JCAT Mock 4

A 60-year-old man comes to the emergency department because of a cough, shortness of breath, hemoptysis and chest pain for three days. His temperature is 37.5°C (99.5°F) and respiratory rate is 24/min. Laboratory studies show a neutrophil count of 450/µL. He has been self-medicating with amoxicillin and clavulanic acid for the past four days, with no improvement. He was diagnosed with acute leukemia two months ago and is currently following induction chemotherapy treatment. Which of the following is the most likely diagnosis?

A 24-year-old woman is brought to the emergency department following a 2-week history of intermittent fevers. The last time she felt well was 3 weeks ago when she returned from Ethiopia. She then developed a high-grade fever along with dizziness, headaches, and joint pains. Two days after the fever started, she experienced a sudden spike in her temperature followed by an episode of shivering and sweating. The fever then appeared to resolve, but returned again after 6 days, which prompted her to come to the emergency department. Her temperature is 39.9°C (103.8°F), pulse is 90/min, respirations are 20/min, and blood pressure is 135/86 mm Hg. She appears acutely unwell and there is splenomegaly on abdominal examination. A Giemsa stain is positive for spirochetes and labs are normal. Which of the following is the most likely causative organism for this presentation?

A 28-year-old woman, gravida 3 para 1, at 20 weeks gestation comes to the clinic for routine prenatal ultrasonography. She reports no recent changes in her health. The fetal ultrasound shows an amniotic fluid index of ≤ 5 cm (normal 8-18 cm), as well as bilateral deformities of the upper and lower extremities. Further evaluation is most likely to reveal which of the following associated conditions?

A 9-week-old infant is brought to the emergency department for evaluation of somnolence. The parent states that he left the infant sleeping on the couch, but after stepping away for a few minutes to make lunch, he found his baby on the floor next to the couch. Since then, the infant has been sleepy. Vitals are within normal limits. On physical examination, the infant appears lethargic and difficult to arouse. The anterior fontanelle is full and without associated bruising on the scalp. Ocular examination demonstrates bilateral retinal hemorrhages. Which of the following is the most likely diagnosis?

A 32-year old woman, gravida 2, para 1, at 39 weeks’ gestation comes to the emergency department with contractions. She says that she did not have any prenatal care because she does not have health insurance. Upon delivery, the infant appears jaundiced and has marked hepatosplenomegaly. Serum hemoglobin is 11.6 g/dL and serum bilirubin is 8 mg/dL. Direct and indirect Coombs tests are both positive. The mother has never had a blood transfusion. Her previous child was born healthy with no complications. Which of the following is most consistent with the presentation of this disease?

A 32-year-old man presents to the emergency department for evaluation of right-sided back pain. For several weeks, the patient has had worsening, poorly localized right back pain. The pain radiates to the thigh and knee. He does not have a recent history of trauma. Past medical history includes poorly controlled HIV, chronic hepatitis C, and intravenous heroin use. The patient last injected heroin two days ago. Temperature is 37.4°C (99.4°F), blood pressure is 107/67 mmHg, and pulse is 106/min. Pain is elicited with passive extension of the right leg. Physical examination of the back is without focal tenderness, step-offs, or deformities. The patient has an antalgic gait. Neurovascular examination of the bilateral lower extremities is non-contributory, and the patient can void freely. If untreated, this patient is at risk of developing which of the following complications?

A 73-year-old female comes to the clinic with complaints of nausea, epigastric pain, weight loss, and early satiety. She has lost 25 lbs in the last 3 months. Physical examination shows hyperpigmented, velvety axillary skin folds and a palpable upper abdominal mass. Intravenous administration of secretin causes decreased serum gastrin concentration. Stool analysis is negative for H pylori antigen. Stomach biopsy shows mucin filled cells with peripheral nuclei. Which of the following is the most likely diagnosis?

