Bacterial keratitis in a tertiary hospital in São Paulo: a 21-year review of the epidemiological, laboratory, and clinical data

ABSTRACT Infectious keratitis is a sight-threatening condition that is usually an ocular emergency. The visual outcome depends on prompt and accurate clinical management as well as geographic and epidemiological awareness. We conducted a retrospective observational study to define the epidemiological and laboratory profile, as well as the clinical course of bacterial keratitis in a tertiary hospital in São Paulo over 21 years. Information about age, sex, predisposing factors, topical and surgical treatment, visual acuity, ulcers' classification, bacterioscopy, culture, and antibiotic sensitivity tests were collected. This study included 160 patients. The mean age was 65.1 ± 18.4 years and risk factors were identified in 83.1 % of the patients. Empirical topical fortified cephalosporin with an aminoglycoside or fourth-generation fluoroquinolone was curative for 66.2 % of the cases. The mean treatment duration was 22.5 ± 9 days. The mean variation of visual acuity was −0.25 logMAR, p < 0.001. Culture revealed 64 % of Gram-positive bacteria. All Gram-positive bacteria were sensitive to cephalothin, vancomycin, and quinolones. All Gram-negative bacteria were sensitive to gentamicin, tobramycin, amikacin, and ciprofloxacin. These findings reinforce the importance of prompt empirical treatment of severe corneal ulcers with a fortified cephalosporin and aminoglycoside or a fourth-generation fluoroquinolone as there are equally effective. Collected data was insufficient to evaluate resistance of ocular infections over time in this population.

Detection and antibiotic sensitivity test of Klebsiella peneumoniae in Ailurus fulgens / 中国人兽共患病学报

To confirm the etiology of a dead case for a 6 year-old female Ailurus fulgens,one strain of the predominant bacteria from pathologic tissues(heart,liver,spleen,lung and other samples) of the dead Ailurus fulgens were examined and isolated.The isolate was named R1 and no other bacteria were isolated.The bacterial etiological examination(morphological characteristics,biochemical characteristics and 16S rDNA gene detection)of R1 showed that it was identifed as K.peneumoniae.Artificial infection to mice about R1 was also conducted in this study.R1 had strong pathogenicity to mice and the LD50 is 6.5 × 104 CFU/mL.Moreover,the clinical and pathological features of the dead mice were consistent with that of the Ailurus fulgens.To find effective therapeutic drugs of curing other Ailurus fulgens,antibiotic sensitivity test of R1 was conducted,and the results revealed that R1 was highly sensitive to cefotaxime et al,moderately sensitive to amikacin and resistant to penicillin.These data showed that K.peneumoniae was bacterial pathogen leading to death of the Ailurus fulgens and it had strong resistance to penicillins,macrolides and virginiamycin and it had broad drug resistance spectrum.However,R1 is sensitive to cephalosporins and aminoglycoside antibiotics.

A brief research study on novel antibiotic producing isolate from VIT Lake, Vellore, Tamil Nadu.

The soil ecosystem has an enormous amount of microorganisms, and some of these microorganisms can potentially be useful to us. Bacillus and Actinomycetes are the most abundant microorganisms present in soil and both are known to produce antibiotics and inhibit the growth of other microorganisms. However, there are other potential microorganisms which may have such beneficial properties and are unknown to us. In this study, various microorganisms in the soil were screened to isolate an antibiotic producing microorganism. Soil was collected from VIT lake and serially diluted followed by crowded plate technique to screen for antibiotic producing colonies. The colony which was suspected to produce antibiotics was selected and sub-cultured by streaking. Antibiotic-sensitivity test was performed on Mueller-Hinton Agar and the inhibitory effect of the isolated microorganism towards the growth of bacteria was observed. The growth curve of the isolated microorganism was found out. Characterization was done by performing various biochemical tests and staining methods. Antibiotic production media was prepared, and the antibiotic production of the microorganism was plotted against time. From the antibiotic production curve, it was found that the 6th day showed the maximum antibiotic productivity.

Speciation of coagulase negative Staphylococcal isolates from clinically significant specimens and their antibiogram.

Background: Despite their frequency as contaminants, coagulase-negative Staphylococci (CONS) have become important nosocomial pathogens, accounting for 9% of all nosocomial infections. These infections are diffi cult to treat because of the risk factors and the multiple drug resistance nature of these organisms. Materials and Methods: One hundred and two consecutive CONS were isolated from various clinical samples like blood, pus, urine, urine catheter tip and gastric lavage. Most of the blood samples were from patients with risk factors (immunocompromised or on medical devices). After confi rming the isolates as CONS, species-level identifi cation was performed by simple, non-expensive conventional methods and antibiotic sensitivity testing was also carried out. Results: Of 102 CONS isolates, 100 isolates could be identifi ed to the species level. Among the 100 isolates, epidermidis was the most common species isolated, seen in 32%, followed by S. hemolyticus (18%), S. lugdunensis (12%), S. hominis (10%), S. saprophyticus (8%), S. capitis (6%), S. caprae (4%), S. xylosus (4%), S. cohni and S. warneri (3% each). In the present study, 56% of the isolates were methicillin-resistant CONS. Most of the isolates showed resistance to ampicillin and amoxyclav (89% each), followed by ceftriaxone (52%), cotrimoxazole (46%), cefotaxime (32%), gentamicin (25%), amikacin (21%). Conclusion: The increased pathogenic potential and multiple-drug resistance demonstrates the need to adopt simple, reliable and non-expensive methods for identifying and determining the antibiotic sensitivity of CONS.

