INTERPRETIVE REPORTING OF PROTEIN ELECTROPHORESIS DATA BY MICROCOMPUTER Thomas S. Talamo, M.D., Frank J. Losos, III, MT(ASCP), G. Frederick Kessler, M.D. Department of Pathology, IMontefiore Hospital and the University Health (Center of Pittsburgh, Pittsburgh, Pennsylvani a ABSTRACT microcomputer is currently interfaced with a SOROC IQ-120 cathode ray tube (CRT) for visual display, A microcomputer based system for interpretive programming and inputting of patient data, and a reporting of protein electrophoretic data has been DEC (Digital Equipment Corporation) LA-120 dot ma- developed. Data for serum, urine and cerebro- trix printer. The Monitor disc operating system spinal fluid protein electrophoreses as well as (version 5.0) and North Star extended disc basic immunoelectrophoresis can be entered. Patient were provided by the manufacturer. The entire demographic information is entered through the program package is written in BASIC and is adapt- keyboard followed by manual entry of total and able to other computer systems with similar hard- fractionated protein levels obtained after densi- ware employing BASIC as the programmable language. tometer scanning of the electrophoretic strip. The patterns are then coded, interpreted, and Serum, urine and cerebrospinal fluid electro- final reports generated. In most cases inter- phoreses were performed using an agarose gel sys- pretation time is less than one second. Misinter- tem (Pol-E-Film R). The strips were scanned with a pretation by computer is uncommon and can be Beckman model CDS-200 densitometer after electro- corrected by edit functions within the system. phoresis for 45 minutes in 0.05 molar sodium bar- These discrepancies between computer and path- bitol buffer and stained with Anido Black. Urine ologist interpretation are automatically stored in and CSF specimens were concentrated prior to ap- a data file for later review and possible program pl ication. Immunoelectrophoreses were performed modification. Any or all previous tests on a using the Immunoelectrofilm kit and were read patient may be reviewed with graphic display of manually. the electrophoretic pattern. The system has been in use for several months and is presently well RESULTS accepted by both laboratory and clinical staff. It also allows rapid storage, retrieval and anal- Demographic data, clinical diagnosis, and test ysis of protein electrophoretic data. results for serum, urine and CSF protein electro- phoreses are entered through the keyborad with guidance from the CRT display. The computer assigns a number to each of the major protein INTRODUCTION fractions after comparison with normal range val- ues which are documented within the program. A Interpretive reporting of protein electro- zero is assigned if the particular value is within phoretic data has been confined to serum analysis, the normal range. If increased, a 2 is assigned, and has been performed mainly with the use of and if decreased, a 1 is assigned to the value. A large computer systems (2,7,8) . The microcompu- 5-digit code identifying the protein pattern is ter, with its small size, ease of programming, and generated and a search is made for a matching code rapid data retrieval, is suited ideally for inter- previously programmed into a separate data file. pretive reporting of test batteries when a' large Corresponding English text statements are then number of diagnostic possibilities exist. We have displayed on the CRT for verification by the user. developed a comprehensive microcomputer based sys- If no match is found, the computer lists only the tem for the interpretation and reporting of pro- abnormalities within the pattern (i.e. decreased tein electrophoretic data as well as storage and albumin) along with a statement indicating the retrieval of immunoelectrophoretic data (12). need for clinical correlation. After verification the data is written onto the patient data files MATERIALS AND METHODS and the system is ready to accept another entry. Upon completion of the daily workload, the com- Our hardware consists of a North Star Horizon puter prints all test data with a graphic display II Microcomputer containing a ZILOG Z80-A as the of the test results as well as the interpretation central processing unit with 48k bytes of random of the protein pattern. A summary worklist con- access memory. Two Shugart SA400 minifloppy disc taining an assigned electrophoresis number and drives are utilized, with approximately 180k bytes pertinent demographic data is submitted to the of storage per drive using single-sided double pathologist along with the reports. density 5 1/4 inch hard sectored diskettes. The 759 The English text statements contain the most results can be entered, stored, reviewed and anal- likely conditions