Clinical Intelligent Diagnosis Path Based on the Chief Complaint

ZHOU Xio-Qing, TONG Tin-Ho, ZENG Yi-Di,c, ZHONG Lu

a.Hunan University of Chinese Medicine, Changsha, Hunan 410208, China

b.Provincial Key Laboratory of TCM Diagnostics, Hunan University of Chinese Medicine, Changsha, Hunan 410208, China

c.Collaborative Center for Research and Innovation of Digital Chinese Medicine, Hunan University of Chinese Medicine, Changsha, Hunan 410208, China

d.Ruikang Hospital Affiliated to Guangxi University of Chinese Medicine, Nanning, Guangxi 530011, China

Keywords

Chief complaint

Intelligent diagnosis

TCM diagnosis

Correlation analysis

Combination of four diagnostic methods

Symptom pair

Symptom group

ABSTRACT

Goals of traditional Chinese medicine (TCM)include precision,accuracy, and recognition by clinical practice.Establishment of a diagnosis and treatment system that closely conforms to the principle-method-recipe-medicines system and derivation of an accurate diagnosis and treatment plan should be considerations of TCM.Artificial intelligence research based on computer technology is one of the effective ways to solve this problem.In the research of intelligent diagnosis path, reflecting the characteristics of the overall view and dialectical treatment of TCM such as “Combination of four diagnostic methods” “overall examination” “combination of disease and syndrome” and“treatment individualized to patient, season and locality” are key for successful research of artificial intelligence in TCM diagnosis or recognition by clinical practice.

1 Introduction

Traditional Chinese medicine (TCM)is a system of diagnosis and treatment that combines diseases,syndromes and symptoms and integrates principles,methods, formulas and medicinal materials.TCM has accumulated rich practical experience,techniques and theories in the field of medicine.Its basic principles for diagnosis (i.e., a combination of four diagnostic methods, overall examination, and combination of disease and syndrome)as well as treatment individualized to the patient, season and locality, etc., make TCM more characteristic and feasible in modern diagnosis path research.Treatment based on syndrome differentiation is the core of clinical diagnosis and treatment in TCM,which offers an advantage of TCM compared with the diagnosis and treatment system of modern medicine;its theoretical system fully reflects the effectiveness of TCM theories in practice after thousands of years of clinical practice and validation[1].TCM is advanced in its concept of diagnosing diseases mainly through overall, dynamic and personalized comprehension of body status; however, its methods rely on experience,which restricts the ability of TCM to achieve its development[2].The chief complaint highly refines disease conditions and is the core of TCM clinical diagnosis and treatment.Understanding the chief complaint; combining the four diagnostic methods;determining the etiology, disease nature and disease site; as well as performing correlation analysis and quantitative diagnosis are the key steps to improve the accuracy of disease differentiation and syndrome differentiation.Only when the disease differentiation and syndrome differentiation are accurate and objective can guarantee the principles, methods,formulas and medicinal materials will be accurate in each step, and the efficacy can be ensured.Therefore,exploring the diagnosis approach of combining the four diagnostic methods and correlation analysis based on the chief complaint is of practical significance.

2 Chief Complaint

2.1 Definition of chief complaint

The national “12thFive-year Plan” teaching materialDiagnostics[3]defines the chief complaint as follows:“Chief complaint is the patient’s description of the reason for consultation, i.e., the most painful symptoms and signs, as well as their durations, which prompt the patient to seek medical attention”.Its succinct generalization includes the main symptoms,signs and urgent needs of the patient in the current consultation.

2.2 Basic elements of chief complaint

A normal chief complaint must have two elements,namely, symptoms/signs and duration.Symptoms/signs are generally known as the main symptoms and are not more than three in number.The duration is calculated from the time of the initial onset of symptoms/signs.If the symptoms or signs involved in the chief complaint are related to certain sites, the sites should be included.For example, the chief complaints “pain for 10 days” and “edema for 1 month” are incomplete and should be changed to“headache for 10 days” and “l(fā)ower limb edema for 1 month”.See Table 1 for the structure of a normal chief complaint.

2.3 Diagnosis and treatment path with chief complaint as the entry point

A “chief complaint” usually includes one or two main symptoms.Generally, in-depth and detailed analysis of the internal correlations or characteristics of these symptoms can provide a sufficient basis for solving the problem.The main symptom is the externally manifested phenomenon, the reflection of the nature of disease, and the clue and guide for understanding the disease and syndrome[4].The path for disease diagnosis and syndrome differentiation around the chief complaint can be determined according to the following steps: (1)Determination of the chief complaint: The chief complaint is determined according to the symptoms affecting the patient’s quality of life and the patient’s self-feelings and demands, and it is considered the main clue for diagnosis.(2)Longitudinal excavation: The chief complaint is longitudinally excavated by asking about the exact site, nature, degree, inducing factors,duration, frequency, form of existence (e.g.,paroxysmal, persistent), etc.related to the onset of the chief complaint and describing the characteristics of the chief complaint in depth and in detail.(3)Horizontal excavation: The chief complaint is horizontally excavated through the four diagnostic methods, including its related concomitant symptoms and systemic symptoms, identification of the symptom pairs and symptom groups through correlation analysis, and analysis of the associations among the symptoms.(4)Differentiation of the syndrome elements: Microscopic manifestations are innovatively correlated with macroscopic symptoms by means of modern auxiliary examination methods,comprehensively understanding the disease conditions, and perfecting the data for diagnosis,thereby providing the basis for differentiating the syndrome elements related to the disease site and disease nature.(5)Integrate, collate and analyze the disease condition data, derive the correct diagnosis and treatment strategies according to the differentcharacteristics of relevant “diseases” and“syndromes”, and determine the corresponding drug formulas.Figure 1 depicts the detailed steps of the chief complaint diagnosis path.

