1.
Two weeks after a viral syndrome, a 9-year-old girl presents to your clinic with a complaint of several days of drooping of her mouth. In addition to the drooping of the left side of her mouth, you note that she is unable to completely shut her left eye. Her smile is asymmetric, but her examination is otherwise normal. This girl likely has:
Correct Answer
E. Bell palsy
Explanation
The girl's symptoms of drooping of the mouth and inability to completely shut her left eye, along with an asymmetric smile, are indicative of Bell palsy. Bell palsy is a condition that causes sudden weakness or paralysis of the muscles on one side of the face, typically due to inflammation of the facial nerve. It is often preceded by a viral infection, such as a viral syndrome, which is consistent with the girl's history. Guillain-Barré syndrome, botulism, cerebral vascular accident, and brainstem tumor would present with different symptoms and are less likely in this case.
2.
An infant can move his head from side to side while following a moving object, can lift his head from a prone position 45° off the examining table, smiles when encouraged, and makes cooing sounds. He cannot maintain a seated position. The most likely age of the infant is:
Correct Answer
B. 3 months
Explanation
Based on the given information, the infant is able to move his head from side to side while following a moving object, lift his head from a prone position 45° off the examining table, smile when encouraged, and make cooing sounds. These motor and social skills typically develop around the age of 3 months. The fact that the infant cannot maintain a seated position suggests that he is not yet at the age of 6 months or older, where sitting with support becomes more common. Therefore, the most likely age of the infant is 3 months.
3.
A child is brought to your clinic for a routine examine. She can dress with help, can ride a tricycle, knows her own age, and can speak in short sentences. She had difficulty in copying a square. The age of this child is most likely:
Correct Answer
C. 3 years
Explanation
Based on the given information, the child can dress with help, ride a tricycle, knows her own age, and can speak in short sentences. These are developmental milestones typically achieved by a 3-year-old child. The difficulty in copying a square is also common at this age as it requires more advanced fine motor skills. Therefore, the most likely age of this child is 3 years.
4.
A 4-year-old girl is noticed by her grandmother to have a limp and a somewhat swollen left knee. The parents report that the patient occasionally complains of pain in that knee. An ophthalmologic examination reveals findings as depicted in the photograph. The condition most likely to be associated with these findings is:
Correct Answer
A. Juvenile rheumatoid arthritis
Explanation
The ophthalmologic findings in the photograph show uveitis, which is inflammation of the uvea (middle layer of the eye). Uveitis is a common ocular manifestation of juvenile rheumatoid arthritis (JRA). JRA is an autoimmune disorder that causes chronic inflammation in the joints, and it can also affect other organs, including the eyes. The patient's limp and swollen knee, along with occasional pain, are consistent with joint involvement seen in JRA. Therefore, the correct answer is Juvenile rheumatoid arthritis.
5.
The previously healthy 4-year-old child pictured presents to the emergency room with a 2-day history of a brightly erythematous rash and temperature of 40°C (104°F). The exquisitely tender, generalized rash is worse in the flexural and perioral areas. The child is admitted and over the next day develops crusting and fissuring around the eyes, mouth, and nose. The desquamation of skin shown occurs with gentle traction. This child most likely has:
Correct Answer
B. StapHylococcal scalded skin syndrome
Explanation
The child's presentation is consistent with Staphylococcal scalded skin syndrome (SSSS). SSSS is a bacterial infection caused by Staphylococcus aureus that produces an exfoliative toxin. The toxin causes separation of the epidermis from the dermis, resulting in a generalized rash that is worse in flexural and perioral areas. The crusting and fissuring around the eyes, mouth, and nose, along with the desquamation of skin with gentle traction, are characteristic features of SSSS. Epidermolysis bullosa, erythema multiforme, drug eruption, and scarlet fever do not typically present with these specific findings.
6.
