Current controversies in clinical management of postmenopausal osteoporosis.

Osteoporosis is a frequent disease in postmenopausal women. Despite the fact that fragility fractures cause many problems - a bio-psycho-social burden for the individual and an economic burden for the society - osteoporosis is still underdiagnosed and undertreated. Controversies exist concerning assessment with different tools for initiating a disease-specific treatment, patient monitoring with bone turnover markers, and treatment duration due to potential side effects in long-term treatment. This manuscript outlines and discusses these controversies and the presented cases, representatives for frequent clinical problems, may give guidance for the clinician in deciding how and how long to treat his/her patient. Re-evaluations of the patients on a regular basis are essential to warrant the necessity of treatment continuation and may improve patients' compliance.

Miscellaneous non-inflammatory musculoskeletal conditions. Gaucher disease and bone.

Gaucher disease (GD) is an inherited lysosomal storage disorder affecting multiple organs. Non-neuronopathic GD, the most common form, can present with hepatosplenomegaly, anaemia, bleeding tendencies, thrombocytopenia, skeletal pathologies, growth retardation and, in severe cases, with pulmonary disease. The bone manifestations include bone infarcts, avascular bone necrosis, lytic lesions, osteosclerosis, fractures due to osteoporosis and, rarely, acute osteomyelitis. Bone pain of varying intensity, fractures and joint collapses increase the patients' morbidity and impair their mobility and quality of life. Currently available therapies - enzyme replacement therapy and substrate reduction therapy - have shown to improve blood count and the visceral manifestations within a short time. Beneficial effects have also been documented on bone pain, bone crises and the extent of osteoporosis. The article focusses on the bone pathologies of GD including its pathophysiology, current diagnostics, clinical management and therapeutic effects of enzyme replacement therapy, substrate reduction therapy and bone-specific therapies.

Patients with Gaucher disease living in England show a high prevalence of vitamin D insufficiency with correlation to osteodensitometry.

AIM: Gaucher disease type 1 (GD-1) is the most prevalent lysosomal storage disorder and frequently causes osteopenia and osteoporosis. Adequate vitamin D levels are essential for bone health. The present study retrospectively analyzed 25-hydroxyvitamin D (25[OH]D) in outpatients with GD-1. PATIENTS AND METHODS: Sixty GD-1 patients living at home and with residence in southern or central England (34 men, 26 women), aged 17-85 years (mean 45.0 years) were seen at routine follow-up visits (range: 1-9, mean: 4.4) between January 2003 and July 2007. Overall, 264 blood samples, collected at different seasons of the year, were present for laboratory testing. The retrospective interpretation of vitamin D deficiency was based on different cut-off levels of 25(OH)D (<25 nmol/L, <50 nmol/L, <80 nmol/L) and the seasons of the year. Vitamin D sufficiency was defined as 25(OH)D >80 nmol/L. RESULTS: The mean+/-SD of 25(OH)D was 58.2+/-30.3. Degrees of vitamin D deficiency (<25 nmol/L, <50 nmol/L, <80 nmol/L) were present in 9.1%, 44.3%, 83.0%, vitamin D sufficiency (>80 nmol/L) in only 17.0%, respectively. A significant seasonal variation of 25(OH)D was present. Results of vitamin D deficiency for December-May were 15.7%, 63.8%, 92.9%, and for June-November 2.9%, 26.3%, 73.7%. The 25(OH)D values representing the seasonal nadir observed during the season December-May showed a significant correlation with T-scores and Z-scores of the lumbar spine and hip. Parathyroid hormone and 25(OH)D were inversely correlated. CONCLUSIONS: Vitamin D deficiency is frequent among GD-1 patients. To optimize treatment of GD-1 vitamin D supplementation should be recommended.

Posttherapeutic (131)I SPECT-CT offers high diagnostic accuracy when the findings on conventional planar imaging are inconclusive and allows a tailored patient treatment regimen.

