Respiratory viral infections are underdiagnosed in patients with suspected sepsis.

The study aim was to investigate the prevalence and clinical relevance of viral findings by multiplex PCR from the nasopharynx of clinically septic patients during a winter season. During 11 weeks of the influenza epidemic period in January-March 2012, consecutive adult patients suspected to be septic (n = 432) were analyzed with cultures from blood and nasopharynx plus multiplex PCR for respiratory viruses on the nasopharyngeal specimen. The results were compared with those from microbiology analyses ordered as part of standard care. During the winter season, viral respiratory pathogens, mainly influenza A virus, human metapneumovirus, coronavirus, and respiratory syncytial virus were clinically underdiagnosed in 70% of patients positive by the multiplex PCR assay. During the first four weeks of the influenza epidemic, few tests for influenza were ordered by clinicians, indicating low awareness that the epidemic had started. Nasopharyngeal findings of Streptococcus pneumoniae and Haemophilus influenzae by culture correlated to pneumonia diagnosis, and in those patients laboratory signs of viral co-infections were common but rarely suspected by clinicians. The role of respiratory viral infections in patients presenting with a clinical picture of sepsis is underestimated. Specific antiviral treatment might be beneficial in some cases and may reduce spread in a hospital setting. Diagnosing viral infections may promote reduction of unnecessary antibiotic use. It can also be a tool for decisions concerning patient logistics, in order to minimize exposure of susceptible patients and personnel.

Rapid identification of pathogenic yeast isolates by real-time PCR and two-dimensional melting-point analysis.

There is a need in the clinical microbiological laboratory for rapid and reliable methods for the universal identification of fungal pathogens. Two different regions of the rDNA gene complex, the highly polymorphic ITS1 and ITS2, were amplified using primers targeting conserved regions of the 18S, 5.8S and 28S genes. After melting-point analysis of the amplified products, the T(m) of the two PCR-products were plotted into a spot diagram where all the 14 tested, clinically relevant yeasts separated with good resolution. Real-time amplification of two separate genes, melting-point analysis and two-dimensional plotting of T(m) data can be used as a broad-range method for the identification of clinical isolates of pathogenic yeast such as Candida and Cryptococcus spp.

Serotypes and clinical manifestations of invasive group B streptococcal infections in western Sweden 1998-2001.

This study monitored the serotypes of Streptococcus agalactiae (group B streptococcus; GBS) isolated from invasive infections in western Sweden and investigated possible relationships between serotype, age and clinical manifestations. Invasive GBS isolates were collected prospectively during 1998-2001 at six laboratories, covering two counties with a population of 1.8 million, and were serotyped by coagglutination. Clinical data were obtained from hospital notes. In total, 161 invasive strains (50 from neonates and infants aged < 3 months, and 111 from adults) were serotyped. The commonest serotypes from neonates and infants were serotypes III (60%), V (22%) and Ia (10%), and from adults were serotypes V (42%) and III (25%). Serotype V had doubled in frequency among both children and adults compared to a previous study from the same area in 1988-1997. Most (80%) of the adults had an underlying medical condition. No relationship was found between serotype and clinical manifestations. However, the study demonstrated the importance of active surveillance of GBS serotypes and the difficulties of formulating a multivalent polysaccharide conjugate vaccine against GBS.

Invasive pneumococcal infections in Southwestern Sweden: a second follow-up period of 15 years.

In a retrospective study, the incidence, clinical manifestations, concomitant conditions and case fatality rate were studied in patients with invasive pneumococcal infections in the Göteborg area of Sweden during 1981-95, when the pneumococcal polysaccharide vaccine was available but little used. Patients were identified from the records of the Departments of Clinical Bacteriology and from the computer-based hospital discharge registers of the relevant departments. Individual case records were found for 876 patients with invasive pneumococcal infections verified by cultures from blood, cerebrospinal fluid or other sterile body fluids. A study from the same area with the same design covering the years 1964-80 has previously been published. There was an increase in total incidence from 5.3 to 10.3 cases/100,000/y from the previous to the present study. This increase was due to an increase in patients with non-meningitic infections aged > or = 60 y. The incidence of meningitis was virtually unchanged (1.4/100,000/y), as was the incidence of non-meningitic infections in individuals < 60 y. There were no other important changes between the 2 studies, which confirm that invasive pneumococcal infections have the highest incidence rates in children < 2 y and in the elderly, that a wide variety of underlying conditions are seen in the patients and that the case fatality rate, 15% in the present study, is still high.

