[Rebound (reactive) thymic hyperplasia after chemotherapy in children with lymphoma]. / Hiperplasia tímica de rebote posquimioterapia en niños con linfoma.

INTRODUCTION: Thymic regrowth after chemotherapy treatment has been reported in children with lymphoma, and in order to avoid misdiagnosing these cases as relapses, physicians should become familiar with rebound (reactive) thymic hyperplasia (RTH) and remain aware of its possible occurrence. We aimed to estimate the prevalence of RTH in children with lymphoma after completion of chemotherapy and to evaluate the clinical characteristics, outcomes, and the findings of computed tomography (CT) and gallium-67 (GA-67) scans in these patients. PATIENTS AND METHODS: We conducted a retrospective cross-sectional study by reviewing the health records of children with a lymphoma diagnosis managed at an outpatient paediatric oncology clinic in Jeddah, Saudi Arabia. RESULTS: Rebound thymic hyperplasia was detected in 51.9% of the lymphoma patients (14/27). It developed a median of 2.5 months after completion of chemotherapy (range, 2.0-4.25 months). Patients with RTH had significantly shorter treatment durations, and we found no significant differences between patients with and without RTH in sex, age at diagnosis, type of lymphoma or type of treatment received. All patients with RTH were asymptomatic, and routine laboratory tests did not detect any abnormalities in them. The findings of CT and GA-67 scans were highly suggestive of RTH. None of the patients with RTH had a recurrence, and RTH resolved spontaneously within a median of 6 months (range, 4.0-11.0). CONCLUSION: RTH was detected in ∼50% of children with lymphoma after completion of chemotherapy. A clinical evaluation and laboratory tests combined with imaging by CT and GA-67 can help identify RTH and rule out other lesions elsewhere.

67-Gallium SPECT/CT in febrile syndromes of unknown origin. / SPECT/TC con galio-67 en los síndromes febriles sin foco conocido.

INTRODUCTION AND OBJECTIVE: Febrile syndromes of unknown origin (FSUO) are complex processes in hospital practice. Their management includes an exhaustive medical history and examination, as well as an extensive number of biochemical tests. If these are inconclusive, diagnostic imaging techniques such as SPECT/CT with 67-Gallium Citrate (67Ga-SPECT/CT) could play an important role. We evaluated its role in the management of FSUO in our healthcare area. MATERIAL AND METHODS: We reviewed 57 patients who underwent a 67Ga-SPECT/CT due to a FSUO (32 women and 25 men, age range: 32-83 years old) obtaining scintigraphic findings, previous treatments and final diagnosis. Values of sensitivity, specificity, positive predictive values (VPP) and negative values (NPV) were obtained and compared with the results for PET/CT with 18Fluor-deoxy-glucose (18F-FDG PET/CT) found in the literature. RESULTS: The diagnoses found were: infection in 27/57 (47%), inflammatory disease in 15/57 (26%), neoplasm in 1/57 (1.75%) and patients without final diagnosis in 14/57 (24%). The statistical values of 67Ga-SPECT/CT were: sensitivity, specificity, PPV and NPV of 67%, 93%, 97% y 48%, respectively which were slightly lower than those found for the 18F-FDG PET/CT (86%, 52%, 70% and 92%, respectively). The diagnostic yield was 73% which increased to 80% in the patients who lacked empirical treatment. CONCLUSION: Despite the better results of 18F-FDG PET/CT, 67Ga-SPECT/CT behaved as a useful technique in the management of FSUO. It is advisable to use it if 18F-FDG PET/CT is not available.

