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Background Bacterial contamination and associated septic transfusion reactions (STRs) remain the leading infectious risk to the blood supply. We sought to characterize the risk and clinical presentation of blood culture-positive transfusion reactions (BCPTRs) and STRs at our institution. Study design and methods A retrospective analysis was conducted of all suspected transfusion reactions reported to the transfusion service at a 1000-bed tertiary academic medical center from January 2009 to September 2016. Routine investigation included review of the clinical presentation, Gram stain, and bacterial culture of residual blood from the transfused product or associated blood bag. BCPTRs were defined by the presence of a positive bacterial culture in the blood product and/or recipient. STRs met definitive Centers for Disease Control and Prevention hemovigilance criteria for transfusion-transmitted infection, with definite imputability and concordant bacterial culture of the blood product and recipient. Results A total of 688,514 blood products were transfused during the study period, 3170 transfusion reactions were reported, and 18 (0.57%) were BCPTRs of which seven (0.22%) were STRs. Fifteen of 18 (83.3%) BCPTRs and six of seven (85.7%) were associated with transfusion of apheresis platelets. Major symptoms and signs of BCPTRs included chills (67%), fever (61%), and nausea and vomiting (50%). Four of seven (57.1%) STRs were classified as severe or life-threatening. Conclusion BCPTRs are rare yet potentially serious. The signs and symptoms of BCPTRs, and associated STRs, are not specific, posing risk of misclassification. Challenges surrounding reporting and case ascertainment underscore the need for laboratory measures to address residual risk of contamination.

Background Working conditions in poultry slaughter/processing plants may expose workers to zoonotic pathogens. We explored exposure to pathogens among poultry slaughter/processing plant workers including job duties as risk factors. Methods We collected questionnaire data on job duties and nasal swabs from 110 workers at one plant in South Carolina. Swabs were tested for Staphylococcus aureus and gram-negative organisms. Isolates were screened for antimicrobial susceptibility. Results There was no differences in prevalence of S. aureus carriage based on job duties. As compared with office or packing workers, the adjusted odds of GNO carriage was 6.29 times (95% CI: 1.43, 27.71) higher in slaughter or carcass processing workers and 5.94 times (95% CI: 0.94, 37.50) higher in cleaning or maintenance workers. Conclusions Poultry processing plant workers may have increased exposure to GNOs, depending on job duties. Am. J. Ind. Med. © 2016 Wiley Periodicals, Inc.

This chapter focuses on nonamplified nucleic acid probes and their current uses in the clinical laboratory. DNA probes are pieces of nucleic acid that are labeled in some way and are designed to seek out and bind to stretches of DNA or RNA that have sequences that are complementary to the probe. In hybridization reactions, a double-stranded DNA molecule is denatured to single strands. Several formats for the hybridization reactions exist: solid phase; in solution (liquid phase); in situ; or by use of a Southern hybridization procedure after gel electrophoresis. In sandwich hybridization assays, one probe is attached to a solid support such as a nitrocellulose filter in single-stranded form and ‘‘captures’’ homologous nucleic acids in liquid samples; a second probe, which recognizes a contiguous area of the nucleic acid, carries the reporter molecule such as a radioisotope or biotin. The target and probe nucleic acids are free to move in solution, maximizing chances that complementary sequences will bind. Southern hybridization involves using purified DNA that is cleaved with restriction endonucleases. There are numerous methods for detecting the binding of probe to target nucleic acid. Commercially available DNA probes used for culture confirmation of bacteria, mycobacteria, and fungi are discussed in the chapter. Of the assays discussed in the chapter, probes for the detection of mycobacteria have had the greatest clinical impact. The chapter describes the utility of nonamplified probes for the diagnosis of sexually transmitted diseases, vaginal infections, and streptococcal pharyngitis.

Zygomycetes are ubiquitous in nature and can cause fulminant infections in the immunocompromised host. Known risk factors include hematologic malignancy, neutropenia, diabetes mellitus, steroid use, and trauma (1). A recent increase in the incidence of zygomycosis compared with candidiasis or aspergillosis may be explained by increasing use of antifungal agents lacking activity against Zygomycetes, in addition to the increasing numbers of higher risk bone marrow transplants (2). Organisms in the genus Rhizopus cause the majority of human infections. They typically manifest as cutaneous, rhino-cerebral, pulmonary, or gastrointestinal infection and may progress to disseminated disease. Cutaneous disease may arise either from direct inoculation of the skin, or less commonly, from hematogenous dissemination. Genital infection is exceedingly uncommon and only 4 cases involving the penis have been reported in the medical literature (3–6). Our case illustrates the diagnostic challenge of penile infection caused by Rhizopus. One of the key diagnostic dilemmas is that the appearance of skin lesions secondary to Rhizopus may be confused with viral eruptions, cutaneous leukemia, and bacterial necrotizing infection. The anatomy, physiology, and lymphatic drainage of the penis and perineum may predispose to rapid dissemination into the deep tissues of the pelvis with nearly universally fatal results. Current management strategies including novel adjuvant therapies are discussed.