Trends in clinical chemistry

Analytical chemistry and clinical chemistry have come closer together over the past thirty years and increasingly profit from each other. Advances in elucidating the human genome and the genomes of viruses and microorganisms have made it possible to track down a disease to the level of the nucleic a cids and the genetic code, and to identify a disease on the molecular level . Examples are given of the diagnosis of a complex of inherited diseases, t he porphyrias, on a molecular basis and of the identification of a virus in fection referred to as Bordetella Pertussis. In addition, the trend to on-s ite analysis, which can provide immediate information about the state of a patient, is contrasted with high-throughput analysis in central laboratory units. The second contribution deals with the logistics of point-of-care te sting (POCT) and its technological prerequisites in Sweden. In clinical chemistry, novel technologies are not primarily rated according to their originality but rather according to logistic considerations. Thes e include economic factors, the time-elapse to information, the ease of qua lity assessment and the consequences of a positive result, i.e. of a result which exceeds the decision limit separating sick patients from the populat ion of healthy individuals, During the past 30 years, since 1968, the techn ical equipment used in clinical chemistry has been revolutionized and it ha s become much more widespread. Currently major advances are being made in P oint-of-Care Testing (POCT) and Home Care Testing where Laboratory Informat ion Technology (LIMS) and global exchanges via the Ethernet and Internet ha ve become important links in the information chain. Automation has been dri ven forward so that it is now possible to automate the separation steps, th e sample pretreatment and sample distribution steps at high throughput, Whe n performing special analyses where the analytical procedure cannot be impl emented using high-throughput instruments, it has been beneficial to apply advances in analytical chemistry to clinical chemistry. Such advances inclu de analytical techniques such as mass spectrometry, gas chromatography, and HPLC. In some special domains where analytical technologies are applied to provide specific information based on, for example, the separation and ide ntification of peptides and proteins via, for instance, two-dimensional ele ctrophoresis, blotting techniques or PCR-relied analyses, clinical chemistr y is even more advanced than analytical chemistry. However, in clinical che mistry, using an analytical technique is only justified if a positive resul t can lead to a useful medical treatment and to an improvement in the slate of health of the patient. At the same time, the work that aims to describe the entire human genome by the year 2003 [1] has stimulated, and continues to stimulate, practices an d techniques that allow gains in information to be tracked down to the sour ce of a disease. It has also become possible in some cases to predict the p robability of being affected by an 'illness', which is based on a genetic p redisposition, before symptoms break out, This means that prevention can be more effective, so that people liable to be affected by a hereditary disea se can be trained to adjust their everyday behavior and to try to prevent t he illness. In microbiology, it is now possible with PCR and electrophoresi s to identify microorganisms in a timeframe of single days instead of the d ays and weeks needed to cultivate microorganisms. In the following, the authors provide insights into the organization of poi nt-of-care testing (POCT) and describe some specific techniques which shoul d solve some:problems currently facing clinical chemistry.