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C Brennen

Publications and source records attributed to C Brennen.

17 recordsLinked to original sources
PubMed2001

Pneumonia in long-term care: a prospective case-control study of risk factors and impact on survival.

BACKGROUND: Pneumonia is a major cause of morbidity and mortality in long-term care facilities. Prior studies of pneumonia have failed to identify risk factors potentially amenable to intervention. Our objectives were to (1) identify modifiable risk factors for the occurrence of pneumonia and (2) determine the long-term impact of pneumonia on survival. METHODS: We performed a case-control study among residents of a Veterans Affairs long-term care facility. Case patients included all patients developing pneumonia from 2 days to 1 year after admission. Control subjects were matched for admission date, level of nursing care, and dependence in activities of daily living. Patients were followed up for 2 years or until death or discharge from the facility. RESULTS: We identified 104 case-control pairs. Risk factors significantly associated with pneumonia included witnessed aspiration (odds ratio, 13.9; 95% confidence interval, 1.7-111.0; P =.01), sedative medication (odds ratio, 2.6; 95% confidence interval, 1.2-5.4; P =.01), and comorbidity score (odds ratio, 1.2; 95% confidence interval, 1.0-1.4; P =.05). Mortality due to pneumonia was 23% at 14 days. Patients with pneumonia had a significantly higher mortality than did controls at 1 year (75% vs 40%; P<.001); survival curves converged at 2 years. In a Cox proportional hazards regression model, an episode of pneumonia was independently associated with mortality during follow-up (odds ratio, 2.6; 95% confidence interval, 1.7-3.9; P<.001). CONCLUSIONS: Among long-term care patients closely matched for age, level of dependency, and duration of institutionalization, an episode of pneumonia is associated with significant excess mortality that persists for up to 2 years. Two identified risk factors, large-volume aspiration and receipt of sedating medication, are potentially amenable to intervention.

Activities of Daily Living↗
PubMed2000

Legionnaires' disease in a newly constructed long-term care facility.

OBJECTIVES: To determine whether a newly-constructed long-term care facility would become colonized with Legionella and whether Legionnaires' disease would occur in residents of this new facility. DESIGN: Prospective environmental surveillance of the hospital's water distribution system for the presence of Legionella pneumophila during construction. Utilization of diagnostic tests for Legionnaires' disease in cases of nosocomial pneumonia. SETTING: The Pittsburgh VA Health Care System, Aspinwall Division, a two-building 400-bed complex. PARTICIPANTS: Six patients who acquired Legionnaires' disease while in the facility. INTERVENTION: Installation of copper-silver ionization systems. MEASUREMENTS: Isolation of L. pneumophila from potable water and the occurrence of Legionnaires' disease. RESULTS: L. pneumophila serogroup 1 was recovered from the water distribution system within 1 month of operation; 74% (61/82) of distal sites were positive during construction. In the first 2 years of occupancy, six cases of legionellosis were diagnosed. Both clinical isolates of L. pneumophila were identical to environmental isolates by pulsed field gel electrophoresis (PFGE). Copper-silver ionization systems were installed to control Legionella in the water system. CONCLUSIONS: We conclude that long-term care residents are at risk for acquiring nosocomial Legionnaires' disease in the presence of a colonized water system, even in a newly constructed building.

Aged↗
PubMed1998

Vancomycin-resistant Enterococcus faecium in a long-term care facility.

OBJECTIVE: To describe the epidemiology and natural history of colonization with vancomycin-resistant Enterococcus faecium (VREF) in a long-term care facility. DESIGN: All patients in whom VREF was isolated were followed prospectively, with rectal swab cultures at 2-week intervals, until discharge, death, or clearance of VREF. Clearance was defined as two consecutive negative cultures. In addition, three prevalence surveys were conducted of all patients in residence on one 34-bed intermediate care ward. SETTING: A 400-bed, long-term care Veterans Affairs facility. PARTICIPANTS: Thirty-six patients colonized with VREF. RESULTS: Vancomycin-resistant Enterococcus faecium was identified in 24 of the 36 patients at the time of transfer from an acute care facility. Seventeen patients had concomitant methicillin-resistant Staphylococcus aureus, and seven patients had a recent history of Clostridium difficile-associated diarrhea. VREF in these patients persisted for a median of 67 days after identification. Treatment of VREF colonization with antimicrobials was associated with prolongation of colonization. Serial surveillance of the 34-bed ward found stable rates of colonization, with only three documented instances of VREF acquisition. During 2.5 years of surveillance for infection, a single case of bacteremia occurred in a patient in whom colonization with VREF could not be demonstrated by rectal swab culture. No infections occurred in patients colonized with VREF. CONCLUSIONS: Long-term care patients have protracted carriage of VREF. Most will improve over time; however, receipt of antimicrobial therapy is associated with prolongation of VREF carriage. The risk of VREF infection is low in this population. When there are appropriate contact precautions, patient to patient transmission occurs at a low rate. These observations can be used to design a practical infection control strategy for long-term care facilities.

