Should scintigraphy be completely excluded from the diagnosis of periprosthetic joint infection?

AIM: To analyse the diagnostic performance of bone and leukocyte scintigraphy for periprosthetic joint infection before excluding the test from routine practice, and to analyse the possible benefit of bone marrow scintigraphy in inconclusive cases. MATERIALS AND METHODS: From 2012 to 2018, all patients with a total hip or knee arthroplasty who had a bone and leukocyte scintigraphy performed and underwent revision surgery were included. Bone marrow scintigraphy was indicated only in cases in which bone and leukocyte scintigraphy were inconclusive. Diagnosis of periprosthetic joint infection was confirmed by positive intraoperative cultures after revision surgery. RESULTS: A total of 105 patients were included. Eighteen patients had total hip arthroplasties (18.1%) and 86 had total knee arthroplasties (81.9%). Mean age was 74 years. Nineteen cases were diagnosed with a periprosthetic joint infection. Bone and leukocyte scintigraphy had 64% sensitivity and 97% specificity. Bone marrow scintigraphy increased sensitivity and specificity to 88% and 100%, respectively. CONCLUSION: Bone and leukocyte scintigraphy possesses high sensitivity and specificity for the diagnosis of chronic periprosthetic joint infection. The additional use of bone marrow scintigraphy significantly increases diagnostic performance. For these reasons, bone scintigraphy is reserved for inconclusive cases of chronic periprosthetic joint infection.

[An evolutionary study at 5 years of left ventricular systolic function in patients with an uncomplicated infarct]. / Estudio evolutivo de la función sistólica ventricular izquierda a los cinco años en pacientes con infarto no complicado.

INTRODUCTION AND OBJECTIVES: The aim of the present study was to compare the left ventricular ejection fraction in a first uncomplicated acute myocardial infarction before hospital discharge (initial ejection fraction) and 5 years later (late ejection fraction) and to evaluate the factors that may influence their possible changes. PATIENTS AND METHODS: Eighty-three patients (mean age: 52.2 +/- 7.5, range: 35-65 years) who had a first uncomplicated infarction were evaluated. Between 10 and 15 days after the acute episode, thallium perfusion scintigraphy, radionuclide ventriculography and coronary arteriography were carried out. The ventricular function was reevaluated after 5 years with radionuclide ventriculography. The population was classified according to the localization of infarction (anterior or inferior) and to the initial ejection fraction (< 30%, 30-50% and > 50%). The factors derived from predischarge exercise test, perfusion scintigraphy, radionuclide ventriculography and coronary arteriography that might have had an influence on ejection fraction changes were evaluated with bivariate and multivariate analysis. RESULTS: 1) left ventricular ejection fraction of anterior infarctions was lower than in inferior infarctions, both during the subacute phase (35.1 +/- 12.9 vs 48.1 +/- 12.1; p < 0.001) and after 5 years (41.3 +/- 15.1 vs 47.6 +/- 12.8; p = 0.006); 2) a significant increase in ejection fraction after 5 years was found in patients with anterior infarction (35.1 +/- 12.9 vs 41.3 +/- 15.1; p < 0.001), particularly in those with initial ejection fraction between 30-50% (38.8 +/- 5.9 vs 44.8 +/- 11.2; p < 0.001), and 3) no variable, either clinical or derived from exercise test, perfusion scintigraphy, radionuclide ventriculography or coronary arteriography, discriminated between the patients in whom ejection fraction decreased by more than 5% during follow-up nor those with anterior infarction and initial ejection fraction between 30-50% in whom ventricular function was improved after 5 years. CONCLUSIONS: Left ventricular ejection fraction of anterior infarctions shows a significant improvement after 5 years, particularly in the subgroups with initial ejection fraction between 30-50%. Predictive factors of such improvement have not been identified.