Biomedical subjects

J Aittoniemi

Publications and source records attributed to J Aittoniemi.

9 recordsLinked to original sources

PubMed2002

The significance of mannan-binding lectin gene alleles in patients with primary Sjögren's syndrome.

OBJECTIVE AND METHODS: To investigate the significance or mannan-binding lectin (MBL) gene alleles in patients with primary Sjogren's syndrome (pSS). Genotypes were determined in 65 pSS patients and 138 controls. RESULTS: No difference in MBL genotype or allele frequencies was detected between the pSS patients and controls. However, when the effect of MBL genotypes on the diagnostic findings in pSS patients was assessed, none of the eight patients with 52/w genotype fulfilled four (definite) Californian criteria (P = 0.007). Among these eight the Chisholm-Mason histological grade was > or = 3 in only three (P = 0.017). Furthermore, the MBL concentration was lower in patients with 52/w genotype compared to those with wild-type (w/w) genotype (P = 0.035). CONCLUSION: Our findings suggest that MBL structural gene polymorphisms do not influence on susceptibility to pSS. However, MBL may be associated with salivary gland destruction in pSS, and its concentration may be comparable with the intensity of inflammatory reaction. Further studies are warranted to clarify the possible mechanisms involved.

Adult↗

PubMed2001

Response to vaccination against different types of antigens in patients with chronic lymphocytic leukaemia.

We investigated responses to vaccination against pneumococcal polysaccharide, Haemophilus influenzae b (Hib) conjugate and tetanus toxoid antigens in 31 patients with chronic lymphocytic leukaemia (CLL) and 25 controls. While in the control group all antibody responses against different antigens were highly significant, in the patient group clear evidence for responsiveness was detected only in the case of Hib polysaccharide antigen. Certain CLL patient subgroups showed low reactivity against tetanus toxoid antigen. In conclusion, plain polysaccharide vaccines seem to be ineffective in patients with CLL. Conjugate vaccines, in turn, are immunogenic and may offer protection against infections caused by encapsulated bacteria in these patients. Further studies concerning an optimal vaccination scheme and clinical efficiency are warranted.

Aged↗

PubMed2001

Increased concentration of fecal alpha1-antitrypsin is associated with cow's milk allergy in infants with atopic eczema.

BACKGROUND: The use of fecal alpha1-antitrypsin in the monitoring of intestinal inflammation in infants with atopic eczema and food allergy was evaluated. METHODS: The study material comprised 26 atopic infants with confirmed food allergy. Fecal samples were collected before an elimination diet and 3 months later for the determination of alpha1-antitrypsin. RESULTS: Nine (35%) of the 26 patients demonstrated an increased fecal concentration of alpha1-antitrypsin (median 3 mg/g; range 2.8-6.4 mg/g). In all nine patients (100%) the oral cow's milk challenge was positive as opposed to only six (35%) in those with normal alpha1-antitrypsin concentration (P = 0.0024). No further connections between alpha1-antitrypsin and other food allergies were detected. As a result of an adequate elimination diet, the fecal concentration of alpha1-antitrypsin was normalized in seven patients, with a favourable clinical response in atopic eczema in six and no improvement in one patient. CONCLUSIONS: Our results indicate that serial determinations of fecal alpha1-antitrypsin provide a useful non-invasive tool for the detection and follow-up of intestinal inflammation in a certain group of atopic infants with cow's milk allergy and severe inflammation of the gut.

Dermatitis, Atopic↗

PubMed2001

Early identification of bacteremia by biochemical markers of systemic inflammation.

