Nuclear Imaging for Classic Fever of Unknown Origin: Meta-Analysis

Abstract

Several studies have assessed nuclear imaging tests for localizing the source of fever in patients with classic fever of unknown origin (FUO); however, the role of these tests in clinical practice remains unclear. We systematically reviewed the test performance, diagnostic yield, and management decision impact of nuclear imaging tests in patients with classic FUO. Methods: We searched PubMed, Scopus, and other databases through October 31, 2015, to identify studies reporting on the diagnostic accuracy or impact on diagnosis and management decisions of 18 F-FDG PET alone or integrated with CT ( 18 F-FDG PET/CT), gallium scintigraphy, or leukocyte scintigraphy. Two reviewers extracted data. We quantitatively synthesized test performance and diagnostic yield and descriptively analyzed evidence about the impact on management decisions. Results: We included 42 studies with 2,058 patients. Studies were heterogeneous and had methodologic limitations. Diagnostic yield was higher in studies with higher prevalence of neoplasms and infections. Nonneoplastic causes, such as adult-onset Still's disease and polymyalgia rheumatica, were less successfully localized. Indirect evidence suggested that 18 F-FDG PET/CT had the best test performance and diagnostic yield among the 4 imaging tests; summary sensitivity was 0.86 (95% confidence interval [CI], 0.81-0.90), specificity 0.52 (95% CI, 0.36-0.67), and diagnostic yield 0.58 (95% CI, 0.51-0.64). Evidence on direct comparisons of alternative imaging modalities or on the impact of tests on management decisions was limited. Conclusion: Nuclear imaging tests, particularly 18 F-FDG PET/CT, can be useful in identifying the source of fever in patients with classic FUO. The contribution of nuclear imaging may be limited in clinical settings in which infective and neoplastic causes are less common. Studies using standardized diagnostic algorithms are needed to determine the optimal timing for testing and to assess the impact of tests on management decisions and patient-relevant outcomes.

Access, knowledge and experience with fluorodeoxyglucose positron emission tomography/computed tomography in infection management: a survey of Australia and New Zealand infectious diseases physicians and microbiologists

“…Fluorodeoxyglucose‐positron emission tomography combined with X‐ray computed tomography (FDG‐PET/CT) imaging has been used for many years as an effective method to stage and restage malignancies . Several studies have demonstrated high sensitivity of FDG‐PET/CT for diagnosis of infection of prosthetic devices, osteomyelitis and determining the aetiology of pyrexia of unknown origin (PUO) . Small studies have also demonstrated high clinical impact of FDG‐PET/CT in patients with neutropenic fever (NF) of unclear cause, with benefits of de‐escalating or rationalising antimicrobials, of directing further investigation such as bronchoscopy or tissue sampling and establishing an aetiological diagnosis of NF .…”

“…1 Several studies have demonstrated high sensitivity of FDG-PET/ CT for diagnosis of infection of prosthetic devices, osteomyelitis and determining the aetiology of pyrexia of unknown origin (PUO). [2][3][4] Small studies have also demonstrated high clinical impact of FDG-PET/CT in patients with neutropenic fever (NF) of unclear cause, with benefits of de-escalating or rationalising antimicrobials, of directing further investigation such as bronchoscopy or tissue sampling and establishing an aetiological diagnosis of NF. 5,6 There is emerging evidence that FDG-PET/CT is more sensitive for invasive fungal infection (IFI), its dissemination and response to therapy compared to traditional computed tomography (CT).…”

A fever of unknown origin as a presenting symptom in toxoplasmosis: Back to earth

“…This nuclear imaging test has shown its utility in patients with FUO, along with reasonable performance [7].…”

Der Beitrag der 18FDG-PET in der Entzündungsdiagnostik

“…Ein weiterer Vorteil der FDG-PET ist die sensitive Detektion von malignen Erkrankungen, da diese in bis zu 25 % für die Entstehung von Fieber unklarer Genese verantwortlich sind. Auch Autoimmunerkrankungen werden durch die PET detektiert, wodurch die FDG-PET prädestiniert ist, die drei häufigsten Ursachen von Fieber unklarer Genese zu diagnostizieren, ein klarer Vorteil auch gegenüber der Leukozyten-Szintigrafie [24,48].…”