Diagnostics
Department of endocrinology
affiliated hospital of Cheng De Medical College
Jiaoyue Chen (陈娇月）
2022-02-28
A case
An old person be sent to a hospital by 120 because of
fainting, everybody pays attention to treatment, but What's
the most important thing to do before treatment?
No correct diagnosis
No appropriate treatment
How to diagnose?
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contents
• What to learn?
• How to learn?
• what to achieve?
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Human Anatomy,
Histoembryology,
Physiology, Biochemistry
and Molecular Biology,
Medical Genetics,
Microbiology and
Immunology, Pathology,
Pharmacology,
Importance of Diagnostics
Bridge （桥梁）
Basic courses
Key
（钥匙）
Diagnostics
A fundamental course
of clinical medicine
临床医学的基础课程
Clinical medicine
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What is Clinical Diagnostics?
•basic theory (基本理论)
•basic knowledge (基本知识)
“three basics”
•basic skill (基本技能)
Identification：
Basic methods, inquiry,
physical examination, la
boratory tests, assistant e
xaminations...
Analysis:
Basic knowledge, compre
hensive analysis, methods
and procedures of clinical
thinking
make the diagnosis and reach the therapeutic strategies
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Contents of Clinical
Diagnostics
Symptomatic diagnosis (症状诊断)
Physical diagnosis (检体诊断)
Laboratory examination(实验室检查)
Assistant examination（辅助检查）
Medical record（病历）
Diagnostic processes and the way of
clinical thinking（临床诊断思维方法）
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Symptomatic Diagnosis
(症状诊断)
History taking（病史采集 )--- Interrogation (问诊）
Ask about subjective abnormalities or discomfort
Complaints (主诉) --- symptoms (症状）or signs(
体征）
Symptomatic Diagnosis (症状诊断) --- impression
diagnosis
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Symptomatic Diagnosis
Symptom （症状）
Subjective sensation that patient describes
Fever
Cough
Palpitation
Pain
Dyspnea
Vertigo
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Sign （体征）
Abnormality observed by the physician or patient
jaundice
Edema
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difference
• symptom：subjective，sign: objective.
• Abdominal pain: is a symptom, it is the patient
perceive.
• gross blood in the stool:
is a sign, it is evidence that can be recognized
by the patient, physician, nurse, or someone else.
Is also a symptom, the patient narrative.
• “I’ve found a lump in my neck” (symptom), and
the examiner can palpate a mass ( sign).
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Symptomatic Diagnosis depends on
Interrogation (inquisition/inquiry)
• To get the medical history in detail of a patient’s illness
• The history is taken at initial contact between physician
and patient
• As some key points might be overlooked by the patients,
one will ask many searching questions to make the history
more informative and complete, at the same time avoid
suggesting answers
• Occasionally to interrogate his family member
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Physical Diagnosis
Physical examination (体格检查): doctors
systematically observe and examine patients with
their own senses or traditional assistive instruments to
reveal normal and abnormal signs of the body
Inspection (视）
Palpation （触）
Percussion （叩）
Auscultation （听）
Smelling（嗅 ）
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Physical Diagnosis
traditional assistive instruments
stethoscope, percussion hammer,
sphygmomanometer(electronic sphygmomanometer),
thermometer,(infrared thermometer), ophthalmoscope
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Stethoscope(听诊器)
an instrument that a doctor
uses to listen to your heart and
breathing.
consists of a small disc that is
placed on your body,
connected to a hollow tube
with two pieces that the doctor
puts in his or her ears.
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Sphygmomanometer(血压计)
an instrument for measuring blood pressure
typically consisting of an inflatable rubber
cuff which is applied to the arm and
connected to a column of mercury next to a
graduated scale enabling the determination
of systolic and diastolic blood pressure by
increasing and gradually releasing the
pressure in the cuff
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Laboratory examination
Physical methods
Chemical methods
Biological method
blood
excretion
secretion
cell or tissue
etiology
pathophysiology
histopathology
Three routine: blood, urine, feces routine
Liver and kidney function, Glucose, Lipids, electrolytes,
Serum cardiac markers,
Hepatitis markers,
Tumor markers
Endocrine hormones, Immunologic tests of infection
Pathogenic diagnosis of bacterial infection
Cytogenetic analysis
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assistant examination
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X-ray film
x-ray computerized tomography (CT)
electrocardiography (ECG )
Ultrasonic imaging
magnetic resonance imaging (MRI)
Positron Emission Tomography (PET)
Endoscopy
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X-ray film
The right upper lobe
pneumonia
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CT
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ECG〔electrocardiography〕
Recording of the moment-tomoment electromotive forces of the
HEART as projected onto various
sites on the body's. The recording
is monitored by a tracing on slow
moving chart paper or by
observing it on a cardioscope.
