In Vitro Activities of Pexiganan and 10 Comparator Antimicrobials against 502 Anaerobic Isolates Recovered from Skin and Skin Structure Infections.

Pexiganan, a cationic peptide, exhibited a broad range of anti-anaerobic antimicrobial activity. The MIC90s of studied isolates were as follows: Bacteroides fragilis, 16 µg/ml; other B. fragilis group spp., 4 µg/ml; Prevotella and Fusobacterium spp., 32 µg/ml; Porphyromonas spp., 64 µg/ml; Propionibacterium acnes, 4 µg/ml; Eggerthella lenta and Peptostreptococcus anaerobius, 32 µg/ml; other Gram-positive rods and cocci, 4 µg/ml; Clostridium perfringens, 128 µg/ml; and other clostridia, 256 µg/ml. Pexiganan cream shows potential as adjunctive therapy for skin and skin structure infections (SSSIs) involving anaerobes.

Combined antioxidant effects of Neem extract, bacteria, red blood cells and Lysozyme: possible relation to periodontal disease.

BACKGROUND: The common usage of chewing sticks prepared from Neem tree (Azadirachta indica) in India suggests its potential efficacy in periodontal diseases. The objective of this study is to explore the antibacterial effects of Neem leaf extract on the periodontophatic bacteria Porphyromonas gingivalis and Fusobacterium nucleatum, and its antioxidant capacities alone and in combination with bacteria and polycationic peptides that may be at the site of inflammation. METHODS: Neem leaf extract was prepared by ethanol extraction. The growth kinetics of P. gingivalis and F. nucleatum under anaerobic conditions in the presence of Neem leaf extract were measured. Broth microdilution test was used to determine the Minimal Inhibitory Concentration (MIC) of Neem leaf extract against each bacterial strain. The effect of Neem leaf extract on the coaggregation of the bacteria was assessed by a visual semi-quantitative assay. The antioxidant capacities of Neem leaf extract alone and in combination with bacteria, with the addition of red blood cells or the polycationic peptides chlorhexidine and lisozyme, were determined using a chemiluminescence assay. RESULTS: Neem leaf extract showed prominent dose-dependent antibacterial activity against P. gingivalis, however, had no effect on the growth of F. nucleatum nor on the coaggregation of the two bacteria. Yet, it showed intense antioxidant activity, which was amplified following adherence to bacteria and with the addition of red blood cells or the polycationic peptides. CONCLUSIONS: Neem leaf extract, containing polyphenols that adhere to oral surfaces, have the potential to provide long-lasting antibacterial as well as synergic antioxidant activities when in complex with bacteria, red blood cells and lisozyme. Thus, it might be especially effective in periodontal diseases.

Clinical characteristics and antimicrobial susceptibilities of anaerobic bacteremia in an acute care hospital.

This study investigated the clinical features of anaerobic bacteraemia in an acute-care hospital, and evaluated the antimicrobial susceptibility of these isolates to commonly available antibiotics. Microbiological and epidemiological data from 2009 to 2011were extracted from the laboratory information system and electronic medical records. One hundred and eleven unique patient episodes consisting of 116 anaerobic isolates were selected for clinical review and antibiotic susceptibility testing. Susceptibilities to amoxicillin-clavulanate, clindamycin, imipenem, metronidazole, moxifloxacin, penicillin and piperacillin-tazobactam were performed using Etest strips with categorical interpretations according to current CLSI breakpoints. Metronidazole-resistant and carbapenem-resistant anaerobic Gram-negative bacilli were screened for the nim and cfiA genes. Clinical data was obtained retrospectively from electronic medical records. During the 3 year period, Bacteroides fragilis group (41%), Clostridium species (14%), Propionibacterium species (9%) and Fusobacterium species (6%) were the most commonly isolated anaerobes. Patients with anaerobic bacteraemia that were included in the study were predominantly above 60 years of age, with community-acquired infections. The most commonly used empiric antibiotic therapies were beta-lactam/beta-lactamase inhibitor combinations (44%) and metronidazole (10%). The crude mortality was 25%, and appropriate initial antibiotic therapy was not significantly associated with improved survival. Intra-abdominal infections (39%) and soft-tissue infections (33%) accounted for nearly three-quarters of all bacteraemia. Antibiotics with the best anaerobic activity were imipenem, piperacillin-tazobactam, amoxicillin-clavulanate and metronidazole, with in-vitro susceptibility rates of 95%, 95%, 94% and 92% respectively. Susceptibilities to penicillin (31%), clindamycin (60%) and moxifloxacin (84%) were more variable. Two multidrug-resistant isolates of Bacteroides species were positive for nim and cfiA genes respectively, while another two imipenem-resistant Fusobacterium species were negative for cfiA genes. This study demonstrated that anaerobic bacteraemia in our patient population was predominantly associated with intra-abdominal and soft-tissue infections. Overall antibiotic resistance was high for penicillin and clindamycin, and the presence of emerging resistance to carbapenems and metronidazole warrants further monitoring.

