Climatic influence on conjunctival bacteria of patients undergoing cataract surgery

Ocular Bacterial Infections: A Ten-Year Survey and Review of Causative Organisms Based on the Oklahoma Experience

Ocular infections can be medical emergencies that result in permanent visual impairment or blindness and loss of quality of life. Bacteria are a major cause of ocular infections. Effective treatment of ocular infections requires knowledge of which bacteria are the likely cause of the infection. This survey of ocular bacterial isolates and review of ocular pathogens is based on a survey of a collection of isolates banked over a ten-year span at the Dean McGee Eye Institute in Oklahoma. These findings illustrate the diversity of bacteria isolated from the eye, ranging from common species to rare and unique species. At all sampled sites, staphylococci were the predominant bacteria isolated. Pseudomonads were the most common Gram-negative bacterial isolate, except in vitreous, where Serratia was the most common Gram-negative bacterial isolate. Here, we discuss the range of ocular infections that these species have been documented to cause and treatment options for these infections. Although a highly diverse spectrum of species has been isolated from the eye, the majority of infections are caused by Gram-positive species, and in most infections, empiric treatments are effective.

Bacterial isolates and antimicrobial susceptibility pattern of ocular infection at a tertiary referral hospital in the South of Italy

PURPOSE

The present study aimed to determine the prevalence of bacterial and fungal infections of the eye and also to assess the antibiotic susceptibility pattern of bacterial isolates at a tertiary referral eye care hospital in Bari, Italy.

METHODS

Two hundred seventy three samples collected during a 2-year observation period. Culture, Gram's stain, potassium hydroxide mount and occasionally Giemsa staining was done for the clinical specimens. Antibiotic susceptibility testing was performed for bacterial growth.

RESULTS

Out of 273 samples processed, 236 (86.4%) yielded growth: of them, 183 (77,5%) were bacterial, 26 (11%) fungal, and 23 (9,7%) specimens showed the presence of Acanthamoeba. Among bacterial infections, 99 (54.5%) bacterial isolates were Gram-positives, and 82 (44.8%) were Gram-negatives. Among Gram positives, Tigecycline showed the greatest susceptibility (93.8%), followed by Linezolid (97%) and Daptomycin (95.18%). Gram negative bacteria strains were susceptible to Imipenem (95%), Meropenem (98,5%) and Amikacin (91%) Multidrug in vitro resistance (resistance >3 classes of antibiotics) was found in 45 Gram positive (63%). and 33 Gram negative (44%).

CONCLUSION

Conjunctival specimens yielded mainly bacterial growth with Staphylococcus species being the predominant isolate followed by Pseudomonas species. Findings from the current analysis evidence a substantial level of in vitro resistance to ≥3 antibiotics.

Bacteria and Dry Eye: A Narrative Review

(1) Background: Dry eye is a multifactorial disease of the ocular surface, the incidence of which has been increasing sharply. The pathogenesis of dry eye, especially in terms of the bacterial flora, has drawn great attention. Additionally, the potential treatment methods need to be explored. (2) Methods: We reviewed more than 100 studies and summarized them briefly in a review. (3) Results: We summarized the bacterial communities found on the ocular surface in the general population and patients with dry eye and found a relationship between dry eye and antibiotic therapy. We identified the possible mechanisms of bacteria in the development of dry eye by discussing factors such as the destruction of the antibacterial barrier, infectious diseases, microbiome homeostasis, inflammatory factors on the ocular surface and vitamin deficiency. (4) Conclusion: We systematically reviewed the recent studies to summarize the bacterial differences between patients with dry eye and the general population and brought up several possible mechanisms and possible treatment targets.

Bacteriological profile of conjunctiva bacterial Flora in Northeast China: a hospital-based study

PURPOSE

To investigate the distribution and influencing factors of preoperative conjunctival flora from patients undergoing penetrating ocular surgeries in northeast China.

METHODS

An observational and cross-sectional study design was used. In 305 eyes of 305 patients without infective eye diseases who underwent ocular surgeries at the First Affiliated Hospital of Harbin Medical University between May 2018 and May 2019, conjunctival sac scrapings were collected on the day before surgery.

RESULTS

The mean age of the participants was 60.73 ± 14.23 years, with the majority being female, married and unemployed with at least primary school education. The positive culture rate was 48.20% (147/305 eyes), and 191 bacterial strains were isolated; two or more strains were isolated from 22.45% (33/147) of positive samples. The most commonly isolated bacteria was Staphylococcus epidermidis (64.92%), surpassing Staphylococcus aureus (5.76%). The culture positive rate of the young (18-40 years) group was different between the females (26.67%) and males (69.23%) (P = 0.024), but in the middle-aged group and the elderly group, the rates between the sexes were similar, with an increasing trend. Patients who visited in summer or autumn presented a higher positive rate than other seasons. Hypertensive women had a higher rate than hypertensive men (58.14% vs. 40%, χ² = 5.8662, P = 0.0154).

CONCLUSIONS

In northeastern China, coagulase-negative Staphylococcus were the most common preoperative conjunctival bacteria. Hypertensive female patients, elderly patients, or those operated on in the summer and autumn should pay more attention to perioperative treatment.

TRIAL REGISTRATION

ChiCTR2100044659 .

Comparison of conjunctival microbiota of clinically normal Persian cats with and without nasolacrimal duct obstruction

OBJECTIVE

This study was performed to determine the conjunctival microbiota of Persian cats with and without nasolacrimal duct obstruction (NLDO).

ANIMALS STUDIED

Twenty-five Persian cats: 15 with bilateral NLDO (Group A) and 10 with no NLDO (Group B).

PROCEDURES

All fifty eyes were assessed. Sterile swab applicators were used for the collection of specimens, which were cultured. PCR was performed on conjunctival swab and blood samples for the detection of Mycoplasma spp. and feline herpesvirus 1(FHV-1), respectively.

