Farrin A. Manian

Ehrlichia ewingii, a Newly Recognized Agent of Human Ehrlichiosis

BACKGROUND Human ehrlichiosis is a recently recognized tick-borne infection. Four species infect humans: Ehrlichia chaffeensis, E. sennetsu, E. canis, and the agent of human granulocytic ehrlichiosis. METHODS We tested peripheral-blood leukocytes from 413 patients with possible ehrlichiosis by broad-range and species-specific polymerase-chain-reaction (PCR) assays for ehrlichia. The species present were identified by species-specific PCR assays and nucleotide sequencing of the gene encoding ehrlichia 16S ribosomal RNA. Western blot analysis was used to study serologic responses. RESULTS In four patients, ehrlichia DNA was detected in leukocytes by a broad-range PCR assay, but not by assays specific for E. chaffeensis or the agent of human granulocytic ehrlichiosis. The nucleotide sequences of these PCR products matched that of E. ewingii, an agent previously reported as a cause of granulocytic ehrlichiosis in dogs. These four patients, all from Missouri, presented between May and August 1996, 1997, or 1998 with fever, headache, and thrombocytopenia, with or without leukopenia. All had been exposed to ticks, and three were receiving immunosuppressive therapy. Serum samples obtained from three of these patients during convalescence contained antibodies that reacted with E. chaffeensis and E. canis antigens in a pattern different from that of humans with E. chaffeensis infection but similar to that of a dog experimentally infected with E. ewingii. Morulae were identified in neutrophils from two patients. All four patients were successfully treated with doxycycline. CONCLUSIONS These findings provide evidence of E. ewingii infection in humans. The associated disease may be clinically indistinguishable from infection caused by E. chaffeensis or the agent of human granulocytic ehrlichiosis.

Asymptomatic Nasal Carriage of Mupirocin-Resistant, Methicillin-Resistant Staphylococcus aureus (MRSA) in a Pet Dog Associated with MRSA Infection in Household Contacts

Recurrent methicillin-resistant Staphylococcus aureus (MRSA) infection in a patient with diabetes and in his wife is described. Culture of nares samples from the family dog grew mupirocin-resistant (minimum inhibitory concentration >1024 microg/mL) MRSA that had a pulsed-field gel electrophoresis chromosomal pattern identical to the MRSA isolated from the patients nares and his wifes wound. Further recurrence of MRSA infection and nasal colonization in the couple was prevented only after successful eradication of MRSA from the family dogs nares.

Surgical Site Infections Associated with Methicillin-Resistant Staphylococcus aureus: Do Postoperative Factors Play a Role?

Patients with surgical site infections (SSIs) who underwent surgery during the period of September 1997 through December 1999 and January through July 2001 were retrospectively studied to compare patients infected with methicillin-resistant Staphylococcus aureus (MRSA) with those infected with organisms other than MRSA. Of patients with SSI who had known culture results, 77 (28.5%) of 270 had cultures that yielded MRSA. On univariate analysis, age of >or=70 years, duration of surgery of >or=4 h, duration of postoperative antibiotic treatment of >1 day, and discharge to a long-term care facility (LTCF) were significantly associated with MRSA SSI (P<.05 for all). On multivariate analysis, only discharge to an LTCF (odds ratio [OR], 2.3; P=.04) and duration of postoperative antibiotic treatment of >1 day (OR, 2.0; P=.03) were significantly associated with MRSA SSI; there was also a trend toward MRSA SSI being associated with use of a surgical drain for >1 day (P=.078). Postoperative factors may play a more important role in the causation of MRSA SSI than has previously been appreciated.

Comprehensive Surveillance of Surgical Wound Infections in Outpatient and Inpatient Surgery

A surgeon-specific computer-generated monthly questionnaire was used to improve surveillance of surgical wound infections in outpatients as well as inpatients following discharge. From July 1988 through June 1989, 20,536 surgical procedures were performed at our medical center, of which 53% were for outpatients. The total wound infection rate was 0.63%: 0.13% in outpatients and 1.2% in inpatients (p less than .005). Of the infected wounds, 20% were reported by the survey alone and would have gone undetected by conventional surveillance methods (71.4% of outpatient and 13.8% of inpatient wound infections). As a whole, clean and clean-contaminated wounds in outpatients were much less likely to become infected than those in inpatients. Wound cultures were not obtained in 85% of infections reported by the survey alone, and were less likely to be obtained in outpatients. The average time spent by the infection control department on the survey was approximately two hours per week.

Requirements for infrastructure and essential activities of infection control and epidemiology in out-of-hospital settings: A Consensus Panel report

In 1997 the Association for Professionals in Infection Control and Epidemiology and the Society for Healthcare Epidemiology of America established a consensus panel to develop recommendations for optimal infrastructure and essential activities of infection control and epidemiology programs in out-of-hospital settings. The following report represents the Consensus Panels best assessment of requirements for a healthy and effective out-of-hospital-based infection control and epidemiology program. The recommendations fall into 5 categories: managing critical data and information; developing and recommending policies and procedures; intervening directly to prevent infections; educating and training of health care workers, patients, and nonmedical caregivers; and resources. The Consensus Panel used an evidence-based approach and categorized recommendations according to modifications of the scheme developed by the Clinical Affairs Committee of the Infectious Diseases Society of America and the Centers for Disease Control and Preventions Healthcare Infection Control Practices Advisory Committee.

Isolation of Acinetobacter baumannii Complex and Methicillin-Resistant Staphylococcus aureus from Hospital Rooms Following Terminal Cleaning and Disinfection: Can We Do Better?

