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Biomedical subjects

M A Menegus

Publications and source records attributed to M A Menegus.

At least 37 records · Page 2Linked to original sources
PubMed1991

Use of multiple markers for investigation of an epidemic of Shigella sonnei infections in Monroe County, New York.

Antibiotic susceptibility patterns, plasmid profiles, and endonuclease restriction analysis of plasmid DNA were used in the investigation of an epidemic of Shigella sonnei infections in Monroe County, New York, in 1988 and 1989. The epidemic peaked during the winter, included the simultaneous transmission of the disease from person to person and from common food sources, and especially affected inhabitants of the poor, inner-city neighborhoods, young children of both sexes, and women. Resistance to ampicillin, tetracycline, or trimethoprim-sulfamethoxazole, encoded in a 70-MDa plasmid, was found in most of the examined isolates. Unexpectedly, isolates from patients involved in a food-borne outbreak exhibited three different antibiotic susceptibility patterns, suggesting deletion of antibiotic resistance determinants in some strains. Antibiograms clearly separated food-borne outbreak-related and non-foodborne outbreak-related strains, distinguished more strains than did the plasmid profiles, and were useful in tracing the dissemination of individual isolates in the community. Restriction endonuclease analysis substantially increased the discriminatory value of plasmid profiles and validated the antibiogram results. The present study illustrates the complexity of epidemics of S. sonnei infections and shows the value of combining different biological markers in the investigation.

Adolescent↗
PubMed1990

Comparison of four methods for testing high-level aminoglycoside resistance in enterococci.

In a prospective study the prevalence of high-level aminoglycoside resistance (MIC greater than or equal to 2,000 micrograms/ml) among 62 clinically significant enterococci was investigated. A total of 10(5) organisms were inoculated a) onto a plate containing 2,000 micrograms/ml of gentamicin or streptomycin; b) into a microtube for dilution MIC determinations for gentamicin, amikacin, tobramycin and streptomycin; and c) into a single tube containing 500 micrograms/ml of gentamicin, amikacin, tobramycin or streptomycin in supplemented Mueller-Hinton broth. In addition, tubes containing 500 micrograms/ml of gentamicin, amikacin, tobramycin or streptomycin were inoculated with five enterococcal colonies ("crude" method). For 45 of the 62 isolates, MICs of gentamicin, amikacin and tobramycin were less than or equal to 500 micrograms/ml, while 17 (27%) showed high-level resistance. The MICs of streptomycin were less than or equal to 500 micrograms/ml for 42 of 62 isolates, and greater than or equal to 2,000 micrograms/ml for 20 (32.3%). For 8 of the 17 (47%) isolates showing high-level gentamicin resistance, MICs of streptomycin were less than or equal to 500 micrograms/ml. There was complete agreement between the results of the plate method, the microtube dilution MIC and the tube inoculated with 10(5) CFU, but the crude method gave discordant results for two isolates. It is concluded that a tube containing 500 micrograms/ml of aminoglycoside is a simple, accurate and inexpensive method for determining high-level aminoglycoside resistance.

Amikacin↗
PubMed1990

Enhanced detection of Candida in blood cultures with the BACTEC 460 system by use of the aerobic-hypertonic (8B) medium.

The blood culture records during the 6-year period 1984-9 were reviewed to compare the performance of the BACTEC aerobic (6B) and aerobic-hypertonic (8B) media for the recovery of Candida spp. and Torulopsis glabrata from blood. There were 137 positive blood culture sets that contained both a 6B and an 8B bottle. Sixty-eight different yeasts were recovered from 65 patients including 35 Candida albicans, 19 C. tropicalis, 6 C. parapsilosis, 4 C. krusei, 1 C. pseudotropicalis and 3 Torulopsis glabrata. The 8B medium detected 120 of the positive cultures (87.6%) and was the only positive medium in 35 (25.6%) sets, while the 6B medium detected 102 positive cultures (74.4%) and was the only positive medium in 17 (12.4%) sets (P less than 0.04). For those sets in which both bottles were positive, radiometric detection occurred first in the 8B bottle in 39 sets and first in the 6B bottle in 11 sets (P less than 0.001). The superior performance of the 8B bottle was not related to the administration of amphotericin B. Cultures of stock strains of C. albicans, C. tropicalis, and C. parapsilosis in 6B and 8B media with and without added blood confirmed the finding that 8B was substantially superior to 6B for the detection of candidaemia. It is concluded that an 8B bottle should be included in the blood culture set whenever candidaemia is suspected.