PURPOSE: The purpose of this prospective study was to determine the diagnostic impact and influence on patient treatment of posttherapeutic (131)I SPECT-CT when the findings on planar posttherapeutic whole-body scintigraphy (ptWBS) were inconclusive. MATERIALS AND METHODS: A total of 53 SPECT-CT scans were performed in 41 patients with thyroid cancer after high-dose (131)I therapy (2.944 to 7.526 GBq (131)I) because of diagnostic uncertainty on ptWBS. Physiological uptake in the salivary glands, gastric mucosa, gut, nasal mucosa, urinary tract and liver were considered to be normal. Any other foci of increased (131)I uptake, except iodine uptake clearly located in the thyroid bed, were considered to be abnormal. The data were evaluated on a lesion and a patient basis. RESULTS: Regarding neck lesions, SPECT-CT provided a diagnostic impact in 26/90 lesions (28.9%) and confirmed the diagnosis in 64/90 lesions (71.1%). On a patient basis, SPECT-CT changed N status in 12/33 patients (36.4%), provided a diagnostic impact in 21/33 patients (63.6%) and led to a treatment change in 8/33 patients (24.2%). Regarding lesions distant from the neck, SPECT-CT confirmed the diagnosis in 62/71 lesions (87.3%) and had a diagnostic impact in 9/71 lesions (12.7%). On a patient basis, SPECT-CT changed M status in 4/19 patients (21.1%), had a diagnostic impact in 14/19 patients (73.7%) and led to a treatment change in 2/19 patients (10.5%). Considering all patients, SPECT-CT led to a treatment change in 10/41 patients (24.4%). CONCLUSION: Integrated SPECT-CT is a useful tool, especially in cases of diagnostic uncertainty and helps to individualize patient management.

Is there a role for scintigraphic imaging of bone manifestations in Gaucher disease? A review of the literature.

Gaucher disease is the most prevalent inherited, lysosomal storage disease and is caused by deficient activity of the enzyme beta-glucocerebrosidase. Bone and bone marrow alterations are frequent in the most prevalent non-neuronopathic form of Gaucher disease. Imaging of bone manifestations in Gaucher disease is performed by a variety of imaging methods, conventional X-ray and MRI as the most frequently and most important ones. However, different modalities of scintigraphic imaging have also been used. This article gives an overview on scintigraphic imaging with respect to bone manifestations in Gaucher disease discussing the advantages and limitations of scintigraphic imaging in comparison to other imaging methods.

Changes of bone metabolism in seven patients with Gaucher disease treated consecutively with imiglucerase and miglustat.

Bone manifestations are frequent in Gaucher disease (GD), the most prevalent lysosomal storage disorder. Currently, therapy with enzyme replacement (ERT) or substrate reduction (SRT) is available. We investigated changes of laboratory parameters associated with bone metabolism in GD patients switching from ERT to SRT. Seven GD patients consecutively treated with ERT and SRT were studied. All patients had different degrees of bone involvement. Laboratory results were acquired at the time of change from ERT to SRT (0 months) and while on SRT (6 months, 12-18 months). Markers of GD activity remained stable or showed statistically insignificant increases. Six patients had stable skeletal manifestations and reported no bone-associated symptoms. One patient presented progressive bone manifestations on magnetic resonance imaging and experienced increasing bone pain. Osteocalcin, alkaline phosphatase, and C-terminal telopeptide of collagen I were initially within the lower part of the normal range and decreased during SRT (alkaline phosphatase P = 0.0169, osteocalcin nonsignificant, C-terminal telopeptide of collagen I nonsignificant). Tartrate-resistant acid phosphatase 5b was initially normal or slightly increased, and macrophage colony-stimulating factor was within the normal lower range; both parameters remained stable. Interleukin-6 was elevated only in the patient with progressive bone disease. Macrophage inflammatory protein 1alpha (MIP-1alpha) was elevated without change after switching to SRT. MIP-1beta was within the normal range, and no values were above 85 ng/mL, indicative of active skeletal disease. From a clinical and metabolic point of view, most skeletal manifestations and bone-associated laboratory parameters remain stable after switch from ERT to SRT.

