Pitted keratolysis.

Pitted keratolysis (PK) is a common superficial bacterial skin infection confined to the stratum corneum. It is clinically characterized by multifocal, discrete, pits or crater-like punched-out lesions, commonly over the pressure-bearing aspects of the foot. It is asymptomatic and associated with malodour. The surface is often moist and macerated. The diagnosis of PK is often clinical and diagnostic procedures are usually unnecessary. Lifestyle modifications form the cornerstone of the management of PK. It responds well to topical antimicrobials.

Clinico-pathological responses and PCR detection of Corynebacterium pseudotuberculosis and its immunogenic mycolic acid extract in the vital organs of goats.

Caseous lymphadenitis is an infectious disease of almost all animals, particularly small ruminants that are caused by Corynebacterium pseudotuberculosis. The organism causes the formation of suppurative abscesses in superficial and visceral lymph nodes and in visceral organs. This current study was designed to elucidate the clinicopathological responses and PCR detection of the aetiological agent in the vital organs of goats challenged with C. pseudotuberculosis and its immunogenic mycolic acid extract. A total of twelve clinically healthy crossbred Boer female goats were divided into three groups: A, B, and C (four goats per group). Group A was inoculated intradermally with 2 ml of sterile phosphate buffered saline (PBS) pH 7 as a control group. Group B was inoculated intradermally with 2 ml of mycolic acid extract (1 g/ml), while group C was inoculated intradermally with 2 ml of 109 colony-forming unit (cfu) of live C. pseudotuberculosis. The experimental animals were observed for clinical responses for 90 days post-inoculation and the clinical signs were scored according to the severity. The clinical signs observed in this study were temperature, heart rate, respiratory rate, rumen motility, enlargement of lymph nodes, and body condition score. The experimental animals were euthanised and tissue samples from different anatomical regions of the vital organs were collected in 10% buffered formalin, processed, sectioned, and stained with H&E. Results of both C. pseudotuberculosis and mycolic acid treated groups indicated a significant difference (p < 0.05) in body temperature. Group C showed a significant increase in temperature (p < 0.05) at week 1 (39.59 ±â€¯0.29 °C), week 2 (39.67 ±â€¯0.27 °C) and week 3 (40.22 ±â€¯0.15 °C). Whereas group B showed a significant increase in temperature (p < 0.05) only at week 1 (39.36 ±â€¯0.14 °C). Heart rate in group C showed a significant increase between week 1 (93.35 ±â€¯0.42 bpm) and week 11 (86.52 ±â€¯1.32 bpm), and the mean heart rate of group B showed a significant increase (p < 0.05) between week 1 (89.90 ±â€¯0.60 bpm) and week 9 (86.90 ±â€¯0.99 bpm). Group C showed a significant increase of respiratory rate (p < 0.05) at week 1 (36.85 ±â€¯0.14 bpm), week 2 (36.90 ±â€¯0.62), week 3 (30.80 ±â€¯1.97 bpm), and week 4 (34.85 ±â€¯1.19 bpm). The mean of the respiratory rate of group B only increased at week 1 (32.98 ±â€¯1.30 bpm) and week 2 (31.87 ±â€¯0.48 bpm). Both groups C & B showed significant decreases in rumen motility and body condition score as compared to the control. The histopathological changes were significant in group C, this was shown by mild to severe haemorrhage, congestion, degeneration and necrosis, oedema, infiltration with inflammatory cells mainly lymphocytes and macrophages, while group B was less affected and showed mild to moderate haemorrhage, congestion, degeneration and necrosis, infiltration of inflammatory cells and oedema as compared to the control group. This study concluded that C. pseudotuberculosis caused typical CLA disease with a short incubation period in the experiment. While the mycolic acid extracted from C. pseudotuberculosis caused mild clinical signs, no abscess formation, and negative PCR result. Moreover, evidence of mild to moderate histopathological changes in vital organs was also observed.

Virulence potential of Corynebacterium striatum towards Caenorhabditis elegans.

