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.

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.

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

We report the case of a 57-year-old man, presenting with bilateral panuveitis, bilateral sacroiliitis, intermittent pyrexia and a pulmonary nodule. The patient had been under immunosuppressive treatment for 2 years for Behçet's disease. However, he did not fulfill the diagnostic criteria of Behçet's disease. Blood analysis showed a very high C reactive protein (CRP at 34 mg/dl). In view of severe intra-ocular inflammation, the anterior chamber was punctured. Polymerase chain reaction (PCR) on the aqueous humour and on the blood revealed the presence of Tropheryma whippelii DNA, an agent responsible for Whipple's disease. The patient was treated with ceftriaxone followed by trimethoprim-sulfamethoxazol for 1 year with good clinical and biological evolution. This case illustrates the difficulty to diagnose an atypical Whipple's disease. In cases of uveitis with atypical signs and/or not responding to the treatment, the internist must consider to perform an analysis of the ocular fluids.

11C-methionine PET for the diagnosis and management of recurrent pituitary adenomas.

PURPOSE: The detection of recurrent pituitary adenoma by magnetic resonance imaging (MRI) is rendered uncertain by the tissue remodelling that follows surgery or radiotherapy. We aimed to evaluate the contribution of PET with 11C-methionine (MET-PET) in the detection and management of recurrent pituitary adenoma. METHODS: Thirty-three patients with pituitary adenoma were evaluated postoperatively by MET-PET, either because of biological evidence of active residual tumour or because of MRI demonstration of non-functional adenoma growth. We studied 24 secreting adenomas and nine non-functional adenomas. RESULTS: In 30 patients, MET-PET detected abnormally hypermetabolic tissue. In 14 out of these, MRI did not differentiate between residual tumour and scar formation. In nine of these 14 cases, major therapeutic decisions were undertaken (radiosurgery and surgery). In another group of 16 patients, both MET-PET and MRI detected abnormal tissue. In one case, neither MRI nor MET-PET detected adenomatous tissue. Finally, abnormal tissue was detected in two patients on MRI solely. In these two cases, failure of MET-PET to reveal the adenoma was attributable to concomitant inhibitory therapy. The sensitivity of MET-PET and MRI varied as a function of the tumour type: all non-functional adenomas were localised by both modalities, while MET-PET detected all adrenocorticotropic hormone-secreting adenomas whereas MRI depicted only one of these eight lesions. Fifteen out of 17 patients treated by radiosurgery showed clinical improvement after treatment. CONCLUSION: We suggest that MET-PET is a sensitive technique complementary to MRI for the detection of residual or recurrent pituitary adenomas. It should gain a place in the efficient management of these tumours.

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

OBJECTIVE: To study the frequency of technetium-99m-positive ciprofloxacin scans (Infecton scintigraphy) thought to be specific for bacterial DNA in patients with arthritis and to assess the clinical relevance of positive scans. METHODS: Four groups of adults with arthritis were studied. Group 1: 53 patients with inflammatory arthritis, 36 with spondylarthropathy (SpA) and 17 with rheumatoid arthritis (RA); group 2: five patients with crystal arthropathy; group 3: those patients with osteoarthritis (OA) of the knee, wrist or spine; and group 4: 28 patients who had no arthritis but were being investigated for renal infection. Patients were injected with 10 mCi 99Tcm-ciprofloxacin with isotope uptake analysis at 4 h. Clinically swollen joints were assessed by a rheumatologist and the positive scans assessed by a physician in nuclear medicine. RESULTS: Increased Infecton uptake was noted in inflamed joints independent of the pathology. It was seen in 10 of 17 patients with SpA, 12 of 17 with RA, all five with crystal arthropathy, eight with knee OA, two with wrist OA, none with spinal OA and none in uninflamed joints. A close correlation between clinically swollen joints and articular Infecton uptake was noted (P = 0.0003), with the uptake being in the distribution of the synovial perimeter. Additional uptake was noted in the abdomen (n = 9) and pulmonary region (n = 2) of SpA patients. CONCLUSION: The Infecton scan is not specific for infection but may be a reliable procedure for identifying the presence and distribution of the inflammation within joints. It has the potential for monitoring the response of inflamed joints to treatment.

[The nuclear medicine department and the TEP/Biomedical Cyclotron unit]. / Le Service de Médecine Nucléaire et l'Unité TEP/Cyclotron Biomedical.

During the last 25 years, the clinical and experimental activity in nuclear medicine at Erasme hospital has been influenced by the implementation of positron emission tomography (PET) in 1990 as a method of brain functional investigation. The activity of the PET/biomedical cyclotron unit has been dedicated to various subjects in neurology, neurosciences, psychiatry, oncology and cardiology. This has been made possible by developments in radiochemistry. The radiochemistry laboratory has designed and produced original tracers such as 9-[(3-[18F]fluoro-1-hydroxy-2-propoxy)-methyl]guanine (FHPG), a tracer of viral thymidine kinase activity in gene therapy protocols. We have brought new applications of PET, such as its integration into stereotactic neurosurgical and radioneurosurgical techniques in order to improve their diagnostic and therapeutic performance in neurooncology. We have also conducted multiple studies on brain physiology and pathophysiology, in particular with the use of functional and metabolic brain mapping methods and the use of tracers of neurotransmission systems. The Department of nuclear medicine has also performed studies on bone metabolism and investigated in vivo imaging methods of infectious and immune processes.