Aerobiosis↗
PubMed1990

Comparison of epidemic and endemic group G streptococci by restriction enzyme analysis.

Restriction enzyme profiles of group G beta-hemolytic streptococci associated with a point source outbreak and an outbreak of sporadic pharyngitis in two different communities were compared. To asses the epidemiologic utility of this approach for studying group G streptococci, DNA fingerprints of strains responsible for a point source outbreak of pharyngitis associated with the consumption of contaminated food were compared with DNA fingerprints of pharyngeal isolates from children with pharyngitis seen at a pediatric practice during a 6-month period. In each epidemiologic situation, a single strain characterized by a unique restriction enzyme pattern predominated. The results are compatible with the conclusion that human infections could be limited to a few strains of group G streptococci which have the capacity to spread through a given population. The restriction enzyme profiles proved to be a highly specific and precise means of evaluating strain relatedness and of providing further understanding of the epidemiology of group G streptococcal infections.

Connecticut↗
PubMed1990

Cumulative positivity rates of multiple blood cultures for Mycobacterium avium-intracellulare and Cryptococcus neoformans in patients with the acquired immunodeficiency syndrome.

We examined the occurrence of low-grade Mycobacterium avium-intracellulare bacteremia and Cryptococcus neoformans fungemia in patients with the acquired immunodeficiency syndrome and the consistency of positive cultures obtained using a sensitive blood culture system (Isolator, E. I. Du Pont de Nemours, Wilmington, Del) for the recovery of these organisms. The blood culture records were reviewed, and the proportion of positive blood cultures yielding less than 1 colony-forming unit per milliliter of M avium-intracellulare or C neoformans was calculated. To determine consistency, a period of potentially detectable septicemia was defined as the period between 1 week before the first positive blood culture and the last positive blood culture, providing consecutive positive blood cultures were separated by less than 2 weeks. All positive and negative blood cultures obtained during the period of potentially detectable septicemia were considered in the data analysis. Overall, 40 (16.9%) of 236 cultures positive for M avium-intracellulare and 36 (57.1%) of 63 for C neoformans yielded less than 1 colony-forming unit per milliliter. Mycobacteremia was detected in 52 of 57 periods of potentially detectable septicemia in the first culture and in 56 of 57 in the first two (cumulative detection rates of 91.2% and 98.2%, respectively). Cryptococcemia was detected in 12 of 17 periods of potentially detectable septicemia in the first culture and in 15 of 17 in the first two (cumulative detection rates of 70.6% and 88.2%, respectively). Because of the sensitivity of the blood culture system and the consistency of M avium-intracellulare bacteremia and C neoformans fungemia in patients with the acquired immunodeficiency syndrome, it appears that two blood cultures are sufficient for the detection of most septic episodes caused by these organisms.

Acquired Immunodeficiency Syndrome↗
PubMed1990

Semipermeable dressing and transepidermal water loss in premature infants.

Within the first days of life, 10 infants, of 32 weeks' gestational age or less, began 2 weeks of treatment with a semipermeable wound dressing over a small area of skin. The effects of the dressing on transepidermal water loss and cutaneous microflora were evaluated. Transepidermal water loss from the semipermeable dressing-treated skin was significantly less than that from the untreated skin immediately after placement of the dressing (8.1 +/- 1.8 g/m2.h-1 vs 17.7 +/- 3.5 g/m2.h-1, P less than .0001). The normal accelerated skin maturation process that occurs in these infants continued beneath the semipermeable dressing. The number of gram-negative bacilli or other bacteria did not increase beneath the semipermeable dressing beyond that seen on the untreated site. Malassezia furfur was found only on the control site, never beneath the semipermeable dressing. According to results of this preliminary study, a semipermeable dressing can be safely used in premature infants and the use of a semipermeable dressing may decrease the excessive transepidermal water loss associated with prematurity.

Bacteria↗
PubMed1989

Epidemiology and laboratory diagnosis of infection with viral and bacterial pathogens in infants hospitalized for suspected sepsis.

