Maria Cecília Zorat Yu

Microbial keratitis in the elderly: a 32-year review

PURPOSE To describe the demographic characteristics, associated factors and causative agents of infectious keratitis in the elderly in a tertiary referral center in São Paulo, Brazil. METHODS A retrospective review of all patients aged 60 years and over with a presumptive diagnosis of infectious keratitis who had material collected for microbiological analysis, between the years 1975 and 2007 (32-year span). RESULTS From a total of 7,060 age-independent cases of microbial keratitis, 1,545 cases in the elderly were reviewed, which had a mean age of 71.0 ± 7.8 years, ranging from 60 to 101 years. There were 707 males (45.6%) and 838 females (54.3%). Associated factors were: past ocular surgery (25.1%), ocular trauma (7.2%) and contact lens use (3.0%). Bacterioscopy was positive in 40.5% of cases. Culture positivity for any agent was 53.5% (bacteria 47.0%, fungi 6.1%, Acanthamoeba 0.4%). The most frequent bacteria were the gram-positive cocci (mostly coagulase-negative Staphylococci) and gram-negative bacilli (mostly the genera Pseudomonas, Moraxella and Proteus), while the most frequent fungi were the filamentous (mostly the genus Fusarium). CONCLUSIONS This study represents a large series of microbial keratitis in the elderly in a single referral center. The most important factor associated with this condition in the elderly was past ocular surgery. The most frequent causative agents were bacteria, especially gram-positive cocci and gram-negative bacilli.

Evaluation of normal ocular bacterial flora with two different culture media.

BACKGROUND The purpose of this study was to determine if the use of broth culture medium is efficient in investigating bacterial flora of the normal eyelid and conjunctiva. METHODS Samples from the conjunctiva and eyelid of healthy patients of various ages who were undergoing ocular surgeries were obtained and cultured at 3 periods: before topical antibiotic prophylaxis, in the postoperative period during topical antibiotic treatment, and 15 days after discontinuation of antibiotic use. Samples were inoculated into both brain heart infusion broth and blood agar plate, and the growth results of both media were analyzed. RESULTS Brain heart infusion broth medium showed a significantly higher bacterial growth of gram-positive cocci in most periods. The solid blood agar medium had a higher recovery of gram-positive bacilli before prophylaxis only in the older patients. INTERPRETATION Our results show that a more complete analysis of eyelid and conjunctival flora can be obtained using both liquid and solid media to increase the chances of isolate recovery. The inclusion of liquid media in this analysis was even more relevant in the period of concomitant use of antibiotic treatment.

Fusarium keratitis in Brazil: genotyping, in vitro susceptibilities, and clinical outcomes

Background The purpose of this paper is to describe clinical characteristics and determine correlations between clinical outcomes and antifungal susceptibility among molecularly characterized ocular Fusarium isolates in Brazil. Methods Forty-one Fusarium isolates obtained from 41 eyes of 41 patients were retrieved from the ophthalmic microbiology laboratory at São Paulo Federal University and grown in pure culture. These isolates were genotyped and antifungal susceptibilities determined for each isolate using a broth microdilution method. The corresponding medical records were reviewed to determine clinical outcomes. Results The 41 isolates were genotypically classified as Fusarium solani species complex (36 isolates, 88%), Fusarium oxysporum species complex (two isolates, 5%), Fusarium dimerum species complex (one isolate, 2%) and two isolates that did not group into any of the species complexes. Final best corrected visual acuity varied from 20/20 to light perception and was on average 20/800 (logarithm of the minimum angle of resolution (LogMAR) 1.6). A history of trauma was the most common risk factor, being present in 21 patients (51%). Therapeutic penetrating keratoplasty was necessary in 22 patients (54%). Amphotericin B had the lowest minimum inhibitory concentration for 90% of isolates (MIC90) value (2 μg/mL) and voriconazole had the highest (16 μg/mL). There was an association between a higher natamycin MIC and need for therapeutic penetrating keratoplasty (Mann–Whitney test, P < 0.005). Conclusion Trauma was the main risk factor, and therapeutic penetrating keratoplasty was necessary in 54% of patients. Amphotericin B had the lowest MIC90 (2 μg/mL) of the three antifungal agents tested. There was an association between higher natamycin MIC levels and corneal perforation, emphasizing the need for antifungal susceptibility testing and tailoring of antifungal strategies.

Incidence of endophthalmitis after cataract surgery (2002-2008) at a Brazilian university-hospital

PURPOSE To report on the incidence, diagnostic technique, and microbiological features of endophthalmitis at a university-setting in Brazil. METHODS All cases of presumed postoperative endophthalmitis from 2002 to 2008 at a teaching-hospital were included. Main data assessed were: number of cataract surgeries performed, incidence of endophthalmitis, microbiological outcome (aqueous and/or vitreous culture and Gram staining), and antimicrobial susceptibility testing of the positive cases. RESULTS Seventy-three eyes of 73 patients (43 females and 30 males) developed endophthalmitis after 24,590 cataract surgeries. The incidence decreased from 0.49% in 2003 to 0.17% in 2006 and stabilized afterwards. Coagulase negative Staphylococci (CoNS) and Streptococcus viridans (56.5% and 15%, respectively) were the most common bacterial isolates. Culture and Gram stain were negative in 36.9%. CoNS presented susceptibility rates of 80%-sensitivity to oxacillin, 90% to fourth-generation quinolones and 100% to vancomycin. CONCLUSIONS The rate of endophthalmitis, diagnostic ability of conventional laboratory investigation, microbial isolates and antibiotic susceptibility are in accordance with other findings of the literature. Despite using prophylactic antibiotic drops, it was possible to identify cases that were susceptible to the antibiotics topically applied.

