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M A Neill

Publications and source records attributed to M A Neill.

At least 19 recordsLinked to original sources
PubMed2001

Escherichia coli O157:H7.

E. coli O157:H7 can cause potentially lethal illness in hosts of all ages. These patients often are evaluated and treated by gastroenterologists. The treating physician should administer adequate hydration, usually parenterally, and avoid the use of antibiotics and antimotility agents. The physician needs to notify immediately the appropriate public health authorities of the diagnosis and to ensure that the isolate is recovered by the microbiologist and forwarded for molecular linkage analyses.

Aged↗
PubMed1996

Cryptosporidiosis: an unrecognized cause of diarrhea in elderly hospitalized patients.

Human infection with Cryptosporidium species has been increasingly noted in the past decade. We conducted a broad-based longitudinal review in a community setting and found that a Cryptosporidium species was detected in one-third of the specimens screened over a 5-year period. Thirty-six patients were identified, comprising three distinct clinical groups: persons with human immunodeficiency virus (HIV) infection (18 patients); young, otherwise healthy persons (5 patients); and, surprisingly, chronically ill elderly persons (13 patients). In six (46%) of the 13 elderly patients, both Cryptosporidium and Clostridium difficile toxin was identified, suggesting that Cryptosporidium may be a copathogen in some instances of nosocomial diarrhea. Acquisition in an institutional setting was suspected for nine (69%) of the elderly and three (17%) of the HIV-infected patients. Elderly patients with chronic illnesses constitute a newly recognized category of persons at risk for cryptosporidial infection. In this group cryptosporidiosis may be far more common than previously recognized, may be acquired institutionally, and can mimic and occur with Clostridium difficile-associated diarrhea.

Adolescent↗
PubMed1994

Characteristics of antibiotic-resistant Escherichia coli O157:H7 in Washington State, 1984-1991.

The resistance of Escherichia coli O157:H7 to amoxicillin/clavulanic acid, ampicillin, ceftazidime, ceftriaxone, cefuroxime, cephalothin, chloramphenicol, ciprofloxacin, gentamicin, streptomycin, sulfisoxazole, tetracycline, ticarcillin, tobramycin, and trimethoprim-sulfamethoxazole was examined, and resistant strains were characterized. All 56 isolates collected between 1984 and 1987 were susceptible to all antibiotics tested; 13 (7.4%) of 176 strains isolated between 1989 and 1991 were resistant to streptomycin, sulfisoxazole, and tetracycline. lambda-restriction fragment length polymorphism analysis suggested that the 13 resistant strains belonged to nine different clones. The emerging resistance of E. coli O157:H7 to antibiotics could portend an increased prevalence of this pathogen in food animals that receive antibiotics. Antimicrobial resistance of E. coli O157:H7 could be useful as a rapid epidemiologic marker and as a way to select this pathogen from suspected vehicles of transmission, but this resistance could also complicate therapeutic trials with sulfa-containing antibiotics.

Bacterial Toxins↗
PubMed1994

A prospective study of Shiga-like toxin-associated diarrhea in a pediatric population.

Although population-based studies have shown that children have the highest age-specific incidence of infection with the Shiga-like toxin-producing E. coli (SLTEC), these sporadic case series were not focused specifically on the pediatric age group. We undertook a prospective study to determine the frequency of detection of SLT in an exclusively pediatric population. The study design minimized ascertainment and referral bias by systematically defining the population by the presence of diarrheal symptoms rather than by specific diagnosis, previous submission of stool for culture, or referral to a diarrhea study. All children < 10 years of age hospitalized at a tertiary care pediatric hospital, irrespective of admission diagnosis, were surveyed prospectively at admission and for 2 days thereafter for the presence of defined diarrheal symptoms. From May 1, 1991, to April 30, 1992, 227 patients and 92 age- and season-matched controls were enrolled. Fecal SLT was detected in six (2.6%) patients, three of whom had E. coli O157:H7 organisms were isolated; SLT was not found in any of the controls. SLT was more commonly detected in children 2-10 years of age and in bloody stools. Salmonella was isolated in six (2.6%) cases, Shigella in five (2.2%), and Yersinia in three (1.3%); rotavirus was detected in 46 (20.3%). Two patients with SLT-associated diarrhea had hemolytic uremic syndrome (HUS), and four had hemorrhagic colitis. SLT-associated diarrhea occurred in the summer and fall months in contradistinction to that with rotavirus, which occurred in the winter and spring.(ABSTRACT TRUNCATED AT 250 WORDS)

