Corynebacterium Species of the Conjunctiva and Nose: Dominant Species and Species-Related Differences of Antibiotic Susceptibility Profiles.

PURPOSE: Nondiphtherial Corynebacterium species are normal residents of human skin and mucosa, including the conjunctiva and nose, but can cause conjunctivitis and keratitis. Recently, resistance against various classes of antibiotics has been reported in Corynebacterium. The present study investigated the type of species and antibiotic susceptibilities of the conjunctival and nasal Corynebacterium species. METHODS: This study examined 183 strains of Corynebacterium species that were isolated from patients undergoing preoperative examinations for cataract surgery. Species were identified by RNA polymerase ß-subunit-encoding gene (rpoB) sequencing. Antibiotic susceptibility tests were performed by the microdilution method according to the Clinical and Laboratory Standards Institute standard method M45. RESULTS: Corynebacterium macginleyi was the most predominant species (84%; 46 of 55) in the conjunctiva. The 2 major species in the nasal cavity were Corynebacterium accolens and Corynebacterium propinquum (44% and 31%, respectively), followed by Corynebacterium pseudodiphtheriticum (8%), Corynebacterium jeikeium (7%), and C. macginleyi (3%). In contrast to other nasal Corynebacterium species, only C. macginleyi showed a high susceptibility to macrolides. However, among nonconjunctival Corynebacterium species, C. propinquum, was unique in having a high resistance rate to levofloxacin (29%), comparable with that observed in C. macginleyi (36%). Penicillin G and tobramycin showed good susceptibility in almost all strains. CONCLUSIONS: Drug resistance against fluoroquinolones and macrolides was observed in Corynebacterium species, with the antibiotic susceptibility profiles correlating with differences of the species and niche. Nasal and conjunctival Corynebacterium profiles of drug resistance suggest habitat segregation strictly at the species level.

Noninferiority field trial for evaluation of efficacy of ciprofloxacin associated with internal teat sealant as dry-off protocol.

The aim of this study was to compare the efficacy of two dry-off protocols: (a) dry cow therapy using ciprofloxacin hydrochloride 400 mg followed by the administration of an internal teat sealant composed of 4 g of bismuth subnitrate, and (b) a positive control using dry cow therapy with 250 mg cephalonium followed by the administration of 2.6 g bismuth subnitrate internal teat sealant. A total of 578 Holstein cows selected from 7 commercial herds were randomly allocated into two groups at drying off: (a) ciprofloxacin hydrochloride 400 mg (CH) associated with ITS, n = 1112 mammary quarters/296 cows, or (b) positive control (PC) = cephalonium (250 mg) associated with ITS, n = 1058 mammary quarters/282 cows). A total of 1787 out of 2170 mammary quarters (82%) had negative culture at drying off. The microorganisms most frequently isolated at drying off were CNS (5.62%), Strep. uberis (1.9%), Corynebacterium spp. (1.8%), and Staphylococcus aureus (1.01%). A total of 465 mammary quarters experienced new intramammary infections (NIMIs), and the main microorganisms causing NIMI were CNS (21.94%), Strep. uberis (17.2%), and Pseudomonas spp. (9.7%). The CH protocol was not inferior to PC, as the cure risk of mammary quarters CH-treated was at the noninferiority limit. However, the mammary quarters treated by CH protocol had 24% and 31% lower risk of overall NIMI and NIMI caused by major pathogens, respectively, than mammary quarters dried with the PC protocol. In addition, the mammary quarters treated with CH protocol had a lower risk of CM through the first 60 DIM than those treated with PC protocol. Both DCT protocols showed similar odds of microbiological cure, but the CH protocol had greater prevention against NIMI during dry-off period.

Sodium butyrate ameliorates Corynebacterium pseudotuberculosis infection in RAW264.7 macrophages and C57BL/6 mice.

