Mika Paldanius

Size at birth, weight gain over the life course, and low-grade inflammation in young adulthood: northern Finland 1966 Birth Cohort study.

AIMS Low-grade inflammation might mediate associations between size at birth, early life growth, excessive weight gain, and subsequent risk of cardiovascular disease in adult life. Our aim was to investigate relationships between fetal growth, weight over the life course, and low-grade inflammation measured by serum high sensitivity C-reactive protein (CRP) levels at 31 years. METHODS AND RESULTS General population-based northern Finland 1966 Birth Cohort study of 5840 participants attending a clinical examination at 31 years, including measurement of CRP. Weight and height were assessed at birth, 12 months, and 14 and 31 years of age. CRP levels at 31 years were 16% [95% confidence interval (CI) 8, 23] higher per 1 kg lower birth weight, 21% (95% CI 2, 37) higher per 10 cm lower birth length, and 24% (95% CI 10, 36) higher per 1 kg/m3 lower ponderal index, after adjustment for potential confounders. Participants with highest tertile body mass index (BMI) at 31 years and lowest tertile birth weight had the highest average CRP levels. Per unit increase in BMI from 14 to 31 years was associated with 16% (95% CI 14, 17) higher CRP levels; the association was larger for those in the top BMI tertile at age 14 years. CONCLUSION Systemic low-grade inflammation may lie on the causal pathway that relates impaired fetal growth and weight gain from childhood to adulthood to adverse adult cardiovascular health. Lifestyle changes from early life might be an important step in reducing cardiovascular risk in adults.

The role of respiratory viral infections among children hospitalized for community-acquired pneumonia in a developing country.

We report an investigation for 16 bacteria and viruses among 184 children hospitalized with pneumonia in Salvador, Brazil. Etiology was established in 144 (78%) cases. Viral, bacterial, and mixed infections were found in 110 (60%), 77 (42%), and 52 (28%) patients, respectively. Rhinovirus (21%) and Streptococcus pneumoniae (21%) were the most common pathogens. Our results demonstrate the importance of viral and pneumococcal infections among those patients.

Aetiology of community-acquired pneumonia: Serological results of a paediatric survey

Serological methods are routinely used in the diagnosis of viral and atypical bacterial respiratory infections. Recently, they have also been applied to typical bacteria, such as Streptococcus pneumoniae. The aim of this study was to determine the aetiology of paediatric community-acquired pneumonia (CAP) in both ambulatory and hospitalized patients, by using antibody assays. During a 15-month prospective surveillance, paired sera were studied for antibodies to 14 microbes in 101 children with symptoms of acute infection and infiltrates compatible with pneumonia on chest radiographs. A potential causative agent was detected in 66 (65%) patients. Evidence of bacterial, viral and mixed viral-bacterial infection was demonstrated in 44%, 42% and 20% of the CAP cases, respectively. The most commonly found agents included Mycoplasma pneumoniae (27%), Pneumococcus (18%) and respiratory syncytial virus (17%). Human metapneumovirus (hMPV) was detected in 5 (5%) children. Pneumococcal infections were evenly distributed among the age groups studied. Our results confirm the role of S. pneumoniae in paediatric CAP at all ages, those of M. pneumoniae at >2 y of age and emphasize the emerging role of hMPV. The high proportion of mixed viral-bacterial infections highlights the need to treat all children with CAP with antibiotics.

Association between Chlamydia trachomatis antibodies and subfertility in the Northern Finland Birth Cohort 1966 (NFBC 1966), at the age of 31 years.

The objective of this study was to assess the serological association between previous Chlamydia trachomatis infection and subfertility in a general population sample. A nested case (n = 493)-control (n = 986) study in a population-based birth cohort consisting of 12,058 live births from the year 1966 was conducted. The analysis was restricted to those 6007 cohort members who replied to a postal inquiry and participated in a health examination including blood samples at the age of 31 years. The presence of C. trachomatis-specific serum IgG antibodies was screened by a synthetic peptide-based enzyme-linked immunosorbent assay. All the positive sera were further tested by the microimmunofluorescence method using immunotype pools and individual immunotypes of C. trachomatis as antigens. An association was found between the detection of immunotype-specific C. trachomatis antibodies and subfertility both in men and women. The results of the present study confirm the serological association between past C. trachomatis infections and subfertility in male or female partners of the couple in the population-based sample.