Corynebacterium striatum strains have been increasingly reported as etiological agents of nosocomial infections and outbreaks in industrialized and developing countries. However, there are few studies focused on the virulence potential of C. striatum. A growing body of research supports the use of Caenorhabditis elegans as a model host for investigating the virulence potential of pathogenic bacteria, including corynebacteria. In the present study, chemotaxis behaviour, mortality, and morphological changes were investigated in nematodes infected by four C. striatum strains isolated from different clinical sites, and with different MDR profiles and PFGE types. The results showed chemotaxis of nematodes towards C. striatum. Nematode death (> 60%) was detected from the first day post-infection with all strains tested, but at different levels, independent of biofilm formation on catheter surfaces and differences in growth temperature between nematodes (20 °C) and mammals (37 °C). C. striatum 2369/II multidrug-resistant (MDR; from tracheal aspirate of a patient undergoing endotracheal intubation) and 1961/III multidrug-sensitive (MDS; urine) strains led to 100% mortality in worms. Survival of nematodes was observed until 4 days post-infection with the C. striatum 1954/IV MDS strain isolated from a surgical wound (13%) and 1987/I MDR strain isolated from a patient with a lower respiratory tract infection (39%). The Dar phenotype was observed post-infection with all MDS and MDR strains except 1954/IV. All strains showed the capacity for bagging formation. Star formation was observed only with strains that led to 100% nematode mortality. In conclusion, C. striatum was found to exert virulence for C. elegans. Variations in nematode morphological changes and levels of mortality indicate differences in the virulence potential of C. striatum independent of clinical isolation site, capacity for biofilm formation, and MDR and PFGE profiles.

Induction of Necrosis in Human Macrophage Cell Lines by Corynebacterium diphtheriae and Corynebacterium ulcerans Strains Isolated from Fatal Cases of Systemic Infections.

When infecting a human host, Corynebacterium diphtheriae and Corynebacterium ulcerans are able to impair macrophage maturation and induce cell death. However, the underlying molecular mechanisms are not well understood. As a framework for this project, a combination of fluorescence microscopy, cytotoxicity assays, live cell imaging, and fluorescence-activated cell sorting was applied to understand the pathogenicity of two Corynebacterium strains isolated from fatal cases of systemic infections. The results showed a clear cytotoxic effect of the bacteria. The observed survival of the pathogens in macrophages and, subsequent, necrotic lysis of cells may be mechanisms explaining dissemination of C. diphtheriae and C. ulcerans to distant organs in the body.

Correlation between nasal microbiome composition and remote purulent skin and soft tissue infections.

The incidence of skin and soft tissue infections (SSTIs) has increased dramatically over the past decade, resulting in significant morbidity in millions of otherwise healthy individuals worldwide. Certain groups, like military personnel, are at increased risk for SSTI development. Although nasal colonization with Staphylococcus aureus is an important risk factor for the development of SSTIs, it is not clear why some colonized individuals develop disease while others do not. Recent studies have revealed the importance of microbial diversity in human health. Therefore, we hypothesized that the nasal microbiome may provide valuable insight into SSTI development. To examine this hypothesis, we obtained anterior-naris samples from military trainees with cutaneous abscesses and from asymptomatic (non-SSTI) participants. We also obtained samples from within abscess cavities. Specimens were analyzed by culture, and the microbial community within each sample was characterized using a 16S sequencing-based approach. We collected specimens from 46 non-SSTI participants and from 40 participants with abscesses. We observed a significantly higher abundance of Proteobacteria in the anterior nares in non-SSTI participants (P < 0.0001) than in participants with abscesses. Additionally, we noted a significant inverse correlation between Corynebacterium spp. and S. aureus (P = 0.0001). The sensitivity of standard microbiological culture for abscesses was 71.4%. These data expand our knowledge of the complexity of the nasal and abscess microbiomes and potentially pave the way for novel therapeutic and prophylactic countermeasures against SSTI.

Molecular and epidemiological review of toxigenic diphtheria infections in England between 2007 and 2013.

