• Aucun résultat trouvé

Text from the book

Establishing the Diagnosis of Chronic Kidney Disease (CKD)

The most important initial diagnostic step in the evaluation of a patient is elevated serum creatinine that can help to distinguish newly diagnosed CKD from acute or subacute renal failure. “Previous measurements of plasma creatinine concentration are particularly helpful. . .” Normal values

(continued)

(continued)

from recent months suggest that the current renal dysfunction could be more acute, and hence reversible. “In contrast, elevated plasma creatinine concentration in the past suggests that the renal disease represents the progression of a chronic process. Even if there is evidence of chronicity, there is the possibility of a superimposed acute process. . .” If the history suggests multiple systemic manifestations of recent onset (e.g., fever, polyarthritis, and rash) renal insufficiency can be acute process.

Some of the laboratory tests and imaging studies can be helpful. “Evidence of metabolic bone disease with hyperphosphatemia, hypocalcemia, and elevated PTH and bone alkaline phosphatase levels suggests chronicity.

Normochromic, normocytic anemia suggests that the process has been ongoing for some time. The finding of bilaterally reduced kidney size (<8.5 cm in all but the smallest adults) favors CKD.” However, once the CKD is advanced the kidneys are small and scarred.

The above text is extracted from Chap. 280 Chronic Kidney Disease (15, page 2318) that deals with establishing diagnosis. However, some data from previous parts of this chapter may be important for diagnosis (e.g. imaging studies). As we can see there are no probabilities in this text. Because of that some expert has to add it, and the best solution is that the author transforms this text to knowledge base. There is only one disease in this text:chronic kidney diseasethat is a part ofdisorders of the kidney and urinary tract.However,metabolic bone disease(part ofdisorders of bone and mineral metabolism) and normochromic and normocytic anaemia (part of haematology) can be defined as syndromes in this text. There are many findings such as serum creatinine, imaging studies, small and scarred kidneys, hyper-phosphatemia, hypocalcaemia, PTH, bone alkaline phosphatase and kidney size.

Now we can acquire previous data in the knowledge base. Diseases and syndromes are acquired in table ‘Disease’ (Table3.5). Metabolic bone diseases Table 3.5 Table ‘Disease’ for the first example

IDdis Disease Classification Frequency Syndrome

IDdis, identification number of Disease table

Table3.6Table‘Findings’forthefirstexample IDfindFindingDiseaseTypeof dataPropertyValueLow valueHigh valueSensitSpecifPredictText link 100009S-creatinineChronickidney diseaseLaboratoryElevatedfor 6months>150NoneNoneHighHighHigh 100010Renal ultrasoundChronickidney diseaseImagingSmallandscarred kidneysNoneNoneNoneHighHighHigh 100011S-creatinineChronickidney diseaseLaboratoryElevatedlessthan 6months>150NoneNoneHighMediumMedium 100012KidneysizeChronickidney diseaseImagingSmallNoneNoneNoneHighMediumMedium 100013KidneysizeChronickidney diseaseImagingNormalorenlargeNoneNoneNoneLowLowLow 100014S-phosphateChronickidney diseaseLaboratoryElevated>1.7mmol/lNoneNoneLowMediumLow 100015S-calciumChronickidney diseaseLaboratoryDecreased<2.1mmol/lNoneNoneLowLowLow 100016S-PTHChronickidney diseaseLaboratoryElevatedNoneNoneNoneLowLowLow 100017Bonealkaline phosphataseChronickidney diseaseLaboratoryElevatedNoneNoneNoneLowLowLow IDfindidentificationnumberofFindingstable;Sensitsensitivity;Specifspecificity;Predictpredictivevalue

and normochromic and normocytic anaemia are diseases, but here in chronic kidney disease they appear as syndromes. Findings are showed in Table 3.6.

Findings are entered without prefix (hyper or hypo) but properties contains these meaning (elevated or decreased). Kidney size are used two times with properties small andnormal and enlarged. It is also possible to use small kidney size and normal or enlarged kidney sizeas different findings.

This differentiation is necessary because kidney size has different meaning for the diagnosis of chronic kidney failure and as we can see sensitivity, specificity and predictive values are different. Solving this dilemma in style is on editor. Different meanings have to be explained in Thesaurus table (Table 3.7) where hyperpho-sphatemia is explained as elevated S-phosphate.

