Frequency of polymorphism -262 c/t in catalase gene and oxidative damage in Slovak children with bronchial asthma

INTRODUCTION

Bronchial asthma is a complex disease in which genetic factors, environmental factors and oxidative damage are responsible for the initiation and modulation of disease progression. If antioxidant mechanisms fail, reactive oxygen species damage the biomolecules followed by progression of the disease. Catalase is one of the most important endogenous enzymatic antioxidants. In the present study, we examined the hypothesis that increased oxidative damage and polymorphism in the CAT gene (-262 promoter region, C/T) are associated with childhood bronchial asthma.

PATIENTS AND METHODS

Genotyping of the polymorphisms in the CAT gene in healthy (249) and asthmatic children (248) was performed using polymerase chain reaction-restriction fragment length polymorphism. Markers of oxidative damage: content of sulfhydryl groups and thiobarbituric acid-reactive substances were determined by spectrophotometry in children.

RESULTS

The TT genotype of catalase was more frequent among the asthmatic patients (22.6%) than in healthy children (4.8%) (odds ratio=5.63; 95% confidence interval=2.93-10.81, P<.001). The amount of sulfhydryl groups decreased significantly and conversely, the content of thiobarbituric acid-reactive substances increased significantly in bronchial asthma and in catalase TT genotype compared to other catalase genotypes of this gene.

CONCLUSIONS

These results suggest that catalase polymorphism might participate in development of bronchial asthma and in enhanced oxidative damage in asthmatic children. Genetic variation of enzymatic antioxidants may modulate disease risk.

X-linked agammaglobulinemia caused by new mutation in BTK gene: a case report

AIM

Primary immunodeficiencies (PID) are becoming a recognized public health problem worldwide. The most important subgroup of these disorders are the antibody deficiencies. X-linked agammaglobulinaemia was the first described entity of this group and is characterised by early onset of recurrent bacterial infections, profound deficiency of all immunoglobulin isotypes and markedly reduced number of peripheral B-lymphocytes.

CASE REPORT

We report the case of a 10-year old boy with X-linked agammaglobulinaemia caused by a previously non-described mutation in BTK gene with typical clinical presentation but delayed diagnosis. Following diagnosis, substitution therapy with intravenous immunoglobulins was started and the clinical status of the patient improved.

CONCLUSION

We reported a case of X-linked agammaglobulinaemia with delayed diagnosis despite the typical anamnestic signs for primary humoral immunodeficiency. The disease was caused by a previously non-reported mutation in the BTK gene. Measurement of serum immunoglobulins should be performed in all children with recurrent, complicated respiratory infections as a screening test for humoral immunodeficiencies.

Immunomodulatory effect of pleuran (β-glucan from Pleurotus ostreatus) in children with recurrent respiratory tract infections

OBJECTIVES

Recurrent respiratory tract infections (RRTIs) represent a very important problem in daily clinical practice because of their significant contribution to morbidity in children. Several natural nutritional supplements have been used in the prevention of RRTIs, but the clinical efficacy of only a few preparations is supported by scientific evidence.

MATERIALS AND METHODS

In a double-blind, placebo-controlled, randomised, multicentre study, we have observed a group of 175 children (aged 5.65 ± 2.39 years) with more than 5 respiratory infections that occurred during the 12 months prior to the beginning of the study. Children were randomised into an active group, treated with Imunoglukan P4H® syrup (with pleuran-β-glucan from Pleurotus ostreatus and vitamin C), or a placebo group (vitamin C only). During the 3 visits, within a 12-month period, questionnaires were completed, and blood samples were examined for immune parameters.

RESULTS

In the active group, 36% of the children did not suffer from any respiratory infections throughout the treatment, compared to 21% in the placebo group (p<0.05). Imunoglukan P4H® also significantly decreased the frequency of flu and flu-like disease and the number of lower respiratory tract infections. Imunoglukan P4H® treatment resulted in a statistically significant modulation of humoral and cellular immunity.