Human infections caused by toxigenic corynebacteria occur sporadically across Europe. In this report, we undertook the epidemiological and molecular characterization of all toxigenic corynebacterium strains isolated in England between January 2007 and December 2013. Epidemiological aspects include case demographics, risk factors, clinical presentation, treatment, and outcome. Molecular characterization was performed using multilocus sequence typing (MLST) alongside traditional phenotypic methods. In total, there were 20 cases of toxigenic corynebacteria; 12 (60.0%) were caused by Corynebacterium ulcerans, where animal contact was the predominant risk factor. The remaining eight (40.0%) were caused by Corynebacterium diphtheriae strains; six were biovar mitis, which were associated with recent travel abroad. Adults 45 years and older were particularly affected (55.0%; 11/20), and typical symptoms included sore throat and fever. Respiratory diphtheria with the absence of a pharyngeal membrane was the most common presentation (50.0%; 10/20). None of the eight C. diphtheriae cases were fully immunized. Diphtheria antitoxin was issued in two (9.5%) cases; both survived. Two (9.5%) cases died, one due to a C. diphtheriae infection and one due to C. ulcerans. MLST demonstrated that the majority (87.5%; 7/8) of C. diphtheriae strains represented new sequence types (STs). By adapting several primer sequences, the MLST genes in C. ulcerans were also amplified, thereby providing the basis for extension of the MLST scheme, which is currently restricted to C. diphtheriae. Despite high population immunity, occasional toxigenic corynebacterium strains are identified in England and continued surveillance is required.

Contact Lens-Related Infectious Keratitis with White Plaque Formation Caused by Corynebacterium propinquum.

We report the first case of Corynebacterium propinquum keratitis in the compromised cornea of a diabetic patient wearing therapeutic contact lenses. The strain was identified to the species level based on sequencing of the 16S rRNA gene and RNA polymerase ß-subunit-encoding gene (rpoB). Ophthalmologists should be aware of nondiphtherial corynebacterial infection of compromised corneas.

Early prosthetic valve endocarditis caused by Corynebacterium kroppenstedtii.

Corynebacterium (C.) kroppenstedtii is a rarely detected agent of bacterial infections in humans. Here, we describe the first case of prosthetic valve endocarditis caused by C. kroppenstedtii. Application of molecular methods using surgically excised valve tissue was a cornerstone for the establishment of the microbiological diagnosis, which is crucial for targeted antimicrobial treatment.

MAPK involvement in cytokine production in response to Corynebacterium pseudotuberculosis infection.

BACKGROUND: Caseous lymphadenitis (CL) is a contagious infectious disease of small ruminants caused by Corynebacterium pseudotuberculosis. Is characterized by the formation of abscesses in the lymph nodes and intestines of infected animals, induced by inflammatory cytokines. The production of cytokines, such as IL-10, TNF-α, IL-4 and IFN-γ, is regulated by mitogen-activated protein kinase (MAPK) pathway activation. The present study investigated the involvement of MAPK pathways (MAPK p38, ERK 1 and ERK 2) with respect to the production of cytokines induced by antigens secreted by C. pseudotuberculosis over a 60-day course of infection. CBA mice (n = 25) were divided into three groups and infected with 102 colony forming units (CFU) of attenuated strain T1, 102 CFU of virulent strain VD57 or sterile saline solution and euthanized after 30 or 60 days. Murine splenocytes were treated with specific inhibitors (MAPK p38 inhibitor, ERK 1/2 inhibitor or ERK 2 inhibitor) and cultured with secreted antigens obtained from pathogenic bacteria (SeT1 or SeVD57). RESULTS: The MAPK pathways evaluated were observed to be involved in the production of IL-10, under stimulation by secreted antigens, while the MAPK p38 and ERK 1 pathways were shown to be primarily involved in TNF-α production. By contrast, no involvement of the MAPK p38 and ERK 1 and 2 pathways was observed in IFN-γ production, while the ERK 2 pathway demonstrated involvement in IL-4 production only in the mouse splenocytes infected with VD57 under stimulation by SeT1. CONCLUSION: The authors hypothesize that MAPK p38 and ERK 1 pathways with respect to TNF-α production, as well as the MAPK p38 and ERK 1 and 2 pathways in relation to IL-10 production under infection by C. pseudotuberculosis are important regulators of cellular response. Additionally, the lack of the MAPK p38 and ERK 1/2 pathways in IFN-γ production in infected CBA murine cells stimulated with the two secreted/excreted antigens, in IL-4 production showing involvement only via the ERK 2 pathway under stimulation by SeT1 antigen during 60-day infection period with the virulent strain, suggests that these pathways regulated the production of pro-inflammatory and regulatory cytokines in the splenic cells of CBA mice.

Corynebacterium minutissimum vascular graft infection: case report and review of 281 cases of prosthetic device-related Corynebacterium infection.