A prospective study was conducted to determine the frequency and distribution of bacterial and viral pathogens in infants hospitalized with suspected sepsis and to evaluate the potential of virus detection for improving patient management. A causative organism was detected in 157 (67%) of 233 previously healthy infants less than 3 months of age, who had been hospitalized for suspected sepsis: 19 (8%) had bacterial infections, 135 (58%) had viral infections, and 3 (1%) had mixed viral-bacterial infections. Viral infections occurred in a seasonal pattern: enteroviruses were responsible for most of the hospitalizations during summer and fall (65/110; 63%) and respiratory syncytial and influenza A viruses were responsible for most of the infections during winter (44/81; 55%). In contrast, bacterial infections were not seasonally distributed. Virus was detected in 33% of the 138 infected infants within 24 hours, and in 64% within 3 days. We conclude that viral infections are prevalent among infants hospitalized for suspected sepsis, and most can be detected early enough to influence patient management.

Bacterial Infections↗
PubMed1988

Enterovirus in pregnant women and the perfused placenta.

A survey of all nonpolio enterovirus infections in adults for a 10-year period revealed that most such infections will occur in the child-bearing age group during the third quarter of the year. Coxsackieviruses occurred more often than echovirus infection. Fourteen pregnant women, including four with meningitis, who had an enterovirus infection from 16 to 37 weeks of gestation delivered uninfected, healthy infants. Attempts to demonstrate transplacental passage of Coxsackie B-3 or ECHO-11 viruses by use of the dual, recirculating, in vitro perfusion of an isolated placental lobule were unsuccessful even with a maternal virus input of 200,000 median tissue culture infectious doses. This suggests that transplacental passage of virus does not occur readily, and that most neonates of infected mothers will be unharmed.

Adolescent↗
PubMed1988

Association of clinical presentation, laboratory findings, and virus serotypes with the presence of meningitis in hospitalized infants with enterovirus infection.

One hundred eight hospitalized infants with enteroviral infections were studied to determine the association of clinical presentation, laboratory findings, and virus serotypes with the presence of meningitis. Of 108 infants, 55 (51%) had meningitis. Clinical manifestations on admission did not distinguish between infants with and those without meningitis. Echoviruses 30 and 11 and coxsackie virus B were frequently associated with meningitis (34/38; 90%) whereas echoviruses 18, 24, and 25 were not (5/35; 4%). The virus isolation rate was directly proportional to the number of leukocytes in cerebrospinal fluid: 5 of 58 (9%) when up to 9 cells/mm3 were found, 10 of 21 (48%) when 10 to 99/mm3 cells were found, and 25 of 29 (86%) when greater than equal to 100 cells/mm3 were found. Meningitis is often unsuspected in children hospitalized with enterovirus infection. The frequency of meningitis among hospitalized infants is serotype dependent and is most frequently, but not exclusively, found with pleocytosis of the cerebrospinal fluid.

Cerebrospinal Fluid↗
PubMed1987

Snow Mountain agent gastroenteritis from clams.

A 1983 investigation of two clambake-related gastroenteritis outbreaks in Rochester, New York, showed that 84 (43%) of 196 persons interviewed had an acute illness characterized by watery diarrhea, vomiting, and abdominal cramps. None of the ill persons were hospitalized or had complications. Illness was associated with eating raw (p = 0.002) or baked (p less than 0.01) hard-shell clams, with the risk of illness increasing with the total number of clams consumed (p less than 0.01). The median incubation period and duration of illness were 36 and 44 hours, respectively. Stool samples obtained 2-4 days after onset of illness were negative for commonly recognized bacterial and viral pathogens. However, of 31 persons whose stools were tested, the stool of only one ill person was positive by enzyme-linked immunosorbent assay for the Snow Mountain agent, one of the Norwalk-like viruses. Paired serum specimens from six (67%) of nine ill and two (29%) of seven well persons showed a fourfold or greater rise in antibody titer to Snow Mountain agent. Persons who ate clams were more likely to seroconvert to Snow Mountain agent (eight of 12) than were those who did not eat clams (zero of four) (p = 0.04). The clams were harvested off the coast of southern Massachusetts in late October, when harvest waters were documented to be contaminated by untreated municipal sewage. This report describes the first documented outbreak of shellfish-associated gastroenteritis attributed to Snow Mountain agent of which we are aware.

Acute Disease↗