Serotypes and clinical manifestations of group B streptococcal infections in western Sweden.

OBJECTIVES: To study the serotype distributions of group B streptococci (GBS) isolated from blood and cerebrospinal fluid and from the genital tract of pregnant women and to investigate any possible relation between serotype, age and clinical manifestation. METHODS: Invasive strains were collected from 1988 to 1997 and genital strains from 1995 to 1996. Strains of GBS were serotyped with coagglutination. Clinical data were obtained from hospital notes. RESULTS: A total of 144 invasive strains, 78 from neonates and infants and 66 from adults, were serotyped. The most common isolates from neonates and infants were types III (62%), Ia (18%), and V (9%). The most common isolates from adults were types III (29%), Ib (23%), V (21%) and II (15%). A majority of the adults (94%) had an underlying medical condition. The most common serotypes of the 114 strains isolated from the genital tract of pregnant women were types III (32%), V (22%), Ia (13%), Ib (13%) and II (11%). CONCLUSIONS: Serotype III was the single most frequent GBS isolate from infants and adults. Serotype V, which appeared first in 1992, was the third most frequent isolate. A vaccine containing five GBS capsular polysaccharides appears to be appropriate for the Swedish population.

New species-related MIC breakpoints for early detection of development of resistance among gram-negative bacteria in Swedish intensive care units.

The frequency of decreased antibiotic susceptibility among 534 Gram-negative aerobic bacilli from patients admitted to intensive care units at eight hospitals in Sweden during 1997 was evaluated. MICs of cefepime, ceftazidime, ceftriaxone, ciprofloxacin, gentamicin, imipenem and piperacillin-tazobactam were determined using Etest. Reduced susceptibility (resistant and intermediate/indeterminate susceptible strains) was defined according to the MIC breakpoints of the British Society for Antimicrobial Chemotherapy (BSAC), the National Committee for Clinical Laboratory Standards (NCCLS) and the new species-related breakpoints of the Swedish Reference Group for Antibiotics (SRGA). The BSAC/NCCLS/SRGA breakpoints for susceptible category (mg/L) of Enterobacteriaceae are: cefepime, not available (NA)/8/0.5; ceftazidime, 2/8/2; ceftriaxone, NA/8/0.5; ciprofloxacin, 1/1/0.12; gentamicin, 1/4/2; imipenem, 4/4/1; and piperacillin-tazobactam, NA/16/16. The most frequently isolated organisms were Escherichia coli (n = 160; 30%), Klebsiella spp. (n = 84; 16%), Enterobacter spp. (n = 77; 14%), Pseudomonas aeruginosa (n = 64; 12%) andProteus spp. (n = 28; 5%). Decreased susceptibility among E. coliusing the BSAC/NCCLS/SRGA respective breakpoints (%) were: cefepime, NA/0/2; ceftazidime, 2/2/2; ceftriaxone, NA/1/2; ciprofloxacin, 2/2/8; gentamicin, 21/0/3; imipenem, 0/0/2; and piperacillin-tazobactam, NA/4/4. Corresponding levels of decreased susceptibility (%) among Klebsiellaspp. were: cefepime, NA/0/5; ceftazidime, 2/1/2; ceftriaxone, NA/1/10; ciprofloxacin, 4/4/19; gentamicin, 25/2/5; imipenem, 0/0/0; and piperacillin-tazobactam, NA/10/10; and among Enterobacter spp. were: cefepime, NA/1/19; ceftazidime, 30/29/30; ceftriaxone, NA/30/36; ciprofloxacin, 3/3/15; gentamicin,18/0/0; imipenem, 0/0/5; and piperacilllin-tazobactam, NA/27/27. In conclusion, the species-related SRGA breakpoints detected Gram-negative isolates with decreased susceptibility in comparison with the native population with higher frequency than did the NCCLS breakpoints. The BSAC breakpoints for susceptible organisms were similar to NCCLS for ciprofloxacin and imipenem, and similar to SRGA for ceftazidime but lower than both NCCLS and SRGA for gentamicin, causing a much higher frequency of decreased susceptibility to gentamicin.

Studies on a Hib-tetanus toxoid conjugate vaccine: effects of co-administered tetanus toxoid vaccine, of administration route and of combined administration with an inactivated polio vaccine.

