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H Peltola

Publications and source records attributed to H Peltola.

At least 19 recordsLinked to original sources

Rapid disappearance of Haemophilus influenzae type b meningitis after routine childhood immunisation with conjugate vaccines.

Mortality from meningitis caused by Haemophilus influenzae type b (Hib), a disease that affects mainly infants and young children, can reach 5% in industrialised countries and ten times that in non-industrialised countries. To determine the efficacy of vaccination against Hib, we carried out a retrospective survey of the incidence of Hib meningitis over five decades in the Greater Helsinki area of Finland, where all children with bacterial meningitis are treated in one of three centres. Except for a meningococcal epidemic in the early 1970s, Hib was the leading cause of childhood bacterial meningitis until the Hib conjugate vaccines changed the picture profoundly. In 1986-87 the polysaccharide-diphtheria toxoid conjugate (PRP-D) was given experimentally to 50% of infants. In 1988-89 all infants were vaccinated, 50% with PRP-D, 50% with another conjugate vaccine, the oligosaccharide-CRM197 protein conjugate (HbOC). Since 1990 a third conjugate vaccine, the polysaccharide-tetanus toxoid (PRP-T), has been administered routinely to all infants. The vaccines were administered at age 3-6 months, with a booster dose at 14-18 months. In the first 5 years of the Hib vaccination programme the number of cases of Hib meningitis in children aged 0-4 years fell sharply, from 30 in 1986 (the first year of the programme) to none in 1991. The decline contrasts sharply with the rising trend up to the mid 1980s. Vaccination seems to be the only explanation for the observed change in the epidemiology of Hib meningitis.

Adolescent

Finnish efficacy trials with Haemophilus influenzae type b vaccines.

The first Finnish trial with Haemophilus influenzae type b vaccine was conducted during 1973-1974. It demonstrated that the polysaccharide vaccine was 90% efficacious in children greater than or equal to 18-24 months old. The immunologically superior polysaccharide-protein conjugate vaccines have been used since 1986 in randomized trials. The PRP-D vaccine (polysaccharide conjugated to diphtheria toxoid) was 90% efficacious when given at 3, 4, and 6 months of age to 58,000 infants. In 1988-1989, the PRP-D vaccine was compared with the HbOC vaccine (oligosaccharide conjugated to CRM197 protein). Follow-up is continuing, but both vaccines seem to be efficacious after two doses in infancy.

Antibodies, Bacterial

Seasonal variation in etiology of travelers' diarrhea. Finnish-Moroccan Study Group.

The etiology of travelers' diarrhea was studied in 579 adult Finnish tourists participating in two packaged tours to Morocco in the winter (n = 233) and fall (n = 346) of 1989. A research team accompanied the travelers, and a laboratory for enteric pathogens was established in Agadir. At least one pathogen was found in 62% of the 60 diarrhea cases in winter and in 58% of the 111 diarrhea cases in fall. Multiple pathogens were found less often in winter (8%) than in fall (21%, P less than .05). Campylobacter strains were the leading cause of travelers' diarrhea in winter, found alone or with other pathogens in 28% of the cases (but in only 7% in fall), whereas enterotoxigenic Escherichia coli (ETEC) was the most common pathogen in fall, present in 32% of the cases (8% in winter). Both differences are highly significant (P less than .001). Salmonella enterica was almost as common as ETEC in fall (25% of diarrhea cases) but rare in winter (10%, P less than .05). Thus, the etiology of travelers' diarrhea varied according to the season in the same tourist destination. This finding has relevance to both antimicrobial treatment and prophylaxis.

Adolescent

Epidemiology of invasive Haemophilus influenzae type b disease.

Invasive disease caused by Haemophilus influenzae type b (Hib) is typically a disease of young children, starting when the protection afforded by maternal antibodies is exhausted and ending when the child's own antibody production to the Hib capsular polysaccharide begins efficiently. There are, however, large variations between population groups in the incidence of the disease and the age at which it appears. Potential factors behind this variation include virulence genes of the bacteria and genetic susceptibility genes of the host. Although such genes and their effects can be identified, their impact on the disease's incidence is only minor. Potentially much more important appear to be socioeconomic factors that to a large extent determine the exposure of the child to Hib and to other infectious agents that may enhance both colonization and invasive infection by Hib.

Age Factors

C-reactive protein in measles.

