Cellulosimicrobium funkei: First Report of Infection in a Nonimmunocompromised Patient and Useful Phenotypic Tests for Differentiation from Cellulosimicrobium cellulans and Cellulosimicrobium terreum

Abstract

Cellulosimicrobium funkei is a rare, opportunistic pathogen. We describe a case of bacteremia and possibly prosthetic valve endocarditis by this organism in a nonimmunocompromised patient. Useful phenotypic tests for differentiating C. funkei from Cellulosimicrobium cellulans and Cellulosimicrobium terreum include motility, raffinose fermentation, glycogen, D-xylose, and methyl-␣-D-glucopyranoside assimilation, and growth at 35°C. CASE REPORTClinical aspects. An 81-year-old male presented to the Casualty Department with a 2-day history of back pain, acute confusion, and fever. He had undergone a Medtronic Mosaic tissue aortic valve replacement for aortic stenosis 7 months before. On examination, he had a temperature of 39°C and looked very unwell. He had no obvious focus of infection, and systemic examination was normal. The patient had two prior admissions to the hospital in the 7 months following his operation. The first was a month after his surgery, when he was admitted to the general intensive care unit with severe pneumonia and pseudomembranous colitis. All five sets of blood cultures taken during this admission were negative, and a transthoracic echocardiogram was reported as normal. Two months after this discharge, he was readmitted and treated for presumed Micrococcus luteus prosthetic valve endocarditis (PVE) with 6 weeks of intravenous flucloxacillin and 2 weeks of gentamicin. Though a transesophageal echocardiogram at the time did not show any vegetation, 2 of 3 blood culture sets grew Micrococcus luteus. During that admission, he also developed a peripherally inserted central catheter (PICC) line infection with Bacillus cereus, which was treated by line removal.One set of blood cultures was taken before patient therapy of intravenous amoxicillin-clavulanic acid at 1.2 g three times a day (TDS) commenced. After 24 h of incubation, the aerobic bottle in the blood culture set grew Gram-positive rods. Since the patient was improving clinically and a subsequent repeat blood culture was negative, it was presumed that the organism was a skin contaminant. No further identification was carried out, and the isolate was discarded. A transthoracic echocardiogram found no vegetations on the heart valves. No evidence of infection on a chest radiograph, abdominal ultrasound examination, computed tomography (CT) of the brain, magnetic resonance imaging (MRI) of the spine, or a bone scan was found. The patient received 10 days of antibiotics, during which time significant clinical improvement was noted, although his white cell count and C-reactive protein (CRP) level remained persistently elevated.Eighteen days later, the patient developed a fever with an increasing white cell count and CRP level. Three sets of blood cultures were taken. The next day, all six bottles were positive for a Gram-positive rod. Empirical treatment for presumed prosthetic valve endocarditis was started, with intravenous vancomycin at 1 g daily and gentamicin at 80 mg twice a day (BID). An urgent transesophageal echocardiogram confirmed the...

Diversity, Bioactivity and Drug Development of Cultivable Actinobacteria in Six Species of Bird Feces

“…Like Cellulosimicrobium funkei, first discovered in the clinical, was an opportunistic pathogen, close to Oerskovia in taxonomy and mainly infected people who have immune dysfunction or inflammation [20][21], was found in this study, too. Therefore the fresh fecal samples have to be collected from health bodies.…”

A novel strain of Cellulosimicrobium funkei can biologically detoxify aflatoxin B1 in ducklings

“…Although C. funkei has showed potent AFB1 biodegradation capability and safety in vivo study, directly using this microbe as a feed additive seems challenged by the fact that C. funkei is an opportunistic pathogen (Petkar et al, 2011). Therefore, our ongoing research was focus in two directions: (i) exploring the mechanism of AFB1 biodegradation by C. funkei, which try to separate the enzyme and/or other active ingredients such as cell wall that could biodegradation the AFB1 and (ii) using C. funkei alone or with other microbial to do the solid-state fermentation on rapeseed meal and cottonseed meal to improve crude fiber digestibility, reduce AFB1 contents and produce AFB1 biodegradation active ingredients in these feedstuffs.…”

Identification of non-Listeria spp. bacterial isolates yielding a β-d-glucosidase-positive phenotype on Agar Listeria according to Ottaviani and Agosti (ALOA)

“…The third member of the genus Cellulosimicrobium, C. terreum does not grow above 35°C, and, being not that closely genetically related with the other two species, it can be differentiated from C. cellulans and C. funkei based on 16S rRNA sequencing (Yoon et al, 2007). C. cellulans and C. funkei, however, cannot be reliably distinguished by 16S rRNA sequencing and commercially available biochemical identification systems do not reflect recent changes in taxonomy of the genus (Petkar et al, 2011). However, one of the distinguishing characteristics is motility, with C. funkei being motile (as were all isolates in our study, Table 1) and C. cellulans being non-motile (Brown et al, 2006).…”