Imaging with FDG labeled leukocytes: Is it clinically useful?

In vivo and in vitro labeled leukocytes have been shown to be very effective in detecting different infectious and inflammatory conditions. The model of labeled leukocyte imaging is based on the powerful mechanisms of chemotaxis exerted on activated leukocytes by chemo-attractants. The avidity of inflammatory cells for fluorodeoxyglucose (FDG) has led to the concept of labeling leukocytes with [18F]FDG ex vivo. This concept combines cell-bound radionuclide trafficking from the blood pool compartment to the lesion with the high resolution of positron emission tomography (PET) imaging. The further benefits of having a correlated anatomical map by implementing the acquisition on a hybrid PET/computed tomography (CT) device are obvious. The feasibility and the potential value of leukocyte PET(/CT) imaging in infection have been demonstrated. The available data suggest a high accuracy of the method. Still, leukocyte PET/CT should not be considered as the endpoint of infection imaging, since it only meets a part of the criteria of the ideal infection imaging agent. However, the common clinical need for specific detection of infection with anatomical precision, the availability of the components necessary for performing leukocyte PET/CT, their lack of toxicity or adverse effects and the absence of more superior tracers on the commercial market make it worthwhile to further investigate leukocyte PET/CT imaging in larger prospective series. The advantages of leukocyte PET/CT over the more conventional nuclear medicine and radiological methods makes this imaging tool likely to be useful in certain subsets of infected patients.SCOPUS: ar.jinfo:eu-repo/semantics/publishe

Renal Abscess: Filling in with Tc-99m Ciprofloxacin of Defects Seen on Tc-99m DMSA SPECT

Tc-99m DMSA SPECT and Tc-99m ciprofloxacin SPECT images were sequentially acquired (time span, 3 days) in a 21-year-old woman with clinical signs of an upper urinary tract infection, an inflammatory syndrome, and urine cultures positive for Escherichia coli. The patient had an undocumented history of pyelonephritis a few years earlier. A wedge-shaped defect seen in the lateral cortex of the left kidney on Tc-99m DMSA SPECT was filled in on the Tc-99m ciprofloxacin scan. These findings were in favor of an acute inflammatory process and not of a new episode of pyelonephritis or a structural abnormality. Contrast-enhanced computed tomography (CT) revealed the presence of an abscess at this site. To our knowledge, no such case of cold-hot kidney lesions on sequential Tc-99m DMSA and ciprofloxacin SPECT studies has been reported.SCOPUS: ar.jinfo:eu-repo/semantics/publishe

Voxel-based assessment of spinal tap test-induced regional cerebral blood flow changes in normal pressure hydrocephalus.

OBJECTIVE: Normal pressure hydrocephalus (NPH) is a cause of dementia that may be amended by medical intervention. Its diagnosis is therefore of major importance and the establishment of response criteria to cerebrospinal fluid (CSF) shunting is essential. One of these criteria is the clinical response to spinal tap. The accuracy of the spinal tap test could potentially be improved by adding neuroimaging of regional cerebral blood flow (rCBF) changes to the response criteria. Statistical parametric mapping (SPM) is a voxel-based method of image analysis that may be used to statistically assess the significance of rCBF changes. The objective of this study was to evaluate, by SPM, spinal tap test-induced rCBF changes in patients with NPH syndrome. METHODS: Forty patients with NPH syndrome underwent hexamethylpropylene amine oxime (HMPAO) brain single photon emission computed tomography (SPECT) before and after a spinal tap test (1-day split-dose protocol). The differences in rCBF between these pairs of scans were analysed by SPM in the whole group and between subgroups divided according to gait improvement at the spinal tap test. RESULTS: In the whole group of patients, there was no statistical difference between pre- and post-spinal tap SPECT images. SPM analysis of patients grouped as a function of their clinical response to the spinal tap test revealed a significant post-spinal tap rCBF increase in the bilateral dorsolateral frontal and left mesiotemporal cortex in clinically responding compared with non-responding patients. CONCLUSION: According to SPM analysis, gait improvement at the spinal tap test in patients with NPH syndrome is associated with an rCBF increase localized in the bilateral dorsolateral frontal and left mesiotemporal cortex.Clinical TrialJournal ArticleResearch Support, Non-U.S. Gov'tinfo:eu-repo/semantics/publishe

