Staphylococcus aureus colonization of healthy military service members in the United States and Afghanistan.

BACKGROUND: Staphylococcus aureus [methicillin-resistant and methicillin-susceptible (MRSA/MSSA)] is a leading cause of infections in military personnel, but there are limited data regarding baseline colonization of individuals while deployed. We conducted a pilot study to screen non-deployed and deployed healthy military service members for MRSA/MSSA colonization at various anatomic sites and assessed isolates for molecular differences. METHODS: Colonization point-prevalence of 101 military personnel in the US and 100 in Afghanistan was determined by swabbing 7 anatomic sites. US-based individuals had received no antibiotics within 30 days, and Afghanistan-deployed personnel were taking doxycycline for malaria prophylaxis. Isolates underwent identification and testing for antimicrobial resistance, virulence factors, and pulsed-field type (PFT). RESULTS: 4 individuals in the US (4 isolates- 3 oropharynx, 1 perirectal) and 4 in Afghanistan (6 isolates- 2 oropharynx, 2 nare, 1 hand, 1 foot) were colonized with MRSA. Among US-based personnel, 3 had USA300 (1 PVL+) and 1 USA700. Among Afghanistan-based personnel, 1 had USA300 (PVL+), 1 USA800 and 2 USA1000. MSSA was present in 40 (71 isolates-25 oropharynx, 15 nare) of the US-based and 32 (65 isolates- 16 oropharynx, 24 nare) of the Afghanistan-based individuals. 56 (79%) US and 41(63%) Afghanistan-based individuals had MSSA isolates recovered from extra-nare sites. The most common MSSA PFTs were USA200 (9 isolates) in the US and USA800 (7 isolates) in Afghanistan. MRSA/MSSA isolates were susceptible to doxycycline in all but 3 personnel (1 US, 2 Afghanistan; all were MSSA isolates that carried tetM). CONCLUSION: MRSA and MSSA colonization of military personnel was not associated with deployment status or doxycycline exposure. Higher S. aureus oropharynx colonization rates were observed and may warrant changes in decolonization practices.

Multidrug-resistant gram-negative bacteria colonization of healthy US military personnel in the US and Afghanistan.

BACKGROUND: The US military has seen steady increases in multidrug-resistant (MDR) gram-negative bacteria (GNB) infections in casualties from Iraq and Afghanistan. This study evaluates the prevalence of MDR GNB colonization in US military personnel. METHODS: GNB colonization surveillance of healthy, asymptomatic military personnel (101 in the US and 100 in Afghanistan) was performed by swabbing 7 anatomical sites. US-based personnel had received no antibiotics within 30 days of specimen collection, and Afghanistan-based personnel were receiving doxycycline for malaria chemoprophylaxis at time of specimen collection. Isolates underwent genotypic and phenotypic characterization. RESULTS: The only colonizing MDR GNB recovered in both populations was Escherichia coli (p=0.01), which was seen in 2% of US-based personnel (all perirectal) and 11% of Afghanistan-based personnel (10 perirectal, 1 foot+groin). Individuals with higher off-base exposures in Afghanistan did not show a difference in overall GNB colonization or MDR E. coli colonization, compared with those with limited off-base exposures. CONCLUSION: Healthy US- and Afghanistan-based military personnel have community onset-MDR E. coli colonization, with Afghanistan-based personnel showing a 5.5-fold higher prevalence. The association of doxycycline prophylaxis or other exposures with antimicrobial resistance and increased rates of MDR E. coli colonization needs further evaluation.

Detection of methicillin-resistant and methicillin-susceptible Staphylococcus aureus colonization of healthy military personnel by traditional culture, PCR, and mass spectrometry.

BACKGROUND: Methicillin-resistant (MRSA) and methicillin-susceptible (MSSA) Staphylococcus aureus colonization is associated with increased rates of infection. Rapid and reliable detection methods are needed to identify colonization of nares and extra-nare sites, particularly given recent reports of oropharynx-only colonization. Detection methods for MRSA/MSSA colonization include culture, PCR, and novel methods such as PCR/electrospray ionization time-of-flight mass spectrometry (ESI-TOF-MS). METHODS: We evaluated 101 healthy military members for S. aureus colonization in the nares, oropharynx, axilla, and groin, using CHROMagar S. aureus medium and Xpert SA Nasal Complete PCR for MRSA/MSSA detection. The same subjects were screened in the nares, oropharynx, and groin using PCR/ESI-TOF-MS. RESULTS: By culture, 3 subjects were MRSA-colonized (all oropharynx) and 34 subjects were MSSA-colonized (all 4 sites). PCR detected oropharyngeal MRSA in 2 subjects, which correlated with culture findings. By PCR, 47 subjects were MSSA-colonized (all 4 sites); however, 43 axillary samples were invalid, 39 of which were associated with deodorant/anti-perspirant use (93%, p < 0.01). By PCR/ESI-TOF-MS, 4 subjects were MRSA-colonized, 2 in the nares and 2 in the oropharynx; however, neither of these correlated with positive MRSA cultures. Twenty-eight subjects had MSSA by PCR/ESI-TOF-MS, and 41 were found to have possible MRSA (S. aureus with mecA and coagulase-negative Staphylococcus (CoNS)). CONCLUSION: The overall 3% MRSA colonization rate is consistent with historical reports, but the oropharynx-only colonization supports more recent findings. In addition, the use of deodorant/anti-perspirant invalidated axillary PCR samples, limiting its utility. Defining MRSA positivity by PCR/ESI-TOF-MS is complicated by co-colonization of S. aureus with CoNS, which can also carry mecA.