RESULTS

FHV-1 was detected in two cats in Group A. Twelve eyes from Group A and four from Group B were Mycoplasma spp. positive based on the PCR results. Moreover, fungal culture was positive in six eyes from Group A and three eyes from Group B. The dominant fungus isolated was Aspergillus spp. (6 out of 11 fungal isolates). Other isolated fungi were Alternaria spp. and Cladosporidium spp. Twenty-three eyes had positive bacterial culture in Group A, while twelve eyes were positive in Group B. The most commonly isolated bacteria were Staphylococcus epidermidis (15 out of 38 bacterial isolates). β-hemolytic Streptococcus spp., Corynebacterium spp., and Staphylococcus aureus were isolated in similar proportions in both groups. Escherichia coli was also present in both groups.

CONCLUSIONS

Results of this study revealed same isolated fungal and bacterial spp. and in similar proportions in Persian cats with and without NLDO.

Association between the clinical and demographic characteristics of patients undergoing cataract surgery and their prevalence of conjunctival bacteria

PURPOSE

To identify characteristics of patients undergoing cataract surgery associated with pathogenic and antibiotic-resistant conjunctival bacteria.

SETTING

Spanish tertiary hospital.

DESIGN

Retrospective cross-sectional study.

METHODS

Records of consecutive patients undergoing cataract surgery between July 2005 and September 2014, contained data on patient characteristics and conjunctival bacteria systematically identified with preoperative tests and anesthetic evaluation. A multivariate logistic regression associated 12 bacterial groups with every category of 17 characteristics. Odds ratio (OR), 95% CIs expressed colonization risk.

RESULTS

In 14883 patients, categories associated with pathogenic bacteria were age older than 79 years with nonfermentative gram-negative bacilli (NFGNB) (OR 1.74, 1.12-2.71), enterococci (OR 1.90, 1.36-2.65), Enterobacteriaceae (OR 2.17, 1.65-2.87), and Staphylococcus aureus (OR 1.37, 1.16-1.62); obesity with S aureus (OR 1.52, 1.30-1.78), enterococci (OR 1.99, 1.47-2.68), and Enterobacteriaceae (OR 2.17, 1.70-2.77); dacryocystorhinostomy history with S aureus (OR 1.90, 1.48-2.44), Haemophilus spp. (OR 2.06, 1.37-3.11), Streptococcus pneumoniae (OR 3.14, 2.14-4.62), NFGNB (OR 2.23, 1.28-3.88), and enterococci (OR 1.80, 1.16-1.81); diabetes with S aureus (OR 1.27, 1.13-1.44), enterococci (OR 1.49, 1.19-1.87), and Enterobacteriaceae (OR 1.27, 1.04-1.54); smoking habit with Enterobacteriaceae (OR 2.11, 1.56-2.86); autumn with NFGNB (OR 2.0, 1.35-3.0); hot weather with S aureus (OR 1.23, 1.03-1.47); and lung, renal, and some heart insufficiencies with S aureus. Other staphylococci, highly antibiotic-resistant, were associated with old age, obesity, and hot weather.

CONCLUSIONS

Old age, obesity, diabetes, dacryocystorhinostomy history, smoking habit, and autumn and summer seasons increased the prevalence of enterococci, staphylococci, Enterobacteriaceae, and/or NFGNB. Obesity and humid-warm weather are key for choosing a cataract surgery prophylaxis.

Use of meteorological parameters for forecasting scarlet fever morbidity in Tianjin, Northern China

The scarlet fever incidence has increased drastically in recent years in China. However, the long-term relationship between climate variation and scarlet fever remains contradictory, and an early detection system is lacking. In this study, we aim to explore the potential long-term effects of variations in monthly climatic parameters on scarlet fever and to develop an early scarlet-fever detection tool. Data comprising monthly scarlet fever cases and monthly average climatic variables from 2004 to 2017 were retrieved from the Notifiable Infectious Disease Surveillance System and National Meteorological Science Center, respectively. We used a negative binomial multivariable regression to assess the long-term impacts of weather parameters on scarlet fever and then built a novel forecasting technique by integrating an autoregressive distributed lag (ARDL) method with a nonlinear autoregressive neural network (NARNN) based on the significant meteorological drivers. Scarlet fever was a seasonal disease that predominantly peaked in spring and winter. The regression results indicated that a 1 °C increment in the monthly average temperature and a 1-h increment in the monthly aggregate sunshine hours were associated with 17.578% (95% CI 7.674 to 28.393%) and 0.529% (95% CI 0.035 to 1.025%) increases in scarlet fever cases, respectively; a 1-hPa increase in the average atmospheric pressure at a 1-month lag was associated with 12.996% (95% CI 9.972 to 15.919%) decrements in scarlet fever cases. Based on the model evaluation criteria, the best-performing basic and combined approaches were ARDL(1,0,0,1) and ARDL(1,0,0,1)-NARNN(5, 22), respectively, and this hybrid approach comprised smaller performance measures in both the training and testing stages than those of the basic model. Climate variability has a significant long-term influence on scarlet fever. The ARDL-NARNN technique with the incorporation of meteorological drivers can be used to forecast the future epidemic trends of scarlet fever. These findings may be of great help for the prevention and control of scarlet fever.

Prevalence of Streptococcus pneumoniae in conjunctival flora and association with nasopharyngeal carriage among children in a Vietnamese community

Conjunctival pneumococcal serotypes among members of a community have not been investigated well. We determined the prevalence and association of Streptococcus pneumoniae in the nasopharynx and conjunctiva among children in a community before pneumococcal conjugate vaccine introduction. In October 2016, conjunctival and nasopharyngeal swabs were collected from children (< 24 months old) and nasopharyngeal swabs from mothers in Nha Trang, Vietnam. Quantitative lytA PCR and DNA microarray were performed to detect and serotype S. pneumoniae. The association between S. pneumoniae in the nasopharynx and conjunctiva was evaluated using multivariable logistic regression model. Among 698 children, 62 (8.9%, 95% CI 6.9-11.2%) were positive for S. pneumoniae in the conjunctiva. Non-encapsulated S. pneumoniae were most commonly identified, followed by serotypes 6A, 6B, and 14. Nasopharyngeal and conjunctival detection were positively associated (aOR 47.30, 95% CI 24.07-92.97). Low birth-weight, day-care attendance, and recent eye symptoms were independently associated with S. pneumoniae detection in the conjunctiva (aOR 11.14, 95% CI 3.76-32.98, aOR 2.19, 95% CI 1.45-3.31, and aOR 3.59, 95% CI 2.21-5.84, respectively). Serotypes and genotypes in the conjunctiva and nasopharynx matched in 87% of the children. Three mothers' nasopharyngeal pneumococcal samples had matched serotype and genotype with their child's in the conjunctiva and nasopharynx. S. pneumoniae presence in nasopharynx and conjunctiva were strongly associated. The high concordance of serotypes suggests nasopharyngeal carriage may be a source of transmission to the conjunctiva.

