Aids for Diagnosis

Layered events and recommendations are developed primarily by experienced personnel. For this reason some experienced personnel are always assigned to investigation teams. Inexperienced team members learn from the experienced personnel, and often they also make significant contributions through an open and probing discussion. 

Use the investigation described in Example 12-1 to develop an investigation summary. 

The data collected during an investigation are studied and analyzed to establish the causes of the accident and to develop recommendations to prevent a recurrence. In most cases the evidence clearly supports one or more causes. Sometimes, however, the evidence needs added 

Further searching in this region may reveal possible causes of the fire, as shown in the following discussion. 

The fire temperature for various materials, such as wood, plastic, and solvents, is approximately 1000°C. Because pure copper melts at 1080°C, copper wire usually survives fires. If copper beads are found around electrical equipment, it may indicate that electrical arcs created temperatures greater than those observed in fires. Sometimes pits at the ends of conductors indicate high temperatures and vaporization of copper while arcing. Although this type of evidence indicates a source of ignition, it may not be the primary source of the fire. 

---

As an aid for diagnosis, a PTR-TOF-MS was nsed in the investigation of liver cirrhosis and the severity of the disease was assessed by direct analysis of exhaled breath [88]. Kohl et al. examined the breath of 96 patients shortly before and after kidney transplantation using PTR-MS. They found creatine in urine and breath showed good eortelation [89]. Aprea et al. used a PTR-TOF-MS to investigate metabolites in the exhaled breath of patients affeeted by coeliac disease who were on a gluten free diet [90]. A PTR-TOF-MS was also irsed to calibrate an acetone sensor... 

Allergy mediated by selective IgE to certain types of NSAIDs by which symptoms are caused exclusively by a specific group of NSAIDs and no cross-reactivity exists with the other groups of anti-inflammatories. In a study carried out with 26 methimazole-allergic patients with IgE-mediated reactions [33], 14 of which developed anaphylaxis, BAT showed a sensitivity of 42% with an optimum specificity of 100%. No other validated in vitro test exists to date for the diagnosis of this disorder and so it represents an essential aid to diagnosis. 

In silico models will aid both the standardisation and individualisation of medical care. Standardisation of diagnoses, drug and device descriptions, procedures, etc. will make relevant information more readily and more widely available. On the other hand, advanced models will allow development of patient-specific procedures for diagnosis and treatment. This will move the focus from the treatment of diseases to the curing of patients. 

The varying metabolic activities of bacteria and their response to immediate environmental factors have been exploited in the design of special diagnostic and selective media. Recipes for these run into many hundreds such media are used in hospital and public health laboratories for identifying organisms found in samples believed to be contaminated by them, and as an aid to diagnosis and treatment. In addition they are used to detect contaminants in pharmaceutical products (British Pharmacopoeia 1993). A few examples will be given to illustrate the principle. 

Diagnosis of acute pancreatitis is based on the patient s history and presenting signs and symptoms. Evaluation of laboratory results, specifically the serum amylase and lipase, aids in diagnosis. Serum amylase is elevated early in the disease process but may return to normal within 12 hours.10 Serum lipase will remain elevated for days after the acute event and may lend itself more to the diagnosis depending on when the patient presents for evaluation.11... 

Probably the most effective use of XRF and TXRF continues to be in the analysis of samples of biological origin. For instance, TXRF has been used without a significant amount of sample preparation to determine the metal cofactors in enzyme complexes [86]. The protein content in a number of enzymes has been deduced through a TXRF of the sulfur content of the component methionine and cysteine [87]. It was found that for enzymes with low molecular weights and minor amounts of buffer components that a reliable determination of sulfur was possible. In other works, TXRF was used to determine trace elements in serum and homogenized brain samples [88], selenium and other trace elements in serum and urine [89], lead in whole human blood [90], and the Zn/Cu ratio in serum as a means to aid cancer diagnosis [91]. 

For example, ISOLABS, Inc. has a test used to detect IgG in cerebral spinal fluid as an indicator of infection. If no neurological disease exists the concentration of IgG is less than 10% of all CSF proteins. Should multiple sclerosis be present the [IgG] will range from 11-35%. This result plus the results of other confirmatory tests can significantly aid in diagnosis. 

Q2 There is a wide range of respiratory function tests available many can be performed using spirometry or simple equipment such as the peak flow meter. The tests are used to aid the diagnosis of the respiratory disorder present, to follow the course of the disease, which may be recurrent or progressive, and to monitor the effects of therapy. In addition, there are specific occupational lung diseases, for which patients who have a respiratory disability, because of adverse conditions at the workplace, may claim some financial compensation. Their compensation depends on the extent of their respiratory disability. 

The activity is found in erythrocytes, platelets, and lymphocytes, and determination of its value aids in diagnosis of some blood disorders. In this assay, which can readily be used for purine and pyrimidine 5 - and 3 -nucleotidase activities, the nucleoside monophosphate (the substrate) was separated from the nucleoside (the product) using ion-pair reversed-phase HPLC with a mobile phase of 5% methanol-5 mAf potassium dihydrogen phosphate 0.25 mAf 1-decanesulfonic acid was also added to the mobile phase. The elution was carried out at room temperature and the eluent monitored at 254 nm. 

Activation analysis can be used for determination of trace elements, in particular heavy metals and essential elements, in various parts or organs, respectively, of plants or animals and man. Making use of the high sensitivity of activation analysis, small samples of the order of several milligrams taken from selected places give information about the concentration of the elements of interest. The results of activation analysis of trace elements also allow conclusions with respect to diseases or malfunctions and are valuable aids to diagnosis. Examples are the determination of Se in man or of trace element concentrations in bones or other parts, with respect to the sufficient supply of essential elements and metabolism. In vivo irradiation has also been proposed. 

Enzymes, which are normally produced in cells, are released into the blood when cells are injured. For example, after a heart attack, there is an increase in blood levels of creatine phosphokinase (CPK) and other enzymes such as lactate dehydrogenase (LDH). The extent of damage and the rate of recovery can be estimated by periodically measuring the levels of these enzymes. Measurement of the MB isozyme of CPK is also used as an aid in diagnosis. 

GA 125 as an aid in diagnosis, for monitoring treatment, and early prediction of recurrence... 

Vargo JS, Becker DM, Philbrick JT, Schoonover FW, Davis JS. Plasma DNA. A simple, rapid test for aiding the diagnosis of pulmonary embolism. Chest 1990 97 63-8. 

---