Immunogenicity and safety of MMRV and PCV-7 administered concomitantly in healthy children

OBJECTIVE

We assessed the immunogenicity and safety of a combination measles, mump, rubella, and varicella vaccine (MMRV) (ProQuad [Merck & Co, Inc, West Point, PA]) administered to healthy children concomitantly with a pneumococcal 7-valent conjugate vaccine (PCV-7) (Prevnar [Pfizer, Philadelphia, PA]).

PATIENTS AND METHODS

Healthy 12- to 15-month-old children who lacked vaccination and clinical histories for measles, mumps, rubella, varicella, and zoster but had written documentation of receipt of a 3-dose primary series of PCV-7 were randomly assigned in a 2:1:1 ratio to receive either the MMRV and PCV-7 (group 1), PCV-7 followed 6 weeks later by MMRV (group 2), or MMRV followed 6 weeks later by PCV-7 (group 3). The primary safety analysis was 56 days (28 days after each visit). Immunogenicity was evaluated 6 weeks after each vaccination.

RESULTS

A total of 1027 children were enrolled (group 1: 510; group 2: 258; group 3: 259). For all 3 groups, the antibody response rate was ≥96.8% for measles, mumps, and rubella, ≥88.0% for varicella-zoster virus, and ≥98.3% for all of the 7 Streptococcus pneumoniae serotypes. The immune responses to all antigens present in MMRV and PCV-7 were similar whether administered concomitantly or sequentially. The incidence of local and systemic adverse experiences (AEs) was comparable between group 1 and groups 2 and 3 combined. No vaccine-related serious AEs were reported.

CONCLUSIONS

Concomitant administration of the MMRV and PCV-7 is highly immunogenic and generally well tolerated. Similar immune responses between the groups support concomitant administration of the MMRV and PCV-7 to healthy children 12 to 15 months of age.

Immunogenicity and safety of an inactivated hepatitis A vaccine administered concomitantly with diphtheria-tetanus-acellular pertussis and haemophilus influenzae type B vaccines to children less than 2 years of age

OBJECTIVE

The availability of a hepatitis A virus vaccine for infant and early childhood immunization could reduce the transmission of hepatitis A virus in the United States. This study evaluated the immunogenicity and safety of a hepatitis A virus vaccine (Havrix, GlaxoSmithKline Biologicals, Rixensart, Belgium) administered concomitantly with diphtheria-tetanus-acellular pertussis and Haemophilus influenzae type b vaccines to children < 2 years.

METHODS

In this open, comparative, multicenter study, 1084 healthy children aged 11 to 25 months were allocated (4:4:3:3:4 ratio) to 5 treatment groups based on age and previous vaccination history. Subjects 11 to 13 months of age received 2 doses of hepatitis A virus vaccine 6 months apart (N = 243). Subjects aged 15 to 18 months received 2 doses of hepatitis A virus vaccine 6 months apart (N = 241); or hepatitis A virus vaccine, diphtheria-tetanus-acellular pertussis, and H influenzae type b at month 0 and the second dose of hepatitis A virus vaccine 6 months later (N = 183); or diphtheria-tetanus-acellular pertussis and H influenzae type b at month 0 and hepatitis A virus vaccine at months 1 and 7 (N = 175). Subjects 23 to 25 months of age received hepatitis A virus vaccine at months 0 and 6 (N = 242). Immune responses were measured at baseline and 30 days after vaccine doses, and solicited and unsolicited adverse events were collected.

RESULTS

After 2 doses of hepatitis A virus vaccine, all of the subjects in all of the groups were seropositive. Coadministration of hepatitis A virus vaccine with diphtheria-tetanus-acellular pertussis and H influenzae type b vaccines did not impact the immunogenicity of the 3 vaccines, except for the antipertussis toxoid vaccine response, which was slightly decreased. Hepatitis A virus vaccine was well tolerated in children 11 to 25 months of age.

CONCLUSION

The administration of 2 doses of hepatitis A virus vaccine on a 0- and 6-month schedule starting at 11 to 13 months of age or at 15 to 18 months of age was as immunogenic and well tolerated as the administration of 2 doses in children 2 years of age. Immune responses to diphtheria-tetanus-acellular pertussis and H influenzae type b either given alone or coadministered with hepatitis A virus vaccine were similar except for antipertussis toxoid response.

