The feasibility of existing JADAS10 cut-off values in clinical practice: a study of data from The Finnish Rheumatology Quality Register

BACKGROUND

The ten-joint juvenile arthritis disease activity score (JADAS10) is designed to measure the level of disease activity in non-systemic juvenile idiopathic arthritis by providing a single numeric score. The clinical JADAS10 (cJADAS10) is a modification of the JADAS10 that excludes erythrocyte sedimentation rate (ESR). Three different sets of JADAS10/cJADAS10 cut-offs for disease activity states have been published, i.e., the Backström, Consolaro, and Trincianti cut-offs. The objective of this study was to investigate the performance of existing JADAS10 cut-offs in real-life settings using patient data from The Finnish Rheumatology Quality Register (FinRheuma).

METHODS

Data were collected from the FinRheuma register. The proportion of patients with an active joint count (AJC) above zero when classified as being in clinically inactive disease (CID) or low disease activity (LDA) groups according to existing JADAS10/cJADAS10 cut-off levels were analyzed.

RESULTS

A significantly larger proportion of the patients classified as being in CID had an AJC > 0 when using the JADAS10/cJADAS10 cut-offs by Trincianti et al. compared to those for the other cut-offs. In the LDA group, a significantly larger proportion of the polyarticular patients (35%/29%) had an AJC of two when Trincianti JADAS10/cJADAS10 cut-offs were used compared with when Backström (11%/10%) and Consolaro (7%/3%) JADAS10/cJADAS10 cut-offs were used.

CONCLUSIONS

We found the cut-offs proposed by Consolaro et al. to be the most feasible, since these cut-off levels for CID do not result in the misclassification of active disease as remission, and the proportion of patients with AJC > 1 in the LDA group is lowest using these cut-offs.

Etanercept for patients with juvenile idiopathic arthritis: drug levels and influence of concomitant methotrexate: observational study

BACKGROUND

Etanercept (ETN) is widely used tumour necrosis factor (TNF) blocker in the treatment of juvenile idiopathic arthritis (JIA) when traditional synthetic disease modifying antirheumatic drug (sDMARD) therapy is not sufficient. There is limited information about the effects of methotrexate (MTX) on serum ETN concentration in children with JIA. We aimed to investigate whether ETN dose and concomitant MTX would effect ETN serum trough levels in JIA patients, and whether concomitant MTX have an influence on the clinical response in patients with JIA receiving ETN.

METHODS

In this study, we collected the medical record data of 180 JIA patients from eight Finnish pediatric rheumatological centres. All these patients were treated with ETN monotherapy or combination therapy with DMARD. To evaluate the ETN concentrations, blood samples of the patients were collected between injections right before the subsequent drug. Free ETN level was measured from serum.

RESULTS

Ninety-seven (54%) of the patients used concomitant MTX, and 83 (46%) received either ETN monotherapy or used sDMARDs other than MTX. A significant correlation was noted between ETN dose and drug level [r = 0.45 (95% CI: 0.33-0.56)]. The ETN dose and serum drug level were correlated (p = 0.030) in both subgroups - in MTX group [r = 0.35 (95% CI: 0.14-0.52)] and in non-MTX group [r = 0.54 (95% CI: 0.39-0.67)].

CONCLUSION

In the present study, we found that concomitant MTX had no effect on serum ETN concentration or on clinical response. In addition, a significant correlation was detected between ETN dose and ETN concentration.

Pain-coping scale for children and their parents: a cross-sectional study in children with musculoskeletal pain

BACKGROUND

In a chronic pain-causing disease such as juvenile idiopathic arthritis, the quality of coping with pain is crucial. Parents have a substantial influence on their children's pain-coping strategies. This study aimed to develop scales for assessing parents' strategies for coping with their children's pain and a shorter improved scale for children usable in clinical practice.

METHODS

The number of items in the Finnish version of the pain-coping questionnaire for children was reduced from 39 to 20. A corresponding reduced scale was created for parental use. We recruited consecutive patients from nine hospitals evenly distributed throughout Finland, aged 8-16 years who visited a paediatric rheumatology outpatient clinic and reported musculoskeletal pain during the past week. The patients and parents rated the child's pain on a visual analogue scale from 0 to 100 and completed pain-coping questionnaires and depression inventories. The selection process of pain questionnaire items was performed using factor analyses.

RESULTS

The average (standard deviation) age of the 130 patients was 13.0 (2.3) years; 91 (70%) were girls. Four factors were retained in the new, improved Pain-Coping Scales for children and parents. Both scales had 15 items with 2-5 items/factor. The goodness-of-fit statistics and Cronbach's alpha reliability coefficients were satisfactory to good in both scaled. The criterion validity was acceptable as the demographic, disease related, and the depression and stress questionnaires correlated with the subscales.

CONCLUSIONS

We created a shorter, feasible pain-coping scale for children and a novel scale for caregivers. In clinical work, the pain coping scales may serve as a visualisation of different types of coping strategies for paediatric patients with pain and their parents and facilitate the identification of families in need of psychological support.

Economic evaluation of infliximab, synthetic triple therapy and methotrexate in the treatment of newly diagnosed juvenile idiopathic arthritis

BACKGROUND

Evaluation of costs and short-term cost-effectiveness of infliximab plus methotrexate (IFX + MTX); triple therapy of hydroxychloquine, sulphasalazine, and methotrexate (TRIPLE); or methotrexate monotherapy (MTX) in patients with new-onset polyarticular juvenile idiopathic arthritis (JIA).

METHODS

In a prospective multicenter study (ACUTE-JIA), costs and health outcomes of 60 randomized patients with new-onset disease-modifying anti-rheumatic drug (DMARD)-naïve polyarticular JIA were analyzed during the first year. A mapping algorithm was used to obtain utility values from Child Health Assessment Questionnaire (CHAQ). Wallace criteriae were used to assess clinically inactive disease (CID). Linear regression with non-parametric bootstrapping was used to adjust imbalances at baseline.

RESULTS

Using prices for IFX biosimilar, adjusted annual mean (SD) costs of treatment (€) were 21,164 (4158), 12,136 (5286), and 18,300 (8635) on IFX + MTX, TRIPLE, and MTX, respectively. Incremental cost-effectiveness ratio (ICER) for IFX + MTX as compared with TRIPLE or MTX were 3442 € or 678 € per additional month spent in CID. Mean (SD) quality-adjusted life years (QALYs) for IFX + MTX, TRIPLE and MTX were 0.755 (0.065), 0.725 (0.062), and 0.686 (0.124). ICER for IFX + MTX vs TRIPLE was 294,433 €, and for IFX + MTX vs MTX 31,435 € per QALY gained.

