99mTC-white blood cell scintigraphy with SPECT/CT in the diagnosis of vascular graft infection. / Gammagrafía con leucocitos marcados y SPECT/TC en el diagnóstico de infección de prótesis vasculares.

AIM: Vascular graft infection is a rare complication with a high morbidity and mortality. Early diagnosis is essential to establish an adequate treatment. We assess the accuracy of 99mTc-WBC scintigraphy with SPECT/CT in the diagnosis of vascular graft infection. MATERIALS AND METHODS: We retrospectively analyzed thirty 99mTc-WBC scintigraphies with SPECT/CT performed in thirty patients with suspicion of vascular prosthesis infection. Studies were considered positive for graft infection if the intensity of activity involving the graft was greater than the liver or bone marrow activity (spine and pelvis). RESULTS: Final diagnosis of infection was established in 10 patients, based on Fitzgerald criteria. Scintigraphy was positive in 11 patients. No false negatives were obtained. The values of sensitivity and specificity were 100% and 95%, respectively, with a PPV of 91% and a NPV of 100%. Twenty five patients had a CT performed prior to scintigraphy, in 9 cases the result was positive and in the remaining 16 was negative. CT sensitivity and specificity obtained in our study were 62.5% and 76% respectively, with a PPV of 55.6% and a NPV of 81.3%. Diagnosis of infection led to prosthesis exeresis in 8 cases (all of them had a positive microbiological study of the extracted material), while the remaining 2 patients were treated with antibiotic therapy alone due to high surgical risk. CONCLUSION: Our results suggest a high accuracy for 99mTc-WBC scintigraphy with SPECT/CT in the assessment of clinically suspected arterial graft infection.

Respuesta hormonal y metabólica completa tras el tratamiento con yodo-131 metayodobencilguanidina en un caso de feocromocitoma maligno / Complete hormonal and metabolic response after iodine-131 metaiodobenzylguanidine treatment in a patient diagnosed of malignant pheochromocytoma

La metayodobencilguanidina radiomarcada es un análogo de la norepinefrina que se utiliza en la localización de tumores que expresan transportadores de dicha neurohormona, especialmente los derivados de la cresta neural y de origen neuroendocrino, y en el tratamiento de sus metástasis cuando estas no son quirúrgicas. En la literatura revisada se encuentran mejorías sintomáticas, asociadas a un descenso de los niveles hormonales, en un porcentaje no despreciable de casos tras el tratamiento con 131I-MIBG. Sin embargo, la remisión tumoral completa se ha descrito en muy pocas ocasiones y casi nunca en presencia de metástasis óseas. Presentamos un caso de feocromocitoma maligno que tras el tratamiento con 131I-MIBG (600 mCi) alcanzó una respuesta hormonal y metabólica completa a pesar de la existencia de metástasis óseas (AU)

Radiolabeled metaiodobenzylguanidine is an analogue of norepinephrine used to localize tumors that express the neurohormone transporters, specifically those derived from the neural crest having a neuroendocrine origin. It is also used to treat non-surgical metastases derived from them. A review of the literature revealed symptomatic improvements associated to a decrease in hormone levels in a significant percentage of patients after 131I-MIBG treatment. However, complete tumor remission has been described only in very few cases and hardly ever when bone metastases exist. We present a case of a patient diagnosed of malignant pheochromocytoma who achieved complete hormonal and metabolic response after 131I-MIBG treatment (600 mCi) in spite of the presence of bone metastases (AU)

[Complete hormonal and metabolic response after iodine-131 metaiodobenzylguanidine treatment in a patient diagnosed of malignant pheochromocytoma]. / Respuesta hormonal y metabólica completa tras el tratamiento con yodo-131 metayodobencilguanidina en un caso de feocromocitoma maligno.

Radiolabeled metaiodobenzylguanidine is an analogue of norepinephrine used to localize tumors that express the neurohormone transporters, specifically those derived from the neural crest having a neuroendocrine origin. It is also used to treat non-surgical metastases derived from them. A review of the literature revealed symptomatic improvements associated to a decrease in hormone levels in a significant percentage of patients after (131)I-MIBG treatment. However, complete tumor remission has been described only in very few cases and hardly ever when bone metastases exist. We present a case of a patient diagnosed of malignant pheochromocytoma who achieved complete hormonal and metabolic response after (131)I-MIBG treatment (600 mCi) in spite of the presence of bone metastases.