Seasonal variation in acute post-cataract surgery endophthalmitis incidences in South Korea

PURPOSE

Previous studies have reported conflicting results on the influence of seasons on post-cataract surgery endophthalmitis incidences. This study aimed to investigate the seasonality associated with the incidence of postoperative endophthalmitis, and to evaluate its association with climate variables in South Korea.

SETTING

South Korea.

DESIGN

Retrospective cohort study.

METHODS

The postoperative endophthalmitis incidences were identified using the Health Insurance Review and Assessment Service claim data from July 2014 to June 2017. The monthly climate data were obtained from the Korea Meteorological Administration. The incidences of endophthalmitis were analyzed by the month of the year, and by the season. The association between postoperative endophthalmitis and the climatic variables, including mean temperature, relative humidity, precipitation, and hours of sunshine, was investigated.

RESULTS

The incidences were the highest in July, and they were the most prevalent during the summer months, although fewer cataract surgeries were performed in the summer months than during the rest of the year. The postoperative endophthalmitis incidences tended to increase with increasing relative humidity and increasing precipitation.

CONCLUSIONS

The incidences of post-cataract surgery endophthalmitis peaked during the hot and humid months. Understanding the seasonal and climatic influences on postoperative infection might help in risk stratification and outcome improvisation after the cataract surgery is performed.

The ocular surface bacterial contamination and its management in the prophylaxis of post cataract surgery endophthalmitis

Objective: To investigate the recent pieces of evidence regarding the bacterial ocular surface contamination and its treatment in the prophylaxis of post-cataract surgery endophthalmitis. Methods: We conducted a literature research on the topic of interest and selected the most relevant data. Results: The studies reported a relatively high rate of positive conjunctival culture and the most frequently isolated organism was Coagulase negative Staphylococcus, which is also the most common etiological agent of the postoperative endophthalmitis. The bacterial ocular surface load is influenced by age, climate, associated diseases, topical and systemic medication. The use of povidone-iodine alone or in association with levofloxacin eyedrops as prophylactic method is effective in reducing the conjunctival bacterial contamination and consequently decreases the incidence of postoperative endophthalmitis. Conclusions: Based on the current pieces of evidence, adequate treatment of the bacterial ocular surface contamination prior to cataract surgery seems to be effective in preventing endophthalmitis after cataract surgery. Abbreviations: EU = European Union, Spp. = Species, HIV = Human Immunodeficiency Virus.

Association between extreme heat and hospital admissions for cataract patients in Hefei, China

Cataract is the first cause of blindness and the major cause of visual impairment worldwide. Under conditions of global warming, researchers have begun to give attention to the influence of increasing temperature on cataract patients. Our paper aimed to investigate the association between extreme heat and hospital admissions for cataract in Hefei, China. Based on data from the New Rural Cooperative Medical System and National Meteorological Information Center, we used a generalized additive model and a distributed lag nonlinear model to examine the relationship between extreme heat and hospitalizations for cataract, with consideration of cumulative and lagged effects. When current mean temperature was above 28 °C, each 1 °C rise was associated with a 4% decrease in the number of cataract admissions (RR = 0.96, 95% CI = 0.94-0.98). The cumulative relative risk over 11 days of lag was the lowest, which indicated that every 1 °C increase in mean temperature above 28 °C was associated with a 19% decrease in the number of hospital admissions for cataract (RR = 0.81, 95% CI = 0.75-0.88). In subgroup analyses, the negative association between extreme heat and hospital admissions for cataract was stronger among patients who were not admitted to provincial-level hospitals. In conclusion, this paper found that extreme heat was negatively associated with cataract hospitalizations in Hefei, providing useful information for hospitals and policymakers.

Assessment of conjunctival flora in eyes with lacrimal passage obstruction before and after successful dacryoendoscopic recanalisation

BACKGROUND

To investigate conjunctival bacterial flora in eyes with lacrimal passage obstruction before and after dacryoendoscopic recanalisation with lacrimal tube intubation.

METHODS

One-hundred fifty eyes with lacrimal passage obstruction that were successfully treated by dacryoendoscopic recanalisation were enrolled. Conjunctival sampling was done for each eye before and 4 months after surgery. The lower fornix was rubbed by a sterile cotton swab, and the collected samples were cultured with several agar plates. Colonies were differentiated and enumerated by standard bacteriological laboratory techniques.

RESULTS

Positive bacterial growth was detected in 42.0% of all the samples before surgery, and the positivity rate significantly decreased to 26.0% after surgery (p=0.0051). The number of strains detected also decreased from 20 before surgery to 9 after surgery, especially pathogenic microorganisms decreased. In addition, drug-resistant bacteria such as penicillin-resistant Streptococcus pneumoniae and methicillin-resistant Staphylococcus aureus were detected in nine eyes before surgery but were detected only in one eye after surgery. Coagulase-negative Staphylococci and Corynebacterium spp., which are common in normal conjunctival flora, accounted for 46.5% of all the isolates before surgery and 80.9% after surgery, showing a significant increase in the rate after surgery (p<0.0001).

CONCLUSIONS

This study showed that physiological recanalisation of lacrimal passage after dacryoendoscopic surgery significantly decreased the culture positivity rate of conjunctival sac and the number of microorganism strains detected. It also decreased the number of potentially pathogenic and drug-resistant bacteria and increased the percentages of indigenous bacteria, causing the normalisation of conjunctival flora.