Table1 Composition of a normal chief complaint

3 Longitudinal Excavation of the Chief Complaint

Symptoms can often indicate the existence of a disease at an early stage.Therefore, doctors should be especially adept at grasping and confirming the main symptoms from the various symptoms or signs described by the patients and then excavating longitudinally around the main symptoms.Main symptoms and signs of a disease are the external manifestations of the pathological nature of the disease; each disease has its own specific main symptom(s).The main symptom(s)can be one or several in number and is/are often closely related to the “chief complaint”[5].“Chief complaint” is the most significant symptom or sign that urges the patient to seek medical attention.It generally includes only one or two symptoms, which are often the patient’s main symptoms at the presentation stage.Clinically, a phenomenon often exists, i.e., the patient feels physical discomfort, but pathological changes and laboratory abnormalities cannot be detected during the consultation.At this time,symptoms may be the only manifestation of the disease.In addition, as symptoms have subjective characteristics, information can only be obtained through interrogation; therefore, interrogation is very important in the accurate collection of symptoms.In the interrogation (investigation)of symptoms,attention should be paid to the combination of comprehensiveness and focus.Comprehensiveness means that the occurrence of a symptom often involves the site, nature, degree and other aspects, so attention should be paid to avoid omission.Focus means the combination of interrogation (four diagnostic methods)with disease differentiation and the interrogation (investigation)of highly correlated concomitant symptoms around the chief complaint.Avoid mechanically conducting non-directional interrogation according to the “ten-question song”,i.e., “grasp the main symptoms, and ask deeply and comprehensively”.If the chief complaint is“abdominal pain”, ask comprehensively and in detail the degree of pain (severe pain or dull pain), nature(cold pain, pricking pain, empty pain, etc.), site(upper abdominal pain, lower left abdominal pain,etc.), time (more than one month, morning pain,after-meal pain, etc.), frequency, inducement (eating raw or cold food, catching cold, etc.), and aggravating or relieving factors (preferring warm, refusing compression, etc.), and then ask about other concomitant symptoms to complete the diagnosis path.

4 Horizontal Excavation of Chief Complaint

A single symptom viewed in isolation has limited diagnostic significance.In western medicine,instrumental examinations are often applied to achieve a more detailed diagnosis.If the hospital does not have the required equipment, your doctor will ask you to visit a more fully-equipped hospital;otherwise, it would be difficult to make a correct diagnosis.In TCM, if a single disease and other related conditions (including presence or absence of symptoms)are arranged and combined for correlation analysis, its diagnostic significance will be greatly enhanced.In TCM, the symptoms appearing in the chief complaint are taken as the main clue, and horizontal excavation is performed on the closely related symptoms around the main symptoms.Two main points are considered, i.e., symptom pair and symptom group.

4.1 Symptom pair

After the onset of disease, people seldom have a single symptom, and the symptoms often appear in pairs or groups.The appearance of symptoms usually follows the rule and characteristic of pairs and groups, which are mostly related to diseases and syndromes and do not change according to the doctor’s will.Therefore, a symptom pair can be defined as a pair of symptoms or signs with internal association occurring at the same stage in the disease course[6].For example, “putrid belching” and “acid regurgitation” can be viewed separately as two conditions, namely “belching combined with putrid odor, i.e., the odor of putrid food in the stomach is discharged from the mouth” and “the acid fluid in the stomach attacks the oral cavity and overflows the pharynx, but it cannot be discharged and is swallowed”.However, the symptoms are often attributed to liver-Qi invasion of the stomach and food stagnation and often occur at the same stage in the disease course; thus, they are regarded as a symptom pair.For example, night fever and morning coolness, feeling of the need to defecate but incomplete defecation, restlessness and irritability,and swift digestion and rapid hungering, etc., can be regarded as symptom pairs.

According to the definition, a symptom pair has three major features[7]: (1)Simultaneous occurrence at a certain stage of the disease or syndrome is a feature that emphasizes the timeliness of symptom occurrence.The symptoms in a pair must occur simultaneously with the current disease or syndrome, but one of the symptoms may occur first, e.g., aversion to cold occurs first, and persistent aversion to cold is followed by fever.(2)The symptoms are associated with the disease or syndrome and have the internal correlation of occurring at the same time; in addition,the mechanism for occurrence at the same stage in the disease course can be explained.(3)Although they occur in pairs, each symptom is independent.The pair is formed by different parts, properties, and time, such as night fever and morning coolness, and tidal fever and night sweating.