CONCLUSIONS

In short-term, biosimilar IFX + MTX can be considered cost-effective when compared with MTX alone. TRIPLE was cost-effective when compared with MTX and showed cost advantage when compared with IFX + MTX. Cost per time spent in CID showed similar results than ICER evaluations.

TRIAL REGISTRATION

This trial was primarily registered with the Ethical Board of Helsinki District University Hospital ( https://www.hus.fi ), clinical trial number 211864, and later with ClinicalTrials.gov, number NCT01015547.

Short interruptions of TNF-inhibitor treatment can be associated with treatment failure in patients with immune-mediated diseases

INTRODUCTION

The prevalence of immune-mediated diseases has increased in the past decades and despite the use of biological treatments all patients do not achieve remission. The aim of this study was to characterise the reasons for short interruptions during treatment with two commonly used TNF-inhibitors infliximab and adalimumab and to analyse the possible effects of the interruptions on immunisation and switching the treatment.

MATERIAL AND METHODS

This case-control study was based on retrospective analyses of patient records and a questionnaire survey to clinicians. A total of 370 patients (194 immunised cases and 172 non-immunised controls, 4 excluded) were enrolled from eight hospitals around Finland. Eleven different diagnoses were represented, and the largest patient groups were those with inflammatory bowel or rheumatic diseases.

RESULTS

Treatment interruptions were associated with immunisation in patients using infliximab (p < .001) or adalimumab (p < .000001). Patients with treatment interruptions were more likely to have been treated with more than one biological agent compared to those without treatment interruptions. This was particularly prominent among patients with a rheumatic disease (p < .00001). The most frequent reason for a treatment interruption among the cases was an infection, whereas among the control patients it was remission. The median length of one interruption was one month (interquartile range 1-3 months).

CONCLUSION

Our results suggest that the interruptions of the treatment with TNF-inhibitors expose patients to immunisation and increase the need for drug switching. These findings stress the importance of careful judgement of the need for a short interruption in the biological treatment in clinical work, especially during non-severe infections.

POS0335 IMPROVED PAIN COPING SCALE FOR CHILDREN AND THEIR CAREGIVERS

Background

Pain can be a problem in a subgroup of juvenile idiopathic arthritis (JIA) patients even though in clinical remission. This can at least partly be due to their pain coping strategy of catastrophizing [1]. In a chronic disease such as JIA, the quality of coping with pain is crucial. The importance of coping with pain is well recognized in children [2]. The understanding of the parental role in supporting the child in pain is growing [3]; yet measuring the precise mechanism of parental pain coping is less studied. Thus, it seems important to measure also parental coping quality.

Objectives

The aim of this study was to develop a pain coping scale (PCSpar) for assessing the parents’ coping strategies to their child´s pain and a shorter improved PCSped for children feasible for use in clinical practice.

Methods

The original pain coping questionnaire (PCQ) [4] has been validated in Finnish [5] resulting in a 38-item, eight-factor structured PCQ. The items in the new version of PCQ were reduced into twenty by an interdisciplinary team (mPCQped). A corresponding scale was created for parental use (mPCQpar). Consecutive patients aged 8-16 years, visiting pediatric rheumatology outpatient clinic, reporting musculoskeletal pain during the last week before visit or longer, were recruited to participate in this study. Both the patient and the caregiver rated the child’s pain VAS from 0 to 100, completed the mPCQped /the mPCQpar and Children´s Depression Inventory (CDI) [6]/the Beck´s depression Inventory (BDI) [7] as appropriate. The selection process of pain questionnaire items was performed with factor analyses. The construct validity, the associations of the mPCQ factors, CDI, BDI and pain VAS, were tested by Spearman´s correlation coefficient.

Results

The study was conducted in all five tertiary and four secondary hospitals evenly distributed throughout Finland. Of the 153 families invited to the study, 130 attended. The average (SD) age of the attending patients was 13.0 (2.3) years. Of the patients, 91 (70%) were girls. Several steps in the exploratory factor analyses preceded the final factor analyses mPCQped and mPCQpar results. The four factors retained in the new improved Pain Coping Scale for children (iPCSped) were named positive cognitive distraction, catastrophizing (CATped), seeking social support (SSSped) and behavioral distraction. The factors in the improved Pain Coping Scale for caregivers (iPCSpar) were positive self-statement, catastrophizing (CATpar), seeking social support and distraction. In both iPCSped and iPCSpar there are a total of 15 items, 2-5 items/factor. The factor´s Cronbach´s alpha reliability coefficients were satisfactory, and the goodness-of-fit statistics were good. The CATpar correlated to BDI Rs= 0.33, p<0.05 and parent’s assessment of the child’s pain Rs= 0.23, p<0.05 in caregivers. The CATped correlated to CDI Rs= 0.49, p<0.05 and SSSped Rs= 0.26, p=0.05 but not to patient pain VAS Rs= 0.08, p>0.05.

Conclusion

In this study, we created a shorter pain coping scale for children (iPCSped) and a novel scale for caregivers (iPCSpar). Both showed good validity and reliability.

References

[1]Lomholt JJ et al. Pediatric Rheumatology 2013;11:21-28.

[2]Gaultney, AC et al. Children 2017;4:11.

[3]Caes L et al. Front. Psychol 12:680546. doi: 10.3389/fpsyg.2021.680546

[4]Reid GJ et al. Pain 1998;76:83-96.

[5]Marttinen MK et al. Eur J Pain 2018;22:1016-1025.

[6]Kovacs M et al. Psychopharmacil Bull 1985;21:995-8.

[7]Beck AT et al. Arch Gen Psychiatry 1961;4:561–71.

Disclosure of Interests

None declared

SAT0488 ETANERCEPT CONCENTRATION IN PATIENTS WITH JUVENILE IDIOPATHIC ARTHRITIS

Background:

Etanercept (ETN) is the most used TNF blocker in children with JIA. There is still limited real-life data of etanercept concentrations in children, especially in association with dosing.

Objectives:

The aim of the study was to investigate association between ETN dosing and serum trough concentration in children with non-systemic JIA.