Bacteriological profiles and drug susceptibility of Streptococcus isolated from conjunctival sac of healthy children

BACKGROUND

To investigate bacterial flora and antibiotics susceptibility of Streptococcus pneumoniae isolated from the conjunctival sac of heathy children.

METHODS

Bacteria were isolated from the secretions of conjunctival sac of healthy children between 2015 and 2018. Antimicrobial susceptibility of isolated S. pneumoniae strains were determined using microbroth dilution method.

RESULTS

The sac secretions were collected from a total of 6440 children. 1409 samples presented bacterial growth, accounting for 21.8% of the samples. Among the 22 bacterial species isolated, 528 samples presented Gram-positive Staphylococcus spp. growth, accounting for 37.4% of the isolates, followed by Corynebacterium spp., counting for 30% of the isolates and Streptococcus pneumoniae, counting for 21.4% of the isolates. Antibiotics susceptibility tests showed that the majority of S. pneumoniae isolates were sensitive to most antibiotics tested. However, 72.8 and 81.2% of the isolates were resistant to erythromycin and tetracycline, respectively, and over 10% of them were resistant to gentamicin, tobramycin and rifampicin.

CONCLUSIONS

The bacterial flora of healthy children is mainly consisted of Gram-positive bacteria belonging to Corynebacterium spp. and Streptococcus spp.; most of S. pneumoniae isolates were sensitive to antibiotics except erythromycin and tetracycline.

Bacterial Flora of the Conjunctiva One Year after Dacryocystorhinostomy

PURPOSE:

The purpose of this study was to evaluate the changes of conjunctival bacterial flora 1 year after successful dacryocystorhinostomy (DCR).

METHODS:

Seventy-two consecutive adult patients with successful DCR were enrolled in this study. We obtained conjunctival cultures from the operated eyes, fellow eyes, and nasal mucosa of the operated side 1 year after the operation. After the period of incubation, further evaluation was performed using standard laboratory techniques.

RESULTS:

In the conventional media, positive bacterial growth was detected in 48 (66.7%) of the 72 operated eyes and in 31 of the 72 normal fellow eyes (43.1%). Nasal specimens were positive for bacterial growth in 65 (90.3%) patients. Isolation rate was significantly different between the operated and the fellow (nonoperated) eyes (P = 0.0074). Colony count, type, and frequencies of bacterial isolation from the operated eyes were similar to nonoperated eyes.

CONCLUSION:

One year after DCR, conjunctival bacterial isolation rate increased compared with the normal fellow eyes. Remote DCR may be considered as a local risk factor for developing postoperative endophthalmitis.

Microbial flora and resistance in ophthalmology: a review

Antibiotic resistance in systemic infection is well-researched and well-publicized. Much less information is available on the resistance of normal ocular microbiome and that of ophthalmic infections. An understanding of the distribution of ocular microorganisms may help us in tailoring our empiric treatment, as well as in choosing effective pre-, peri- and postoperative management, to achieve the best results for patients. This study aims to summarize and review the available literature on the subject of normal ocular flora and its resistance, as well as the broader topic of antibiotic resistance in ophthalmology.

Climate and season: the effects on ophthalmic diseases

Seasonal changes and climate have a significant impact on human health. Diseases influenced by temperature and climate conditions are likely to undergo dynamic pattern shifts with consequent impact on human health. A number of infectious and non-infectious ophthalmic diseases are influenced by temperature and seasonality. Awareness of this is important from public and global health perspective in addition to resource allocation strategies. We examine the evidence for a seasonal pattern to ophthalmic diseases and assess the possible impact of climate change.

Impact of meteorological changes on the incidence of scarlet fever in Hefei City, China

Studies on scarlet fever with meteorological factors included were few. We aimed to illustrate meteorological factors' effects on monthly incidence of scarlet fever. Cases of scarlet fever were collected from the report of legal infectious disease in Hefei City from 1985 to 2006; the meteorological data were obtained from the weather bureau of Hefei City. Monthly incidence and corresponding meteorological data in these 22 years were used to develop the model. The model of auto regressive integrated moving average with covariates was used in statistical analyses. There was a highest peak from March to June and a small peak from November to January. The incidence of scarlet fever ranges from 0 to 0.71502 (per 10⁵ population). SARIMAX (1,0,0)(1,0,0)₁₂ model was fitted with monthly incidence and meteorological data optimally. It was shown that relative humidity (β = -0.002, p = 0.020), mean temperature (β = 0.006, p = 0.004), and 1 month lag minimum temperature (β = -0.007, p < 0.001) had effect on the incidence of scarlet fever in Hefei. Besides, the incidence in a previous month (AR(β) = 0.469, p < 0.001) and in 12 months before (SAR(β) = 0.255, p < 0.001) was positively associated with the incidence. This study shows that scarlet fever incidence was negatively associated with monthly minimum temperature and relative humidity while was positively associated with mean temperature in Hefei City, China. Besides, the ARIMA model could be useful not only for prediction but also for the analysis of multiple correlations.

Ocular surface microbiome in meibomian gland dysfunction

BACKGROUND

To investigate the ocular microbiome in meibomian gland dysfunction in Auckland, New Zealand.

DESIGN

Prospective, cross-sectional, observational, university-based study.

PARTICIPANTS

Participants resident in New Zealand for ≥2 years (n = 157) were classified as normal (n = 66), mild (n = 41) or moderate-to-severe meibomian gland dysfunction (n = 50). Contact lens wear and anterior blepharitis status were recorded, as well as symptoms and clinical features.

METHODS

Bacteria collected from lid margin swabs, before and after gland expression, were isolated and identified by conventional microbiological culture techniques. Aerobic isolates were identified in all 157 participants, and both aerobic and anaerobic bacteria isolated in a subset of 87 subjects.