Evaluation of the measles clinical case definition

An accurate system of identifying and classifying suspected measles cases is critical for the measles surveillance system in the United States. To examine the performance of the clinical case definition in predicting laboratory confirmation of suspected cases of measles, we reviewed 4 studies conducted between 1981 and 1994. A clinical case definition was examined that included a generalized maculopapular rash, fever (>or=38.3 degrees C, if measured), and either a cough, coryza, or conjunctivitis. Serological confirmation of measles was done either by hemagglutination inhibition assay, complement fixation assay, or enzyme immunoassays. The positive predictive value of the clinical case definition decreased from 74% to 1% as incidence decreased from 171 cases/100000 population to 1.3 cases/100000 population. Sensitivity was high, and for the larger studies with the most precise estimates, sensitivity was 76%-88%. The low positive predictive value of the clinical case definition in settings of low incidence demonstrates that serological confirmation is essential to ensure an accurate diagnosis of measles when measles is rare.

Evaluation of a Treponema pallidum-Specific IgM Enzyme Immunoassay and Treponema pallidum Western Blot Antibody Detection in the Diagnosis of Maternal and Congenital Syphilis

BACKGROUND

Congenital syphilis (CS) is a result of untreated or inadequately treated maternal syphilis. CS is more likely with early stages of maternal syphilis, but most mothers lack signs or symptoms and the risk of CS is unclear.

GOAL

The goal of this study was to evaluate Treponema pallidum IgM Western blot (TP IgM WB) and a T. pallidum IgM enzyme immunoassay (TP IgM ELISA) in mothers with syphilis to determine if positive tests better indicate a risk of CS than a rapid plasma reagin titer >/=1:16.

STUDY DESIGN

Ninety-seven mother-baby pairs with reactive syphilis serology were evaluated.

RESULTS

TP IgM WB tests were positive in 18 pregnancies (7 of 18 babies had CS) and negative in 79 pregnancies (7 of 82 babies had CS). Thirty-two mothers had titers >/=1:16 (6 babies with CS) and 65 mothers had titers </=1:8 (8 babies with CS).

CONCLUSION

TP IgM tests better identify mothers at risk of delivering babies with CS than maternal titer >/=1:16.

Phase 2 evaluation of parainfluenza type 3 cold passage mutant 45 live attenuated vaccine in healthy children 6-18 months old

A phase 2 evaluation of live attenuated parainfluenza type 3 (PIV3)-cold passage mutant 45 (cp45) vaccine was conducted in 380 children 6-18 months old; 226 children (59%) were seronegative for PIV3. Of the 226 seronegative children, 114 received PIV3-cp45 vaccine, and 112 received placebo. No significant difference in the occurrence of adverse events (i.e., runny nose, cough, or temperature > or =38 degrees C) was noted during the 14 days after vaccination. There was no difference between groups in the occurrence of acute otitis media or serous otitis media. Paired serum samples were available for 109 of the seronegative vaccine recipients and for 110 of the seronegative placebo recipients; 84% of seronegative vaccine recipients developed a > or =4-fold increase in antibody titers. The geometric mean antibody titer after vaccination was 1 : 25 in the vaccine group and <1 : 4 in the placebo group. PIV3-cp45 vaccine was safe and immunogenic in seronegative children and should be evaluated for efficacy in a phase 3 field trial.

Congenital syphilis and fluorescent treponemal antibody test reactivity after the age of 1 year

BACKGROUND

Many believe that a persistently reactive fluorescent treponemal antibody absorption (FTA-ABS) is manifested with congenital syphilis after the age of 1 year, that it is useful in the retrospective diagnosis of children with congenital syphilis, and that it can be used to confirm other treponemal tests.

GOAL

To determine whether a reactive FTA-ABS after the age of 12 months is indicative of congenital syphilis.

STUDY DESIGN

Prospective outpatient follow-up evaluation until at least the age of 12 months was conducted for 194 babies born to mothers with reactive syphilis serology at delivery, and for two additional children with congenital syphilis diagnosed when they were younger than 1 year (total, 196 children).