Sentinel node SPECT-CT in breast cancer. Can we expect any additional and clinically relevant information?

UNLABELLED: The AIM of this study was to determine the additional value of SPECT/CT in sentinel node scintigraphy in breast cancer. Furthermore, it was our question to determine, whether the low-dose computed tomography component (LD-CT) can be used for axillary lymph node staging of clinically negative patients. PATIENTS, METHODS: 51 patients with invasive breast cancer <3 cm in diameter were included in our prospective investigation. SPECT/CT was performed on a dedicated scanner 30 minutes after subareolar injection of (99m)Tc-Nanocoll. Axillary staging with CT(LD) was performed using standard CT-criteria. SLN were allocated to an axillary level using SPECT alone and SPECT/CT. Additionally, the number of SLN on CT(LD) corresponding to the scintigraphic hot node was notified for each patient and compared to the number of SLN found with the gamma probe. RESULTS: In 45/51 evaluable patients SLN could be localised in level I in 43 patients and in level II in two patients (all positive) using SPECT-CT, whereas a clear allocation could not be obtained by SPECT alone. The number of SLN was discrepant between SPECT and CT(LD) in 13/45 patients. The number of SLN detected with the gamma probe (n = 68) not significantly differed from the number of SLN detected by CT(LD) (n = 65) but was significantly higher than with SPECT (n = 51). CT(LD) yielded a sensitivity of 35.7%, a specificity of 83.9%, a positive predictive value (PPT) of 50%, a negative predictive value (NPV) of 74.3% and a diagnostic accuracy of 68.9% for axillary staging with CT(LD). CONCLUSION: The additional information of SPECT/CT allows a more accurate characterization of the SN concerning size, depth and anatomical location. CT(LD) when performed during (99m)Tc-Nanocoll sentinel-SPECT/CT is not suitable for axillary staging in breast cancer patients with clinical negative axilla due to its low sensitivity and moderate specificity. Therefore, it does not influence the decision for SNB or ALND. The limited resolution of SPECT leads to an underestimation of the number of SLN compared to CT(LD) and the gamma probe.

Receptor activator of nuclear factor kappaB ligand and osteoprotegerin in men with thyroid cancer.

BACKGROUND: Suppressive thyroid hormone therapy is generally a lifelong treatment for patients with differentiated thyroid cancer (DTC). However, long-standing thyrotropin (TSH) suppression is a risk factor for osteoporosis. Osteoprotegerin (OPG) and receptor activator of nuclear factor kappaB ligand (RANKL) are central regulators of bone turnover. The aim was to analyze the effects of a suppressive thyroid hormone therapy in males with DTC on the OPG/RANKL system and on bone metabolism. PATIENTS AND METHODS: The OPG and soluble RANKL (sRANKL) were determined in 40 men (mean age, 53.2 years) with DTC on suppressive thyroid hormone therapy (TSH; 0.053 +/- 0.037 mU L(-1), duration 5.7 +/- 4.4 years) and 120 healthy controls matched for age. The markers of bone metabolism were C-terminal telopeptide of type I collagen in serum (sCTx) and osteocalcin (OC). RESULTS: The control group had OPG values (mean +/- SD) of 1.9 +/- 1.0 pmol L(-1) and sRANKL values of 0.40 +/- 0.62 pmol L(-1). In patients with DTC, results for OPG were 3.03 +/- 1.04 pmol L(-1) (P < 0.05) and for sRANKL were 0.13 +/- 0.16 pmol L(-1) (P < 0.05). The control group presented values for sCTx of 2669 +/- 1132 pmol L(-1) and for OC of 17.89 +/- 6.5 ng mL(-1). Patients with DTC on suppressive thyroid hormone therapy had increased sCTx values of 3810 +/- 2020 pmol L(-1) (P = 0.03) but comparable OC values of 19.21 +/- 7.67 ng mL(-1) (NS). CONCLUSIONS: Suppressive thyroid hormone therapy in men with DTC increased bone degradation and induced significant changes in the OPG/RANKL system. These changes include, besides the risk of osteoporosis, possible negative effects on the vascular function and an increased risk of cardiovascular disease.