Bacterial Toxins↗
PubMed1993

Investigation of a unique time-space cluster of sarcoidosis in firefighters.

A unique cluster of three cases of sarcoidosis developed recently among 10 white firefighters who trained together as apprentices in 1979. This led us to hypothesize that firefighters are at increased risk of this condition because of the combined effect of smoke exposure and infection with a communicable agent, such as Chlamydia pneumoniae, a recently proposed cause of sarcoidosis. We conducted a case-finding questionnaire survey of 1,282 active and retired male Providence firefighters and police officers and then evaluated both the index apprenticeship class and two control cohorts by chest radiography, seromarkers of T lymphocyte activation (neopterin and sIL-2R), and chlamydial serology. One additional case of sarcoidosis was identified among the 990 (77%) survey respondents. No new cases were detected in the subsequent laboratory investigation of 46 (87%) firefighters from the index 1979 apprenticeship class, 53 (75%) firefighter controls from the 1974 and 1980 classes, or 50 (30%) police officer controls from 1973-1981 classes. The cohorts did not differ with regard to either C. pneumoniae antibody titers or sIL-2R levels, but serum neopterin was elevated (> 9.0 nmol/L) in 20% (eight of 41) of the index cohort, 22% (11 of 51) of firefighter controls, and 4% (two of 48) of police officers. Logistic regression found firefighting to be the only significant predictor of neopterin elevation (odds ratio 5.8; 95% CI, 1.3 to 26.9). Our results suggest that firefighters may be at risk of T lymphocyte activation. Determining whether this reflects an enhanced risk of lymphocytic alveolitis and whether firefighters are more likely to develop sarcoidosis requires further study.

Adult↗
PubMed1993

A seroepidemiologic study of Chlamydia pneumoniae in Rhode Island. Evidence of serologic cross-reactivity.

OBJECTIVE: Although Chlamydia pneumoniae is considered a common cause of pneumonia worldwide, the evidence is mainly serologic. Therefore, we examined whether the currently used chlamydial microimmunofluorescence (MIF) antibody test is specific for C pneumoniae infection. DESIGN AND SETTING: Secondary analysis of data from a cohort study of sarcoidosis among the graduates of ten consecutive apprenticeship classes of firefighters and police officers. PARTICIPANTS: One hundred forty-seven young adult men. MEASUREMENTS: Immunoglobulin G and M antibodies to C pneumoniae, 15 serovars of C trachomatis, and 2 strains of C psittaci as measured by MIF. RESULTS: Evidence of previous C pneumoniae and C trachomatis infection (IgG > or = 1:16 yet < 1:512) was present in 108 (73 percent) and 59 (40 percent) subjects, respectively. Serologic evidence of recent C pneumoniae and C trachomatis infection (IgM > or = 1:16 or IgG > or = 1:512) was present in 19 (13 percent) and 14 (10 percent) subjects, respectively. Chlamydia pneumoniae and C trachomatis IgM titers were highly correlated (r = 0.80; 95 percent CI, 0.73 to 0.85) while C pneumoniae and C trachomatis IgG titers were fairly correlated (r = 0.44; 95 percent CI, 0.30 to 0.56). CONCLUSIONS: The C pneumoniae seroprevalence of 86 percent is the highest yet reported. The correlations between C pneumoniae and C trachomatis antibody titers suggest that chlamydial MIF may be less specific than is generally appreciated. Moreover, the observed 13 percent seroprevalence of recent C pneumoniae infection in a healthy working population challenges the serologically based belief that this agent accounts for 6 to 10 percent of community-acquired pneumonia. A more objective, more specific test is needed in the serodiagnosis of C pneumoniae infection.