Corynebacterium pseudotuberculosis (CP) infection in livestock has become highly difficult to control. To decrease the incidence of CP infection, the supplementation of feed with non-antibiotic antibacterial substances is a potential approach. The aim of this study was to assess the effects of sodium butyrate (NaB), a potential alternative to antibiotics, on CP infection in RAW264.7 macrophages and C57BL/6 mice. Our data showed that NaB (2 mM) significantly ameliorated CPinfection in RAW264.7 macrophages and decreased the bacterial load in the spleens of infected mice. By real-time PCR, we found that NaB induced significant decreases in zinc-dependent superoxide dismutase (sodC) and tip protein C (spaC) expression in CP from infected-RAW264.7 cells and in phospholipase D (pld) and spaC expression in CP from the spleens of infected mice. NaB treatment significantly up-regulated cathelicidin-related antimicrobial peptide (cramp) expression in spleens of mice infected with CP. Furthermore, NaB alleviated histopathological changes in spleens of CP-infected mice. In conclusion, NaB ameliorated CP infection in RAW264.7 macrophages and C57BL/6 mice, and these effects may be related to the modulation of sodC, spaC, pld, and cramp expression.

Cellulitis and Bacteremia due to Corynebacterium striatum Identified by Matrix-assisted Laser Desorption Ionization-Time of Flight Mass Spectrometry.

Corynebacterium striatum has been described as a pathogen in immunocompromised patients; however, correctly identifying Corynebacterium spp. is often difficult, and cases of cellulitis caused by C. striatum are only rarely reported. We herein describe a case of cellulitis and bacteremia due to C. striatum identified by matrix-assisted laser desorption ionization-time of flight mass spectrometry. Antimicrobial susceptibility testing was performed using the Strepto-Haemo Supplement method, and vancomycin was replaced by a narrow-spectrum oral amoxicillin.

Corynebacterium spp as causative agents of microbial keratitis.

PURPOSE: To report the clinical and microbiological profile of keratitis caused by Corynebacterium spp. METHODS: The medical and microbiology records of 22 patients, who had presented at the L V Prasad Eye Institute, Bhubaneswar, between June 2009 and December 2012, and whose corneal scrapings had yielded significant growth of Corynebacterium spp, were retrospectively reviewed. A detailed ocular examination was performed before the respective corneal scraping was sent for a microbiological work-up. The data collected from each record included age, gender, predisposing factors (ocular and systemic), clinical presentation, management and outcome of treatment. RESULTS: The mean age of the patients was 43.8±24.4 years. Ocular predisposing factor was present in 14 (63.6%) eyes. Surgical intervention was required in 12 (54.5%) patients. In vitro susceptibility (Kirby-Bauer disc diffusion method) results of Corynebacterium spp to vancomycin (17/19, 89.5%), cefazolin (16/20, 80%), chloramphenicol (11/20, 55%), ofloxacin (13/19, 68.4%), ciprofloxacin (10/20, 50%) and gatifloxacin (10/19, 52.6%) were variable. Drug resistance (more than one drug) was seen in nine (40.9%) Corynebacterium isolates, of which, two (22.2%) showed multidrug resistance to three or more classes of antibiotics. CONCLUSIONS: Corynebacteria can cause severe corneal infection requiring surgical intervention.

Clinical features, microbiological profile and treatment outcome of patients with Corynebacterium endophthalmitis: review of a decade from a tertiary eye care centre in southern India.