In-vitro evaluation and comparison of the anti-microbial potency of commercially available oral hygiene products against Streptococcus mutans.

Background: Dental caries is the destruction of enamel, dentin, or cementum of teeth due to bacterial activities, which if left untreated can cause considerable pain, discomfort, and treatment costs are very high. Of the oral bacteria, Streptococcus mutans is considered to be causative agent of dental caries in humans. Aim: This study aims at screening the antibacterial potential of available oral hygiene products against S. mutans, the primary etiological agent. Materials and Methods: A selective number of toothpaste and mouth rinse available in the nearby local market was subjected to the study. The experiments were designed in a way to determine which one of these products had the greatest anti-S.mutans activity. Antibiotic sensitivity tests against the pathogenic strains were also conducted. Results and Discussion: Pathogenic strains of S.mutans were isolated from clinical dental specimen and identified using MTCC standard strain No. 890. Of the 86.66% samples which showed positive for S.mutans growth, almost 96% conferred sensitivity to 0.08 mg/ml of penicillin. Among the toothpastes used, A showed the maximum inhibitory activity against S.mutans inhibiting its growth even at a very low concentration of 0.0156 g/ml. Similar results were seen in the case of the mouth rinses used for the study, which showed that N had the most effective activity against S.mutans even at 1:8 dilution. Conclusion: The oral hygiene products containing triclosan proved to be the most effective followed by those containing fluoride. Herbal products showed comparatively lesser activity in inhibiting the growth of S. mutans. Even though there are so many products available to curb the progression of dental caries in the population targeted, there is still an undoubted prevalence and incidence of caries among the general public. The need for a better alternative to help control dental caries is on the rise even today.

Neonatal septicemia: Bacterial isolates & their antibiotics susceptibility patterns.

Background: Septicemia remains a significant cause of morbidity and mortality in the newborn, more so in developing countries due to delivery and postnatal follow up in an unclean environment having more chance of contamination with infective organisms. Moreover these infants are deficient in their inherent protective mechanisms, humoral and cellular immunity. The changing pattern and frequent emergence of resistant bacteria make the problem more difficult. Objectives: (1) To know the etiology of septicemia in neonates. (2) To detect the antibiotic susceptibility pattern of the isolates. Methods and Material: Blood samples were collected aseptically from 303 newborns admitted in NICU, Sir T Hospital, Bhavnagar during Jan-2006 to August-2008 with sepsis. The specimens were inoculated into brain heart infusion broth & subcultures were performed. The isolates were identified by standard biochemical tests. Antibiotic sensitivity pattern of isolates was studied by Modified Kirby Bauer Disc diffusion technique. Results: A total 140 (46.20%) organisms were isolated. These included Klebsiella (66, 47.14%), Staphylococcus aureus (35, 25%), Coagulase negative staphylococci (CONS) (5, 3.57%), E.coli (15, 10.71%), Proteus (5, 3.57%), Acinetobactor (3, 2.14%), Pseudomonas (6, 4.28%) and Candida (5, 3.57%). Majority of organisms isolated were resistant to commonly used antibiotics. Maximum sensitivity was seen by Cefoperazone/sulbactum (97%) & Piperacillin/tazobactum (98%) for Gram negative organisms & Vancomycin(100%) for Gram positive organisms. Conclusions: Multi-drug resistance organisms were isolated from septicemia in neonates. Therefore great caution is required in selection of antibiotic therapy.

A CLINICOBACTERIOLOGICAL STUDY ON WOUND INFECTION IN PATIENTS WITH ORAL AND MAXILLOFACIAL TRAUMA

A clinicobacteriological study on wound infection in patients with oral and maxillofacial trauma

Isolates of Bacteria and Their Sensitivity to Antibiotics in Fungal Maxillary Sinusitis / 대한이비인후과학회지