Comparison of FDG-PET and dynamic contrast-enhanced MRI in the evaluation of suggestive breast lesions.

The aim of our study was a direct comparison of the ability of positron-emission tomography with FDG-PET and of magnetic resonance imaging (MRI) to determine whether breast lesions were benign or malignant and of the two imaging methods capability of depicting eventual multifocal disease. We performed both PET and MRI in 36 patients (40 lesions) who were scheduled for surgery because of suggestive mammographic, sonographic and/or clinical findings. A final histological classification was available for all lesions. Tumour size ranged from 5 to 45 mm (mean 16.7 mm). Sensitivity for lesions, sensitivity for patients, specificity for lesions and specificity for patients were 68.0%, 76.2%, 73.3%, and 73.3% for PET and 92.0%, 95.2%, 73.3%, and 73.3% for MRI, respectively. MRI was more sensitive than FDG-PET in disclosing malignant breast tumours and was also more accurate than FDG-PET in the assessment of multifocal disease. The lower sensitivity of FDG-PET than of MRI seems to be due to difficulties in reliable imaging of carcinomas smaller than 10 mm and of lobular carcinomas.

Bone metabolism in patients with differentiated thyroid carcinoma receiving suppressive levothyroxine treatment.

AIM: Patients with differentiated thyroid carcinoma (DTC) must receive suppressive levothyroxine (LT(4)) therapy for the rest of their lives. The literature, however, presents conflicting results on how this affects bone metabolism. The aim of this study was to assess the influence of the estrogen status and LT(4) therapy, in particular LT(4) dosage in micrograms per kilograms (microg/kg), on bone metabolism in female patients with DTC. MATERIAL AND METHODS: Three markers of bone metabolism (C-terminal telopeptide of type I collagen in serum [SCTx]; N-terminal telopeptide of type I collagen in urine [U-NTx]; and osteocalcin [OC]) were investigated in four groups: group REF (healthy premenopausal female controls), group DTC-ES (premenopausal women with DTC and normal estrogen levels), group DTC-ED (postmenopausal women with DTC and estrogen deficiency), and group DTC-HRT (postmenopausal women with DTC undergoing hormone replacement therapy [HRT]). All patients with DTC were on a well-adjusted suppressive LT(4) therapy with TSH levels 0.1 mU/L or less. RESULTS: In group DTC-ES bone turnover was comparable to group REF, whereas in group DTC-ED, all three markers were significantly increased as compared to groups REF and DTC-ES. In group DTC-HRT, the HRT normalized U-NTx and OC. However, in this group S-CTx was not completely normalized by HRT in all patients, although also significantly lowered compared to group DTC-ED. The analysis of LT(4 )dosage per kilogram showed that premenopausal DTC-patients had increased markers of bone metabolism if LT(4) dosage exceeded 2.6 microg/kg. Estrogen-deficient patients with DTC, however, had a much lower critical LT(4) dosage, above which increased markers of bone metabolism were seen. CONCLUSION: A well-adjusted suppressive LT(4) therapy of less than 2.6 microg/kg and normal estrogen levels do not seem to increase bone metabolism in estrogen-sufficient patients with DTC. The normalization of an estrogen deficiency by HRT or other antiresorptive therapies and minimal suppressive dosages of LT(4) are attempts to optimize the care of patients with DTC. In postmenopausal patients with DTC and patients with DTC who require LT(4) dosages in excess of 2.6 microg/kg, the information provided by markers of bone metabolism may help to prevent bone damage.

Accuracy of whole-body 18F-FDP-PET for restaging malignant lymphoma.

