543 Review Part 1

An 11-year-old boy is brought to the emergency department 30 minutes after he had a cardiac arrest. He was playing soccer with his friends at school when he suddenly collapsed on the field. A teacher who witnessed the incident successfully performed cardiopulmonary resuscitation and called the ambulance. The patient has no history of serious illness. His uncle died of sudden cardiac death at the age of 35. On arrival, he appears exhausted. His pulse is 82/min and blood pressure is 118/75 mm Hg. He is oriented to person, place, and time. Cardiac examination shows a grade 3/6 crescendo-decrescendo systolic murmur that is heard best at the apex and left lower sternal border, and an S4 gallop. Which of the following is the most appropriate treatment to reduce the risk of premature death in this patient?

AICD placement

A 14-year-old boy is brought to the physician because of fever, malaise, and severe right knee joint pain and swelling for 3 days. He has also had episodes of abdominal pain and epistaxis during this period. Five days ago, he had swelling and pain in his left ankle joint which has since resolved. He reports having a sore throat 3 weeks ago while he was camping in the woods, for which he received symptomatic treatment. His immunizations are up-to-date. His temperature is 38.7°C (101.6°F), pulse is 119/min, and blood pressure is 90/60 mm Hg. Examination shows a swollen, tender right knee; range of motion is limited. There are painless 3- to 4-mm nodules over the elbow. Cardiopulmonary examination is normal. His hemoglobin concentration is 12.3 g/dL, leukocyte count is 11,800/mm3, and erythrocyte sedimentation rate is 58 mm/h. Arthrocentesis of the right knee joint yields clear, straw-colored fluid; no organisms are identified on Gram stain. Analysis of the synovial fluid shows a leukocyte count of 1,350/mm3 with 17% neutrophils. Which of the following is the most likely diagnosis?

Acute rheumatic fever

A 1-month-old boy is brought to the physician because of a 5-day history of generalized fatigue and multiple episodes of vomiting which is most pronounced after formula feeding. His vomiting progressed from 2-3 episodes on the first day to 6-8 episodes at present. The vomitus is whitish in color. The mother reports that he has been very hungry after each episode of vomiting. The patient was born at 38 weeks' gestation and weighed 3100 g (6 lb 13 oz); he currently weighs 3500 g (7 lb 11 oz). He appears irritable. His temperature is 37.1°C (98.8°F), pulse is 130/min, respirations are 43/min, and blood pressure is 74/36 mm Hg. Examination shows dry mucous membranes. The abdomen is soft and not distended. There is a round mass palpable in the epigastric region. The liver is palpated 1 cm below the right costal margin. Laboratory studies show: A urinalysis shows a decreased pH. Which of the following is the most appropriate next step in the management of this patient?

Administer IV 0.9% NaCl and replace electrolytes

A 3-year-old girl is brought to the physician because she has had 1-2 bowel movements a week for 4 weeks. Her mother has noticed the child straining and that the stools she passed were hard. The child has been attending a daycare center for 2 months and she has recently begun toilet training. She was born at term and the neonatal period was uncomplicated. Her 6-year-old brother has Hirschsprung's disease. She is at 50th percentile for height and weight. Vital signs are within normal limits. The abdomen is soft and nontender. Rectal examination shows a large and hard fecal mass. The remainder of the examination shows no abnormalities. Which of the following is the most appropriate next step in management?

Administer polyethylene glycol

Which of the following is the most accurate description of Eisenmenger's syndrome a) Due to lack or aorticopulmonary septum formation b) A right to left shunt becomes a left to right shunt due to build-up of pressure on the left side of the heart c) Due to failure of the aorticopulmonary septum to spiral d) An initial left to right shunt becomes a right to left shunt due to increased pulmonary blood flow and eventual right ventricular hypertrophy?

An initial left to right shunt becomes a right to left shunt due to increased pulmonary blood flow and eventual right ventricular hypertrophy

A healthy 2-week-old girl has yellow discharge from her left eye. Her mother had early prenatal care, the baby was delivered vaginally, and she was discharged at 48 hours of life. Within the first few days of life, the mother noted that the baby had increased tear production in her left eye, which now has yellow discharge. She has red reflexes bilaterally, her pupils are equal and reactive to light, and she has no scleral injection. She has left-sided mucous ocular discharge. The next step is to:

Begin a course of topical antimicrobial treatment and nasolacrimal massage and warm water cleansing.