Seventy-two children with early measles (1st-3rd day of rash), presenting at two centres in Santiago, Chile, were classified as having mild ('ordinary measles', n = 50), or moderate to severe measles ('primarily severe measles', n = 22). The level of serum C-reactive protein (CRP) was determined by nephelometry from a finger prick sample. The mean CRP value in ordinary measles, 19 mg/l, was significantly lower (P less than 0.001) than in primarily severe measles where the mean CRP was 65 mg/l. During late measles (5th-8th day of rash), the mean CRP was 19 mg/l if the child recovered uneventfully (n = 35), whereas the mean level of 123 mg/l (P less than 0.001) was encountered when the child suffered from complicating pneumonia (n = 22). We conclude that the simple quantitative CRP determination is a useful alarm signal during the course of measles: elevated levels point to severity or complications in recovery.

Amoxicillin

Thrombocytosis and thrombocytopenia in childhood bacterial meningitis.

To assess factors affecting the development of reactive thrombocytosis during bacterial meningitis, thrombocyte counts of 311 children with cerebrospinal fluid culture-positive bacterial meningitis were followed during hospitalization. Thrombocytosis (platelet counts greater than 500 x 10(9)/liter) was seen in 49% of the patients after the first week of treatment. Thrombocyte counts were higher in infants and in patients with long duration of illness before admission. Subdural effusion and cephalosporin therapy were associated with more pronounced thrombocytosis We found no relation between thrombocytosis and neurologic complications, but the patients who died developed thrombocytopenia instead of thrombocytosis. The difference between the thrombocyte curves of the surviving and dying patients might be utilized in predicting the final outcome in the severest cases of bacterial meningitis. We speculate that inflammatory cytokines, especially interleukin 1-beta, induce reactive thrombocytosis in bacterial meningitis.

Adolescent

Pharmacokinetics of single-dose oral ciprofloxacin in infants and small children.

The pharmacokinetics of orally administered ciprofloxacin (CIP) was studied in seven infants aged 5 to 14 weeks and nine children aged 1 to 5 years, most of whom were Salmonella carriers. In each case, 15 mg of CIP per kg of body weight was given with water on an empty stomach, and timed serum samples were taken during the following 12 h. The elimination half-life of CIP was significantly (P less than 0.001) longer in the infants (2.73 +/- 0.28 h; mean +/- standard deviation) than it was in the children (1.28 +/- 0.52 h). The area under the serum CIP concentration-time curve (AUC) from time zero to infinity was 16.1 +/- 7.4 mg.h.liter-1 among the infants and 5.3 +/- 3.3 mg.h.liter-1 in the children (P less than 0.01). No significant differences in the maximum concentration in serum, time to maximum concentration in serum, or absorption half-life were observed between the two groups. In contrast, the mean residence time was twofold longer in the infants (4.6 h) than it was in the children (2.4 h; P less than 0.001). The findings suggest that elimination of CIP is particularly rapid in children who just have passed infancy; they may require doses at shorter time intervals than those required by infants or older children or adults. In general, an oral dose of 10 to 15 mg of CIP per kg three times daily seems appropriate for children aged 1 to 5 years.

Administration, Oral

Precise quantification of fever in childhood bacterial meningitis.

Precise quantity of fever was determined in 191 cases of childhood bacterial meningitis by calculating the areas between the line indicating 37.8 degrees C or 39.5 degrees C temperature and the line connecting all individual temperature values. Temperature measurements were performed rectally one to four times a day throughout the hospitalization. The obtained areas under the curves (AUC), expressed as degree-hours, proved to be a sensitive index for delineating each individual fever pattern and reflected the magnitude of fever more precisely than the traditional fever curves. Children under five had significantly (p less than 0.05) greater AUC than those at five to 15 years; similarly, patients with Haemophilus influenzae meningitis showed greater AUC (i.e., had more fever) than those with meningococcal disease (p less than 0.05). The overall rates of secondary (14%), persistent (16%), and prolonged fever (8%) were virtually identical to previous reports; no drug fever was reported in this study. In cases with prolonged fever, a significantly higher rate (40%) of neurological complications was found compared to those who became afebrile earlier. This method is potentially utilizable in other diseases and conditions where precise measurement of fever is of clinical or scientific relevance.

Adolescent

Serology versus clinical signs or symptoms and main laboratory findings in the diagnosis of exanthema subitum (roseola infantum).