associated with a given protein yzed in the same fashion as other protein electro- pattern. The use of the 5-digit code allows 243 phoretic data. possible combinations for protein patterns. Of these, we determined that 55 held enough diag- DISCUSSION nostic significance to warrant a specific inter- pretation. Each code and its interpretation were Computer assisted analysis of electrophoretic then incorporated into linked data files. For the patterns previously involved calculation of a quan- remaining 188 codes, no specific diagnostic state- titative value for each protein region (10,15) or ment could be made, and computer interpretation analysis of strips to create a higher resolution of consists only of the protein abnormalities the proteins present (11,13). Efforts directed present. In addition, accessory programs allow toward interpretation of electrophoretic data have both initial and future programming of each data been few (2,7,8) and usually accomplished with ex- file with new interpretations or codes as needed. pensive computer systems. Interpretive reporting of laboratory data is gaining momentum (6,9) and While this 5-digit coding system works well for similar computer assisted systems exist for thyroid serum protein electrophoresis, urine and CSF function tests (4), assessment of anemia (14), and result interpretation is more difficult. Urine diseases of the liver and biliary tree (3). However protei n el ectrophoreses are most often performed several differences exist between our system and for the detection of monoclonal proteins, by vary- those previously described. ing degrees of proteinuria, which may be tubular or glomerular in origin, can be evaluated and Pribor (7) developed an on-line interpretive interpreted by pattern recognition. Review of 300 algorithm for serum protein electrophoresis using a urine protein electrophoreses enable the calcu- 6-digit coding system. Interpretation consists of lation of ratios of specific protein components various disorders in which the particular protein for each type of proteinuria, and these were incor- pattern has been seen. Our system, while providing porated into the main program. For example, sel- an interpretive statement containing the most like- ective glomerular proteinuria shows mainly albumin ly diagnosis, also stores data permanently with and transferrin in urine (1). These two fractions graphic display capabiltiy, and also handles urine, were always greater than 60% of the total urine CSF and imnunoelectrophoretic data. protein in our reviewed cases of this abnormality. The urine protein electrophoretic interpretation Dito (2) developed a somewhat more complex octal consists of a statement regarding the degree of algorithm for pattern coding and interpretive re- proteinuria (minimal, moderate, severe), the most porting of serum protein electrophoretic data. Dis- likely origin of the proteinuria, and whether or eases and conditions associated with 7-digit codes not a monoclonal protein is present. We did not derived from the five major protein fractions, encounter significant overlap between ratios total protein, and total globulin levels are defining the various protein patterns. entered into a large matrix. A matrix search for the encoded pattern results in interpretation Cerebrospinal fluid protein electrophoreses containing many diagnoses and conditions which are reports consist only of the gamma globulin/total often unrelated to one another. We have decided protein ratio and statements concerning the pres- that the generation of long lists of diganoses de- ence of an oligoclonal pattern. If the gamma glo- creases the value of the interpretation for the bulin percentage is elevated, the computer will clinician. By limit'ipg the length of the code to 5 ask whether or not an oligoclonal pattern is pre- digits, only 243 (3') codes exist for use in data sent. Interpretive comments are then printed on files, making interpretation quick, efficient and the final report following the demographic data, accurate. Although earlier systems are ingenious test results, and graphic interpretation. and provide a large list of diagnostic possibili- ties, acceptance by physicians has been less than However, proper interpretation of protein elec- optimal (5). Criticism has centered around the trophoretic data requires user recognition of cer- medico-legal implications of laboratory documents tain protein abnormalities, such as low level containing lists of diganoses which may be monoclonal proteins or polyclonal hypergammaglob- clinically irrelevant and incomplete and has led to ulinemia. Since 15 proteins can be resolved with rejection of interpretive reports (5). We have cho- agarose gel electrophoresis, there is inherent sen the middle ground of providing the