BACKGROUND:In previous studies, Propionibacterium acnes was cultured from intervertebral disc tissue of ~25% of patients undergoing microdiscectomy, suggesting a possible link between chronic bacterial infection and disc degeneration. However, given the prominence of P. acnes as a skin commensal, such analyses often struggled to exclude the alternate possibility that these organisms represent perioperative microbiologic contamination. This investigation seeks to validate P. acnes prevalence in resected disc cultures, while providing microscopic evidence of P. acnes biofilm in the intervertebral discs. METHODS:Specimens from 368 patients undergoing microdiscectomy for disc herniation were divided into several fragments, one being homogenized, subjected to quantitative anaerobic culture, and assessed for bacterial growth, and a second fragment frozen for additional analyses. Colonies were identified by MALDI-TOF mass spectrometry and P. acnes phylotyping was conducted by multiplex PCR. For a sub-set of specimens, bacteria localization within the disc was assessed by microscopy using confocal laser scanning and FISH. RESULTS:Bacteria were cultured from 162 discs (44%), including 119 cases (32.3%) with P. acnes. In 89 cases, P. acnes was cultured exclusively; in 30 cases, it was isolated in combination with other bacteria (primarily coagulase-negative Staphylococcus spp.) Among positive specimens, the median P. acnes bacterial burden was 350 CFU/g (12 - ~20,000 CFU/g). Thirty-eight P. acnes isolates were subjected to molecular sub-typing, identifying 4 of 6 defined phylogroups: IA1, IB, IC, and II. Eight culture-positive specimens were evaluated by fluorescence microscopy and revealed P. acnes in situ. Notably, these bacteria demonstrated a biofilm distribution within the disc matrix. P. acnes bacteria were more prevalent in males than females (39% vs. 23%, p = 0.0013). CONCLUSIONS:This study confirms that P. acnes is prevalent in herniated disc tissue. Moreover, it provides the first visual evidence of P. acnes biofilms within such specimens, consistent with infection rather than microbiologic contamination.

BACKGROUND:Infantile myofibromatosis belongs to a family of soft tissue tumors. The majority of these tumors have benign behavior but resistant and malignant courses are known, namely in tumors with visceral involvement. The standard of care is surgical resection. Observations suggest that low dose chemotherapy is beneficial. The treatment of resistant or relapsed patients with multifocal disease remains challenging. Patients that harbor an actionable mutation in the kinase domain are potential subjects for targeted tyrosine kinase inhibitor therapy.CASE PRESENTATION:An infant boy with inborn generalized infantile myofibromatosis that included bone, intracranial, soft tissue and visceral involvement was treated according to recent recommendations with low dose chemotherapy. The presence of a partial but temporary response led to a second line of treatment with six cycles of chemotherapy, which achieved a partial response again but was followed by severe toxicity. The generalized progression of the disease was observed later. Genetic analyses were performed and revealed a PDGFRB gene c.1681C>A missense heterozygous germline mutation, high PDGFRβ phosphokinase activity within the tumor and the heterozygous germline Slavic Nijmegen breakage syndrome 657del5 mutation in the NBN gene. Targeted treatment with sunitinib, the PDGFRβ inhibitor, plus low dose vinblastine led to an unexpected and durable response without toxicities or limitations to daily life activities. The presence of the Slavic NBN gene mutation limited standard chemotherapy dosing due to severe toxicities. Sister of the patient suffred from skull base tumor with same genotype and histology. The same targeted therapy led to similar quick and durable response.CONCLUSION:Progressive and resistant incurable infantile myofibromatosis can be successfully treated with the new approach described herein. Detailed insights into the biology of the patient's tumor and genome are necessary to understand the mechanisms of activity of less toxic and effective drugs except for up to date population-based chemotherapy regimens.