Severe forefoot infection complicated by Fusobacterium russii.

We present the first case of a complicated foot infection caused by Fusobacterium russii in Austria. F. russii is highly associated with mammals such as cats and dogs. Our case underlines the difficulties in isolation and identification of anaerobes and the pitfalls in antimicrobial treatment of polymicrobial infections.

Evaluation of antibiotic susceptibility of Bacteroides, Prevotella and Fusobacterium species isolated from patients of the N. N. Blokhin Cancer Research Center, Moscow, Russia.

In total 122 non-duplicate Bacteroides, Prevotella and Fusobacterium spp isolated from cancer patients between 2004 and 2014 were involved in this study. Most of the strains belonged to the B. fragilis group (55%), followed by Prevotella strains (34.4%) and Fusobacterium spp (10.6%). The species identification was carried out by matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS), and they were identified on species level with a log (score) >2.0. The most common isolates were B. fragilis, B. thetaiotaomicron, B. ovatus and B. vulgatus. Among Prevotella species, the most frequently isolated species were P. buccae, P. buccalis, P. oris, P. denticola and P. nigrescens, and most of the Fusobacterium spp. were F. nucleatum. Susceptibilities of the strains were determined by the E-test methodology. The percentage of the susceptibility of B. fragilis group isolates were: metronidazole (MIC ≤4 µg/ml), 97%; imipenem (MIC ≤2 µg/ml), 95.5%; amoxicillin/clavulanate (MIC ≤4 µg/ml), 95.5% and clindamycin (MIC ≤4 µg/ml), 77.6%. Three B. fragilis isolates proved to be multidrug-resistant (parallel resistance to imipenem, amoxicillin/clavulanate and metronidazole or clindamycin was observed). All Prevotella strains tested were susceptible to imipenem and amoxicillin/clavulanate, whereas 78.6% of the pigmented Prevotella species and 46.4% of the non-pigmented species were resistant to penicillin (MIC >0.5 µg/ml). The susceptibility to metronidazole and clindamycin were 93% and 88%, respectively. All Fusobacterium strains were sensitive to all tested antibiotics, including penicillin.

Activity of ceftolozane-tazobactam against a broad spectrum of recent clinical anaerobic isolates.

We evaluated in vitro activity of ceftolozane-tazobactam (TOL-TAZ), formerly CXA-201, against recent clinical anaerobic isolates with emphasis on the Bacteroides fragilis group. Ceftolozane-tazobactam showed good activity against B. fragilis species and intermediate to limited activity against other species of Bacteroides. Ceftolozane-tazobactam showed very good activity against Prevotella spp., Fusobacterium spp., and Propionibacterium spp., varying activities against Gram-positive cocci, and limited activity against Clostridium spp.

Periodontal effects of 0.25% sodium hypochlorite twice-weekly oral rinse. A pilot study.