You are counseling an adolescent patient about the long-term management of her asthma while she is away at college. She brought an article she found on the Internet that promotes an herbal supplement purported to be a “safe, natural” treatment for asthma. You recall a recent study in the medical literature showing inhaled steroids to be statistically superior to the advertised herbal supplement at preventing asthma exacerbations at the p <0.05 level. You explain to her that this means that:
Correct Answer
D. The odds are less than 1 in 20 that the differences observed were only a chance variation
Explanation
The correct answer is "The odds are less than 1 in 20 that the differences observed were only a chance variation." This means that the study results are statistically significant, indicating that the inhaled steroids are more effective than the herbal treatment at preventing asthma exacerbations. The p-value of less than 0.05 suggests that the observed differences are unlikely to be due to chance alone. Therefore, it would not be advisable to rely on the herbal treatment as it has not been proven to be as effective as the inhaled steroids.
7.
A previously healthy 8-year-old boy has a 3-week history of low-grade fever of unknown source, fatigue, weight loss, myalgia, and headaches. On repeated examinations during this time, he is found to have developed a heart murmur, petechiae, and mild splenomegaly. The most likely diagnosis is:
Correct Answer
D. Endocarditis
Explanation
The most likely diagnosis in this case is endocarditis. The symptoms of low-grade fever, fatigue, weight loss, myalgia, and headaches, along with the development of a heart murmur, petechiae, and mild splenomegaly, are suggestive of endocarditis. Endocarditis is an infection of the inner lining of the heart chambers and valves, often caused by bacteria. It can lead to various systemic symptoms and complications, including heart murmurs and splenomegaly. The other options, such as rheumatic fever, Kawasaki disease, scarlet fever, and tuberculosis, do not typically present with the combination of symptoms described in the case.
8.
After you make the diagnosis in the previous case, you explain the findings to the family and instruct the family to:
Correct Answer
C. Ensure that the patient receives antibiotic propHylaxis for dental procedures
Explanation
The correct answer is to ensure that the patient receives antibiotic prophylaxis for dental procedures. This is because the previous case likely involved a diagnosis of infective endocarditis, which is an infection of the heart valves. Antibiotic prophylaxis is recommended for patients with certain heart conditions, such as those with prosthetic heart valves, to prevent bacterial infections during dental procedures. This is important because bacteria from the mouth can enter the bloodstream during dental procedures and potentially infect the heart valves. Therefore, ensuring that the patient receives antibiotic prophylaxis is crucial in preventing complications.
9.
A 5-year-old boy who was previously healthy has a 1-day history of low-grade fever, colicky abdominal pain, and a skin rash. He is alert but irritable; temperature is 38.6°C (101.5°F). A diffuse, erythematous, maculopapular, and petechial rash is present on his buttocks and lower extremities, as shown in the following figure. There is no localized abdominal tenderness or rebound; bowel sounds are active. Laboratory data demonstrate:
Urinalysis: 30 red blood cells per high-powered field, 2+ protein
Stool: guaiac positive
Platelet count: 135,000/μL
These findings are most consistent with:
Correct Answer
A. AnapHylactoid purpura
Explanation
The given clinical presentation of a 5-year-old boy with low-grade fever, colicky abdominal pain, and a skin rash, along with laboratory findings of red blood cells in the urine, positive stool guaiac, and a slightly decreased platelet count, is most consistent with anaphylactoid purpura. Anaphylactoid purpura, also known as Henoch-Schönlein purpura, is a systemic vasculitis that commonly affects children. It typically presents with a purpuric rash, abdominal pain, and joint pain. The presence of blood in the urine and positive stool guaiac are characteristic of the disease. Meningococcemia, child abuse, leukemia, and hemophilia B are not consistent with the given clinical presentation and laboratory findings.
10.
A 4-month-old baby boy has just arrived in the emergency room. He is cold and stiff. History from the parents is that the seemingly healthy infant had been placed in his crib for the night, and when they next saw him, in the morning, he was dead. Physical examination is uninformative. Routine whole-body x-rays are shown. The most likely diagnosis is:
Correct Answer
E. Battery
11.