MAIN OUTCOME MEASURES

Bacterial incidence according to meibomian gland dysfunction status RESULTS: Symptoms, bulbar hyperaemia, conjunctival staining, lipid layer grade and tear film stability, but not corneal staining, showed moderate association with meibomian gland dysfunction severity. Participants with and without meibomian gland dysfunction showed a similar microbiome, unaffected by gland expression. Anterior blepharitis, a common co-morbidity, was not an independent predictor of the microbiome. Sterile cultures were more common in contact lens wearers than non-wearers. The incidence of Staphylococcus aureus was higher than anticipated across all severity groups, and that of coagulase-negative Staphylococcus, Corynebacterium and streptococci was lower.

CONCLUSIONS

Modest differences in relative proportions of bacteria compared with other studies support climatic variations in the ocular surface microbiome. Similarity in microbiome profile, irrespective of meibomian gland dysfunction severity, anterior blepharitis presence or contact lens wear, suggests potential for commonality in treatment.

Evaluation of conjunctival bacterial flora in a herd of goats in the Midwestern United States

OBJECTIVE

To identify conjunctival bacterial flora in healthy adult and newborn kid goats in the Midwestern United States and to compare vaginal and ocular surface flora in dam-kid pairs.

ANIMALS STUDIED

Thirty mixed-breed (crosses between Boer, Kiko, and Syfan Spanish) goats, 20 adult does and 10 newborn kids.

PROCEDURES

One eye of 15 adult goats (n = 15 eyes) and 5 kids (n = 5 eyes) was randomly selected. A subset of 5 adults (n = 10 eyes) and 5 kids (n = 10 eyes) underwent bilateral sampling. Each recently kidded dam's vaginal canal (n = 10) was also sampled. Two swabs were collected from each sample site for aerobic bacterial culture and Mycoplasma and Chlamydia spp. PCR.

RESULTS

Of the animals with positive cultures, Staphylococcus and Streptococcus were the most common bacterial genera from the conjunctival sac of adult (16/17; 94%) and kid (5/5; 100%) goats; three adults and 5 kids had no growth of bacteria on aerobic culture. Moraxella bovoculi was the most common single bacteria in adults, in 9 eyes (36%) of 8 animals (40%). Staphylococcus equorum was identified in all 5 kids with positive cultures. Mycoplasma sp. DNA was detected in 7 animals. Chlamydia sp. DNA was not detected in any sample. Four of 10 dam-kid pairs had identical bacteria isolated from the dam's vaginal sample and the kid's conjunctival sample.

CONCLUSIONS

Staphylococcus and Streptococcus were the most common conjunctival bacterial genera in this goatherd. Moraxella bovoculi was the most common single bacteria isolated from adults, and Staphylococcus equorum was the most common bacteria in kids. Mycoplasma sp. occurred infrequently at the ocular surface of adult and kid goats. A convincing association between dam-kid vaginal-conjunctival samples was not identified.

Clinical features of infectious endophthalmitis in South Korea: a five-year multicenter study

BACKGROUND

To investigate clinical features of infectious endophthalmitis over five years in a South Korean population.

METHODS

Medical records of consecutive patients diagnosed with infectious endophthalmitis at eight institutions located in Gyeongsangnam-do and Pusan city between January 1, 2004 and July 31, 2010 were reviewed.

RESULTS

A total of 197 patients were diagnosed and treated. An average of 30.0 infectious endophthalmitis per year was developed. The annual incidence rate of postoperative endophthalmitis during 2006~2009 was 0.037%. The ratios of male to female and right to left were 50.2%: 49.8 % and 54.8%: 43.2%, respectively. Eighth decade and spring were the peak age (36.6%) and season (32.0%) to develop the infectious endophthalmitis. The most common past history in systemic disease was hypertension (40.4%), followed by diabetes (23.4%). Cataract operation (60.4%) was the most common cause, among which most of them was uneventful phacoemulsification (95.9%). Corneal laceration (51.6%) and liver abscess (42.9%) were the most common causes of traumatic and endogenous endophthalmitis, respectively. The percentages of patients with initial and final visual acuity less than counting fingers were 62.6% and 35.2%, respectively. Treatment with vitrectomy with or without intravitreal antibiotics injection was administered to 72.6% of patients, while 17.3% received intravitreal antibiotics only.

CONCLUSIONS

Our study revealed that the development of infectious endophthalmitis was related with seasonal variation and increased during our study period. Pars plana vitrectomy was preferred for the treatment of infectious endophthalmitis in South Korea.

[Spectrum and susceptibility of preoperative conjunctival bacteria]

PURPOSE

To describe the conjunctival bacterial spectrum of our patients undergoing intraocular surgery and their antibiotic sensitivity during the study period.

METHODS

A retrospective study of preoperative conjunctival culture of patients consecutively scheduled for intraocular surgery from 21 February 2011 to 1 April 2013. Specimens were directly seeded onto blood-agar and MacConkey-agar (aerobiosis incubation, 2 days), and on chocolate-agar (6% CO2 incubation, 7 days). The identified bacteria were divided into 3 groups according to their origin; the bacteria susceptibility tests were performed on those more pathogenic and on some of the less pathogenic when more than 5 colonies were isolated. The sensitivity of the exigent growing bacteria was obtained with disk diffusion technique, and for of the non-exigent bacteria by determining their minimum inhibitory concentration. The Epidat 3.1 program was used for statistical calculations.

RESULTS

A total of 13,203 bacteria were identified in 6,051 cultures, with 88.7% being typical colonizers of conjunctiva (group 1), 8.8% typical of airways (group 2), and the remaining 2.5% of undetermined origin (group 3). 530 cultures (8.8%) were sterile. The sensitivity of group 1 was: 99% vancomycin, 95% rifampicin, 87% chloramphenicol, 76% tetracycline. Levels of co-trimoxazole, aminoglycosides, quinolones, β-lactams and macrolides decreased since 2007. The group 2 was very sensitive to chloramphenicol, cefuroxime, rifampicin, ciprofloxacin and amoxicillin/clavulanate. In group 3, to levofloxacin 93%, ciprofloxacin 89%, tobramycin 76%, but ceftazidime 53% and cefuroxime 29% decreased.

