Application of the buccal micronucleus cytome assay on child population exposed to sinus X-ray.

PURPOSE: Diagnostic X-ray examinations of paranasal sinuses use a low-dose ionizing radiation to achieve medically indicated purposes. The effects of low-dose radiation are still controversial, making it a highly prioritized field of research. As there is a need to evaluate the effects of low-dose ionizing radiation and that children might be a more vulnerable population, we performed simultaneous physical dosimetry and buccal cell micronucleus cytome assay on pediatric patients before and after an X-ray examination of the sinuses. METHODS: The study comprised 20 subjects aged 11.9 ± 3.6 years, and BMI < 25 kg/m2. Physical dosimetry was performed using radiophotoluminiscent (RPL) glass dosimeters placed on four positions on the head. The buccal cell micronucleus cytome assay was performed before and 14 ± 1 days after the X-ray exam, to monitor DNA damaging, replicative, cytostatic, and cell death effects. RESULTS: The doses in the primary beam ranged 371-1106 µGy and were several fold higher than at the other positions on the head. As for biological changes, we did not observe any DNA damaging effects. However, a significant increase in cells with condensed chromatin was observed, indicating more cells undergoing early stages of apoptosis. We also observed inter-individual differences between the subjects. A correlation between the doses detected and biological effects was not observed. CONCLUSION: Although we did not observe significant increase in DNA damage, further studies are needed to increase the statistical power of the results and ensure patients' safety and optimal health care.

COMPUTED TOMOGRAPHY SCAN FOR DIAGNOSIS OF OSTEOARTHRITIS: RARE LOCALIZATION IN THE SHOULDER IN A TWELVE-YEAR-OLD BOY.

Acute osteomyelitis is pyogenic infection of the bone and bone marrow. We report a case of successful diagnosis and treatment in a 12-year-old boy with right shoulder joint osteoarthritis. On admission, he was febrile (39.0 ºC) with pain in his right shoulder. Laboratory and biochemistry findings were as follows: leukocytes 10.9x109/L; hemoglobin 122 g/l; fibrinogen 34.7; C-reactive protein 56.8. No changes were observed using conventional radiography. Computed tomography (CT) scan was conducted on the right limb using LightSpeed 16 slices in native and contrast series. The area of interest was shown on axial section, less dense fluid within the joint cavity with a thickened capsule and joint soft tissue swelling around the joint. On bone structures, CT morphological changes were not observed. After deterioration of the condition despite antibiotic therapy, surgery had to be performed. The purulent content was removed by surgery. Prolonged antibiotic therapy and rehabilitation led to improvement of the condition. At two-month follow-up, ultrasonography and CT scan showed that there were no pathologic changes, while magnetic resonance imaging showed minimal tissue fibrosis that did no require surgical treatment.

Application of dosimetry systems and cytogenetic status of the child population exposed to diagnostic X-rays by use of the cytokinesis-block micronucleus cytome assay.

Low-dose ionizing radiation used for medical purposes is one of the definite risk factors for cancer development, and children exposed to ionizing radiation are at a relatively greater cancer risk as they have more rapidly dividing cells than adults and have longer life expectancy. Since cytokinesis-block micronucleus cytome (CBMN Cyt) assay has become one of the standard endpoints for radiation biological dosimetry, we used that assay in the present work for the assessment of different types of chromosomal damage in children exposed to diagnostic X-ray procedures. Twenty children all with pulmonary diseases between the ages of 4 and 14 years (11.30 ± 2.74) were evaluated. Absorbed dose measurements were conducted for posterior-anterior projection on the forehead, thyroid gland, gonads, chest and back. Doses were measured using thermoluminescence and radiophotoluminescent dosimetry systems. It was shown that, after diagnostic X-rays, the mean total number of CBMN Cyt assay parameters (micronucleus, nucleoplasmic bridges and nuclear buds) was significantly higher than prior to diagnostic procedure and that interindividual differences existed for each monitored child. For the nuclear division index counted prior and after examination, no significant differences were noted among mean group values. These data suggest that even low-dose diagnostic X-ray exposure may induce damaging effect in the somatic DNA of exposed children, indicating that immense care should be given in both minimizing and optimizing radiation exposure to diminish the radiation burden, especially in the youngest population.

Primary DNA damage assessed with the comet assay and comparison to the absorbed dose of diagnostic X-rays in children.

The aim of this work is to assess DNA damage in peripheral blood lymphocytes of children prior to and following airway X-ray examinations of the chest using the alkaline comet assay and to compare data with the measured absorbed dose. Twenty children with pulmonary diseases, between the ages of 5 and 14 years, are assessed. Absorbed dose measurements are conducted for posterior-anterior projection on the forehead, thyroid gland, gonads, chest, and back. Doses are measured using thermoluminescent and radiophotoluminescent dosimetry systems. Differences between tail lengths, tail intensity, and tail moments as well as for the long-tailed nuclei before and after exposures are statistically significant and are dependent on the individual. The results demonstrate the usefulness of the comet assay as a measure of X-ray damage to lymphocytes in a clinical setting. Doses measured with both dosimeters show satisfactory agreement (0.01 mSv) and are suitable for dosimetric measurements in X-ray diagnostics.

Chest radiography findings in primary pulmonary tuberculosis in children.

Plain chest radiography plays a major role in the diagnosis and follow-up of pulmonary tuberculosis in childhood. The aim of our study was to investigate the distribution of characteristic chest radiographic findings at diagnosis in children with pulmonary tuberculosis. The age of the patients and the type and localization of radiographic changes at admission were retrospectively analyzed. We reviewed chest radiographs in 204 children admitted from January 1, 1991 until June 30, 1994 for newly diagnosed pulmonary tuberculosis. Mean age +/- SD was 6.4 +/- 4.2 years (range 0-14). The most common lesion was lymphadenopathy (found in 172 children, 84.3%). It was significantly more common in the youngest age group (0-4 years) and was more significantly present in the right hilo-mediastinal region. Parenchymal changes were found in 125 children (61.3%). They were also significantly more common in the young age group and in the right lung. Other less common lesions included pleuritis, atelectasis, destructive-cavitary lesions and miliary dissemination. In conclusion, the leading radiographic finding in pulmonary tuberculosis in childhood remains hilar lymphadenopathy, but parenchymal changes are clearly strongly present, and should be sought and appreciated in the diagnostic work-up for pulmonary tuberculosis in childhood.