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G A Storch

Publications and source records attributed to G A Storch.

At least 91 records · Page 5Linked to original sources
PubMed1987

Monoclonal antibodies demonstrate heterogeneity in the G glycoprotein of prototype strains and clinical isolates of respiratory syncytial virus.

In order to study variation among prototype strains and clinical isolates of respiratory syncytial (RS) virus, four prototype strains (Long, A2, CH18537, 9320) were used to produce monoclonal antibodies to this virus. The majority of monoclonals reacted with all four prototype strains by fluorescent antibody staining. Among the non-cross-reacting monoclonals, five additional patterns of reactivity with the prototype strains were recognized. Fourteen monoclonals, including ones representative of each of the patterns of reactivity with the prototype strains, were selected to use for typing prototype strains and community isolates. All 14 were found by immunoprecipitation to recognize the RS virus G glycoprotein. These monoclonals could uniquely identify each of the prototype strains. In addition to the antigenic differences among the prototype strains detected by the monoclonals, differences were also detected in the migration of the G glycoprotein of the prototype strains in polyacrylamide gel electrophoresis. Fluorescent antibody staining with panels of monoclonals distinguished two antigenic types among 114 isolates of RS virus recovered from children in St. Louis during the period 1981-86. The predominant type (80% of isolates) had a pattern of reactivity that resembled but differed from that of either the Long or A2 strains. The second type had a pattern of reactivity identical with that of 9320. The possible significance of this heterogeneity must be considered in developing diagnostic tests as well as active or passive immunotherapy for infections caused by RS virus.

Antibodies, Monoclonal↗
PubMed1987

Methicillin-resistant Staphylococcus aureus in a nursing home.

During a 13-month period, 25 residents of a nursing home were found to have positive cultures for methicillin-resistant Staphylococcus aureus (MRSA), including 17 with clinically significant infections. The outbreak came to attention in February 1985 when pneumonia was diagnosed in five residents during a 10-day period, and sputum cultures from all five were positive for MRSA. A survey revealed that nine (12%) of a sample of 74 residents and nine (7%) of 130 personnel had positive cultures for MRSA. Six of nine residents with MRSA detected in the culture survey had not been hospitalized for 6 or more months before the survey, suggesting acquisition of MRSA in the nursing home. Implementation of control measures was associated with a decreased occurrence but not complete elimination of new cases. MRSA in nursing homes is of concern because these institutions might serve as reservoirs for MRSA in the community. Further studies are required to define the magnitude of the problem, as well as optimal control measures.

Aged↗
PubMed1987

Evaluation of new commercial enzyme immunoassay for rotavirus detection.

We evaluated a new commercial enzyme immunoassay (EIA) for rotavirus (Rotavirus EIA; International Diagnostic Laboratories, Chesterfield, Mo.). A total of 161 consecutive stool samples (including 18 from infants less than 30 days old) submitted to the diagnostic laboratory at Children's Hospital, Washington University Medical Center, St. Louis, Mo., for rotavirus detection were tested by Rotavirus EIA and by Rotazyme II (Abbott Laboratories, North Chicago, III.) according to the instructions of the manufacturer. In addition, 16 samples from infants less than 30 days old without diarrhea were tested by both assays. Samples showing discrepant results after repeat testing were examined by electron microscopy. Nine samples yielding discrepant results were also tested by using a reference EIA directly on the specimen and on culture supernatants from two passages in MA 104 cells. Rotavirus EIA and Rotazyme II yielded concordant results for 85% of the samples. All of the 26 discrepant samples tested negative by Rotavirus EIA and positive (15 samples) or equivocal (11 samples) by Rotazyme II. These samples included 11 from symptomatic infants more than 30 days old, 2 from symptomatic infants less than 30 days old (neonates), and 2 from neonates without diarrhea. Rotavirus was not detected in any of the 24 that were examined by electron microscopy or in any of the 9 that were tested by the reference EIA. The sensitivity, specificity, positive predictive value, and negative predictive value were 100% for Rotazyme EIA and 100, 90, 70, and 100%, respectively, for Rotazyme II. Rotavirus EIA was comparable to Rotazyme II in ease of performance. We conclude that Rotavirus EIA is equally sensitive and more specific than Rotazyme II for detecting rotavirus. Rotavirus EIA is a practical and accurate rotavirus assay for use in clinical laboratories.

Diarrhea, Infantile↗
PubMed1985

A rubella outbreak among dental students: description of the outbreak and analysis of control measures.