Low-grade, systemic inflammation in adolescents: Association with early-life factors, gender, and lifestyle

Low-grade, systemic inflammation is related to increased risk of cardiovascular disease in adults. The proinflammatory state tracks from adolescence to adulthood. Identifying correlates of inflammation in adolescents could provide opportunities to prevent cardiovascular disease in adulthood. However, population-based data on correlates of inflammation in adolescence are limited. Therefore, the authors studied the associations of early-life factors, gender, and lifestyle with inflammation (measured by high-sensitivity C-reactive protein and leukocyte count) at age 16 years (2001-2002) in the prospective, population-based Northern Finland Birth Cohort 1986 Study (n = 5,240). In females, being born small for gestational age and current use of oral contraceptives were associated with the proinflammatory state. The association of birth size with inflammation was not observed in males. In logistic regression analyses, oral contraceptive use (odds ratio (OR) = 2.83), abdominal obesity (OR = 5.17), and smoking (OR = 2.72) were associated with elevation of both inflammation markers in females; abdominal obesity (OR = 5.72) and smoking (OR = 2.02) were associated in males. Thus, females appear more susceptible to the adverse effects of being born small for gestational age than males. Given the widespread use of oral contraceptives and the potential pathophysiologic consequences of the proinflammatory state, the association of oral contraceptive use with inflammation in adolescence may have public health implications.

Procalcitonin is useful in identifying bacteraemia among children with pneumonia.

Abstract Empirical antibiotic use is prescribed in managing children with pneumonia worldwide. We assessed the usefulness of procalcitonin (PCT) and interferon-alpha (IFN-α) in differentiating viral from bacterial pneumonia. Among 159 hospitalized children, pneumonia was diagnosed based on clinical complaints plus pulmonary infiltrate. Aetiology was investigated for 9 viruses and 4 atypical and 3 typical bacteria. PCT and IFN-α were measured in the serum sample collected on admission. Eight patients had bacteraemic infections, 38 had non-bacteraemic typical infections, and 19 patients had atypical bacterial infections. Viral and unknown aetiology was established in 57 (36%) and 34 (21%) cases, respectively. Three patients with bacterial infection without collected blood culture were excluded. IFN-α (IU/ml) was detectable in 20 (13%) cases. The difference among median PCT values of the bacteraemic (4.22; 1.56–7.56), non-bacteraemic typical bacterial (1.47; 0.24–4.07), atypical bacterial (0.18; 0.06–1.03) and only viral (0.65; 0.11–2.22) subgroups was significant (p = 0.02). PCT was ≥2 ng/ml in 52 (33%) cases. The presence of IFN-α was associated with PCT <2 ng/ml (90% vs. 64%, p = 0.02). The negative predictive value (95% confidence interval) of PCT ≥2 ng/ml was 95% (89–100%), 89% (78–100%), 93% (85–100%) for differentiation of bacteraemic from viral, atypical bacterial and non-bacteraemic typical bacterial infection, respectively, and 58% (49–68%) for differentiation between bacterial and viral infection. PCT may be useful in identifying bacteraemia among children hospitalized with community-acquired pneumonia. IFN-α was uncommonly detected.

Seasonal patterns of viral and bacterial infections among children hospitalized with community-acquired pneumonia in a tropical region

Abstract Community-acquired pneumonia (CAP) is a common cause of morbidity among children. Evidence on seasonality, especially on the frequency of viral and bacterial causative agents is scarce; such information may be useful in an era of changing climate conditions worldwide. To analyze the frequency of distinct infections, meteorological indicators and seasons in children hospitalized for CAP in Salvador, Brazil, nasopharyngeal aspirate and blood were collected from 184 patients aged <5 y over a 21-month period. Fourteen microbes were investigated and 144 (78%) cases had the aetiology established. Significant differences were found in air temperature between spring and summer (p = 0.02) or winter (p < 0.001), summer and fall (p = 0.007) or winter (p < 0.001), fall and winter (p = 0.002), and on precipitation between spring and fall (p = 0.01). Correlations were found between: overall viral infections and relative humidity (p = 0.006; r = 0.6) or precipitation (p = 0.03; r = 0.5), parainfluenza and precipitation (p = 0.02; r = −0.5), respiratory syncytial virus (RSV) and air temperature (p = 0.048; r = −0.4) or precipitation (p = 0.045; r = 0.4), adenovirus and precipitation (p = 0.02; r = 0.5), pneumococcus and air temperature (p = 0.04; r = −0.4), and Chlamydia trachomatis and relative humidity (p = 0.02; r = −0.5). The frequency of parainfluenza infection was highest during spring (32.1%; p = 0.005) and that of RSV infection was highest in the fall (36.4%; p < 0.001). Correlations at regular strength were found between several microbes and meteorological indicators. Parainfluenza and RSV presented marked seasonal patterns.