Methods:

We conducted a multicenter retrospective study of 180 Finnish JIA patients (Table 1) receiving ETN either as monotherapy or in combination with one or more DMARDs (Table 2). Prior biologicals were used by 17 % of the patients. Patients were divided into two groups, ETN started before or after one year of diagnosis (Figure 1). ETN concentration samples (collected 2014-2017) were analyzed using validated enzyme-linked immunosorbent assay (ELISA) in Sanquin Diagnostics, Amsterdam, the Netherlands.

Results:

Demographics at etanercept start and diagnoses are shown in Table 1. Duration of the treatment with ETN, ETN doses, concentrations and concomitant medications at the time of concentration measurement are shown in Table 2.

Association between ETN dose and concentration is shown in Figure 1.

Those who started medication early (< 1 year from diagnosis) were younger than those who started later (Table 1) and association between ETN dose and concentration was more obvious (Figure 1).

Conclusion:

There was an association between etanercept dose used and serum trough concentration and it was more evident when medication was started early after diagnosis, when the patients were younger and BSA lower.

References:

[1]Kneepkens EL et al. Lower etanercept levels are associated with high disease activity in ankylosing spondylitis patients at 24 weeks of follow-up. Ann Rheum Dis 2015;74(10):1825-9.

[2]Bader-Meunier B et al. Etanercept concentration and immunogenicity do not influence the response to Etanercept in patients with juvenile idiopathic arthritis. Semin Arthritis Rheum 2019;48(6):1014-1018.

Disclosure of Interests:

None declared

Efficacy and safety of tocilizumab in a real-life observational cohort of patients with polyarticular juvenile idiopathic arthritis

Objectives

To evaluate the patterns of usage, efficacy and safety of tocilizumab in polyarticular JIA.

Methods

An observational study of 56 consecutive polyarticular JIA patients was conducted using patient charts and electronic JIA databases. Efficacy was assessed by tocilizumab survival, rates of low disease activity (LDA) and of inactive disease by 10-joint Juvenile Arthritis Disease Activity Score (JADAS-10), and of clinically inactive disease according to Wallace’s preliminary criteria. Efficacy and rate of adverse events (AEs) were evaluated during a 24-month period after tocilizumab commencement.

Results

Tocilizumab was started on average as third-line biological agent (median, range first- to fourth-line) at a median disease duration of 5.2 years (interquartile range 3.0–7.7). Survival rates were 82% at 12 months and 64% at 24 months. The reasons for discontinuation were inadequate treatment effect in 50%, AE plus inadequate treatment effect in 37.5% and AE alone in 12.5%. LDA (JADAS-10 ⩽3.9) was reached in 58% at 12 months and in 84% at 24 months, inactive disease (JADAS-10 ⩽0.7) in 19% and 44%, and clinically inactive disease in 28% and 46%, respectively. The rate of AEs was 200.9/100 patient years and of serious AEs 12.9/100 patient years.

Conclusion

Survival of tocilizumab was high and a large proportion of the treatment-resistant patients reached LDA at 12 months of treatment. The LDA rate continued to increase throughout 24 months. The rates of AEs and serious AEs were higher than in register studies but lower than in the originator study of tocilizumab.

A novel mutation in the matrix metallopeptidase 2 coding gene associated with intrafamilial variability of multicentric osteolysis, nodulosis, and arthropathy

Background

MONA, which stands for a spectrum of Multicentric Osteolysis, subcutaneous Nodulosis, and Athropathia, is an ultra rare autosomal recessive disorder caused by mutations in the matrix metallopeptidase 2 (MMP2) gene. To date only 44 individuals, carrying 22 different mutations have been reported. Here we report on two brothers with identical homozygous MMP2 gene mutations, but with clearly different phenotypes.

Methods

Genomic DNA was isolated from the affected brothers and the parents. An iliac crest bone biopsy was taken from the younger patient (index case). The level of matrix metallopeptidase 2 enzyme (MMP2) in serum and synovial fluid of the younger patient was analyzed using gelatin zymography.

Results

The DNA analysis revealed a homozygous c.1188C>A transversion on exon 8 of the gene. The affected brothers had the same homozygous variant and the parents were heterozygous to this variant. This variant has been reported as a compound heterozygous mutation on one individual resulting in scleroderma like skin thickening. Bone histomorphometry indicated increased trabecular bone remodeling and turnover. The zymography revealed that the level of MMP2 was completely nonmeasurable in the serum and only a minor gelatinolytic protein band of about similar molecular weight as MMP2 was found in the synovial fluid.

Conclusions

Both the age at the onset and the phenotypic severity of the syndrome in these two brothers were different despite identical genotypes. The younger patients had corneal opacities leading to deteriorating visual acuity. For the first time in this disease, opacities were successfully treated with corneal transplantations.

Cryopyrin-associated periodic syndrome in early childhood can be successfully treated with interleukin-1 blockades

Cryopyrin-associated periodic syndrome (CAPS) is caused by a mutation in the NLRP3 gene encoding cryopyrin production. Overproduction of interleukin-1 (IL-1) leads to symptoms that are associated with elevated inflammatory markers, including periodic fever and a rash. We provide a clinical overview of CAPS in children, including three Finnish case studies.

CONCLUSION

When CAPS has been diagnosed, an IL-1 blockade with biological should be introduced to lessen the symptoms and to prevent the progression of organ damage.

Body fat mass, lean body mass and associated biomarkers as determinants of bone mineral density in children 6-8years of age - The Physical Activity and Nutrition in Children (PANIC) study