RESULTS

In the study group, 54 children had reactive FTA-ABS (reactors) until the age of at least 12 months or more, and 142 children had nonreactive FTA-ABS (nonreactors) at the age of 12 months or more. Of the 54 reactors, 17 (31%) had evidence of congenital syphilis at birth, whereas evidence of congenital syphilis was seen in 14 of the 142 (10%) nonreactors (P = 0.0002). At 15 months, nonreactive FTA-ABS developed in six reactors, and eventually in 15 of 44 reactors (34%) tested.

CONCLUSIONS

A reactive FTA-ABS may be seen at 12 months in children with and without evidence of congenital syphilis at birth. Not all children with congenital syphilis will manifest reactive FTA-ABS at 12 months, and FTA-ABS reactivity wanes with time.

Risk factors for pelvic inflammatory disease in inner-city adolescents

OBJECTIVE

To determine risk factors associated with pelvic inflammatory disease (PID) among inner-city adolescents.

STUDY DESIGN

A case-control study was performed from 1994 to 1997 in an inner-city hospital.

METHODS

Seventy-one adolescent girls diagnosed with PID and 52 sexually active adolescents girls without PID participated in a confidential face-to-face interview using a questionnaire about risk behaviors. Established criteria were used for the diagnosis of PID. Data were analyzed using t tests, chi-square tests, and stepwise logistic regression.

RESULTS

Persons with PID were significantly more likely to show younger age at first intercourse, older sex partners, involvement with a child protection agency, prior suicide attempt(s), consumption of alcohol before last sex, and a current Chlamydia trachomatis infection. There were no significant differences between the two groups regarding number of lifetime sex partners, condom use, rape, syphilis, prior PID, hepatitis B, hepatitis C, or HIV infection.

CONCLUSIONS

Not previously noted in the literature are the association of PID with older sex partners, prior involvement in a child protection agency, and a prior suicide attempt. Confirming prior studies are the association of PID with earlier age at first sex, alcohol use, and C trachomatis infection.

Pediatric imported malaria in New York: delayed diagnosis

The records of 20 children with imported malaria admitted to Kings County Hospital between October 1987 and May 1995 were reviewed. All had a history of recent travel or immigration from a malaria endemic area (West-Africa [16], Central-America [three], and the Caribbean [one]). None of the 10 children with a travel history received appropriate malaria chemoprophylaxis. The most common symptoms and signs were daily fever, chills, and hepatomegaly. Diagnosis was delayed in seven children who were initially felt to have pharyngitis or viral syndrome. Common laboratory findings were anemia and thrombocytopenia. P. falciparum was identified in 70% of the patients. Other species were P. malariae and P. vivax. Complications occurred in six children, hyponatremia in five, seizures in three, and cerebral malaria in one patient. The high incidence of chloroquine-resistant malaria makes chemoprophylaxis difficult in children. The clinical presentation of malaria is nonspecific, and diagnostic delays occur, so a high index of suspicion is needed in children with a travel history.

Obturator internus muscle abscess in children: report of seven cases and review

Obturator internus muscle (OIM) abscess is an uncommon entity often mistaken for septic arthritis of the hip. We describe seven children with OIM abscess and review seven previously reported cases. The most common presenting symptoms were hip or thigh pain (14 patients), fever (13), and limp (13). The hip was flexed, abducted, and externally rotated in 11 patients. Magnetic resonance imaging and computed tomography (CT) were diagnostic for OIM abscess in the 14 patients. Associated abscesses were located in the obturator externus muscle (5 patients), psoas muscle (2), and iliac muscle (1). The etiologic agents were Staphylococcus aureus (8 patients), Streptococcus pyogenes (2), Neisseria gonorrhoeae (2), and Enterococcus faecalis (1). Three patients underwent CT-guided percutaneous drainage, and three had surgical drainage. Three patients had ischial osteomyelitis in addition to OIM abscess. The 11 children with uncomplicated OIM abscess were treated for a median of 28 days. All patients had an uneventful recovery.