SPECT/CT with radiolabeled somatostatin analogues in the evaluation of systemic granulomatous infections / SPECT/CT com análogos radiomarcados de somatostatina na avaliação de infecções granulomatosas sistêmicas

Abstract Objective: To evaluate SPECT/CT with radiolabeled somatostatin analogues (RSAs) in systemic granulomatous infections in comparison with gallium-67 (67Ga) citrate scintigraphy. Materials and Methods: We studied 28 patients with active systemic granulomatous infections, including tuberculosis, paracoccidioidomycosis, pneumocystosis, cryptococcosis, aspergillosis, leishmaniasis, infectious vasculitis, and an unspecified opportunistic infection. Of the 28 patients, 23 had started specific treatment before the study outset. All patients underwent whole-body SPECT/CT imaging: 7 after injection of 99mTc-EDDA-HYNIC-TOC, and 21 after injection of 111In-DTPA-octreotide. All patients also underwent 67Ga citrate imaging, except for one patient who died before the 67Ga was available. Results: In 20 of the 27 patients who underwent imaging with both tracers, 27 sites of active disease were detected by 67Ga citrate imaging and by SPECT/CT with an RSA. Both tracers had negative results in the other 7 patients. RSA uptake was visually lower than 67Ga uptake in 11 of the 20 patients with positive images and similar to 67Ga uptake in the other 9 patients. The only patient who did not undergo 67Ga scintigraphy underwent 99mTc-EDDA-HYNIC-TOC SPECT/CT-guided biopsy of a lung cavity with focal RSA uptake, which turned to be positive for aspergillosis. Conclusion: SPECT/CT with 99mTc-EDDA-HYNIC-TOC or 111In-DTPA-octreotide seems to be a good alternative to 67Ga citrate imaging for the evaluation of patients with systemic granulomatous disease.

Resumo Objetivo: Avaliar o estudo SPECT/CT com análogos de somatostatina radiomarcados (RSA) em infecções granulomatosas sistêmicas, em comparação com o estudo com gálio-67 (67Ga). Materiais e Métodos: Vinte e oito paciente com infecção granulomatosa sistêmica ativa foram estudados, incluindo tuberculose, paracoccidioidomicose, pneumocistose, criptococose, aspergilose, leishmaniose, vasculite infecciosa e uma infecção oportunista inespecífica. Vinte e três tinham iniciado o tratamento previamente ao estudo. Todos fizeram imagem de varredura e SPECT/CT, 7 deles pós-injeção de 99mTc-EDDA-HYNIC-TOC e os outros 21 pós-injeção de 111In-DTPA-octreotide. Todos os pacientes também fizeram cintilografia com 67Ga, exceto um, que fez biópsia guiada por 99mTc-EDDA-HYNIC-TOC. Resultados: Vinte e sete sítios de atividade foram detectados com 67Ga em 20 de 27 pacientes, também vistos nos estudos com RSA. Ambos foram negativos nos outros 7 pacientes. A captação de RSA foi visualmente menor que a de 67Ga em 11 de 20 pacientes positivos e similar nos outros 9. Um paciente que não pôde fazer cintilografia com 67Ga, fez biópsia guiada por 99mTc-EDDAHYNIC-TOC SPECT/CT em uma cavidade pulmonar com captação desse traçador, que foi positiva para aspergilose. Conclusão: SPECT/CT com 99mTc-EDDA-HYNIC-TOC ou 111In-DTPA-octreotide parece ser uma boa alternativa para o estudo com 67Ga na avaliação de pacientes com doença granulomatosa sistêmica.

Utilidad del citrato de galio 67 en el diagnóstico de fiebre de origen desconocido / Effectiveness of gallium 67 citrate in diagnosing fever of unkown origin

Se presenta el caso de un paciente con cuadro de 4 meses de evolución de fiebre intermitente, pérdida no cuantificada de peso y diaforesis nocturna. El examen físico reveló hepatoesplenomegalia sin otras alteraciones. Los estudios iniciales mostraron anemia macrocítica-hipocrómica, y las serologías para VIH, hepatitis B y hepatitis C fueron negativas. La TAC de cuello reportó adenomegalias cervicales subcutáneas bilaterales; a una de ellas se le tomó una biopsia, que resultó negativa para malignidad o infección. El objetivo de este reporte es ilustrar la utilidad del 67Gacitrato en el estudio de la fiebre de origen desconocido.

