Marcia Cristina Bastos Boechat

Dose evaluation for paediatric chest x-ray examinations in Brazil and Sudan: low doses and reliable examinations can be achieved in developing countries

Radiation protection in paediatric radiology deserves special attention since it is assumed that children are more sensitive to radiation than adults. The aim of this work is to estimate the entrance skin dose (ESD), the body organ dose (BOD) and the effective dose (E) for chest x-ray exposure of paediatric patients in five large units, three in Sudan and two in Brazil, and to compare the results obtained in both countries with each other and with other values obtained by some European countries. Two examination projections have been investigated, namely, postero-anterior (PA) and antero-posterior (AP). The age intervals considered were: 0-1 year, 1-5 years, 5-10 years and 10-15 years. The results have been obtained with the use of a software called DoseCal. Results of mean ESD for the age interval 1-5 years and AP projection are: 66 microGy (Instituto de Pediatria e Puericultura Martagão Gesteira--IPPMG Hospital), 41, 86 and 68 microGy (Instituto Fernandes Figueira--IFF Hospital), 161 microGy (Omdurman Hospital), 395 microGy (Khartoum Hospital) and 23 microGy (Ahmed Gasim Hospital). In the case of the IFF Hospital, the results refer, respectively, to rooms 1, 2 and for the six mobile equipments. The reference dose values given by the European Guidelines were exceeded in the Khartoum Hospital whilst in all the other hospitals results obtained were below CEC reference values and comparable with the results found in Sweden, Germany, Spain and Italy. The mean E for the same age interval was 11 microSv in the IPPMG, 6, 15 and 11 microSv in the IFF, respectively for rooms 1, 2 and the 6 mobiles, 25 microSv in the Omdurman Hospital, 45 microSv in the Khartoum Hospital and 3 microSv in the Ahmed Gasim Hospital. These are some examples of the large discrepancies that have been detected in this survey.

Paediatric x-ray examinations in Rio de Janeiro.

This work presents the results of a dose survey performed for paediatric patients and carried out in two large paediatric public hospitals in Rio de Janeiro city. The entrance surface dose (ESD) and the effective dose (ED) were evaluated for chest, skull, abdomen, lumbar spine, cervical spine and pelvis in antero-posterior (AP), postero-anterior (PA) and lateral (LAT) projections. For each examination, four age groups 0-1, 1-5, 5-10 and 10-15 years were studied. The DoseCal software was used to calculate these doses. Wide variations for the same type of examination and projection have been detected. These variations were evident, in Brazil, from previous work. In spite of the present results being still preliminary, they can give an idea of what paediatric ESDs are like in Brazil. Also, with respect to the entrance surface dose, some of the results are above the reference levels, which cause high ED, as well. On the other hand, the wide range of ESD reflects the disparity of radiographic techniques and demonstrates that the ALARA principle is not being applied in Brazilian hospitals and becomes a concern in terms of public health.

Dose measurements using thermoluminescent dosimeters and DoseCal software at two paediatric hospitals in Rio de Janeiro.

A dosimetric survey in paediatric radiology is currently being carried out at the paediatric units of two large hospitals in Rio de Janiero city: IPPMG (Instituto de Pediatria e Puericultura Martagão Gesteira, University Hospital of Federal University of Rio de Janeiro) and IFF (Instituto Fernandes Figueira, FIOCRUZ). Chest X-ray examination doses for AP, PA and LAT projections of paediatric patients have been obtained with thermoluminescent dosimeters (TLDs) and with use of a software package DoseCal. In IPPMG and IFF 100 patients have been evaluated with the use of the TLDs and another group of 100 patients with the DoseCal software. The aim of this work was to estimate the entrance skin dose (ESD) for frontal, back and lateral chest X-rays exposure of paediatric patients. For ESD evaluation, three different TL dosimeters have been used, namely LIF:Mg,Ti (TLD100), CaSO4:Dy and LiF:Mg,Cu,P (TLD100H). The age intervals considered were 0-1, 1-5, 5-10 and 10-15 years. The results obtained with all dosimeters are similar, and it is in good agreement with the DoseCal software, especially for AP and PA projections. However, some larger discrepancies are presented for the LAT projection.