BACKGROUND AND OBJECTIVE: The study aimed to evaluate the effect of 0.25% sodium hypochlorite twice-weekly oral rinse on plaque and gingivitis in patients with minimally treated periodontitis. MATERIAL AND METHODS: The study included 30 patients with periodontitis, it lasted 3 mo, and it was performed as a randomized, controlled, single-blinded, clinical trial in parallel groups. Fifteen patients rinsed for 30 s with 15 mL of a fresh solution of 0.25% sodium hypochlorite (test) and 15 patients rinsed with 15 mL of water (control). Clorox(®) regular bleach was the source of the sodium hypochlorite. At baseline and at 2 wk, the study patients received professional subgingival irrigation for 5 min with either 0.25% sodium hypochlorite or water, but no subgingival or supragingival scaling. The presence or absence of supragingival plaque on facial and lingual surfaces was determined by visual inspection; each tooth was dried with air and mouth mirror rotation was used to provide light reflection to identify plaque on smooth surfaces and at the tooth line angles. Gingival bleeding within 30 s after probing to full pocket depth was assessed in six sites of each tooth. Adverse events were evaluated by questionnaire and visual examination. RESULTS: All 30 patients in the study completed the baseline and the 2 wk parts of the study and a subset of 12 participants completed the 3 mo part of the study. The sodium hypochlorite rinse group and the water rinse group, respectively, showed increases from baseline to 3 mo of 94% and 29% (3.2-fold difference) in plaque-free facial surfaces, of 195% and 30% (6.5-fold difference) in plaque-free lingual surfaces, and of 421% and 29% (14.5-fold difference) in number of teeth with no bleeding on probing. The differences in clinical improvement between the sodium hypochlorite rinse group and the water rinse group were statistically significant. No adverse events were identified in any of the study patients, except for minor complaints about the taste of bleach. CONCLUSION: A twice-weekly oral rinse with 0.25% sodium hypochlorite produced marked decreases in dental plaque level and bleeding on probing and may constitute a promising new approach to the management of periodontal disease. Long-term controlled studies on the effectiveness of sodium hypochlorite oral rinse are needed and encouraged.

Antimicrobial effects of epigallocatechin-3-gallate, a catechin abundant in green tea, on periodontal disease-associated bacteria.

OBJECTIVE: Epigallocatechin-3-gallate (EGCG), a catechin abundant in green tea, exhibits antibacterial activity. In this study, the antimicrobial effects of EGCG on periodontal disease-associated bacteria (Porphyromonas gingivalis, Prevotella intermedia, Prevotella nigrescens, Fusobacterium nucleatum, and Fusobacterium periodontium) were evaluated and compared with its effects on Streptococcus mutans, a caries-associated bacterium. RESULTS: Treatment with 2 mg/ml EGCG for 4 h killed all periodontal disease-associated bacteria, whereas it only reduced the viable count of S. mutans by about 40 %. Regarding growth, the periodontal disease-associated bacteria were more susceptible to EGCG than S. mutans, based on the growth inhibition ring test. As for metabolism, the 50 % inhibitory concentration (IC50) of EGCG for bacterial metabolic activity was lower for periodontal disease-associated bacteria (0.32-0.65 mg/ml) than for S. mutans (1.14 mg/ml). Furthermore, these IC50 values were negatively correlated with the growth inhibition ring (r = -0.73 to -0.86). EGCG induced bacterial aggregation at the following concentrations: P. gingivalis (>0.125 mg/ml), F. periodonticum (>0.5 mg/ml), F. nucleatum (>1 mg/ml), and P. nigrescens (>2 mg/ml). S. mutans aggregated at an EGCG concentration of > 1 mg/ml. CONCLUSION: EGCG may help to prevent periodontal disease by killing bacteria, inhibiting bacterial growth by suppressing bacterial metabolic activity, and removing bacteria through aggregation.

The short-term treatment effects on the microbiota at the dorsum of the tongue in intra-oral halitosis patients--a randomized clinical trial.