From February to April 1982, rubella was diagnosed in 17 Washington University dental students. The affected students represented 4.8% of all dental students and 21% of susceptible students. Because a high likelihood of rubella transmission was perceived, three adjacent university hospitals undertook an emergency program to ensure immunity to rubella in all personnel. The program reached 84.6% of all target personnel, but only 36% of physicians (p less than 0.001). We estimated that the program increased the level of rubella immunity from 92.2% to 98.1%, at a total cost of $140,274 of which $29,990 was in excess of ordinary expenditures. Our experience indicates that schools training health professionals face the possibility of rubella outbreaks unless they ensure rubella immunity in all students. The experience also supports the value of ongoing programs to ensure rubella immunity in hospital personnel. Without such programs, hospitals may be forced to undertake emergency programs that are likely to be disruptive and expensive and may have relatively little immediate measurable impact.

Antibodies, Viral↗
PubMed1985

Comparison of methods for serotyping isolates of Haemophilus influenzae.

This study compared four methods for serotyping isolates of Haemophilus influenzae. Slide agglutination with commercial antisera (Difco Laboratories and Wellcome Diagnostics), coagglutination (Phadebact Haemophilus Test [Pharmacia Fine Chemicals]), latex agglutination with affinity-purified anticapsular antibody, and counterimmunoelectrophoresis with multiple antisera were used to serotype 80 isolates of H. influenzae. Coagglutination and counterimmunoelectrophoresis correctly identified all 80 isolates as either type b or not type b. Slide agglutination and latex agglutination each successfully identified 76 of the 80 isolates; however, each of these two methods failed to type four isolates because of agglutination of controls. We recommend slide agglutination or coagglutination as the serotyping methods of choice in most laboratories because they are simple, accurate, and rapid. Slide agglutination with Difco antiserum can be performed at the lowest cost.

Agglutination Tests↗
PubMed1985

Preparation of urine samples for use in commercial latex agglutination tests for bacterial antigens.

The use of latex agglutination (LA) tests for bacterial antigen detection in urine specimens is hindered by troublesome reactions such as nonspecific agglutination. Therefore, procedures such as boiling or membrane filtration of urine specimens are often used before LA testing. We discovered that the composition of the membrane filter used in filtration has a marked effect on the performance of an LA test used for detection of Haemophilus influenzae type b antigen. False-positive LA reactivity was common in urine specimens from pediatric patients that were processed by membrane filtration through certain filters; furthermore, such reactivity also occurred in LA tests for antigens other than those of H. influenzae. A protein present in urine at low concentrations appeared to be responsible for these phenomena.

Antigens, Bacterial↗
PubMed1985

Prevalence of hepatitis B antibodies in personnel at a children's hospital.

Antibody to hepatitis B core antigen and antibody to hepatitis B surface antigen were measured in serum samples from 825 personnel at St Louis Children's Hospital (702 were possibly at high risk of occupational hepatitis B virus (HBV) exposure and 123 were office personnel); 5.6% had positive findings for both antibodies, 5.6% had findings for antibody to hepatitis B surface antigens alone, and 1.3% had positive findings for antibody to hepatitis B core antigens alone. The group with positive findings for antibody to hepatitis B surface antigens alone did not have traditional risk factors for HBV infection, suggesting that this serologic finding may not be a reliable indicator of past HBV infection. After accounting for the effects of age, sex, and ethnicity, it was found that no occupational group had a significantly increased prevalence of HBV antibodies compared with prevalence in other personnel. In comparison with volunteer blood donors, only physicians older than 40 years of age had an increased HBV antibody prevalence. It is concluded that St Louis Children's Hospital has not been a high-risk environment for HBV exposure in recent years. However, caution is advised in generalizing these conclusions because other children's hospitals may serve a patient population at higher risk of HBV infection. Decisions regarding HBV immunization policy should take into consideration the fact that personnel at different hospitals may face markedly different risks of HBV exposure.

Adult↗
PubMed1984

Latex-agglutination test for rubella antibody: validity of positive results assessed by response to immunization and comparison with other tests.

A commercial-latex agglutination (LA) assay ( Rubascan , Hynson , Westcott and Dunning, Baltimore, Md) performed on undiluted serum may be more sensitive than is the standard hemagglutination-inhibition assay for the detection of rubella antibody. To investigate whether a positive result of an LA test on undiluted serum was correlated with rubella immunity, we identified 29 persons whose sera produced negative results when initially tested by LA at a 1:10 dilution; 15 of these sera produced positive results and 14 produced negative results when retested undiluted. The immune status of each person for rubella was determined with a test for IgM rubella antibody on serum samples obtained three to five weeks after rubella immunization. None of the 15 persons whose preimmunization sera produced positive results by LA when tested undiluted developed IgM rubella antibody, as compared with 10 of the 14 persons whose preimmunization sera produced negative results (P less than 0.001). Data from this study support the specificity of a positive result of an LA test performed on undiluted serum, but a 1:5 dilution may be optimal for determination of rubella immune status.