A 770-g (1-lb 11-oz) female newborn delivered at 28 weeks' gestation develops rapid breathing, grunting, cyanosis, and subcostal retractions shortly after birth. Her mother did not receive any prenatal care. Breath sounds are decreased over both lung fields. An x-ray of the chest shows diffuse fine, reticular densities bilaterally. Antenatal administration of which of the following drugs would most likely have prevented this infant's current condition? A. Epinephrine B. Betamethasone C. Thyrotropin-releasing hormone D. Oxytocin E. Insulin F. Indomethacin

Betamethasone

A 6-year-old boy is brought to the emergency department with a mild fever for the past week. He has also had generalized weakness and fatigue for the past month. He has been complaining of diffuse pain in his legs and arms. He has a history of Down syndrome with surgical repair of a congenital atrial septal defect as an infant. His temperature is 38.0° C (100.4° F), pulse is 85/min, respirations are 16/min, and blood pressure is 90/60 mm Hg. He has enlarged cervical lymph nodes bilaterally that are nontender to palpation. He is uncooperative for the rest of the examination. Laboratory studies show: Which of the following is best for a definitive diagnosis of the suspected condition?

Bone marrow biopsy

A 4-month-old child is brought in by her mother with a three-day history of poor feeding, shortness of breath, cough and fever. You examine the child who has a RR 45, sats 98%, Temp 37.8. Chest auscultation reveals bilateral crepitations, occasional scattered wheeze and increased work of breathing. What is the most likely diagnosis based on your clinical findings?

Bronchiolitis

An 11-year-old boy who recently emigrated from Nigeria is brought to the physician for evaluation of jaw swelling. He has no history of serious illness and takes no medications. Examination shows a 5-cm solid mass located above the right mandible and significant cervical lymphadenopathy. Serology for Epstein-Barr virus is positive. Which of the following is the most likely diagnosis?

Burkitts lymphoma

A 2-year-old boy is brought to the physician for generalized fatigue and multiple episodes of abdominal pain and vomiting for the past week. His last bowel movement was 4 days ago. He has been having behavioral problems at home for the past few weeks as well. He can walk up stairs with support and build a tower of 3 blocks. He cannot use a fork. He does not follow simple instructions and speaks in single words. His family emigrated from Bangladesh 6 months ago. He is at the 40th percentile for height and weight. His temperature is 37°C (98.6°F), pulse is 115/min, and blood pressure is 84/45 mm Hg. Examination shows pale conjunctivae and gingival hyperpigmentation. His hemoglobin concentration is 10.1 g/dL, mean corpuscular volume is 68 μm3, and mean corpuscular hemoglobin is 24.5 pg/cell. The patient is most likely going to benefit from administration of which of the following?

Calcium disodium edetate chelation

Samantha Hayes, 18, has scheduled a GP consultation to discuss an itchy vesicular rash on her forearms. Whilst reading her notes, you learn that she was in the lowest growth decile as a child, and has recurrent bouts of diarrhea, queried gastroenteritis, over the past year. She currently takes iron tablets and vitamin D. What is the most likely diagnosis?

Celiac disease

A 3-year-old boy is brought to the physician because of a 1-day history of abdominal pain and frequent urination. His mother reports that the patient has wet his bed overnight and that his urine smelled odd this morning. He has been toilet trained for 4 months and has had very few accidents since then. His last bowel movement was 3 days ago. He was born at term after a normal gestation and has reached all developmental milestones. His parents divorced 4 months ago and the patient's father has moved away. The patient began preschool 6 weeks ago. During this period, he has had two upper respiratory infections that resolved without treatment. His 12-year-old brother has type 1 diabetes mellitus. Vital signs are within normal limits. Physical examination of the abdomen shows mild suprapubic tenderness. Urine dipstick is positive for leukocyte esterase, nitrite, and blood; urinalysis shows white blood cells and gram-negative rods. Which of the following is the most likely predisposing factor for this patient's condition?

