Immunohistochemical Detection of Potential Microbial Antigens in Granulomas in the Diagnosis of Sarcoidosis

Sarcoidosis may have more than a single causative agent, including infectious and non-infectious agents. Among the potential infectious causes of sarcoidosis, Mycobacterium tuberculosis and Propionibacterium acnes are the most likely microorganisms. Potential latent infection by both microorganisms complicates the findings of molecular and immunologic studies. Immune responses to potential infectious agents of sarcoidosis should be considered together with the microorganisms detected in sarcoid granulomas, because immunologic reactivities to infectious agents reflect current and past infection, including latent infection unrelated to the cause of the granuloma formation. Histopathologic data more readily support P. acnes as a cause of sarcoidosis compared with M. tuberculosis, suggesting that normally symbiotic P. acnes leads to granuloma formation in some predisposed individuals with Th1 hypersensitivity against intracellular proliferation of latent P. acnes, which may be triggered by certain host or drug-induced conditions. Detection of bacterial nucleic acids in granulomas does not necessarily indicate co-localization of the bacterial proteins in the granulomas. In the histopathologic diagnosis of sarcoidosis, M. tuberculosis-associated and P. acnes-associated sarcoidosis will possibly be differentiated in some patients by immunohistochemistry with appropriate antibodies that specifically react with mycobacterial and propionibacterial antigens, respectively, for each etiology-based diagnosis and potential antimicrobial intervention against sarcoidosis.

The Efficacy of Lactic Acid Immersion as an Antimicrobial Intervention in Beef Sub-Primal Fabrication

ObjectivesTo perform an in-plant validation of a lactic acid immersion (2–5%) intervention in 6 different subprimals on the fabrication floor.Materials and MethodsSwab samples (n = 324) were taken before and after intervention application from six different processing lines. Each subprimal had a 500 cm2 area swabbed using sterile materials. Each repetition included 18 samples per line, 9 before and 9 after intervention, for a total of 108 samples per repetition. Swab samples were immediately chilled and shipped overnight to the TTU Food Microbiology laboratory for microbial analysis. Samples were stomached at 230 rpm for 30 s and for each subprimal, 3 individual samples were composited into one. Serial dilutions were performed and 1ml of each composite was plated onto Enterobacteriaceae, aerobic plate count, Escherichia coli and coliform Petrifilms in duplicate. Counts were transformed into LogCFU/cm2 and statistical analysis was performed to determine differences between before and after treatment samples with a 0.05 probability threshold.ResultsMicrobial counts of all four microorganisms evaluated were significantly reduced (P < 0.05) after the lactic acid immersion (2–5%) intervention application in subprimals. Total coliform counts before and after treatment were 0.31 and 0.06 LogCFU/cm2, respectively. Enterobacteriaceae counts in the subprimals were in average 0.40 LogCFU/cm2 before interventions and 0.06 LogCFU/cm2 after intervention application. Overall aerobic plate counts were 1.77 LogCFU/cm2 before intervention and 1.14 LogCFU/cm2 after intervention. Generic E. coli counts after intervention were lower than the detection limit (< 1 CFU/20 cm2).ConclusionBased on data collected, it is reasonable to conclude that the lactic acid immersion intervention is effective in reducing common microbial indicators on subprimals inside the fabrication floor, improving the safety of the product.

Considerations in the Diagnosis and Management of Lower-Extremity Infections in Injection Heroin Users: A Case Series

Background: On a national level, heroin-related hospital admissions have reached an all-time high. With the foot being the fourth most common injection site, heroin-related lower-extremity infections have become more prevalent owing to many factors, including drug preparation, injection practices, and unknown additives. Methods: We present a 16-month case series in which eight patients with lower-extremity infections secondary to heroin abuse presented to The Jewish Hospital in Cincinnati, Ohio. Results: Three cases of osteomyelitis were seen. All of the infections were cultured and yielded a wide array of microbes, including Staphyloccoccus, Streptococcus, Bacillus, Serratia, Prevotella, and Eikenella. All of the patients were treated with intravenous antibiotic agents, with nearly all receiving combination therapy. Seven of the eight patients underwent surgery during their hospital stay, with two undergoing amputation. Only half of the patients followed up after discharge. Conclusions: This case series brings to light many considerations in the diagnosis and management of the heroin user, including multivariable attenuation of immunity, existing predisposition to infection backed by unsterile drug preparation and injection practices, innocuous presentation of deep infections, microbial spectrum, and recommendations on antimicrobial intervention, noncompliance, and poor follow-up. By having greater knowledge in unique considerations of diagnosis and treatment, more efficient care can be provided to this unique patient population.

Evaluation of Commercial Prototype Bacteriophage Intervention Designed for Reducing O157 and Non-O157 Shiga-Toxigenic Escherichia coli (STEC) on Beef Cattle Hide

Microbiological safety of beef products can be protected by application of antimicrobial interventions throughout the beef chain. This study evaluated a commercial prototype antimicrobial intervention comprised of lytic bacteriophages formulated to reduce O157 and non-O157 Shiga-toxigenic Escherichia coli (STEC) on beef cattle hide pieces, simulating commercial pre-harvest hide decontamination. STEC reduction in vitro by individual and cocktailed phages was determined by efficiency of plating (EOP). Following STEC inoculation onto hide pieces, the phage intervention was applied and hide pieces were analyzed to quantify reductions in STEC counts. Phage intervention treatment resulted in 0.4 to 0.7 log10 CFU/cm2 (p < 0.01) E. coli O157, O121, and O103 reduction. Conversely, E. coli O111 and O45 did not show any significant reduction after application of bacteriophage intervention (p > 0.05). Multiplicity of infection (MOI) evaluation indicated E. coli O157 and O121 isolates required the fewest numbers of phages per host cell to produce host lysis. STEC-attacking phages may be applied to assist in preventing STEC transmission to beef products.