The diagnostic accuracy of temporal artery ultrasound and temporal artery biopsy in giant cell arteritis: A single center Australian experience over 10 years.

AIM: To assess the diagnostic accuracy of temporal artery ultrasound compared with temporal artery biopsy and clinical diagnosis in patients with suspected giant cell arteritis (GCA) over 10 years in an Australian center. METHOD: Patients presenting to Westmead Hospital with possible GCA from March 2011 to December 2020 were retrospectively identified. The following parameters were obtained from the medical record: clinical presentation, inflammatory markers, temporal artery ultrasound findings, and temporal artery biopsy report. Data were assembled in a 2 × 2 table; sensitivity and specificity of temporal artery ultrasound compared with temporal artery biopsy and clinical diagnosis were calculated. RESULTS: Over the 10-year study period, 65 temporal artery ultrasounds were performed in 63 patients (n = 65; 61.9% female) with a mean ± standard deviation age of 69.6 ± 12.3 years. Thirteen out of 65 (20%) temporal artery ultrasounds had findings suggestive of GCA. Twenty patients (31.7%) had a clinical diagnosis of GCA irrespective of sonographic or biopsy findings. Compared with temporal artery biopsy, temporal artery ultrasound had a sensitivity of 71.4% and specificity of 93.3%. Compared with clinical diagnosis made by the treating rheumatologist, temporal artery ultrasound had a sensitivity of 55% and specificity of 95.3%. CONCLUSION: Temporal artery ultrasound is a useful non-invasive investigation in the assessment of suspected GCA. If positive in the setting of a suggestive clinical presentation, a temporal artery ultrasound probably avoids the need for a temporal artery biopsy. Temporal artery ultrasound could be more widely used in the clinical management of GCA.

Evaluating disease activity in patients with ankylosing spondylitis and rheumatoid arthritis using 99mtc-glucosamine.

OBJECTIVE: To evaluate the clinical utility of a novel radiotracer, 99mTc-glucosamine, in assessing disease activity of both rheumatoid arthritis (RA) and ankylosing spondylitis (AS). Material and Methods: Twenty-five patients with RA (nine males and 16 females) and 12 patients with AS (all male) at various stages of disease were recruited for the study. A clinical history and examination was performed, followed by the measurement of hematological, biochemical, and autoimmune serological parameters to assess disease activity. 99mTc-glucosamine was intravenously administered and scans were compared with other imaging modalities, including plain X-ray, magnetic resonance imaging (MRI), and bone scans. RESULTS: In patients with AS, 99mTc-glucosamine scans were more capable of identifying active disease and differentiating between inflammatory and non-inflammatory causes. In patients with RA, 99mTc-glucosamine accumulated at all known sites of disease involvement. Uptake was most pronounced in patients with active untreated disease. The relative tracer activity in the involved joints increased with time compared with that in the adjoining soft tissue, liver, and cardiac blood pool. Using Spearman's correlation coefficient, there was a positive correlation among glucosamine scan scores, C-reactive protein (p=0.048), and clinical assessment (p=0.003), which was not noted with bone scans. CONCLUSION: The radiotracer was well tolerated by all patients, with no adverse reactions. 99mTc-glucosamine imaging could detect spinal inflammation in AS. With respect to RA, 99mTc-glucosamine was a viable alternative to 99mTc-labeled methylene diphosphonate nuclear bone scans for imaging inflamed joints and had the added advantage of demonstrating a significant clinical correlation between disease activity and scan findings.

The role of 99mTc-labelled glucosamine (99mTc-ECDG) in the evaluation of rheumatic joint disease: a screening experience.

OBJECTIVES: We investigated the localization pattern of a novel imaging agent, (99m)Tc-labelled glucosamine (ECDG), in a variety of rheumatic conditions. MATERIALS AND METHODS: Sixteen patients were recruited into the study, with either active rheumatoid arthritis or osteoarthritis. (99m)Tc-ECDG was prepared in-house and patients received 400 MBq intravenously; thereafter, static images were acquired 15 min, 2 h and 4 h later, using a dual-head Siemens e-cam. Images were interpreted by an experienced physician for (a) accumulation of tracer at sites of known disease; (b) relative activity over time; (c) detection of subclinical disease; (d) detection of unrelated disease; and (e) distribution of tracer at involved joints. RESULTS: Optimal images were obtained by 2 h after injection in all patients. (99m)Tc-ECDG accumulated at all clinically known sites of disease. Uptake was most pronounced in the patients with active but untreated disease. Relative tracer activity at involved joints increased with time when compared with activity in the adjoining soft tissue, liver and cardiac blood pool. Focal uptake was seen with local pathology such as supraspinatus tendinitis. Tracer uptake correlated well with disease severity, and insignificant tracer accumulation was evident at sites with no documented disease. Tracer distribution in joints appeared to conform predominantly to the synovium in patients with rheumatoid arthritis, whereas it was articular in patients with degenerative joint disease. CONCLUSION: (99m)Tc-ECDG accumulates at sites of active rheumatic disease and is able to differentiate between synovial and bone uptake. This agent may have a role in the assessment and monitoring of rheumatic conditions.

Torsion of intraperitoneal kidney transplant.