Lean body mass (LM) has been positively associated with bone mineral density (BMD) in children and adolescents, but the relationship between body fat mass (FM) and BMD remains controversial. Several biomarkers secreted by adipose tissue, skeletal muscle, or bone may affect bone metabolism and BMD. We investigated the associations of LM, FM, and such biomarkers with BMD in children. We studied a population sample of 472 prepubertal Finnish children (227 girls, 245 boys) aged 6-8years. We assessed BMD, LM, and FM using whole-body dual-energy x-ray absorptiometry and analysed several biomarkers from fasting blood samples. We studied the associations of LM, FM, and the biomarkers with BMD of the whole body excluding the head using linear regression analysis. LM (standardized regression coefficient β=0.708, p<0.001), FM (β=0.358, p<0.001), and irisin (β=0.079, p=0.048) were positive correlates for BMD adjusted for age, sex, and height in all children. These associations remained statistically significant after further adjustment for LM or FM. The positive associations of dehydroepiandrosterone sulphate (DHEAS), insulin, homeostatic model assessment for insulin resistance (HOMA-IR), leptin, free leptin index, and high-sensitivity C-reactive protein and the negative association of leptin receptor with BMD were explained by FM. The positive associations of DHEAS and HOMA-IR with BMD were also explained by LM. Serum 25-hydroxyvitamin D was a positive correlate for BMD adjusted for age, sex, and height and after further adjustment for FM but not for LM. LM and FM were positive correlates for BMD also in girls and boys separately. In girls, insulin, HOMA-IR, leptin, and free leptin index were positively and leptin receptor was negatively associated with BMD adjusted for age, height, and LM. After adjustment for age, height, and FM, none of the biomarkers was associated with BMD. In boys, leptin and free leptin index were positively and leptin receptor was negatively associated with BMD adjusted for age, height, and LM. After adjustment for age, height and FM, 25(OH)D was positively and IGF-1 and leptin were negatively associated with BMD. FM strongly modified the association between leptin and BMD. LM but also FM were strong, independent positive correlates for BMD in all children, girls, and boys. Irisin was positively and independently associated with BMD in all children. The associations of other biomarkers with BMD were explained by LM or FM.

Interleukin 17A gene polymorphism rs2275913 is associated with osteitis after the Bacillus Calmette-Guérin vaccination

AIM

Interleukin-17 (IL-17) appears to promote the host's defence against mycobacterial infections. This study evaluated the association between IL17A gene polymorphism and the risk of Bacillus Calmette-Guérin (BCG) osteitis after newborn vaccination and between IL17A gene polymorphism and IL-17A concentrations in serum.

METHODS

IL17A rs2275913 gene polymorphisms and serum IL-17A concentrations were studied in 132 adults aged 21-49 years from across Finland, who had BCG osteitis in infancy after a newborn BCG vaccination. The subjects were recruited in 2007-2008, and their whole-blood samples were sent to the National Institute for Health and Welfare, Turku, Finland. Their genotypes and minor allele frequencies were compared with 405 population-based unvaccinated controls aged two to three months from a prospective birth cohort study.

RESULTS

The genotypes and allele frequencies of IL17A rs2275913 differed significantly between the former BCG osteitis patients and controls. The genotype was variant in 75.8% of cases and 64.0% of controls (p = 0.012), and the minor allele frequency was 50.0% in the cases and 41.6% of the controls (p = 0.009). Serum IL-17 concentrations did not differ significantly between the cases with wild or variant genotypes.

CONCLUSION

IL17A rs2275913 gene polymorphism was associated with a risk of BCG osteitis after vaccination.

Haplotype of the Interleukin 17A gene is associated with osteitis after Bacillus Calmette-Guerin vaccination

Bacillus Calmette-Guerin (BCG) osteitis was more common in Finland than elsewhere at the time when universal BCG vaccinations were given to Finnish newborns. There is evidence that IL-17 plays a role in the defense against tuberculosis. The aim of this study was to evaluate the associations of IL17A rs4711998, IL17A rs8193036 and IL17A rs2275913 single-nucleotide polymorphisms (SNPs) with the risk of BCG osteitis after newborn vaccination. IL17A rs4711998, rs8193036 and rs2275913 SNPs were determined in 131 adults had presented with BCG osteitis after newborn BCG vaccination. We analyzed, using the HaploView and PLINK programs, whether allele or haplotype frequencies of these SNPs differ between the former BCG osteitis patients and Finnish population controls. Of the three IL17A SNPs studied, rs4711998 associated nominally with BCG osteitis; minor allele frequency was 0.215 in 130 BCG osteitis cases and 0.298 in 99 controls (p = 0.034). Frequency of the second common haplotype (GTA) differed significantly between BCG osteitis cases and controls (0.296 vs. 0.184, p = 0.040 after multi-testing correction). The GTA haplotype of the IL17A SNPs rs4711998, rs8193036 and rs2275913 was associated with osteitis after BCG vaccination.

Cow's Milk Allergy in Infancy and Later Development of Juvenile Idiopathic Arthritis: A Register-Based Case-Control Study

We examined the association between cow's milk allergy (CMA) and juvenile idiopathic arthritis (JIA). The material for this case-control study was collected from national registers of all children born in Finland between 2000 and 2010 and diagnosed with JIA (n = 1,298) and age-, sex-, and place-matched controls (n = 5,179). We identified 235 children with CMA; 66 of these children also had JIA. A conditional logistic regression analysis was performed to evaluate the association between CMA and JIA and to test whether exposure to antibiotics would be a covariate for this association. In boys (but not in girls), a diagnosis of CMA and the use of hypoallergenic formula in infancy were associated with the later development of JIA (odds ratio = 2.4, 95% confidence interval: 1.6, 3.6). The association was most evident in boys who were diagnosed with JIA before age 3 years or diagnosed with CMA with predominantly gastrointestinal symptoms. There was no statistically significant additive interaction between CMA and antibiotic exposure in the later development of JIA. These associations may reflect impaired maturation of intestinal immunity and integrity in boys with a risk of JIA. Predisposing factors related to JIA pathogenesis seem to display a sex-linked disparity.

Interleukin-10 gene promoter region polymorphisms are not associated with BCG osteitis in vaccinated infants

SETTING

Complications arising from bacille Calmette-Guérin (BCG) vaccination were recorded in a national register in Finland until 1988. In the period 1960-1988, 222 patients suffered from BCG osteitis.

OBJECTIVE

To evaluate whether single nucleotide polymorphisms (SNPs) in the promoter region of the gene encoding interleukin 10 (IL-10) are associated with BCG osteitis after vaccination in neonates.

DESIGN

Blood samples of 132 former BCG osteitis patients now aged 21-49 years were analysed in a controlled study for IL10 rs1800896 (-1082G/A), rs1800871 (-819C/T), rs1800872 (-592C/A) and rs1800890 (-3575T/A) polymorphisms.

RESULTS

The frequencies of genotypes of IL10 rs1800896, rs1800871, rs1800872 and rs1800890, the frequencies of variant genotypes and the frequencies of major or minor alleles did not differ between patients and controls. Furthermore, the frequencies of the eight possible combinations of the three IL10 alleles located close to each other (IL10 rs1800896, IL10 rs1800871 and IL10 rs1800872) were surprisingly similar.

CONCLUSION

Our results suggest that polymorphisms of the IL-10 encoding gene do not play a central role in the development of complications due to BCG vaccination, although the IL10 gene, especially IL10 rs1800896 (-1082G/A) polymorphism, is known to be associated with tuberculosis risk in Europeans and North Americans.