Cholelithiasis and biliary sludge in Down's syndrome patients

CONTEXT AND OBJECTIVE Although studies have demonstrated increased frequency of gallbladder abnormalities among Downs syndrome (DS) patients in some countries, there is only one paper on this subject in the Brazilian literature. The aim of this study was to demonstrate the prevalence, clinical characteristics and evolution of lithiasis and biliary sludge among DS patients in a maternity and childrens hospital in Rio de Janeiro. DESIGN AND SETTING This was a cross-sectional study followed by a retrospective cohort study on all individuals with an ultrasound diagnosis of gallbladder abnormalities. METHODS 547 DS patients (53.2% male, 46.8% female) attending the Instituto Fernandes Figueira in 2001 underwent abdominal ultrasound examination at ages of between one day and three years (mean: five months). Clinical and ultrasound data were analyzed. RESULTS In 50 patients (9.1%), the ultrasound demonstrated gallbladder abnormalities (6.9% lithiasis and 2.1% biliary sludge). Spontaneous resolution was observed in 66.7% of the patients with biliary sludge and 28.9% with lithiasis. Cholecystectomy was carried out on 26.3% of the patients with gallstones. CONCLUSION The results from this study and comparison with the literature suggest that DS patients are at risk of developing lithiasis and biliary sludge and should be monitored throughout the neonatal period, even if there are no known risk factors for gallstone formation. Most frequently, these gallbladder abnormalities occur without symptoms and spontaneously resolve in most non-symptomatic patients. DS patients should be monitored with serial abdominal ultrasound, and cholecystectomy is indicated for symptomatic cases or when cholecystitis is present.

Cranial bone collapse in microcephalic infants prenatally exposed to Zika virus infection

Brazil has been experiencing an outbreak of Zika virus, a flavivirus transmitted by Aedes mosquitoes. Since October 2015, more than 4,000 infants,1 born to mothers suspected to have contracted this infection during pregnancy, have microcephaly1,2 and CNS malformations (figure 1), including parenchymal and periventricular calcifications, ventriculomegaly, and cortical migration anomalies.2 This suggests marked viral neurotropism. Upon performing CT, cranial malformations (figure 2) with a pointed occiput are also observed.Brazil has been experiencing an outbreak of Zika virus, a flavivirus transmitted by Aedes mosquitoes. Since October 2015, more than 4,000 infants,1 born to mothers suspected to have contracted this infection during pregnancy, have microcephaly1,2 and CNS malformations (figure 1), including parenchymal and periventricular calcifications, ventriculomegaly, and cortical migration anomalies.2 This suggests marked viral neurotropism. Upon performing CT, cranial malformations (figure 2) with a pointed occiput are also observed.

Doença da arranhadura do gato por Bartonella quintana em lactente: uma apresentação incomum

This case study reports a typical clinical course of cat-scratch disease (CSD) in an infant without epidemiological data and presenting bilateral submandibular lymphadenopathy. The authors describe clinical course, ultrasound images, diagnosis and prognosis. Polymerase chain reaction (PCR) detected and identified B. quintana in lymph node samples. B. henselae currently thought to be the causative agent of CSD was not detected. The PCR assays for B. quintana and B. henselae should be available for the investigation of lymphadenopathy, even if the infant has not had either cat or dog contact.

Escore tomográfico em pacientes com fibrose cística colonizados por Pseudomonas aeruginosa ou Staphylococcus aureus

OBJECTIVE To compare HRCT findings in cystic fibrosis (CF) patients chronically colonized with Pseudomonas aeruginosa or Staphylococcus aureus using the modified Bhalla CT scoring system, as well as to evaluate intraobserver and interobserver reliability of the method. METHODS This was a retrospective cross-sectional study involving 41 CF patients, 26 of whom were chronically colonized with P. aeruginosa (Pa group), and 15 of whom were colonized with S. aureus (Sa group).Two independent radiologists evaluated the HRCT scans of these patients using the modified Bhalla CT scoring system in two different moments. Intraobserver and interobserver reliability was calculated using the intraclass correlation coefficient (ICC). RESULTS There was good intraobserver and interobserver agreement (ICC > 0.8). Scores were higher in the Pa group than in the Sa group for observer 1 (mean, 13.50 ± 3.90; median, 13.5 vs. mean, 5.00 ± 5.28; median, 3.0) and for observer 2 (mean, 11.96 ± 5.07; median, 12.0 vs. mean, 5.07 ± 5.65; median, 5.0). In addition, HRCT findings, such as bronchiectasis, bronchial wall thickening, mucus plugging, generation of bronchial divisions, and mosaic attenuation/perfusion pattern, were more prevalent in the Pa group. CONCLUSIONS The modified Bhalla CT scoring system was reproducible and reliable for use in the evaluation of HRCT scans, allowing distinctions to be drawn between the two groups of patients under study. The higher scores in the Pa group provided evidence of greater pulmonary impairment in that group.