Twenty-five patients with clinical exanthema subitum (roseola infantum) were enrolled into a study, where acute-phase and convalescent sera were examined for antibodies to human herpesvirus 6 (HHV-6), several other viruses, and other microbes. In addition, an acute-phase fecal specimen was examined for viruses by electron microscopy. Confirmative or suggestive serologic evidence for recent HHV-6 infection was obtained in 23 (92%) cases. Conversion to HHV-6 was found in 19 (76%), a diagnostic (greater than or equal to 4-fold) titer rise in 2, a twofold titer rise in 1, and a stable relatively high titer in 1 of the patients; only 2 (8%) individuals remained negative. The other microbial assays produced only two slight mycoplasma antibody rises and one rotavirus identification in the fecal specimen. It is concluded that if the clinical diagnosis of exanthema subitum is deemed doubtful, HHV-6 infection is verifiable in about 75% of the cases by serology.

Antibodies, Viral

Prevention of travellers' diarrhoea by oral B-subunit/whole-cell cholera vaccine.

B-subunit/whole-cell cholera vaccine (BS-WC) has been shown to give Bangladeshi mothers and children only 3 months' protection against severe diarrhoea due to enterotoxigenic Escherichia coli (ETEC). Since a long-lasting effect is not necessary for protection against travellers' diarrhoea, a prospective double-blind study was conducted among tourists who went to Morocco from Finland. 307 tourists received two oral doses of BS-WC, whereas 308 controls received a placebo before departure. A research team went out with tourists and a laboratory for enteric pathogens was set up on location. A faecal specimen was taken from 100 randomly selected subjects before departure, from all travellers with diarrhoea, and routinely after return. Enteropathogenic bacteria were not isolated from any of the pre-departure specimens but were present during or after the holiday in 47% of tourists with travellers' diarrhoea, and in 14% of those without diarrhoea. BS-WC induced a 52% protection (p = 0.013) against diarrhoea caused by ETEC. The protection was better for mixed infections (65%, p = 0.016). The protective efficacy against a combination of ETEC and any other pathogen was 71% (p = 0.02), and that against ETEC plus Salmonella enterica even better at 82% (p = 0.01). Partial protection against travellers' diarrhoea is thus obtainable by active immunisation with BS-WC.

Administration, Oral

Severity of childhood bacterial meningitis and duration of illness before diagnosis.

Rapid diagnosis of childhood bacterial meningitis (BM) is generally believed to be essential to avoid poor outcome. To see whether duration of illness before admission to hospital was related to the severity of illness, data from children with BM diagnosed in 18 paediatric hospitals in Finland from 1984 to 1989 were collected prospectively. We divided 286 cases with culture-positive cerebrospinal fluid (CSF) into three groups: BM with a history of up to 24 h (short-history group, n = 141), of more than 24 h and up to 48 h (intermediate-history group, n = 75), and of more than 48 h (long-history group, n = 70). The longer the history, the better the clinical condition of the child. If symptoms or signs of BM lasted 48 h or less, the child did significantly worse, as judged by seven variables, than if the history was longer than 48 h (level of consciousness, p less than 0.001; seizures, p less than 0.01; CSF protein concentration, p less than 0.001; positive CSF gram-stain, p less than 0.01; positive blood culture, p less than 0.05 in Haemophilus influenzae meningitis; serum C-reactive protein, p less than 0.01 between intermediate-history and long-history groups; and urine sodium concentration, p less than 0.001). The differences were not affected by causative organism, sex, age, or preadmission oral antimicrobial agents. The findings show that if BM follows an insidious pattern of disease, diagnostic delay may be unavoidable, which may have medicolegal implications.

Adolescent

Serum C-reactive protein in childhood meningitis in countries with limited laboratory resources: a Chilean experience.

Quantitative C-reactive protein (CRP) was determined sequentially by nephelometry and photometry from a finger prick serum sample in 67 children with bacterial meningitis (BM) and 16 children with aseptic meningitis (AM). The initial mean CRP value of 180 mg/liter in children with BM differed significantly from the 12 mg/liter found in those with AM (P less than 0.001). In BM a slow descent instead of rapid normalization or a secondary increase in sequential CRP values were early indicators of complications during recovery, such as resistance to the antibiotic. A significant difference in the mean CRP values between uneventful and complicated courses of BM was observed from the fourth day on (P less than 0.001). The measurements obtained with nephelometry correlated reliably with the more widely available photometry (r = 0.99). Easily performed rapid CRP determinations can considerably improve the quality of care in meningitis patients, especially in those situations where facilities for performing bacterial cultures or antibiotic susceptibility testing are not available.

C-Reactive Protein