Corynebacterium spp. have proven their pathogenic potential in causing infections, particularly in the setting of immunosuppression and prosthetic devices. We conducted a PubMed literature review of all cases of Corynebacterium prosthetic device infections published in the English language through December 2013. The majority of cases involved peritoneal dialysis and central venous catheters, but prosthetic joints and central nervous system shunts/drains were also involved. The management of these cases in terms of retention or removal of the device was not uniform; however, the overall mortality remained the same among both groups. All of these prosthetic device infections pose potential problems in management when the device cannot be removed safely for the patient, especially with the lack of data on the pathogenicity of Corynebacterium species. However with better identification of species and sensitivities, successful treatment is possible even with retention of the device.

Clinicopathological studies on ulcerative lymphangitis in cattle: Alterations in serum inflammatory cytokines, anti-microbial, organs functions, and oxidative stress-related biomarkers.

Background: Affection with Corynebacterium pseudotuberculosis (C. pseudotuberculosis) and development of cellulitis and/or abscess formation with cutaneous lymphangitis in cattle is rare to some extent, so literature about the biochemical changes that would accompany this infection is rare. Aim: In this context, the present study was designed to screen the effect of the infection with C. pseudotuberculosis cutaneous lymphangitis on the release of some immune molecules, organ functions, and redox state in Baladi cows. Methods: Fourteen Baladi cows from a small dairy farm in El-Behira, Egypt, were selected to complete this study. After bacteriological culture confirmation, seven of them were found suffering from cutaneous lesions due to infection with C. pseudotuberculosis (Diseased group), while the others were healthy (Healthy group). Serum samples were obtained to evaluate the presumptive changes in some clinicopathological parameters. Results: Serum analysis revealed a significant decrease in the levels of interferon-gamma and interleukin-17 as well as a significant decrement in the concentration of beta-defensin (ß-defensin) and lipocalin-2. While serum level of interleukin-10 recorded a significant increase in these animals when compared to healthy control animals. Concurrently, the affected animals recorded a significant elevation in serum levels of hepato-cardiac enzymes, urea, and creatinine in addition to disturbance in the serum redox state. Conclusion: In conclusion, infection with C. pseudotuberculosis cattle may disturb the defensive immune state, body organ function, and redox state of the animals.

Clinicopathological investigation on caseous lymphadenitis in local breed sheep in Algeria.

This study was carried out of 4,419 animals raised in an extensive system on local breed sheep of the Tiaret region during 2 years (2010-2011) to determine some clinical and pathological aspects associated to caseous lymphadenitis (CL). Clinical examination revealed a prevalence rate of 5.7 %. CL prevalence rate was significantly higher in females (6 %) than in males (4.8 %). The most affected superficial lymph nodes were mandibular lymph nodes (46.1 %). Gross examination of 1,679 carcasses of sheep at the abattoir revealed the presence of abscesses on 250 carcasses (14.9 %). Out of 105 cases showing lesions of CL, Corynebacterium pseudotuberculosis (53.6 %) was isolated as mixed infection with Staphylococcus aureus (43 %) and Escherechia coli (17.9 %). CL prevalence was significantly higher in adult than in young sheep and in female than in male ones. Visceral form of CL was associated to "thin ewe syndrome" responsible for significant economic losses in Algeria.

Bloodstream infection caused by nontoxigenic Corynebacterium diphtheriae in an immunocompromised host in the United States.

Corynebacterium species are well-known causes of catheter-related bloodstream infections. Toxigenic strains of Corynebacterium diphtheriae cause respiratory diphtheria. We report a bloodstream infection caused by a nontoxigenic strain of C. diphtheriae and discuss the epidemiology, possible sources of the infection, and the implications of rapid species identification of corynebacteria.

Corynebacterium tuberculostearicum: a potentially misidentified and multiresistant Corynebacterium species isolated from clinical specimens.

