Uworld post nbme 16 exam with complete
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A 53-year-old man comes to the office with a dull ache in his right shoulder. The
pain is worse with movement and often interferes with his sleep. The patient
cannot recall any traumatic events prior to the start of the pain but did experience
increased discomfort after helping his daughter move into her college dorm room
a week ago. His past medical history includes dyslipidemia and hypertension, for
which he takes the appropriate medications. Physical examination reveals
localized tenderness just below the acromion. The physician asks the patient to
abduct his arms 90 degrees to the side and flex them 30 degrees forward with his
thumbs pointing to the floor. She then applies downward force to his arms. This
maneuver elicits pain in the patient's right shoulder and reveals right-sided
weakness as compared to the left side. A tendon of which of the following
muscles is most likely injured in this patient?
A) deltoid - ANSWER-The rotator cuff consists of the tendons of the
supraspinatus, infraspinatus, teres minor, and subscapularis (SITS) and
contributes to the stability and motion of the glenohumeral joint. During
abduction of the humerus, the supraspinatus initiates movement through the first
10-15 degrees; subsequently, the deltoid provides the primary abductive force
while the supraspinatus provides stability to the joint. Of all the rotator cuff
structures, the supraspinatus tendon is most commonly affected in rotator cuff
syndrome. This tendon is vulnerable to chronic repeated trauma from
impingement between the head of the humerus and the acromion during
abduction. Inflammation and fibrosis can worsen the problem by increasing
friction between the head of the humerus and the acromion, as well as causing
inflammation of the subacromial bursa. On examination, the action of the
supraspinatus can be isolated with the "empty-can" supraspinatus test:
abduction of the humerus in parallel to the axis of the scapula (30 degrees
forward flexion) while in full internal rotation (thumbs pointed to the floor).
A 43-year-old woman comes to the office due to increasing fatigue and weight
gain despite decreased food intake. She states, "I have not been feeling like
myself lately." The patient asks to be referred to a dermatologist as she has
always had "nice" skin that has now become dry. Her hair has been thinning and
,she hopes that a dermatologist can help with that too. Laboratory evaluation
shows high serum TSH, low triiodothyronine (T3), and low thyroxine (T4) levels.
The patient has a family member with fatigue whose energy level increased after
liothyronine (T3) supplementation, and she asks to try this medication.
Administering this therapy would most likely result in which of the following
hormone level changes in this patient?
T3, T4, TSH and reverse T3? - ANSWER-exogenous thyroid hormone is T3 so
thatll increase which will cause TSH levels to decrease leading to decrease in T4
and rT3
TSH from the anterior pituitary stimulates the thyroid to produce thyroxine (T4)
and a small amount of triiodothyronine (T3). T4 is converted in peripheral tissues
to T3 (active form) and reverse T3 (inactive form). TSH secretion is under negative
feedback by thyroid hormone on the hypothalamus and pituitary
A 55-year-old nurse was started on multidrug therapy 3 weeks ago to treat
pulmonary tuberculosis contracted from a former patient. He comes to his
primary care provider due to fatigue and low-grade fever for several days. He also
has had muscle aches and severe joint pain in his elbows, wrists, and knees. The
patient says, "I don't think it's the flu; I had the vaccine months ago." He has no
current respiratory symptoms apart from pleuritic chest pain. The patient has no
other significant past medical or family history. His examination is unremarkable.
Laboratory results are as follows:
Hemoglobin 12.6 g/dL
Platelets120,000/mm3
Leukocytes11,000/mm3 Blood urea nitrogen18 mg/dL
Creatinine0.8 mg/dL
Anti-histone antibodypositive
Anti-nuclear antibodypositive
An abnormality in which of the following metabolic processes most likely
underlies this patient's current condition?