Adult↗
PubMed1997

Multiply antibiotic-resistant gram-negative bacilli in a long-term-care facility: a case-control study of patient risk factors and prior antibiotic use.

OBJECTIVE: To determine the relation between prior exposure to specific antimicrobials and acquisition of gram-negative bacilli resistant to multiple beta-lactam and aminoglycoside antibiotics among long-term-care patients. DESIGN: Case-control study. Cases were patients from whom multiply resistant Enterobacteriaceae or Pseudomonas aeruginosa were isolated; controls were patients from whom nonresistant bacteria of the same species were isolated. Prospectively defined risk factors included underlying illness, activity level, presence of decubitus ulcers, presence of indwelling devices, and prior exposure to specific antimicrobial agents. Resistant and control isolates of P aeruginosa were compared using pulsed-field gel electrophoresis (PFGE) of genomic DNA after digestion with XbaI. SETTING: 390-bed long-term Veterans' Affairs facility. RESULTS: We identified 35 patients with multiply resistant Enterobacteriaceae and 24 patients with multiply resistant P aeruginosa. Of the resistant Enterobacteriaceae, 87% of isolates were resistant to piperacillin, 55% to ceftazidime, and 90% to gentamicin. Acquisition of multiply resistant Enterobacteriaceae was associated with presence of decubitus ulcers (odds ratio [OR], 12.2; 95% confidence interval [CI95], 3.3-44.2; P = .0002) and prior receipt of ampicillin (OR, 13.7; CI95, 2.2-84; P = .005). Of resistant isolates of P aeruginosa, 88% were resistant to piperacillin, 25% to ceftazidime, 42% to imipenem, and 67% to ciprofloxacin. Isolation of a multiply resistant P aeruginosa was associated with total days of antimicrobial exposure (OR, 1.07; CI95, 1.01-1.12; P = .011) and not with prior receipt of any individual agent. Eleven multiply resistant isolates shared a common PFGE pattern. CONCLUSIONS: In our long-term-care facility, acquisition of multiply resistant Enterobacteriaceae was associated with the presence of decubitus ulcers and prior exposure to ampicillin. Acquisition of resistant P aeruginosa was associated with total antibiotic exposure. Molecular typing of P aeruginosa isolates implicated patient-to-patient transmission of a limited number of resistant strains.

Aged↗
PubMed1996

Pneumonia in a long-term care facility. A prospective study of outcome.

BACKGROUND: Pneumonia is a major cause of morbidity and mortality among patients in long-term care facilities. OBJECTIVES: To conduct a prospective study of 108 consecutive patients who acquired pneumonia in a Veterans Affairs facility from January through December 1993, and to identify (1) the short- and long-term outcome of pneumonia, (2) the determinants of outcome, and (3) the frequency of recurrent episodes. METHODS: Patient characteristics, including scores from the Activities of Daily Living (ADL) Index of Katz et al and the Comorbidity Index of Charlson et al, were recorded End points were survival at 14 days and 12 and 24 months, recurrent episodes of pneumonia, and hospitalization for nonpneumonic illness. RESULTS: Fourteen-day mortality was 19%; outcome was significantly related to the ADL score. There was no relationship between short-term outcome and age or the Comorbidity Index score. Mortalities at 12 and 24 months were 59% and 75%, respectively. Long-term survival also correlated with the ADL score. For the least debilitated patients (ie, those with an ADL score < or = 10), mortalities were 33% and 48% at 12 and 24 months, respectively; for those with ADL scores of 11 to 15, the corresponding mortalities were 60% and 75%; and for those with ADL scores of 16 or greater, the mortalities were 65% and 77% (P = .02). Within 12 months, 43% of the survivors had additional episodes, and 37% required transfer to an acute care facility for other diagnoses. Functional status did not change among the most dependent patients. CONCLUSIONS: Functional status is the major determinant of survival following pneumonia. Pneumonia in a debilitated patient in a long-term care facility predicts recurrent pneumonia and death within 1 to 2 years.