As we can see from Findings table, diagnosis of chronic kidney disease could be established certainly in two cases: if the kidneys are small and scarred or if S-creatinine is elevated more than 6 months. However, is there some combination of findings that can establish diagnosis certainly? Yes, for example, if we found small kidneys and elevated creatinine for less than 6 months in a person who is not small, then the diagnosis of chronic kidney disease is certain (Table3.8). Another combination that can raise importance is elevated serum creatinine less than 6 months together withmetabolic bone diseaseandnormochromic and normocytic anaemia. If DDSS is connected to information system, sensitivity, specificity and predictive value can be measured.

Consider now retrieval of knowledge base. If somebody wants to know about findings for the chronic kidney disease, then that is very simple. He will find chronic kidney diseaseindisease of kidney and urinary tract. Popup with findings will list findings in chronic kidney disease according to sensitivity, specificity and predictive value so it will be similar to table Findings and will include fields finding + property together with syndromes in chronic kidney disease.

Table 3.7 Table ‘Thesaurus’ for the first example

IDthes MedicalTerm Synonymous

1000003 Hyperphosphatemia Elevated S-phosphate; S-phosphate>1.7 mmol/l 1000004 Hypocalcaemia Decrease S-calcium; S-calcium<2.1 mmol/l IDthesidentification number of Thesaurus table

Table 3.8 Table ‘Relations’ for the first example

IDrel Disease Relation

IDrelidentification number of Relation table;TypeRelationtype of relation;NumberFindnumber of findings;Sensit sensitivity;Specifspecificity;Predictpredictive value; Column ‘Relations’

shows IDfind from Table3.5– Findings or IDdis from Table3.6– Diseases

If query is raised typing the word creatinine, it will list all creatinine findings in all diseases together with properties. If somebody selects elevated creatinine for more than 6 months, diagnosis of chronic kidney disease will appear. If somebody selects elevated creatinine less than 6 months, then findings and properties for chronic kidney disease will appear. However, if somebody selects elevated phosphorus, then some endocrine disease findings will appear in popup. Finding for chronic kidney disease will be at the end of popup. Typing another finding that is specific for kidney diseases will now show another list of findings where kidney disease findings appear first.

Example 2

Text from the book

Confirming the Diagnosis of Acute Rheumatic Fever (ARF)

“Because there is no definitive test, the diagnosis of ARF relies on the presence of a combination of typical clinical features together with evidence of the precipitating group A streptococcal infection. . .” Experts of the World Health Organization clarified the use of the Jones criteria in ARF. These criteria include a preceding streptococcal type A infection as well as some combination of major and minor manifestations.

Table 215 Criteria for diagnosis ARF (simplified) Diagnostic Categories Criteria

Primary episode of Rheumatic fever Two major or one major and two minor manifestations plus evidence of preceding group A streptococcal infection

Rheumatic chorea Other evidence not required Insidious onset of rheumatic

Elevated or rising anti-streptolysin O or other streptococcal antibody, or A positive throat culture, or rapid antigen test for group A streptococcus, or recent scarlet fever

The above text is extracted from Chap. 322 Acute Rheumatic Fever (15, page 2755) that deals with establishing diagnosis. However, some data from previous parts of this chapter may be important for diagnosis. As we can see this is special case were diagnostic criteria are clear and could be easily transformed without expert.

There is only one disease –acute rheumatic fever– but several other diseases are used as syndromes:rheumatic chorea, rheumatic carditis, rheumatic heart disease, carditis, polyarthritis, chorea, erythema marginatum, subcutaneous nodules and scarlet fever.There are next findings:fever, polyarthralgia, erythrocyte sedimenta-tion rate (ESR), leukocyte, P-R interval, anti-streptolysin O (ASTO) and throat culture.

Now we can acquire previous data in the knowledge base. Diseases and syndromes are acquired in table Disease (Table3.9) and findings in table Findings (Table3.10).

Synonymous are acquired in Thesaurus table (Table3.11)

Complex relationship among the findings is showed in table Relations (Table 3.12). Here syndromes are acquired and then relations among findings.