A) Liver hydrolysis
B) Liver hydroxylation
C) - ANSWER-
A 38-year-old man comes to the office due to a 2-month history of an enlarging,
localized swelling on the left foot. Tying his shoelaces too tight leads to localized
pain and numbness in the third and fourth toes. Examination shows a firm,
nontender, well-circumscribed lesion on the dorsum of the foot as shown in the
exhibit. The lesion transilluminates when a penlight is applied to it. Without
treatment, which of the following is most likely to occur in this patient? picture
shows a ganglion cyst
,A) paralysis
B) bloodstream infection
C) Contained crystal aggregation
D) Spontaneous resolution - ANSWER-D
This patient has a ganglion cyst, an outpouching of connective tissue arising
from tendon sheaths, joint structures (eg, joint capsule), or bursae. Clear
mucinous or gelatinous fluid accumulates in the sac, giving rise to a round, well-
circumscribed, firm cyst that transilluminates on penlight examination. Ganglion
cysts are most common on the dorsal and volar wrists, but dorsal foot lesions are
also common. Most ganglion cysts resolve spontaneously and do not require
specific treatment. Cysts that raise cosmetic concerns or cause pain or
paresthesia (due to nerve compression) can be treated with needle aspiration if
desired. However, recurrence is common, and patients may eventually require
surgical excisio
A 28-year-old woman, gravida 3 para 3, comes to the emergency department with
severe abdominal pain in the left lower quadrant and vaginal bleeding. She is
saturating a pad every 3-4 hours. Her last menstrual period was 6 weeks ago.
Past surgical history is significant for 3 cesarean deliveries and permanent
sterilization via a bilateral tubal ligation. A urine pregnancy test is positive, and
an ultrasound shows a 2-cm mass in the left adnexa adjacent to the ovary and a
thickened endometrial stripe. If a uterine curettage is performed, which of the
following findings would be expected in this patient?
A) atypical endometrial cells that form glands.
B)dilated, coiled endometrial glands and vascularized edematous stroma.
C) Enlarged chorionic villi and avascular edematous stroma.
D) An inflammatory endometrial infiltrate
E) Straight, short endometrial glands and compact stroma. - ANSWER-b
Ectopic pregnancy occurs when a fertilized ovum implants outside of the uterus.
The most common site is the ampulla of the fallopian tube, which may appear as
an adnexal mass on ultrasound. Risk factors include tubal pathology, such as
from previous infection or surgery (eg, tubal ligation). Pregnancy after permanent
sterilization is extremely rare, but one-third of cases are ectopic if implantation
occurs. An ectopic pregnancy may become life-threatening as the embryo and
trophoblastic tissue proliferate. This growth will compromise the blood supply to
the surrounding tissues, which can result in rupture and profuse intra-abdominal
bleeding.
A ruptured ectopic pregnancy is managed surgically by removing the pregnancy
and achieving hemostasis. Dilation and curettage of the uterus may be performed
either to stop uterine bleeding or confirm whether the pregnancy is intrauterine or
ectopic.
, In an ectopic pregnancy, the uterine specimen would reveal decidualized
endometrium only, consistent with dilated, coiled endometrial glands and
vascularized edematous stroma. These changes occur in the luteal phase of the
menstrual cycle, under the influence of progesterone, as the endometrium
prepares for implantation. Embryonic and trophoblastic tissue will be absent from
the uterus.
atypical endometrial cells that form glands would suggest endometrial
adenocarcinoma, a malignancy that typically occurs in postmenopausal women
and manifests with vaginal bleeding.
A molar pregnancy or spontaneous abortion may present with vaginal bleeding.
Uterine curettage may show enlarged chorionic villi and avascular edematous
stroma. In contrast, intrauterine chorionic villi are absent in an ectopic
pregnancy.
An inflammatory endometrial infiltrate would suggest endometritis, an infection
of the decidua, which presents with uterine tenderne
A group of researchers is investigating the causative agents responsible for
infections in immunocompromised individuals. Patients with solid-organ
malignancy who have received conventional chemotherapy are enrolled in the
study. Detailed microbiologic data are obtained on any patient who develops
fever during chemotherapy-induced neutropenia. Which of the following types of
pathogens are most likely to be obtained in the majority of these patients?
A) environmental opportunistic infection
B) hospital acquired drug resistant
C) patients own endogenous
D) previously latent reactivated pathogens - ANSWER-C
Systemic chemotherapy targets rapidly dividing cancer cells but often
incidentally damages other rapidly dividing cells in the gastrointestinal tract and
bone marrow, which dramatically increases the risk of infection due to:
Mucositis - Damage to rapidly dividing epithelial cells of the digestive tract
creates breaches in the mucosal barrier that allow endogenous bacterial flora
(commensal organisms) to penetrate and enter the bloodstream. Gram-negative
enteric bacilli, such as Pseudomonas aeruginosa, and gram-positive skin
organisms, such as Staphylococcus epidermidis and S aureus, are most likely to
invade.
Neutropenia - Damage to rapidly dividing granulopoietic cells reduces circulating
neutrophil count. Because neutrophils serve as front-line defense against
bacterial and fungal pathogens, commensal pathogens that penetrate the
