Three strains of coryneform rods isolated from clinical samples and one of environmental origin exhibited phenotypic and chemotaxonomic properties characteristic of the genus Brevibacterium and their 16S rRNA gene sequences were closely related (98?5-99?0 %) to that of Brevibacterium otitidis. However, DNA-DNA hybridization of one strain (CF87 T ) showed only 59?6 % relatedness to the type strain of B. otitidis, DSM 10718 T , and 75-82 % relatedness to the three other strains. The four strains could be differentiated from B. otitidis by cellular fatty acid composition and some phenotypic characteristics. These findings suggest that the four strains belong to a novel species, for which the name Brevibacterium lutescens sp. nov. is proposed. The type strain of B. lutescens is CF87T (=DSM 15022Recently, a coryneform bacterium belonging to the genus Brevibacterium was reported as a cause of peritonitis in a patient undergoing continuous ambulatory peritoneal dialysis (Wauters et al., 2000b). Its conventional phenotypic characteristics were consistent with those of Brevibacterium otitidis, and 16S rRNA gene sequencing revealed 98?8 % similarity to the sequence of the type strain of that species, which was rather low, but compatible with membership of the same species (Stackebrandt & Goebel, 1994). Later, three B. otitidis-like strains were collected that exhibited a mean of 98?8 % similarity to B. otitidis in their 16S rRNA sequences, two from clinical samples and one from the environment. They were studied more extensively along with the peritonitis strain. A few phenotypic characteristics and DNA-DNA hybridization results clearly indicated that the four strains, including the peritonitis strain, belonged to a novel species, closely related to but distinct from B. otitidis, for which the name Brevibacterium lutescens sp. nov. is proposed.The four novel strains were of human and environmental origin. Strain CF87 T was isolated from peritoneal fluid (Wauters et al., 2000b), strain CF32 from an infected ear discharge, strain CF60 from a peritoneal dialysate fluid and strain CF100 from a peptone preparation. They were stored in glycerol at 220 u C and cultured on blood agar at 37 u C in air for the purposes of this study. T , DSM 13658, DSM 13659 and DSM 13660. In addition, the following clinical isolates from our collection were included in the study: one B. otitidis strain (CF65), confirmed by 16S rRNA gene sequencing and by DNA-DNA hybridization, and eight B. casei and seven B. paucivorans strains, all of them confirmed by 16S rRNA gene sequencing.Most phenotypic characteristics were studied as described previously (Funke et al., 1997;Wauters et al., 1998Wauters et al., , 2000aWauters et al., , 2001. Pyrrolidonyl arylamidase, a-glucosidase and N-acetylb-D-glucosaminidase were tested using diagnostic tablets (Rosco). Assimilation/alkalinization of c-aminobutyric acid was tested using Simmons' citrate agar, replacing citrate by 0?1 % (w/v) of the substrate. Acid production from phenylacetate was examined as follows...

Four identification tests, proposed in addition to conventional methods, were evaluated with 320 fermentative nonlipophilicCorynebacterium strains: growth at 20°C, glucose fermentation at 42°C, alkalinization of sodium formate, and acid production from ethylene glycol. These tests were highly discriminant.Corynebacterium amycolatum displayed a unique profile, allowing it to be distinguished from similar species, such as C. xerosis, C. striatum, and C. minutissimum.

A total of 38 strains of Corynebacterium Group D2 isolated from clinical specimens in Belgian laboratories were characterized by pronounced urease activity, inability to acidify sugars and to reduce nitrates and multiresistance to antibiotics. Two strains were involved in clinical diseases. The organisms were found to have a more opportunistic than pathogenic behaviour.

Propionic acid producing strains of Corynebacterium minutissimum were isolated from three patients with opportunistic infections. One neutropenic patient was undergoing chemotherapy for prolymphocytic leukemia; the other two patients were undergoing hemodialysis and peritoneal dialysis respectively. An unusual feature of these three strains was their resistance to several antibiotics, which is seldom seen in diphtheroids other than Corynebacterium jeikeium and CDC group D2.

During the last few years, the taxonomic studies of corynebacteria and coryneform organisms have been improving constantly. This has led to a better understanding of the pathogenic role of these bacteria, which primarily cause infection in hospitalized patients with immunosuppression or artificial devices. Corynebacterium jeikeium and Corynebacterium amycolatum are the two species most frequently isolated from clinical samples [1], but other new species are also found in clinical specimens. We report here a case of chronic osteomyelitis in which two recently described coryneform organisms, Dermabacter hominis and Actinomyces neuii subsp. neuii, were isolated.As a result of a fall, a 76-year-old male patient presented with a fracture of the calcaneum and avulsion of the base of the Achilles' tendon without a breach of the skin. He was treated by orthopedic reduction of the fracture, osteosynthesis and immobilization. Soon after, an infection due to Enterobacter cloacae was detected. During the following 4-year period, and despite three superficial curettages of the lesion, the seat of osteosynthesis showed fistulization and a lasting flow. The area was not painful, but it repeatedly became infected, causing discomfort to the patient. Finally, the patient was referred to our institution for surgical advice.After surgical curettage of the spongy tissue in the posterior part of the calcaneum, a purulent collection with bone deposits was found. There was no artificial material, since resorbable wire had been used in the previous interventions. The bone deposits were removed and sent for laboratory examination. On anatomo-pathological examination, the dermis showed a fibro-cicatricial and fibro-inflammatory change. The bone deposit was composed of empty trabeculae mixed with inflammatory scales and bacterial cells. On bacteriological examination, the coryneform bacilli Dermabacter hominis and Actinomyces neuii subsp. neuii were isolated, but no mycobacteria and no anaerobes were found. After inserting a drainage tube and administering antibiotherapy (2 g cefazolin daily) for 11 weeks, the inflammatory parameters normalized and clinical healing was recorded. At 4-year follow-up, the patient was considered clinically cured.Although Gram stains of the wound samples were not informative, the presence of gram-positive bacilli was noted in the bone deposits. From both the wound and the bone deposit samples, two types of gram-positive bacilli grew on sheep blood agar.Extensive bacteriological examination of the first isolate gave the following results: small, gram-positive, slightly pleomorphic coryneform bacilli, facultatively anaerobic, growing on blood agar with whitish, alphahemolytic colonies with entire edges and no particular smell. Catalase was positive. Glucose fermentation resulted in large amounts of lactic and succinic acids as end-products. Acid was produced from glucose, sucrose, maltose, mannitol and xylose. Urease was negative, and neither aesculin nor gelatin were hydrolyzed. Nitrate reduction and pyrazinamid...