Congenital syphilis: detection of Treponema pallidum in stillborns

Paraffin-embedded tissue from all 17 autopsies performed following 56 stillbirths associated with maternal syphilis during a 3-year period (1987-1989) was reexamined to compare immunofluorescent antigen (IFA) testing with silver staining for the detection of Treponema pallidum. Congenital syphilis (CS) originally was diagnosed in 9 of the 17 cases of stillbirth, on the basis of positive silver stains (7 cases) or morphological findings alone (2). Upon review, silver staining revealed T. pallidum in 10 of 17 cases and IFA testing revealed the pathogen in 15 of 17 cases, enabling diagnosis of CS in 16 of 17 cases of stillbirth associated with a reactive maternal rapid plasma reagin (RPR) card test. Most stillbirths associated with a reactive maternal RPR test during this time period involved CS, and IFA testing for T. pallidum is superior to silver staining for the identification of treponemes.

Maternal immunity to measles and infant immunity at less than twelve months of age relative to maternal place of birth

Sera from infants aged 5 to 11 months and from their mothers were used to investigate the level and duration of transplacentally derived measles antibody. The infants of foreign-born, inner-city mothers were more likely to have measles antibody and were less likely to get measles. Infants of foreign-born mothers, because they are less likely to respond to measles vaccine, may require different vaccine strategies than infants of mothers born in the United States.

Maternal and congenital syphilis in Brooklyn, NY. Epidemiology, transmission, and diagnosis

OBJECTIVE

To define the epidemiology, to determine factors associated with transmission, and to describe the clinical and laboratory features of congenital syphilis.

DESIGN

Retrospective chart review and prospective analysis.

SETTING

Kings County Hospital Center, Brooklyn, NY.

PATIENTS

A total of 403 pregnancies during a 23-month period associated with positive syphilis serological findings.

RESULTS

Seventy-three pregnancies (18%) resulted in congenital syphilis (35 live-born and 40 stillborn neonates). Pregnancies associated with congenital syphilis were significantly associated with lack of prenatal care, lack of maternal therapy for syphilis, and a higher rapid plasma reagin titer, but not with a reported history of "crack" or cocaine use, although detection of cocaine in urine samples was more likely with positive syphilis serology.

CONCLUSION

Most live-born infants with congenital syphilis (23 of 35) lacked rash, hepatosplenomegaly, or adenopathy but were identified by laboratory tests (roentgenograms, cerebrospinal fluid VDRL test, conjugated bilirubin determination, or aspartate aminotransferase levels in serum samples). Half of the infants with congenital syphilis were stillborn.

Diagnosis of congenital syphilis by combining Treponema pallidum-specific IgM detection with immunofluorescent antigen detection for T. pallidum

Most infants at risk for congenital syphilis can be identified easily by a positive maternal serologic test for syphilis. However, a diagnosis of congenital syphilis can be difficult to make in an individual infant. Seven infants with delayed-onset congenital syphilis and 101 newborns at risk for congenital syphilis were evaluated for characteristic physical findings and laboratory-detectable abnormalities of congenital syphilis. By using a combination of Western blot for T. pallidum-specific IgM detection and immunofluorescent antigen detection for the identification of T. pallidum, a diagnosis of congenital syphilis was made in all 7 infants with delayed-onset congenital syphilis and 24 of the 101 newborns at risk for congenital syphilis. However, T. pallidum-specific IgM was negative in 6 of the 24 newborns with congenital syphilis. T. pallidum-specific IgM detection alone is inadequate for the diagnosis of congenital syphilis.

Evaluation of prophylaxis against hepatitis B in a large municipal hospital

BACKGROUND

Perinatal transmission of hepatitis B can be interrupted by the administration of hepatitis B vaccine and hepatitis B globulin to the infants of carrier mothers. Universal screening of pregnant women makes this strategy possible.

METHODS

To evaluate the implementation of universal hepatitis B surface antigen screening of women giving birth at Kings County Hospital Center during 1988, we reviewed laboratory records to find all women with a positive test result who might give birth. We also randomly reviewed records of women who gave birth to live infants to determine the percentage of screening in the population. Infants' charts were reviewed for documentation of maternal hepatitis B surface antigen status and administration of hepatitis B immune globulin and vaccine.

RESULTS

Sixty infants who lived long enough to receive antihepatitis B prophylaxis were distinguished out of a total of 5146 births. Screening was done for from 66.8% to 80.4% (95% confidence interval) of the mothers of these infants. Although 44 of 60 infants received hepatitis B immune globulin and 39 of 60 infants received vaccine, only 27 of 60 received vaccine within 12 hours in combination with immune globulin (Centers for Disease Control-recommended therapy).