Background The relationship between intervertebral disc degeneration and chronic infection by Propionibacterium acnes is controversial with contradictory evidence available in the literature. Previous studies investigating these relationships were under-powered and fraught with methodical differences; moreover, they have not taken into consideration P. acnes’ ability to form biofilms or attempted to quantitate the bioburden with regard to determining bacterial counts/genome equivalents as criteria to differentiate true infection from contamination. The aim of this prospective cross-sectional study was to determine the prevalence of P. acnes in patients undergoing lumbar disc microdiscectomy. Methods and Findings The sample consisted of 290 adult patients undergoing lumbar microdiscectomy for symptomatic lumbar disc herniation. An intraoperative biopsy and pre-operative clinical data were taken in all cases. One biopsy fragment was homogenized and used for quantitative anaerobic culture and a second was frozen and used for real-time PCR-based quantification of P. acnes genomes. P. acnes was identified in 115 cases (40%), coagulase-negative staphylococci in 31 cases (11%) and alpha-hemolytic streptococci in 8 cases (3%). P. acnes counts ranged from 100 to 9000 CFU/ml with a median of 400 CFU/ml. The prevalence of intervertebral discs with abundant P. acnes (≥ 1x103 CFU/ml) was 11% (39 cases). There was significant correlation between the bacterial counts obtained by culture and the number of P. acnes genomes detected by real-time PCR (r = 0.4363, p<0.0001). Conclusions In a large series of patients, the prevalence of discs with abundant P. acnes was 11%. We believe, disc tissue homogenization releases P. acnes from the biofilm so that they can then potentially be cultured, reducing the rate of false-negative cultures. Further, quantification study revealing significant bioburden based on both culture and real-time PCR minimize the likelihood that observed findings are due to contamination and supports the hypothesis P. acnes acts as a pathogen in these cases of degenerative disc disease.

Jaglic Z., Cervinkova D., Vlkova H., Michu E., Kunova G., Babak V. (2012): Bacterial biofilms resist oxidising agents due to the presence of organic matter. Czech J. Food Sci., 30: 178–187. This study evaluated the susceptibility of planktonic and biofilm cells of Staphylococcus spp. (n = 87), klebsiella spp. (n = 30), and escherichia coli (n = 74) isolates originating from food contact surfaces of milk and meat processing plants to benzalkonium chloride (BAC), sodium hypochlorite (NaClO), chloramine B (CAB), and peracetic acid (PAA). Bacterial growth and reduction of viable cells in the presence of disinfectants were determined in tryptone soya broth (TSB) and water, respectively. Biofilm positive isolates ( n = 73) were tested for the presence of selected qac genes. Unlike BAC, chlorine‑based disinfectants and PAA were poorly efficient in TSB, especially in the case of biofilms. However, when tested in water, the efficacy of NaClO, CAB and PAA substantially increased, which was particularly evident in biofilms. In water, staphylococcal biofilms were even more susceptible to CAB than planktonic cells. A part (23.3%) of the biofilm positive staphylococci carried the qac genes but did not express an increased resistance to BAC. This study showed that bacterial biofilms protected with organic matter could be one of the main reasons for disinfection failure.

The adherence of microorganisms to surfaces is a critical precondition for biofilm development. In this study, we evaluated the adherence (in amounts capable of biofilm formation) of Staphylococcus epidermidis in milk to stainless steel. During a 6-h time frame, the effect of milk temperature and laminar flow on adherence was analysed. In amounts capable of biofilm formation, the cells adhered within 0.5 h; however, at the milk temperatures promoting cell growth (25 and 28 °C), the cells proceeded to detach from the surface when bacteria started to grow (after 2 h), but only during the milk flow. When the temperatures were below the growth limit (6 and 22 °C) or under static conditions, the cells remained attached during the whole monitoring period. This study showed that temperatures which are suboptimal for growth and static conditions support the adhesion S. epidermidis in amounts capable of biofilm formation. On the contrary, at temperatures allowing the growth, adhered cells of S. epidermidis can easily be washed away from the stainless steel surface when bacteria begin to grow.

Staphylococcus epidermidis may form biofilms in milk processing plants and secondarily contaminate milk products. In this study, the ability of S. epidermidis to form a biofilm in milk and the influence of glucose and NaCl on biofilm formation were analysed. Biofilm production on stainless steel was investigated at 30°C in pasteurized milk and in milk containing glucose, NaCl or both glucose and NaCl. Biofilm formation was evaluated by monitoring of colony-forming units (cfu) on stainless chips and by real-time quantitative PCR analysis of the icaA and σB transcripts. An increase in cfu and icaA transcription was observed after 20h incubation, especially in milk containing glucose and NaCl. NaCl alone was shown to present a greater risk of biofilm development in milk than glucose alone, but the NaCl/glucose combination represented the highest risk. The σB factor did not seem to be involved in biofilm formation under the conditions of this study.