a unique approach to managing such infections since both direct microbial pathogens killing and matrix stabilization can occur simultaneously. The present study was undertaken in order to compare the anti-microbial efficacy, in vitro, of 5 candidate cross-linking solutions against 5 different microbial pathogens with relevance to infectious keratitis.

METHODS

In vitro bactericidal efficacy studies were carried out using 5 different FARs [diazolidinyl urea (DAU), 1,3-bis(hydroxymethyl)-5,5-dimethylimidazolidine-2,4-dione (DMDM), sodium hydroxymethylglycinate (SMG), 2-(hydroxymethyl)-2-nitro-1,3-propanediol (NT = nitrotriol), 2-nitro-1-propanol (NP)] against 5 different microbial pathogens including two antibiotic-resistant species [methicillin-sensitive Staphylococcus aureus (MSSA), methicillin-resistant Staphylococcus aureus (MRSA), vancomycin-resistant Enterococcus (VRE), Pseudomonas aeruginosa (PA), and Candida albicans (CA)]. Standard in vitro antimicrobial testing methods were used.

RESULTS

The results for MSSA were similar to those for MRSA. DAU, DMDM, and SMG all showed effectiveness with greater effects generally observed with longer incubation times and higher concentrations. Against MRSA, 40 mM SMG at 120 min showed a > 95% kill rate, p < 0.02. Against VRE, 40 mM DAU for 120 min showed a > 94% kill rate, p < 0.001. All FARs showed bactericidal effect against Pseudomonas aeruginosa, making PA the most susceptible of the strains tested. Candida showed relative resistance to these compounds, requiring high concentrations (100 mM) to achieve kill rates greater than 50%.

CONCLUSION

Our results show that each FAR compound has different effects against different cultures. Our antimicrobial armamentarium could potentially be broadened by DAU, DMDM, SMG and other FARs for antibiotic-resistant keratitis. Further testing in live animal models are indicated.