CONCLUSIONS

Documentation of hepatitis B surface antigen in the infant's delivery room record was present in 23 of 60 infants. Those infants all received hepatitis B immune globulin and vaccine; 21 received hepatitis B immune globulin within 12 hours. Hepatitis B immune globulin was given within 12 hours to 8 of 37 infants who lacked documentation of hepatitis B surface antigen status on the delivery room record. These differences were highly significant (p less than 0.001) even when only the 40 patients who had documented prenatal screening at Kings County Hospital Center (21/23 vs 4/17). Prenatal care did not have any effect on outcome.

Gastric syphilis: five recent cases and a review of the literature

OBJECTIVE

To describe five cases of early syphilis with gastric involvement and to review the literature pertaining to this disorder.

DATA IDENTIFICATION

Five patients were diagnosed with gastric syphilis at Kings County Hospital and the Brooklyn Veterans Affairs Hospital between 1987 and 1990. English-language articles pertaining to gastric syphilis were identified by searching MEDLINE and by manually reviewing bibliographies of retrieved articles.

STUDY SELECTION

Sources containing information pertinent to the clinical manifestations and diagnosis of gastric syphilis were selected.

DATA SYNTHESIS

The most common clinical manifestations of gastric syphilis are abdominal pain, vomiting, and weight loss. Endoscopic findings in the stomach range from minimal nodularity and erythema to deep ulceration. Complications of gastric syphilis include hemorrhage, gastric outlet obstruction, and perforation. The diagnosis can be confirmed by serologic testing and by demonstration of spirochetes on silver and immunofluorescent stains of gastric mucosal biopsy specimens. Response to treatment is usually prompt and complete.

CONCLUSIONS

The current syphilis epidemic will likely result in an increased incidence of gastric syphilis. Unless syphilis is considered as a cause of gastric mucosal inflammation and ulceration, misdiagnosis may delay appropriate treatment, and serious complications can occur.

Comparison of maternal and newborn serologic tests for syphilis

OBJECTIVE

To compare the cord blood, newborn serum, and maternal serum for the diagnosis of congenital syphilis.

DESIGN

Retrospective chart review.

SETTING

Kings County Hospital Center, Brooklyn, NY.

PATIENTS

Three hundred forty-eight mother-newborn pairs with positive syphilis serology.

MEASUREMENTS AND RESULTS

One hundred fifteen newborns (33%) had rapid plasma reagin tests of cord blood that were nonreactive. Their mothers had positive serologic findings. There were 10% false-positive cord blood samples (cord blood rapid plasma reagin tests reactive, newborn serum rapid plasma reagin tests nonreactive) and 5% false-negative cord blood samples (cord rapid plasma reagin tests nonreactive, newborn serum rapid plasma reagin tests reactive). Thirty-three newborns had congenital syphilis. Seven newborns had cord titers fourfold higher than their mothers'; only four of these newborns had congenital syphilis. Maternal serology is superior to cord blood analysis for identifying newborns at risk of congenital syphilis.

Detection of Bordetella pertussis associated with the alveolar macrophages of children with human immunodeficiency virus infection

In humans, infection with Bordetella pertussis is considered to be localized to an epithelial surface. However, an intracellular state in cultured cells and in the macrophages of infected animals has been shown. By using indirect immunofluorescence with a monoclonal antibody, it was found that 3 of 20 bronchoalveolar lavage specimens from children with human immunodeficiency virus infection had B. pertussis associated with pulmonary alveolar macrophages. None of the cultures from the patients grew B. pertussis. The B. pertussis appeared to be intracellular.

Early use of indirect immunofluorescence for the detection of respiratory syncytial virus in HEp-2 cell culture

Respiratory syncytial virus is detected in cell culture by the presence of cytopathic effect. To detect RSV before cytopathic effect is usually seen, slides were evaluated retrospectively from 482 HEp-2 cell cultures on days 2-4 after inoculation. Indirect immunofluorescent staining detected RSV in 57 of 94 cultures that eventually were found positive by cytopathic effect. In an additional 19 cases that ultimately showed no cytopathic effect, RSV also was detected. In 15 of the latter cases, the presence of RSV was confirmed in the original specimen. Use of indirect immunofluorescence can be used to augment the sensitivity of cell culture for the detection of RSV because cytopathic effect may not always be evident.