CONCLUSIONS

Results from this study demonstrate that Imunoglukan P4H® is effective in the prevention of RRTIs in children. Furthermore, our results also revealed complex immunomodulatory activity of this product. This is the first double-blind, placebo-controlled study in children with RRTIs that has addressed the preventive effects of pleuran on morbidity caused by respiratory infections.

Cough reflex sensitivity in adolescents with diabetic autonomic neuropathy

Objective

Diabetic autonomic neuropathy (DAN) is one of the chronic complications of diabetes mellitus which can involve one or more organ systems. DAN without apparent symptoms is more often in childhood and adolescence. While heart rate variability (HRV) and Ewing's battery of cardiovascular tests are regarded as a gold standard for the diagnosis of DAN, the examination of cough reflex sensitivity (CRS) is another possibility. The aim of this study was to compare HRV and CRS in children with diabetes mellitus.

Materials and methods

Sixty one patients (37 girls, 24 boys) aged 15-19 suffering from diabetes mellitus type 1 completed the study. Based on HRV, patients were divided into 2 groups - with DAN (n = 25) and without DAN (n = 32), 4 patients were excluded because of ambiguous results. CRS was studied in each patient by inhalation of gradually increasing concentration of capsaicin.

Results

Subjects with DAN required a significantly higher concentration of capsaicin needed to evoke 2 coughs (median 625 μmol/l, IQR 68.4-625.0 μmol/l vs. median 29.3 μmol/l, IQR 9.8-156.3 μmol/l, P < 0.001) and 5 coughs (median 2500.0 μmol/l, IQR 1250.0-2500.0 μmol/l vs. median 312.5 μmol/l, IQR 117.2-625.0 μmol/l, P < 0.001) compared with those without DAN. Moreover, a strong negative correlation between HRV and CRS was established.

Conclusion

Diabetes mellitus lowers the cough response. Cough reflex sensitivity appears to be another sensitive method for the evaluation of DAN in diabetes.

Factors attributable to the level of exhaled nitric oxide in asthmatic children

Background

Asthma is a heterogeneous disease with variable symptoms especially in children. Exhaled nitric oxide (FeNO) has proved to be a marker of inflammation in the airways and has become a substantial part of clinical management of asthmatic children due to its potential to predict possible exacerbation and adjust the dose of inhalant corticosteroids.

Objectives

We analyzed potential factors that contribute to the variability of nitric oxide in various clinical and laboratory conditions.

Materials and methods

Study population consisted of 222 asthmatic children and 27 healthy control subjects. All children underwent a panel of tests: fractioned exhaled nitric oxide, exhaled carbon monoxide, asthma control test scoring, blood sampling, skin prick tests, and basic spirometry.

Results

FeNO and other investigated parameters widely changed according to clinical or laboratory characteristics of the tested children. Asthmatics showed increased levels of FeNO, exhaled carbon monoxide, total serum IgE, and higher eosinophilia. Boys had higher FeNO levels than girls. We found a significant positive correlation between FeNO levels and the percentage of blood eosinophils, %predicted of forced vital capacity, total serum IgE levels, and increasing age.

Conclusions

Various phenotypes of children's asthma are characterized by specific pattern of the results of clinical and laboratory tests. FeNO correlates with total serum IgE, blood eosinophilia, age, and some spirometric parameters with different strength. Therefore, the coexistence of atopy, concomitant allergic rhinitis/rhinoconjunctivitis, and some other parameters should be considered in critical evaluation of FeNO in the management of asthmatic children.

Cardiac autonomic control in adolescents with primary hypertension

Background

Impairment in cardiovascular autonomic regulation participates in the onset and maintenance of primary hypertension.

Objective

The aim of the present study was to evaluate cardiac autonomic control using long-term heart rate variability (HRV) analysis in adolescents with primary hypertension.

Subjects and methods

Twenty two adolescent patients with primary hypertension (5 girls/17 boys) aged 14-19 years and 22 healthy subjects matched for age and gender were enrolled. Two periods from 24-hour ECG recording were evaluated by HRV analysis: awake state and sleep. HRV analysis included spectral power in low frequency band (LF), in high frequency band (HF), and LF/HF ratio.

