Although gram-negative meningitis is rare in our hospital, between July, 1982 and July, 1983 clusters of cerebrospinal fluid (CSF) smears were reported positive for gram-negative bacilli. Fourteen specimens were obtained by diagnostic lumbar punctures, and one was obtained during a myelogram. No CSF cultures were positive, and a diagnosis of factitious meningitis was eventually established for each patient. Nonviable gram-negative bacilli were found in 6.7% of manometers, and 23.3% to 90% of the specimen tubes tested from the same lots of commercial lumbar puncture trays. It was estimated that there were between 44 and 333 organisms per specimen tube. Two lots of the commercial myelogram trays yielded nonviable gram-negative bacilli from 50% of the specimen tubes and 33.3% of the manometers tested. Retrospective review of laboratory records for 1982 and 1983 revealed 23 total CSF smears positive for gram-negative bacilli. No CSF grew gram-negative bacilli, and chart reviews confirmed a diagnosis of factitious meningitis in each case. In addition to the clusters of false-positive smears, this had occurred sporadically in both years. The problem did not recur after separate sterile tubes were provided for CSF collection. Physicians and laboratories should be aware that nonviable contaminants in commercial products may be a source of false-positive CSF gram-stained smears.

Nosocomial infection rates were computed for 5,031 patients at an oncology center during a 20-month period. Twelve percent of the patients developed nosocomial infections, accounting for a total of 802 infections. The overall incidence of nosocomial infections during this study period was 6.27 infections per 1,000 patient days. The highest incidence of nosocomial infections was found in patients having acute myelogenous leukemia (30.49 infections per 1,000 patient days); bone and joint cancer (27.27 infections per 1,000 patient days); and liver cancer (26.58 infections per 1,000 patient days). The respiratory tract was the most common site of infection, followed by blood-stream, surgical wound, and urinary tract infections. Staphylococcus aureus, Escherichia coli, Pseudomonas aeruginosa, Klebsiella pneumoniae, and coagulase-negative staphylococci were most frequently implicated as pathogens. The distribution of specific types of infection according to underlying malignancy was also tabulated. These data provide nosocomial infection rates, common pathogens, and sites of infection for cancer patients, thus assisting in directing appropriate therapy for these patients.

Four bone marrow transplant recipients consecutively occupying the same room on our Oncology-Hematology Special Care Unit (OHSCU) became colonized with Chaetomium species between January and April, 1987. These patients, aged 27 to 43 years, were immunocompromised as a result of intensive chemotherapy, and were consequently at increased risk for development of invasive fungal infection. At the time of Chaetomium colonization, all patients were febrile, two had transient new infiltrates on chest x-ray, and three were receiving amphotericin B therapy. Subsequent environmental cultures revealed Chaetomium contamination of the OHSCU air-handling system, including the HEPA (high-efficiency particulate air) filters in seven of the nine rooms comprising the unit. Because fungal colonization of HEPA filters used to create a “protective environment” for immunocompromised patients can occur and can serve as a source for patient infections, guidelines concerning proper surveillance of these HEPA filters should be established. We suggest that before a new patient enters a “protected” room, the clean side of the HEPA filter should be cultured. If fungi are recovered from that culture, we would recommend changing the filter.

We initiated a prospective study of penile prosthesis implant surgery to evaluate risk factors for infection and other complications. Twenty-one patients admitted for surgery or related complications were evaluated over a seven-month period. The two types of penile prostheses implanted were (1) inflatable and (2) semirigid. Nine of 21 patients (43%) developed postoperative complications. Although cephapirin and gentamicin were given prophylactically, four of nine patients had four wound infections and one case of pneumonia. One case of Bacteroides fragilis bacteremia was due to stool incontinency during surgery. In two of the wound infections, removal and reinsertion of the prosthesis was necessary. Other complications included hypotension during surgery, prosthesis malfunction and malposition, and urethral tears. There were no significant associations between infection and age, length of surgery, or type of prosthesis used. These complications contributed to prolonged hospital stay and readmission (87 extra days for the infected patients at a cost of $44,000). Antibiotic costs to treat the infections totaled $1,900. Prospective evaluation by infection control practitioners of various elective surgeries can be useful in quantitating the complication rate and targeting patients at risk, with the goal of minimizing hospital costs.