Failure of recommended maternal therapy to prevent congenital syphilis

A pregnant women with secondary syphilis received appropriate therapy with penicillin in the last trimester of pregnancy. At delivery, her titre had fallen fourfold, and the baby had a non-reactive cord blood titre at birth. However, the treatment failed to prevent infection in the infant, and the baby had developed signs of congenital syphilis at 10 weeks of age. The definition of "adequate therapy" of pregnant women is unclear, and recent guidelines are contradictory. Therefore, literature that pertains to penicillin therapy in pregnancy is reviewed, and new guidelines for therapy proposed.

Pneumococcal C and type polysaccharide detection in the concentrated urine of patients with bacteremia

The C polysaccharide of Streptococcus pneumoniae was detected in the concentrated urine of 23 of 33 patients with pneumococcal bacteremia using latex agglutination. Type-specific polysaccharides were detected in the urine of 17 of these 33 patients including 4 patients lacking C polysaccharide in their urine. These 4 with the 23 detected above gave a total sensitivity of 82% (27/33). The concentrated urine from an additional 11 patients with other bacteremias were tested by C polysaccharide and type-specific reagents and were negative. C polysaccharide detection in the concentrated urine of patients may be helpful in the diagnosis of pneumococcal infections.

Rapid diagnosis of pneumonia in children

Antigen detection techniques are available for the identification of bacterial polysaccharides, viruses, and chlamydia. Viruses and chlamydia are detected by direct immunofluorescence (DFA) or enzyme immunoassay (EIA). Bacterial polysaccharides are detected by latex agglutination or staphylococcal coagglutination of serum or concentrated urine. Most studies have not compared these techniques to the gold standard of lung puncture, so the role of dual infections with bacteria and viruses cannot be adequately determined. The sensitivity of any of these techniques is dependent on the quality of the antisera used. Monoclonal sera are now available for the detection of most viruses and seem to be as sensitive as polyclonal sera. DFA or EIA may offer equal sensitivity but their advantages and disadvantages must be considered by the local diagnostic laboratories. Most DFA and EIA systems have a sensitivity of 90% when compared with viral cultural for the identification of the organism. Agglutination reagents are available commercially for the detection of pneumococcal and Hemophilus influenzae type b polysaccharides. The sensitivity and specificity of each brand should be determined on serum or urine from patients known to have positive blood cultures and those free of disease. The brand chosen should be the one that has reasonable sensitivity and specificity. Rapid diagnostic techniques are helpful if they are used within a clinical context and they are positive. Negative tests do not rule out infection.

Comparison of HEp-2 cell culture and Abbott respiratory syncytial virus enzyme immunoassay

Respiratory syncytial virus (RSV) is the leading cause of lower respiratory tract infection in children. Rapid identification of RSV infections would allow for specific chemotherapy. We evaluated a means of rapid diagnosis, the Abbott enzyme immunoassay (EIA), by using 314 stored nasopharyngeal aspirates. RSV antigens were identified in 62 of 66 RSV culture-positive specimens. An additional 37 specimens from which RSV was not isolated were positive in the EIA. Of these, 29 were confirmed as truly positive by a blocking assay, for a total of 95 (66 + 29) positive specimens. The sensitivity of the EIA for total positive samples was 96% (91/95) versus 69% (66/95) for cell culture. The specificity of the EIA was 96% (211/219). In these stored specimens, Abbott EIA was superior to cell culture for the detection of RSV.

Accuracy of immunoglobulin M immunoassay for diagnosis of chlamydial infections in infants and adults

An improved solid-phase enzyme immunoassay (EIA) with Chlamydia trachomatis L2 434/Bu elementary bodies was developed for the measurement of immunoglobulin M (IgM) antibody to C. trachomatis in serum. Comparison of EIA and microimmunofluorescence IgM antibody titers of 156 serum samples revealed an EIA sensitivity and specificity of 100% for infants, but reduced sensitivity (85%) and specificity (76%) for sera from adults. Sera containing IgM class rheumatoid factor produced false-positive IgM results which could easily be eliminated by pretreatment of the sera with anti-human IgG. Analysis of sera from infants with chlamydial infections revealed that 17 of 17 infants with C. trachomatis pneumonia had high IgM antibody titers (geometric mean titer, 1:64,812), whereas two infants with conjunctivitis only lacked detectable IgM antibody. EIA detected IgM antibody to several serovar groups in serum, including serovars B, BDE, FG, and J. IgM antibody to C. trachomatis in serum was detected as early as 5 days after the infection that was acquired at delivery and persisted for 3 months. The availability of an EIA possessing good sensitivity and specificity for the detection of IgM antibody to C. trachomatis may permit more laboratories to diagnose perinatal chlamydial infections.