Future Diagnostic Agents

Timely and specific diagnosis of infectious diseases can be clinically challenging but essential for the patient's outcome. Laboratory tests, such as a blood culture or urine specimen, can detect the responsible micro-organism but cannot discriminate between sterile inflammatory disease and truly infectious disease. Imaging tests, like scintigraphic techniques, can pinpoint the infection in the body. There are a number of clinical scintigraphic tests from which to choose, and no single test is optimal for the various presentations of clinical infectious disease. The currently available radiopharmaceuticals often are not capable of distinguishing between sterile inflammation, and bacterial or fungal infections. Neutrophil-mediated processes, characteristic for both inflammatory and infectious processes, can be targeted in situ by radiolabeled leukocytes, antibodies or fragments, or even by cytokines and 18F-fluorodeoxyglucose. Unfortunately those techniques are not infection-specific markers, and ongoing research is in progress to tackle this problem. The most promising option in this respect is directly targeting bacteria or fungi with radiolabeled antibiotics or antimicrobial peptides. These theoretically highly infection-specific radiopharmaceuticals could be used for monitoring the success of antimicrobial therapy of infectious disease. Although results from preclinical experiments and pilot studies in patients are promising, radiolabeled anti-infective agents are not currently in routine clinical use and studies are continuing to prove their effectiveness for diagnostic imaging of infections in the future. © 2009 Elsevier Inc. All rights reserved.SCOPUS: re.jinfo:eu-repo/semantics/publishe

Relapse of a renal inflammatory pseudotumour associated with Wegener's granulomatosis.

We report the case of a 32-year-old patient with Wegener's granulomatosis (WG) associated with a (biopsy - proven) renal inflammatory pseudotumour (IPT) of the left kidney treated by a partial nephrectomy, glucocorticoids and immunosuppressive drugs, in whom a relapse of renal IPT was found 6 years after the diagnosis of the first IPT. The originality of this observation lies in the fact that a relapse of IPT has never been described and also in the fact that complete regression of the IPT relapse was obtained with immunosuppressive treatment, while renal IPTs are currently treated by total or partial resection of the kidney. Finally, we discuss the potential benefits of an integrated 18fluorodeoxyglucose PET/CT for the follow-up of WG, since this imaging technique contributed to the management of the present case.Case ReportsJournal ArticleSCOPUS: ar.jinfo:eu-repo/semantics/publishe

Infecton is not specific for bacterial osteo-articular infective pathology

SCOPUS: ar.jinfo:eu-repo/semantics/publishe

Evaluation of technetium-99m-ciprofloxacin (infection) for detecting sites of inflammation in arthritis

SCOPUS: ar.jinfo:eu-repo/semantics/publishe

A 'made in one piece' skeleton in a 22-year-old man suffering from sickle cell anaemia.

A 22-year-old African male with known sickle cell anaemia was referred by a Congolese medical centre with a request to improve his poor physical condition. He was unable to walk, stand or sit because his large joints and his spine were either ankylosed or very rigid. Radiographs showed joint fusion from the third to the fifth cervical vertebrae, of both hips, of the left knee, and a bilateral osteonecrosis of the humeral head. There was no scintigraphic evidence for an active osteomyelitis (99mTc-MDP (methyldiphosphonate) bone scan, Tc monoclonal antigranulocyte scan and 99mTc sulphur colloid scan). To improve his mobility the right femoral head was resected in June 1997; 14 days later the left femoral head was resected. Four months after the resection of the right hip, a right uncemented total hip prosthesis was implanted on this side. One month later the same type of hip arthroplasty was performed on the left side. During the postoperative rehabilitation period the patient regained autonomy. We have found no previous reports of such severe and multiple joint complications in a single patient suffering from sickle cell anaemia.Case ReportsJournal ArticleSCOPUS: ar.jinfo:eu-repo/semantics/publishe

Infection is not specific for bacterial osteo-articular infective pathology [1] (multiple letters)

SCOPUS: le.jinfo:eu-repo/semantics/publishe

An atypical case of Whipple's disease: Case report and review of the literature

SCOPUS: ar.jinfo:eu-repo/semantics/publishe