Constipation

A female newborn delivered at 38 weeks' gestation is evaluated for abdominal distention and bilious vomiting 24 hours after delivery. The pregnancy and delivery were uncomplicated. She appears lethargic and her fontanelles are sunken. An x-ray of the abdomen is shown. This infant most likely has a congenital obstruction affecting which of the following anatomic structures? (double bubble)

Duodenum

A mother brings her 5-year-old boy. You notice that they have requested a translator as they are visiting from Japan. The mother explains, via the translator, that the child has been unwell with a fever for nearly a week now. She wanted to bring him sooner but it took time to book the translator. He is just not himself and seems very under the weather. On examination, he has red eyes, dry, cracked lips and a rash on his hands and feet. He also has cervical lymphadenopathy. What is the most important investigation to rule out a serious complication of this condition?

Echocardiogram

A 5-week-old male infant is brought to the physician by his mother because of a 4-day history of recurrent nonbilious vomiting after feeding. He was born at 36 weeks' gestation via spontaneous vaginal delivery. Vital signs are within normal limits. Physical examination shows a 2-cm epigastric mass. Further diagnostic evaluation of this patient is most likely to show which of the following?

Elongated and thickened pylorus on abdominal ultrasound

A mother brings her 6-year-old son to the GP due to bed wetting. She states he has wet the bed infrequently over the last few years but in the past month, this has become much more frequent. He has never been dry for more than 5 nights. The mother explains she has been following advice on forums including reducing her son's caffeine intake, taking him to the toilet before bed and providing rewards for dry nights. Despite all of these efforts, the bedwetting has continued at the same frequency. What is the next appropriate management option?

Enuresis alarm

A 4-year-old girl is brought to the physician because of pallor and rash for 2 days. She had a 4-day history of diarrhea and vomiting that subsided two days ago. One month ago, she had a 3-day episode of high fever, followed by a rash with bright red discoloration over her cheeks for two days before subsiding without treatment. Her vaccinations are up-to-date. She appears pale and irritable. Her vital signs are within normal limits. Examination shows petechiae on her trunk and extremities. Abdominal examination shows diffuse abdominal tenderness with hyperactive bowel sounds. The remainder of the examination shows no abnormalities. Laboratory studies show: A peripheral blood smear shows schistocytes. Which of the following is the most likely underlying cause of these findings?

Escherichia coli infection

A 13-year-old boy is brought to the physician because of progressive left leg pain for 2 months, which has started to interfere with his sleep. His mother has been giving him ibuprofen at night for "growing pains," but his symptoms have not improved. One week before the pain started, the patient was hit in the thigh by a baseball, which caused his leg to become red and swollen for several days. Vital signs are within normal limits. Examination shows marked tenderness along the left mid-femur. His gait is normal. Laboratory studies show a leukocyte count of 21,000/mm3 and an ESR of 68 mm/h. An x-ray of the left lower extremity shows multiple lytic lesions in the middle third of the femur, and the surrounding cortex is covered by several layers of new bone. A biopsy of the left femur shows small round blue cells. Which of the following is the most likely diagnosis?

Ewing's sarcoma

A 2550-g (5 lb 10 oz) female newborn is delivered at term to a 27-year-old woman, gravida 1, para 1. Labor and delivery were uncomplicated but the mother did not receive prenatal care. Examination of the newborn shows hypotonia in the lower extremities and a red, fleshy swelling without overlying skin in the lumbosacral region. Clear yellow fluid leaks from the superior margin of the swelling. Ultrasonography of the swelling shows a fluid-filled sac containing herniated neural tissue. Which of the following best explains the pathogenesis of this patient's condition?

Failure of posterior neuropore closure

A 6-year-old boy presented to the emergency room with his mother, complaining of severe left knee pain after falling down while playing soccer. On examination, the knee was swollen, warm to touch, and range of motion was limited. Investigations reveal a normal full blood count. Coagulation studies are within the normal range, other than APTT which is increased. His mother mentions that her son had prolonged bleeding after a recent dental extraction. What is the most likely diagnosis?

Hemophilia A-Factor VIII Deficiency

A 15-year-old girl is brought to the physician because of a 8-month history of fatigue, intermittent postprandial abdominal bloating and discomfort, foul-smelling, watery diarrhea, and a 7-kg (15-lb) weight loss. She developed a pruritic rash on her knees 3 days ago. Physical examination shows several tense, excoriated vesicles on the knees bilaterally. The abdomen is soft and nontender. Her hemoglobin concentration is 8.2 g/dL and mean corpuscular volume is 76 μm3. Further evaluation of this patient is most likely to show which of the following findings?