CONCLUSIONS

None of the tested antibiotics could eradicate all possible conjunctival bacteria. Bacteria living permanently on the conjunctiva (group 1) have achieved higher resistance than the eventual colonizers.

Aerobic bacterial flora of the normal conjunctiva at high altitude area of Shimla Hills in India: a hospital based study

AIM

To study the normal aerobic conjunctival flora in lower to mid Himalayan region of Shimla Hills.

METHODS

Samples from normal conjunctiva of 200 individuals above the age of 13 years who visited Indira Gandhi Medical College Hospital Shimla for refraction or cataract surgery were taken by anaesthetising the conjunctival sac with sterile 4% Xylocaine solution. Samples were obtained by gently rubbing lower fornix with a sterile cotton wool swab moistened with normal saline and keeping the eye lids wide apart to avoid contamination from lid margins. It was immediately inoculated in Brain Heart infusion and subjected to standard aerobic culture and identification techniques.

RESULTS

Totally, 72 eyes (36%) conjunctival sacs were sterile. Predominant aerobes isolated were Staphylococcus spp. in 120 (60%) followed by Haemophilus in 16 (8%), diphtheroids in 10 (5%), and Escherichia.coli (E. coli) in 4 (2%). A single aerobe was isolated from 98 eyes (49%) while 30 eyes (15%) yielded more than 1 aerobe. Staphylococcus epidermidis (S. epidermidis) was the most common bacterium, found alone in 58 eyes (29%) and in combination with another aerobe in 30 eyes (15%), followed by Staphylococcus aureus (S. aureus) in 18 (9%) and 10 eyes (5%) respectively.

CONCLUSION

S. epidermidis is the most common commensal organism followed by Haemophilus species. diphtheroids occupied the third position which otherwise are found more abundantly in literature. Pathogens like S. aureus, Staphylococcus citreus and E. coli were also found. Therefore, preoperative administration of topical broad spectrum antibiotics is extremely important in prophylaxis against ocular infection. The variation in microflora of normal conjunctiva in this part of world can be attributed to geographical, climatic and ethnic characteristics of the population under study.

[Clinical and microbiological features of severe infectious keratitis during heatwaves]

PURPOSE

To study clinical and microbiological features of patients with severe microbial keratitis during a heatwave. To evaluate the links between disease severity, causative micro-organisms and temperature variation.

METHODS

Retrospective study of patients with microbial keratitis hospitalized in a referral center during the summer months (between June 1, 2009 and September 30, 2009), separated into two groups by date of hospitalization (heatwave vs non-heatwave). Prevalence and daytime temperatures were compared for data collected during the summers of 2009 (heatwave), 2008 (temperate) and 2003 (prolonged heatwave).

RESULTS

Thirty-three patients were hospitalized during the summer of 2009, with an average age of 51 years and an average stay of 15 days. The primary predisposing factor was the use of contact lenses (36%), followed by pre-existing corneal disease (15%) and systemic disease (15%). Prevalence of severe keratitis was higher in periods of heatwaves vs periods of no heatwaves (mean 9.8 patients vs 3.1, P<0.001). Best corrected visual acuity progressed from 1/30 at admission to 1/10 at 1 month after discharge (P<0.001). The most common bacteria identified were Gram-positive cocci (CNS 27%) and Pseudomonas (23%). Microbiological results were similar in the two groups. Similar variations between the prevalence of severe keratitis and daytime temperatures were found for the summer of 2009 as well as for the summers of 2008 and 2003.

CONCLUSIONS

There appears to be a link between climatic temperature variations and the prevalence of severe microbial keratitis.

Pathogenic conjunctival bacteria associated with systemic co-morbidities of patients undergoing cataract surgery

PURPOSE

To identify the risk of patients undergoing cataract surgery of having pathogenic conjunctival bacteria associated with their systemic co-morbidities.

METHODS

Retrospective study of consecutive patients undergoing their first cataract operation from July 2005 to April 2010. Their preoperative conjunctival bacteria were cultured, identified, and classified in bacterial groups. Their co-morbidities were defined from their clinical data and the answers to systematic questions asked in the anaesthetic evaluation. The Microsoft Access databases of the two data sets were merged for carrying out the statistical analysis. Univariate association of each bacterial group with each co-morbidity was studied by using χ(2)-test for categorical data and Student's t-test for continuous variables. Also, logistic regression models were used adjusting for age and sex. SPSS statistic programme, version 18 was used for all these analyses. Endophthalmitis cases in this surgical series were searched.

RESULTS

In the 8333 selected patients, age was associated with increased conjunctival bacteria in all groups except for Streptococcus pneumoniae and Propionibacteriae. However, male sex was associated with these two groups and also with coagulase-negative Staphylococci, Corynebacterium xerosis, Staphylococcus aureus, and Gram-negative rods. After adjusting for age and sex, S. aureus was associated with diabetes, lung diseases, and renal and heart insufficiency; Gram-negative rods with smoking habit; Enterococci with diabetes; Streptococcus pneumoniae with kyphoscoliosis; and other Streptococci with diabetes and handicapped patients.

CONCLUSION

The more pathogenic conjunctival bacteria were more likely associated with patients' co-morbidities, such as diabetes, lung diseases, renal and heart insufficiency, kyphoscoliosis, and smoking habit, than the less pathogenic ones.

Seasonality of staphylococcal infections

Characterization of seasonal variation of Staphylococcus aureus is important in understanding the epidemiology of, and designing preventive strategies against this highly virulent and ever-evolving pathogen. In this review, we summarize the findings of epidemiological studies that have evaluated seasonality in S. aureus colonization and infection. Although most studies published to date are methodologically weak, some seasonal variation in the occurrence of S. aureus infection appears to exist, particularly an association of warm-weather months with S. aureus skin and soft-tissue infections. We highlight the limitations of the published literature, and provide suggestions for future studies on this topic.

The conjunctival bacterial pattern of diabetics undergoing cataract surgery

PURPOSE

To ascertain the conjunctival bacterial pattern of diabetics undergoing cataract operation to reduce the risk of postoperative endophthalmitis (PE).