A mother brings an 18-month-old to the emergency center with the concern that the child may have ingested a substance. Which of the following is a contraindication to the use of ipecac in this child:
Correct Answer
C. Ingestion of alkali
Explanation
Ingestion of alkali is a contraindication to the use of ipecac in an 18-month-old child because alkali substances can cause severe damage to the esophagus and stomach. Ipecac induces vomiting, which can further irritate and potentially worsen the damage caused by alkali ingestion. Therefore, it is not recommended to use ipecac in this situation.
12.
A mother calls you on the telephone and says that her 4-year-old son bit the hand of her 2-year-old son 2 days previously. The area around the laceration has become red, indurated, and swollen, and he has a temperature of 39.4°C (103°F). Your response should be to:
Correct Answer
B. Admit the child to the hospital immediately for surgical debridement and antibiotic treatment
Explanation
The child's symptoms, including redness, swelling, induration, and high fever, suggest that the bite wound has become infected. In cases of infected wounds, surgical debridement and antibiotic treatment are necessary to prevent further complications and promote healing. Admitting the child to the hospital immediately allows for prompt medical intervention and close monitoring of the infection.
13.
The adolescent shown presents with a 14-day history of multiple oval lesions over her back. The rash began with a single lesion over the lower abdomen (A); the other lesions developed over the next days (B). These lesions are slightly pruritic. The likely diagnosis is:
Correct Answer
B. Pityriasis rosea
Explanation
The correct answer is Pityriasis rosea. Pityriasis rosea is a common skin condition characterized by oval-shaped lesions that may start with a single lesion and then develop more over time. The lesions are usually slightly itchy and typically appear on the trunk, including the back. Contact dermatitis, seborrheic dermatitis, lichen planus, and psoriasis are all different skin conditions with different clinical presentations and characteristics.
14.
The most appropriate initial therapy for the patient in the previous question is:
Correct Answer
E. Observation and topical emollients
Explanation
Observation and topical emollients are the most appropriate initial therapy for the patient in the previous question. This approach involves closely monitoring the patient's condition and using topical emollients to provide relief and moisturize the affected area. It is a conservative treatment option that is often recommended for mild cases of skin conditions, allowing for natural healing to occur. This approach avoids the potential side effects and risks associated with more aggressive treatments such as phototherapy, high-dose topical steroid therapy, systemic antifungal agents, or coal-tar shampoos.
15.
A very concerned mother brings a 2-year-old child to your office because of multiple episodes of a brief, shrill cry followed by a prolonged expiration and apnea. You have been following this child in your practice since birth and know that the child is a product of a normal pregnancy and delivery, has been growing and developing normally, and has no acute medical problems. The mother relates that the first episode in question occurred immediately after the mother refused to give the child some juice. The child became cyanotic and unconscious and had generalized clonic jerks. A few moments later the child awakened and had no residual effects. A second episode of identical nature occurred at the grocery store when the father of the child refused to purchase a toy for the child. Your physical examination reveals a totally delightful and normal child. The most likely diagnosis in this case is:
Correct Answer
E. Breath-holding spell
Explanation
Breath-holding spell is the most likely diagnosis in this case. Breath-holding spells are episodes in which a child involuntarily holds their breath, leading to cyanosis (bluish discoloration of the skin) and loss of consciousness. These episodes are often triggered by emotional stress or frustration, such as the child being denied something they want. The child in this case has been growing and developing normally, has no acute medical problems, and appears normal on physical examination, which is consistent with breath-holding spells. Seizure disorder, drug ingestion, hyperactivity with attention deficit, and pervasive development disorder do not explain the specific symptoms described in the case.
16.