IgA tissue transglutaminase antibodies

A 2-week-old infant is brought to the emergency room because of 4 episodes of bilious vomiting and inconsolable crying for the past 3 hours. Abdominal examination shows no abnormalities. An upper GI contrast series shows the duodenojejunal junction to the right of the vertebral midline; an air-filled cecum is noted in the right upper quadrant. Which of the following is the most likely cause of this patient's condition?

Incomplete intestinal rotation

A 4-year-old boy is brought to the physician by his parents because of fever and mild abdominal pain for 7 days. His parents report that he developed a rash 2 days ago. He has had no diarrhea or vomiting. Four weeks ago, he returned from a camping trip to Colorado with his family. His immunization records are unavailable. His temperature is 39.4°C (102.9°F), pulse is 111/min, respirations are 27/min, and blood pressure is 96/65 mm Hg. Examination shows bilateral conjunctival injections and fissures on his lower lips. The pharynx is erythematous. There is tender cervical lymphadenopathy. The hands and feet appear edematous. A macular morbilliform rash is present over the trunk. Bilateral knee joints are swollen and tender; range of motion is limited by pain. Which of the following is the most appropriate treatment for this patient's condition?

Intravenous immunoglobulin

A 4-year-old boy is brought in by his worried parents. The boy has had a fever, cough and runny nose for the past few days and this morning has developed a rash which began on his head and neck and has now spread to his chest and arms. His parents believe that vaccines cause harm and as a result, they have not immunized their child. The appearance of his mouth (red papules) on examination is shown in the picture.

Isolation

Toby Robertson is a 15-year-old boy who attends the GP practice with his mother who is concerned that he appears to be developing breasts. He has no significant past medical history but he does receive support at school for learning difficulties. Findings on examination include: Tall stature Elongated arms and legs Reduced facial and body hair Wide hips Gynecomastia Small testicles Which of the following is the most likely diagnosis?

Klinefelter's syndrome

A 6-month-old girl is brought to the physician because of a 2-month history of noisy breathing. Her parents state that her breathing has become progressively louder during this time. It is worse when she is lying on her back, feeding, and crying, and it improves when she is placed on her abdomen. Her mother also mentions that the girl has been regurgitating milk more than usual for the past few weeks. She was born at term and has been otherwise healthy. Her immunizations are up-to-date. Her diet consists exclusively of formula milk. She is at the 65th percentile for length and weight. Vital signs are within normal limits. Examination discloses inspiratory stridor. Which of the following is the most likely diagnosis?

Laryngomalacia

A neonate is born and shortly becomes acutely tachypneic with a hypercyanotic episode, appearing to be entering shock. The patient is positive for trisomy 21 and emergent echocardiography reveals tetralogy of Fallot. Which of the following morphological changes would you not expect this patient's heart to have?

Left ventricular hypertrophy

Kevin, a 5-year-old boy, presents to the GP surgery with a limp. His mother says that Kevin has been complaining of pain in the right hip and knee. She has also noticed some swelling around the hip on the right. Kevin and his mother deny any falls or other trauma. On examination, Kevin seems well but he walks with an antalgic gait. There is limited abduction and internal rotation of the right hip in both flexion and extension. The hip is swollen but not hot or red. What is the most likely diagnosis?

Legg-Calve-Perthes Disease

You are working in the ED on a cold, wet afternoon in October. You are asked to see an 18-month-old child with a barking cough and added breathing sounds. Which of the following would cause you to refer him to the hospital for observation?

Mild stridor when calm and at rest

A 3-year-old boy is brought into A&E by his parents who feel his face is swollen. They describe progressive facial swelling over the past 4 days. The child is otherwise well and has no significant past medical history. On examination, you note facial and limb oedema. Vital signs are all within normal limits. A urinalysis shows proteinuria (++++), but nil else. What is the most likely diagnosis?

Minimal change disease

A 1-week-old preterm, formula-fed infant, presents with a distended abdomen and bilious vomiting. Hemoccult positive. The X-ray shows dilated loops of large bowel. Which of the following is the most likely diagnosis?