A freeze-dried tetanus toxoid (T) conjugated Haemophilus influenzae type b (Hib) vaccine, was reconstituted in either diphtheria toxoid (D), DT or a combined DT and inactivated polio vaccine (IPV), and administered in an open randomized trial either intramuscularly (i.m. ) or subcutaneously (s.c.) to 287 Swedish infants at three, five and 12 months of age. When not included in the mixture, IPV was administered s.c. at a separate site. The geometric mean concentrations of Hib antibodies after primary and booster vaccinations were 1.0 and 11.6 microg/ml, respectively, with no differences related to co-administration of the carrier protein T. Antibodies against T were induced by the T conjugated Hib vaccine (Hib-T) alone in 69/95 infants aged six months, and in 87/93 children aged 13 months, although infants receiving both Hib-T and T had significantly higher concentrations. Antibody responses to Hib, D, T or polio were not negatively influenced by administration route or by mixing with IPV, except that the mixed vaccine DT-IPV induced lower anti-polio GM titers after primary vaccination than did separate IPV. More local reactions were induced by the s.c. than by the i.m. route (P-values from 0.001 to 0.01). Slight increases in rates of local reactions and febrile events (>/=38 degrees C) occurred by order of dose. The low Hib antibody concentrations after the first two doses in this and other Swedish studies are unlikely to be of clinical relevance. The tetanus antibody response from T as a carrier protein alone was not sufficient for basic tetanus immunization, but should be considered in future use of additional T conjugated vaccines.

Safety and immunogenicity of a combined diphtheria-tetanus-acellular pertussis-inactivated polio vaccine-Haemophilus influenzae type b vaccine administered at 2-4-6-13 or 3-5-12 months of age.

METHODS: In an open randomized study we compared the safety and immunogenicity of two schedules for priming and booster vaccinations of infants. A pentavalent combination vaccine, including a lyophilized Haemophilus influenzae type b-tetanus toxoid conjugate vaccine reconstituted with a liquid diphtheria, tetanus, acellular pertussis (pertussis toxoid and filamentous hemagglutinin) and inactivated polio vaccine (DTaP-IPV/Act-HIB; Pasteur Mérieux Connaught, Lyon, France) was administered to 236 Swedish infants either at 2, 4 and 6 months or at 3 and 5 months, and a booster dose was administered 7 months after the last primary dose. Adverse events were monitored by diaries for 3 days after each vaccination and by questions at the ensuing visits. Antibodies against the different vaccine components were analyzed after the primary series of vaccinations, before and after the booster injections. RESULTS: There were no serious adverse reactions, and the rates of febrile events and local reactions were low in both groups. The three dose primary schedule induced higher geometricmean concentrations for all antigens than did the two dose schedule, but there were no differences between the groups in proportions with protective antibody titers against diphtheria, tetanus, Hib and polio or in proportions with certain defined levels of pertussis antibodies. Prebooster results showed a similar pattern, with the exception that the group primed with three injections showed higher proportions of infants with detectable antibodies against polio-virus types 1 and 3. After booster vaccinations there were no differences between the two schedules in geometric mean or in proportions with antibodies above defined antibody concentrations, indicating effective priming from both primary series of vaccinations. Conclusion. The combined vaccine DTaP-IPV/ Act-HIB vaccine was equally safe and immunogenic when administered according to both time schedules studied.

Incidence and prognosis of meningitis due to Haemophilus influenzae, Streptococcus pneumoniae and Neisseria meningitidis in Sweden.

The incidence, concomitant conditions and case fatality rate of Haemophilus influenzae (Hi) and pneumococcal meningitis and of invasive meningococcal infections were studied retrospectively in Sweden (population 8.4 million) for the years 1987-89, the period before vaccination against Hi type b started. A total of 1,019 cases with culture-verified infection were found. The incidence rates per 100,000 per year were 1.8 for Hi meningitis, 1.2 for pneumococcal meningitis and 1.0 for invasive meningococcal infections. The age-specific incidence was highest in the 3-23 months age group for the 3 bacterial species. Pneumococcal meningitis was common in individuals > or = 60 years and meningococcal infections in the age-group 10-24 years. A serious concomitant condition was known in 57% of all patients with pneumococcal meningitis while this was uncommon for the other organisms. The case fatality rate was 2% for Hi meningitis, 24% for pneumococcal meningitis and 10% for meningococcal infections. All 81 pneumococcal isolates which had been serotyped belonged to serotypes in the 23-valent pneumococcal vaccine. Of the meningococcal isolates, 65% belonged to serogroup B. In conclusion, the high incidence of Hib meningitis justifies general Hib vaccination. Development of a vaccine against N. meningitidis group B should have high priority. Furthermore, improved pneumococcal vaccines are needed for patients with predisposing conditions. The currently available pneumococcal polysaccharide vaccine seems to be underused.

