Septic pulmonary emboli detected by 18F-FDG PET/CT in children with S. aureus catheter-related bacteremia.

PURPOSE: The role of 18F-fluorodeoxyglucose positron emission tomography-computed tomography (18F-FDG PET/CT) in the diagnosis of metastatic infectious foci in children with catheter-related blood stream infection has been hardly studied, although some authors have reported it benefit in the screening of metastatic foci in adult population. Septic pulmonary emboli are among the most difficult to identify, because many cases do not present pulmonary complaints or abnormal chest radiography. However, diagnosis of these foci has important therapeutic consequences. The purpose of this article is to describe the role of 18F-FDG PET/CT in the diagnosis of septic pulmonary embolism in children with S. aureus catheter-related bacteremia. METHODS: We report 3 children with S. aureus catheter-related bacteremia and normal chest X-ray at admission, in whom 18F-FDG PET/CT led to the diagnosis of unsuspected septic pulmonary emboli, with an impact on clinical management. RESULTS: All patients had hemophilia and implantable venous access ports and presented with fever and normal lung auscultation. Only 1 reported non-specific symptoms (undifferentiated left chest pain). All patients had normal chest X-ray on admission. Catheters were removed within 48 h after admission in 2 cases, and 5 days after admission in the last case, subsiding fever. In 2 children, paired blood cultures were not able to identify bacteremia. However, in all cases catheter tip and subcutaneous port cultures yielded S. aureus and PET/CT detected unsuspected pulmonary metastatic emboli. CONCLUSIONS: 18F-FDG PET/CT should be considered as a useful tool to diagnose septic pulmonary embolism in S. aureus catheter-related bacteremia, especially if conventional diagnostic imaging techniques have failed to reveal possible metastatic foci. Further studies are needed to clarify the usefulness of PET/CT performance in children with CRBSI.

[99mTc-MAA peritoneal scintigraphy in pleuroperitoneal comunication in peritoneal dialysis patients]. / Gammagrafía peritoneal con 99mTc-MAA en las comunicaciones pleuroperitoneales en pacientes en diálisis peritoneal.

Peritoneal dialysis is a fully-contrasted alternative for the treatment of end-stage renal disease although it is not exempt of complications. Peritonitis and exit-site infections are among the most frequent complications found. Pleural effusion secondary to pleuroperitoneal communication (PPC) is a serious and uncommon complication in these patients. We present the case of a 50-year old man diagnosed of end-stage renal disease undergoing treatment with peritoneal dialysis who presented progressive dyspnea and right pleural effusion. The peritoneal scintigraphy with (99m)Tc-MAA makes it possible to confirm communication of intraperitoneal dialysis fluid to the pleural cavity.

[Iatrogenic lung microembolism detected by 18FDG PET/CT]. / Microembolia pulmonar iatrogénica detectada mediante 18F-FDG PET/TC.

We present the cases of two oncology patients: a male with Hodgkin's disease after completion of chemotherapy, and a woman recently diagnosed of melanoma, who underwent positron emission tomography/computed tomography (PET/CT) with 18F-FDG for therapeutic monitoring and initial staging, respectively. In both cases, hypermetabolic foci of 18F-FDG in lung parenchyma were found, without morphologic abnormalities in CT. These findings would have been consistent with lung pathology in the absence of any anatomic correlation. Combined PET/CT interpretation was of lung microembolisms probably originated at the injection site.

[Treatment of malignant pheochromocytoma with 131I MIBG: a long survival]. / Feocromocitoma maligno tratado con MIBG I131:una larga supervivencia.

131I-metaiodobenzylguanidine (131I-MIBG) is a structural analogue of adrenal hormone norepinephrine employed to localise tumours derived of neural crest and in the treatment of malignant pheochromocytomas. Although the number of patients is low, in the revised literature there are objective remissions and reduction of hormonal activity, with symptomatic answers. However, the reduction of size of tumour only has been described in some times and hardly ever in the presence of osseous metastasis. We present one patient diagnoses of malignant pheochromocytoma with osseous metastasis, who was treated with 131I-MIBG. It was administrated a total dose of 1,800 mCu, with an excellent tolerance and short adverse symptoms. There were a partial tumour response and a complete hormonal response, with a survival of 30 years after the diagnoses.

[Follow-up of children and young adults with differentiated thyroid cancer treated with radioiodine]. / Seguimiento de niños y jóvenes adultos con cáncer diferenciado de tiroides (CDT) tratados con radioyodo.

This is a retrospective study carried out in a group of 30 patients with differentiated thyroid cancer (age at diagnosis equal to or less than twenty years old). The aim of the study is to evaluate outcome after 131I therapy. Patients were classified into three groups on the basis of initial surgery, pathology and scintigraphic results: group I (thyroid extent), group II (locoregional extent), and group III (distant metastatic disease). Clinical parameters, 131I scans, serum thyroglobulin determinations and 131I therapeutic administered doses were evaluated in the follow-up. Some other complementary techniques such as chest X-ray and pulmonary function tests are also described. Scintigraphic absence of thyroid tissue has been observed in 83% of the cases; high thyroglobulin level is still detectable in 34% of the patients as a single evidence of disease, and 21% remain without any abnormal clinical, scintigraphic or analytical findings. Total doses administered have increased in groups I, II and III respectively, and have also been inversely proportional to the extension of lymph node surgery. At present, all the patients are alive and in good general condition. According to the results obtained, we conclude that children and young adults with DTC should undergo periodical 131I therapeutic doses in case of positive scans (once total thyroidectomy has been realized, with or without lymph node resection depending on the extension of disease). In our experience, the use of radioiodine is effective and safe in the follow-up of children and youngs with DTC.