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V L Yu

Publications and source records attributed to V L Yu.

At least 181 records · Page 10Linked to original sources
PubMed1988

Legionnaires' disease in the work environment: implications for environmental health.

Legionnaires' disease is a severe pneumonia caused by the bacterium Legionella pneumophila. Outbreaks of Legionnaire's disease have occurred in hotels, hospitals, and homes but had not been reported yet in the work environment. The authors report the occurrence of Legionnaires' disease in three employees of two industrial plants. The potable water in the two plants contained high numbers of Legionella pneumophila. Monoclonal antibody subtyping of environmental and patient isolates of L. pneumophila implicated one of the plants as the source for the disease. L. pneumophila was eradicated from this plant using acidic and caustic scale removers, calcium hypochlorite, and a biocide. A systematic approach to Legionnaires' disease in the work environment, a problem which can be expected to be recognized with increasing frequency, is presented.

Antibodies, Monoclonal↗
PubMed1988

Surgical complications related to insertion of penile prostheses with emphasis on infection and cost.

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) semi-rigid. 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.

Cephapirin↗
PubMed1988

Comparison of molecular methods for subtyping patients and epidemiologically linked environmental isolates of Legionella pneumophila.

We used the molecular techniques of monoclonal antibody typing, plasmid analysis, and outer membrane protein profiling to subtype 159 patients' and environmental (water distribution system) isolates of Legionella pneumophila serogroup 1 from 18 institutions. The ability of these techniques to match patients' and epidemiologically linked environmental isolates from outbreaks of Legionnaires' disease at seven institutions was also compared. Two different panels of monoclonal antibodies (I and II) identified nine subtypes (one new disease-causing subtype) and six subtypes, respectively. The Bellingham 1 subtype type was the most common among environmental isolates, and the Philadelphia 1 subtype predominated among patients' isolates from all institutions except the Veterans Administration Medical Center in Pittsburgh, Pennsylvania. The source of an isolate (patient vs. environment) and its monoclonal antibody subtype were significantly associated (P less than .01). With use of the molecular techniques tested, the subtypes of patients' isolates were identical to those of epidemiologically linked environmental isolates from the same hospital.

Antibodies, Monoclonal↗
PubMed1988

Antibiotic use during major head and neck surgery.

The appropriate use of prophylactic antimicrobial therapy in patients undergoing major contaminated surgery is an important issue for the head and neck surgeon. A series of five sequential, prospective, randomized, double-blind clinical trials of antibiotics for patients undergoing major contaminated oncologic head and neck surgery are reviewed and summarized. The information generated from the study of these 547 patients indicates that a number of drugs or drug combinations have similar efficacy when employed in adequate dosage. The bacteriologic spectrum of the prophylactic drug should include oral microflora, especially anaerobic bacteria. The administration of antibiotics effective against gram-negative aerobic bacteria may be unnecessary. Perioperative antibiotic administration should be initiated prior to surgery. To date, no evidence exists to support prolonged administration of antibiotics beyond the first 24 hours following surgery.

Anti-Bacterial Agents↗
PubMed1988

Simultaneous infection with Cryptococcus neoformans and Legionella pneumophila. In vivo expression of common defects in cell-mediated immunity.

We describe 3 patients with simultaneous infection by Cryptococcus neoformans and Legionella pneumophila. Legionnaires' disease (pneumonia) occurred shortly after onset of cryptococcal meningitis in a cardiac transplant patient receiving ciclosporin, a second patient with chronic lymphocytic leukemia and a third patient with Hodgkin's disease and autoimmune hemolytic anemia. Defects in cell-mediated immunity have been identified in patients with hematologic malignancies and in those who have received organ transplants. Clinical and experimental data suggest that the primary host defense mechanism against cryptococcal and Legionella infection involves cell-mediated immunity. Thus, the simultaneous occurrence of cryptococcal and L. pneumophila infection in these 3 patients supports experimental studies which have demonstrated common host defense mechanisms against both pathogens.

Adult↗
PubMed1988

Clindamycin pharmacokinetics and tissue penetration after head and neck surgery.