A computed tomography scoring system to assess pulmonary disease among premature infants

CONTEXT AND OBJECTIVE High-resolution computed tomography (HRCT) is considered to be the best method for detailed pulmonary evaluation. The aim here was to describe a scoring system based on abnormalities identified on HRCT among premature infants, and measure the predictive validity of the score in relation to respiratory morbidity during the first year of life. DESIGN AND SETTING Prospective cohort study in Instituto Fernandes Figueira, Fundação Oswaldo Cruz. METHODS Scoring system based on HRCT abnormalities among premature newborns. The affected lung area was quantified according to the number of compromised lobes, in addition to bilateral pulmonary involvement. Two radiologists applied the score to 86 HRCT scans. Intraobserver and interobserver agreement were analyzed. The score properties were calculated in relation to predictions of respiratory morbidity during the first year of life. RESULTS Most of the patients (85%) presented abnormalities on HRCT, and among these, 56.2% presented respiratory morbidity during the first year of life. Scores ranged from zero to 12. There was good agreement between observers (intraclass correlation coefficient, ICC = 0.86, confidence interval, CI: 0.64-0.83). The predictive scores were as follows: positive predictive value 81.8%, negative predictive value 56.3%, sensitivity 39.1%, and specificity 90.0%. CONCLUSION The scoring system is reproducible, easy to apply and allows HRCT comparisons among premature infants, by identifying patients with greater likelihood of respiratory morbidity during the first year of life. Its use will enable HRCT comparisons among premature infants with different risk factors for respiratory morbidity.

Avaliação das doses de radiação em uretrocistografia miccional de crianças

OBJECTIVE: To evaluate dose-area product, skin entrance dose and doses from fluoroscopy and radiography in voiding cystourethrography studies of pediatric patients. MATERIALS AND METHODS: Procedures performed in 37 patients by four physicians of the institution were evaluated. Measurements were performed with an equipment including an ionization chamber directly coupled to the x-ray tube window and an electrometer (Diamentor) connected to a computer for data collection. RESULTS: Some procedures heterogeneity was observed and guidelines for good radiographic techniques were not followed. On average, 11 radiographies are performed for each study, with extended fluoroscopy time delivering a higher average final dose than those reported in the literature. CONCLUSION: The adoption of radiography with high kilovoltage technique and restricted utilization of fluoroscopy can result in a significant reduction of doses during this procedure, considering that the major contribution to the final dose comes from fluoroscopy.

Positive reaction for cysticercosis and multicentric anaplastic oligoastrocytoma

IntroductionAn unusual case of positive immunological testing for cysticercosis in the cystic fluid obtained from an anaplastic oligoastrocytoma is presented.Case reportA 15-year-old boy was admitted with multiple brain lesions. The biggest was a cyst with a mural node and neurocysticercosis was suspected. In order to relieve intracranial pressure, the cyst was punctured and the immunological testing for cysticercosis was positive, reinforcing the clinical suspicion and leading to a clinical trial with albendazole and steroids. As the patient deteriorated the cystic lesion was removed and the diagnosis of anaplastic oligoastrocytoma was established. A second lesion was eventually approached and the histopathological diagnosis of both specimens concurred.DiscussionAlthough some authors believe that chronic inflammatory changes following neurocysticercosis could induce the formation of brain tumors, this association may be a mere coincidence. In our case no clinical evidence of a prior infestation by Cysticercus was found. In fact, an exhaustive examination of the specimens did not reveal any areas of inflammatory reaction. We believe that the similarity of the glioma and cysticercosis antigens may be the cause of the positive reactions in the cystic fluid.