Davidson&Harrison MCQs(CVS)

internal medicine final 23-24.pdf

هاريسون&دايفدسون تم بعون الله🤝😔😂

Davidson MCQs
Harrison MCQs

التوضيح🪄

Diuretics are contraindicated in patients with lymphedema and may
cause depletion of intravascular volume and metabolic abnormalities. Patients should be encouraged to
participate in physical activity; frequent leg elevation can reduce the amount of edema. Psychosocial
support is indicated to assist patients cope with anxiety or depression related to body image, self-esteem,
functional disability, and fear of limb loss. Physical therapy, including massage to facilitate lymphatic
drainage, may be helpful. The type of massage used in decongestive physiotherapy for lymphedema
involves mild compression of the skin of the affected extremity to dilate the lymphatic channels and
enhance lymphatic motility. Multilayered, compressive bandages are applied after each massage session to reduce recurrent edema. After optimal reduction in limb volume by decongestive physiotherapy, patients can be fitted with graduated compression hose. Occasionally, intermittent pneumatic compression devices can be applied at home to facilitate reduction of the edema. Liposuction in conjunction with decongestive physiotherapy may be considered to treat lymphedema, particularly postmastectomy lymphedema. Other surgical interventions are rarely used and are often not successful in ameliorating lymphedema. Microsurgical lymphaticovenous anastomotic procedures have been performed to rechannel lymph flow from obstructed lymphatic vessels into the venous system. Limb reduction procedures to resect subcutaneous tissue and excessive skin are performed occasionally in
severe cases of lymphedema to improve mobility

167. You are taking care of a patient who suffers from chronic lymphedema due to recurrent
streptococcal lymphangitis as a child. She finds her leg swelling unsightly and asks about therapeutic
options. All of the following are reasonable therapeutic options for chronic lymphedema EXCEPT:

التوضيح🪄

Secondary lymphedema is an acquired condition that results from
damage to or obstruction of previously normal lymphatic channels. Recurrent episodes of bacterial
lymphangitis, usually caused by streptococci, are a very common cause of lymphedema. The most
common cause of secondary lymphedema worldwide is lymphatic filariasis, affecting approximately 129
million children and adults worldwide and causing lymphedema and elephantiasis in 14 million of these
affected individuals. Other infectious causes include lymphogranuloma venereum and tuberculosis. In
developed countries, the most common secondary cause of lymphedema is surgical excision or
irradiation of axillary and inguinal lymph nodes for treatment of cancers, such as breast, cervical,
endometrial, and prostate cancer, sarcomas, and malignant melanoma. Lymphedema of the arm occurs in
13% of breast cancer patients after axillary node dissection and in 22% after both surgery and
radiotherapy. Lymphedema of the leg affects approximately 15% of patients with cancer after inguinal
lymph node dissection. Tumors, such as prostate cancer and lymphoma, also can infiltrate and obstruct lymphatic vessels. Less common causes include contact dermatitis, rheumatoid arthritis, pregnancy, and self-induced or factitious lymphedema after application of tourniquets.

التوضيح🪄

This is a classic clinical picture for a chronic venous insufficiency with an
active venous ulcer. Symptoms in patients with varicose veins or venous insufficiency, when they occur,
include a dull ache, throbbing or heaviness, or pressure sensation in the legs typically after prolonged
standing; these symptoms usually are relieved with leg elevation. Additional symptoms may include
cramping, burning, pruritus, leg swelling, and skin ulceration. Edema, stasis dermatitis, and skin
ulceration near the ankle may be present if there is superficial venous insufficiency and venous
hypertension. Findings of deep venous insufficiency include increased leg circumference, venous
varicosities, edema, and skin changes. The edema, which is usually pitting, may be confined to the
ankles, extend above the ankles to the knees, or involve the thighs in severe cases. Over time, the edema
may become less pitting and more indurated. Dermatologic findings associated with venous stasis include
hyperpigmentation, erythema, eczema, lipodermatosclerosis, atrophie blanche, and a phlebectasia
corona. Lipodermatosclerosis is the combination of induration, hemosiderin deposition, and
inflammation, and typically occurs in the lower part of the leg just above the ankle. Atrophie blanche is a
white patch of scar tissue, often with focal telangiectasias and a hyperpigmented border; it usually
develops near the medial malleolus. A phlebectasia corona is a fan-shaped pattern of intradermal veins
near the ankle or on the foot. Skin ulceration may occur near the medial and lateral malleoli. A venous
ulcer is often shallow and characterized by an irregular border, a base of granulation tissue, and the
presence of exudate. Ulcers due to arterial insufficiency are typically at the terminal end of a digit, since
that is where flow is most limited. Diabetic ulcers are typically at pressure points such as the sides of the
toes or the ball or heel of the foot. The patient’s report of months of leg discomfort make Bacillus
anthracis infection (cutaneous anthrax) and arachnid envenomation unlikely

165. You are evaluating a 77-year-old woman from Ohio with a history of heart failure with preserved
ejection fraction, diabetes mellitus, and prior left lower extremity deep venous thrombosis status post
a course of anticoagulation. For the past several months, she has complained of a cramping, burning
sensation in her legs. Today she presents for evaluation of a skin ulcer, pictured in Figure V-165. On
examination, you note the skin ulceration over the medial malleolus and a nonpitting woody-type
edema of the bilateral ankles and shins. The skin there is darker as well. This ulcer is most likely due
to which of the following?