[Culture proven bacterial endophthalmitis: a 6-year review].

PURPOSE To assess the distribution of microorganisms isolated from patients with bacterial endophthalmitis and their antimicrobial susceptibility. METHODS Retrospective analysis of medical and microbiological records of patients with suspected diagnosis of endophthalmitis and bacterial culture-proven at the Department of Ophthalmology, UNIFESP, between January 1 2000 and December 31 2005. RESULTS 153 (33.9%) of 451 patients showed positive bacterial culture. A total of 155 microorganisms were isolated, 79.35% were gram-positive and 20.65% gram-negative. Staphylococcus (CoNS) (41.94%) were the most frequently isolated. The antimicrobial susceptibility for gram-negative microorganisms was as follows: amikacin 87.10%, tobramycin 80.65%, ciprofloxacin 96.67%, levofloxacin, gatifloxacin and moxifloxacin 100%, ceftazidime 85.0%, and gentamicin 80.65%. Vancomycin sensitivity among gram-positive microorganisms was 100%. S. aureus and CoNS showed 83.33% of susceptibility to oxacillin, 89.61% to ciprofloxacin and 100% to gatifloxacin and moxifloxacin. The main acquisition mechanism was postoperative (60.65%). CONCLUSION We detected a low sensitivity of vitreous/aqueous culture for the etiologic diagnosis of endophthalmitis. The empiric antimicrobial therapy or prophylaxis should be active against gram-positive bacteria, particularly staphylococci. Surveillance studies of bacterial resistance are important for a better utilization of antimicrobials in this clinical setting.

Análise laboratorial de ceratites fungicas em Serviço Universitário

Purpose: To present the frequency and type of identified fungi from infectious keratitis. Methods: Retrospective survey of the cases of mycotic keratitis in the period from 1995 to 1998, at the Laboratory of Ocular Microbiology of the Department of Ophthalmology of the Federal University of Sao Paulo. Description of the fungal isolations, analysis of the causative factors and relation to the number of infectious keratitis in the same period. Results/Conclusion: Mycotic keratitis was diagnosed in 61 (5.48%) of the 1,113 patients who presented ulcer of the cornea of infectious etiology, ranging from 3.4 to 9.25%, per year. Filamentous fungi were identified in 47 cases (77.04%) and yeasts in 14 (22.95%). Fusarium was the most frequent genus (50.82%), followed by Candida (22.95%) and Aspergillus (8.19%). Phaeosiaria sp, Phoma sp, Fonsecaea pedrosoi, Exserohilum rostratum, that are rare etiological fungal agents of keratitis, were also isolated.

Suscetibilidade antimicrobiana in vitro dos Staphylococcus coagulase negativa oculares

PURPOSE: To assess the in vitro susceptibility of conjunctival and corneal coagulase negative Staphylococcus (CoNS) to methicillin, fluoroquinolones and aminoglycosides. METHODS: A total of 707 conjunctival and corneal CoNS disk diffusion test results were retrospectively analyzed, from January 2000 through December 2003. RESULTS: From 2000 to 2003, there was an increase in number of CoNS isolated from conjunctiva (n=57 to n=153) and cornea (n=28 to n=78). The frequency of conjunctival and corneal methicillin-resistant CoNS also increased (1.8 to 19.6% and 14.3 to 29.3%, respectively). There was no statistically significant difference between fluoroquinolones-resistant CoNS percentages in conjunctiva (ofloxacin: 1.8 to 7.8% and ciprofloxacin: 3.5 to 9.2%) and cornea (ofloxacin: 14.3 to 9.0% and ciprofloxacin: 14.3 to 10.3%). Evaluating the results of the conjunctival samples, there was increased resistance to tobramycin (15.8 to 34.0%) and to gentamycin (10.5 to 25.5%). There was no change in resistance of corneal isolates to tobramycin (28.6 to 26.9%) and to gentamycin (21.4 to 23.1%). CONCLUSIONS: there was a decrease in in vitro CoNS susceptibility to methicillin, tobramycin and gentamycin. Fuoroquinolones represented by ofloxacin and ciprofloxacin demonstrated stable in vitro susceptibility.

Decontamination of human sclera: an in vitro study.