OBJECTIVE To study the frequency of isolation of Acinetobacter baumannii complex (ABC) and methicillin-resistant Staphylococcus aureus (MRSA) from surfaces of rooms newly vacated by patients with multidrug-resistant (MDR) ABC following various rounds of routine terminal cleaning and disinfection (C/D) with bleach or 1 round of C/D followed by hydrogen peroxide vapor (HPV) treatment. SETTING A 900-bed tertiary care hospital. METHODS ABC and MRSA cultures were obtained from hospital rooms including 312 rooms (mean, 18.3 sites/room) following 4 rounds of C/D, 37 rooms (mean, 20 sites/room) following 1 round of C/D before and after HPV treatment, and 134 rooms (mean, 20 sites/room) following 1 round of C/D and HPV treatment. RESULTS Following 4 rounds of C/D, 83 (26.6%) rooms had 1 or more culture-positive sites; 102 (1.8%) sites in 51 (16.4%) rooms grew ABC, and 108 (1.9%) sites in 44 (14.1%) rooms grew MRSA. The addition of HPV treatment to 1 round of C/D resulted in a significant drop in ABC- and MRSA-positive room sites (odds ratio, 0 [95% confidence interval, 0-0.8]; P = .04 for both organisms). Following 1 round of C/D and HPV treatment, 6 (4.5%) rooms were culture-positive for ABC, MRSA, or both. CONCLUSIONS Routine terminal C/D of hospital rooms vacated by MDRABC-positive patients may be associated with a significant number of ABC- or MRSA-positive room surfaces even when up to 4 rounds of C/D are performed. The addition of HPV treatment to 1 round of C/D appears effective in reducing the number of persistently contaminated room sites in this setting.

Compliance With Routine Use of Gowns by Healthcare Workers (HCWs) and Non-HCW Visitors on Entry Into the Rooms of Patients Under Contact Precautions

BACKGROUND Modified contact precautions (MCP), defined as routine donning of isolation gowns (along with routine gloving) on entry into the rooms of patients under contact precautions, regardless of the likelihood of direct exposure to the patient or their immediate environment, were instituted at our medical center to reduce nosocomial transmission of common hospital pathogens. OBJECTIVES To study compliance with MCP policy regarding routine gowning in intensive care units (ICUs) and general wards and to determine the relationship between gown and glove use in the care of patients under MCP in ICUs. DESIGN Prospective observational study from February 20, 2004, through January 8, 2005, involving 2,110 persons (1,504 healthcare workers [HCWs] and 606 non-HCW visitors). SETTING A 900-bed tertiary care teaching community hospital. RESULTS Overall compliance with routine gown use was observed for 1,542 persons (73%), including 1,150 HCWs (76%) and 392 visitors (65%) (odds ratio [OR], 1.8 [95% confidence interval {CI}, 1.4-2.2]; P<.001). Visitors in the ICUs (186 [91%] of 204) were more likely than visitors in the general wards (202 [51%] of 398) to comply with gown use (OR, 10 [95% CI, 6.0-17.0]; P<.001). In logistic regression analysis, independent predictors of gown compliance among HCWs were female sex (OR, 2.3 [95% CI, 1.8-3.0]; P<.001) and ICU setting (OR, 2.2 [95% CI, 1.7-2.9]; P<.001). In the ICUs, gown use was highly predictive of glove use among HCWs (positive predictive value, 95%). CONCLUSION Improvement in compliance with gown use at our medical center will require more-intensive educational efforts targeted at male HCWs and at HCWs and visitors on general wards. In the care of ICU patients under MCP, HCW compliance with gown use may be used as a proxy for their compliance with glove use.

Routine screening for methicillin-resistant Staphylococcus aureus among patients newly admitted to an acute rehabilitation unit.

BACKGROUND Following an outbreak of methicillin-resistant Staphylococcus aureus (MRSA) infection in our acute rehabilitation unit in 1987, all patients except in-house transfers (because of their low prevalence of MRSA colonization) underwent MRSA screening cultures on admission. OBJECTIVES To better characterize the current profile of patients with positive MRSA screening cultures at the time of admission to our acute rehabilitation unit, and to determine the relative yield of nares, perianal, and wound screening cultures in this population. METHODS Prospective chart review with ongoing active surveillance for infections associated with the acute rehabilitation unit RESULTS The rate of MRSA isolation from one or more body sites increased significantly from 5% (1987-1988) to 12% (1999-2000) (P = .0009) for newly admitted patients and from 0% to 7% (P < .0001) for in-house transfers. A negative nares culture was highly predictive (98%) of a negative perianal culture. Prior history of MRSA infection or colonization and transfer from outside sources were independently associated with positive MRSA screening cultures. CONCLUSION The rate of MRSA isolation from screening cultures of newly admitted patients, including in-house transfers, has increased significantly during the past decade in our acute rehabilitation unit. When paired with nares cultures, perianal cultures were of limited value in this patient population.

Clostridium difficile Contamination of Blood Pressure Cuffs: A Call for a Closer Look at Gloving Practices in the Era of Universal Precautions

We report an outbreak of Clostridium difficile-associated diarrhea at our medical center following adoption of Universal Precautions. Environmental cultures revealed unexpected contamination of blood pressure cuffs at a rate similar to that for bedside commodes (10% and 11.5%, respectively). An observational survey revealed that healthcare workers in the patient care areas not infrequently failed to remove their potentially stool-contaminated gloves prior to touching clean surfaces, which might have contributed to contamination of blood pressure cuffs.

Whither Continuity of Care

As I walk down the halls of the hospital to see my patients, I cannot help but notice a marked change. The sight of a primary care internist taking care of his or her patients while they are hospit...