Biomedical subjects
Publications and source records attributed to M M McNeil.
A case of Broviac catheter-related bacteremia in a 3-year-old boy infected with Oerskovia turbata is discussed. The blood cultures of the patient remained positive despite antibiotic therapy, and only with catheter removal was his blood sterilized. The microbiology and antimicrobial susceptibilities of this organism are described.
Between 23 and 27 July 1987, three infants at one hospital developed severe bronchopneumonia associated with respiratory failure, thrombocytopenia, and leukocytosis. Two infants died; at postmortem examination, Malassezia furfur was identified in their lung tissues. M. furfur was isolated from cultures of blood, urine, and stool samples from the infant who survived. All documented M. furfur infections occurred in infants with a birth weight of less than 1,000 g; the attack rate was 42.9% (three of seven infants). A case-control study comparing the three cases and nine infants randomly selected from infants in the neonatal intensive care unit during the outbreak showed the following variables to be significantly associated with case-infants: younger gestational age (less than 26 weeks), hyaline membrane disease, duration of ventilation, duration of antimicrobial therapy, and the presence of a Broviac catheter. In a second case-control study, in which case-infants were compared with birth weight-matched controls, only the duration of antimicrobial therapy was significantly associated with case-infants. A point prevalence culture survey showed that 2 of 10 infants and 2 of 11 personnel were colonized with M. furfur. This cluster suggests that M. furfur can be transmitted from an infected or colonized infant to other infants. Infection control practices should be aimed at (i) identifying high-risk infants and (ii) reemphasizing the importance of hand washing.
From September 1981 through April 1984, 20 patients at one hospital were identified with Ewingella americana pseudobacteremia. Case-control studies demonstrated an association between having a positive blood culture for E. americana and having blood for culture obtained simultaneously with blood obtained for coagulation studies (15 of 19 case patients versus 4 of 38 controls; P = 4.5 X 10(-7)). Review of blood-drawing procedures showed that blood for coagulation studies and culture was drawn with the same syringe, and coagulation tubes were filled before blood culture tubes. Some phlebotomists were not using new sterile needles to inoculate blood culture bottles. Collection tubes for coagulation studies were prepared in the hospital, and E. americana was isolated from all 52 unused coagulation tubes tested. Solutions prepared in the hospital may constitute a persistent inanimate environmental reservoir for this uncommon microorganism. Pseudobacteremia can result in unnecessary antimicrobial therapy for some patients, incurring the risks of adverse drug reactions, selection of drug-resistant bacteria, and increased health care costs.
During an outbreak of pseudobacteremia in a children's hospital, Ewingella americana was found in blood cultures from 20 patients. E. americana was inoculated into blood culture bottles at the time of specimen collection due to cross contamination from nonsterile, citrated blood collection tubes used for coagulation studies. Antimicrobial susceptibility testing and plasmid profiling were used to assess the association between patient isolates and isolates from unused blood collection tubes. All E. americana isolates had similar antibiograms (i.e., resistance only to cephalothin) when tested at 37 degrees C. However, when the same isolates were tested for antimicrobial susceptibility at 25 degrees C, a different antibiogram (i.e., resistance to chloramphenicol, ampicillin, and cephalothin) was found. The majority of these isolates also demonstrated a unique four-plasmid profile (130, 56, 4.6, and 3.1 megadaltons), and two of these plasmids (130 and 56 megadaltons) were characterized as temperature-sensitive plasmids. An epidemiologic link between outbreak-associated isolates obtained from different time periods in the outbreak was supported by evidence of a significant trend in the ability of the outbreak-associated isolates to reduce nitrate, together with the presence of the resistance antibiogram at 25 degrees C and the demonstration of the unique four-plasmid profile.