The most appropriate course of action in the previous case would be to:
Correct Answer
E. Reassure the family of the likely benign nature of the problem and offer counseling for appropriate behavior modification
Explanation
The most appropriate course of action in this case would be to reassure the family of the likely benign nature of the problem and offer counseling for appropriate behavior modification. This is because the question mentions a "likely benign nature of the problem," suggesting that the child's condition is not serious. Therefore, it would be appropriate to provide reassurance to the family and offer counseling to help modify the child's behavior.
17.
The 3-day-old infant pictured has a facial rash. The most likely diagnosis is:
Correct Answer
B. Neonatal acne
Explanation
Neonatal acne is the most likely diagnosis for the 3-day-old infant's facial rash. Neonatal acne is a common condition that occurs in newborns and is characterized by small, red bumps or pimples on the face. It is caused by hormonal changes and usually resolves on its own within a few weeks or months. Herpes, milia, seborrheic dermatitis, and eczema are less likely diagnoses for a newborn with a facial rash.
18.
You are called to the emergency room to see one of your patients. The father of this 3-year-old was spraying the yard with an unknown insecticide. In the emergency room, the child is noted to have bradycardia, muscle fasciculations, meiosis, wheezing, and profound drooling. The most likely agent included in this pesticide is:
Correct Answer
A. OrganopHospHate
Explanation
The symptoms described in the question, such as bradycardia, muscle fasciculations, meiosis, wheezing, and profound drooling, are consistent with organophosphate poisoning. Organophosphates are a class of insecticides that inhibit the activity of the enzyme acetylcholinesterase, leading to an accumulation of acetylcholine in the body. This results in overstimulation of the cholinergic system, leading to the symptoms described. Chlorophenothane (DDT), sodium cyanide, warfarin, and paraquat do not typically cause these specific symptoms.
19.
A 2-year-old child (A) presents with a four-day history of a rash limited to the feet and ankles. The papular rash is both pruritic and erythematous. The 3-month-old sibling of this patient (B) has similar lesions also involving the head and neck. Appropriate treatment for this condition includes:
Correct Answer
B. Permethrin
Explanation
Permethrin is the appropriate treatment for this condition because the presentation of a papular rash that is both pruritic and erythematous, limited to the feet and ankles in a 2-year-old child, along with similar lesions involving the head and neck in a 3-month-old sibling, suggests scabies. Permethrin is a topical scabicide that is effective in treating scabies infestations. It works by killing the mites that cause scabies and their eggs. Therefore, Permethrin is the correct choice for treating this condition.
20.
An 8-hour-old infant develops increased respiratory distress, hypothermia, and hypotension. A CBC demonstrates a WBC of 2500/μL with 80% bands. Which of the following diagnoses is most likely?
Correct Answer
C. Group B streptococcal pneumonia
Explanation
The correct answer is Group B streptococcal pneumonia because it is a common cause of early-onset neonatal sepsis, which can present with respiratory distress, hypothermia, and hypotension. The low white blood cell count with a high percentage of bands suggests an infection. Gonococcal eye infection and chlamydial pneumonia are less likely in this case because they typically present with conjunctivitis rather than systemic symptoms. Diaphragmatic hernia and transient tachypnea of the newborn would not explain the hypotension and low white blood cell count.
21.
A 16-year-old basketball player complains of pain in his knees. A physical examination reveals, in addition to tenderness, a swollen and prominent tibial tuberosity. Radiographs of the area are unremarkable. The most likely diagnosis is:
Correct Answer
A. Osgood-Schlatter disease
Explanation
Osgood-Schlatter disease is the most likely diagnosis for a 16-year-old basketball player complaining of knee pain with tenderness and a swollen and prominent tibial tuberosity. This condition is commonly seen in active adolescents and is characterized by inflammation at the insertion of the patellar tendon on the tibial tuberosity. Radiographs are usually normal in Osgood-Schlatter disease, which supports the unremarkable findings mentioned in the question. Popliteal cyst, slipped capital femoral epiphysis, Legg-Calvé-Perthes disease, and gonococcal arthritis are less likely diagnoses in this case.