A 45-year-old man comes to the clinic because of purulent abscesses around his mandible. He has been homeless for several years, and says that the lesions have grown steadily in the past months. It is now affecting his ability to swallow. Tissue biopsy shows granulation tissue with rare yellow granules and filaments that are not acid fast. Which of the following organisms is the most likely causative agent?

A 17-year-old boy is brought to the clinic due to academic decline and bizarre behavior for the past 6 months. He used to be a straight-A student, but during the past 2 years, he has been failing exams and repeatedly getting in trouble with teachers. The teachers report that he speaks out of turn, interrupts other students, and makes inappropriate gestures. Vitals are within normal limits. On physical examination, the patient is constantly blinking and clears his throat frequently. Occasionally, the patient points the middle finger at the doctor, and doing so appears to cause the patient distress. The parents are embarrassed and concerned about their son’s demeanor. Which of the following best describes this patient’s behavior?

A 28-year-old woman comes to the emergency department with nausea and vomiting. Over the past few months, the patient has experienced episodes of nausea that occur primarily after eating meals and gradually resolve after a few hours. Tonight, 20 minutes after dinner, the patient experienced a sudden onset of abdominal pain with nausea and regurgitated the majority of her meal; the nausea has persisted. The patient has not had a bowel movement in 3 days. She has a history of type 1 diabetes which was diagnosed at age 12; it has been well managed with a strict insulin regimen delivered by an insulin pump. The patient also takes a multivitamin each evening. The patient’s temperature is 37.0°C (98.6°F), pulse is 80/min, respirations are 16/min, and blood pressure is 115/75 mmHg. Physical examination reveals the patient to be thin and uncomfortable, with a tender epigastrium and mild abdominal distention. Laboratory studies show a normal complete blood count, normal comprehensive metabolic profile, and negative urine β-hCG (human chorionic gonadotropin). Which of the following is the most likely underlying cause of this patient’s symptoms?

A 54-year-old man presents to an infectious disease specialist for follow-up regarding a new diagnosis of hepatitis C. He was diagnosed with chronic hepatitis C several weeks ago after he presented with malaise, fatigue, and elevated liver enzymes. He is a healthcare provider and thinks he may have contracted the disease via an accidental needlestick injury several years ago. He was initially prescribed medications to help treat the disease. His viral titer at today’s visit remains high, and his physician subsequently prescribes an additional medication that works by preventing viral maturation through inhibition of protein synthesis. Which of the following is the most likely side effect of the aforementioned medication used to treat this patient’s condition?

A 45-year-old woman comes to a surgeon after her primary care physician noticed a lump in her neck. A biopsy is performed, and the samples are sent to pathology for analysis, revealing follicular thyroid cancer. The patient is scheduled for a total thyroidectomy. During the operation, a nerve near the superior thyroid artery is injured. Which of the following structures was most likely injured?

A 43-year-old man comes to the emergency department because of a 3-day history of fever, headache, chills, and vomiting. His temperature is 39.8°C (103.6°F), pulse is 110/min, respirations are 16/min, and blood pressure is 137/80 mm Hg. Physical examination shows swollen, red, hot lymph nodes and acral necrosis of the nose, lips, and fingers. Blood cultures show evidence of a gram-negative, non-motile organism with bipolar staining which is catalase positive and oxidase negative. Which of the following virulence factors of the most likely causal organism helps it in immunosuppression?

A 1-day-old boy is seen for his newborn examination. During genital evaluation, his foreskin does not completely encircle the glans. There appear to be two urethral openings, one at the distal tip of the glans, and one located on the ventral surface. The penis appears normal in length. Which of the following is the most appropriate diagnosis?

A 49-year-old woman comes to the office because of intermittent abdominal pain and vomiting for the past two months. She also complains of epigastric pain, eructation, postprandial discomfort, and early satiety. She had surgery for scoliosis two weeks prior to onset of symptoms. Her BMI is 18.2 kg/m². Physical examination shows no abnormalities. Fluoroscopic examination shows dilation of the first and second portions of the duodenum with an abrupt narrowing at the third portion, delayed gastroduodenal emptying, and antiperistaltic waves proximal to the obstruction. Which of the following structures is supplied by the artery that is most likely affected in this patient?