Laboratory investigations were conducted to study the growth dynamics of Pseudomonas pickettii in commercial 0.9% sodium chloride solution under various environmental conditions and to determine the retention of these organisms after challenge through a 0.2-micron cartridge filter system. Low numbers of P. pickettii (1 to 10 CFU/ml of test solution) inoculated into commercial vials containing 5 ml of 0.9% sodium chloride solution and 500-ml volumes of 0.9% sodium chloride solution were shown to proliferate over a 168-h incubation period. These organisms demonstrated growth over a wide range of temperatures (15 to 42 degrees C) in this salt solution, and survival studies at 50, 55, and 60 degrees C indicated that this strain was not unusually resistant to heat (with the times required at a given temperature to reduce the surviving microbial population 10-fold [D-values] being 26.0, 1.9, and 0.7 min, respectively). A challenge test demonstrated that P. pickettii organisms were not completely retained by a 0.2-micron cartridge filter. The number of organisms detected increased from 1 CFU/liter of effluent at 1 to 2 min to a maximum of 176 CFU/liter at 4 to 5 min. Our results indicate that P. pickettii can penetrate a 0.2-micron filtration system and that the passage of organisms and subsequent microbial growth in the filter effluent probably are the mechanisms by which these organisms were recovered from "sterile" commercial 0.9% sodium chloride solution.
Several studies have identified nonsterile blood collection tubes as the reservoir for contaminating microorganisms in outbreaks of pseudobacteremia. Microorganisms are thought to be transferred from the nonsterile tubes to the blood culture tubes when blood is drawn for cultures, but the validity of this hypothesis has not previously been tested. We recently investigated an outbreak of Ewingella americana pseudobacteremia in which an epidemiological association was found between pseudobacteremia and the practice of drawing blood for culturing at the same time that blood for coagulation studies is drawn. The nonsterile coagulation tubes, prepared in the hospital, were contaminated with E. americana. We studied three different procedures that personnel reported using to inoculate blood culture tubes after dispensing blood into the coagulation tubes. Although the failure to change or remove the needle before inoculating the blood culture tubes resulted in the highest percentage of cross-contamination, we found that all the techniques we simulated carried some risk of cross-contamination when coagulation tubes were filled first.
Pseudomonas pickettii caused respiratory tract colonization in five infants in the special care nursery of a Chicago hospital. All organisms had the same antimicrobial susceptibilities. Endotracheal suctioning with saline from 5-ml unit-dose vials was identified by epidemiologic investigation as a risk factor for colonization. The vials of saline were contaminated with a strain of P. pickettii having the same antimicrobial susceptibility pattern as the isolates from patients. As part of an investigation of the manufacturing plant where the saline solution was produced, P. pickettii was recovered from deionized water used to make the product and from several sites in the processing line. Bypassing of a 180 degrees F (ca. 82 degrees C) water-holding tank appeared to be temporally related to product contamination. The ability of P. pickettii to survive and grow in this solution has been demonstrated in the laboratory. This outbreak demonstrates that, despite pertinent Food and Drug Administration regulations and company programs for identifying such contamination, intrinsically contaminated solutions can occasionally reach the bedside of the patient.
Germ cell tumors, particularly those of extragonadal origin, have a rare and only recently recognized association with Klinefelter's syndrome. A case of a primary mediastinal embryonal cell carcinoma in a 16-year-old male with Klinefelter's syndrome is reported.
The development of hypertrophic osteoarthropathy in patients with leukaemia or lymphoma presents important diagnostic and therapeutic implications. Patients with these disorders are also predisposed to the development of invasive phycomycosis and aspergillus infections. We report a case of primary bone marrow lymphoma complicated by hypertrophic osteoarthropathy. At postmortem examination there was evidence of disseminated phycomycosis and aspergillus infections. We believe this relationship has not previously been reported.
In 1991, 1208 cases of coccidioidomycosis were reported to the California Department of Health Services, compared with an annual average of 450 during 1986-90. We conducted a study in Tulare County to define the epidemiology of the disease and identify risk factors for severe disease, focusing on the epidemic period September 1991-December 1991. To identify cases, we used data from the Coccidioidomycosis Serology Laboratory at the University of California, Davis, other laboratories, and the Tulare County Health Department's coccidioidomycosis reporting system. We compared patients who were hospitalized with those who were not to determine risk factors for severe disease. We identified 128 cases of acute coccidioidomycosis diagnosed between 1 September and 31 December 1991 (attack rate 41/100,000); south central Tulare County had the highest attack rate. Thirty-five (27%) case-patients were hospitalized. Male sex (relative risk (RR) 2.5, 95% confidence interval (CI) 1.2-5.0), black people and Asian races (RR 4.8, 95% CI 2.4-9.6), and age > or = 20 years (RR 8.3, 95% CI 1.2-57.4) were univariately significant and remained independently associated with hospitalization in multivariate analysis. The 1991 Tulare County outbreak of coccidioidomycosis was part of a much larger outbreak that began in California during 1991 and continued through 1993. The outbreak was preceded by an unusually rainy spring. Although dust reduction measures during times of increased coccidioidomycosis incidence can help reduce exposure, definitive control awaits the development of a safe, effective vaccine.