Serum antibodies against haemophilus influenzae type b and tetanus at 2.5 years of age: a follow-up of 2 different regimens of infant vaccination.

In 1990-91 we compared 2 Haemophilus influenzae type b (Hib) conjugate vaccines and 2 different regimens of tetanus vaccination, by vaccinating 142 Swedish infants at ages 3, 5, and 12 months, with either PRP-T (the capsular polysaccharide of Hib conjugated to tetanus toxoid) + D (diphtheria toxoid), or with PRP-OMP (PRP conjugated to an outer membrane complex of meningococcus group B) + DT (diphtheria-tetanus toxoid). In this follow-up, antibodies against Hib and tetanus were analyzed in sera from 133 of the children at the age of 2.5 years. Hib antibodies (> or = 0.06 micrograms/ml) were found in 99% of the children of both groups, but 93% of the PRP-T vaccinees had maintained Hib antibodies > or = 0.15 micrograms/ml, as compared with 80% of the PRP-OMP vaccinees (p < 0.05). In 1992, the batch of PRP-OMP was reported to have questionable immunogenicity. Tetanus toxoid (T) antibodies (> or = 0.01 IU/ml) were found in all sera from both groups. All sera with T antibodies < 0.1 IU/ml showed tetanus toxin neutralizing activity. However, only 75% of children vaccinated with PRP-T had T antibodies > or = 0.1 IU/ml, as compared to 97% of children vaccinated with DT (p < 0.001). In conclusion, Hib and tetanus antibodies were well maintained 18 months after primary vaccination, also in the group vaccinated with the batch of PRP-OMP of somewhat low immunogenicity and in the group of infants receiving their primary tetanus vaccination only by the carrier protein of PRP-T.

Dipslide culture in colonic surgery: a tool for assessment of surgical performance and a guide to antibiotic use.

We evaluated a bacterial culture system for the assessment of surgical performance during colorectal operations, and for assessing the impact of selective postoperative antibiotics in contaminated cases. Surgically related infections were recorded and their risk factors were estimated, using univariate and multivariate methods, in 1079 patients undergoing elective colorectal operations. (Study period 1 was prospective, controlled and randomized, and study period 2 was prospective and open). All the patients were given metronidazole, 1 g i.v., at induction of anaesthesia and 12 h postoperatively. The number of colony-forming units (CFU) on an intraoperative dipslide culture was classified as 0, 1-4 or > or = 5 (n = 591, 183 and 305). Patients with > or = 5 CFU were randomized to receive either no further antibiotics or cefuroxime (1.5 g, i.v. every 8 h for 2 days) during the first study period (30 months). During the second period (84 months), all patients with > or = 5 CFU were to be given cefuroxime. Increasing age (p = 0.014), postoperative transfusion of packed red blood cells (p < 0.001), and high bacterial numbers (p < 0.001) were independently associated with infection. Surgeon-related rates of operative bacterial contamination varied between 12 and 50% (p < 0.001). In patients given only metronidazole, the likelihood of infection rose as the density of bacteria in the wound increased according to a sigmoid dose-response curve (5.1, 9.8 and 47.5% with CFU 0, 1-4 and > or = 5, respectively). In the category with > or = 5 CFU, 265 patients were treated with cefuroxime and 23 (8.7%) subsequently had infections [corrected]. Of 40 patients with > or = 5 CFU who did not receive cefuroxime postoperatively, 19 developed infections (p < 0.001, relative risk 5.47; 95% confidence interval 3.29-9.10). In conclusion, dipslide culture can identify patients at high risk of infection after colonic operations. It can be used to assess surgical performance. The addition of postoperative antibiotic cover for aerobic bacteria, detected by the dipslide, reduced the risk of infection more than 5-fold and almost eliminated the risk of contamination.

Moraxella catarrhalis--an uncommon cause of community-acquired pneumonia in Swedish children.

In 284 Swedish children with community-acquired, roentgenologically verified pneumonia, antibodies to Moraxella (Branhamella) catarrhalis were determined in paired serum samples with an enzyme immunoassay using a whole-cell antigen preparation from 10 strains of M. catarrhalis. Only 9 children (3%) had significant increases in antibodies to M. catarrhalis. Among these 9 children, 11-39 months of age, 6 had serologic evidence of concurrent infection with other respiratory pathogens such as S. pneumoniae, non-capsulated H. influenza, RS virus and adenovirus. In 6 (67%) of the 9 children with antibody response and in 74 (27%) of the 275 children without antibody response to M. catarrhalis, nasopharyngeal cultures yielded growth of this bacterium. M. catarrhalis seems to be a common commensal in the upper respiratory tract, but a rare cause of pneumonia in children.