A 1-day old boy is evaluated in the neonatal ICU for preterm birth and low birth weight. The patient was born via uncomplicated spontaneous vaginal delivery to a 35-year-old woman at 34 weeks gestation. The neonate has passed urine and is breastfeeding. He has not passed stool. The mother had a normal pregnancy with regular antenatal care. During her pregnancy, she had two upper respiratory tract infections and a urinary tract infection that was treated. She did not use illicit drugs or consume alcohol during her pregnancy. She did consume caffeinated energy drinks and smoked a pack of cigarettes on the weekends throughout her pregnancy. Temperature is 37.2°C (99°F), blood pressure is 70/30 mmHg, pulse is 120/min, and respiratory rate is 55/min. His weight, length and head circumference are at the 40th percentile for gestational age. Birth weight was 1500g. Abdomen is soft and nontender. Normal heart sounds are heard on cardiovascular auscultation. Which of the following intrauterine processes is most likely responsible for this patient’s clinical findings?

A 2-year-old boy comes to the outpatient clinic because of large amounts of blood in his stool. The mother says he has never had episodes of hematochezia like this prior to a day ago and that he has been eating well. There are no dogs at home, but the mother says he ingested a piece of his older brother’s cheeseburger yesterday. His temperature is 37°C (98.6°F), pulse is 110/min, respirations are 21/min, and blood pressure is 105/75 mm Hg. His skin turgor is normal and his abdominal examination shows no abnormalities. Which of the following is the most likely diagnosis?

A 30-year-old male comes to the physician due to back pain. 2 months ago, he started having back pains which he attributed to the strenuous interval training he attended at that time. The patient discloses morning pain and stiffness which improves after his morning exercise routine. The pain often awakes him at night, but he is able to go back to sleep. On physical examination, pain is reproduced with palpation of the sacroiliac joint and spinal flexion is limited. Estimated erythrocyte sedimentation rate is 75 mm/hr. This patient’s condition is also associated with which of the following?

A 2-day-old infant girl is observed to have several episodes of bilious vomiting while in the nursery. The vomiting is triggered by feeding. She was born full-term to a 38-year-old, gravida 2 para 2, female via vaginal delivery. The pregnancy was complicated by polyhydramnios. The patient’s vitals are notable for hypotension and tachycardia. Examination of the skull reveals sunken anterior and posterior fontanelles. The patient is also observed to have upslanted palpebral fissure and prominent epicanthal folds. A single transverse palmar crease is noted on the bilateral hands. The patient has a scaphoid abdomen. Digital rectal examination reveals normal rectal tone and no expulsion of gas or stool. Which of the following best describes the pathophysiology of this patient’s condition?

A 27-year-old woman comes to the emergency department because intense abdominal pain for 2 hours. When asked to describe the pain, she states it has been severe and constant. She states it began subtly in the right iliac fossa. Examination shows a pale appearing patient. Her temperature is 37.8°C (99°F), pulse is 112/min, respirations are 23/min, and blood pressure is 101/68 mm Hg. Abdominal examination causes severe discomfort, and there are clear signals of peritonism. There is also a palpable mass in the right iliac fossa. Which of the following is the most likely diagnosis?

A 24-year-old woman comes to the clinic for evaluation of painless swelling around the right side of the labia minora. The patient is in good health and does not use tobacco, alcohol, or illicit substances. Two-years ago, the patient was treated for a Chlamydia trachomatis infection. The patient’s temperature is 37.0°C (98.6°F), pulse is 75/min, and blood pressure is 115/70 mmHg. Examination of the vulva reveals a 1 cm area of swelling and mild erythema on the posterior aspect of the labia majora. The affected area is located at the eight o’clock position with respect to the vaginal orifice. Which of the following structures is most likely affected in this patient’s condition?