Presentation is made of the case of a patient with a 4-month history of intermittent fever, unquantified weight loss and night sweating. Physical examination revealed heptosplenomegaly, with no additional alterations. Initial studies showed macrocytic-hypochromic anemia; serology tests for HIV, hepatitis B, and hepatitis C were negative. CT of the neck reported bilateral subcutaneous cervical lymphadenopathy; biopsy was performed on one, which resulted negative for malignancy or infection. The purpose of this report is to illustrate the effectiveness of Ga-citrate 67 in the study of fever of unknown origin.

Galio 67 na febre reumática: experiência preliminar / Gallium-67 in rheumatic fever: preliminary report

Purpose­ To validate the importance of 67Ga imaging to diagnose activity in rheumatic fever carditis and in the follow-up of treated patients with the disease. Patients and Methods­ Thirty patients with rheumatic fever were studied. Fifteen males and 15 females aged 7 to 39 years old (median 16 years), were submitted to 67Ga imaging. The patients were divided into two groups. GA­ 20 pacients who received only clinical treatment and GB­11 patients (one from group A) submitted to surgical biopsy. In 12 patients from GA, sequential 67Ga imaging were also realized for the therapeutic follow-up. Fifty-five 67Ga images were reviewed subjectively by experienced observers and a semi-quantitative analysis processed in a dedicated computer was performed with ROI's of 10 x 20 pixels over the projection of the heart and right lung in 22 negative and 33 positive studies. Results­ Group A­In 19 patients (95%) the 67Ga uptake matched with the clinical evidence, EGC and echocardiogram results. In one patient (5,0%) the 67Ga study was negative, but there were clinical and EKG evidence of activity of the disease; from these data this case was then considered as false negative. Group B­ In 11 patients submitted to surgical biopsy, the clinical-scintigraphic-histologic correlation matched in 10 cases and mismatched in one. The semi-quantitative analysis of the 67Ga uptake with ROI's over the topography of the heart and right lung showed an percentage index heart x right lung of 114,5 ±17,5% (2s.d.) in normals and 158 ± 30% (2 s.d.) in patients with active carditis: these data had value in the therapeutic follow-up of 12 patients from GA, where occurred good correlation, in every case, of the 67Ga uptake index and clinical evolution and EKG find ings Conclusion­The 67Ga imaging is a non invasive diagnostic method with a good sensitivity to the diagnosis of activity in rheumatic carditis, to evaluate the therapeutic results and to define inactivity for surgical cases

Biópsia endomiocárdica e mapeamento miocárdico com gálio-67 no diagnóstico de miocardite ativa em crianças portadoras de miocardiopatia dilatada / Correlation between 67-gallium imagingand endomyocardial biopsy in children with severe dilated cardiomyopathy

Objetivo­Comparar os resultados da biópsia endomiocárdica (BE) e do mapeamento com 67Ga em crianças portadoras de miocardiopatia dilatada (MD), bem como os resultados obtidos em portadores de miocardite ativa (MA), submetidos à imunossupressão. Casuística e Métodos­44 crianças (24 do sexo feminino) portadoras de MD de importante repercussão clínica e hemodinâmica, com idades entre 10 meses e 15 anos (média = 2,6 anos) além de exames clínico e complementares habituais foram submetidos à BE sob anestesia geral através de biótomo introduzido pela veia jugular interna e a administraçao venosa de 67Ga na dose de 37 a 111 mEq. Os pacientes em que se verificou inflamação miocárdica de intensidade moderada e intensa (BE) receberam droga imunossupressora por periodo mínimo de seis meses, e então novamente submetidos à BE e a mapeamento com 67Ga...

Purpose­This study was designed to compare 67Ga imaging and endomyocardial biopsy (EB) in children with severe dilated cardiomyopathy (DC), as well as to evaluate the results in a group of patients with active miocarditis submitted to immunossupressive therapy. Patients and Methods­Forty-four pediatric patients with severe DC were studied. Twenty males and 24 females from 10 months to 15 year old (median = 2.6 years). All patients were submitted to a protocol including 67Ga uptake and EB. In patients submitted to immunossupressive therapy these procedures were repeated after siz months...