BACKGROUND AND OBJECTIVES: In patients with fungal sinusitis, purulent discharge from the maxillary sinus is frequently observed and it responds to antibiotic treatment. Even though fungal sinusitis is resolved after surgery, the purulent discharge continues in some cases. We aimed to identify the pathogens of the purulent discharge in fungal sinusitis and to obtain information for appropriate antibiotics through a sensitivity test. MATERIALS AND METHOD: Among 71 patients with fungal sinusitis of the maxillary sinus, purulent secretions were found in 44 patients (62%) during an endoscopic sinus surgery. Endoscope-guided collection of the maxillary sinus secretions were performed and specimens were sent to the laboratory for bacterial cultures and antibiotic sensitivity tests. RESULTS: Among 44 cases with fungal lesions and purulent secretion in the maxillary sinus, bacteria were isolated in 27 cases (61.4%). Gram (+) aerobes were recovered in 19 cases, and Gram (-) aerobes were recovered in 16 cases. Mixed infection by Gram (+) and Gram (-) bacteria were observed in 8 patients. Anaerobic bacteria were not isolated. Among the Gram (+) aerobes, S. aureus was the most common organism (8 cases), while Enterobacter aerogenes was the most common organism (7 cases) of the Gram (-) aerobes. In an antibiotic sensitivity test for Gram (+) bacteria, ciprofloxacin, vancomycin, and teicoplanin showed sensitivity over 85 %. For Gram (-) bacteria, ceftazidime, ciprofloxacin, ticarcillin, tobramycin, and imipenem showed sensitivity over 90%. CONCLUSION: In patients with fungal sinusitis, concomitant bacterial infections are identified in more than half of the cases. Thus, postoperative administration of appropriate antibiotics can be justified in the treatment of fungal sinusitis.

Epidemiologic Characteristics of T Serotyping in Relation to the Outbreak of Erythromycin Resistant Streptocccus pyogenes

PURPOSE: The identification of antigenic specificity of Streptococcus pyogenes using T serotyping is important to understand biologic characteristics of microorganisrns. We would like to disover the association of the occurrence of predominant T type, with possible outbreak of erythromycin resistant Streptococcus pyogenes in this country, which has been documented since the late 1990s. METHODS: Throat swab cultures were taken from a total of 1,294 normal school children(Subject A) in two different geographical areas. A total of 92 strains(Subject B) were obtained from the patients with group A streptococcal infections from Jan. 1998 to Dec. 1998. All strains were serotyped with T protein antisera. RESULTS: The distribution of T12 in Uljin increased from 4.2%(1996) to 45.7%(1998). T4 increased from 6.3% to 20.0%. Thirty-eight out of 92 strains were resistant to erythromycin. Twenty-seven out of 41 strains(T12) were multidrug resistant to erythromycin, clindarnycin, and tetracycline. CONCLUSION: We can see the sudden increase in T12 strains, one of the strains that are resistant to erythromycin in 1998, compared with previous years. T protein serotyping could be epidemiologically useful as a screening methods for detecting erythromycin resistant group A streptococci in hospitals where the routine antibiotic sensitivity test dose not examin for streptococci.

T Protein Serotyping and Antibiotic Sensitivity Test for Streptococcus pyogenes Obtained from Patients with Pharyngotonsillitis and Healthy School Children / 감염

BACKGROUND: In the mid-1970s and late 1980s, outbreaks of erythromycin-resistant streptococci in Japan and Finland were likely to be associated with the increased consumption of macrolides. Because of the lack of routine antibiotic sensitivity for Streptococcus pyogenes, the reported percentage of resistant strains was only 2% in 1994 in Korea. We tried to determine the rate of resistant strains considering the high occurrence of penicillin-resistant pneumococci and antibiotic purchase without prescription in our country. METHODS: Twenty-four strains of S. pyogenes were isolated from children with pharyngotonsillitis in Kyunghee University Hospital, Seoul, Korea from Feb. through Aug. 1998. Forty-four strains obtained from healthy school children living in Uljin, Kyongsang-bukdo and Hongreung, Seoul in 1998. All isolates were serotyped by T-agglutination (Sevapharma, Czech Rep) and minimal inhibitory concentrations were determined for penicillin, erythromycin, vancomycin, tetracycline, cefotaxime, and clindamycin by agar dilution method according to National Committee for Clinical Laboratory Standards. RESULTS: The carrier rates in Hongreung and Uljin were 4.1% and 13.3%, respectively. Twenty-two out of 24 (91.6%) strains from pharyngitis and 32 out of 44 (72.7%) strains from normal children were typed by T agglutination test. The most common T types were T12 (54.2%) and T4 (33.3%) in pharyngitis, whereas the most common T types were T12 (45.5%), non typable (27.3%), and T4 (15.9%) in healthy carriers. All of the strains from pharyngitis were susceptible to penicillin, vancomycin, and cefotaxime. However, 13 out of 24 (54.2%) strains were resistant to erythromycin, and 11 isolates (45.8%) were resistant to clindamycin and tetracycline. Ten out of 13 isolates of T12 and one isolate of T28 were multi-resistant to erythromycin, clindamycin, and tetracycline. Two isolates of T4 were resistant to erythromycin. CONCLUSION: Almost half of isolates obtained from a university hospital in Seoul are multidrug-resistant Streptococcus pyogenes. Serial monitoring of antibiotic susceptibility test and a nationwide survey accompanied by molecular epidemiologic studies are needed to determine the occurrence and spread of resistant strains from different geographic areas.