Results

In awake state, adolescents with primary hypertension had lower HF and higher LF and LF/HF ratio. During sleep, HF was lower and LF/HF ratio was higher in patients with primary hypertension.

Conclusions

A combination of sympathetic predominance and reduced vagal activity might represent a potential link between psychosocial factors and primary hypertension, associated with increased cardiovascular morbidity.

Staphylococcus intermedius--rare pathogen of acute meningitis

We report the first case of acute meningitis caused by a rare, atypical pathogen. An 11-month-old infant was admitted to hospital with clinical symptoms typical of acute meningitis. Cerebrospinal fluid analysis revealed an elevated neutrophil cell count and high proteins. Microbiological examination of the fluid confirmed an atypical cause of meningitis--Staphylococcus intermedius. Antibiotic therapy with cefotaxime was successful and the child made a full recovery.

Reproducibility of food atopy patch tests over time in the general child population

BACKGROUND

The atopy patch test (APT) is no longer an experimental method; it is increasingly being used as a standard diagnostic tool for the characterization of patients with aeroallergen- and food-triggered disorders. Some technical aspects of this test still remain to be answered. We aimed to study the reproducibility of this test over time in the general child population.

METHODS

In a general population of 118 children, we investigated the reproducibility of duplicate APTs with four food allergens in their native form, which were repeated at set intervals from the first test: 7 days (group 1), 14 days (group 2), and 21 days (group 3).

RESULTS

We observed very poor reproducibility on both sides of the back in all three studied subgroups. The reproducibility rates and Cohen's kappa values did not improve when we did not consider the side of the back. There were no differences in the prevalence of atopy between the subjects with reproducible and nonreproducible APT results. All three groups studied showed no difference in the prevalence rates of atopy. There was no relationship between APT and skin prick test positivity for the same allergen. Questionnaire-derived data about previous food-related reactions did not help in the evaluation of the doubtful nonreproducible APT results with food allergens.

CONCLUSIONS

Our results show that the reproducibility of food APTs is poor and unsatisfactory over time, and there is an urgent need for the development of optimal, stable, and good-quality APT testing substances.

Association of oxidative stress and GST-T1 gene with childhood bronchial asthma

There is increasing evidence that bronchial asthma is associated with increased oxidative stress. Reactive oxygen species are produced in each organism as by-products of several essential reactions and can damage biomolecules. Asthma is a complex chronic inflammatory disorder of the airways, with many candidate genes suspected as being important in its development. Glutathione S-transferase (GST) is such a gene due to its role in protection against oxidative stress. In the present study, we examined the hypothesis that increased oxidative stress and polymorphism in the GST-T1 gene are associated with childhood asthma. We found that the amount of sulfhydryl groups significantly decreased and the content of thiobarbituric acid-reactive substances increased in the group of asthmatic children, compared with healthy controls. The GST-T1 null genotype was more frequent among the asthma patients. These results suggest that the GST-T1 null genotype and increased oxidative stress may play a role in the asthma pathogenesis in children.

Cough reflex sensitivity in various phenotypes of childhood asthma

Cough is a major symptom in some children with asthma, but the relationship between cough and the severity of asthma is defined insufficiently. As cough represents common problem of pediatrics, several objective methods for its assessment were developed. Cough reflex sensitivity (CRS) test with capsaicin is one of the most important tools for studying cough. In the present study, we aimed to study the CRS in various phenotypes of childhood asthma. We found that, in general, CRS was increased in asthmatic children compared with controls. The most evident increase of CRS was observed during acute asthma exacerbation, in children suffering from asthma with concomitant allergic rhinitis, and in atopic asthmatics. Interestingly, we noted a significant decline in lung function after capsaicin CRS. Various laboratory and clinical characteristics of asthmatic children influence cough sensitivity to a different extent. Cough reflex sensitivity measurement can add valuable information beside the commonly used spirometric and inflammometric methods in the management of asthmatic children.