BACKGROUND: The aim of this retrospective study was to evaluate the accuracy of fluorine-18 fluorodeoxyglucose positron emission tomography (18F-FDG-PET) images, which were interpreted under daily routine conditions, in patients with Hodgkin's disease (HD) or non-Hodgkin lymphoma (NHL) for restaging after chemotherapy and/or radiotherapy. For this purpose, 18F-FDG-PET results were compared with morphological imaging methods and the patients' clinical background. METHODS: 121 PET images of 93 lymphoma patients (44 HD, 49 NHL) were investigated after chemotherapy/radiotherapy. For PET imaging, 160-200 MBq 18F-FDG was administered intravenously, followed by an infusion of 20 mg Furosemid in 250 mL saline. Whole-body 18F-FDG-PET images were obtained using a partial-ring PET scanner without attenuation correction. The morphological imaging consisted in computed tomography and ultrasound (CT/US) in all patients, additional MRI in some patients, and iliac crest biopsy in cases of suspicious bone marrow involvement. The standard of reference was composed of biopsy data, clinical status at the time of investigation, and follow-up of at least 12 months. The PET images were evaluated for their sensitivity, specificity and accuracy based on written reports, which were compiled from other imaging data and the clinical history of the patients. RESULTS: Sensitivity, specificity, and accuracy of 18F-FDG-PET was 91 %, 81 %, and 85 %; of CT/US, 88 %, 35 %, 56 %, respectively. Major sources of error in 18F-FDG-PET were due to asymmetric muscular hypermetabolism and inflammatory lesions misinterpreted as persistent viable lymphoma tissue. Furthermore, secondary malignancies other than lymphomas were another reason for misinterpretations of 18F-FDG-PET studies. CONCLUSIONS: 18F-FDG-PET showed a comparable sensitivity but a higher specificity and accuracy compared with CT/US. To achieve a high accuracy in 18F-FDG-PET, the nuclear medicine specialist needs imaging and clinical data as background information, which can only be acquired through close co-operation with the referring clinicians. Pharmacological muscular relaxation in the course of 18F-FDG-PET imaging may be advisable, as nonspecific muscular hypermetabolism was one of the problems at the image readings and a source of incorrect 18F-FDG-PET interpretations.

Iodine supplementation in Austria: methods and results.

Until 1963 Austria was an extremely iodine-deficient area with low iodine intake and high goiter prevalence. Therefore, for the first time in 1963, salt iodination with 10 mg of potassium iodide per kilogram of salt was introduced by federal law. Twenty years after this salt iodination, however, investigations in schoolchildren demonstrated iodine deficiency grade I to II according to the World Health Organization (WHO) (urinary iodine excretion, 42-75 microg/g Crea) and goiter prevalence of far more than 10%. In 1990, salt iodination was increased to 20 mg of potassium iodide per kilogram of salt. In 1994, further investigations in schoolchildren demonstrated an increase of urinary iodine excretion (121 microg/g Crea) and a reduction of goiter prevalence below 5%, with the exception of pupils ages 14-19 (12%). In the year 2000, 10 years after the increase of salt iodination in Austria, 430 nonselected adult inhabitants of three communities in Carinthia (a county of Austria) were investigated for iodine excretion, goiter prevalence, and prevalence of thyroid autoantibodies. This study demonstrated that although iodine supply is sufficient now in Austria (males, 163.7 microg of Crea; females, 183.3 microg of iodine per gram of Crea), goiter prevalence is still high in the elderly, who lived for a longer period of iodine deficiency (34.3% in women and 21.3% in men), whereas goiter prevalence in younger people up to age 40 years is below 5%. It could also be shown that the percentage of thyroid autoantibodies is now as high as in other countries with sufficient iodine supply (3.19% in males, 5.17% in females). In addition to the changes of urinary iodine excretion and goiter prevalence because of salt iodination, changes of incidence in hyperthyroidism and histologic types of thyroid cancer are discussed in this paper. In conclusion, the introduction of salt iodination led to an improvement in iodine supply with a marked reduction of goiter prevalence in people who were born after 1963, but also to an increase in hyperthyroidism and autoimmune thyroid diseases as well as changes in histologic types of thyroid cancer.