OBJECTIVES: This study aims to assess the effects of rinsing with zinc- and chlorhexidine-containing mouth rinse with or without adjunct tongue scraping on volatile sulfur compounds (VSCs) in breath air, and the microbiota at the dorsum of the tongue. MATERIAL AND METHODS: A randomized single-masked controlled clinical trial with a cross-over study design over 14 days including 21 subjects was performed. Bacterial samples from the dorsum of the tongue were assayed by checkerboard DNA-DNA hybridization. RESULTS: No halitosis (identified by VSC assessments) at day 14 was identified in 12/21 subjects with active rinse alone, in 10/21 with adjunct use of tongue scraper, in 1/21 for negative control rinse alone, and in 3/21 in the control and tongue scraping sequence. At day 14, significantly lower counts were identified only in the active rinse sequence (p < 0.001) for 15/78 species including, Fusobacterium sp., Porphyromonas gingivalis, Pseudomonas aeruginosa, Staphylococcus aureus, and Tannerella forsythia. A decrease in bacteria from baseline to day 14 was found in successfully treated subjects for 9/74 species including: P. gingivalis, Prevotella melaninogenica, S. aureus, and Treponema denticola. Baseline VSC scores were correlated with several bacterial species. The use of a tongue scraper combined with active rinse did not change the levels of VSC compared to rinsing alone. CONCLUSIONS: VSC scores were not associated with bacterial counts in samples taken from the dorsum of the tongue. The active rinse alone containing zinc and chlorhexidine had effects on intra-oral halitosis and reduced bacterial counts of species associated with malodor. Tongue scraping provided no beneficial effects on the microbiota studied. CLINICAL RELEVANCE: Periodontally healthy subjects with intra-oral halitosis benefit from daily rinsing with zinc- and chlorhexidine-containing mouth rinse.

A double-blind randomized placebo-controlled study on the clinical and microbial effects of an essential oil mouth rinse used by patients in supportive periodontal care.

AIM: This 3-month double-blind randomized placebo-controlled study evaluated the clinical and microbial effects of an essential oil mouth rinse used as an adjunct to mechanical plaque control by patients in supportive periodontal care. MATERIAL AND METHODS: Fifty patients were randomly allocated to an essential oil group (Listerine(®) Coolmint; Johnson & Johnson, New Brunswick, NJ, USA) or placebo group to rinse twice per day as an adjunct to mechanical plaque control. At baseline and after 3 months, plaque index (PI), gingivitis index (GI), probing pocket depth, bleeding on probing (BoP) and clinical attachment level were registered. Subgingival plaque samples were collected for the detection and quantification of Aggregatibacter actinomycetemcomitans, Porphyromonas gingivalis, Tannerella forsythia, Treponema denticola, Micromonas micros, Prevotella intermedia, Fusobacterium genus and Streptococcus mutans by means of real-time PCR (qPCR). Patient's compliance, satisfaction and side effects were registered. RESULTS: Twenty-three patients in the essential oil group (mean age: 57) and 21 in the placebo group (mean age: 55) with acceptable oral hygiene at intake (mean PI <1.5 on a scale of 5) adhered to the study protocol. Gingivitis index, PI and BoP significantly reduced over time (P ≤ 0.029); however, between group analyses revealed no significant differences. There was no significant change over time neither in detection frequency nor load for any of the microbiota. Daily rinsing with an essential oil rinse was found safe and perceived beneficial by the patients. CONCLUSION: Patients in supportive periodontal care who are fairly compliant with oral hygiene may not benefit from additional mouth rinsing using an essential oil solution.

Occurrence and antimicrobial susceptibility of Porphyromonas spp. and Fusobacterium spp. in dogs with and without periodontitis.

The occurrence of Porphyromonas gulae, Porphyromonas macacae, Fusobacterium nucleatum and Fusobacterium canifelinum in subgingival plaque from dogs with and without periodontitis as well as their antimicrobial susceptibility were evaluated. From 50 dogs with periodontitis were identified 38 P. gulae, 8 P. macacae, 26 F. nucleatum and 15 F. canifelinum, and from 50 dogs without periodontitis were identified 15 P. gulae, 12 F. nucleatum and 11 F. canifelinum. All strains were susceptible to most of the antibiotics tested, however, different resistance rates to clarithromycin, erythromycin and metronidazole among strains were observed. The role of P. gulae, P. macacae, F. nucleatum and F. canifelinum in periodontal disease of household pets needs to be defined to a better prevention and treatment of the canine periodontitis.