Necrotizing enterocolitis

An 18-month-old boy presents at 2 am to the Emergency Department with a cough and noisy breathing. His mother tells you that he has been not quite himself for 2 days with a presumed 'cold'. However, tonight he woke up with a 'barking cough' and now his breathing sounds more noisy than usual. He is normally well with no medical problems and no regular medications. His mother denies that he has any known allergies. On examination, you see a child that is playful and interactive. He, however, has an inspiratory stridor with some accessory muscle use. His saturations are 99% on room air. He responds extremely well to oral dexamethasone and is observed for a period within the Emergency Department. Prior to discharge, his mother asks you about the cause of his condition. Which of the following is the most common underlying aetiology?

Parainfluenza Virus

A 1-year-old boy is brought to the physician because of irritability and poor feeding that began 2 days ago. His mother reports that he has been crying more than usual during this period. He refused to eat his breakfast that morning and has not taken in any food or water since that time. He has not vomited. When changing the boy's diapers this morning, the mother noticed his urine had a strong smell and pink color. He has not passed urine since then. He was born at term and has been healthy. He appears ill. His temperature is 36.8°C (98.2°F), pulse is 116/min, and blood pressure is 98/54 mm Hg. The boy cries when the lower abdomen is palpated. Which of the following is the most appropriate next step in management?

Perform transurethral catheterization

A 9-year-old girl presents to A&E with hematuria which started yesterday evening. The parents describe noticing blood-stained dark brown urine in the toilet. The parents say the child has been more tired than usual but has been otherwise well, with the only recent illness of note being a throat infection a month ago. The child has no past medical history and takes no regular medication. On examination the child appears lethargic however there are no clinical signs of significance. Bedside urinalysis shows proteinuria (++) and hematuria (+++). Vital signs are as follows: BP: 140/80 mmHg Pulse: 80 bpm Respiratory rate: 14 breaths per minute Oxygen saturation: 98% Temperature: 37.5 oC (99.5) Which of the following is the most likely diagnosis?

Post-infectious glomerulonephritis

A neonate, born at term 2 days ago presents with cyanosis and respiratory distress. Your consultant performs an echocardiogram and diagnoses tricuspid atresia. What is the first and most urgent intervention for this child?

Prostaglandin infusion

Henry, a 7-year-old boy with a diagnosis of cystic fibrosis presents with worsening of his usual symptoms. He is febrile, and although he has difficulty expectorating, you manage to obtain a sputum sample to send to the lab. What is the most likely organism?

Pseudomonas aeruginosa

A 6-week-old male infant is brought by his parents to the ER with complaints of projectile vomiting over the past 2 days. They report the vomiting occurring after feeds and becoming increasingly forceful. The vomit is non-bilious and non-bloody in nature. His vitals are stable other than a mild tachycardia and on examination, the child appears irritable with a sunken fontanelle. On inspection, there is visible peristalsis and palpation reveals an olive-sized mass in the epigastrium. Which of the following is the most likely diagnosis?

Pyloric stenosis

An eight-week-old boy is brought to the GP by his parents who are concerned at the appearance of his scrotum. The child was born via an uncomplicated vaginal delivery at 37 weeks gestation. Although he was small for gestational age, he has met all growth milestones since birth. Abdominal examination is normal. Examination of the genitals reveals an empty looking right scrotum. A small, mobile and well-defined mass is palpable in the right inguinal canal. The left testicle can be palpated in the left scrotum. The penis appears normal. Which of the following is the most appropriate next step in management?

Re-review at 3 months old

A 4-year-old boy is brought to the physician by his parents for bedwetting. He went 3 months without wetting the bed but then started again 6 weeks ago. He has been wetting the bed about 1-2 times per week. He has not had daytime urinary incontinence or dysuria. His teachers report that he is attentive in preschool and plays well with his peers. He is able to name 5 colors, follow three-step commands, and recite his address. He can do a somersault, use scissors, and copy a square. Physical examination shows no abnormalities. Which of the following is the most appropriate next step in management?

Reassurance

An anxious mother brings her 4-month-old son for evaluation of stridor which has been present from around day 15 of life. Since then it has been getting louder. The child is feeding and growing well. There is no breathlessness, respiratory distress, or associated recession in the child. At present, there is intermittent stridor which increases when the child cries, but the child is otherwise well. Which of the following is the most appropriate management plan?