Penetration of clindamycin into surgical wounds was studied in 10 patients undergoing radical head and neck surgery. Patients received one preoperative and three postoperative intravenous doses of clindamycin 600 mg. During surgery, samples of plasma and sternocleidomastoid muscle were obtained. Additional plasma samples were collected just before the fourth dose of clindamycin, just after that dose was infused, and 1, 2, 4, 6, 8, and 12 hours after dosing. Samples of wound exudate were collected at 2, 4, 6, 8, and 12 hours after the fourth dose. The muscle, plasma, and wound exudate samples were assayed for clindamycin base by a gas-liquid chromatographic method. Plasma and wound exudate samples obtained during surgery and one and eight hours after the fourth dose were assayed by a radial immunodiffusion technique for content of alpha 1-acid glycoprotein (AAG), the major binding protein for clindamycin. Pharmacokinetic values for plasma and wound drainage were calculated and compared. Concentrations of clindamycin in muscle (three to six hours after the first dose) ranged from 0.6 to 5.1 micrograms/g; the ratio of tissue to plasma concentrations ranged from 0.24 to 0.82. The highest mean clindamycin concentration in wound drainage was 4.9 micrograms/mL after the fourth dose, approximately 90% of simultaneous plasma concentrations. Concentrations in wound exudate exceeded those measured in plasma four hours after the dose, and elimination from the wound was slower than from plasma. AAG concentrations in plasma increased from a mean of 89 mg/dL intraoperatively to 134 mg/dL postoperatively. AAG was present in wound exudate in concentrations that were approximately 53% of those observed in plasma.(ABSTRACT TRUNCATED AT 250 WORDS)

Aged↗
PubMed1987

Legionnaires' disease acquired within the homes of two patients. Link to the home water supply.

Two patients with sporadic community-acquired legionnaires' disease are described. Legionella pneumophila was isolated from sputum specimens, and seroconversion of antibody titers was demonstrated for both patients. Legionella pneumophila was also recovered from the residential water supply of both patients. In each case, the serogroup of the environmental organism matched that of the infecting organism. In one patient, serogroup 3 was isolated--a rare cause of legionnaires' disease, and in the second case, monoclonal antibody testing confirmed that the serogroup 1 organisms isolated from sputum and residential water supply samples were identical. The incubation period of legionnaires' disease is presumed to be up to two weeks. Because of medical problems, both patients had been confined to their homes for the entire two weeks before the onset of symptoms. This is the first report that links acquisition of community-acquired legionnaires' disease to contaminated water supplies within the homes of susceptible patients.

Aged↗
PubMed1987

Cryptococcal tonsillitis in a patient with chronic lymphocytic leukemia: an unusual manifestation of cryptococcal disease.

We present a case of chronic tonsillitis in a patient with chronic lymphocytic leukemia. Despite empiric radiation and antibiotic therapy, the patient's sore throat and tonsillar enlargement persisted. Excisional biopsy of the involved tonsil revealed the presence of Cryptococcus neoformans. Blood cultures also yielded cryptococcus. Specific antifungal therapy resulted in cure. To our knowledge, this is the first case report of cryptococcal infection of the tonsil. This case illustrates the pitfalls of empiric therapy in an immunosuppressed host.

Aged↗
PubMed1987

Susceptibility of 100 blood isolates of Pseudomonas aeruginosa to 19 antipseudomonal antibiotics: old and new.

The in vitro susceptibility of 19 antipseudomonal antibiotics, old and new, were tested against 100 blood isolates of Pseudomonas aeruginosa. The isolates were taken from consecutive bacteremic patients hospitalized in nine Pittsburgh hospitals from 1983 to 1984. Twelve percent of isolates tested were tobramycin-resistant. All of the tobramycin-resistant isolates were sensitive to apalcillin, azlocillin, aztreonam, cefsulodin, ceftazidime, ciprofloxicin, and imipenem. Two isolates were resistant in vitro to all beta-lactam antibiotics tested, but sensitive to all aminoglycosides. One hundred percent of isolates tested were susceptible to imipenem, whereas, 98% were susceptible to apalcillin and cefsulodin. The lowest MIC90 was 2 mg/L for ciprofloxicin. Tolerance of P. aeruginosa (MIC90/MBC90 ratio greater than 32) was not observed for any antimicrobial agent.

Anti-Bacterial Agents↗
PubMed1987

Legionnaires' disease: an emerging surgical problem.