[Chronic nonbacterial osteomyelitis]

Chronic nonbacterial osteomyelitis is an autoinflammatory disease occurring mainly in children and adolescents, typically involving recurrent or persistent osteitic foci. The symptom is bone pain, possibly accompanied by soft tissue tenderness. Some patients exhibit symptoms of systemic inflammation. The. precise etiology of the disease is not known, but an imbalance of inflammatory and anti-inflammatory cytokines is presumed to play a role in the development of the disease. While an anti-inflammatory analgesic is in most cases sufficient to calm down the osteitis, the use of corticosteroids, anti- TNF-a inhibitors or bisphosphonates is required in some cases.

Toll-like receptor 2 subfamily gene polymorphisms are associated with Bacillus Calmette-Guérin osteitis following newborn vaccination

AIM

Toll-like receptor (TLR) 1, 2, 6 and 10, the TLR2 subfamily, are known to be associated with immunity against tuberculosis. We evaluated whether polymorphisms in genes encoding TLR1, TLR2 and TLR6 were associated with osteitis in infants who received the Bacillus Calmette-Guérin (BCG) vaccination soon after birth.

METHODS

Blood samples from 132 adults aged 21-49 who had BCG osteitis in early childhood were analysed in a controlled study for TLR1 T1805G (rs5743618), TLR2 G2258A (rs5743708) and TLR6 C745T (rs5743810) gene single nucleotide polymorphisms.

RESULTS

The frequencies of the variant genotypes differed between the cases and controls: 11.4% versus 5.7% for TLR2 G2258A (p = 0.033) and 77.3% versus 61.6% for TLR6 C745T (p = 0.001). The TLR2 and TLR6 variant genotypes were associated with a higher risk of BCG osteitis, with adjusted odds ratios (aOR) of 2.154 (95%CI 1.026-4.521) and 1.907 (95%CI 1.183-3.075), respectively. The frequency of the TLR1 T1805G variant genotype was 19.7% in the cases and 33.6% in the controls (p = 0.003). The TLR1 variant genotype was associated with a lower risk of BCG osteitis (aOR 0.554, 95%CI 0.336-0.911).

CONCLUSION

Gene polymorphisms that regulate the function of the TLR2 subfamily play a role in the development of BCG osteitis in vaccinated infants.

Repeated exposure to antibiotics in infancy: a predisposing factor for juvenile idiopathic arthritis or a sign of this group's greater susceptibility to infections?

OBJECTIVE

Previous exposure to antibiotics has been associated with the pathogenesis of several autoimmune diseases. Our objective was to explore whether childhood exposure to antibiotics would be associated with the risk of developing juvenile idiopathic arthritis (JIA).

METHODS

The material was collected from national registers containing all children born in 2000-2010 in Finland and diagnosed with JIA by the end of December 2012 (n = 1298) and appropriate controls (n = 5179) matched for age, sex, and place of birth. All purchases of antibiotics were collected from birth until the index date (i.e., the date of special reimbursement for JIA medications). A conditional logistic regression was performed to evaluate the association between the exposure to antibiotics and the risk of JIA.

RESULTS

The risk of JIA increased with the number of antibiotic purchases from birth to the index date: for ≥ 1 purchases versus none, OR 1.6, 95% CI 1.3-1.9 with an upward trend in OR (p < 0.001). Antibiotic groups lincosamides and cephalosporins showed the strongest association with JIA (OR 6.6, 95% CI 3.7-11.7, and OR 1.6, 95% CI 1.4-1.8, respectively). Overall exposure to antibiotics before 2 years of age was associated with an increased risk of JIA (OR 1.4, 95% CI 1.2-1.6), with the trend test of OR (p < 0.001).

CONCLUSION

Previous early and repeated exposure to antibiotics may predispose individuals to develop JIA. Alternatively, the apparent association may reflect shared susceptibility to infections and JIA.

[Still's disease--juvenile arthritis with systemic onset]

Systemic onset juvenile idiopathic arthritis is a rare form of juvenile arthritis in which, contrary to autoimmune diseases in general, no association with a certain tissue type has been detected. Together with this fact, the lack of autoantibodies and the general symptoms belonging to the diagnostic criteria of the illness such as high fever, rather speak for its classification into autoinflammatory diseases. Treatment is usually started with anti-inflammatory drugs, often requiring combination with a systemic glucocorticoid. Recognition of interleukins 1 and 6 as central mediators in the pathogenesis of the disease has brought new possibilities for its treatment.

Variant MBL2 genotypes producing low mannose-binding lectin may increase risk of Bacillus Calmette-Guerin osteitis in vaccinated newborns

AIM

The aim of this study was to evaluate whether mannose-binding lectin (MBL) plays a role in the development of osteitis after Bacillus Calmette-Guerin (BCG) vaccination as a newborn.

METHODS

Blood samples were obtained from 132 former BCG osteitis patients, now aged 21-49 years, and analysed for MBL concentration and MBL2 genotype in a controlled setting.

RESULTS

Variant genotypes in the MBL2 gene were more common in the former BCG osteitis patients (42.4%) than in the population controls (32.3%, p = 0.033). However, MBL concentrations at the age of 21-49 years were not lower in these patients than in the controls in the same age group. The variant MBL2 genotypes were associated with low serum MBL concentrations, and moreover, MBL concentration was not measurable in two of those three patients who were homozygous for the variant MBL2 genotype. Low serum MBL concentrations were not associated with any illnesses in the medical history of the BCG patients, their siblings or children.

CONCLUSION

Preliminary evidence was found that variant, low-MBL-producing genotypes may be associated with the increased risk of BCG osteitis in vaccinated newborns.

Osteochondral lesions in children with juvenile idiopathic arthritis

BACKGROUND

Joint pain and swelling are typical symptoms in children with juvenile idiopathic arthritis (JIA) and these are often related to inflammation of the joint. Juvenile osteochondritis dissecans (JOCD), that is separation of a bone-cartilage segment from the articular surface, can manifest with similar symptoms.

FINDINGS

We studied thirteen cases of osteochondritis dissecans lesions (OCD) in children with JIA. There were nine girls and four boys with a mean age of 6.5 (2-12) years at the time of diagnosis of JIA. Mean time between diagnosis of JIA and manifestation of OCD was 5.5 (1-11) years. Indications for MRI were the presence of pain or discomfort in the joint, despite otherwise effective treatment, with no evidence from ultrasound examination of any obvious signs of active inflammation. The most common location of osteochondral lesion was the knee, although the ankle joint was affected in one case. Five patients had lesions in both knees. Operative treatment was needed in eight cases (joints).