Serum C-reactive protein and Chlamydia trachomatis antibodies in preterm delivery

OBJECTIVE: To assess the association between Chlamydia trachomatis antibodies, antibodies to C trachomatis heat shock proteins 60 and 10, and C-reactive protein (CRP) levels in maternal serum measured by highly sensitive CRP assay during the first trimester and spontaneous preterm delivery before 37 weeks of gestation. Methods: This was a nested case–control study of 104 spontaneous preterm singleton deliveries (cases) and 402 term singleton deliveries, as controls, of mothers belonging to the population-based Northern Finland 1966 Birth Cohort. Data on 2,309 first deliveries were available from the Finnish Medical Birth Register. Serum C trachomatis and C pneumoniae antibodies were measured by the microimmunofluorescence test and chlamydial heat shock proteins 60 and 10 antibodies by enzyme immunoassay using recombinant proteins as antigens, and highly sensitive CRP levels were quantified with highly sensitive immunoenzymometric assay. Results: Highly sensitive CRP levels were higher and C trachomatis immunoglobulin G levels (pools and individual serotypes) were more often present (thought not nominally significantly in all cases) in the women with preterm compared with term deliveries. Elevated immunoglobulin G levels of C trachomatis antibodies or elevated highly sensitive CRP levels alone, however, did not increase the estimated risk for preterm delivery, but when they were present simultaneously, the estimated risk for preterm delivery was 4-fold (odds ratio 4.3, 95% confidence interval 2.0–9.3). Among the women delivered at or before 34 weeks of gestation, the estimated risk was even more evident (odds ratio 5.6, 95% confidence interval 2.1–14.5). The preterm delivery rate was 26.5% for those with C trachomatis antibodies and 18.8% for those without C trachomatis antibodies. Conclusion: The results of the present study suggest that chlamydial infection in the first trimester is associated with preterm delivery. Level of Evidence: II-2

Simkania negevensis in community-acquired pneumonia in Italian children

Simkania negevensis, a recently found Chlamydia-like organism, has been associated with respiratory infections in children and adults with pneumonia, but S. negevensis findings have been common also without any infection. The aims of the present paper were to evaluate S. negevensis in the aetiology of paediatric community-acquired pneumonia (CAP), its seroprevalence in north Italian children, and whether there is cross-reactivity between S. negevensis and Chlamydia pneumoniae serology. Antibodies to S. negevensis were measured by microimmunofluorescence (MIF) in 101 frozen paired sera obtained from children with CAP. Serological evidence (>/=4-fold increase or decrease in IgM or IgG) of acute S. negevensis infection was achieved in 5 (5%) cases. Two were mixed infections with Mycoplasma pneumoniae and 1 with respiratory syncytial virus. In total, 20–30% of the children had measurable antibodies to S. negevensis, with no association with age. No cross-reactivity was observed between antibodies to S. negevensis and C. pneumoniae. S. negevensis appears to be a real, though rare, cause of CAP in children.

Simkania negevensis may be a true cause of community acquired pneumonia in children

Simkania negevensis, a recently found Chlamydia-like organism, has been associated with bronchiolitis and pneumonia in children. S. negevensis findings have been common also in healthy, non-symptomatic subjects. Antibodies to S. negevensis were measured by microimmunofluorescence in 174 frozen paired sera obtained from children with community acquired pneumonia in a population-based study. There was evidence of S. negevensis infection in 18 (10%) cases. All diagnoses were based on the presence of specific IgM antibodies. The numbers of S. negevensis cases increased from 2 (4%) at <24 months to 7 (15%) at ≥10 y of age. 12 (67%) were mixed infections with viruses or other bacteria. 16 children (9%) had measurable IgG antibodies to S. negevensis, but significant rises were not found in any cases. Thus, S. negevensis may be a real, though rare, cause of CAP in children, occurring often in mixed infections with viruses and other bacteria.