The CDC category I recommendation for high-level disinfection of pressure-monitoring transducers between uses imposes substantial costs. This practice has not been shown to be useful when disposable transducer domes are used. A prospective, randomized, double-blind study assessed the consequences of wiping transducers with alcohol between uses rather than sterilizing with ethylene oxide. We studied 5,197 transducer courses with disposable domes involving 2,202 patients in intensive care units during 15 months. There was no significant difference between the two treatment regimens in the risk of positive cultures of fluids from monitored lines, of cultures of cannula tips or of a positive blood culture. We conclude that under normal conditions, ie, in the absence of a cluster of transducer-related bacteremias, wiping transducers with alcohol between uses is sufficient when disposable domes are used.

During the period July 1983 through December 1984, aminoglycoside-resistant Acinetobacter calcoaceticus var anitratus (ACA) were isolated from 98 patients in a university hospital. Eighty-seven percent of patients (85/98) acquired aminoglycoside-resistant ACA in the intensive care unit (ICU) and 92% (90198) of all initial isolates were from sputum. ICU patients with respiratory colonization/infection with aminoglycoside-resistant ACA were compared with matched ICU controls with other gram-negative rods in sputum. Compared with controls, the duration of ICU stay prior to colonization/infection with aminoglycoside-resistant ACA was significantly longer for cases (14.7 days υ 5.9 days, P = 0.002). Although exposures to devices and procedures were not significantly different for the two groups, cases received respiratory therapy significantly longer than did controls (14.7 days υ 6.6 days, P = 0.006). Prior to isolation of aminoglycoside-resistant ACA in sputum, cases received more cephalosporins than did controls (1.9 υ 1.2, P = 0.018); aminoglycoside usage in the two groups was comparable but cases tended to have received aminoglycoside for longer durations before colonization/infection than had controls (9.0 days υ 6.1 days, P = 0.08). Following sputum isolation of ACA, 6 of 22 cases developed ACA bacteremia compared with bacteremia in 2 of 22 controls. We conclude that factors predisposing to colonization/infection with aminoglycoside-resistant ACA were extended ICU care, prolonged respiratory therapy, and prior therapy with cephalosporins and aminoglycoside. In addition, ACA may be a more common cause of secondary bacteremia than previously appreciated.

Between March 1984 and February 1986, ten patients admitted to a spinal cord injury/stroke rehabilitation unit became bacteriuric with a strain of Serratia marcescens resistant to ampicillin, cephalothin, cefoxitin, ticarcillin, cotrimoxazole, gentamicin, and tobramycin. All the patients were catheterized, and in most, bacteriuria was asymptomatic. The organism was also recovered from their hospital environment (sinks, toilets, urine-collecting basins). Analysis of total plasmid content of multiresistant isolates revealed the presence of two plasmids (7 kilobase, 25.5 kilobase), not found in aminoglycoside susceptible strains of Serratia marcescens. Restriction endonuclease analysis and Southern hybridization (DNA probe: 25.5 kilobase plasmid) verified that these plasmids were identical. The 25.5 kilobase plasmid was purified, introduced by transformation into an Escherichia coli strain C recipient, and was found to mediate resistance to gentamicin and tobramycin. The emergence of multiresistant Serratia marcescens coincided with an increase in antibiotic usage on the ward. The reservoir seemed to be the urinary tracts of asymptomatic catheterized patients and their contaminated hospital environment.