Reassure the parents that it is a self-resolving condition and monitor

An 8-year-old boy has had a 3-day history of left-sided otalgia and purulent aural discharge. In the past 24 hours, he has developed a fever of 38 degrees Celsius and has been complaining of tenderness behind his ear. On examination, his left ear looks more prominent than the right and is pushed downwards and outwards. On palpation there is tenderness behind the ear and otoscopy reveals a left-sided bulging tympanic membrane. Which of the following is the most appropriate next management step?

Refer urgently to ENT

A 7-month-old girl is brought to the ED with fever, shortness of breath and difficulty feeding. Her parents report that she's had a runny nose for the last two days. On examination, she is working hard to breathe and has scattered crackles and wheeze on auscultation of the chest. Her vital signs are as follows: Temperature: 37.8 Celsius (100 F) Oxygen saturations: 93% on room air Respiratory rate: 30 breaths per minute What is the most likely pathogen causing this presentation?

Respiratory syncytial virus (RSV)

A concerned parent brings in her 2-year-old son complaining of excessive watering of the eyes. On examination, the right eye appears larger than the left (buphthalmos) and there is a white opacity of the right pupil with no light stimuli. What is the most likely diagnosis?

Retinoblastoma

A 1-year-old child is brought to the GP by her mother who is concerned about a rash on her body. The mother states the child was sent home from nursery 4 days ago with a high fever, which was treated at home with paracetamol and has now settled. However, the mother is now concerned about a rash that has appeared all over the child's body, which you note to be non-tender and maculopapular. She is up to date on all her vaccinations. What is the most likely diagnosis?

Roseola infantum

An 8-month-old girl is brought to the emergency department because of fever, vomiting, and diarrhea for 3 days. Her parents report at least 10 watery stools daily. She has had three upper respiratory tract infections since she started daycare 2 months ago, but has otherwise been developing normally. Her mother has a history of celiac disease. The patient is at the 57th percentile for height and the 65th percentile for weight. Her immunizations are incomplete. Her temperature is 38.5°C (101.3°F), pulse is 145/min, and blood pressure is 92/54 mm Hg. Examination shows dry mucous membranes and decreased skin turgor. Bowel sounds are hyperactive. A complete blood count and serum concentrations of glucose, urea nitrogen, and creatinine are within the reference range; there is hypokalemia. Intravenous fluid resuscitation is begun. What is the most likely diagnosis?

Rotavirus

A 4-year-old girl presents to the Emergency Department with her father after being sent in urgently by her GP. She is having obvious difficulty breathing and is leaning forwards with her arms propped on the side of her chair. In addition to her positioning on the chair, you can see nasal flaring and tracheal tug. She is drooling and you can hear a harsh high-pitched noise on inspiration. Her father says that she has progressively deteriorated over a couple of days and that she now has difficulty swallowing, and when she speaks she is hoarse. As part of your observations, you find that she has a temperature of 39.1 °C. Considering the likely diagnosis, which of the following treatments should be administered immediately?

Securing of the airways and supplemental oxygen

A 3-year-old boy is brought to the physician by his parents because of a 6-month history of worsening mobility issues. During this period, his parents noticed that he had occasional falls and increasing difficulties climbing stairs and running. The boy had a normal development up until then; he was able to walk by the age of 15 months. There is no personal or family history of serious illness. He is at the 10th percentile for height and 25th percentile for weight. Vital signs are within normal limits. Musculoskeletal examination shows enlarged calf muscles bilaterally. Deep tendon reflexes are 1+ on the lower extremities and 2+ on the upper extremities. He has a waddling gait and when asked to get up from the floor, he supports himself with his hands on his legs to get to an upright position. Which of the following is the most appropriate initial step in diagnosis?

Serum creatine kinase concentration

Hyperbilirubinemia associated with Crigler-Najjar syndrome type I is caused by which of the following?

Severe deficiency of uridine diphosphate glucuronosyltransferase

A 13-year-old Hispanic boy is brought to the physician by his mother because of left groin pain for 1 month. The pain radiates to his left knee and is aggravated on walking. He fell during soccer practice 5 weeks ago but did not see a doctor about it and does not recall any immediate and persistent pain after the event. He has hypothyroidism. His only medication is levothyroxine. His immunizations are up-to-date. He appears uncomfortable. He is at the 50th percentile for height and at the 95th percentile for weight. His temperature is 37.1°C (98.9°F), pulse is 77/min, respirations are 14/min, and blood pressure is 100/70 mm Hg. The patient has a left-sided, antalgic gait. The left lower extremity is externally rotated. The left hip is tender to palpation and internal rotation is limited by pain. Laboratory studies show:

Slipped capital femoral epiphysis

A 16-year-old boy comes to the physician for a routine health maintenance examination. He feels well. He has no history of serious illness. He is at the 60th percentile for height and weight. Vital signs are within normal limits. The lungs are clear to auscultation. A grade 3/6 systolic ejection crescendo-decrescendo murmur is heard along the lower left sternal border. The murmur decreases in intensity on rapid squatting and increases in intensity when he performs the Valsalva maneuver. This patient is at increased risk for which of the following complications?

