PubMed HealthSearch

Biomedical subjects

B Trollfors

Publications and source records attributed to B Trollfors.

At least 19 recordsLinked to original sources

Isotype composition of antibodies to streptococcus group B type III polysaccharide and to tetanus toxoid in maternal, cord blood sera and in breast milk.

Neonates are protected against group B streptococcal (GBS) infections and tetanus by transplacentally transferred serum antibodies. Antibodies of the immunoglobulin (Ig) G, IgM and IgA classes and IgG subclasses to the capsular polysaccharide (CPS) of type III group B streptococci (GBS III) and to tetanus toxoid (TT) were measured in sera from healthy women of fertile age and in paired maternal and cord blood sera from term and preterm pregnancies. GBS III CPS antibodies of the IgG class were found in sera from 97 out of 100 women of fertile age, but only 15 of them had antibodies above the proposed protective level (greater than or equal to 2 micrograms/ml). TT IgG antibodies above the protective level (0.01 units/ml) were found in all sera. The IgG antibodies against GBS III CPS were mainly composed of the IgG2 subclass and to a lesser extent of IgG1. Almost all women had IgG1 antibodies against TT and 40% had IgG4 antibodies. Total IgG and IgG1 antibodies against GBS III CPS were higher in cord blood sera from 37 term neonates than in sera from their mothers whereas IgG2 antibody levels were similar. Total IgG and IgG1 antibodies against TT were also higher in the 20 term neonates tested than in their mothers. In contrast, total IgG and IgG1 to both GBS III CPS and TT and IgG2 to GBS III CPS were lower in cord blood sera from preterm neonates than in sera from their mothers. IgA antibodies to GBS III CPS were detected in 63% of breast milk samples while IgA antibodies against TT were detected in only 4%.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult

Determination of neutralizing antibodies and specific immunoglobulin isotype levels in infants after vaccination against diphtheria.

Serum samples were obtained from 44 infants vaccinated against diphtheria at the ages of 3, 5 and 12 months with an aluminium-adsorbed diphtheria-tetanus toxoid vaccine containing 15 Lf units of diphtheria toxoid. Toxin-neutralizing antibodies (antitoxin) were measured by the Vero cell assay and IgG, IgM and IgA antibodies against diphtheria toxoid by enzyme-linked immunosorbent assay. A neutralizing antibody titer of 10 corresponded to 0.01 IU/ml, the level considered necessary for short-term protection. Geometric mean neutralizing antibody titers at 3, 5, 6, 12, 13 and 30 months were 28, 21, 173, 61, 1076 and 61. All children had titers of greater than or equal to 10 (greater than or equal to 0.01 IU/ml) between 6 and 30 months of age. At 30 months only 48% had titers of greater than or equal to 100 (greater than or equal to 0.01 IU/ml), the level considered necessary for long-term protection. Geometric mean IgG antibody levels were 13, 36, 216, 64, 649 and 57. IgG antibodies significantly correlated with neutralizing titers and predicted neutralizing antibodies above or below 10 and 100 with an accuracy of 96 and 82%, respectively. IgG antibodies could not, however, be used to predict individual neutralizing antibody titers with great accuracy. IgM antibodies were only detected after the third vaccination. IgA antibodies were not detected in any serum sample from ten infants tested. In conclusion, the Swedish vaccination schedule results in protective antibody levels in infants until at least 30 months of age. The decline of the antibody titers indicates a need for further studies to establish the duration of protection.

Animals

Serum antibodies against a 69-kilodalton outer-membrane protein, pertactin, from Bordetella pertussis in nonvaccinated children with and without a history of clinical pertussis.

Serum antibodies against pertactin were found in all samples from 260 nonvaccinated healthy Swedish 1- to 4-year-old children, although 42% had neither a history of clinical pertussis nor antibodies against pertussis toxin or filamentous hemagglutinin. Pertactin antibody levels were, however, higher in children with a history of pertussis than in those without a history of pertussis, and higher in children with antibodies against pertussis toxin and filamentous hemagglutinin than in those without such antibodies.