Corynebacterium tuberculostearicum is a lipophilic corynebacterium validly characterized in 2004. We provide clinical information on 18 patients from whom this organism was isolated. The majority of the patients were hospitalized and had a history of prolonged treatment with broad-spectrum antimicrobials. In 7 (38.9%) of the 18 cases, the isolates were found to be clinically relevant. The present report also includes detailed data on the biochemical and molecular identification of C. tuberculostearicum, as well as its identification by matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS). Our data demonstrate that routine biochemical tests do not provide reliable identification of C. tuberculostearicum. MALDI-TOF MS represents a helpful tool for the identification of this species, since all of the strains matched C. tuberculostearicum as the first choice and 58.3% (7/12) of the strains processed with the full extraction protocol generated scores of >2.000. Nevertheless, partial 16S rRNA gene sequencing still represents the gold standard for the identification of this species. Due to the challenging identification of C. tuberculostearicum, we presume that this organism is often misidentified and its clinical relevance is underestimated. The antimicrobial susceptibility profile of C. tuberculostearicum presented here reveals that 14 (87.5%) of the 16 strains analyzed exhibited multidrug resistance.

Epidemiological, bacteriological and molecular studies on caseous lymphadenitis in Sirohi goats of Rajasthan, India.

Corynebacterium pseudotuberculosis is the causative agent of caseous lymphadenitis (CL), a chronic debilitating disease of goats. In the present study, a total of 575 goats of Sirohi breed on an organized farm situated in the semi-arid tropical region of Rajasthan, India were clinically examined. Pus samples from superficial lymph nodes of 27 (4.7%) adult goats presenting clinical lesions suggestive of CL were collected for bacteriological and molecular analyses. Of these goats, 51.9% yielded C. pseudotuberculosis on the basis of morphological, cultural and biochemical characteristics. A polymerase chain reaction (PCR) assay targeting proline iminopeptidase gene specific to C. pseudotuberculosis was developed that confirmed all 14 bacterial isolates. The specificity of the PCR product was confirmed by sequencing of the 551-bp amplicon in both senses, showing 98-100% homology with published sequences. Thus, overall prevalence rate based on clinical, bacterial culture and PCR assay were found to be 4.7%, 2.4% and 2.4%, respectively. The PCR assay developed in this study was found to be specific and rapid, and could be used for confirmation of CL in goats as an alternative method to generally cumbersome, time-consuming and less reliable conventional methods.

Typhlitis and abdominal cystic lymphangiomatosis in a Mt. Carmel blind mole rat (Nannospalax (ehrenbergi) carmeli).

An abdominal cystic lymphangiomatosis in a Mt. Carmel blind mole rat (Nannospalax (ehrenbergi) carmeli) is described. This case was most likely due to a congenital abnormality with long-term compensation by the animal. The case describes the clinical course and subsequent postmortem examination. The death in the animal was caused by an abscess in the peritoneal wall and subsequent peritonitis.

Cystic Neutrophilic Granulomatous Mastitis.

Granulomatous lobular mastitis (GLM) is an infrequent inflammatory breast disease, which can simulate malignancy on the basis of clinical and imaging features. It is typically found in parous or lactating women. The differential diagnosis of granulomatous mastitis includes infections caused by bacterial, fungal or mycobacterial agents, and autoimmune disorders like rheumatoid arthritis, sarcoidosis, giant cell vasculitis, and granulomatosis with polyangiitis. Cystic neutrophilic granulomatous mastitis (CNGM) is a sporadic sub-type of GLM that can be linked with infection with Gram-positive bacilli, specifically, Corynebacterium. It is characterised by lipogranulomas that comprise of "cystic" spaces lined by neutrophils which may contain Gram-positive rod-shaped bacteria. The majority of cases of GLM are still "idiopathic" as this pattern of inflammation still remains a mystery. We herein report three cases of CNGM and review the relevant literature. Key Words: Granulomatous mastitis, Corynebacterium, Gram-positive rods, Inflammatory breast disease, Cystic neutrophilic granulomatous mastitis.

Green concretions on the left axillae.

Case study A man, 47 years of age, with an unremarkable past medical history, attended our dermatology outpatient clinic having developed changes in the colour and texture of the hair of his left axillae 2 weeks earlier, causing him moderate itching. He did not remember any changes in his lifestyle or recall any changes in sweating patterns.

Corynebacterium freneyi Bacterial Septicemia Secondary to Contagious Ecthyma in a Wild Muskox (Ovibos moschatus).

A wild muskox (Ovibos moschatus) with dermatitis typical of contagious ecthyma had secondary bacterial septicemia with Corynebacterium freneyi that included laminitis, hepatitis, and suppurative encephalitis. This case supports the association between orf virus infection and fatal secondary infections, which may have contributed to population declines on Victoria Island, Canada.