CONCLUSIONS

Pain, and minor dysfunction of the joint are common complaints of children suffering from JIA. Earlier research has discounted the possibility of children who were not athletes presenting with this condition. However, this study demonstrates that these lesions also seem to be relatively common in patients with JIA. When there is no sign of inflammation, the possibility of OCD must therefore be considered in these children.

[Medical treatment of juvenile idiopathic arthritis]

Although etiology of juvenile idiopathic arthritis (JIA) is currently not known, better understanding of immunologic pathways of inflammation and the development of new therapies with biologic agents have remarkably improved the treatment of JIA. However, approximately 30% of the patients with JIA do not seem to response adequately to conventional anti-rheumatic drugs but the arthritis runs a continuously active course and may lead to the evolution of erosions. Such patients benefit from biologic agents, of which the longest clinical experience comes from anti-TNF therapies. Molecules targeting IL-1, IL-6 and B- and T-lymphocytes are also used in the treatment of severe JIA.

Topical treatment of uveitis resulting in adrenal insufficiency

The adverse effects of corticosteroids are well-known and occur more frequently when corticosteroids are used perorally or intravenously. The management of uveitis, which normally consists of topical corticosteroids and mydriates, can be challenging. We report a case in which continuous use of topical corticosteroids resulted in adrenal insufficiency and obesity.

CONCLUSION

When topical corticosteroids are used over longer periods, hypophysis-pituitary-adrenal (HPA) function should be carefully monitored.

[Loss of mobility in a child with Down syndrome]

Down syndrome is associated with the risk of various structural abnormalities or functional disturbances of organ systems, and with several abnormalities of the immune system. Screening and monitoring of congenital heart defects or orthopedic problems are managed and the increased risk to develop leukemia, diabetes of hypothyroidism is well known. The 3 to 6-fold incidence of juvenile idiopathic arthritis in Down syndrome compared with the general juvenile population is, however, less known. We describe a patient, for whom the diagnostic delay of juvenile idiopathic arthritis was eight years.

Total incidence and distribution of inflammatory joint diseases in a defined population: results from the Kuopio 2000 arthritis survey

OBJECTIVE

To study the incidence of inflammatory joint diseases in a defined population in Finland.

METHODS

We collected data for the year 2000 on a population of 87,000 inhabitants of Kuopio, Finland, of whom 20% were < 16 years of age. Information about the study was given through a local newspaper, and subjects attended one health center and 2 local hospitals for study. Inclusion criteria were that subjects have at least one peripheral joint with synovitis or signs of inflammation in sacroiliac, glenohumeral, or hip joints on the first visit. Incidence rates were calculated according to the diagnosis on the first visit, except for children, for whom diagnoses were established after 3 months' followup.

RESULTS

A total of 188 adult incident cases (138 women, 50 men) and 11 children (8 girls, 3 boys) satisfied the inclusion criteria. The incidence of all arthritides was 230/100,000 (95% confidence interval 198.9-263.9) for the whole population; 271/100,000 (95% CI 233.7-312.7) for adults and 64/100,000 (95% CI 31.7-113.8) for children. Among adults the annual incidence of rheumatoid arthritis (RA), ankylosing spondylitis (AS), psoriatic arthritis (PsA), reactive arthritis (ReA), other spondyloarthropathies (SpA), connective tissue disease (CTD), crystalline arthritis, viral arthritis, and undifferentiated arthritis were 36, 7, 23, 10, 13, 9, 19, 7, and 149/100,000, respectively. The mean age at diagnosis was 49.4 +/- 16.3 years for all cases of arthritis among adults, about the same for both women and men. The mean age at diagnosis was 59.7 years in RA, 31.5 years in AS, 48.7 years in PsA, 38.0 years in ReA, 36.5 years in other SpA, 36.1 years in CTD, 65.0 years in crystalline arthritis, 53.3 years in viral arthritis, and 48.3 years in undifferentiated arthritis. Four of 11 children had juvenile idiopathic arthritis (JIA). The incidence of JIA was 23/100,000 in the population < 16 years of age. Of the remaining cases, 3 children had antibodies against Sindbis (Pogosta) virus and 4 had a transient monoarthritis.

CONCLUSION

The overall incidence of arthritides among adults was slightly higher than previously reported from Finland. The incidence rates in the child population are in agreement with previous figures. These data are useful in planning the provision of health care.

Lumbar bone mineral density in normal subjects aged 3-6 years: a prospective study

Longitudinal studies on bone mineral density (BMD) accrual in young children are scarce. The purpose of the present study was to evaluate prospectively the development of spinal BMD in healthy Finnish children aged 3-6 y by dual-energy x-ray absorptiometry (DXA). Lumbar spine (L2-L4) areal BMD (g/cm2) was measured by DXA (Lunar DPX) in 20 children (10M, 10F) aged 3.3-6.9 y (median 4.8 y) at baseline and after a median follow-up of 1.0y (range 0.8-1.1 y). Apparent volumetric BMD (BMDvol, g/cm3) was calculated to minimize the effect of bone size on BMD in growing spine. At baseline, lumbar areal and volumetric BMDs (mean +/- SD) for males were 0.623+/-0.087 g/cm2 and 0.270+/-0.034 g/cm3, respectively, and for females 0.620+/-0.082 g/cm2 and 0.254+/-0.035 g/cm3, respectively. During the median follow-up of 1 y, lumbar areal and volumetric BMDs (mean +/- SD) increased in males by 4.7+/-2.7% (p < 0.01) and 3.5+/-3.5% (p <0.05), respectively, and in females by 7.2+/-5.3% (p <0.01) and 3.1+/-3.1% (p <0.05), respectively. No statistically significant difference in the BMD values was observed between the sexes.

CONCLUSION

A significant increase in both areal and apparent volumetric BMD was observed in children aged 3-6 y during a follow-up of I y. The increase in volumetric BMD indicated that there was a real accrual of BMD in growing spine measured by DXA. The present study provides prospective data on BMD accrual in young children for the evaluation of bone mass development in early childhood.