Sudden cardiac death

A 15-year-old boy presents to the primary care physician complaining of constant pain around the knee. The pain has been worsening over several months and he has also lost some weight over the same time period. On examination, a swelling is noted at the site of pain. The lab investigations show a normal FBC, normal ESR but an elevated alkaline phosphatase. X-Ray of the knee is ordered and the diagnosis of osteosarcoma is made. Which of the following X-ray findings is most characteristic of osteosarcoma?

Sunburst pattern

An 18-month-old boy is brought to the physician by his parents for the evaluation of passing large amounts of dark red blood from his rectum for 2 days. His parents noticed that he has also had several episodes of dark stools over the past 3 weeks. The parents report that their child has been sleeping more and has been more pale than usual over the past 24 hours. The boy's appetite has been normal and he has not vomited. He is at the 50th percentile for height and 50th percentile for weight. His temperature is 37°C (98.6°F), pulse is 135/min, respirations are 38/min, and blood pressure is 90/50 mm Hg. Examination shows pale conjunctivae. The abdomen is soft and nontender. There is a small amount of dark red blood in the diaper. Laboratory studies show: Which of the following is most likely to confirm the diagnosis?

Technetium-99m pertechnetate scan

A 2-week old newborn is brought to the physician for a follow-up examination after the initial newborn examination showed asymmetry of the legs. She was born at term to a 26-year-old woman, gravida 3, para 2. Pregnancy was complicated by a breech presentation and treated with an emergency lower segment transverse cesarean section. The newborn's head circumference is 35 cm (13.7 in). She is at the 60th percentile for length and 75th percentile for weight. Cardiac examination shows no abnormalities. The spine is normal. Abduction of the right hip after cupping the pelvis and flexing the right hip and knee causes a palpable clunk. The feet have no deformities. Ultrasonography of the hip determines the angle between lines along the bone acetabulum and the ilium is 50°. Which of the following is the most appropriate next step in management?

Treat using a harness

Which vitamin deficiency is associated with an increased risk of severe measles infection?

Vitamin A

A 10-year-old boy presents with loose, foul-smelling greasy stools and short stature. He has a history of recurrent chest infections. A sweat test is positive. Which of the following complications is most likely to be seen as a result of the nutritional deficiencies associated with his underlying condition?

Weak bones, night blindness, hemorrhagic disease

An 11-month-old boy is brought to the emergency department because of intermittent episodes of inconsolable crying for 4 hours. The parents report that the patient does not appear to be in discomfort between episodes, and moves and plays normally. The episodes have occurred at roughly 15-minute intervals and have each lasted a few minutes before subsiding. He has also vomited 3 times since these episodes began. The first vomitus appeared to contain food while the second and third appeared pale green in color. The patient was born at term and has been healthy. His immunizations are up-to-date. He has no history of recent travel. His older brother has Crohn's disease. The patient is at 50th percentile for height and 60th percentile for weight. He does not appear to be in acute distress. His temperature is 37.1°C (98.8°F), pulse is 125/min, respirations are 36/min, and blood pressure is 85/40 mm Hg. During the examination, the patient begins to cry and draws his knees up to his chest. Shortly thereafter, he passes stool with a mixture of blood and mucous; the patient's discomfort appears to resolve. Abdominal examination shows a sausage-shaped abdominal mass in the right upper quadrant. Which of the following is the most appropriate next step in the management of this patient?

air enema

A 6-year-old child presents to your clinic unwell with a fever and sore throat. Upon further history taking you discover he has not had any vaccinations. On examination, there is a grey-white colored membrane covering his tonsils. What is the most likely diagnosis?

