[Role of bone gammagraphy in the diagnosis of secondary osteomalacia in a patient treated with tenofovir]. / Utilidad de la gammagrafía ósea en el diagnóstico de osteomalacia secundaria en un paciente en tratamiento con tenofovir.

It is reported a HIV infected patient under antiretroviral therapy including tenofovir therapy who was referred to the Nuclear Medicine Department to complete bone pain study. A bone scan was performed at 3 hours after the injection of 740 MBq of 99mTc-MDP, revealing an abnormal distribution with characteristic changes compatible with osteomalacia. In further analysis, a secondary hyperparathyroidism and osteomalacia were diagnosed in the context of Fanconi syndrome, an infrequent complication described in patients under treatment with tenofovir.

[Gallium-67 (Ga-67) scintigraphy in tuberculosis and Mycobacterium avium-M. intracellulare infections in patients with HIV infections]. / Rastreo con galio-67 (67Ga) en la tuberculosis y las infecciones por Mycobacterium avium-M. intracellulare en pacientes con infección por el VIH.

BACKGROUND: Diagnosis of mycobacterioses in HIV infected patients is sometimes difficult because of atypical findings. The aim of this study was to assess the utility of gallium scintigraphy in diagnosis of AIDS related mycobacterioses in patients with fever of unknown origin. PATIENTS AND METHODS: We retrospectively reviewed the scans of 220 HIV(+) patients with fever (176 males [80%] and 44 females) who were evaluated with conventional diagnostic procedures at least of a week before. RESULTS: Gallium scintigraphy was positive in 114 patients (51%) and negative in 106 (49%). Mycobacteria were isolated in 83 patients (38%), 75 of these patients (90%) had a positive scintigraphy (sensitivity 90%; specificity 71%). Positive predictive value was 66% and negative predictive value was 92%. Mycobacterium avium-M. intracellulare (MAI) and M. tuberculosis were diagnosed in 22 (29%) and 53 (71%) HIV(+) patients, respectively. Seventy one (94%) of 75 patients with mycobacterioses had gallium uptake in at least two localizations. CONCLUSIONS: 67Ga scintigraphy is very useful in HIV(+) patients with fever of unknown origin. A negative gallium scintigraphy makes unlikely the diagnosis of mycobacterioses.

Radionuclide assessment of right ventricular contractile reserve after acute myocardial infarction.

Conflicting data have been reported about the implications of a decreased right ventricular (RV) contractile reserve (i.e., a < 5% stress-induced increase in ejection fraction [EF]). If a reduced reserve corresponds to ischemia, it will probably be associated with an electrocardiographic marker of RV ischemia, stress-induced ST-segment elevation (increases ST) in leads V3R to V6R. To test this hypothesis, 98 asymptomatic postinfarction patients (27 with RV infarction) were assigned to a dobutamine stress test (maximal dose 40 micrograms/kg/min) with equilibrium radionuclide angiography and electrocardiographic study, including leads V3R to V6R. All but 11 patients underwent coronary angiography. A dobutamine-induced increases ST in VR leads was seen in 24 patients with and in 8 without RV infarction. This electrocardiographic sign was 75% sensitive and 84% specific for the diagnosis of proximal right coronary artery disease. It was 61% sensitive and 74% specific for the detection of reduced RV contractile reserve. Patients with RV infarction had reduced RVEF at rest (38 +/- 9%), but the mean contractile reserve was normal (12 +/- 12%). The contractile reserve was significantly smaller in patients with proximal versus distal or no right coronary artery disease. It was also smaller (P < 0.01) in patients with increased ST versus no increased ST. In conclusion, high doses of dobutamine are useful in assessing RV contractile reserve after acute myocardial infarction. In these patients, a reduced RV contractile reserve is related to proximal right coronary artery disease and is associated with stress-induced increased ST in VR leads.