Galactan biosynthesis in snails: a comparative study of beta-(1--> 6) galactosyltransferases from Helix pomatia and Biomphalaria glabrata

Adult snails synthesize in their albumen glands a polysaccharide which is composed exclusively of D- or D- and L-galactose (Gal) residues which are interglycosidically linked by 1 --> 3 and 1 --> 6 bonds. It is the only carbohydrate source for embryos and freshly hatched snails. Two galactosyltransferases are described in this study which are most likely involved in the biosynthesis of this polysaccharide. One identified in Helix pomatia acts on oligosaccharides and could be used to synthesize a tetrasaccharide when the branched trisaccharide D-Gal-beta-(1 --> 3)-[D-Galbeta-(1 --> 6)]-D-Galbeta-1 --> OMe was offered as acceptor. This enzyme, requiring Mg++-and Mn++-ions for activity, introduced a linear beta-(1 --> 6) linkage at the terminal non-reducing ends and was not detected in Biomphalaria glabrata. The other enzyme, which introduced beta-(1 --> 6) linkages at subterminal D-Gal residues, thus forming branching points in the polysaccharide, was found in H. pomatia, Arianta arbustorum and B. glabrata with comparable activities. With the enzyme preparation of H. pomatia, up to four D-Gal residues were introduced into vicinal positions, forming single-membered side chains, if a hexasaccharide with five linearly beta-(1 --> 3)-linked D-Gal residues was offered as a acceptor. The multiple-branched structure formed is typical for snail galactans, making this enzyme a prime candidate for the branching enzyme in galactan synthesis. The enzyme activity could be solubilized and purified by affinity chromatography. In SDS-polyacrylamide electrophoresis, the Helix-derived eluate displayed two bands (68, 37 kDa) and that of Biomphalaria five bands (68, 63, 17.5; 15; 13 kDa). The purified material showed only 8% of the total activity of the crude extracts, but it could be shown that a phosphatase present in the crude extract can degrade UDP formed in the transfer reaction and thus drive the reaction to completion.

Development of tuberculin reactivity and sensitization to M. scrofulaceum and M. fortuitum in children BCG-vaccinated at birth

Since the incidence of tuberculosis is steadily declining in Finland and infections by environmental mycobacteria may be increasing, the aim of the present study was to evaluate the development of tuberculin reactivity and sensitization to environmental mycobacteria. Healthy Finnish schoolchildren aged 10.4-12.4 yrs (n=201) were tested with tuberculin purified protein derivative RT23, Mycobacterium scrofulaceum RS95 and M. fortuitum RS20 sensitins. The same children had been previously tested with the same antigens and methods at the age of 4-6 yrs in 1989. Rapid waning of tuberculin reactivity and decrease in sensitization to environmental mycobacteria were observed between 4-6 yrs. Both tuberculin and sensitin skin reaction sizes decreased significantly over the 6-yrs period. The mean tuberculin skin reaction size was 3.2 mm in diameter, which was significantly (p<0.001) smaller than the mean induration size (4.8 mm) at the age of 4-6 yrs. Similarly, the mean skin reaction sizes to M. scrofulaceum and M. fortuitum sensitins were 3.4 and 1.7 mm, respectively, which were significantly (p<0.001) smaller than 6 yrs earlier (mean 4.5 and 3.1 mm). The number of zero reactions to all antigens increased significantly during the follow-up period. Contacts with pets or farm animals were associated with larger reactions. In contrast, children suffering from allergic symptoms had smaller reactions. Contacts with mycobacteria, either with Mycobacterium tuberculosis or environmental mycobacteria, seem to be too rare to maintain tuberculin responsiveness and a high sensitivity to other mycobacteria. Different bacille Calmette-Guérin vaccine products and dosages used, the declining incidence of tuberculosis and geographical factors, which can influence environmental mycobacterial exposure, may explain the disparity between the present and previous Finnish studies.

Osteitis caused by bacille Calmette-Guérin vaccination: a retrospective analysis of 222 cases

To evaluate the frequency, clinical features, and prognosis of patients with osteitis caused by bacille Calmette-Guérin (BCG) vaccination, medical records from Finnish children based on nationwide registration from 1960 to 1988 were retrospectively analyzed. During the study period, three different BCG vaccine preparations were used. In 222 children, diagnostic criteria of BCG osteitis were fulfilled. The age at onset of BCG osteitis varied from 0.25 to 5.7 years. The most common sites of osteitis were metaphyses of the long bones. The lower extremity (58%) was affected more often than the upper (14%). Osteitis was situated in the sternum in 36 patients (15%) and in the ribs in 27 (11%). The frequency of BCG osteitis, but not the clinical parameters, was closely associated with the vaccine preparation used. Only 6 children were left with some sequelae. With adequate treatment, the prognosis for children vaccinated with BCG is good.

Influence of MPR revaccination on tuberculin and sensitin skin reactions in children

Many viral diseases, as well as viral vaccines, have a transient effect in depressing cell-mediated immunity. The study group consisted of 52 children, aged 6.0-6.3 years. Thirty (57%) of them had been revaccinated against measles, parotitis and rubella (MPR vaccination). In MPR-revaccinated children, the mean skin reaction sizes were 4.7 mm, 4.1 mm, 4.3 mm and 2.1 mm to tuberculin, Mycobacterium avium, M. scrofulaceum and M. fortuitum sensitins, respectively. In non-revaccinated children (n = 22), the respective mean skin reaction sizes were 3.0 mm, 2.8 mm, 2.9 mm and 0.8 mm. The difference between re- and non-revaccinated children was statistically significant with regard to reactions to M. fortuitum sensitin (p < 0.05). These results suggest that the influence of viral revaccination is different from natural infection or primary vaccination. The mechanism of stimulation of cell-mediated immunity--either specific or non-specific--is unknown.

Osteitis after newborn vaccination with three different Bacillus Calmette-Guérin vaccines: twenty-nine years of experience

Newborns in Finland have been vaccinated with Bacillus Calmette-Guérin (BCG) since the 1950s. Until the end of 1970 the vaccine was made from BCG strain Gothenburg by the Swedish BCG laboratory in Gothenburg and from 1971 on from the same strain in Copenhagen, Denmark. It was replaced by the Glaxo vaccine in 1978. Complications caused by BCG vaccination have been under follow-up, and the data have been collected from nationwide registers. In this study we analyzed the incidence rates of BCG osteitis between the years 1960 and 1988. From 1960 to 1970 the incidence rate was from 2.7 to 13.0/100,000 BCG-vaccinated infants (mean, 7.3; median, 6.9). The incidence increased during the years 1971 to 1978 when it varied between 15.3 and 72.9/100,000 BCG-vaccinated infants (mean, 36.9; median, 30.4). Since 1978 the incidence has varied between 1.7 and 10.1/100,000 BCG-vaccinated infants (mean, 6.4; median, 7.2). In Britain no reports of BCG osteitis have been published despite the use of the same Glaxo vaccine. Our results indicate that the incidence of BCG osteitis in a given population depends on the BCG vaccine used. The follow-up of BCG complications is an essential part of BCG vaccination program.