Group II phospholipase A2 (PLA2-II), procalcitonin (PCT) and C-reactive protein (CRP) are useful indicators of the severity of inflammation in various infections. To compare their discriminatory abilities at an early phase of bacteremia, PLA2-II, PCT and CRP were measured upon admission and 24-48 h thereafter in 29 patients with bacteremia, non-bacteremic bacterial or viral infections. The levels of PLA2-II and PCT were higher in bacteremia than in non-bacteremic bacterial or viral infections. PCT was highest upon admission, PLA2-II peaked at 12-24h, whereas CRP peaked one day later. At < or =24h, the AUC(ROC)s of PLA2-II and PCT were superior to those of CRP. Thereafter, the AUC(ROC)s of PLA2-II and PCT decreased and those of CRP increased. PLA2-II at cut-off level of 150 microg/L and PCT at 2-6 microg/L showed high sensitivity and specificity for bacteremia within the first 24h. In conclusion, PLA2-II and PCT are useful markers for early diagnosis of bacteremia. Devising analytical methods suitable for point-of-care testing would further enhance the clinical utility of the measurement of serum PLA2-II and PCT.

Adult↗

PubMed1999

The significance of IgG subclasses and mannan-binding lectin (MBL) for susceptibility to infection in apparently healthy adults with IgA deficiency.

The aim of this study was to investigate the significance of IgG subclasses and MBL for susceptibility to infection in association with IgA deficiency. The study population consisted of 139 apparently healthy adult blood donors with IgA deficiency and normal serum levels of IgG and IgM, and an increased susceptibility to infection demonstrated at a population level. Additionally, 216 controls matched for age and sex were investigated. IgG4 deficiency was more common and the mean level of IgG4 lower in persons with IgA deficiency than in the controls. No significant associations could be demonstrated between overt IgG subclass deficiencies and increased susceptibility to infection. However, when the mean concentrations of IgG subclasses were analysed with regard to medical history, that of IgG1 was lower in persons who reported recurrent viral respiratory infections, that of IgG3 in persons who had episodes of severe infection in their history, and that of IgG4 in persons who had recurrent mild respiratory infections, compared with those who had no particular history of infections. In contrast, MBL deficiency-alone or combined with that of the IgG subclass-was not associated with increased susceptibility to infection in persons with IgA deficiency. The results indicate that the proneness to infections observed in a population of otherwise healthy persons with IgA deficiency can only for a small part be accounted for by concomitant deficiencies of IgG subclasses. Contrary to expectations, no synergism between the deficiencies of IgA and MBL could be demonstrated.

Adult↗

PubMed1999

Opsonising immunoglobulins and mannan-binding lectin in chronic lymphocytic leukemia.

We investigated the influence of plasma concentrations of immunoglobulin G (IgG), IgA, IgM, IgG subclasses and mannan-binding lectin (MBL) on susceptibility to infection in patients with chronic lymphocytic leukemia (CLL). Of 28 patients with CLL, increased susceptibility to infection was recorded in nine. Four of them (44%) had hypogammaglobulinemia as opposed to only one (5%) of the 19 patients without increased susceptibility to infection (OR 14.4; 95% CI, 1.6-130). When the effect of IgG subclasses contributing to hypogammaglobulinemia was studied, only the decreased concentrations of IgG4 and IgG2 were associated with increased susceptibility to infection. They, in turn, were intercorrelated and also highly correlated with the concentration of IgA. In fact, when these parameters were studied by a multivariable model, only the decreased concentration of IgA was shown as an independent risk factor for infection (P = 0.03). The mean concentration of MBL was significantly higher in patients with infections than in those without (6.54 mg/l and 2.75 mg/l, respectively; P = 0.001). The monitoring of its concentrations might be useful in the follow-up of infectious morbidity in CLL.

Carrier Proteins↗

PubMed1998

Mannan binding lectin deficiency and concomitant immunodefects.

