FDG-PET/CT activity leads to the diagnosis of unsuspected TB: a retrospective study

Abstract

ObjectiveMycobacterium tuberculosis infection leads to latent or active tuberculosis (TB). Increased uptake on 18F-fluoro-2-deoxy-glucose-positron emission tomography/computed tomography (FDG-PET/CT) has been reported in the lungs and lymph nodes of individuals with recent infection and active TB, but not in individuals without known recent exposure or suggestive symptoms. We describe five patients with lung nodules not suspected to be due to TB in whom abnormalities on FDG-PET/CT scans ultimately were attributed to TB infection.ResultsPatient records were searched using the words “positron emission tomography/computed tomography” and 24 codes for TB between 2004 and 2013. Patients with a diagnosis of TB and a PET/CT scan were included. Clinical and radiographic data were retrieved. PET/CT images were reviewed by an experienced radiologist. FDG-PET/CT scans revealed elevated FDG-uptake in lungs of five patients subsequently diagnosed with active (n = 3) or clinically inactive (n = 2) tuberculosis. Uptake magnitude was unrelated to disease activity. These findings suggest that tuberculosis latency may include periods of percolating inflammation of uncertain relationship to future disease risk.

Anton Ghon and His Colleagues and Their Studies of the Primary Focus and Complex of Tuberculosis Infection and Their Relevance for the Twenty-First Century

“…Much more recently, investigations such as positron emission tomography with concurrent computerized tomography that is able to detect, locate, and quantify neoplastic and inflammatory activity with increasing accuracy have been used to study metabolic activity in the mediastinal lymph nodes in individuals with probable persistent TB infection and have demonstrated activity in suspicious circumstances [56-58]. Other investigators using real-time polymerase chain reaction and immunochemistry have documented the presence of considerable amounts of M. tuberculosis constituents in these calcified lymph node lesions [59].…”

18F-FDG PET/CT contribution to tuberculous vertebral osteomyelitis diagnosis: a case report

“…Furthermore, SUVmax has been shown to be a sensitive and accurate marker for noninvasive evaluation of treatment response, thereby indirectly prompting early diagnosis of resistant Mycobacterium tuberculosis strains [ 2 , 3 ]. Finally, a recent study evaluating asymptomatic patients with high SUVmax lesions provided new insights in the TB latency period [ 4 ]. It is worthy to remember, however, that no discriminative SUVmax value exists able to differentiate active TB from other malignant or infectious lesions [ 5 , 6 ].…”

PET-CT for characterising TB infection (TBI) in immunocompetent subjects: a systematic review

“…Only animal studies in non-human primate models were eligible for inclusion; all other animal studies reviewed involved rapidly progressive infection without a defined latent phase. In total, six studies met eligibility criteria for inclusion -two studies were experimental, prospective non-human primate studies [15,16] and four studies were in humans, including three retrospective [17][18][19] and one prospective cohort study [20] (Table 2). Collectively, these studies reported on four areas for review: i. cross-sectional PET-CT features of TBI (all six studies) [15][16][17][18][19][20]; ii.…”

“…Collectively, these studies reported on four areas for review: i. cross-sectional PET-CT features of TBI (all six studies) [15][16][17][18][19][20]; ii. differences between TBI and active TB disease (two studies) [18,19]; iii. serial PET-CT features of progressive TBI (two studies) [15,16]; and iv.…”