Adult↗
PubMed1992

Avian P1 antigens inhibit agglutination mediated by P fimbriae of uropathogenic Escherichia coli.

Whole egg white from pigeon, dove, and cockatiel eggs, as well as the ovomucoid fraction of pigeon egg white, exhibited strong P1 antigenic activities and inhibited agglutination of human P1 erythrocytes and of digalactoside-coated latex beads by P-fimbriated Escherichia coli strains. In contrast, chicken egg white exhibited only weak P1 antigenic activity and had little impact on P-fimbrial agglutination. These preparations did not affect hemagglutination by E. coli strains expressing mannose-resistant adhesins other than P fimbriae, i.e., Dr, F1845, and S adhesins. Human anti-P1 serum diminished the P-fimbrial inhibitory activities of pigeon egg white and pigeon ovomucoid. Pigeon ovomucoid was equipotent on a molar basis with globoside, and the pigeon, dove, and cockatiel egg white preparations were equipotent with each other in P-fimbrial inhibition. Incubation of p erythrocytes in whole egg whites or in pigeon ovomucoid did not render them agglutinable by P-fimbriated bacteria, whereas incubation in globoside did. These data demonstrate that whole egg whites (and their ovomucoid fraction) from members of the families Columbidae (pigeons and doves) and Psittacidae (parrots) specifically and potently inhibit P-fimbrial agglutination, probably by providing P1 antigen as a receptor for the P-fimbrial adhesin. Avian egg white preparations may facilitate adhesin characterization of wild-type uropathogenic strains and may useful in preventing upper urinary tract infections due to P-fimbriated E. coli.

Adhesins, Escherichia coli↗
PubMed1992

Red storm rising.

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History, 20th Century↗
PubMed1991

Failure of ciprofloxacin to eradicate convalescent fecal excretion after acute salmonellosis: experience during an outbreak in health care workers.

OBJECTIVE: To determine the efficacy of ciprofloxacin therapy in eradicating convalescent fecal excretion of salmonellae after acute salmonellosis. DESIGN: Randomized, placebo-controlled, double-blind trial of ciprofloxacin, with prospective follow-up of nonparticipants. SETTING: An acute care community hospital experiencing an outbreak of salmonellosis. PATIENTS: Twenty-eight health care workers developed acute infection with Salmonella java; 15 participated in a placebo-controlled trial of ciprofloxacin, beginning on day 9 after infection. INTERVENTIONS: Eight patients were randomly assigned to receive ciprofloxacin, 750 mg, and 7 patients to receive placebo; both were administered orally twice daily for 14 days. Nonparticipants who received therapy were placed on the same ciprofloxacin regimen. MEASUREMENTS AND MAIN RESULTS: Study participants had follow-up stool cultures every 3 days initially and then weekly for 3 weeks; nonparticipants were followed until three consecutive cultures were negative. All eight ciprofloxacin recipients showed eradication of S. java from stool cultures within 7 days of beginning therapy (compared with 1 of 7 placebo recipients), and their stool cultures remained negative up to 14 days after discontinuing therapy (P less than 0.01). However, 4 of 8 relapsed; their stool cultures became positive between 14 and 21 days after therapy. In addition, 3 of 3 hospitalized patients treated with ciprofloxacin who did not participate in the controlled trial also relapsed. Thus, the total relapse rate was 7 of 11 (64%; 95% CI, 31% to 89%). In 4 of these 7 patients, relapse was associated with a longer duration of fecal excretion of salmonellae than that of the placebo group. Relapse could not be explained on the basis of noncompliance, development of resistance, or presence of biliary disease. CONCLUSIONS: Despite its excellent antimicrobial activity against salmonellae and its favorable pharmacokinetic profile, ciprofloxacin at a dosage of 750 mg orally twice daily had an unacceptably high failure rate in patients with acute salmonellosis and may have prolonged fecal excretion of salmonellae. The late occurrence of relapses indicates the need to obtain stool cultures up to 21 days after therapy to document fecal eradication in acute salmonellosis.