Antimicrobial effect of linalool and α-terpineol against periodontopathic and cariogenic bacteria.

Linalool and α-terpineol exhibited strong antimicrobial activity against periodontopathic and cariogenic bacteria. However, their concentration should be kept below 0.4 mg/ml if they are to be used as components of toothpaste or gargling solution. Moreover, other compounds with antimicrobial activity against periodontopathic and cariogenic bacteria should be used in combination.

In vitro antimicrobial activity of razupenem (SMP-601, PTZ601) against anaerobic bacteria.

We evaluated the in vitro antianaerobic activity of razupenem (SMP-601, PTZ601), a new parenterally administered carbapenem, against 70 reference strains and 323 clinical isolates. Razupenem exhibited broad-spectrum activity against anaerobes, inhibiting most of the reference strains when used at a concentration of ≤1 µg/ml. Furthermore, it exhibited strong activity, comparable to those of other carbapenems (meropenem and doripenem), against clinically isolated non-fragilis Bacteroides spp. (MIC90s of 2 µg/ml), with MIC90 values of 0.06, 0.03, and 0.5 µg/ml against Prevotella spp., Porphyromonas spp., and Fusobacterium spp., respectively. Clinical isolates of anaerobic Gram-positive cocci, Eggerthella spp., and Clostridium spp. were highly susceptible to razupenem (MIC90s, 0.03 to 1 µg/ml).

Epidemiological characteristics of infections caused by Bacteroides, Prevotella and Fusobacterium species: a prospective observational study.

In order to investigate differences among infections due to Gram-negative anaerobic bacteria (Bacteroides, Prevotella and Fusobacterium spp.), clinical, epidemiological, and microbiological data were collected and evaluated from 206 anaerobic infections. The most frequently isolated species was Bacteroides fragilis. The majority of the cases were intra-abdominal infections (49%) followed by skin and soft tissue infections (24.7%). Logistic regression analysis showed that Bacteroides spp. strains were more often isolated from intra-abdominal infections (p = 0.002), whereas Prevotella spp. were isolated more frequently from cases with shorter duration of hospitalization (p = 0.026), and less frequently from bloodstream infections (p = 0.049). In addition, Bacteroides spp. were associated with coinfection due to Enterobacteriaceae species (p = 0.007), whereas Prevotella spp. were associated with coinfection due to Staphylococcus spp. (p = 0.002). Patients with an infection due to B. fragilis, were more frequently admitted in a general surgical ward (p = 0.017), or have been treated with a 2nd generation cephalosporin before anaerobic infection onset (p = 0.05). Total mortality was 10.9% and was associated with bacteremia (p = 0.026), and hematological (p = 0.028), or solid organ malignancy (p = 0.007). Metronidazole resistance was detected only among Prevotella spp. (16.2%) and B. fragilis group (0.8%) isolates. In conclusion, this study indicated differences between infections due to the most frequently isolated Gram-negative anaerobic species, differences that may affect the design and implementation of empirical antimicrobial chemotherapy guidelines.

Association between Faecalibacterium prausnitzii and dietary fibre in colonic fermentation in healthy human subjects.