Group B streptococcal polysaccharide detection in the urine of neonates by staphylococcal co-agglutination

Staphylococcal co-agglutination reagents were prepared by the sensitization of commercially available staphylococci with commercially available grouping serum. The reagents were able to detect from 31 ng/ml to 62.5 ng/ml of purified group B polysaccharide lacking type specificity, when 20 microliters of polysaccharide solution was used. The reagents were able to identify group B streptococcal polysaccharide in the concentrated urine of all six patients with positive group B streptococcal blood cultures (sensitivity = 100%). Two of 72 patients with negative blood cultures had positive tests when concentrated urine was tested (specificity = 97%). Prepared reagents had a sensitivity and specificity similar to that reported by others for commercially available reagents for the detection of group B polysaccharide at five to ten percent of the total cost.

Evaluation of clinical specimens for the presence of respiratory syncytial virus antigens using an enzyme immunoassay

An enzyme-linked immunoassay (EIA) was developed for the detection of respiratory syncytial virus (RSV) antigen in nasopharyngeal secretions. This assay, which employs goat and rabbit anti-RSV as the capture and detector antibodies respectively, was used in a retrospective evaluation of frozen clinical specimens from children. The EIA results were compared with those of virus isolation in cell culture and direct fluorescent antibody staining performed at the time of specimen collection. The sensitivity of the RSV EIA compared to cell culture was 91.3% (63/69) with a specificity of 96.8% (93/96). The predictive value of a positive EIA result was 95.4% and for a negative EIA result, 93.9%. The sensitivity of the RSV-EIA compared to direct FA was 91.5% (43/47) with a specificity of 96.5% (83/86). These data represent the preclinical evaluation of the Abbott RSV-EIA. This assay could prove to be a useful alternative to virus isolation or direct FA for the diagnosis of RSV infection.

Comparison of ortho respiratory syncytial virus enzyme-linked immunosorbent assay and HEp-2 cell culture

Two hundred seventy nasopharyngeal aspirates were tested in duplicate with the Ortho Diagnostics, Inc. (Raritan, N.J.), respiratory syncytial virus antigen enzyme-linked immunosorbent assay. The test was sensitive (80 to 82%) and specific (96%) when compared with cell culture. The enzyme-linked immunosorbent assay detected seven antigen-positive specimens not among the 71 specimens that were positive for respiratory syncytial virus in cell culture. A blocking test confirmed those specimens as true positives (specificity, 100%).

Comparison of immediate and delayed inoculation of HEp-2 cells for isolation of respiratory syncytial virus

Immediate inoculation of HEp-2 cells is generally advocated for the isolation of respiratory syncytial virus. However, delayed laboratory inoculation of properly transported specimens obtained by aspiration of nasopharyngeal mucus provided an isolation rate similar to that obtained with immediate inoculation.

Inability of counterimmunoelectrophoresis to detect echovirus in cerebrospinal fluid

Methods for rapid detection of viral antigens in cerebrospinal fluid (CSF) are needed to aid in the differentiation of viral from bacterial meningitis. The formation of precipitin bands in patients with suspect viral meningitis utilizing viral antisera in a counterimmunoelectrophoresis (CIE) system has been described. To investigate further the possible value of CIE in the diagnosis of viral meningitis, the specificity of the CSF precipitin bands was studied. Precipitin bands were formed between commercially available type-specific antisera and cell culture supernatant fluids. Precipitin bands were also formed when control CSF was used as an antigen. Using type-specific antisera produced against purified virus, enteroviral antigens were not detected in CSF from patients from whom CSF viruses had been isolated. CIE lacks sufficient sensitivity for the detection of echovirus 11 antigens in CSF.