Activities of Daily Living↗
PubMed1993

Infection with methicillin-resistant Staphylococcus aureus among hospital employees.

OBJECTIVE: To describe the spectrum of clinical infection caused by methicillin-resistant Staphylococcus aureus (MRSA) in healthcare workers. DESIGN: Case series. SETTING: Two Veterans Affairs hospitals in which methicillin-resistant S aureus (MRSA) is endemic. PATIENTS: Five employees presenting to employee health or infectious disease clinic. RESULTS: All employees had had direct exposure to patients colonized with MRSA. Employee infections included cellulitis, impetigo, folliculitis, paronychia, and conjunctivitis. MRSA was isolated from all clinically infected sites and from the anterior nares of two employees. Three employees received a variety of ineffective oral antimicrobials before MRSA was recognized as the causative agent. All infections responded to appropriate therapy. CONCLUSIONS: Employees of hospitals with endemic MRSA may acquire MRSA infection. Presentation in our employees was that of relatively uncomplicated soft tissue infection, but several employees received inappropriate therapy before bacteriologic diagnosis. We recommend that culture and susceptibility testing be obtained prior to institution of therapy when hospital employees present with soft tissue infection.

Adult↗
PubMed1993

Choosing appropriate criteria for tuberculin positivity and conversion in a long-term care facility.

OBJECTIVES: The Centers for Disease Control and Prevention has issued new criteria for conversion of the tuberculin skin test; in persons over 35 years of age, an increase in induration of at least 15 mm is considered indicative of new tuberculous infection. We reviewed our experience in a tuberculosis control program in a long-term care facility to assess the applicability of the new criteria to our patient population. DESIGN: Retrospective review of seven years of tuberculosis control records and outbreak investigation. SETTING: Long-term care Veterans Affairs hospital. PATIENTS: All patients in the facility between 1985 and June 1992 who received routine admission and annual tuberculin skin testing or who were evaluated for possible exposure to active tuberculosis. A total of 2,342 skin tests were performed. RESULTS: Mean increase in skin test diameter in patients with at least two prior negative tests and known exposure to active tuberculosis was 13.9 +/- 4.7 mm. Frequency distribution histograms of skin test sizes of initial tuberculin testing in the entire population indicated 10 mm induration as a reasonable criterion for initial positivity. CONCLUSIONS: In our long-term care population, an increase in skin test induration of 10 mm may indicate new tuberculous infection. Criteria for skin test conversion derived from ambulatory populations in other geographic areas may not apply in all situations. Prevalence of infection with Mycobacterium tuberculosis and prevalence of skin test reactivity due to nontuberculous mycobacteria are likely to influence the predictive value of criteria for tuberculin conversion in a given population.

Adult↗
PubMed1992

Bacteremia in a long-term-care facility: a five-year prospective study of 163 consecutive episodes.

The clinical features, microbiological characteristics, and outcomes of 163 episodes of bacteremia occurring at a long-term-care facility were evaluated. The rate of nosocomial bacteremia increased from 0.20 to 0.36 cases/1,000 patient-days from 1985 to 1989; there was a parallel increase in the rate of all nosocomial infections combined. Bacteremia was documented in 6.5% of all hospital-acquired infections. The majority of isolates were gram-negative, and Providencia stuartii was the most common gram-negative species. Staphylococcus aureus was the most frequent isolate; one-third of S. aureus strains were resistant to methicillin. Bacteremia was polymicrobial in 36 episodes (22%), 14 of which involved an enterococcal species. Portals of entry included the urinary tract (55%), the respiratory tract (11%), and soft tissue (9%). Overall mortality was 21.5%. Death was significantly associated with residence on the intermediate-care unit, the presence of a respiratory infection, a change in mental status, and relatively recent admission. Optimal management of bacterial infection in a long-term-care setting requires the availability of blood culture results. Initial decisions about antibiotic therapy should be made in light of the likelihood of infection with multiresistant organisms and of polymicrobial infection.

Adult↗
PubMed1991

Methicillin-resistant staphylococcal colonization and infection in a long-term care facility.

