Left knee prosthesis-related Mycobacterium goodii infection

Non-tuberculous mycobacteria are increasingly being recognized as important human pathogens. We present the case of a 44-year-old non-diabetic male who underwent left total knee arthroplasty for degenerative arthritis after trauma. He developed left knee swelling and progressively worsening pain over the next 4 weeks. He was referred for treatment using whirlpool baths and developed a blister at the surgical incision site. Repeated aspirations of the left knee failed to show any growth of organism on routine cultures. He finally underwent explantation of the left knee prosthesis with antimicrobial spacer placement 4 months later. Cultures of three different intra-operative specimens turned positive for Mycobacterium goodii. This infection was successfully treated with combination oral antimicrobials for 6 months. The patient underwent revision left knee arthroplasty subsequently and was symptom-free until his last follow-up visit 1 year later. This patient highlights the importance of testing for mycobacteria in prosthesis-related infections with previously negative routine bacterial cultures

Association of hemochromatosis with infectious diseases: expanding spectrum

SummaryWithholding iron from potential pathogens is a host defense strategy. There is evidence that iron overload per se compromises the ability of phagocytes to kill microorganisms. Several hypotheses exist to explain the association of hemochromatosis with infection. A combination of mechanisms likely contributes to the increase in susceptibility to infection in these patients. A review of the current literature delineating various pathogens to which patients with hemochromatosis are potentially susceptible, and recent advances in the understanding of the association of hemochromatosis with infection, are discussed

Measurements of Airborne Influenza Virus in Aerosol Particles from Human Coughs

Influenza is thought to be communicated from person to person by multiple pathways. However, the relative importance of different routes of influenza transmission is unclear. To better understand the potential for the airborne spread of influenza, we measured the amount and size of aerosol particles containing influenza virus that were produced by coughing. Subjects were recruited from patients presenting at a student health clinic with influenza-like symptoms. Nasopharyngeal swabs were collected from the volunteers and they were asked to cough three times into a spirometer. After each cough, the cough-generated aerosol was collected using a NIOSH two-stage bioaerosol cyclone sampler or an SKC BioSampler. The amount of influenza viral RNA contained in the samplers was analyzed using quantitative real-time reverse-transcription PCR (qPCR) targeting the matrix gene M1. For half of the subjects, viral plaque assays were performed on the nasopharyngeal swabs and cough aerosol samples to determine if viable virus was present. Fifty-eight subjects were tested, of whom 47 were positive for influenza virus by qPCR. Influenza viral RNA was detected in coughs from 38 of these subjects (81%). Thirty-five percent of the influenza RNA was contained in particles \u3e4 µm in aerodynamic diameter, while 23% was in particles 1 to 4 µm and 42% in particles \u3c1 µm. Viable influenza virus was detected in the cough aerosols from 2 of 21 subjects with influenza. These results show that coughing by influenza patients emits aerosol particles containing influenza virus and that much of the viral RNA is contained within particles in the respirable size range. The results support the idea that the airborne route may be a pathway for influenza transmission, especially in the immediate vicinity of an influenza patient. Further research is needed on the viability of airborne influenza viruses and the risk of transmission

Hand Hygiene Practices in Adult Versus Pediatric Intensive Care Units at a University Hospital Before and After Intervention

Observations of hand hygiene practices of the health care workers (HCWs) were carried out at a tertiary care center by a single observer in all adult and pediatric intensive care units (ICUs) before and after educational programs. Access to alcohol-based hand rub was also increased. A survey of HCWs was carried out to determine knowledge of hand hygiene. Before interventions, mean adherence to hand hygiene in all ICUs was 54% with significant difference between adult and pediatric ICUs (p \u3c .0001) (35% vs 90%, respectively). Traditional handwashing versus alcohol-based hand rub use was 72% versus 28%, respectively. Following the interventions, there was a significant increase (p \u3c .0001) in hand hygiene adherence in adult ICUs (81%). 46% of survey respondents believed that alcohol-based hand rub could not be used for methicillin resistant Staphylococcus aureus infection and 21% believed that alcohol-based hand rub could be used if hands were soiled. Overall, adherence to hand hygiene in adult ICUs improved with institution of an educational program and increase in accessibility of alcohol-based hand rub. There was a statistically significant increase in the frequency of alcohol-based hand rub use; however, traditional handwashing was still preferred. The survey of HCWs revealed gaps in knowledge regarding methods of hand hygiene

Measurements of airborne influenza virus in aerosol particles from human coughs.

Influenza is thought to be communicated from person to person by multiple pathways. However, the relative importance of different routes of influenza transmission is unclear. To better understand the potential for the airborne spread of influenza, we measured the amount and size of aerosol particles containing influenza virus that were produced by coughing. Subjects were recruited from patients presenting at a student health clinic with influenza-like symptoms. Nasopharyngeal swabs were collected from the volunteers and they were asked to cough three times into a spirometer. After each cough, the cough-generated aerosol was collected using a NIOSH two-stage bioaerosol cyclone sampler or an SKC BioSampler. The amount of influenza viral RNA contained in the samplers was analyzed using quantitative real-time reverse-transcription PCR (qPCR) targeting the matrix gene M1. For half of the subjects, viral plaque assays were performed on the nasopharyngeal swabs and cough aerosol samples to determine if viable virus was present. Fifty-eight subjects were tested, of whom 47 were positive for influenza virus by qPCR. Influenza viral RNA was detected in coughs from 38 of these subjects (81%). Thirty-five percent of the influenza RNA was contained in particles>4 µm in aerodynamic diameter, while 23% was in particles 1 to 4 µm and 42% in particles<1 µm. Viable influenza virus was detected in the cough aerosols from 2 of 21 subjects with influenza. These results show that coughing by influenza patients emits aerosol particles containing influenza virus and that much of the viral RNA is contained within particles in the respirable size range. The results support the idea that the airborne route may be a pathway for influenza transmission, especially in the immediate vicinity of an influenza patient. Further research is needed on the viability of airborne influenza viruses and the risk of transmission