22.
You are performing a well-child examination on a new patient, the 1-year-old child shown in the picture. Your next action should be to:
Correct Answer
E. Refer immediately to opHthalmology, as central vision may fail to develop if the diagnosis and treatment are delayed
Explanation
The picture shows a child with a noticeable deviation of the eye. This is likely a case of strabismus, which is a misalignment of the eyes. If left untreated, strabismus can lead to a condition called amblyopia, or lazy eye, where the brain favors one eye over the other and central vision fails to develop properly. Therefore, it is important to refer the child to ophthalmology immediately for diagnosis and treatment to prevent long-term vision problems.
23.
You are seeing a 2-month-old infant, brought by her father for a well-child examination. He has concerns about maintaining a safe environment for his child. In providing age-appropriate anticipatory guidance, you tell him that:
Correct Answer
B. His 2-month-old should not be given solid food at this time
Explanation
At 2 months old, infants should only be receiving breast milk or formula. Solid foods should not be introduced until around 4-6 months of age, as their digestive systems are not yet developed enough to handle solid foods. Introducing solid foods too early can increase the risk of digestive issues, allergies, and choking.
24.
An infant who sits with only minimal support, attempts to attain a toy beyond reach, and rolls over from the supine to the prone position, but does not have a pincer grasp, is at a developmental level of:
Correct Answer
C. 6 months
Explanation
An infant who is able to sit with only minimal support, attempt to reach for a toy beyond their reach, and roll over from the supine to the prone position, but does not have a pincer grasp, is at a developmental level of 6 months. At this age, infants are typically able to sit with support, start reaching for objects, and roll over. The absence of a pincer grasp suggests that the infant has not yet developed the fine motor skills required for this milestone, which usually occurs around 9 months of age.
25.
A 5-year-old boy presents with the severe rash pictured as follows. The rash is pruritic, and it is especially intense in the flexural areas. The mother reports that the symptoms began in infancy (when it also involved the face) and that her 6-month-old child has similar symptoms. The most likely diagnosis of this condition is:
Correct Answer
D. Eczema
Explanation
The most likely diagnosis for the severe rash in a 5-year-old boy, which is pruritic and especially intense in the flexural areas, is eczema. The fact that the symptoms began in infancy, involved the face, and that the child's 6-month-old sibling has similar symptoms suggests a chronic condition like eczema. Seborrheic dermatitis, superficial candidiasis, psoriasis, and contact dermatitis may also cause rashes, but the presentation and history described in the question are more consistent with eczema.
26.
Appropriate treatment for the condition described in the previous question includes:
Correct Answer
D. Moisturizers and topical steroids
Explanation
Moisturizers and topical steroids are appropriate treatments for the condition described in the previous question because they can help alleviate symptoms such as dryness, itching, and inflammation. Moisturizers help to hydrate the skin and reduce dryness, while topical steroids have anti-inflammatory properties and can help reduce itching and inflammation. These treatments can provide relief and improve the overall condition of the skin.
27.
An 18-month-old infant has an intensely pruritic scalp, especially in the occipital region, with 0.5-mm lesions noted at the base of hair shafts, as shown in the picture. The mother of this infant has been using the same hairbrush for herself and for her other two children (ages 2 months and 36 months). Which of the following therapies should be avoided?
Correct Answer
A. Treatment of all household contacts with 1% lindane (Kwell)
Explanation
Treatment of all household contacts with 1% lindane (Kwell) should be avoided because lindane is a neurotoxic agent that can be absorbed through the skin and cause adverse effects, especially in young children. It is not recommended for use in infants and children under 2 years old due to the risk of neurotoxicity. Safer alternatives such as permethrin or pyrethrin-based products should be used instead.
28.