Table 3.9 Table ‘Diseases’ for the second example

IDdis Disease Classification Frequency Syndrome IDdisidentification number of Disease table

Table3.10Table‘Findings’forthesecondexample IDfindFindingDiseaseTypeofdataPropertyValueLow valueHigh valueSensitSpecifPredictText link 100018FeverAcuterheumatic feverExamination>37NoneNoneHighLowLow 100019PolyarthralgiaAcuterheumatic feverSymptomNoneNoneNoneHighLowLow 100020ESRChronickidney diseaseLaboratoryElevated>20NoneNoneHighLowLow 100021leukocyteAcuterheumatic feverLaboratoryElevated>10,000NoneNoneMediumLowLow 100022P-RintervalAcuterheumatic feverECGProlongedNoneNoneNoneLowLowLow 100023ASTOAcuterheumatic feverLaboratoryElevated>200NoneNoneHighMediumMedium 100024ThroatcultureAcuterheumatic feverLaboratoryStreptococcus>100,000/ mlNoneNoneHighMediumMedium IDfindidentificationnumberofFindingstable;Sensitsensitivity;Specifspecificity;Predictpredictivevalue

Table 3.11 Table ‘Thesaurus’ for the second example

IDthes Medical term Synonymous

1000005 ESR Erythrocyte sedimentation rate

1000006 ASTO Anti-streptolysin O

IDthesidentification number of Thesaurus table

Table 3.12 Table ‘Relations’ for the second example

IDrel Disease Relation TypeRelation NumbFind Sensit Specif Predict Text link 10005 Acute

rheumatic fever

1006 Causal 0 High High High

10006 Acute rheumatic fever

1007 Causal 0 High High High

10007 Acute rheumatic fever

1008 Causal 0 High High High

10008 Acute

IDrelidentification number of Relation table;TypeRelationtype of relation;NumberFindnumber of findings;Sensit sensitivity;Specifspecificity; Predictpredictive value; Column ‘Relations’

shows IDdis from Table3.9– ‘Disease’, IDfind form Table3.10– ‘Findings’ or IDrel from this table

There are two levels of relations: primary and secondary that is formed from primary.

Because of that, these secondary relations are ‘relations of the relations’ and they have the same format of IDrel in field relations. For example, 10011 is complex and is derived from relations 10008 (necessary one findings-syndrome), 10009 (neces-sary two findings) and 10010 (neces(neces-sary one findings). Complex relation 10013 is derived from 10012 which is the same as 10008 but necessary are two findings-syndromes and 10010 (necessary one findings) as can be seen from the text that was transformed.

Retrieval from this knowledge base is the same as it was discussed in previous example. However, in this case there are more syndromes than in the first example and Relation table is complex. In addition, there are no separate knowledge base tables for some disease. They are unique for all disease as can be seen from ID numbers in the tables but they are showed separately in order to simplify presentation.

References

1. Decision-Making in Clinical Medicine. In Fauci, Branuwald, Kasper, Hauser, Longo, Jameson and Lorenco eds. Harrison’s Principles of Internal Medicine. Seventeenth edition. (The McGraw-Hill Companies, Inc. New York: 2008: 16–23).

2. Kong Guilan, Xu Dong-Ling, Yang Jian-Bo. Clinical decision support systems: A review on knowledge representation and inference under uncertainties. International Journal of Compu-tational Intelligence Systems 1 (2008) 159–167.

3. Berner E and La Lande T. Overview of Clinical Decision Support Systems in Berner ES. Clinical Decision Support Systems: Theory and Practice (Health Informatics) (Springer, New York, 2007: 3–22).

4. Carter J. Design and Implementation Issues in Berner ES. Clinical Decision Support Systems:

Theory and Practice (Health Informatics) (Springer, New York, 2007: 64–98)

5. Miller R and Geissbuhler A. Diagnostic Decision Support Systems Systems in Berner ES. Clinical Decision Support Systems: Theory and Practice (Health Informatics) (Springer, New York, 2007: 99–125).

6. Long WJ. Medical informatics: reasoning methods. Artif Intell Med. 2001 23:71–87.

7. Perry CA. Knowledge bases in medicine: a review. Bull Med Libr Assoc. 1990 78:271–82.

8. Bennett CC, Hauser K. Artificial intelligence framework for simulating clinical decision-making: A Markov decision process approach. Artif Intell Med. 2012 Dec 31. doi:pii:

S0933-3657(12)00151-0.10.1016/j.artmed.2012.12.003.

9. Horn W. AI in medicine on its way from knowledge-intensive to data-intensive systems. Artif Intell Med. 2001 Aug;23(1):5–12.