A 17-year-old boy comes into the office for a physical examination for football tryouts. He has a family history of diabetes and hypertension. He explains that he has been feeling fatigued and has suffered being overweight the majority of his life. Physical examination shows abdominal swelling, enlarged breasts, and palmar erythema on hands. The spleen is palpable. Lab studies show elevated aspartate aminotransferase (AST) and alanine aminotransferase (ALT). ALT concentrations are greater than AST concentration.  Which of the following is most likely the diagnosis?

A 39-year-old woman is brought to the clinic by her partner for involuntary movements of the hands and face. The symptoms began 6-months ago and have progressively worsened. In addition, she has been experiencing personality changes over the past 2 months. According to the partner, the patient has withdrawn from activities she previously enjoyed, such as attending weekly book clubs with her friends. Moreover, the patient has had a decreased appetite and is sleeping less than before. Past medical history is noncontributory. Her father experienced similar motor symptoms and commited suicide at the age of 47. In the office, her temperature is 37.0°C (98.6°F), pulse is 78/min, blood pressure is 126/80 mmHg, and respirations are 14/min. Deep tendon reflexes are 3+ bilaterally in the upper and lower extremities. During the physical exam, the patient makes repeated writhing movements using the fingers and arms. Imaging of the head is ordered. MRI of the brain is most likely to demonstrate which of the following?

A 64-year-old man comes to the physician for evaluation of dysarthria and dysphagia. The patient’s symptoms started three months ago. Past medical history includes type II diabetes mellitus and hypertension, both poorly controlled. Current medications include metformin, glyburide, losartan, and atorvastatin. He has a 40-pack-year smoking history. Temperature is 37.5°C (99.5°F), blood pressure is 162/89 mmHg, and pulse is 80/min. Examination of the head and neck reveals atrophy and fasciculations of the tongue. Rightward deviation of the tongue is noted when the patient is asked to protrude the tongue. He has no sensory or motor abnormalities in other parts of the face or the body. Further evaluation of this patient’s clinical history will most likely reveal the following?

A 67-year-old woman comes to the office because of pain and strange sensations in her left arm. The symptoms have been worsening for the past two months. She has hypertension, diabetes mellitus type II, and gout. She has been receiving hemodialysis from a left upper arm arteriovenous fistula for the past year due to end-stage renal disease. Physical examination shows dry, grey patches on her left fingertips and ulcerations at the second finger. Which of the following is most likely an additional finding in this patient’s left arm?

A 50-year-old man comes to the clinic due to difficulty hearing for the past 2 months. He describes difficulty hearing mainly on the left side, and he notes a constant “whoosh” sound in the same ear. The patient reports feeling unsteady lately but denies any dizziness or spinning sensations. Medical history is significant for hyperlipidemia and hypertension. Medications include furosemide and lovastatin. Vital signs are within normal limits. Physical examination shows that the patient does not respond when the physician whispers in the left ear. A tuning fork placed on the mastoid bone shows that air conduction is greater than bone conduction bilaterally. When the fork is placed on the top of the head, the sound localizes to the right ear. Which of the following is the most likely diagnosis?

A 70-year-old man comes to the clinic for a follow up after his diagnosis with heart failure two weeks ago. It is discovered that he has severe hemodynamic compromise with low cardiac output. Milrinone is considered for treatment. Milrinone is known for its ability to relax vascular smooth muscle and therefore cause vasodilation through its inhibition of phosphodiesterase-3, thus decreasing the degradation of cAMP. Given this mechanism of action, which of the following other effects would be expected?