You are called by a general practitioner to consult on a patient admitted to the hospital 4 days ago. The patient is a 7-month-old white boy with poor weight gain for the past 3 months, who has not gained weight in the hospital despite seemingly adequate nutrition. His guardian is his maternal aunt, as his mother is in jail for unknown reasons. You take a detailed diet history from the guardian, and the amounts of formula and baby food intake seem appropriate for age. Physical examination reveals an active, alert infant with a strong suck reflex who appears wasted. You note generalized lymphadenopathy with hepatomegaly. In addition, you find a severe case of oral candidiasis that apparently has been resistant to treatment. Which of the following is the most appropriate next step in the evaluation or treatment of this child?
Correct Answer
B. Order HIV PCR testing because this is likely the presentation of congenitally acquired HIV
Explanation
The patient's poor weight gain, lack of weight gain despite adequate nutrition, and presence of oral candidiasis that is resistant to treatment are all suggestive of an underlying immunodeficiency. The presence of generalized lymphadenopathy and hepatomegaly further support this suspicion. Congenitally acquired HIV can present with these symptoms, and HIV PCR testing is the most appropriate next step to confirm the diagnosis.
29.
A 2-year-old boy has been vomiting intermittently for 3 weeks and has been irritable, listless, and anorectic. His use of language has regressed to speaking single words. In your evaluation of this patient, the least likely diagnosis to consider is:
Correct Answer
D. Food allergy
Explanation
Given the patient's symptoms of vomiting, irritability, listlessness, anorexia, and regression in language skills, the least likely diagnosis to consider is food allergy. Food allergies typically present with symptoms such as hives, itching, swelling, wheezing, or anaphylaxis, but not with the symptoms described in the patient. The other options, subdural hematoma, brain tumor, tuberculous meningitis, and lead poisoning, are all more likely causes for the patient's symptoms.
30.
Among the following, the least likely risk factor for hearing impairment is:
Correct Answer
A. A maternal history of use of pHenytoin during pregnancy
Explanation
A maternal history of use of phenytoin during pregnancy is the least likely risk factor for hearing impairment because phenytoin is not known to directly cause hearing impairment. Phenytoin is an anticonvulsant medication used to treat seizures, and while it may have other potential side effects, hearing impairment is not typically associated with its use. On the other hand, family history of hearing impairment, craniofacial abnormalities, low birth weight, and neonatal hyperbilirubinemia have all been identified as risk factors for hearing impairment in various studies.
31.
An 8-month-old infant has a 2-day history of diarrhea and poor fluid intake. You diagnose a 10 to 15% dehydration. Which of the following fluids is appropriate to begin immediate resuscitation?
Correct Answer
C. Normal saline
Explanation
Normal saline is the appropriate fluid to begin immediate resuscitation in an 8-month-old infant with 10 to 15% dehydration. Normal saline is an isotonic solution that helps restore fluid and electrolyte balance in the body. It contains a balanced concentration of sodium and chloride, which are important for maintaining proper hydration. D5 1/4 normal saline and D5 1/2 normal saline are not appropriate because they contain dextrose, which can increase osmolarity and worsen diarrhea. Whole blood and D10W are not indicated for resuscitation in this scenario.
32.
In this patient, you decide to give 20 mL/kg of the chosen fluid. A reasonable period of time over which to infuse this fluid is:
Correct Answer
B. 60 min
Explanation
A reasonable period of time to infuse 20 mL/kg of fluid would be 60 minutes. This is because infusing the fluid over a shorter period of time, such as 2.5 minutes, could lead to fluid overload and potential complications. On the other hand, infusing the fluid over a longer period of time, such as 4 hours, 8 hours, or 24 hours, may not provide the necessary hydration or therapeutic effect in a timely manner. Therefore, infusing the fluid over 60 minutes strikes a balance between delivering the fluid efficiently and minimizing the risk of complications.
33.