Development of bone mass and bone density of the spine and femoral neck--a prospective study of 65 children and adolescents

The bone mineral density (BMD, g/cm2) of the lumbar spine (L2-L4) and femoral neck was measured twice with a 1-year interval by dual energy X-ray absorptiometry (DEXA) in 65 healthy children and adolescents aged 7-20 years. In addition, the BMD values were corrected for the size of bones to obtain the bone volumetric density (BMDvol, g/cm3) using a method developed previously. The annual increases of BMD and BMDvol in both spine and femoral neck were most marked in females at the time of menarche (during the age of 11-13 years), and in males between the ages of 13 and 17 years. The males showed significantly higher values in their mean annual increment rates of femoral bone mineral content (BMC) and femoral neck width, whereas no differences in spinal parameters were found. The acquisition of bone mass and bone density stopped or markedly diminished before the age of 20 years, supporting the theory that the major portion of the peak bone mass is attained in late adolescence. We could not find any significant relationship between the increment rate of bone density, and physical activity or calcium intake. This study emphasizes the significant effect of puberty and genetic factors on the development of bone mass and density.

C-reactive protein in viral and bacterial respiratory infection in children

C-reactive protein (CRP) was studied in 209 children treated in hospital due to middle or lower respiratory tract infection with serologically demonstrated viral or bacterial aetiology. Of the 110 patients with serological evidence of bacterial infection, either alone or in association with viral infection, 52% had CRP > 20 mg/l, 35% > 40 mg/l and 15% > 80 mg/l. Of the 99 patients with serological evidence of viral infection alone, 35% had CRP > 20 mg/l, but only 12% > 40 mg/l and 5% > 80 mg/l. Nearly all, 88%, of the 25 patients with CRP > 40 mg/l in association with viral infection had either an infectious focus, specific microbial or non-specific laboratory evidence suggestive of bacterial infection. By calculating diagnostic parameters at 3 cut-off levels of CRP, the level 40 mg/l seemed more useful than 20 mg/l or 80 mg/l for differentiation between viral and bacterial infections. By using a CRP value of 40 mg/l as a screening limit sensitivity was 0.55, specificity 0.88, positive predictive value 0.76, negative predictive value 0.55, and likelihood ratios of a positive and negative test result 2.9 and 0.74, respectively. It is concluded that low CRP values do not rule out bacterial aetiology of respiratory infection in children. On the other hand viral infection without bacterial involvement is very improbable if CRP is > 40 mg/l. Our results suggest that high CRP values rule out viral infection as a sole aetiology of infection; bacterial infection and antibiotic treatment should be considered in these cases.

White blood cell and differential counts in acute respiratory viral and bacterial infections in children

White blood cell (WBC) and differential counts were studied in 201 children hospitalized for acute viral or bacterial respiratory infection. The aetiology of infection was studied with a comprehensive set of serological tests. WBC and granulocyte counts were higher in patients with bacterial infection than in those with viral infection. Lymphocyte counts, by contrast, had no such aetiological association. The 95% confidence limits for WBCs and granulocytes distinguished bacterial and pneumococcal cases completely from viral cases with no bacterial involvement. The sensitivity of WBC counts, as well as granulocyte or lymphocytes counts, for distinguishing bacterial from viral cases was low at all cut-off levels. Specificity, in contrast, was 86% and 95% for WBCs at the cut-off levels 15.0 and 20.0 x 10(9)/l, and 84% and 97% for granulocytes at the cut-off levels 10.0 and 15.0 x 10(9)/l, respectively. It is concluded that high WBC and granulocyte counts are clear evidence of the bacterial aetiology of respiratory infection, but low or normal values do not rule it out. Lymphocyte counts are of no value for distinguishing between viral and bacterial infections.

Skin test reactivity to atypical mycobacteria among healthy Finnish preschool children vaccinated with BCG vaccine at birth

Skin test reactivity to three mycobacterial sensitins (M. avium, M. fortuitum and M. scrofulaceum) was studied in 353 healthy children vaccinated with the BCG vaccine at birth. A significant waning of reactivity to all of the three sensitins was found to occur with increasing age. Revaccination against measles, parotitis and rubella had been given to 31 (9%) of the children, all aged > 5.5 years. They had significantly larger reactions sizes, which was contrary to what was expected. Children with atopic dermatitis (n = 19) had significantly smaller reaction sizes to the M. fortuitum sensitin. Neither respiratory viral infections during the preceding six months nor contact with pets or farm animals had any influence on reaction sizes. The variation of sensitin reactions was large in preschool children vaccinated with the BCG vaccine at birth. The diagnostic value of sensitin reactions in preschool children needs to be elaborated in clinical studies in children with clinically demonstrable mycobacteriosis.

Rapid decrease in tuberculin skin test reactivity at preschool age after newborn vaccination

A study of tuberculin sensitivity was performed in 353 children aged 4-6 years, all vaccinated at birth with British BCG vaccine. Significant waning of tuberculin reactions with increasing age was found (p < 0.05). In the age group < 4.5 years, the mean tuberculin reaction was 6.6 mm, in the age group 4.5-5.5 years 5.2 mm and in the age group of > 5.5 years 3.5 mm. The number of children with positive reactions (> or = 5 mm) was 165 (40%) and those with strong reactions (> or = 10 mm) 49 (14%). None of the latter children had active tuberculosis during a follow-up period of 12 months. Eighty-three (24%) of the children had no reaction. The children who had been revaccinated with the MPR vaccine against measles, rubella and parotitis (n = 31) had significantly larger tuberculin reactions than the non-revaccinated children. Atopic dermatitis or infections during the preceding six months did not have any significant influence on reaction sizes. Our results demonstrate that the variation in size of tuberculin reactions after BCG vaccination at birth is large. We conclude that tuberculin sensitivity wanes rapidly by the age of 4.0-6.3 years.