To compare the species distribution and antimicrobial susceptibility of aerobic actinomycetes, we evaluated 366 isolates referred to the Centers for Disease Control from October 1985 through February 1988. We used conventional biochemical tests to identify the various species. Four species accounted for 191 (52%) of aerobic actinomycete isolates: Nocardia asteroides (98 isolates), Actinomadura madurae (42 isolates), Streptomyces griseus (28 isolates), and Nocardia brasiliensis (23 isolates). Sputum and wounds were the most common sources. No isolate was resistant to amikacin, no N. brasiliensis isolate was resistant to sulfamethoxazole or trimethoprim-sulfamethoxazole, and no A. madurae isolate was resistant to ceftriaxone or imipenem. In summary, our findings show that unusual species of aerobic actinomycetes can cause infection, colonization, or both and that antimicrobial resistance varies markedly by species.
An unlicensed injectable medicine sold as adrenal cortex extract (ACE*) and distributed in the alternative medicine community led to the largest outbreak of Mycobacterium abscessus infections reported in the United States. Records from the implicated distributor from January 1, 1995, to August 18, 1996, were used to identify purchasers; purchasers and public health alerts were used to identify patients. Purchasers and patients were interviewed, and available medical records were reviewed. Vials of ACE* were tested for mycobacterial contamination, and the product was recalled by the U.S. Food and Drug Administration. ACE* had been distributed to 148 purchasers in 30 states; 87 persons with postinjection abscesses attributable to the product were identified. Patient and vial cultures contained M. abscessus identical by enzymatic and molecular typing methods. Unusual infectious agents and alternative health practices should be considered in the diagnosis of infections that do not respond to routine treatment.
Anaerobiospirillum succiniciproducens is a motile, spiral anaerobic bacterium with bipolar tufts of flagella. Reports of clinical illness due to A. succiniciproducens are rare. In a retrospective review of anaerobic isolates referred to the Centers for Disease Control (CDC) from January 1, 1975, through January 31, 1986, isolates of A. succiniciproducens from the blood of 21 patients were identified. A single patient whose blood isolate had not been received at CDC was included in the review. These 22 patients were from 15 states. Their mean age was 58.6 years. Underlying disorders included alcoholism, atherosclerosis, malignancy, surgery, diabetes mellitus, and dental caries. Clinical features included gastrointestinal tract signs and symptoms in 17 (77%) of 22, fever greater than 38 degrees C in seven (37%) of 19, and leukocytosis of more than 10,000 cells/mm3 in 11 (58%) of 19. Although 16 patients received antimicrobial therapy, its effect on outcome was unclear. A. succiniciproducens was reported to have contributed to the deaths of seven patients. Disorders predisposing patients to anaerobic infections may put them at increased risk for A. succiniciproducens bacteremia. The presence of antecedent gastrointestinal tract signs and symptoms suggests that the gastrointestinal tract might be the primary portal of entry.
THE EMERGENCE OF newly identified fungal pathogens and the reemergence of previously uncommon fungal diseases is primarily related to increases in the numbers of susceptible persons: people with HIV infection, bone marrow and organ transplant recipients, cancer patients being treated with chemotherapy, critically ill persons, and very low birth weight ( < or = 1500 g) infants. These immunocompromised populations are at risk for infection not only with opportunistic pathogens (for example, Pneumocystis, Candida, Cryptococcus, Trichosporon, Malassezia, Aspergillus, Penicillium marneffei, and numerous other moulds or yeasts) but also with fungal pathogens that usually infect otherwise healthy persons not previously exposed to endemic fungi (for example, Coccidioides immitis, Histoplasma capsulatum, and Blastomyces dermatitidis) and Sporothrix schenckii. Morbidity, mortality, and health care costs associated with fungal infections are high. Addressing the emergence of fungal diseases will require increased surveillance coupled with the availability of rapid, noninvasive diagnostic tests; monitoring the development of resistance to antifungal agents; and research focused on the understanding, prevention, and control of fungal infections.