AIMS: To report the clinical and microbiological profile along with treatment outcome of patients with endophthalmitis caused by Corynebacterium sp. METHODS: This is a retrospective, consecutive, non-comparative case series of patients with culture-proven Corynebacterium endophthalmitis seen between August 2004 and July 2014. RESULTS: Of 5439 patients clinically diagnosed as infective endophthalmitis, vitreous samples were culture positive for bacteria in 1488 (27%). Sixteen patients (1%) were identified as Corynebacterium endophthalmitis. The clinical settings included trauma (n=10), post-cataract surgery (n=5) and post-penetrating keratoplasty (n=1). In 7/16 (44%) patients, the organisms were visualised in direct microscopy. Tested by disc-diffusion method, all isolates were vancomycin sensitive. However, 9 of 10 isolates were resistant to ceftazidime and 5 of 14 isolates were resistant to amikacin. Initial treatment strategies included pars plana vitrectomy with intravitreal antibiotics (vancomycin and amikacin/ceftazidime) injection (n=9) and pars plana lensectomy along with pars plana vitrectomy and intravitreal antibiotics (vancomycin and amikacin/ceftazidime) injection (n=7). Final visual acuity was 20/200 or better in 11 (69%) of 16 patients. CONCLUSIONS: The prevalence of corynebacterial endophthalmitis is low. The organisms are susceptible to vancomycin, and early appropriate treatment results in favourable outcome.

Corynebacterium falsenii bacteremia occurring in an infant on vancomycin therapy.

Corynebacterium falsenii was described in 1998 as a new Corynebacterium species. We give the first detailed description of a clinically significant Corynebacterium falsenii bacteremia occurring in an infant while on vancomycin therapy.

Multiple abscesses caused by Salmonella enterica and Corynebacterium pseudotuberculosis in a dromedary camel.

A rare case of arthritis, peri-arthiritis and pleurits associated with Salmonella enterica and Corynebacterium pseudotuberculosis infection in a dromedary camel is reported. Articular infections caused by Non-typhoidal Salmonella have been exceptionally described in human medicine. To our knowledge, this would be the first description of articular infections associated with Non-thyphoidal Salmonella in other mammals than humans. Possible pathogenesis of the infection is discussed.

[Etiologic role of Corynebacterium non diphtheriae in patients with different pathology].

Bacteriologic examination of 1589 patients showed that, aside from C. diphtheriae, 11% of acute upper respiratory tract infections were caused by other Corynebacterium species. Such bacteria can cause infections of various localizations (bronchitis, pyelonephritis, urethritis, colpitis, dermatitis, arthritis, etc.). C. pseudodiphtheriticum and C. xerosis were isolated from clinical specimens most frequently. Corynebacterium spp. have adhesive, hemolytic, hemagglutinating, and neuraminidase activity; some of them are highly pathogenic. The most virulent, were following species: C. diphtheriae, C. pseudotuberculosis, C. urealyticum, and C. ulcerans. Corynebacterium non diphtheriae were frequently isolated from clinical specimens in association with staphylococci and streptococci. In such cases, factors of pathogenicity and resistance to antibiotics were more pronounced. Strains isolated with association with other bacteria have lost susceptibility to tetracycline, oleandomycin, penicillin, and erythromycin. It is important to be vigilant about bacteria from Corynebacterium genus in clinical settings, and thoroughly study their biologic characteristics, especially in immunocompromised patients.

Corynebacterium urealyticum urinary tract infection in dogs and cats: 7 cases (1996-2003).

OBJECTIVE: To identify clinical features of Corynebacterium urealyticum urinary tract infection in dogs and cats and antimicrobial susceptibility patterns of C urealyticum isolates. DESIGN: Retrospective study. ANIMALS: 5 dogs and 2 cats. PROCEDURE: Medical records of dogs and cats for which C urealyticum was isolated from urine samples were reviewed. Isolates from clinical cases, along with previously lyophilized unsubtyped isolates of Corynebacterium spp collected between 1977 and 1995, were examined and, if subtyped as C urealyticum, tested for antimicrobial susceptibility. RESULTS: Signalment of infected animals was variable. Prior micturition disorders were common, and all animals had signs of lower urinary tract disease at the time C urealyticum infection was diagnosed. Median urine pH was 8.0; WBCs and bacteria were variably seen in urine sediment. In vitro antimicrobial susceptibility testing of 14 C urealyticum isolates revealed that all were susceptible or had intermediate susceptibility to chloramphenicol, tetracycline, and vancomycin and most were susceptible to enrofloxacin. Thickening of the bladder wall and accumulation of sediment were common ultrasonographic findings. Contrast radiography or cystoscopy revealed findings consistent with encrusting cystitis in 3 dogs. Infection resolved in 2 dogs following surgical debridement of bladder plaques and antimicrobial administration. In 2 other dogs and 1 cat treated with antimicrobials, infection with C urealyticum resolved, but urinary tract infection with a different bacterial species developed. CONCLUSIONS AND CLINICAL RELEVANCE: Results suggest that preexisting urinary tract disorders are common in dogs and cats with C urealyticum infection. Treatment with appropriate antimicrobials in combination with surgical debridement might eliminate C urealyticum infection.