OBJECTIVE: To determine the natural history of colonization by methicillin-resistant Staphylococcus aureus (MRSA) among patients in a long-term care facility. We specifically sought to determine if MRSA colonization was predictive of subsequent infection. DESIGN: Cohort study. SETTING: Long-term Veterans Affairs Medical Center. PATIENTS: A total of 197 patients residing on two units were followed with regular surveillance cultures of the anterior nares. MAIN OUTCOME MEASUREMENT: The development of staphylococcal infection. RESULTS: Thirty-two patients were persistent carriers of MRSA and 44 were persistent carriers of methicillin-susceptible strains (MSSA). Twenty-five percent of MRSA carriers had an episode of staphylococcal infection compared with 4% of MSSA carriers and 4.5% of non-carriers (P less than 0.01; relative risk 3.8; 95% CI, 2.0 to 6.4). The rate of development of infection among MRSA carriers was 15% for every 100 days of carriage. Using logistic regression analysis, persistent MRSA carriage was the most significant predictor of infection (P less than 0.001; odds ratio, 3.7). Seventy-three percent of all MRSA infections occurred among MRSA carriers. Isolates of MRSA from 7 patients were typed. Colonizing and infecting strains had the same phage type in all 7 patients and the same pattern of plasmid EcoRI restriction endonuclease fragments in 5 patients. CONCLUSIONS: Colonization of the anterior nares by MRSA predicts the development of staphylococcal infection in long-term care patients; most infections arise from endogenously carried strains. Colonization by MRSA indicates a significantly greater risk for infection than does colonization by MSSA. The results offer a theoretic rationale for reduction in MRSA infections by interventions aimed at eliminating the carrier state.

Aged↗
PubMed1991

Association with prior fluoroquinolone therapy of widespread ciprofloxacin resistance among gram-negative isolates in a Veterans Affairs medical center.

We performed a case-control study of risk factors for the acquisition of ciprofloxacin-resistant gram-negative isolates in a Veterans Affairs medical center. Sixty-five patients with resistant isolates and 50 control patients were identified. Prior fluoroquinolone use was significantly more frequent among patients with resistant isolates than it was among controls (58 versus 20%; P = 0.0001). The association with prior quinolone use was stronger in the long-term-care division (81 versus 32%; P = 0.0005) than it was in the acute-care division (29 versus 0%; P = 0.015). On multivariate analysis, prior receipt of a fluoroquinolone was the single most significant risk factor for isolation of a ciprofloxacin-resistant gram-negative organism (P = 0.0001).

Anti-Infective Agents↗
PubMed1991

Use of ciprofloxacin versus use of aminoglycosides for therapy of complicated urinary tract infection: prospective, randomized clinical and pharmacokinetic study.

The efficacy of oral ciprofloxacin was compared with that of parenteral aminoglycoside for therapy of complicated urinary tract infection in a prospective randomized trial. The setting was a chronic-care Veterans Administration facility in which long-term bladder catheterization and resistant bacteria were common. Sixty-five consecutive patients were stratified for presence and type of bladder catheter, the presence of Providencia and Pseudomonas aeruginosa organisms versus other urinary pathogens, and renal dysfunction. A pharmacokinetic study of ciprofloxacin concentrations in serum and urine was performed with selected patients. Urinary catheters were present in 94%. All patients were symptomatic, and 58.5% had fever. Ciprofloxacin, 500 mg every 12 h orally, was compared with parenteral aminoglycoside for 7 to 10 days. Clinical response, defined by resolution of symptoms and fever at 5 to 9 days posttherapy (short-term) and 28 to 30 days posttherapy (long-term), was essentially identical for both treatment groups. Bacteriologic response, defined by sterile urine cultures, showed that ciprofloxacin was significantly more efficacious (P = 0.0005) than aminoglycoside at 5 to 9 days posttherapy. However, by 28 to 30 days, the response rate was essentially identical. Emergence of resistance to the study antibiotic was seen in 62 and 70% of those who did not show a bacteriological response and were receiving ciprofloxacin and aminoglycosides, respectively. Concentrations of ciprofloxacin and aminoglycoside in the urine substantially exceeded the MIC for the urinary pathogens isolated, although these concentrations did not correlate with short-term bacteriologic response for either antibiotic. Ciprofloxacin was efficacious in complicated urinary tract infection compared with the current standard of parenteral aminoglycoside among catheterized patients with relatively resistant bacteria.

Administration, Oral↗
PubMed1990

Conjunctivitis associated with methicillin-resistant Staphylococcus aureus in a long-term-care facility.