Antibodies against Haemophilus influenzae type b and tetanus in infants after subcutaneous vaccination with PRP-T/diphtheria, or PRP-OMP/diphtheria-tetanus vaccines.

In an open randomized study, serum antibodies against Haemophilus influenzae type b capsular polysaccharide (PRP) and tetanus toxoid were determined in 146 Swedish infants; 75 of them received PRP conjugated to tetanus toxoid (PRP-T) concurrently with diphtheria toxoid vaccine, and 71 received PRP conjugated to an outer membrane complex of Neisseria meningitidis (PRP-OMP) concurrently with diphtheria-tetanus toxoid vaccine. Injections were given subcutaneously at ages 3, 5 and 12 months. One month after the second injection, the PRP-T recipients had a geometric mean (GM) concentration of 0.38 microgram/ml and only 69% had PRP antibodies > or = 0.15 microgram/ml (considered a protective level). In the PRP-OMP group the GM concentration was 0.44 microgram/ml and 85% had PRP antibodies > or = 0.15 microgram/ml. One month after the third injection, 99% of the infants in both groups had PRP antibodies > or = 0.15 microgram/ml, but PRP-T recipients had significantly higher GM concentration than infants vaccinated with PRP-OMP, 10.21 micrograms/ml vs. 1.90 micrograms/ml (P < 0.001). After all three injections the diphtheria-tetanus toxoid vaccine elicited higher GM concentrations of tetanus toxoid antibodies than did the PRP-T vaccine, but both vaccines induced antibodies above the proposed protective level, 0.01 IU/ml. The reason for the lower than expected immunogenicity of the two Haemophilus influenzae type b conjugate vaccines has yet not been established. For PRP-OMP the most probable explanation is the use of a lot of low immunogenicity, but the route of administration also has to be considered.(ABSTRACT TRUNCATED AT 250 WORDS)

Epidemiology of invasive Haemophilus influenzae type b disease in Scandinavia.

In all Scandinavian countries, most invasive Haemophilus influenzae type b (Hib) infections occur before the age of 5 years. The age-specific incidence of Hib meningitis in this age group is 26-35/100,000 per year in Denmark, Norway, Finland and Sweden and about 43/100,000 per year in Iceland. Of the meningitis patients, approximately 60% are younger than 2 years but Hib meningitis also occurs in older children and adults. The case fatality rate is low (1-3%) in children but the rate of neurological sequelae is considerable. The incidence of acute epiglottitis, the other main manifestation of Hib disease, varies considerably. In Sweden, four studies have shown a very high incidence in the age group 0-4 years, 21-34 cases/100,000 population per year compared to only 5-17 in the other Nordic countries. Epiglottitis is more common than Hib meningitis in older children and adults. In Scandinavia the age-specific incidence of all invasive Hib infections could be estimated to be about 50-65/100,000 per year in the most susceptible age group and the risk of contracting invasive Hib disease before the age of 15 years would be about 1/200-300 children.

Dose response study of an inactivated hepatitis A virus vaccine.

In this dose-response study evaluating 3 different doses and 2 time schedules, the highest dose, 25 units of viral protein antigen, induced a seroconversion antibody response against hepatitis A virus (anti-HAV) over 10 mIU in all vaccinees by week 3 after one dose, indicating rapid onset of protective antibody levels. Following the second dose, given 4 weeks later, rising titers were observed for 20 weeks, when the third and final dose of 25 units was given. The GMT of anti-HAV at 24 weeks (before the third vaccine injection) was 398 mIU/ml for the 25-unit dose, compared to 42 and 65 mIU/ml, respectively, for the 12.5 unit and 6.25 unit doses. The third vaccine dose at 24 weeks gave a booster response in all vaccinees, but the increase in titers was most pronounced in the 25 unit group, which had reached a GMT of 6593 mIU/ml when tested 4 weeks later. Side-effects included mainly local reactions and a few cases of mild diarrhoea, and did not differ for the 3 doses studied. In Scandinavia, hepatitis A vaccines will probably be used mainly for vaccination of foreign travellers. This category usually requires a rapid immunization schedule with few doses. Two doses approximately 3-4 weeks apart will probably be accepted by most travellers, and a single dose may provide short-term protection for most individuals. The need and timing for a booster dose will have to be further studied.