You are seeing an established patient, a four-year-old girl brought in by her mother for vaginal itching and irritation. She is toilet trained and has not complained of frequency or urgency, nor has she noted any blood in her urine. Her mother noted she has been afebrile and has not complained of abdominal pain. Mom denies the risk of inappropriate contact; the girl also denies anyone “touching her there.” Your physical examination of the perineum is significant for the lack of foul odor or discharge. You do note some erythema of the vulvar area, but the hymenal ring is intact, without evidence of trauma. The appropriate course of action should be to:
Correct Answer
B. Reassure the mother, and counsel her to stop giving the girl bubble baths, have the girl wear only cotton underwear, and improve hygiene
Explanation
Based on the information provided, the girl's symptoms of vaginal itching and irritation are most likely due to non-infectious causes. The lack of foul odor or discharge, intact hymenal ring, and absence of trauma suggest that there is no foreign body or infection present. Therefore, the appropriate course of action is to reassure the mother and provide guidance on improving hygiene, such as avoiding bubble baths and using cotton underwear. This approach addresses the most likely cause of the symptoms and is a conservative first step before considering more invasive interventions or referrals.
34.
A 20-month-old child is brought to the emergency department because of fever and irritability and refusal to move his right lower extremity. Physical examination reveals a swollen and tender right knee that resists passive motion. The most important test to confirm the impression of septic arthritis is:
Correct Answer
A. Examination of joint fluid
Explanation
Examination of joint fluid is the most important test to confirm the impression of septic arthritis. Septic arthritis is an infection of the joint space, and examination of joint fluid allows for the direct identification of the causative organism. It also helps in determining the appropriate antibiotic therapy. X-ray of the knee may show signs of joint inflammation but cannot definitively confirm septic arthritis. ESR and CBC are nonspecific tests that may support the diagnosis but cannot confirm it. Blood culture is important but may not always be positive in cases of septic arthritis.
35.
A 16-year-old high school boy sustained an abrasion of the knee after a fall while Rollerblading in the school yard. School records reveal that his last DPT booster was at age 6. In this situation, which of the following is appropriate?
Correct Answer
B. Adult tetanus and dipHtheria toxoid (Td)
Explanation
The appropriate choice in this situation is to administer an adult tetanus and diphtheria toxoid (Td) vaccine. Tetanus is caused by a bacterial infection that can enter the body through open wounds, such as the abrasion on the knee. The last DPT booster was received at age 6, which means the individual is due for a booster vaccine. The Td vaccine provides protection against both tetanus and diphtheria, making it the appropriate choice in this case.
36.
A five-year-old boy is brought into the emergency room immediately after an unfortunate altercation with a neighbor’s immunized Chihuahua that occurred while the child was attempting to dress the dog as a superhero. The fully immunized child has a small, irregular, superficial laceration on his right forearm that has stopped bleeding. His neuromuscular examination is completely normal, and his perfusion is intact. Management should include:
Correct Answer
C. Copious irrigation
Explanation
In this scenario, the child has a small, superficial laceration on his forearm after an encounter with a neighbor's immunized Chihuahua. The wound has already stopped bleeding, and the child's neuromuscular examination and perfusion are normal. Therefore, the appropriate management would be to perform copious irrigation of the wound. This is important to clean the wound and remove any potential contaminants, reducing the risk of infection. Antimicrobial prophylaxis, tetanus booster immunization, tetanus toxoid in the wound, primary rabies vaccination, and examination of the dog's brain tissue for rabies are not necessary in this case.
37.