10. Berrios DC, Kehler A, Fagan LM. Knowledge requirements for automated inference of medical textbook markup JAMIA (1999) S676–S80

11. Shankar RD, Tu SW, Martins SB et al. Integration of textual guideline documents with formal guideline knowledge bases JAMIA (2001) S617–21

12. Osheroff JA, Teich JM, Middleton B et al. A roadmap for national action on clinical decision support . JAMIA. 14 (2007) 141–145

13. Oberkampf H, Zillner S, Bauer B and Hammon M. Towards a ranking of likely diseases in terms of precision and recall. Proceedings of the 1st International Workshop on Artificial Intelligence and NetMedicine, Montpellier, France, 2012. 11–20.

14. Vecchio TJ. Predictive value of a single diagnostic test in unselected populations. N Engl J Med 274 (1966) 1171–73

15. Longo, Fauci, Kasper, Hauser, Jameson and Lorenco eds. Harrison’s Principles of Internal Medicine. Eighteenth edition. (The McGraw-Hill Companies, Inc. New York, 2012).

16. Systemic lupus erythematosus. In Fauci, Branuwald, Kasper, Hauser, Longo, Jameson and Lorenco eds. Harrison’s Principles of Internal Medicine. Seventeenth edition. (The McGraw-Hill Companies, Inc. New York, 2008, 2075–2082).

17. Acute rheumatic fever. In Fauci, Branuwald, Kasper, Hauser, Longo, Jameson and Lorenco eds. Harrison’s Principles of Internal Medicine. Seventeenth edition. (The McGraw-Hill Companies, Inc. New York, 2008, 2092–2095).

18. Davison A, Cameron S, Rits E, Grunfelt J, Wenearls C, Ponticelli C and Ypersele C eds.

Oxford Textbook of Clinical Nephrology. Third edition. (Oxford University Press, Oxford, 2005).

19. Markovic´ Z, Rasˇkovic´ M, Ognjanovic´ Z. A Logic with Approximate Conditional Probabilities that can Model Default Reasoning. International Journal of Approximate Reasoning 49 (2008) 52–66

20. Perovic´ A, Ognjanovic´ Z, Rasˇkovic´ m, Radojevic´ D. Finitely additive probability measures on classical propositional formulas definable by Godel’s t-norm and product t-norm, Fuzzy Sets and Systems 169 (2011) 65–90

21. D. Doder. A logic with big-stepped probabilities that can model nonmonotonic reasoning of system P. Publications de l’Institut Mathe´matique, ns. 90(104): 13–22, 2011.

22. D. Doder, J. Grant, Z. Ognjanovic´. Probabilistic logics for objects located in space and time.

To appear in Journal of logic and computation, doi:10.1093/logcom/exs054.

23. A. Ilic´-Stepic´, Z. Ognjanovic´, N. Ikodinovic´, A. Perovic´, A p-adic probability logic, Mathe-matical Logic Quarterly, vol. 58 (4–5), 263–280, 2012.

24. Z. Ognjanovic´, Z. Markovic´, M. Rasˇkovic´, D. Doder, A. Perovic´: A propositional probabilistic logic with discrete linear time for reasoning about evidence. Ann. Math. Artif. Intell. 65(2–3):

217–243, 2012.

25. Kawamata F, Kondoh M, Mori C, Endoh J, Takahashi T. Computer-aided clinical laboratory diagnosis in conjunction with the electronic medical textbook. Medinfo. 8 (1995) 955 26. Miller RA, McNeil MA, Challinor SM et al. The internist-1/quick medical reference

project–status report. West J Med. 145 (1986) 816–22

27. Berrios DC, Kehler A, Kim DK et al. Automated text markup for information retrieval from an electronic textbook of infectious disease JAMIA (1998) S975–5

28. Garg AX, Adhikari NK, McDonald H et al. Effects of computerized clinical decision support systems on practitioner performance and patient outcomes: a systematic review. JAMA.

293 (2005) 1223–38.

29. Kawamoto K, Houlihan CA, Balas EA et al. Improving clinical practice using clinical decision support systems: a systematic review of trials to identify features critical to success. BMJ.

330 (2005) 765–73

30. Patwardhan MB, Kawamoto K, Lobach D et al. Recommendations for a clinical decision support for the management of individuals with chronic kidney disease. Clin J Am Soc Nephrol. 4 (2009) 273–83