Metástasis pancreática y tiroidea detectadas con 18F-FDG PET/TAC en paciente con cáncer colorrectal / Pancreatic and thyroid metastases detected with 18F-FDG PET/CT in patient with colorectal cancer

Mujer de 53 años diagnosticada de cáncer colorrectal, quien recibió tratamiento quirúrgico y quimioterápico, tras 5 años de remisión completa presenta una evolución atípica de su patología oncológica. La utilidad de la PET/TAC con 18F-FDG ha sido fundamental para la detección de las recidivas, sospechadas y no sospechadas, y para la monitorización de la respuesta al tratamiento(AU)

A 53-year-old woman with diagnosis of colorectal cancer, who received surgical treatment and chemotherapy. After 5-years of complete remission, she showed an atypical oncological evolution. The utility of 18F-FDG PET/CT scan has been fundamental to detect suspected and unsuspected recurrence and to monitor response to treatment(AU)

Pancreatic and thyroid metastases detected with 18F-FDG PET/CT in patient with colorectal cancer.

A 53-year-old woman with diagnosis of colorectal cancer, who received surgical treatment and chemotherapy. After 5-years of complete remission, she showed an atypical oncological evolution. The utility of (18)F-FDG PET/CT scan has been fundamental to detect suspected and unsuspected recurrence and to monitor response to treatment.

[Non-invasive diagnosis of posttraumatic thoracic splenosis]. / Diagnóstico no invasivo de la esplenosis torácica postraumática.

Intrathoracic splenosis is a generally asymptomatic entity incidentally diagnosed after the completion of an Rx, CT scan or MRI for another reason. The performance of scintigraphy with (99m)Tc-labelled heat-denatured erythrocytes allows the noninvasive diagnosis of this entity and avoids more aggressive diagnostic techniques such as FNAP or thoracotomy. Because this splenic tissue may be partially or fully functioning and therefore may have some beneficial immune function for the patient, the management of this entity should be conservative. Radioisotopic scintigraphy with (99m)Tc labelled heat-denatured erythrocytes is the technique with the greatest specificity in the demonstration of splenic tissue. The presence of subpleural pulmonary nodules, associated or not with intra-abdominal nodules, together with the existence of previous partial or total splenectomy, traumatic or not, with or without associated rupture of the diaphragm, should raise suspicion of the presence of intrathoracic splenosis.

[Iodine uptake in the chest in the follow-up of well-differentiated thyroid cancer]. / Captación torácica de (131)I en el seguimiento del cáncer diferenciado de tiroides.

Differentiated thyroid cancer is a disease having a very good prognosis when treated adequately. Ablation treatment with (131)I is frequently adjunct to surgery in these patients since it improves survival. Radioiodine whole-body scan is one of the imaging modality of choice in the follow-up of patients with this kind of pathology. After ablation treatment of the thyroid gland, any radioiodine accumulation in a non-physiological location usually means the presence of functioning metastasis. Recognition of potential false-positives is essential to avoid unnecessary exposure to further radiation from repeated therapeutic doses of radioactive iodine. We report a case of uptake in the chest due to bronchiectasis, potentially masquerading as pulmonary metastasis.

[Experience with 123I-Iodobenzamide in the differential diagnosis of Parkinson's disease and Parkinson-plus disease]. / Experiencia con 123I-Iodobenzamida en el diagnóstico diferencial de enfermedad de Parkinson frente a Parkinson plus.