Successful treatment of extreme acute lead intoxication

Severe acute lead intoxications are rare and are associated with accidental or purposeful ingestion. There were only few cases of severe to fatal poisonings reported in literature in children. We report a case of acute lead intoxication in a child with extremely high lead blood level of 20.4 μmol/L (422.7 μg/dL), who was treated with chelation and in whom significant organ dysfunction did not develop. Documented significant high level above 3.37 μmol/L (corresponding to 70 μg/dL) in this patient persisted for approximately 24 h. Adequate, single or combined chelatation therapy in early phase of acute lead poisoning is essential for the further patient’s outcome.

Therapeutic approach to a child with acute respiratory distress syndrome: a report of two cases

The course of a respiratory disorder in a child may end up in respiratory failure. There are also acute non-respiratory diseases which have a great influence on the respiratory functions and often lead to the acute lung injury and sometimes to the acute respiratory distress syndrome (ARDS). A feature of respiratory function deterioration is changed in the surfactant system. We often see inhibition of its synthesis or damage to its structure. Therapy of children suffering from ARDS should be complex and rapid. Despite many recently published studies explaining the principle of this disorder, the mortality of ARDS is still very high (30-50%). There are several studies documenting successful administration of exogenous surfactant as part of a complex combined therapy of patients with ARDS, which leads to decreased mortality, improved oxygenation, and decreased need for aggressive artificial pulmonary ventilation. The authors of this article present their own experience with administration of exogenous surfactant in therapy of children with ARDS.

Food allergens and respiratory symptoms

Food allergy may be clinically expressed by a variety of respiratory symptoms, which can be provoked either by IgE- or cellular mediated reactions. Among the diagnostic procedures, newly introduced atopy patch test seems to be important for diagnosis of cellular, delayed immune reactions. We studied the prevalence of positive atopy patch tests with food and inhalant allergens and the correlation between the positivity of atopy patch tests and questionnaire derived atopic and nonatopic espiratory symptoms and diseases in an unselected children population. We found a correlation between the positive patch test result with wheat and cough after physical effort, allergic rhino-conjunctivitis, and bronchitis recidivans. The subjects with positive skin reaction to egg suffered from allergic rhino-conjunctivitis and bronchial asthma. Food and inhalant allergens play an important role in the induction and exacerbation of some respiratory allergic diseases. The positive correlation of positive results of skin tests and history of some respiratory diseases and symptoms also on the population level confirm the importance of these tests in the diagnostic work-up of these allergic diseases.

Changes of airway obstruction parameters in healthy children caused by mother's smoking during pregnancy

The present study was aimed at the assessment of the impact of mother smoking during pregnancy on changes of phase angle (phi) and T(me)/T(E) index in healthy children. A hundred and twenty seven children, divided according to age (<6 months and >6 months of age) and mother smoking anamnesis were investigated by noncalibrated respiratory inductive plethysmography in the supine position. We found statistically significant changes of phi (p<0.05) and T(me)/T(E) in healthy children of non-smoking mothers against a group of smoking mother's children of up to 6 months of age. These differences were not confirmed in children older than 6 months. Moreover, in the smoking mother group, we found statistically significant changes (P<0.05) of phi and T(me)/T(E) in children of up to 6 months of age in comparison with children older than 6 month. The results revealed a negative impact of mother smoking during pregnancy represented by changes in airway obstruction parameters, which appeared especially in the group of youngest children.

Exhaled carbon monoxide as a new marker of respiratory diseases in children

Among modern methods included in diagnostic algorithms for various diseases, analyses of expired breath and its condensate acquire increasing importance. Various markers can be determined in the exhaled air, especially volatile gaseous compounds: nitrogen oxide (NO), carbon monoxide (CO), hydrocarbons and 8-isoprostanes. In contrast to NO, CO can serve as a marker of inflammation and oxidation stress. The representation of CO in the exhaled breath (eCO) changes in various diseases of the respiratory and other systems. Among the respiratory diseases in which the use of eCO measurement seems to be perspective and beneficial are bronchial asthma, airways infections, cystic fibrosis, and primary ciliary dyskinesia. The observation of eCO concentrations represents a modern, simple, available, and well reproducible method for the diagnosis of many diseases of respiratory system in children and for the observation of progression, severity of the disease, and response to therapy.