Identification of corynebacterium bovis and other coryneforms isolated from bovine mammary glands.

Bovine mastitis remains the most economically important disease in dairy cows. Corynebacterium bovis, a lipid-requiring Corynebacterium spp., is frequently isolated from the milk of infected mammary glands of dairy cows and is associated with reduced milk production. A total of 212 coryneform bacteria isolated from the milk of dairy cows were obtained from mastitis reference laboratories in the United States and Canada. All isolates had been presumptively identified as Corynebacterium bovis based on colony morphology and growth in the presence of butterfat. Preliminary identification of the isolates was based on Gram stain, oxidase, catalase, and growth on unsupplemented trypticase soy agar (TSA), TSA supplemented with 5% sheep blood, and TSA supplemented with 1% Tween 80. Of the 212 isolates tested, 183 were identified as Corynebacterium spp. based on preliminary characteristics. Of the strains misidentified, one was identified as a yeast, two as Bacillus spp., 11 as Enterobacteriaceae, 18 as staphylococci, one as a Streptococcus spp., and one as an Enterococcus spp. Eighty-seven coryneforms were selected for identification to the species level by direct sequencing of the 16S rRNA gene, the Biolog system and the API Coryne system. Fifty strains were identified as C. bovis by 16S rRNA gene similarity studies: the Biolog and API Coryne systems correctly identified 54.0 and 88.0% of these strains, respectively. The other coryneforms were identified as other Corynebacterium spp., Rhodococcus spp., or Microbacterium spp. These data indicate that the coryneform bacteria isolated from bovine mammary glands are a heterogeneous group of organisms. Routine identification of C. bovis should include Gram-stain, cell morphology, catalase production, nitrate reduction, stimulated growth on 1% Tween 80 supplemented media, and beta-galactosidase production as the minimum requirements.

Vancomycin-resistant Corynebacterium species causing prosthetic valve endocarditis successfully treated with imipenem and ciprofloxacin.

Endocarditis caused by a Corynebacterium sp. resistant to vancomycin, penicillin G, erythromycin, gentamicin and rifampicin arose in a 44-year-old woman 4 months after replacement of the mitral valve with a prosthesis. She was successfully treated with a 79-day course of intravenous imipenem and ciprofloxacin and replacement of the prosthesis 48 days after treatment began.

Isolation of Corynebacterium group JK from clinical specimens with a semiselective medium.

A semiselective medium for the detection of multiresistant lipophilic corynebacteria is described. The medium consisted of tryptose agar, supplemented with Tween 80, lecithin, histidine, glycerol, sodium thiosulfate, fosfomycin, ticarcillin, and 5-fluorocytosine. The medium was tentatively called lecithin-Tween medium (LT medium). It promoted mainly the growth of Corynebacterium group JK, which has recently been identified as a cause of serious infection in immunocompromised patients. The application of LT medium to 6,859 routine clinical specimens increased the percentage of Corynebacterium group JK isolation from 0.1 to 1.0%. Although a total of 72 isolates were found in 65 patients, on the basis of clinical criteria only 2 patients were regarded as having an infection with these bacteria. Consequently, Corynebacterium group JK infection can only be diagnosed through a combination of clinical and microbiological findings. In high-risk areas, however, the use of LT medium for surveillance may facilitate the early detection of these potentially dangerous organisms.