PURPOSE: To report a case of Mycobacterium avium-intracellulare (MAI) keratitis successfully treated with topical clarithromycin. An unreported side effect of the topical medication is described. METHODS: A regular follow-up in the corneal clinic was arranged, and a pertinent literature search performed. RESULTS: The use of topical clarithromycin was successful in treating the keratitis. The patient did not complain of any ocular discomfort. Corneal subepithelial deposits that appeared during treatment with clarithromycin resolved shortly after the therapy was discontinued. CONCLUSION: This case report demonstrates that a rare infection like MAI keratitis can be successfully treated with topical clarithromycin. It also highlights the possible corneal deposition of this drug, which resolved after cessation of therapy.PURPOSE The human sclera is frequently used in ophthalmic surgeries and must be preserved in disinfectants that prevent its contamination. In this study the efficiency of glycerin, absolute alcohol (ethanol), and benzalkonium chloride (1:5,000) as human sclera disinfectants were compared. METHODS Fresh human scleras were trephined, the scleral disks divided into three groups and contaminated with Staphylococcus aureus (ATCC 29213), Pseudomonas aeruginosa (ATCC 27853), or Bacillus cereus (ATCC 11778) for 24 h. Thereafter they were transferred to preservation vials each containing glycerin, absolute alcohol, benzalkonium chloride diluted in 70% alcohol (1:5,000) or Trypticase Soy Broth (control), respectively, and stored at room temperature. From each vial, two scleral disks were removed after 1, 2, 3, 4, 7, 10, and 14 days of immersion. Both were plated on blood agar, one being macerated, and both incubated at 37 degrees C for 48 h. RESULTS Pseudomonas aeruginosa, S. aureus, and B. cereus were recovered from the glycerin-immersed scleral disks until the second, fourth, and fourteenth days, respectively. Bacillus cereus was recovered from those immersed in absolute alcohol until the fourteenth day, whereas disks infected with the other microorganisms and immersed in absolute alcohol presented no growth since the very first day of immersion. Bacillus cereus was recovered from scleral disks immersed in benzalkonium chloride diluted in 70% alcohol (1:5,000) only on the first day. CONCLUSION Resistant microorganisms can survive in scleral tissue preserved in glycerin and absolute alcohol. We conclude that benzalkonium chloride diluted in 70% alcohol (1:5,000) in vitro is the best disinfectant for human sclera after 24 h.

Estudo da micobiota em conjuntiva sadia de diabéticos, residentes na área urbana da cidade de São Paulo - Brasil

PURPOSE: To determine the mycobiota of the healthy conjunctiva in diabetic individuals, according to diabetes type, age, sex, disease time, type of treatment, and stage of diabetic retinopathy of the individuals. To identify the anemophilus mycobiota in the sampling rooms. METHODS: A cross-sectional study was carried out on 803 diabetics who reside in the urban area of Sao Paulo-SP/Brazil. Sabourauds dextrose agar culture with chloramphenicol was used for primoisolation, and the key of De Hoog was used to identify filamentous fungi. RESULTS: Of the evaluated diabetics, 6.6% (53/803) presented type 1 diabetes and 93.4% (750/803) type 2. The positive cultures for fungi in the conjunctiva of diabetics was 4.2% (34/803), with 1.9% (1/53) in type 1 diabetics and 4.4% (33/740) in type 2 diabetics (p=0.720). With respect to the presence or not of isolated fungi, there was no statistically significant association regarding age (p=0.575), sex (p=0.517), disease time (p=0.633), type of treatment (p=0.422), and diabetic retinopathy stage (p=0.655) of the tested individuals. The identified fungi were all filamentous: Aspergillus spp. represented 59.5% (25/42) of isolations and 47.6% (20/42) of isolated species were Aspergillus niger. Growth of anemophilus fungi occurred in the air of the room and coincidences were observed between the isolated species from the air and those from the conjunctiva. CONCLUSIONS: Presence of mycobiota in healthy conjunctivas of diabetics was identified, with no significant association between the greater number of positive fungi isolations and the type of diabetes, age, sex, disease type, type of treatment, and stage of diabetic retinopathy. In the collection rooms, anemophilus mycobiota was identified.

Ultra-sonografia ocular em suspeita clínica de endoftalmite

Purpose: To determine ultrasonographic findings in patients with clinical diagnosis of endophthalmitis, a severe purulent inflammatory reaction confined to the interior of the eye. Methods: Ultrasound examination was performed (10MHz transducer, UltraScan® ALCON), during the period of 1997 to 1999. Results: We analyzed 25 eyes with a clinical diagnosis of endophthalmitis (23 exogenous, 2 endogenous). Twelve (12/23) were post-surgery (7 post-cataract surgery, 4 post-glaucoma surgery and 1 post-keratoplasty). Six followed penetrating trauma and 4 were after corneal ulcer. One patient had corneal suture and cataract surgery after penetrating trauma. Two of them presented low-reflectivity echoes, similar to the normal vitreous, and endophthalmitis was ruled out at that time. Twenty-three cases presented (at different degrees) vitreous involvement with low-mobility dense membranes, vitreous organization and vitreous cavitation. Diffuse choroidal thickening (12 cases), choroidal and/or retinal detachment (8 and 5 cases) and orbital abscess (1 case) were found. Conclusions: Ultrasound examination is important to help in clinical suspected endophthalmitis in order to determine the involvement of the posterior segment.