Antibodies, Bacterial

Characterization of the serum antibody response to the capsular polysaccharide of Haemophilus influenzae type b in children with invasive infections.

The serum antibody response to the capsular polysaccharide of Haemophilus influenzae type b (Hib) was studied in 30 children aged 1 day-5 years with invasive Hib infections. From each child, serum was obtained 0-2 days, 5-11 days, 1 month, and 6-12 months after onset of symptoms. Total antibodies were determined with RIA and isotypes with ELISA. Only 2 children had antibody levels above the estimated protective level (0.15 microgram/mL) in the first serum sample. The antibody response was age dependent with wide individual variations. Children > or = 2 years had increases in IgG, IgM, and IgA antibodies with predominance of IgG. The initial IgG response was IgG1 and IgG2 with predominance of IgG1. In the last serum sample, IgG1 antibodies had decreased while IgG2 antibodies remained unchanged. Only 2 of 7 children < 1 year had a detectable antibody response. The correlation coefficient for total antibodies compared with the sum of IgG, IgM, and IgA was .88 (P < .0001) and for IgG compared with the sum of IgG1 and IgG2 was .97 (P < .0001).

Age Factors

Incidence, serogroups and case-fatality rate of invasive meningococcal infections in a Swedish region 1975-1989.

In a retrospective study of invasive meningococcal infections in Greater Gothenburg, Sweden, 213 cases of culture-verified meningitis or septicaemia were identified during the 15-year period 1975-1989. The annual incidence was 2.0/100,000. Cases were seen in all age-groups with the highest rates in the 0-4 and 15-19 year-old groups, 9.5 and 6.2/100,000 respectively. 20% of the patients were less than 2 years. 91% of the patients had no known risk factors. In only 10 cases (5%) was contact with another case of meningococcal infection known. The main clinical manifestations were meningitis (57%), septicaemia with no sign of focal infection (25%) and septic shock (17%). The case-fatality rate for all the patients was 6.6% and did not change during the 15-year period. One-third of the patients who presented with septic shock died. The serogroup was known for strains from 192 patients. 51% of the strains belonged to serogroup B, 10% to group A and 23% to group C. In conclusion, the incidence of meningococcal infection was low but the relatively high case-fatality rate warrants a search for effective prophylaxis. About 30% of the cases were potentially preventable by the currently available tetravalent (A, C, Y and W135) polysaccharide vaccine, which is immunogenic in children greater than 2 years. Widespread use of antibiotic prophylaxis to close contacts of known cases would not lower the incidence markedly.

Adolescent

Diagnosis of pneumonia by cultures, bacterial and viral antigen detection tests, and serology with special reference to antibodies against pneumococcal antigens.

In a prospective study of the etiology of pneumonia 196 adult patients were included. One of the following criteria was required for diagnosis of pneumococcal pneumonia: isolation of pneumococci from blood; isolation from transtracheal aspirate; isolation from sputum or nasopharynx or detection of capsular antigen in sputum in combination with a significant increase in antibodies against at least one pneumococcal antigen (type-specific capsular polysaccharide, C-polysaccharide, pneumolysin); or increase in antibodies against two pneumococcal antigens. Pneumococcal pneumonia was diagnosed in 63 patients (32%). Other diagnoses were nonencapsulated Haemophilus influenzae isolated from transtracheal aspirates, 9; Mycoplasma pneumoniae diagnosed by serology, 17; Chlamydia psittaci, 6; and viral infections, 42. Twenty-two patients (11%) had evidence of infection with more than one agent. The pathogen could not be determined in 70 (36%). Many patients were given antibiotics before admittance to the study, and in some cases a convalescent serum sample was not available.

Adolescent

Antibody response to outer membrane of noncapsulated Haemophilus influenzae isolated from the nasopharynx of children with pneumonia.