التوضيح🪄

Veins in the extremities can be broadly classified as either superficial or
deep. The superficial veins are located between the skin and deep fascia. In the legs, these include the
great and small saphenous veins and their tributaries. The great saphenous vein is the longest vein in the
body. It originates on the medial side of the foot and ascends anterior to the medial malleolus and then
along the medial side of the calf and thigh, and drains into the common femoral vein. The deep veins of
the leg accompany the major arteries. There are usually paired peroneal, anterior tibial, and posterior
tibial veins in the calf, which converge to form the popliteal vein. The popliteal vein ascends in the thigh
as the femoral vein. The confluence of the femoral vein and deep femoral vein forms the common
femoral vein, which ascends in the pelvis as the external iliac and then common iliac vein, which
converges with the contralateral common iliac vein at the inferior vena cava. In the arms, the superficial
veins include the basilic, cephalic, and median cubital veins and their tributaries. The deep veins of the
arms accompany the major arteries and include the radial, ulnar, brachial, axillary, and subclavian veins.
The subclavian vein converges with the internal jugular vein to form the brachiocephalic vein, which
joins the contralateral brachiocephalic vein to form the superior vena cava. Bicuspid valves are present
throughout the venous system to direct the flow of venous blood centrally

التوضيح🪄

Varicose veins are dilated, bulging, tortuous superficial veins, measuring
at least 3 mm in diameter. The estimated prevalence of varicose veins in the United States is
approximately 15% in men and 30% in women. Chronic venous insufficiency is a consequence of
incompetent veins in which there is venous hypertension and extravasation of fluid and blood elements
into the tissue of the limb. It may occur in patients with varicose veins but usually is caused by disease in
the deep veins. Chronic venous insufficiency with edema affects approximately 7.5% of men and 5% of
women, and the prevalence increases with age, ranging from 2% among those less than 50 years old to 10% of those 70 years old. Approximately 20% of patients with chronic venous insufficiency develop
venous ulcers

التوضيح🪄

This patient has a classic presentation of thromboangiitis obliterans, or
Buerger disease. This is an inflammatory occlusive vascular disorder involving small- and medium-size
arteries and veins in the distal upper and lower extremities. Cerebral, visceral, and coronary vessels may
be affected rarely. This disorder develops most frequently in men <40 years of age who are smokers.
The prevalence is higher in Asians and individuals of Eastern European descent. Although the cause of
thromboangiitis obliterans is not known, there is a definite relationship to cigarette smoking in patients
with this disorder. The clinical features of thromboangiitis obliterans often include a triad of claudication
of the affected extremity, Raynaud phenomenon (per the figure), and migratory superficial vein
thrombophlebitis. Claudication usually is confined to the calves and feet or the forearms and hands
because this disorder primarily affects distal vessels. There is no specific treatment except abstention
from tobacco. The prognosis is worse in individuals who continue to smoke, but results are discouraging
even in those who stop smoking. Arterial bypass of the larger vessels may be used in selected instances,
as well as local debridement, depending on the symptoms and severity of ischemia. Antibiotics may be
useful when infection is present. Anticoagulants and glucocorticoids are not helpful. Cilostazol is a
phosphodiesterase inhibitor used for intermittent claudication but has no proven role in thromboangiitis
obliterans. In some cases of advanced disease, amputation may be required.

162. A 32-year-old construction foreman presents with exertional pain in his bilateral forearms and
hands. He smokes one pack of cigarettes per day, but otherwise has no past medical history. He has
an easily palpable brachial pulse but very faint radial and ulnar pulses. A picture of his hand is shown
in Figure V-162. Angiography of his upper extremity reveals smooth tapering segmental lesions in the
small distal arterial vessels. Which of the following treatments has the greatest chance of success?

التوضيح🪄

The patient presents with classic signs of arterial occlusion with limb
pain and physical examination showing pallor and a pulseless, cold leg. She has no risk factors for central
or peripheral atherosclerotic disease; thus, an angiogram would simply confirm the diagnosis of arterial
occlusion, not demonstrate her predisposing condition. In the absence of fever or systemic symptoms,
vasculitis and endocarditis are unlikely sources of arterial embolization. She likely had a paradoxical
embolism in the context of an atrial septal defect, which was the source of her childhood murmur.
Because many of these patients develop pulmonary hypertension with time, she is now at risk for a
paradoxical embolism. Although in this context, arterial emboli frequently originate from venous
thrombus, the thrombi cannot produce a paradoxical embolism in the absence of right-to-left shunt, such
as in a large patent foramen ovale or an atrial septal defect, which can be demonstrated with an
echocardiogram with bubble study.