introduction to medicine

1. INTRODUCTION TO
MEDICINE
Dr.Bilal Natiq Nuaman,MD
C.A.B.M. , F.I.B.M.S. , D.I.M. , M.B.Ch.B.
Lecturer in Al-Iraqia Medical College
2018-2019

3. Doctors specializing in internal medicine are called internists,
Internal Medicine
The branch of medicine that deals with the diagnosis and
nonsurgical treatment of diseases affecting adults within its
scope .
The medical specialty dealing with the prevention, diagnosis,
and treatment of adult diseases.
Doctors specializing in internal medicine are called internists
or physicians

4. Scope of Subspecialties of Internal Medicine
Cardiology, dealing with disorders of the heart and blood
vessels
Endocrinology, dealing with disorders of the endocrine system
and its specific secretions called hormones
Gastroenterology, concerned with the field of digestive
diseases
Hematology, concerned with blood, the blood-forming organs
and its disorders.
Infectious Diseases, concerned with disease caused by a
biological agent such as by a virus, bacterium or parasite

5. Nephrology, dealing with the study of the function and
diseases of the kidney
Pulmonology, dealing with diseases of the lungs and the
respiratory tract
Rheumatology, devoted to the diagnosis and therapy of
rheumatic diseases.
Neurology dealing with diseases of nervous system
Medical Oncology, dealing with the chemotherapeutic
(chemical) treatment of cancer
Poisoning and Critical Care

6. Internal Medicine , Management ,
sequence of roles
1-DIAGNOSIS
2-TREATMENT
3-PREVENTION

7. Medical Diagnosis
• Sequence of Diagnosis
1--History taking from patient (record patient
symptoms like: dyspnea, chest pain, vomiting,
ankle swelling, weight loss, cough,…..etc )
2--Examination of the patient (looking for physical
signs like: hepatomegaly, murmur, rhonchi,
tachycardia, Exopthalmos, facial palsy…..etc )
3--Investigations (ECG, CXR, RBS, abdominal US,
Echo, sputum for AFB……etc)

8. Symptom vs sign
• A symptom(complaint) is subjective feeling from
the patient point of view.
• A symptom is what the patient experiences about the
disease.
• Symptoms can only be experienced, they are not able to
be observed or measured objectively.
• Pain is a symptom. I do not know you are having pain
unless you tell me. Nausea is also a symptom, as are:
chills, numbness, fatigue, vertigo, malaise, itching,
stomach cramps, burning on urination, etc.

9. • A sign is an objective physical manifestation of
disease.
• It is an objective finding, something one can observe and
measure.
• A rapid pulse, a high temperature, a low blood pressure,
an open wound, bruising, etc. are all signs.
• Signs give a more definite indication of the presence of a
particular disease to the physician.
So in the simplest form, signs are observations of
the doctor and symptoms are the experiences of
the patient.

10. Patients commonly have complaints
(symptoms). These symptoms may or may
not be accompanied by abnormalities on
examination (signs) or on laboratory
testing.
Conversely, asymptomatic patients may have
signs or laboratory abnormalities, and
laboratory abnormalities can occur in the
absence of symptoms or signs.

11. History Taking

17. Approach to patient = Management of patient

19. PATIENT
Mrs. S is a 58-year-old woman who comes to an urgent care clinic
complaining of painful swelling of her left calf that has lasted for
2 days. She feels slightly feverish but has no other symptoms
such as chest pain, shortness of breath, or abdominal pain. She
has been completely healthy except for hypertension,
osteoarthritis of her knees, and a cholecystectomy, with no
history of other medical problems, surgeries, or fractures. Her
only medication is hydrochlorothiazide. Physical exam shows
pitting edema of left leg and the circumference of her left calf is
3.5 cm greater than her right calf, with. The left calf is uniformly
red and very tender, and there is slight tenderness along the
popliteal vein and medial left thigh. There is a healing cut on her
left foot. Her temperature is 38.5°C. The rest of her exam is
normal.