Age-dependent changes of airway obstruction parameters

The study was aimed at the assessment of the physiological range of phi and Tme/Te indices in children of up to 24 months of age, as based on noncalibrated respiratory inductive plethysmography performed in the supine position. We also examined the dependence of these indices on children's age and sex. The study was carried out in 127 healthy children. The results of the study indicate a significant decrease of phi in children aged 7-24 months in comparison with children of up to 6 months of age (P<0.001). Similarly, values of Tme/Te were found significantly higher in the group of older children (P<0.05). We did not find any appreciable sex differences in both measured parameters. The results of this study suggest that the Tme/Te index might be more stable, less age-dependent parameter of the Respitrace measurement than the phase angle j, but further research and analysis to achieve a correct verdict are warranted.

The influence of autonomic neuropathy on cough reflex sensitivity in children with diabetes mellitus type 1

Diabetic autonomic neuropathy (DAN) is manifested by dysfunction of one or more organ systems. Its subclinical form (sDAN) can be recognized with the use of noninvasive cardiovascular reflex tests. As the cough reflex is mediated via autonomic nervous system, there is a reason to suppose that it can also be changed due to presence of sDAN. The aim of the present study was to assess cough reflex sensitivity (CRS) in diabetic children with and without sDAN. A CRS test was performed in 35 children suffering from diabetes mellitus type 1 and the results were compared with those from age-matched 27 healthy children. Cough was induced by inhalation of capsaicin aerosol in doubling concentrations (0.61-1250 micromol/l) for 400 ms each. CRS was defined as the lowest capsaicin concentration that evoked 2 or more coughs (C2 parameter) and 5 or more coughs (C5 parameter). We found that CRS in the whole group of diabetic children was not significantly different from that in healthy children [diabetic children--C2: 75.1 micromol/l (95% CI: 42.0-134.2 micromol/l)] vs. healthy children--C2: 72.4 micromol/l (95% CI: 75.7-644.8 micromol/l)]. However, a significant decrease (P=0.005) in CRS was found in diabetic children with sDAN [n=12; C2: 221.0 micromol/l (95% CI: 75.7-644.8 micromol/l)] compared with diabetic children without sDAN [(n=23; C2: 42.7 micromol/l (95% CI: 23.1-79.0 micromol/l)]. We conclude that testing cough reflex sensitivity might be a way to establish the presence of diabetic neuropathy.

Cough reflex sensitivity in children with suspected and confirmed gastroesophageal reflux disease

Experimental and clinical studies performed in adults revealed that gastresophageal reflux disease (GORD) is associated with an appreciable increase in cough reflex sensitivity (CRS). The association between respiratory diseases and GORD is also present in children, but there is little evidence that GORD without aspiration of refluxate (proximal reflux) is a frequent cause of cough in children. The aim of this study was to find out whether CRS in children with GORD will be changed compared with healthy children, and if so, to determine the role of proximal vs. distal reflux in these changes. CRS and 24-h esophageal pH monitoring were performed in 20 children of whom 13 had confirmed GORD and 7 were suspected to have GORD. The control group consisted of 27 healthy children. For assessing the CRS, each subject inhaled 12 capsaicin aerosol concentrations (0.61-1250 micromol/l) at 1 min intervals. CRS was defined as the lowest capsaicin concentration that evoked minimally 2 coughs (C2). CRS in the group of children with suspected GORD [C2: 17.0 micromol/l (6.4-45.6 micromol/l)] and with confirmed GORD [C2: 13.4 micromol/l (3.6-50.9 micromol/l)] were significantly elevated (P<0.05) compared with healthy children [C2: 72.1 micromol/l (25.5-203.9 micromol/l)]. According to the parameters of 24-h pH monitoring, a significantly higher exposure to acid was present in the distal compared with proximal oesophagus. CRS changes correlated negatively with the distal, but not proximal, esophageal acid exposure. In conclusion, CRS changes in children suffering from GORD are similar to those described in adult patients with GORD. It is plausible that the main role in increased CRS in children with GORD play episodes of distal acid refluxes.

