Sensitive and quantitative, 10-min immunofluorometric assay for D-Dimer in whole blood

INTRODUCTION: Normal concentrations of D-Dimer can be used to exclude venous thromboembolism (VTE). However, methods for sensitive and quantitative D-Dimer measurements at the point-of-care (POC) are still limited. MATERIALS AND METHODS: We developed a 10-min, non-competitive immunofluorometric assay for D-Dimer in citrated whole blood and plasma using pre-dispensed reagents dried in single assay wells. The simple, automated assay procedure comprises a 1:50 sample dilution, one-step incubation, washing, and time-resolved fluorometric measurement directly from the wet well surface. RESULTS: The limits of detection (background + 3SD) and quantification (CV <15%) were 0.05 and 0.2 mg/L D-Dimer, respectively, and the assay was linear up to 400 mg/L. Correlations to Roche TinaQuant (r=0.726, n=200) and Biopool Auto.Dimer (r=0.190, n=149) were carried out using citrated plasma. Diagnostic sensitivity, specificity, and negative (NPV) and positive (PPV) predictive values were 98.7%, 64.4%, 99.1% and 55.1%, and 92.2%, 81.0%, 95.9% and 68.3%, respectively, using cut-off values of 0.6 and 1.0 mg/L, respectively, in outpatients with deep vein thrombosis (DVT) and/or pulmonary embolism (PE) (n=77) compared with outpatients with various other diseases (n=174). The within- and between-run CVs near the cut-off values were < or =10% in both whole blood and plasma. The 95th percentile upper range in apparently healthy individuals was 0.68 mg/L of whole blood (n=101). CONCLUSIONS: The high sensitivity and NPV suggest that the rapid immunofluorometric assay could be valuable for rapid exclusion of VTE in outpatients. With appropriate cut-offs, the assay could potentially be used as a stand-alone test or combined with clinical probability assessment, but further studies are required.     

Diagnosis and treatment of spontaneous aorto-caval fistula

The diagnostic features and operative results of six patients with spontaneous aorto-caval fistula associated with abdominal aortic aneurysm were analyzed. Abdominal pain, pulsatile abdominal mass and haematuria were constant preoperative findings in all patients. Radiological signs of congestive heart failure of various degrees were present in five, abdominal bruit in four and preoperative renal failure in three patients. As preoperative diagnostic examinations i.v. pyelography was done in two patients and ultrasound scanning and angiography of the abdominal aorta in a further two patients. In one ultrasound scanning a dilated inferior vena cava and hepatic veins were seen as an indirect sign of ACF, while in both angiograms the ACF was seen. In these two cases the diagnosis of ACF was made preoperatively, while in four other cases the diagnosis was made during the operation. Three patients survived the operation and were still alive after eight months, four years and six years respectively. Postoperative complications developed in two patients: postoperative ileus in one and deep venous thrombosis and pneumonia in another. Because of its rarity aorto-caval fistula is difficult to diagnose. The presence of haematuria in a patient suffering from abdominal aortic aneurysm should strongly suggest the diagnosis of an aorto-caval fistula.     

Perioperative myocardial infarction in coronary bypass surgery

Thirteen of 199 consecutive patients undergoing coronary artery bypass surgery revealed definite perioperative myocardial infarction (PMI) in electrocardiography (ECG). The occurrence of PMI was not higher in the group of 44 patients who had intermittent aortic cross-clamping than in those patients treated with cold chemical cardioplegia. In 83 patients serum MB isoenzyme of creatine kinase (CK) and LD1 isoenzyme of lactic dehydrogenase were determined. Patients with unchanged ECG had peak CK-MB levels of 0 to 49 U/l (mean 18.7 U/l +/- 2.6 SEM) at 18 hours postoperatively while patients with PMI showed CK-MB levels of 64-350 U/l (mean 207 +/- 53 U/l); the difference was significant (p less than 0.01). In patients with unchanged ECG, LD1 was 139 +/- 19 U/l and 594 +/- 95 U/l in those with PMI (p less than 0.01). Risk factors for PMI were: age greater than or equal to 60 years, coronary endarterectomies, or cardiopulmonary bypass time greater than or equal to 100 minutes. One patient died of PMI while the remaining patients had postoperative courses comparable to those patients without PMI.     

INTRAHEPATIC CHOLANGIOJEJUNOSTOMY FOR MALIGNANT HILAR BILIARY OBSTRUCTION: APPROACH TO THE LEFT HEPATIC DUCT

Biliary enteric anastomosis for relief of biliary obstruction caused by malignancy at the confluence of the bile ducts can be difficult due to non availability of an adequate length of duct for anastomosis. This paper describes an approach to the left hepatic duct to decompress the biliary tree and its successful application in 11 of 12 patients who presented with malignant hilar obstruction.KEYWORDS: Hepaticojejunostomy, Malignant biliary obstruction     

Report of four cases ofYersinia pseudotuberculosis septicemia and a literature review

Yersinia pseudotuberculosis is a rare cause of disease in humans, the most common manifestation being mesenteric lymphadenitis accompanied by abdominal pain and fever. A septicemic form ofYersinia pseudotuberculosis infection has been reported only rarely. It is usually seen in patients with underlying disorders such as diabetes, hepatic cirrhosis or iron overload. Fifty-four cases of septicemic infection were found in the literature. The earlier published cases are reviewed, and four cases occurring in Finland during the period February to June 1992 are reported.     

Cerebrovascular disease: evaluation with transbrachial intraarterial digital subtraction angiography using a 4-F catheter

Three hundred sixty-one patients underwent intraarterial digital subtraction angiography for definite or probable occlusive vascular disease of the carotid arteries. Examinations were performed with 65-cm-long, 4-F aortic catheters. A transbrachial approach was used. Images were good or excellent in nearly all cases. No postprocedural neurologic deficits or hematomas occurred. Permanent pulse deficit occurred in two patients, and temporary deficit occurred in three patients, an improvement over the frequency found in previous transbrachial series using 6-8-F catheters. While these results establish the efficacy of this technique, they also indicate a possible greater relative safety in men than in women.     

Avian Flu – A Bird's Eye View

Influenza A (H5N1) virus infects a variety of animals, birds and humans. Present ongoing epidemic of this deadly virus in poultry livestock and humans has had major economic and health repercussions. It causes a wide spectrum of clinical features in human beings ranging from mild respiratory tract infection to a fatal pneumonia leading to multi organ system failure. Diagnosis is mainly clinical, aided by lab features like lymphopaenia and non-specific chest X-ray findings. Diagnostic tests are being evolved for rapid and specific diagnosis. Management is mainly symptomatic. Newer and effective antivirals, i.e. amantadine, zanamivir etc are also being tried.Key Words: Avian influenza, Severe acute respitatory syndrome, Influenza A