20. CONSTRUCTING A DIFFERENTIAL DIAGNOSIS
Step 1: Identify the Problem
Problem lists should begin with the acute problems, followed by
chronic active problems, ending with inactive problems.
Mrs. S’s problems are (1) painful left leg edema with erythema, (2)
hypertension, (3) osteoarthritis of the knees, and (4) status post
cholecystectomy.
Step 2: Frame and the Organize Differential Diagnosis
starts with the distribution of the edema: generalized versus unilateral
and limb versus localized. The causes of edema are fairly distinct for
each of these subcategories. For instance, heart failure and chronic
kidney disease cause generalized not unilateral edema.

21. Step 3: Limit the Differential Diagnosis
Mrs. S has acute unilateral leg edema, a pivotal point that leads
to a limited portion of the edema differential.Diagnostic
possibilities are now narrowed to a distinct subset of diseases
that can be organized using an anatomic framework:
A. Soft tissue: Cellulitis
B. Calf veins: Distal deep venous thrombosis (DVT)
C. Knee: Ruptured Baker cyst
D. Thigh veins: Proximal DVT
E. Pelvis: Mass causing lymphatic obstruction

22. Step 4: Use History and Physical Exam Findings to
Explore Possible Diagnoses
Consider the risk factors for each of the diagnostic
possibilities as well as their associated symptoms
and signs. For example, Cellulitis often follows skin
injury, and physical exam shows erythema and
tenderness. DVT is more frequent in patients with
underlying malignancy or recent immobilization,
and there may be shortness of breath if the clot
has embolized.

23. Step 5: Rank the Differential Diagnosis
Mrs. S has a constellation of symptoms and signs supporting the
diagnosis of cellulitis as the leading hypothesis: fever; an entry site
for infection on her foot; and a red, tender, swollen leg. Even
without risk factors for DVT, the active alternatives are proximal
and calf DVT, being both common and “must not miss” diagnoses.
If cellulitis and DVT are not present, ruptured Baker cyst and a
pelvic mass should be considered.

24. Step 6: Test Your Hypotheses Determine the Pretest
Probability
There are several ways to determine the pretest
probability of your leading hypothesis and most
important (often most serious) active alternatives:
use a validated clinical decision rule (CDR), use
prevalence data regarding the causes/etiologies of a
symptom, and use your overall clinical impression.

25. Consider the Potential Harms
Consider the potential harms of both a missed diagnosis and the
treatment.
A. It is very harmful to miss certain diagnoses, such as MI or
pulmonary embolism, while it is not so harmful to miss others,
such as mild carpal tunnel syndrome. You need to be very
certain that life threatening diseases are not present (that is,
have a very low pretest probability), before excluding them
without testing.
B. Some treatments, such as thrombolytics, are more harmful
than others, such as oral antibiotics; you need to be very certain
that potentially harmful treatments are needed (that is, the
pretest probability is very high) before prescribing them without
testing.

26. You are unable to find much information about estimating
the pretest probability of cellulitis. You consider the
potential risk of starting antibiotics to be low, and your
overall clinical impression is that the pretest probability of
cellulitis is high enough to cross the treatment threshold, so
you start antibiotics.
You consider the pretest probability of DVT to be low, but
not so low you can exclude it without testing, especially
given the potential seriousness of this diagnostic possibility.
You have read that duplex ultrasonography is the best
noninvasive test for DVT. How good
is it? Will a negative test rule out DVT?

27. Mrs. S has a normal duplex ultrasound scan. proximal
DVT has been ruled out. Since duplex ultrasound is less
sensitive for distal than for proximal DVT, clinical
follow-up is particularly important. Some clinicians
repeat the duplex ultrasound after 1 week to confirm
the absence of DVT, and some clinicians order a D-
dimer assay. When she returns for reexamination after
2 days, her leg looks much better, with minimal
erythema, no edema, and no tenderness. The clinical
response confirms your diagnosis of cellulitis, and no
further diagnostic testing is necessary.

29. THANK YOU