The intestinal microbiota are a complex ecosystem influencing the immunoregulation of the human host, providing protection from colonising pathogens and producing SCFA as the main energy source of colonocytes. Our objective was to investigate the effect of dietary fibre exclusion and supplementation on the intestinal microbiota and SCFA concentrations. Faecal samples were obtained from healthy volunteers before and after two 14 d periods of consuming formulated diets devoid or supplemented with fibre (14 g/l). The faecal microbiota were analysed using fluorescent in situ hybridisation and SCFA were measured using GLC. There were large and statistically significant reductions in the numbers of the Faecalibacterium prausnitzii (P < or = 0.01) and Roseburia spp. (P < or = 0.01) groups during both the fibre-free and fibre-supplemented diets. Significant and strong positive correlations between the proportion of F. prausnitzii and the proportion of butyrate during both baseline normal diets were found (pre-fibre free r 0.881, P = 0.001; pre-fibre supplemented r 0.844, P = 0.002). A significant correlation was also found between the proportional reduction in F. prausnitzii and the proportional reduction in faecal butyrate during both the fibre-free (r 0.806; P = 0.005) and the fibre-supplemented diet (r 0.749; P = 0.013). These findings may contribute to the understanding of the association between fibre, microbiota and fermentation in health, during enteral nutrition and in disease states such as Crohn's disease.

The Pott's puffy tumor: an unusual complication of frontal sinusitis, methods for its detection.

This is a case report of a Pott's puffy tumor, characterized by a subperiosteal abscess associated with frontal bone osteomyelitis, as a consequence of a frontal sinusitis, in a 15-year-old boy. Pott's puffy tumor is a rare condition usually seen as a complication of frontal sinusitis and more commonly described in children. Given that, superficial temporal artery pseudoaneurysms might be interpreted as a cyst or lipoma, it is imperative that physicians be aware of their presentation.

Comparative evaluation of bactericidal potential of four root canal filling materials against microflora of infected non-vital primary teeth.

BACKGROUND AND OBJECTIVES: Since complete debridement of the root canals of the primary teeth is not practically possible due to the highly variable root canal anatomy, success of the endodontic therapy depends partly on the use ofantibacterial irrigating agents and root canal filling materials. Recent literature indicates that anaerobes comprise a majority of the bacteria in necrotic root canals ofprimary teeth. The study determined the antibacterial effectiveness of four root canal filling materials namely Calcium hydroxide, Zinc oxide eugenol, Vitapex and Metapex against microbial specimens obtained directly from necrotic root canals of primary teeth. METHOD: Microbial specimens were collected using sterile paper points, from 15 primary maxillary and mandibular posterior teeth of randomly selected children in the age group of 4-10 years with infected non vital primary teeth, requiring pulpectomy procedure. The microbial specimens collected were subjected to microbiological analysis and the antimicrobial potential of root canal filling materials were tested using Agar diffusion technique. RESULTS: were statistically analyzed using one-way ANOVA. Facultative/Aerobic organisms were isolated in all the cases, anaerobic organisms were isolated in 80% of the cases, and Candida albicans was isolated in 1 case. ZOE showed superior inhibitory activity against most of the organisms isolated followed by Vitapex, Calcium hydroxide and Metapex in descending order. CONCLUSION: Our data may be useful as a guide for relative antimicrobial effectiveness or non-effectiveness of the materials employed. In vivo studies are required to state the specific antimicrobial activity and merits and demerits of any of the test filling material.

Idiopathic Purulent Pericarditis: A Rare Diagnosis.

BACKGROUND Acute bacterial pericarditis is rare, and the incidence numbers have been declining in the modern antibiotic era. Purulent bacterial pericarditis is a fatal disease in which mortality rates can reach 100% if left untreated. CASE REPORT We present a case of primary purulent bacterial pericarditis with polymicrobial growth including Micromonas micro, Prevotella intermedia and Fusobacterium species, all of which are anaerobic flora of the oral cavity. Constant re-accumulation of the purulent pericardial effusion led the patient to have recurrent echocardiographic and clinical cardiac tamponade requiring recurrent pericardiocentesis' and eventually a pericardial window. CONCLUSIONS Although rare, bacterial pericarditis has been noted to lead to clinical and echocardiographic tamponade. Early diagnosis and treatment are necessary for improving clinical outcomes. It is important to have a suspicion for purulent pericarditis, due to its high level of mortality, in patients who present with non-specific symptoms and pleuritic chest pain.