OBJECTIVE: To perform a descriptive analysis of the clinical and diagnostic implications of (123)I-IBZM SPECT in the patients studied in our center for movement disorders suggestive of Parkinson-Plus Disease (PP). SUBJECTS AND METHODS: (123)I-IBZM SPECT was performed in 46 patients referred from the movement disorders consultation due to suspicion of PP. According to their symptoms, they were distributed into 3 groups: 35 patients had atypical symptoms (AS) for Parkinson's Disease, 2 showed no response to standard therapy (NR) and 9 presented both factors (AS, NR). The results of SPECT were only assessed qualitatively. RESULTS: The (123)I-IBZM supported the diagnosis of PP in 15(42.9%) out of the 35 patients with AS. The (123)I-IBZM was pathological in one of the two NR patients. Regarding the third group of patients (AS+NR), the (123)I-IBZM was pathological in 6 cases (66.7%). In 95.7% of our sample (44 patients), AS with or without NR was the main factor leading to suspicion of PP and the (123)I-IBZM was altered in only 47.7% (22 patients). Of these 22 cases, the final diagnosis was PP (with high positive predictive value) in 20(91%). CONCLUSION: The study with (123)I-IBZM is useful in the clinical practice because it provides objective diagnostic information with implications for the treatment and prognosis of patients with suspicion of PP.

[Brain perfusion study in patients with systemic lupus erythematosus and neuropsychiatric symptoms]. / Estudio de perfusión cerebral en paciente con lupus eritematoso sistémico y clínica neuropsiquiátrica.

Neuropsychiatric manifestations in 25% to 70% of patients with systemic lupus erythematosus (SLE), generally in young people. The variability in its clinical expression and lack of diagnostic methods have hindered the diagnosis of Central Nervous System Lupus. When the literature was reviewed on this subject, an important variability was found between the Single Photon Emission Computed Tomography (SPECT) findings and the patient's clinical symptoms and disease course. The case we are presenting shows the usefulness of brain perfusion SPECT because it shows alterations in the central nervous system that are not detected with other imaging modalities.

[Prenatal diagnosis of hydronephrosis: utility of diuretic renography]. / Diagnóstico prenatal de hidronefrosis: utilidad del renograma isotópico diurético.

OBJECTIVE: To investigate the value of diuretic renography in patients with prenatally diagnosed unilateral hydronephrosis. MATERIAL AND METHOD: We reviewed 44 patients who underwent ultrasonography in the first week of life and 1 month after birth, and cystography and diuretic renography at 1 month to evaluate differential renal function and the diuretic washout pattern. Patients with vesicoureteral reflux were followed-up according to the protocol for this disorder. In the remaining patients, ultrasonography and/or diuretic renography was performed every 3-6 months. RESULTS: In 4/44 patients vesicoureteral reflux was detected as cause a of hydronephrosis. In the remaining 40 patients, diuretic renography showed a washout pattern not suggestive of obstruction in 32 (only one patient needed surgery due to pyohydronephrosis). An indeterminate washout pattern was detected in one patient (who required surgery due to worsening of the washout pattern). A pattern suggestive of obstruction was detected in seven patients, four of whom required surgery (three due to a decrease in differential renal function and one due to worsening of the degree of pelvic dilatation). CONCLUSIONS: Diuretic renography is highly useful in risk stratification and in the management of newborn infants with hydronephrosis since infants with washout patterns not suggestive of obstruction will rarely develop obstructive hydronephrosis and can initially be followed-up with ultrasonography alone. In indeterminate and obstructive patterns, however, close monitoring that includes diuretic renography is mandatory.

[Ischemia of right ventricle and cor pulmonale]. / Isquemia de ventrículo derecho y cor pulmonale.

48 year old man with chronic obstructive pulmonary disease (COPD) secondary to pulmonary hypertension with domiciliary non-invasive ventilation was seen. He came to the emergency department with acute exacerbation of COPD. The patient was admitted to the Cardiology Service with the diagnosis of congestive heart failure. Diagnostic imaging (chest X-ray, transthoracic Doppler-echocardiography, multidetector row spiral CT and myocardial perfusion imaging) revealed an enlarged right ventricle. ECG was consistent with right ventricular failure. The heart perfusion imaging (pharmacologic stress testing with dobutamine) showed cor pulmonale and right ventricle ischemia induced by drug stress with dobutamine. Although right ventricle myocardial chronic dysfunction rarely causes right ventricular failure, it can occur when cor pulmonale and ischemia heart disease are present.