OBJECTIVE: To determine the prevalence of a mannan binding lectin (MBL) deficiency in children with increased susceptibility to infections and to investigate whether other coexisting immunodeficiencies affecting opsonisation are needed to render MBL deficiency clinically significant. PATIENTS AND METHODS: 343 serum samples were collected from 266 children with repeated infections, a single episode of severe infection, or prolonged symptoms relating to infection. The concentrations of MBL, immunoglobulin G (IgG), M (IgM), A (IgA), and IgG subclasses (IgG1-4) were analysed. RESULTS: MBL deficiency was found in nine children (3.2%), seven of whom had repeated infections or a single episode of severe infection. In two, initial symptoms and signs suggestive of infection eventually led to the diagnosis of an autoimmune disease--Still's disease in one and pauciarticular juvenile rheumatoid arthritis in the other. Among the children with MBL deficiency and infections, concomitant IgG subclass deficiency was detected in five and a transient low level of one or two IgG subclasses in two. Prevalence of an IgG subclass deficiency in children with MBL deficiency was higher than in those without (56% and 22%, respectively). CONCLUSIONS: MBL deficiency alone is not an independent risk factor for infection but may be manifested in association with another humoral immunodeficiency affecting opsonisation. Among children with MBL deficiency, those with juvenile rheumatoid arthritis were overrepresented. This calls for further study.

Adolescent↗

PubMed1997

Serum mannan-binding lectin (MBL) in patients with infection: clinical and laboratory correlates.

In this study, we determined the serum levels of mannan-binding lectin (MBL) in patients with suspected or documented infection to characterize the possible role of MBL in the susceptibility to infection. We also investigated the kinetics of MBL during the infection and correlated the concentrations of MBL with those of acute-phase reactants C-reactive protein (CRP) and group II phospholipase A2 (PLA2-II) and cytokines interleukin-1(IL-1). interleukin-6 (IL-6) and tumor necrosis factor alpha (TNF-alpha). The frequency of MBL deficiency in the patients with signs of infection did not differ from that of controls. In four patients with MBL deficiency, the infections were caused by common pathogens and the outcome was normal. The mean MBL concentration in the patients with signs of infection was significantly higher than in the healthy controls (9.88 and 4.48 mg/l, respectively; p < 0.05). The highest mean MBL concentration was observed in patients with clinically or microbiologically documented bacterial infection. During follow-up, the MBL concentration altered individually in different patients, but no particular change in pattern in the MBL concentration could be demonstrated in any patient group. Of the acute-phase reactants in the circulation, only CRP and IL-1 showed a weak, albeit significant, negative correlation with the concentration of MBL. In conclusion, the deficiency of MBL was not shown to be an independent risk factor for infection in the adult population studied. The concentration of MBL did not follow the change in pattern of other acute-phase reactants and cytokines during the acute phase response. Therefore, measurement of the MBL concentration as an acute-phase reactant is not useful in the diagnosis or follow-up of infection. On the other hand, the deficiency of MBL can be detected reliably by serological methods even during an infection.

Acute-Phase Reaction↗

PubMed1996

Age-dependent variation in the serum concentration of mannan-binding protein.

Mannan-binding protein (MBP) is an acute phase reactant, and its deficiency is associated with the common opsonic defect and suspectibility to infections and atopic constitution. The aim of this study was to investigate the changes occurring in the serum level of MBP in infancy and during later childhood. We studied the serum concentration of MBP in 611 Finnish children of different ages and 110 adults by using an enzyme immunoassay. In an analysis of successive serum samples from infants at the day of birth and at the ages of 1 and 5 months, and at 1 and 2 years, the serum concentration of MBP increased significantly after birth, and was at its highest (the mean and median were 8.13 and 8.49 mgl-1, respectively) at the age of 1 month. After that, it declined to the initial level until the age of 5 months. The MBP concentration continued to decrease during childhood, and after the age of 12 years the MBP values reached the adult level. In Finnish adults the mean and median concentrations of MBP were 4.48 and 4.02 mgl-1, respectively, which seem to be higher than those reported previously in other populations. The high concentration of MBP in infants may best be explained by exposure to novel environmental antigens in early childhood, which suggests a protective role for MBP during the period of immaturity of the immunosystem. In older children the high level of MBP can probably be explained by childhood infections and the ensuing need of MBP.

Acute-Phase Proteins↗