BACKGROUND: Torsion of kidney transplant refers to rotation of the kidney transplant graft around its vascular pedicle resulting in vascular compromise and infarction. It is a rare complication of kidney transplantation associated with a high rate of graft loss. Clinical presentation and diagnostic imaging modalities are non-specific, and surgical exploration is therefore often delayed. METHODS: We present a case report and review of the literature. Studies were identified by searching Medline and Embase from January 1954 to December 2010. Data was extracted regarding the clinical presentation, investigation, findings on surgical exploration, and treatment outcomes of patients with torsion of kidney transplant. RESULTS: Eight manuscripts with 16 cases of kidney torsion were found. Presenting symptoms were decreased renal function (13 cases), abdominal pain (10 cases), oliguria/anuria (9 cases), nausea and vomiting (4 cases), fever (3 cases), diarrhoea (3 cases), weight gain (2 cases), oedema (3 cases), fatigue (1 case) and impalpable graft (1 case). Investigations were Doppler sonography (11 cases), grey-scale sonography (7 cases), nuclear scintigraphy (5 cases), computed tomography scan (4 cases), and magnetic resonance imaging/magnetic resonance angiography (1 case). Of the 16 published cases of torsion, seven (44%) grafts were detorted and salvaged, three (19%) grafts were detorted but subsequently lost and six (38%) patients underwent immediate nephrectomy. CONCLUSIONS: A prompt consideration of the diagnosis of torsion of kidney transplant is required to prevent delay in surgical intervention. We recommend urgent Doppler ultrasound be used as first-line investigation, followed by prompt surgical exploration. We recommend the use of prophylactic nephropexy to prevent torsion.

(68)Ga-Citrate-PET for diagnostic imaging of infection in rats and for intra-abdominal infection in a patient.

OBJECTIVES: 67Ga-Citrate has been extensively used for infection and inflammation imaging for the past four decades but has limitations. In the present study, we explored the ability of 68Ga-Citrate to detect Staphylococcus aureus (Staph A) infection in rats and further studied its ability to localize intra-abdominal infection in a patient. METHODS: An infection was induced in male Wistar rats by injecting Staph A in the right thigh muscle. In this study a simple method was described for the preparation of 68Ga-Citrate with > 99% yield and purity. 68Ga-Citrate (15 MBq/rat and 150 MBq/patient) was injected intravenously and the images were acquired for 10 min each. RESULTS: 68Ga-Citrate uptake was moderate at the infection lesion within 5 min post injection but intense focal uptake was visualized from 30 min to 6 hr post-injection in rats. Cardiac blood pool and liver activity decreased during the same period of study. In the patient studied, an infected area in the abdomen at the site of recent appendectomy was detected within 30min post-injection of 68Ga-Citrate, which was consistent with CT and microbiology findings. CONCLUSION: A simple method of preparation of 68Ga-Citrate with > 99% yield and purity was described, suitable for routine clinical work. Our results showed 68Ga-Citrate is capable of detecting Staph A infection in rats and an intraabdominal infection in a post-operative patient. These findings indicate the high potential of 68Ga-Citrate for clinical utility.

Successful resection of localized intestinal lymphangiectasia post-Fontan: role of (99m)technetium-dextran scintigraphy.

Intestinal lymphangiectasia is a well-recognized complication of the Fontan procedure, occurring in up to 24% of patients. Because of the loss of chylous fluid into the gut lumen, protein-losing enteropathy results as well as lymphopenia and hypogammaglobulinaemia. In some cases, dilated lymphatics in the intestinal serosa or mesentery also rupture, causing chylous ascites. Standard medical and cardiac surgical interventions are generally ineffective and the condition is frequently lethal. We report a case of intractable and life-threatening chylous ascites and chylothorax in a 14-year-old girl, associated with intestinal lymphangiectasia and protein-losing enteropathy after a Fontan procedure for tricuspid atresia. The condition was refractory to all standard medical therapies, including dietary modifications, diuretics, corticosteroid therapy, albumin infusions, octreotide, heparin, bowel rest, and parenteral nutrition. Cardiac surgery to optimize her hemodynamic status was also ineffective and large volume pleural and ascitic fluid losses continued. Having exhausted all other therapeutic modalities, (99m)technetium-dextran scintigraphy was performed to assess the extent of intestinal protein loss and the potential for surgical intervention. Scintigraphy suggested localized protein loss from the proximal jejunum and subsequent segmental resection was effective. Postoperatively, ascites and pleural effusions resolved, and there was no evidence of short bowel syndrome. Growth has accelerated and the patient has entered puberty. There is mild persistent intestinal protein loss requiring diuretic therapy. Ascites or pleural effusions are absent, and the patient remains well >2 years after surgery. Intestinal lymphangiectasia post-Fontan procedures has traditionally been ascribed to hemodynamic factors such as raised systemic venous pressure, which would predispose to a generalized intestinal lesion. However, in this case, scintigraphy demonstrated a localized, surgically correctible lesion. To our knowledge, this is the first reported case of the use of (99m)technetium-dextran scintigraphy for this indication and of successful partial small bowel resection in such a case.

Abnormal uptake of Technetium-99 m hydroxymethylene diphosphonate in the liver.

Diffuse liver uptake on bone scintigraphy is a rare occurrence with only a few reports in the literature. A case of diffusely increased uptake in a patient with acute hepatitis is presented.

Extrarenal uptake of 99mTc-DTPA at the site of bone marrow biopsy.

Unexpected iliac uptake of 99mTc-DTPA was noted in a 10-year old female referred for evaluation of renal function prior to receiving chemotherapy for relapsed acute lymphocytic leukemia. This scan finding corresponded to the site of a bone marrow biopsy performed five days earlier. X-ray of the area revealed no abnormality. It is assumed that the extrarenal uptake was due to increased vascularity at the site of recent bone marrow biopsy, most likely due to increased osteoblastic reaction in the cortex of the ilium. The patient proceeded with the bone marrow transplant and was well at follow-up six months later.