(18)F-FDG positron emission tomography in the early diagnosis of enterocolitis: preliminary results.

Collagenous and eosinophilic colitis are rare diseases characterised by chronic watery diarrhoea. Radiographic evaluation of the gastrointestinal tract and colonoscopy are usually non-diagnostic since as many as one-third of patients will have minor abnormalities. To date a few investigators have reported increased fluorine-18 fluorodeoxyglucose ((18)F-FDG) uptake on positron emission tomography (PET) in patients with acute enterocolitis, but there have been no reports on the use of (18)F-FDG PET for the diagnosis of collagenous or eosinophilic colitis in an early clinical stage. The aim of this preliminary study was to evaluate the usefulness of (18)F-FDG PET in the early diagnosis of patients with colitis. We investigated five women (mean age 61.2+/-12.1 years) who had been diagnosed as having colitis in an early clinical stage. In all but one of the patients, the diagnosis of colitis was based on biopsy. Magnetic resonance colonography, ultrasonography and colonoscopy were performed in all but one of the patients. Two women were identified as having collagenous colitis in an early clinical stage. Another two patients had eosinophilic colitis. The morphological imaging methods, magnetic resonance colonography and ultrasonography, yielded no suspicious findings, and the results of colonoscopy similarly showed no abnormalities. One patient had colitis due to bacterial infection. In all patients (18)F-FDG PET showed a pathological increase in tracer uptake in the large bowel, suggestive of colitis. In four of the five patients, colitis was confirmed by histology, and in one, by bacterial analysis. (18)F-FDG PET was able to detect colitis in an early clinical stage, when morphological imaging methods and colonoscopy were non-diagnostic. The early performance of (18)F-FDG PET imaging in patients with possible colitis is encouraging.

[F-18 fluorodeoxyglucose positron emission tomography in malignant lymphoma]. / F-18-Fluorodeoxy-Glukose-Positronenemissionstomographie bei malignen Lymphomen.

Non-invasive imaging methods are important diagnostic tools for initial staging and re-staging after radiochemotherapy in patients with malignant lymphomas. Conventional imaging is mainly based on CT although MRI and sonography also gain more and more importance in these indications. The F-18-Fluorodeoxyglucose-positron emission tomography (F-18-FDG-PET) imaging is based upon increased glucose metabolism in tumor tissue, a phenomenon also seen in lymphomas with the exeption of MALT type lymphomas. Comparative studies between conventional imaging methods and F-18-FDG-PET showed that F-18-FDG-PET is capable of visualizing the extent of lymphomas with high sensitivity and specificity at initial staging and at re-staging after therapy. Results of F-18-FDG-PET were better than those of conventional imaging. One of the major limitations of conventional imaging with CT is the lack of distinguishing residual lymphoma tissue and fibrotic scar tissue after therapy. However, F-18-FDG-PET is capable to resolve this problem as it is based on metabolism and it can distinguish with high sensitivity and specificity between residual lymphoma tissue and fibrotic scar tissue after therapy. Thus, in particular, in those patients with residual lymphoma bulks after therapy, the use of F-18-FDG-PET can give essential informations with regard to the planning of further therapeutic interventions. In conclusion, F-18-FDG-PET seems to open new dimensions in imaging of lymphoma both for initial staging and for restaging after therapy. Moreover, studies have shown that the use of F-18-FDG-PET in lymphoma patients is cost effective. Due to this background and the fact that the availability of F-18-FDG will be further facilitated, the F-18-FDG-PET will probably gain increasing importance in the management of patients with lymphomas in the close future.

Clinical outcome of radiosynoviorthesis: a meta-analysis including 2190 treated joints.