PURPOSE: To determine the clinical characteristics of conjunctivitis associated with methicillin-resistant Staphylococcus aureus (MRSA) in a long-term-care facility. PATIENTS AND METHODS: We followed 20 episodes of MRSA-associated conjunctivitis in 19 patients occurring over a three-year period in a 432-bed long-term-care facility. RESULTS: The clinical picture was that of a purulent conjunctivitis from which MRSA was isolated on culture. Seventeen patients had severe, pre-existing neurologic impairment. Nine were colonized by MRSA before the onset of conjunctivitis. Seven of eight patients treated with oral ciprofloxacin and all eight patients treated with topical vancomycin showed clinical resolution of conjunctivitis. Persistence of MRSA colonization at a variety of anatomic sites was noted after therapy following 14 episodes. CONCLUSION: MRSA-associated conjunctivitis in our long-term-care facility was notable for its occurrence in patients with severe neurologic disease. Both oral ciprofloxacin and topical vancomycin therapy were associated with clinical resolution. Since MRSA is endemic in many long-term-care facilities, it is likely that MRSA-associated conjunctivitis will be increasingly recognized.

Adult↗
PubMed1988

Occult endemic tuberculosis in a chronic care facility.

During the course of a tuberculosis skin testing program at a chronic care Veterans Administration Medical Center, we uncovered evidence of occult transmission of endemic tuberculosis. Skin test conversion of eight patients (one of whom had unsuspected progressive primary tuberculosis) and two employees was ultimately traced to a patient in whom tuberculosis was first diagnosed at autopsy three years earlier. Identification of employee skin test conversions was a key factor in recognizing and terminating disease transmission. Throughout the institution, 33% of patients were tuberculin-positive; 10.8% demonstrated the booster phenomenon after initial negative skin tests. Prevalence of tuberculin positivity among employees was 28%. Twelve percent of initially tuberculin-negative employees converted during employment. Our experience documents the value of tuberculin testing of both patients and staff in a chronic care environment, and the necessity of vigorous investigation of skin test conversions.

Adult↗
PubMed1984

A prospective study of nosocomial infections in a chronic care facility.

To elucidate the epidemiology of nosocomial infections occurring in nursing homes and chronic care facilities, the authors undertook a prospective study of patients requiring two different levels of nursing care. The overall rate of infection was higher on the intermediate care ward than on the nursing home ward (1.35 versus 0.67 infections/100 patient care days). Pneumonias and symptomatic urinary tract infections accounted for 49 per cent of all infections. Eight of ten cases of pneumonia occurring on the nursing home ward were diagnosed in the winter months, and no case was diagnosed in the summer months. Resistance to gentamicin, tobramycin, ampicillin, and trimethoprim-sulfa was common among organisms causing symptomatic urinary tract infections.

Adult↗
PubMed1976

Locomotion of flagellates with mastigonemes.

Theoretical hydrodynamic analyses of the locomotion of flagellates with mastigonemes are presented and particular comparison is made within experimental data on Ochromonas malhamensis. The first part of the paper analyses locomotion assuming the mastigonemes are rigid and maintain a fixed and normal position relative to the flagellum. The predicted propulsive velocity of 60 mum/sec for Ochromonas agrees well with the observed values of 55-60 mum/sec. It is shown that the propulsive system of Ochromonas represents a compromise between the need for efficient rectilinear propulsion and the need to manoeuvre and accelerate. The effect of rigid mastigonemes which are maintained at non-zero angles to the flagellar normal is also calculated and demonstrates a significant degradation of performance when this angle is greater than about 10 degrees. The latter part of the paper investigates the more complex but more realistic situation in which the mastigonemes flex during the motion according to the instantaneous hydrodynamic forces imposed upon them. The cyclical flexing history of a mastigoneme with passage of a flagellar wave and the consequent velocity of propulsion are obtained for a variety of geometric configurations and structural mastigoneme stiffnesses. It is demonstrated that there exists a relatively small transition range in the values of mastigoneme flexibility below which the mastigonemes are essentially rigid and above which they become totally ineffective hydrodynamically so that the flagellum can be regarded as essentially smooth. Since the transition value of the modulus of elasticity is about 5 dynes/mum2 (or stiffness of 3.5 X 10(-16) dyne cm2) for the mastigonemes of Ochromonas it would appear that the actual value must be in excess of this. Comparison is made with the structural properties of the micro-tubules in eukaryote cilia and flagella and with prokaryote flagella. The latter comparison suggests that the mastigonemes of Ochromonas are just rigid enough to produce the observed propulsive effect.

Animals↗