A 28-year-old woman, gravida 1 para 1, presents to the emergency department with complaints of lower abdominal pain and foul-smelling vaginal discharge. She gave birth to a healthy female newborn 2 days ago. Vaginal delivery was converted into emergency cesarean section due to obstructed labor, and the placenta was removed manually. Past medical history is significant for pre-gestational diabetes mellitus type II as well as Neisseria gonorrhoeae cervicitis when the patient was 19, for which she was treated appropriately. Temperature is 101.4°F (38.5 °C), pulse is 100/minute, respirations are 19/minute, and blood pressure is 100/60 mmHg. BMI is 33 kg/m2. On physical examination, there is mild peri-incisional tenderness, minimal discharge at the surgical site, and no erythema or edema around the incision site. Foul-smelling greenish-yellow lochia is observed in the vaginal vault. Bimanual examination shows cervical motion and uterine tenderness. Complete blood profile shows hemoglobin of 12 g/dL and leukocyte count of 18,000/mm3. Which of the following is the most likely diagnosis?

A 72-year-old man comes to the office because of intermittent fatigue and weakness, especially in the evenings. He says that his head sometimes feels too heavy for his neck, and it is even difficult for him to smile. Physical examination shows a drooping left eyelid that improves with administration of edrophonium. Which of the following is the most likely underlying mechanism of this patient’s condition?

A 55-year-old man comes to the emergency department for evaluation of sudden onset palpitations and lightheadedness. His symptoms began one hour ago while working in his garden. He reports similar episodes over the past several months that self-resolved. Temperature is 37.0°C (98.6°F), pulse is 110/min irregularly irregular, respirations are 20/min, and blood pressure is 135/85 mmHg. On physical examination, a rumbling mid-diastolic murmur is heard over the cardiac apex when the patient lies in the left lateral decubitus position. Further history will most likely reveal which of the following?

A 51-year old woman comes to the office because of diplopia and ataxia. She also reports some minor tingling and weakness of her legs which seems to progress upward. She reports having flulike symptoms in the past month which ceased three weeks ago. Physical examination shows restricted extraocular movements as well as an absence of reflexes on her upper and lower extremities. She has impaired light touch sensation and proprioception in her legs. Her gait is severely ataxic, and she cannot walk without a cane. A lumbar puncture shows an elevated cerebrospinal fluid (CSF) protein levels without any cells present. Which of the following diagnoses most likely accounts for her symptoms?

A 3-year-old boy is brought to the office by his parents for the evaluation of frequent falls. The parents report that the patient has had difficulty running and walking up stairs for the past year, and now they have noticed numerous unprovoked falls. Family history is unremarkable. Vitals are within normal limits. Physical examination shows enlarged and nontender calves bilaterally. When asked to rise from the floor, the boy uses hand support to push himself to an upright position. Serum creatinine kinase is 14,000 U/L. Molecular genetic testing reveals a large defective muscle protein due to the loss of 508 amino acid residues. Based on the suspected diagnosis, which of the following mutations is most likely involved in the pathogenesis of this patient’s condition?

A 4-year-old boy is brought to the office by his parents for evaluation of leg pain. He has been experiencing progressive leg pain over the past 3 months that is worse with activity. The parents report that the patient also has difficulty running and walking up stairs for the past year, and they have noticed that he always “walks on his toes.” He was adopted as an infant, and family history is unknown. Vitals are within normal limits. Height, weight and head circumference is at 20th percentile, similar to previous visits. Physical examination shows bilateral calf hypertrophy and thin, atrophied thighs. Extremities are nontender to palpation. When asked to rise from the floor the boy uses hand support to push himself to an upright position. He has a waddling gait. Which of the following laboratory tests will most likely help to develop a diagnosis?

A 57-year-old woman presents to her primary care physician with malaise and intermittent fevers over the past several weeks. She reports she was recently treated for a urinary tract infection, but her symptoms never completely improved. Her past medical history is significant for recurrent nephrolithiasis and type 2 diabetes mellitus. Her temperature is 38°C (100.4°F), pulse is 82/min, respirations are 16/min, blood pressure is 157/64 mmHg, and oxygen saturation is 99% on room air. Physical examination shows left-sided costovertebral angle tenderness on palpation. If a biopsy of the kidney was to be performed, which of the following findings is most likely to be demonstrated on histologic analysis?