Leading a New Team: Critical Lessons Learned.

Leading medical teams as a new attending physician can be a challenging task. This case highlights the important role of leaders in fostering a positive learning environment, developing interpersonal relationships, and establishing clear expectations with regular feedback to improve team function to deliver effective health care.

Invasive Apophysomyces variabilis infection in a burn patient.

Apophysomyces variabilis is an emerging fungal pathogen that can cause significant infections in immunocompetent patients. We report a case of A. variabilis invasive wound infection in a 21-year-old male after a self-inflicted burn injury.

Pythium aphanidermatum infection following combat trauma.

Pythium aphanidermatum is a fungus-like plant pathogen which has never been reported as a cause of human infection. We report a case of P. aphanidermatum invasive wound infection in a 21-year-old male injured during combat operations in Afghanistan.

Community-associated methicillin-resistant Staphylococcus aureus mediastinitis.

Community-associated methicillin (meticillin)-resistant Staphylococcus aureus (CA-MRSA) continues to emerge as a cause of serious infections, chiefly of the skin and soft tissues. We present the first documented case of CA-MRSA mediastinitis in an adult. Blood and mediastinal isolates were characterized as CA-MRSA by pulsed-field gel electrophoresis and susceptibility testing.

Use of a high-flow oxygen delivery system in a critically ill patient with dementia.

We used a high-flow nasal cannula with a patient who required a high fraction of inspired oxygen but could not tolerate a nasal or facial mask. We saw a 92-year-old woman with delirium and dementia in the intensive care unit for multi-lobar pneumonia with severe hypoxemia. Attempts to oxygenate the patient failed because she was unable to tolerate various facial and nasal masks. We then tried a high-flow nasal cannula (Vapotherm 2000i), which she tolerated well, and she had marked improvement in gas exchange and quality of life. The patient had severe health-care-associated pneumonia, accompanied by delirium and hypoxemia. It became apparent that the patient's death was imminent, and the goal of therapy was palliative. She had previously clearly expressed a desire not to undergo intubation and mechanical ventilation. In a situation where the patient was agitated and unable to tolerate a mask, the high-flow cannula reduced her agitation and improved her dyspnea, oxygenation, tolerance of oxygen therapy, and comfort at the end of life. Oxygen via high-flow cannula may enhance quality of life by reducing hypoxemia in patients who are unable to tolerate a mask but need a high oxygen concentration.

Central nervous system infections in patients with severe burns.

BACKGROUND: Central nervous system (CNS) infections develop in 3-9% of neurosurgical ICU patients and 0.4-2% of all patients hospitalized with head trauma. CNS infection incidence in burn patients is unknown and this study sets out to identify the incidence and risk factors associated with CNS infections. METHODS: A retrospective electronic chart review was performed from 1 July 2003 to 30 June 2008 evaluating inpatient medical records along with cerebrospinal fluid (CSF) microbiological results for the presence of CNS infection. The presence of facial and head injuries and burns, along with intracranial interventions were reviewed for association with CNS infections. RESULTS: There were 1964 admissions with 2 patients (0.1%) found to have CNS infection; 1 each with MRSA and Acinetobacter baumannii. Both patients had facial burns and trauma to their head that required intracranial surgery. Of note, both patients had bacteremia with the same microorganisms isolated from their CSF and both survived. Of all patients, 29% had head or neck trauma and burns; 0.35% of those had a CNS infection. Scalp harvest for grafts or debridement of burned scalp was performed on 125 patients of which 9 had an invasive surgical procedure that involved penetration of the skull. The 2 infected patients were from these 9 intracranial surgical patients revealing a 22% infection rate. CONCLUSION: The incidence of CNS infections in patients with severe burns is extremely low at 0.1%. This rate was low even with head and face burns with trauma unless the patient underwent an intracranial procedure.