Adolescent↗
PubMed1984

Survey of hepatitis B viral markers at a public day school and a residential institution sharing mentally handicapped students.

The prevalence of hepatitis B virus markers was studied among employees and clients at a nonresidential public school for the mentally handicapped and at a privately operated residential facility. In the residential institution, 73 (80%) of 91 clients and 15 (16%) of 92 workers had positive tests for hepatitis B virus markers. Twenty-three clients, including six carriers of hepatitis B surface antigen (subtype ayw), received their education their education at the public school. Only two students (4%) who did not live at the residential institution and one employee (2%) had positive tests for hepatitis B virus markers. One of these students had acute hepatitis B infection, with hepatitis B surface antigen subtype ayw; the subtyping suggested that he had acquired the infection from one of the six carriers from the residential institution. Testing for IgM antibody to hepatitis B core antigen in single serum samples facilitated the identification of acute and chronic hepatitis B infection in children and staff of both facilities. The results show hepatitis B can be transmitted in this setting, and vaccination may be warranted for susceptible students and staff.

Adolescent↗
PubMed1984

Control of a rubella outbreak in a dental school population.

This study traces the development of a rubella outbreak; 16 clinical and one sub-clinical case were detected. Overall, the incidence of infection was higher for males than females. Susceptibility rates determined by the absence of primarily IgG antibodies indicated that class association, social contact, and preexisting susceptibility patterns influenced the differences in attack rates seen among the classes. In spite of a higher susceptibility caused in part by the number of foreign students enrolled, no infections occurred in the graduate student population. Concern for the spread of rubella to susceptible students and personnel within the dental school, among adjunct dental assistant and hygiene programs and others at the adjacent medical school and hospitals, led to a comprehensive immunization policy. All dental and medical personnel, regardless of clinical contact, must present proof of immunity or be immunized.

Disease Outbreaks↗
PubMed1982

Use of conventional and IgM-specific radioimmunoassays for anti-hepatitis A antibody in an outbreak of hepatitis A.

During a common source outbreak of hepatitis A, we studied the characteristics and utility of commercially available radioimmunoassays for total and IgM-specific antibody to hepatitis A virus. IgM hepatitis A antibody was detectable in all serum specimens obtained up to 119 days following onset from the seven persons with hepatitis A, and as long as 347 days in one person. Acute infection could also be documented by a four-fold or greater increase in titers of hepatitis A antibody, although as long as nine weeks was required between the times acute and convalescent specimens were obtained. The radioimmunoassay for IgM-specific hepatitis A antibody had greater specificity (99 percent versus 84 percent) and a higher positive prediction value (88 percent versus 23 percent) for the diagnosis of acute hepatitis A than did the radioimmunoassy for hepatitis A antibody. Uses of the radioimmunoassay for IgM-specific hepatitis A antibody include rapid diagnosis of acute hepatitis A, differentiation between recent and past hepatitis A infection, and screening for recent hepatitis A infection in epidemiologic investigation.

Adult↗
PubMed1981

The chest roentgenogram in sporadic cases of Legionnaires' disease.

We reviewed chest roentgenograms from 17 persons with confirmed Legionnaires' disease. None of the cases was associated with known outbreaks. Pulmonary infiltrates, usually extensive, were present in all cases. The predominant radiological pattern of both on initial roentgenograms and those from the peak of illness was distal air space disease, usually in a segmental or lobar distribution. The lower lobes were involved most frequently. Pleural effusion and volume loss were infrequent. Radiological findings progressed rapidly and often cleared rapidly, although slow clearing was also seen in some cases. Legionnaires' disease should be included in the radiological differential diagnosis of segmental or lobar pneumonia.

Adult↗
PubMed1981

Antibiotic-induced lysis of enterococci.

Enterococci are resistant to penicillin killing in vivo and in vitro. Because some bacteria resistant to penicillin killing have reduced autolytic activity, we examined the lysis of clinical enterococcal isolates suspended in buffer (spontaneous lysis), and compared it with their susceptibility to antibiotic-induced lysis and killing. We found significant correlations between spontaneous and antibiotic-induced lysis, using five antibiotics that inhibit cell wall synthesis (penicillin, cephalothin, bacitracin, cycloserine, and vancomycin). Among isolates, strains more rapidly lysed by one antibiotic were more rapidly lysed by the other antibiotics, and more susceptible to spontaneous lysis. In studies involving a single strain grown in different media, spontaneous lysis also correlated closely with antibiotic-induced lysis. These results are consistent with a common mechanism for spontaneous and antibiotic-induced lysis, such as the autolytic enzyme system. Human serum was one of the least permissive media tested for enterococcal growth and antibiotic-induced lysis and killing. We suggest that the inhibitory effect of human serum on growth and the activation of the enterococcal autolytic enzyme system may be a critical factor in the resistance of enterococcal endocarditis to treatment with penicillin alone.