Recovery of aerobic and anaerobic bacteria from patients with acute appendicitis using blood culture bottles / Recuperación de bacterias aerobias y anaerobias de pacientes con apendicitis aguda mediante botellas de hemocultivo

Introduction: Acute appendicitis is the first cause of acute abdomen, however, there is a little information about the associated bacteria and its sensibility profile. Objetive: To identify and to determine the resistance pattern of aerobic and anaerobic bacteria isolated in periapendicular fluid cultures taken in patients with acute appendicitis and to establish the proportions of isolates according to the clinical phase. Materials and methods: A descriptive and prospective study was undertaken at the Hospital Universitario de San José (Bogotá, Colombia) of patients older than sixteen years of age, undergoing an open appendectomy. A sample of periappendiceal fluid was taken, which was deposited directly into aerobic and anaerobic blood culture bottles. Results: One hundred and fifty-four patients were included. The overall positivity of cultures was 87% (n=1344); 77% (n=118) for aerobes and 51% (n=79) for anaerobes. The proportion of positive cultures was lower in the uncomplicated appendicitis cases as compared to the complicated ones (80% (66/83) vs. 95%(67/71), p = 0.003). The microorganisms isolated most frequently were: Escherichia coli (53%) (n=84); Bacteroides spp. (25%) (n=25); Propionibacterium acnes (21%) (n=21); coagulase negative Staphylococci (17%) (n=27); Enterococcus spp. (11%) (n=15), and Fusobacterium spp. (11%) (n=11). The sensitivity of E. coli to ampicillin/sulbactam was 30%. The sensitivity of Bacteroides spp. to clindamycin and ampicillin/sulbactam was 91%. All anaerobe isolates were sensitive to piperacillin/tazobactam, ertapenem, meropenem and metronidazole. Conclusions: Intraoperative cultures in acute appendicits are relevant in order to determine the local epidemiological pattern and to establish prophylactic and therapeutic antibiotics for this pathology; direct inoculation in blood culture bottles allows a high recovery of microorganisms.

Introduccción. La apendicitis aguda es la primera causa de abdomen agudo; sin embargo, poco se conoce sobre las bacterias asociadas y su perfil de sensibilidad. Objetivo. Identificar y determinar el patrón de resistencia de las bacterias aerobias y anaerobias aisladas en cultivo de líquido periapendicular tomado de los pacientes con apendicitis aguda, y establecer la proporción de bacterias según la fase clínica. Materiales y métodos. Se llevó a cabo un estudio descriptivo y prospectivo en el Hospital Universitario de San José de Bogotá (Colombia), en pacientes mayores de 16 años sometidos a apendicectomía abierta. Se tomaron muestras de líquido periapendicular, las cuales se sembraron directamente en botellas de hemocultivos para aerobios y anaerobios. Resultados. Se incluyeron 154 pacientes. Del total de cultivos, el 87 % (n=134) fueron positivos: 77 % (n=118) para aerobios y 51 % (n=79) para anaerobios. La proporción de cultivos positivos fue inferior en los casos de apendicitis no complicada, en comparación con aquellos de apendicitis complicada (80 % (66/83) Vs. 95 % (67/71); p=0,003). Los microorganismos aislados con mayor frecuencia fueron: Escherichia coli (53 %) (n=84), Bacteroides sp. (25 %) (n=25), Propionibacterium acnes (21 %) (n=21), Staphylococci coagulasa negativo (17 %) (n=27), Enterococcus sp. (10 %) (n=15) y Fusobacterium sp. (11 %) (n=11). La sensibilidad de E. coli a la amplicilina sulbactam fue de 30 %. La sensibilidad de Bacteroides spp. a la clindamicina y la ampicilina sulbactam fue de 91 %. El 100 % de los anaerobios fueron sensibles a piperacilina tazobactam, ertapenem, meropenem y metronidazol. Conclusiones. Los cultivos intraoperatorios son pertinentes en la apendicitis para determinar el patrón epidemiológico local, y establecer los antibióticos profilácticos y terapéuticos para esta enfermedad. Su siembra directa en botellas de hemocultivo permite una gran recuperación de microorganismos.