A 23-year-old woman with a history of anxiety comes to the office with abdominal pain and altered bowel habit. The patient has a 4-month history of cramping abdominal pain and fluctuations between diarrhea and constipation. Physical examination shows no abnormalities. Her hemoglobin level is 12.5 grams/dL and celiac disease serology is negative. Which of the following would be considered an alarm symptom in this patient?

A 29-year-old woman comes to the physician complaining of recurrent bloating and diarrhea over the past 2 months. She has bulky and foul-smelling diarrhea that is often difficult to flush. The patient had a Roux-en-Y reconstruction 5 years ago for morbid obesity that was refractory to diet and lifestyle modifications. Since then, she has lost 45-lbs, which has significantly improved her daily life. Physical examination reveals conjunctival pallor. Laboratory studies demonstrate a hemoglobin of 10.3 g/dL and mean corpuscular volume (MCV) of 101 µm3. Serum electrolytes are normal. Stool analysis shows no occult blood and stool culture is negative. The patient is asked to ingest 25 g of D-xylose following an overnight fast. Urine concentration of D-xylose after several hours is 3.0 g (normal ≥4.5 g). The physician prescribes her oral antibiotics, and the test is repeated after 2 weeks. Subsequent urine concentration is 9.2 g. Which of the following is the most likely cause of this patient’s symptoms?

A 26-year-old woman, gravida 3, para 0, at 18 weeks’ gestation comes to the emergency department because of a large amount of vaginal discharge 30 minutes ago. She was sitting on her couch when the clear fluid began to rush out of her vagina. It did not have an odor. She reports feeling well lately, has had no sick contacts, and has not been sexually active. Her medical history includes two previous miscarriages in the second trimester. Her temperature is 37.0°C (98.6°F), pulse is 84/min, respirations are 16/min, and blood pressure is 132/84 mm Hg. She is not experiencing any pain. Pelvic examination shows a 3cm cervical dilation with 50% effacement. She goes into labor and delivers the previable infant within 2 hours. Three months later, a transvaginal ultrasound shows a short cervical length. Which of the following is the most likely diagnosis?

A 22-year-old woman comes to the clinic to evaluate perianal pruritus and genital lesions. Two months ago, she was diagnosed with acute cervicitis due to Neisseria gonorrhoeae and treated with outpatient antibiotics. She is sexually active and began a monogamous relationship with a new male partner three months ago. They use condoms inconsistently. The patient has had five sexual partners in her lifetime.  Temperature is 37.0°C (98.6°F), pulse is 90/min, respirations are 20/min, and blood pressure is 120/75 mmHg. The abdomen is soft and nontender. External genital examination reveals several smooth, verrucous, skin-colored lesions over the labia majora and minora. Cervical motion tenderness is absent on bimanual examination. Which of the following describes the microorganism most likely responsible for this patient’s symptoms?

A 64-year-old man comes to the emergency department because of severe central chest pain for 2 hours. He says the pain is heavy in nature and radiates to his jaw. He has a history of uncontrolled hypertension and type 2 diabetes mellitus. His temperature is 36.8°C (98°F), pulse is 97/min, respirations are 18/min, and blood pressure is 163/91 mm Hg. Cardiovascular auscultation shows a holosystolic murmur that seems loudest at the apex. ECG shows ST-elevation in leads V₂, V₃, and V₄. Which of the following will most likely occur as a result of this pathology?