Assessment of tidal breathing patterns for monitoring of bronchial obstruction in infants

Two parameters of tidal breathing, the ratio of time to reach peak tidal expiratory flow to the total expiratory time (Tme/TE) and the ratio of volume exhaled at peak tidal expiratory flow to the total exhaled volume (dV/VT) were used to assess lung function in 21 sedated infants (aged 6-14 mo) with different degrees of airway obstruction. These parameters were compared with airway resistance as percentage predicted (Raw%) and maximum expiratory flow at functional residual capacity corrected for lung volume (VmaxFRC/TGV). VmaxFRC/TGV values correlated significantly with Tme/TE (r = 0.630, p = 0.002) as well as with dV/VT (r = 0.728, p = 0.001). Raw% values showed only a weak correlation with dV/VT (r = -0.435, p = 0.048). We conclude that Tme/Te and dV/VT are both able to detect airway obstruction in infants and that these parameters correlate much better with the forced expiratory flow values obtained by the rapid thoracic compression method than with airway resistance, determined by body plethysmography.

Pressure sensor plethysmography: a method for assessment of respiratory motion in children

Noncalibrated respiratory inductance plethysmography has been used to measure respiratory function by calculation of the phase angle and, more recently, by determination of the ratio of each time to reach peak tidal expiratory flow to total expiratory time (TPEF/TE). Since TPEF/TE is known to be decreased in airway obstruction when derived from flow signals obtained by a pneumotachograph, we wanted to develop an alternative method to measure rib cage and abdominal respiratory movements. For this purpose, we used two pressure sensors attached to the skin above the umbilicus and in the right medioclavicular line at the fourth intercostal space: "pressure sensor plethysmography". We tested the ability of this method to assess thoracoabdominal asynchrony and TPEF/TE by comparison with respiratory inductance plethysmographic and pneumotachographic measurements in 30 children, aged 1-12 yrs, with airway obstruction. The mean difference (95% confidence interval (95% CI)) between phase angles obtained by respiratory inductance plethysmography and pressure sensor plethysmography was only -5.8 degrees (range -18.0 to +6.4 degrees). Similarly, all methods used to measure TPEF/TE agreed well: mean differences (95% CI) between pneumotachographic and respiratory inductance plethysmographic, pneumotachographic and pressure sensor plethysmographic, and respiratory inductance plethysmographic and pressure sensor plethysmographic measurements of TPEF/TE were +0.01 (range -0.05 to +0.06), -0.03 (-0.09 to +0.03) and -0.03 (-0.10 to +0.04), respectively. We conclude that pressure sensor plethysmography is a simple and noninvasive method, and suitable to measure thoracoabdominal asynchrony and TPEF/TE ratios as well as respiratory inductance plethysmography and pneumotachography.

Effects of atropine, acetylsalicylic acid, FPL 55712, and phentolamine on increased histamine responsiveness of cat lung strips under conditions of airway inflammation

Our recent in vitro studies on airway smooth muscles of cats with turpentine oil inflammation showed an increase of isometric tension of the lung strips to histamine application. This communication describes the effect of atropine, acetylsalicylic acid, FPL 55712, and phentolamine on the histamine contractions of the lung strips derived from control and experimental groups of cats. Pretreatment of the lung strips with atropine and acetylsalicylic acid had no significant effect on histamine induced contraction. FPL 55712 significantly decreased the mean values of isometric contractions after the low doses of histamine in experimental groups of strips. The isometric contractions after higher doses of histamine were not affected by FPL 55712 in both groups of strips. The significant increase of histamine contractions of the lung strips induced by experimental inflammation was reduced by phentolamine. The role of alpha adrenergic receptors in the increased responsiveness of the inflamed lung tissues to histamine is discussed.