In a prospective study aimed at determining the etiology of community-acquired pneumonia in children nasopharyngeal cultures and paired serum samples were obtained from 336 consecutive children ages 6 weeks to 15 years with pneumonia, 167 hospitalized and 169 outpatients. Results regarding Haemophilus influenzae are reported here. Blood cultures obtained from 127 of the hospitalized patients did not yield growth of H. influenzae. H. influenzae was isolated from the nasopharynx of 88 children. Seventy-three strains were noncapsulated, 2 were type b, 2 were type f and 11 were not serotyped. Paired serum samples were available from 38 children with growth of noncapsulated H. influenzae in the nasopharynx as the only potential pathogen. Sixteen of them responded with significant increases in serum antibodies against outer membrane preparations prepared from their own nasopharyngeal isolates. Thirty-eight age- and sex-matched control children with pneumonia without growth of H. influenzae in the nasopharynx served as controls. Sera from each control patient were tested for antibodies against two strains of noncapsulated H. influenzae. Of those, 4 had significant increases in antibodies against one or both outer membrane preparations. The increases in serum antibodies against the outer membrane of noncapsulated strains of H. influenzae indicate that this organism might be a cause of pneumonia in some children.

Adolescent

Persistence of serum antibodies elicited by Haemophilus influenzae type b-tetanus toxoid conjugate vaccine in infants vaccinated at 3, 5 and 12 months of age.

Eighty-five children received three injections of a vaccine consisting of Haemophilus influenzae type b (Hib) capsular polysaccharide (CPS) conjugated to tetanus toxoid (TT) (Hib-TT) at 3, 5 and 12 months of age according to the vaccination schedule for Swedish children. Diphtheria-tetanus toxoid vaccine was concurrently injected at another site. Two dosages, 7.5 and 15 micrograms, of Hib CPS were studied. No serious reactions occurred. Hib-TT elicited fewer local reactions than diphtheria-tetanus toxoid vaccine. Significant increases in Hib CPS serum antibodies occurred after all injections in both dosage groups with virtually no differences between the two groups. After the first and second injections geometric mean serum antibody concentrations of both dosage groups combined increased to 0.49 and 3.71 micrograms/ml and 81 and 99% of the vaccinees, respectively, had concentrations greater than 0.15 micrograms/ml. After the third dose geometric mean concentrations increased to 13.7 micrograms/ml and all had concentrations greater than 0.15 micrograms/ml. The geometric mean Hib CPS antibody concentrations decreased to 1.24 micrograms/ml 18 months after the third injection, but 97% still had concentrations greater than 0.15 micrograms/ml. The rise of Hib CPS antibodies was mostly in the IgG class. The most pronounced increase was seen in the IgG1 subclass but there were also increase in IgG2 and IgG3. Protective concentrations of TT antibodies were found in all postimmunization sera. In conclusion Hib-TT is safe and immunogenic in infants and should be protective from 6 to 30 months and probably longer thereafter.

Antibodies, Bacterial

Ampicillin-aminoglycoside combinations as initial treatment for neonatal septicaemia or meningitis. A retrospective evaluation of 12 years' experience.

In a retrospective study covering the years 1975-1986, 341 episodes of invasive infections in 338 newborn infants were evaluated. Of the 365 pathogens isolated from blood and/or cerebrospinal fluid, 91% were sensitive to either ampicillin or aminoglycosides or both. Ampicillin resistance was mainly found in very low and low birthweight infants with late-onset infections, in which aerobic Gram-negative rods were common pathogens. In contrast, aminoglycoside resistance was common in early-onset infections, due to the dominance of group B streptococcal infections. The ampicillin-aminoglycoside combination had been given as initial treatment in 189 cases of septicaemia or meningitis. Treatment failed in 36 infections (20%), although all organisms were sensitive to one or both antibiotics. Treatment failed in 6 of 34 patients with meningitis but the failure was not related to ampicillin or aminoglycoside resistance. In conclusion, both in vitro and clinical results show that the ampicillin-aminoglycoside combination can be used as initial treatment of invasive infections in neonates.

Ampicillin