Legionnaires' disease is an important, although often overlooked, complication in the patient postoperatively. Up to 50% of all nosocomial legionellosis in the hospitals reviewed was found in surgical patients. Patients undergoing a transplant procedure are at highest risk, but occurrence is common in the surgical patient undergoing general anesthesia, endotracheal intubation, or both. Aerosolization, aspiration, and direct instillation of contaminated water during manipulation of the respiratory tract are likely mechanisms of transmission. The usual clinical presentation is that of a nonspecific pneumonia. Specialized laboratory techniques including selective culture media, direct fluorescent antibody stains, and serological detection of antibodies are necessary for accurate diagnosis. If these tests are not routinely available, Legionnaires' disease may remain undiagnosed. Environmental surveillance of the hospital water distribution system is advisable for hospitals with a large surgical case load. If transplantation is performed, such surveillance is mandatory.

Cross Infection↗
PubMed1987

Determinants of Legionella pneumophila contamination of water distribution systems: 15-hospital prospective study.

We conducted a prospective environmental study for Legionella pneumophila in 15 hospitals in Pennsylvania. Hot water tanks, cold water sites, faucets, and showerheads were surveyed four times over a one-year period. Sixty percent (9/15) of hospitals surveyed were contaminated with L pneumophila. Although contamination could not be linked to a specific municipal water supplier, most of the contaminated supplies came from rivers. Parameters found to be significantly associated with contamination included elevated hot water temperature, vertical configuration of the hot water tank, older tanks, and elevated calcium and magnesium concentrations of the water (P less than 0.05). This study suggests that L pneumophila contamination could be predicted based on design of the distribution system, as well as physicochemical characteristics of the water.

Cross Infection↗
PubMed1987

Routine culturing for Legionella in the hospital environment may be a good idea: a three-hospital prospective study.

The source for nosocomial Legionnaires' disease is the water distribution system. However, the implications for legionella contamination in a hospital without known Legionnaires' disease is unclear. Therefore, culturing for Legionella pneumophila in the environment has not been routinely recommended. The authors conducted a prospective pneumonia study in three hospitals, none of which was known to have a major problem with endemic legionellosis. The water system of Hospital 1 was colonized with L. pneumophila, serogroup 1; Hospital 2 was colonized by L. pneumophila, serogroup 5 (which is rarely associated with disease); Hospital 3 was essentially free of L. pneumophila. Sputum culture on selective legionella media, direct fluorescent antibody testing, and serology were performed for all nosocomial pneumonias regardless of clinical impression. At the end of the study the incidence of nosocomial legionnaires' disease was found to be 9%, 0%, and 0% in Hospitals 1, 2, and found to be 9%, 0%, and 0% in Hospitals 1, 2, and 3, respectively. In Hospital 1, monoclonal antibody subtyping confirmed that the patient isolates were identical to the environmental isolates. The authors conclude that environmental culturing, despite the absence of known Legionnaires' disease, is useful. Positive cultures from the hospital water supply would mandate the introduction of legionella testing into the laboratory and stimulate physicians to consider Legionnaires' disease when encountering nosocomial pneumonias.

Cross Infection↗
PubMed1987

Comparative assessment of chlorine, heat, ozone, and UV light for killing Legionella pneumophila within a model plumbing system.

Nosocomial Legionnaires disease can be acquired by exposure to the organism from the hospital water distribution system. As a result, many hospitals have instituted eradication procedures, including hypercholorination and thermal eradication. We compared the efficacy of ozonation, UV light, hyperchlorination, and heat eradication using a model plumbing system constructed of copper piping, brass spigots, Plexiglas reservoir, electric hot water tank, and a pump. Legionella pneumophila was added to the system at 10(7) CFU/ml. Each method was tested under three conditions; (i) nonturbid water at 25 degrees C, (ii) turbid water at 25 degrees C, and (iii) nonturbid water at 43 degrees C. UV light and heat killed L. pneumophila most rapidly and required minimal maintenance. Both UV light and heat (60 degrees C) produced a 5 log kill in less than 1 h. In contrast, both chlorine and ozone required 5 h of exposure to produce a 5 log decrease. Neither turbidity nor the higher temperature of 43 degrees C impaired the efficacy of any of the disinfectant methods. Surprisingly, higher temperature enhanced the disinfecting efficacy of chlorine. However, higher temperature accelerated the decomposition of the chlorine residual such that an additional 120% volume of chlorine was required. All four methods proved efficacious in eradicating L. pneumophila from a model plumbing system.

Chlorine↗