We studied 157 episodes of infection or colonization with enterococci in 122 patients over a six-month period. One hundred twelve episodes (71.3%) occurred in patients over age 60 years. The most common sites for isolation of enterococci were the urinary tract, and bone and soft tissue. Nosocomial acquisition of enterococci occurred in 74.7% of all infections, and an additional 21% of episodes occurred in patients who had been transferred from another hospital or were regularly seen in the clinic. The overall mortality was 19.6%; 71.4% of those with bacteremia died. Enterococci appear to be significant pathogens, especially in older men in veterans' acute care hospitals and nursing home care units.

I read with great interest the article by Kotilainen and Gantz in Infection Control [now Infection Control and Hospital Epidemiology] regarding biological indicators (BIs) for use with flash sterilization processes. Although this study was conducted with greater care than previous investigations in this area, we believe that certain relevant factors regarding the effect of BI design on BI performance may have been overlooked. Because of differences in the design and construction of the BIs evaluated, a significant variation in response to flash sterilization or high temperature processing may result. Such an effect was first noted by Perkins et al and has been commented on by Reich and Fitzpartrick and Joslyn.

The composition and antibiotic sensitivity pattern of bacteria recovered from the hands of nurses and physicians in two service units of a major teaching hospital were compared with those found in a control population. Significant differences in the composition of bacteria were found in dermatology and oncology unit personnel. Staphylococcus aureus was recovered from 31% of dermatology nurses and 37% of dermatology physicians compared with 20% of oncology nurses, 15% of oncology physicians, and 17% of controls. Oncology personnel had a significantly higher carriage of gramnegative bacteria, yeasts, and multiple antibiotic-resistant, aerobic coryneforms (group JK bacteria). Both dermatology and oncology nursing personnel were colonized by organisms resistant to multiple antibiotics. Methicillin resistance was found in 26% and 66% of the staphylococci recovered from dermatology and oncology nurses respectively. Flora from physicians on the two units had sensitivity patterns similar to controls.

During an eight-month period, 25 hospitalized patients became infected or colonized with methicillin-resistant Staphylococcus aureus (MRSA) in a 464-bed acute care, medical-surgical teaching hospital. There were only five cases during the eight months prior to the outbreak period (P < 0.0001). Initial measures, including category-specific isolation and education, did not limit the spread of the outbreak of a strain of MRSA. This prompted institution of additional measures including (1) strict isolation of all infected and colonized cases; (2) prospective microbiological surveillance to detect additional cases; (3) multiple site cultures of identified cases to determine the extent of colonization; (4) employee and environment surveillance; (5) antibiotic decolonization of patients and employees; and (6) educational efforts. The highest number of personnel carriers were noted in one of the critical care units where most of the cases occurred. The decolonization protocol was 100% effective for personnel carriers. The incidence of nosocomial cases of MRSA fell to zero in the five months following the implementation of the strategy. The cost of the entire eradication process was approximately half that of treating a single MRSA bacteremia.

We performed a prospective randomized study on 71 patients on chronic outpatient hemodialysis to determine whether a sterile technique was better than a clean technique for preparation of the skin over the vascular access site prior to cannulation. In addition, we wanted to determine overall and site-specific infection rates, microbial etiologies of infection, and risk factors for infection. The overall infection rate was 4.7 infections per 100 dialysis months; the vascular access-site infection rate was 1.3 infections per 100 dialysis months; and the rate for bacteremia was 0.7 cases per 100 dialysis months. Staphylococcus aureus was the most common pathogen, but infections were equally divided between gram-positive cocci and gram-negative bacilli. Advanced age (P = 0.02), a low Karnofsky activity score (P = 0.05), poor hygiene (P = 0.0004) and number of hospitalizations (P = 0.0002) were risk factors for infections in general while only poor hygiene (P = 0.002) was a risk factor for vascular access-site infection. Sterile preparation of the skin over the vascular access site was no more effective at preventing infection than was clean technique (P = 0.80). Maintenance of good personal hygiene may be one of the most important measures for prevention of infections in hemodialysis patients