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.

Soluble HLA-DR antigen levels in serum correlate with rheumatoid arthritis disease activity and the presence of disease-associated epitopes.

We investigated correlations between soluble HLA-DR (sHLA-DR) molecules and several clinical, biological and genetic parameters associated with rheumatoid arthritis (RA) disease activity. Serum sHLA-DR concentrations were determined in 146 samples from 89 RA patients by an ELISA format, using an antibody combination of mouse and rat monoclonal anti-human HLA-DR antibodies. The mean sHLA-DR serum level in RA patients was significantly increased with 277+/-19 ng/ml compared to 142+/-13 ng/ml of 80 healthy controls (P<0.001). In ascending order of significance, correlations were found between serum sHLA-DR and EULAR swelling and pain scores, Waaler-Rose, RA factor, ESR and CRP (P=0.025 to P<0.001). High sHLA-DR levels were defined above 374 ng/ml that was the 95% confidence interval of the controls. Thirty-seven blood samples (25%) in 31 RA patients were above this level. The EULAR pain and swelling scores, erythrocyte sedimentation rate (ESR), C-reactive protein (CRP) and RA factor were higher (P=0.044 to P<0.001) at the moment of high sHLA-DR concentrations, compared to the lower concentrations. Higher disease activity was further found in groups of RA patients respectively heterozygous or homozygous for the disease-associated epitope (Q)R/KRAA within the HLA-DRB1 chain, compared to the group without this epitope (P<0.017 for part of the results). Likewise, sHLA-DR was respectively 169+/-17 (no disease associated epitope), 324+/-34 (heterozygous) and 442+/-69 ng/ml (homozygous for the disease-associated epitope on HLA-DRB1 alleles) (P<0.017). In conclusion, this study shows significant correlations between serum sHLA-DR levels and RA disease activity parameters, as well as increased sHLA-DR in patients with disease-associated epitope on HLA-DRB1 alleles.

Evidence of autoantibodies to cell membrane associated DNA (cultured lymphocytes): a new specific marker for rapid identification of systemic lupus erythematosus.

OBJECTIVE: Autoantibodies to cell membrane associated DNA are described in systemic lupus erythematosus (SLE). The specificity of these antibodies differ from antibodies to nuclear DNA. METHODS: Using indirect immunofluorescence, a specific IgG was detected giving a characteristic pattern of continuous peripheral membrane fluorescence on cultured B-lymphocytes. RESULTS: This pattern was observed in 53 of 80 serum samples of SLE patients but absent in the serum samples of the control populations: 15 rheumatoid arthritis, 38 ankylosing spondylarthritis, 17 non-inflammatory osteopenic patients, and 224 blood donors. In 34 Sjögren syndrome's patients one only showed a positive test. The cmDNA specificity of these antibodies was confirmed by pattern extinction with DNAse but not RNase or protease pre-treatment of the cells. IgG to cmDNA, separated by absorption/elution from purified cmDNA immobilised on DEAE-nitrocellulose reproduced the immunofluorescence pattern pictures. Extensive serum depletion of anti-double strand or single strand DNA antibodies by absorption to cellulose bound ds- or ss-DNA affected marginally the pericellular fluorescence revealing some minor cross reactivity with nuclear DNA. Moreover, in SLE patients without detectable antibody to ds-DNA, pericellular fluorescence could be visible. CONCLUSION: This novel rapid immunofluorescence method may serve as an identification test of SLE patients. Given its positive (97.1%) and negative (92.9%) predictive value, sensitivity (66%) and specificity (99.5%), it improves on other diagnostic tests such as the detection of antibodies to Sm.

Growth behavior of human pancreatic carcinoma xenograft correlates with nuclear features.

Two human pancreatic ductal adenocarcinomas with different growth rates were serially transplanted into nude mice. Feulgen-stained 4 microns sections and imprints from the xenografts were studied with a VICOM automated image analysis system. After pooling the results from two passages, with three mice in each passage, it was shown that of 23 nuclear parameters measured the following were correlated with a fast tumor growth rate: in sections, a decrease in heterogeneity of the chromatin and an increase in perimeter and nuclear area; in imprints, an increase in lesser diameter, in mean grey level difference between second neighboring pixels, and in total integrated optical density (DNA content). Several parameters differed significantly between passages, and between animals in the same passage. These findings suggest that the growth speed of pancreatic tumors may be predicted by nuclear parameters.