A variety of indications for radiosynoviorthesis have been reported in literature, but the clinical outcome differs and depends on the primary disease and the pre-existing degenerative changes. This metaanalysis was carried out to establish groups for radiosynoviorthesis based on clinical outcome with respect to primary disease, clinical stage and the pre-existing degenerative changes. The literature search was carried out using the MEDLINE search term 'radionuclide synovectomy'. Based on reports in the literature we determined groups for radiosynoviorthesis for clinical use. Our literature list comprised 2190 joints that were treated with radiosynoviorthesis. The overall response rate for all treated joints was 72.5+/-17%. The mean improvement rate for the treated joints in rheumatoid arthritis was 66.7+/-15.4%. For osteoarthritis the success rate was 56+/-11%, with better results in case of minimal radiological changes. Radiosynoviorthesis in patients with changes according to Steinbrocker I and II was successful in 72.8+/-12.3%, and in 64+/-17.3%, respectively. Steinbrocker III and IV had a mean success rate of 52.4+/-23.6%. In the case of haemophilia and Willebrand's disease a reduction of joint bleedings and factor usages after radiosynoviorthesis was evident in 91+/-4.3%. In patients with pigmented villonodular synovitis radiosynoviorthesis was successful in 77.3+/-25.3%. It is concluded that radiosynoviorthesis provides better results in rheumatoid arthritis than in osteoarthritis. Minimal or moderate changes according to Steinbrocker stages I and II respond better to radionuclide therapy than do stages III and IV. Deformed or unstable joints might fail treatment and therefore surgical interventions should be considered. Close cooperation with orthopaedists and rheumatologists is necessary to consider radiosynoviorthesis in each patient to ensure optimal medical care.

[Tc-99m ciprofloxacin in clinically selected patients for peripheral osteomyelitis, spondylodiscitis and fever of unknown origin--preliminary results]. / Tc-99m-Ciprofloxacin bei Verdacht auf periphere Osteomyelitis, Spondylodiszitis und Fieber unklarer Genese in einem klinisch selektierten Patientengut--vorläufige Ergebnisse.

AIM: Retrospective evaluation of Tc-99m ciprofloxacin (infection) scintigraphy consecutively performed in a series of patients clinically suspected for peripheral osteomyelitis (OM), spondylodiscitis (SD) and fever of unknown origin (FUO). METHODS: A total of 20 patients clinically suspected for OM (n = 12), SD (n = 3) and FUO (n = 5) were included in our retrospective analysis. The additional criterion was a positive 3-phase bone scan for OM, or a 2-phase bone scan in case of SD. Planar whole body scans and static acquisitions were performed 1 and 4 h after application of 370 MBq Tc-99m ciprofloxacin. In 10 patients with suspected OM, additional immunoscintigraphy using Tc-99m labelled monoclonal antibodies (Mab BW 250/183) was performed and the correlation of infection to bloodpool and antigranulocyte scintigraphy was analysed. RESULTS: OM: Bacterial infection was confirmed in 8 of 15 lesions. Infection demonstrated true positive (TP) results in 7 of 8, true negative (TN) results in 2 of 7, false positive (FP) results in 5 of 7 patients and one false negative (FN) result. A strong correlation could be demonstrated between T/NT ratios of infection and bloodpool Tc-99m medronate imaging (r = 0.84, 0.88) and between infection and BW 250/183 (r = 0.92, 0.90). Using a threshold of 2.0 for T/NT ratio, only TP results could be observed whereas a T/NT in the range of 1.0-2.0 could not discriminate between septic and aseptic inflammation. Concordant results with Mab BW 250/183 could only be observed in 5 of 10 patients (4 TP, 1 TN) by showing 4 FP and 1 FN lesions with IF. CONCLUSION: Non-specific uptake of infection can be observed in a variety of clinical situations with moderate uptake, by showing a strong correlation with blood-pool imaging. Nevertheless, intense uptake may be specific for septic inflammation.