METHODS

An observational retrospective study of the conjunctival bacteria of consecutive patients undergoing cataract surgery from July 2005 to November 2008. Records of patients having eye surgical prophylaxis in the 6 months before the culture and those patients having cataract operation combined with other surgical procedures were excluded. Aerobic and microaerobic cultures were carried out. Dade-Behring panels were used for bacterial identification. The database containing the isolated bacteria was linked to another Access database containing demographic and clinical data such as diabetes presence and baseline blood glucose and creatinine levels. The conjunctival bacteria of diabetics were compared with those of the non-diabetics. Epidat 3.1 program was used for statistical calculations.

RESULTS

From 5922 selected patients, 1325 (22.37%) knew they were diabetics (higher prevalence than expected). Among self-reported non-diabetics, 900 (15.2%) could be 'unknown' diabetics; another 274 had an impaired renal function; and 3423 non-diabetics joined the control group. Diabetics have a significantly higher prevalence of Staphylococcus aureus, Enterococci, certain Streptococci, and Klebsiella sp. than non-diabetics. Diabetics and non-diabetics having a blood creatinine level above 105.2 mumol/l had an increased conjunctival bacterial prevalence; these groups had a higher mean age and men predominated.

CONCLUSIONS

Diabetics have a conjunctival flora pattern whose increased bacteria are a predominant cause of many diabetic infections. An abnormally high blood creatinine level is an indicator of increased conjunctival colonisation in diabetics and non-diabetics.

Effect of antibacterial honey on the ocular flora in tear deficiency and meibomian gland disease

PURPOSE

To assess for differences in the ocular flora of patients with dry eye caused by tear deficiency and/or meibomian gland disease and to assess the effect of antibacterial honey on the ocular flora in these forms of dry eye.

METHODS

In this prospective, open-label pilot study, bacteria isolated from the eyelid margin and conjunctiva were identified and quantified before and at 1 and 3 months after initiation of treatment with topical application of antibacterial honey 3 times daily. Subjects had non-Sjogren tear deficiency (n = 20), Sjogren syndrome tear deficiency (n = 11), meibomian gland disease (n = 15), and non-Sjogren tear deficiency with meibomian gland disease (n = 20), and there were 18 non-dry eye subjects.

RESULTS

The total colony-forming units (CFUs) isolated from each of the dry eye subgroups before antibacterial honey use was significantly greater than the total CFU isolated from the non-dry eye group. Antibacterial honey use significantly reduced total CFUs for the eyelids and the conjunctiva of dry eye subjects from baseline at month 1 (eyelids: P = 0.0177, conjunctiva: P = 0.0022) and month 3 (eyelids: P < 0.0001, conjunctiva: P < 0.0001). At month 3, there were reductions in total CFUs for all dry eye subgroups such that the CFUs were not significantly different from those of the non-dry eye group.

CONCLUSION

From these results, there is sufficient preliminary data to warrant further study of the effects of antibacterial honey in chronic ocular surface diseases.

Ecologic effects on eye banking

PURPOSE

To examine the climatic conditions at corneal donation for microbial categories of postkeratoplasty endophthalmitis that have been reported to a national surveillance registry.

DESIGN

Retrospective case-control study.

METHODS

Local weather information on the date of donor corneal procurement was tabulated for reported cases of endophthalmitis after penetrating keratoplasty and then compared between candidal endophthalmitis and postsurgical endophthalmitis that yielded bacteria or no microorganisms or that were not cultured.

RESULTS

Compared with other postkeratoplasty endophthalmitis, candidal endophthalmitis after corneal transplantation occurred significantly (P < .001) more often when outdoor afternoon temperatures exceeded 75 F at the source eye bank than on cooler days.

CONCLUSION

Higher exterior temperatures at donation may be associated with an increased relative risk of candidal transmission by keratoplasty, but a chain of causation that links the donor's environment to the recipient's infection remains to be elucidated.

Cataract surgery practice and endophthalmitis prevention by Australian and New Zealand ophthalmologists

PURPOSE

Our aim was to examine current cataract surgery practice and the methods of chemoprophylaxis used in Australia and New Zealand, and to determine if these factors were related to self-reported incidence rates of postoperative endophthalmitis.

METHODS

All Fellows and trainees of the Royal Australian and New Zealand College of Ophthalmologists were surveyed about their cataract surgery practices and methods of chemoprophylaxis for the prevention of postoperative endophthalmitis. Associations between self-reported incidence rates of endophthalmitis and clinical practice were examined using multivariate Poisson regression modelling.

RESULTS

There were 731 respondents (81.6% of 896 surveyed) to the survey. Respondents reported a total of 162,120 cataract operations and 92 cases of endophthalmitis in 2003, a cumulative incidence of 0.057%. The self-reported incidence of endophthalmitis varied from 0.034% in Victoria to 0.56% in the Northern Territory. Topical antibiotics were used preoperatively by 46.7% compared with 97.4% postoperatively; while only 44.1% used subconjunctival antibiotics. The routine use of subconjunctival antibiotic halved the self-reported incidence of postoperative endophthalmitis (incidence rate ratio 0.53, 95% confidence interval 0.30-0.92).

CONCLUSIONS

Subconjunctival antibiotics may be beneficial in the prevention of endophthalmitis after cataract surgery.

ESCRS study of prophylaxis of postoperative endophthalmitis after cataract surgery

PURPOSE

To present the development and design of the European Society of Cataract & Refractive Surgeons multicenter study of the prevention of postsurgical infective endophthalmitis after phacoemulsification and to describe the process for its successful implementation and conduct.

SETTING

Twenty-four ophthalmology units and eye clinics in Austria, Belgium, Germany, Italy, Poland, Portugal, Spain, Turkey, and the United Kingdom, with an administrative office in Ireland, coordinating center in England, and data management and statistical unit in Scotland.

