Antimicrobial monitoring and evaluation.

Effective antimicrobial use is an essential component of patient care. Drug use evaluation should include the prophylactic, therapeutic, and empiric use of antimicrobials. The infection control practitioner has the unique knowledge and skills in epidemiology to be effective in the monitoring and evaluation process. This review outlines a variety of techniques to monitor and evaluate trends in the use of antimicrobial agents in health care facilities. Methods related to antimicrobial monitoring and evaluation are summarized.

Proteeae species bacteriuria accompanying Proteeae species groin skin carriage in geriatric outpatients.

There have been numerous reports of Proteeae species urinary tract infections among elderly individuals. To explore a possible urinary carrier source of Proteeae species in this population, the frequency of aerobic gram-negative bacillus (AGNB) bacteriuria at the greater than or equal to 10(2)/ml level was determined in 67 ambulatory elderly outpatients classified as to Proteeae group (Morganella, Proteus, Providencia) groin carriage by a set of two skin cultures obtained at least 1 week apart. None had urethral catheters, symptomatic infections, skin ulcers, or recent antibiotic therapy. We found AGNB bacteriuria in 12 of 15 carriers (80%) and in 21 of 52 noncarriers (40%) (P = 0.009). Proteeae species bacteriuria occurred in eight carriers (53.3%) and six noncarriers (11.5%) (P = 0.001). At the 10(2) to 10(4)/ml level, Proteeae species were isolated in urine specimens from seven carriers (46.7%) and four noncarriers (7.7%) (P = 0.001). There was concordance of species of skin and urine Proteeae isolates in six carriers. By contrast, non-Proteeae AGNB bacteriuria at any level was present in four Proteeae species carriers (26%) and 15 noncarriers (28.8%) (P greater than 0.05). There was a 36.7% frequency of Proteeae species bacteriuria in nursing home residents, in contrast to 8.1% among those living in private homes; this parallels the greater frequency of Proteeae species groin carriage among nursing home residents in the study population. Low-level urinary colonization with Proteeae species accompanying Proteeae species groin skin colonization in elderly individuals is a hitherto unrecognized finding. This may account for the greater frequency of Proteeae species urinary infections in this population.

Indications for alcohol or bland soap in removal of aerobic gram-negative skin bacteria: assessment by a novel method.

A patient contact model was devised for health care workers (HCWs) to define heavy hand contamination with aerobic gram-negative bacilli (AGNB) that requires alcohol for complete removal. In patients, AGNB quantitation was per ml cup scrub fluid; in HCWs per ml glove juice. Following 15-second contact, two Proteeae groin carriers yielding greater than or equal to 4 log10 AGNB (high burden) transmitted greater than or equal to 3 log10 in 67% of 24 tests of six HCWs, and less than or equal to 2 log10 in 29%. Two carriers yielding less than or equal to 3 log10 in 38%. At less than or equal to 2 log10 HCW acquisitions, soap eliminated all AGNB in three of 10; alcohol in eight of eight (p = 0.009). Contact with densely colonized patient skin may cause heavy AGNB contamination of HCWs' hands that generally necessitates alcohol for complete removal.

Proteeae groin skin carriage in ambulatory geriatric outpatients.

Aerobic gram-negative bacillus (AGNB) groin skin carriage was prospectively studied in ambulatory geriatric outpatients: 42 from three nursing homes and 44 from private homes. Initially, 12 (28.6%) Proteeae carriers were in the former group and 3 (6.8%) were in the latter (P = 0.01). At one year, 6 of 7 surviving nursing home carriers remained Proteeae carriers while none from private homes remained carriers (P = 0.007). The annual prevalence of Proteeae carriage was 14 (33.3%) in nursing homes and 4 (9.1%) in private homes (P = 0.008); of non-Proteeae AGNB carriage, the annuyal prevalence was 2 (4.8%) and 4 (11.4%), respectively. Nursing home subjects had similar initial health characteristics; however, by one year, 5 of 12 carriers in contrast to 3 of 30 noncarriers were dead of chronic disease (P = 0.03). These nursing homes included persons with chronic diseases that apparently facilitated Proteeae carriage. Urethral catheters, skin ulcers, and recent antibiotics were not factors.

Sporadic bacteremia complicating central venous catheter use in a community hospital: a model to predict frequency and aid in decision-making for initiation of investigation.

Sporadic bacteremia complicating single-lumen central venous catheter (CVC) use was prospectively recorded in a community hospital in 1981 and 1982. Sixty-four of 1258 (5.1%) patients had definite bacteremia. A nested case-control study was then undertaken to identify predictive risk factors. Fifteen statistically significant factors found in the 1981 cohort were tested in the 1982 cohort, and four remained significant for both years. Univariate and multiple logistic regression analysis on both years' findings, separately and together, identified two independently associated factors: diagnosed respiratory colonization/infection (p less than 0.0001) and serum albumin level (p less than 0.001). Based on these factors, an equation was developed to express the probability of bacteremia. Solving this equation provides an infection control practitioner with an expected rate of bacteremia that complicates CVC use and provides an aid for decision-making for investigation in the absence of clusters.

Proteeae groin skin carriage among nursing home residents--resistance to antiseptics.

Proteeae carriage was evaluated in groin skin carriers following vigorous antiseptic application. Three Proteus mirabilis carriers were treated with 60% isopropyl alcohol or 4% chlorhexidine, observed to prevent skin contact, and then recultured; at four and eight hours P mirabilis numbers remained undiminished. Ten Proteeae carriers received a series of nine body baths with soap, chlorhexidine, and 0.75% povidone-iodine plus three cefazolin injections over 16 to 34 days; cumulative treatments failed to clear seven carriers. Within three months, all were again carriers. Proteeae carriers also had affinity for groin carriage of various aerobic gram-negative bacilli (AGNB) including cefazolin-resistant strains. In seven subjects, more than one AGNB species were recovered shortly after applying an antiseptic. Proteeae groin skin carriage appears to reflect a major change in the nature of resident bacteria on intact groin skin.