diphtheria

A 9-year-old girl is brought to the physician by her mother because of a 3-day history of face and foot swelling, dark urine, and a rash on her hands and feet. The mother reports that her daughter has had a low-grade fever, shortness of breath, and a dry cough for the past 8 days. She has had generalized weakness and pain in her right knee and ankle. She has a ventricular septum defect that was diagnosed at birth. The patient appears lethargic. Her temperature is 38.4 (101.1°F), pulse is 130/min, respirations are 34/min, and blood pressure is 110/60 mm Hg. Examination shows small, non-blanching, purple lesions on her palms, soles, and under her fingernails. There is edema of the eyelids and feet. Funduscopic examination shows retinal hemorrhages. Holosystolic and early diastolic murmurs are heard. Laboratory studies show: Transthoracic echocardiography shows a small outlet ventricular septum defect and a mild right ventricular enlargement. There are no wall motion abnormalities, valvular heart disease, or deficits in the pump function of the heart. Blood cultures grow Streptococcus pyogenes. Which of the following is the most likely diagnosis?

infective endocarditis

A 6-month-old boy presents with his mother who reports a two-day history of worsening episodes of inconsolable crying. During these episodes, his mother says he draws up his legs. He has vomited four times, and this morning a red, jelly-like stool was found in his diaper. What is the most likely diagnosis?

intussusception

An 8-year-old boy is brought to the office because of bilateral ankle swelling that occurred overnight. He has stopped wearing socks because they feel too tight. He has type 1 diabetes mellitus treated with insulin. He has received all scheduled immunizations. His temperature is 37.0°C (98.6°F), pulse is 90/min, respirations are 16/min, and blood pressure is 112/75 mm Hg. Cardiopulmonary and abdominal examinations show no abnormalities. There is moderate scrotal edema, and 2+ pitting edema of the lower extremities. Laboratory studies show: Treatment with prednisone is begun. Over the following weeks, there is a significant improvement in the patient's peripheral edema and urinalysis findings. Which of the following is the most likely diagnosis?

minimal change disease

A 13-year-old girl is brought to the physician by her father because of a 1-month history of pain in her right knee. She is a competitive volleyball player and has missed several games recently due to pain. Examination shows swelling distal to the right knee joint on the anterior surface of the proximal tibia; there is no overlying warmth or deformity. Extension of the right knee against resistance is painful. Which of the following structures is attached to the affected anterior tibial area?

patellar ligament

A 12-month-old girl is brought to the physician because she is unable to sit and has not learned how to crawl. She keeps her hips and elbows flexed and her parents have to use considerable force to passively extend her joints. She attained neck control at 4 months and could roll from front to back at 5 months of age. She does not engage in play, reach for toys, or maintain eye contact. She babbles and does not mimic sounds. She does not follow simple instructions. She has difficulty swallowing solid foods and often coughs at meal times. Her maternal cousin has Down syndrome. Her vital signs are within normal limits. She is at the 25th percentile for length and 10th percentile for weight. Neurological examination shows increased muscle tone in all extremities. The ankle clonus and extensor plantar responses are present bilaterally. The Moro reflex is present. An MRI of the head shows periventricular leukomalacia. Which of the following is the most important risk factor for the development of this condition? A Neonatal jaundice B Advanced paternal age C Maternal smoking during pregnancy D Premature birth E Congenital rubella infection F Maternal alcohol use during pregnancy G Congenital toxoplasmosis H Congenital CMV infection I Advanced maternal age

premature birth

A 2-year-old girl is brought to the physician because of high-grade fever and crying while passing urine. Four months ago, she was treated for a febrile urinary tract infection with cefixime. There is no family history of serious illness. Her temperature is 39.2°C (102.6°F) and pulse is 123/min. Physical examination shows no abnormalities. Urine dipstick shows leukocyte esterase; urinalysis shows WBCs. Urine culture shows Escherichia coli sensitive to cefixime. A voiding cystourethrogram is shown. Without treatment, which of the following is this patient most likely to develop?

renal scarring

A term 8lb male infant is born vaginally to a 27-year old gravida 2 mother following an uncomplicated pregnancy. Shortly after birth, he begins to cough, followed by a choking episode, difficulty handling secretions, and cyanosis. During the resuscitation, placement of an orogastric tube meets resistance at 10 cm. He is transferred to the level II nursery for evaluation and management of respiratory distress. What is the most likely diagnosis

transesophageal fistula