Anti-Bacterial Agents↗
PubMed1980

Shigellosis in the Marshall Islands: epidemiologic aspects of an outbreak.

An outbreak of diarrheal illness caused by Shigella flexneri 1b and associated with 11 deaths occurred in the Marshall Islands during June and July 1977. A house-to-house survey on Majuro indicated an attack rate of 6.2%. Neither the survey nor a case-control study uncovered a common source of exposure on Majuro, and it is believed that transmission was mainly person-to-person. Socioeconomic factors, type of water supply, distance to municipal water supply, and type of sanitary facility could not be related to the occurrence of illness, but a poor sanitary rating was associated with increased rate of household transmission. Absence of stool culturing for bacteria and false-positive identifications of amebae in stool specimens led to the outbreak's being attributed to Entamoeba histolytica. Subsequent parasitologic examinations and serologic studies indicated that E. histolytica played no role in the outbreak, and suggested that fecal leukocytes were being mistaken for amebae. Improved bacteriologic capabilities will be important in improving the approach to diarrheal illness in the Marshall Islands.

Adolescent↗
PubMed1979

The epidemiology of influenza B in a rural setting in 1977.

An epidemic of influenza B began in January, 1977, in two rural parishes in northeastern Louisiana and quickly spread to involve 29% of their population with clinical influenza. This epidemic was investigated using a standard questionnaire and a random sample of 4.2% of the population. The clinical illness was typical of influenza, with predominant fever, cough, malaise and headache. Gastrointestinal symptoms were part of the clinical syndrome. Rhinitis and diarrhea were significantly more common in children aged five years or less. Clinical attack rates increased with larger household size. The youngest age groups had clinical attack rate of 40--55%, but the elderly had very low attack rates. The direct cost of influenza-like illness during the epidemic averaged almost $30.00 per case. Knowledge of the cost of influenza-like illness and age-specific attack rates should be useful in planning future control efforts for influenza B.

Adolescent↗
PubMedDate not supplied

Optimizing recovery of cytomegalovirus in the shell vial culture procedure.

We have investigated three factors that may be related to the recovery of cytomegalovirus (CMV) using the shell vial culture procedure. First, we compared fluorescent-antibody staining of shell vial cultures using a monoclonal antibody to a CMV immediate early antigen at 16 vs 40 hr after inoculation. Of 332 routinely submitted specimens cultured in duplicate and stained at the different times, 25 (7.5%) were positive at 16 hr and 32 (9.6%) were positive at 40 hr. The increased yield was 28%. Second, we analyzed the effect of using duplicate shell vials (both stained at 40 hr) for all routinely submitted CMV cultures. During a 6-month period, 272 (12.5%) of the 2157 cultures processed with duplicate shell vials were positive, including 222 positive in both vials and 50 positive in only one. Assuming that a single-vial setup would have detected 50% of those positive in only one of the two vials, the increased yield attributable to the duplicate vial was estimated at 10% (25/(222 + 25)). Third, we investigated the effects of seeding density and culture age on the shell vial assay. Cell age of greater than 1 day was associated with a decrease in sensitivity both in cultures that were confluent and in those that were subconfluent at the time of inoculation. Incorporating these findings in the routine shell vial culture procedure used in our Clinical Virology Laboratory has resulted in a greater overall detection of CMV in shell vial cultures than in conventional 6-week tube cultures.

Cell Line↗
PubMedDate not supplied

Evaluation of the pediatric Septi-Chek blood culture system.

The pediatric Septi-Chek blood culture system is a biphasic system that uses a 20-ml bottle of brain-heart infusion broth. We compared this system with a supplemented peptone broth tube (Vacutainer) for the recovery of aerobic organisms from blood cultures obtained from patients in a pediatric hospital. Blood specimens for culture were drawn into transport tubes containing sodium polyanetholsulfonate (SPS), and equal volumes were allocated into a Septi-Chek bottle and a Vacutainer tube which was vented for the first day of incubation. A total of 4828 blood culture sets was included, from which 243 probable pathogens were recovered, including 211 in the Septi-Chek system and 204 from the Vacutainer Tube. There were no significant differences in the recovery of individual pathogens. The mean time to initial detection of pathogens was comparable in the two systems, but the mean time to growth on solid media for pathogens recovered in both systems was shorter with Septi-Chek (37.2 hr compared with 45.5 hr, p less than 0.001). The pediatric Septi-Chek system is comparable with a vented Vacutainer tube for the recovery of aerobic pathogens, and its use facilitates the early identification and susceptibility testing of bloodstream pathogens.

Bacteremia↗