METHODS

This partially masked randomized placebo-controlled multinational clinical study was designed to evaluate prospectively the prophylactic effect of intracameral cefuroxime and/or perioperative topical levofloxacin on postoperative endophthalmitis after cataract surgery. Random allocation was based on a 2 x 2 factorial design that included participating centers as a class variable. Real-time electronic data collection monitored study progress and provided weekly outcome tables, monthly recruitment summaries, and quarterly analytical reports for the study's Data Monitoring Committee, which evaluated the safety and efficacy by Internet-based conferences.

RESULTS

A 2-year lead time was required to meet harmonized standards of clinical research in the European Union, obtain ministerial authorization in 3 countries, gain institutional approvals at 24 hospitals, and procure indemnity insurance for surgical centers. Informed consent instruments, designed to comply with national health policies, were translated into 8 languages. The use of information technology to collect study data enabled the organizers to evaluate individual eligibility at enrollment, adherence with study medications during and after surgery, and postoperative status during follow-up.

CONCLUSION

This international cooperative study provided the opportunity to estimate the current incidence of endophthalmitis after cataract surgery in Europe and determine whether 1 or both of 2 antimicrobial regimens reduces the risk for postsurgical intraocular infection.

Management and Outcomes of Postoperative Endophthalmitis since the Endophthalmitis Vitrectomy Study

PURPOSE

To examine if changes in the diagnosis and management of postoperative endophthalmitis have occurred since 1995, and to identify factors that might predict final visual outcome.

DESIGN

Retrospective, population-based, noncomparative, consecutive case series.

PARTICIPANTS

Patients with clinically diagnosed endophthalmitis after cataract surgery and lens-related surgery in Western Australia from 1980 to 2000.

METHODS

Endophthalmitis cases were identified using record linkage and cross-referencing with the surgical logbooks of vitreoretinal surgeons before validation by medical record review.

MAIN OUTCOME MEASURES

Microbiological data (microorganisms isolated and antibiotic susceptibilities), diagnostic interventions, surgical procedures, therapeutic interventions, and visual acuity (VA).

RESULTS

During the 21-year period, 213 episodes of endophthalmitis occurred after cataract surgery. Since 1995, both anterior chamber sampling and vitreous sampling have increased significantly. The overall use of vitrectomy has also increased, but we did not observe a difference according to presenting VA. Intravitreal antibiotic use increased significantly, whereas the use of both subconjunctival and IV antibiotics decreased. In one third of patients, the VA at least 6 months after admission for endophthalmitis was worse than 6/18. This was associated with treatment that did not include the use of oral antibiotics (odds ratio [OR], 3.86; 95% confidence interval [CI], 1.21-12.39; P = 0.02), growth from intraocular samples of organisms other than coagulase-negative staphylococci (OR, 9.84; 95% CI, 2.84-34.09; P<0.001), and a discharge VA worse than 6/18 (OR, 6.10; 95% CI, 1.63-22.89; P = 0.01).

CONCLUSIONS

Although we observed noticeable changes in the diagnosis and management of endophthalmitis since 1995, visual outcomes have not improved and remain poor. Our finding that treatment with oral antibiotics may be associated with a better visual outcome warrants further investigation.

Influence of age on conjunctival bacteria of patients undergoing cataract surgery

AIM

To ascertain the effect of elderly in the conjunctival bacteria frequency of patients undergoing cataract extraction.

METHODS

A retrospective case series study of 4432 consecutive patients who underwent cataract surgery, without excluding any of them for having pre-existing diseases. Their preoperative conjunctival culture were performed over a 3-year period (1994-1996). Bacteria were grouped in nine categories and patients were divided into seven groups, according to age; comparisons between groups were made by means of the chi(2) test, and the Mantel-Haenszel test to analyse age as a confounder, using SPSS program, version 12.

RESULTS

Patients aged over 74 years accounted for 41.4%; women predominated among this group (61.4%), but not in the patients younger than 75 (47.7%); In the whole sample women accounted for 53.4%. Patients aged 75-96 years had a greater frequency of: Corynebacteria, Staphylococcus aureus, Streptococcus sp. (except Streptococcus pneumoniae), Gram-negative cocci and Gram-negative rods (except Haemophilus sp.) and 'other bacteria' categories than those aged 3-74 years. Different bacteria frequency in both sexes produced a confounding effect in the comparison between age-groups. Men had more Staphylococci coagulase (-), S. pneumoniae and Gram-negative rods than women.

CONCLUSIONS

Elderly patients awaiting cataract surgery had more conjunctival bacteria than those younger than 75 years, except Staphylococcus coagulase negative, S. pneumoniae and Haemophilus sp. At any age, men had more bacteria than women. These increments of frequencies could increase the risk of intraocular surgery contamination.

Eye-banking risk factors for fungal endophthalmitis compared with bacterial endophthalmitis after corneal transplantation

PURPOSE

To track the relative frequency and explore possible risk factors of fungal compared with bacterial endophthalmitis after corneal transplantation.

DESIGN

Case-comparison study nested in a surveillance registry.

METHODS

We examined, among recipients who underwent surgery from January 1991 through December 2003, demographic and eye-banking characteristics of postkeratoplasty endophthalmitis cases that were reported to the Eye Bank Association of America by US eye banks. Potential predictors of fungal compared with bacterial endophthalmitis were examined using multiple logistic regression.

RESULTS

Of 234 reported cases of postkeratoplasty endophthalmitis reported by US eye bank, 46 cases (19.7%) were fungal, and 130 cases (55.6%) were bacterial. Concordant cultures of the residual donor corneoscleral rim or preservation medium occurred significantly more often with fungal than bacterial endophthalmitis (P = .009). After the introduction of Optisol-GS, the odds of bacterial relative to fungal endophthalmitis decreased by 77% (95% confidence interval, 44% - 91%). After adjustment for the preservation method and other eye-banking variables, the odds of fungal endophthalmitis was 3.4 (95% confidence interval, 1.6 - 7.4) times that of bacterial endophthalmitis, when donor corneal preservation was 4 days or longer.

CONCLUSIONS

The frequency of postkeratoplasty bacterial endophthalmitis compared with fungal endophthalmitis fell after widespread use of a corneal preservation medium supplemented with gentamicin and streptomycin. Further improvements in corneal preservation procedures are needed.