R
L
N
F
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ECG
Acute inferior wall infarction
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Ultrasonic imaging
The visualization of deep structures of the body by recording
the reflections of echoes of ultrasonic waves directed into the
tissues.
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MRI
Non-invasive method of demonstrating internal anatomy based on the
principle that atomic nuclei in a strong magnetic field absorb pulses
of radiofrequency energy and emit them as radio waves which can be
reconstructed into computerized images.
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PET
Tomography using emissions from radionuclides and a
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computer procedure to reconstruct the image.
Endoscopy
bronchoscope,
gastroscope,
colonoscope
…
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Medical record
Medical record is a systematized way of storing
the required data, information and other relevant
documents
Specific
requirement in
terms of format
and content
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Steps to diagnose a disease
• (1) Data collection: medical history, physic
al examination, laboratory tests and assist
ant examinations
• (2) Analyze comprehensive data and form
an impression
• (3) Verify or correct the diagnosis
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Data collection
analysis、evaluate、arrange
clinical
experience
clinical
knowledge
impression diagnosis
Verify and correct the
diagnosis
schematic diagram of disease diagnosis steps
Basic principles of clinical diagnosis
(1) Seek truth from facts
(2) Principle of monism
(3) a common and prevalent disease based o
n morbidity and disease spectrum
(4) Consider organic disease first, and then fu
nctional disease
(5) Consider treatable diseases first
(6) The principle of simplifying the thinking pro
cess
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the key of learning method
• Strong sense of service
• In theory, the clinical significance of sympt
oms, signs and experimental results is ma
stered.
• In practice, the basic skills of interrogation
and physical examination are repeatedly t
rained.
• New technologies are important, but they c
an't replace basic skills.
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methods of learning diagnostics
(differents from basic courses)
1.Foster good medical ethics and practices
• Only careful care and consideration，you
can learn something,
• Highly degree of flexibility and initiative
in work
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methods of learning diagnostics
2.Pay attention to practices
• Master the right way
• Emphasize standardization and normalizat
ion
• Contact patients, bedside based learning
, and active learning
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methods of learning diagnostics
3.familiar with the diagnosis steps,understan
d your own role,combine theory with practice
• gather information
history taking
Physical examination,
Lab exam, Assistant examination
• observe the whole process of disease
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Diagnostic processes and the way of clinical thinking
judge the truth and value
sort positive findings in order of importance
choose 1-2 major clinical manifestation，make impression diagnosis
choose from the listed diagnosis
all clinical manifestation
can be explained
other possibilities，
make a final diagnosis
review all linical data，confirm that diagnosis consistant
Objective to learn
• Can independently carry out systematic
and targeted inquisitions, and master the
internal relationship and clinical
significance between symptoms and signs
of the chief complaint.
• Can carry out systematic, comprehensive,
focused and orderly physical examination
in a standardized way
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Objective to learn
• Familiar with the operation techniques of
routine laboratory tests such as blood,
urine and feces and the purpose and
significance of common clinical tests.
• Master the operation procedure of ECG
machine, familiar with normal ECG and
abnormal ECG image analysis.
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Objective to learn
• Can systematically organize the data of
inquisitions and physical examination, and
write complete medical records with
correct format, smooth writing, clear
expression, standard font.
• Can make an impression diagnosis
based on the analysis of the history,
physical examination, laboratory
examination and assistant examination.
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Important aspects
 The diagnostic process is very complex(复
杂) ，The number of facts that can be
collected in a detailed medical history （问诊）
and in thorough physical examination（体格检
查）， The laboratory tests or specialized
technical procedures are numerous and
costly.
 Modern & advanced assistant
techniques have their limitations.
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Important aspects
• It can’t reduced the importance of
certain parts of the classic P. E
• It should be avoided to neglect
fundamental methods
• Interrogation
• Physical examination
• Scientific clinical thinking
（正确思维方法）
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Wishes
• From a medical student to a clinician who
can make a preliminary diagnosis, it takes
a lot of clinical practice to achieve it
gradually. Studying diagnostics is only an
important beginning of a clinical medicine
course.
• A journey of a thousand miles begins with
a single step, and efforts will be rewarded!
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How to diagnose nCOV-2019?
1、chief complaint dry cough, fatigue, fever
2、physcical examination T.
3、personal history (Epidemiological history)
4、Lab exam Novel coronavirus nucleic acid
test positive
5、Assistant exam(X-ray, CT imaging)
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