Acute Disease↗
PubMed1990

Escherichia coli O157:H7 and the hemolytic uremic syndrome: importance of early cultures in establishing the etiology.

Fifty-two patients were studied prospectively to determine the etiology of postdiarrheal hemolytic uremic syndrome (HUS). Escherichia coli O157:H7 was isolated from 33 patients (63.4%). If stool obtained within 2 days of the onset of diarrhea was cultured for E. coli O157:H7, the recovery rate was 100%. This rate decreased to 91.7% and 33.3% if stool was cultured for this pathogen 3-6 or greater than or equal to 7 days, respectively, after diarrhea began. The culture-positive group was more likely to have had bloody diarrhea and fecal leukocytes and to have received transfusions than the culture-negative group but was otherwise similar in clinical characteristics. E. coli O157:H7 is the predominant pathogen associated with HUS in western Washington. Recovery of this pathogen is highly dependent on obtaining stool cultures within 6 days of onset of diarrhea.

Adolescent↗
PubMed1989

Toxin genotypes and plasmid profiles as determinants of systemic sequelae in Escherichia coli O157:H7 infections.

In 1987, 93 Escherichia coli O157:H7 isolates were collected during routine surveillance for this pathogen in the state of Washington. Toxin genotypes and plasmid profiles were correlated with the clinical sequelae of illness in 88 of the 93 patients from whom these strains were isolated. Thirteen plasmid patterns were observed among the 88 tested isolates; four patterns accounted for 82% of the isolates. Genetic probing for Shiga-like toxins (SLT) I and II demonstrated the presence of both genes in 67 (76%), SLT I alone in three (3%), and SLT II alone in 18 (20%). The hemolytic uremic syndrome or thrombotic thrombocytopenic purpura developed in seven (39%) of 18 patients infected with isolates having only the SLT II gene, while these complications occurred in only four (6%) of 70 patients infected with isolates having the other two genotypes (relative risk, 6.8; 95% confidence interval, 1.9, 26.4). This study shows that E. coli O157:H7 isolates systematically collected from a single geographic region over a defined time period exhibit considerable diversity in plasmid content and toxin genotype and that the toxin genotype of the infecting strain may influence the risk of developing microangiopathic sequelae.

Age Factors↗
PubMed1989

The increasing incidence of the hemolytic-uremic syndrome in King County, Washington: lack of evidence for ascertainment bias.

The annual incidence of the hemolytic-uremic syndrome was determined for the well-defined population of King County, Washington, between 1971 and 1986, inclusive, to ascertain temporal trends in the epidemiology of this disease. The average annual incidence rose from 0.69 cases per 100,000 children under age 15 years between 1971 and 1975 to 1.77 cases between 1976 and 1980 and 1.74 cases between 1981 and 1986. The mean hematocrits, platelet counts, and blood urea nitrogen and creatinine concentrations on admission were similar in all periods, as were the mean length of hospital stay and the proportions of patients requiring erythrocyte and/or platelet transfusions and dialysis. These results indicate that the increased incidence of hemolytic-uremic syndrome in childhood has been sustained in King County, Washington, and that this increase is not due to ascertainment bias caused by the diagnosis of less severely ill cases. Further investigations are needed to determine whether this increased incidence is being experienced in other populations and to assess strategies for the prevention of microangiopathic sequelae to hemorrhagic colitis.

Adolescent↗