4.2 Symptom group

A symptom group is a group of internally related symptoms and signs that reflect the same disease site or disease nature, e.g., the superposition of fever,flushed face, halitosis, dry mouth, yellow urine, dry stool, red tongue, yellow tongue coating, rapid pulse,and other symptoms and signs that constitute the symptom group of internal heat excess syndrome.Due to different types and severity of diseases, the numbers, degrees, or sites of symptoms (members)exhibited by the symptom groups are different, but their essential pathological attributes are consistent.

The symptoms and signs forming a symptom group reflect the same disease site and disease nature.Some symptom groups can be observed in the whole body, while others are relatively localized.This is also related to the disease site and other factors.The appearance of a symptom group plays the role in indicating the site and nature of the disease and has great significance to disease diagnosis and syndrome differentiation.For example, new onset of aversion to wind and coldness, slight fever and sweating, or nasal congestion and sneezing indicates that the disease is located on the exterior; lower abdominal contracture and cold pain, dysmenorrhea,delayed menstruation, and dark purple blood patches indicate that the disease is located in the uterus.

5 Establishment of A Simple Path

In the process from the chief complaint to the symptoms and then to the name of the disease or syndrome, the influence of the complex relationship among symptoms on the contribution to diagnosis cannot be ignored.In the process of diagnosis from the symptoms to the disease or syndrome, various previous quantitative diagnostic methods through syndrome differentiation based on syndrome elements, although weighted, lack prioritization,ignore the internal relationship among symptoms,and cannot fully reflect the connotation of disease diagnosis and syndrome differentiation[8].Since the four diagnostic methods in TCM are put forward to reveal the complicated relationship among symptoms, when calculating their degrees of contribution to disease diagnosis and syndrome differentiation, one must pay attention to whether the combination has a gain relationship (1 + 1 > 2)or loss relationship (1 + 1 < 2), instead of just applying the previous uniform superposition mode of 1 + 1 = 2.Identification of the rules from the correlation among symptoms to establish a simple path to more quickly and accurately comprehend the etiology, site and nature of the disease, and thus accurately differentiate the syndrome and disease, is a matter that medical professionals should consider seriously.This often reflects their experience and expertise.See Table 2 for the details.

6 Common Correlation Analysis

Apart from systematic and comprehensive analysis on the knowledge points of TCM[9], we also need to identify the rules from the correlation among symptoms to understand the etiology, site, and nature of the disease, and thus differentiate the syndrome and disease.This is a problem that TCM medical professionals should seriously consider exploring to improve the quality of diagnosis.

Table2 Comparison of the simple path and complete path

6.1 Correlation analysis -- main symptoms

For example, slight thirst and heavy thirst reflect the idea of quantitative diagnosis.The former is mild,while the latter is severe.When a patient feels thirsty but wants to gargle and not swallow the water, the diagnosis is blood stasis based on qualitative diagnostic thinking; when a patient feels thirsty but vomits immediately after drinking, it indicates that the water stagnates in the stomach.

6.2 Correlation analysis -- chief complaint

Cough and clear nasal discharge accompanied by aversion to cold for one day suggest exogenous cough and wind-cold invading the lungs; repeated cough for more than 3 months accompanied by chest and hypochondrium pain for 3 days suggests cough due to internal injury and pleural effusion (pleurisy);repeated cough for more than ten years aggravated by palpitation and edema for one month suggests cough due to internal injury as well as phlegm-fluid retention (pulmonary heart disease).

For the above-mentioned clinical syndrome cases, through “qualitative” “quantitative” and “positioning” analysis, the clinical diagnostic thinking is clearer.Overall, it looks like a complex problem, but after the regular decomposition of the complex problem, it is transformed into relatively simple problems in local areas, making the syndrome differentiation more objective and accurate.

7 Conclusions

There is a phenomenon in the clinical practice of TCM as follows: “Ten doctors of TCM would prescribe ten different formulas for the same person.”Regarding the cause of this problem, we have written an articleDiscussion on the Possibility and Mechanism of “Same Disease and Same Syndrome”Cured by Various Prescriptions[10], which answers this question from the perspective of prescriptions.However, it seems incomplete today, and the following questions exist: (1)Is the collection of symptoms and signs by the four diagnostic methods incomplete? (2)Is the positioning error of symptoms and signs by the four diagnostic methods a common problem? (3)Is there any difference in judging the syndrome type related to the main symptoms or signs? (Different clinical experience and different emphasis on certain symptoms and signs often lead to different diagnostic understandings).For objective diseases and syndromes, the results of syndrome differentiation are too subjective, while subjective conclusions tend to deviate from the laws of objective reality.To improve the reliability of subjective conclusions, it is necessary to clearly understand and analyze the basic path of TCM diagnosis, explore the internal basic laws, and analyze the key steps and components of the basic path to provide an important basis for intelligent calculation[11].

Acknowledgements

We thank for the funding support from the Open Fund Project of State Key Subjects of Chinese Medicine Diagnostics, Hunan University of Chinese Medicine (No.2015ZYZD01).

Competing Interests

The authors declare no conflict of interest.