A 35-year-old woman presents to the clinic because of increasing abdominal girth and constipation for the past 3 months. She reports no associated nausea, vomiting, abdominal pain or abnormal vaginal bleeding. Her last menstrual period was 3 weeks ago. She is sexually active with one male partner and denies any pain during intercourse. Past medical and surgical history is unremarkable. Current medications include combined oral contraceptives and multivitamins. Vitals are within normal limits. Physical examination shows an enlarged, mobile, nontender, irregular uterus corresponding to 12-week sized gestation. Which of the following is the most likely diagnosis in this patient?

A 34-year-old Caucasian woman presents unwell to the emergency department because she has severe epigastric pain radiating to her back over the past hour. This pain came on suddenly, has gradually increased in severity, and is associated with a sensation of nausea. She has a history of biliary colic with confirmed gallstones, but states that this episode “feels different” to her usual colic. She has a BMI of 33kg/m². Her temperature is 36.8°C (98°F), pulse is 87/min, respirations are 18/min, and blood pressure is 117/78 mm Hg. Which of the following biochemical tests has the highest positive predictive value for determining a biliary etiology for this patient’s symptoms?

A 22-year-old woman comes to the office because of painful urination for 2 days. She states that in addition to experiencing pain when passing urine, she feels that the urge to pass urine comes on very suddenly. She is sexually active with a new partner, and uses no form of contraception, however says that she has not experienced any vaginal itch or discharge. Her medical history is noncontributory. Family history includes type II diabetes mellitus in both parents. Her temperature is 36.5°C (99°F); pulse is 72/min; respirations are 15/min, and blood pressure is 117/78 mm Hg. Abdominal examination shows only suprapubic tenderness to palpation. Which of the following is the most likely diagnosis?

A 44-year-old man comes to the office because of persistent dyspepsia. The patient has been taking a high dose of omeprazole for two months with some improvement in the symptoms, but he still complains of mild, burning epigastric pain alleviated by eating. As a result, he has gained 6.8-kg (15-lb) over this period of time. In addition, he complains of foul smelling, non-bloody diarrhea 1-2 times daily. Temperature is 37°C (98.6°F), pulse is 86/min, respirations are 16/min, and blood pressure is 142/62 mmHg. Physical examination is unremarkable. The patient undergoes esophagogastroduodenoscopy, which reveals multiple ulcers in the proximal and distal duodenum. Biopsies of the ulcers are negative for Helicobacter pylori. Which of the following findings is diagnostic of this patient’s underlying condition?

A 70-year-old man comes to the emergency department because of high fever, cough, and muscle aches. He has a history of chronic obstructive pulmonary disease, for which he was recently spent one week in the hospital. A chest X-ray is performed and shows consolidation in the bottom portion of the left lung. A sputum culture is performed and stained positive with silver. Which of the following is the most likely cause of this patient’s illness?

A 6-year-old boy comes to the office because his parents have noticed that he is unable to keep up with his friends at the playground. He tires easily and points to his thighs when asked if anything hurts him. He has a history of myoclonic epilepsy. A muscle biopsy is performed and shows ragged red muscle fibers. Which of the following is the most likely diagnosis?

A human cadaveric model is being studied to better understand the anatomic distribution and innervation of muscles in the upper extremity, chest, and back. A nerve root is stimulated with an electrical impulse, which results primarily in the contraction of the lumbricals and interossei of the hand. Which of the following accurately reflects the nerve root(s) being tested in this experiment?

A 42-year-old female comes to the clinic with 2 weeks cold intolerance, weight gain, constipation, and a neck mass. She also says there was a period 6 months ago where she was losing weight without even trying, so she was surprised when she began gaining it all back. She denies any fever or neck pain. Laboratory serum studies show anti-microsomal antibodies. Biopsy of the mass shows pink cells and lymphoid aggregates with germinal centers. Which of the following is the most likely diagnosis?

A woman presents to the physician because of pain and swelling in the right breast. The woman has been lactating for 2-weeks. Physical examination reveals tenderness, erythema, and swelling in the right breast and enlarged, tender right axillary lymph nodes. Which of the following best describes the lymphatic drainage pathway from the inflamed lymph nodes?