Aunt Mary is helping her family move to a new apartment. During the confusion, 3-year-old Jimmy is noted to be stumbling about, his face flushed and his speech slurred. The contents of Aunt Mary’s purse are strewn about on the floor. In the emergency room, Jimmy is found to have a rapid heartbeat, blood pressure of 42/20, and dilated pupils. ECG shows prolonged QRS and QT intervals. Jimmy suddenly starts to convulse. His condition is most likely to be the result of poisoning with:
Correct Answer
B. Tricyclic antidepressants
Explanation
Jimmy's symptoms, such as stumbling, flushed face, slurred speech, dilated pupils, rapid heartbeat, low blood pressure, and prolonged QRS and QT intervals on ECG, are consistent with tricyclic antidepressant poisoning. Tricyclic antidepressants can cause anticholinergic effects, including flushed face, dilated pupils, and dry mouth. They can also cause cardiovascular toxicity, leading to a rapid heartbeat and low blood pressure. Prolonged QRS and QT intervals on ECG are characteristic of tricyclic antidepressant overdose. Convulsions can also occur as a result of tricyclic antidepressant toxicity. Therefore, the most likely cause of Jimmy's condition is poisoning with tricyclic antidepressants.
38.
As a city public health officer, you have been charged with the task of screening high-risk children for lead poisoning. The best screen for this purpose is:
Correct Answer
D. Blood lead level
Explanation
The best screen for screening high-risk children for lead poisoning is a blood lead level test. Lead poisoning is primarily diagnosed by measuring the level of lead in the blood. This test provides a direct measurement of lead exposure and helps in identifying individuals who have been exposed to high levels of lead. Other screening methods mentioned, such as physical examination, erythrocyte protoporphyrin levels, CBC and blood smear, and environmental history, may provide additional information but are not as reliable or specific for detecting lead poisoning as the blood lead level test.
39.
Universal immunization of infants with a three-dose series of intramuscular, genetically engineered hepatitis B surface antigen vaccine is recommended. Implementation of this recommendation should decrease the incidence of which of the following?
Correct Answer
D. Hepatocellular carcinoma
Explanation
Implementation of universal immunization of infants with a three-dose series of hepatitis B vaccine is recommended in order to decrease the incidence of hepatocellular carcinoma. Hepatocellular carcinoma is a type of liver cancer that is commonly caused by chronic hepatitis B infection. By vaccinating infants against hepatitis B, the transmission of the virus can be significantly reduced, leading to a decrease in the incidence of hepatocellular carcinoma.
40.
New parents ask you how to reduce the chance of their baby suffering from sudden infant death syndrome (SIDS). You tell them to place the child in which of the following for sleep?
Correct Answer
A. Supine position
Explanation
The correct answer is supine position. Placing the baby on their back to sleep is recommended to reduce the risk of SIDS. This position helps to keep the airway open and decreases the chances of the baby rebreathing their own exhaled carbon dioxide. It is considered the safest sleeping position for infants and has been shown to significantly reduce the incidence of SIDS.
41.
A mentally retarded 14-year-old boy has a long face, large ears, micropenis, and large testes. Chromosome analysis is likely to demonstrate which of the following?
Correct Answer
D. Fragile X syndrome
Explanation
The given symptoms of a long face, large ears, micropenis, and large testes are characteristic features of Fragile X syndrome. This genetic disorder is caused by a mutation in the FMR1 gene on the X chromosome. Chromosome analysis in this case is likely to demonstrate an abnormality in the X chromosome, confirming the diagnosis of Fragile X syndrome. Trisomy 21, Trisomy 18, and Trisomy 13 are all associated with different chromosomal abnormalities and present with different clinical features. William syndrome is caused by a deletion of genetic material on chromosome 7 and does not match the symptoms described.
42.
A 5-month-old child presents to the emergency room with generalized tonic clonic seizure activity of about 30-min duration that stops upon the administration of lorazepam. The most helpful information to gather from the mother would be:
Correct Answer
C. Whether the mother has been diluting the infant’s formula to make it last longer
Explanation
The most helpful information to gather from the mother would be whether she has been diluting the infant's formula to make it last longer. This is because seizures in infants can be caused by electrolyte imbalances, and diluting formula can lead to decreased levels of important electrolytes such as sodium. This information would help determine if the seizure was caused by electrolyte abnormalities and guide further management.
43.
Many rashes and skin lesions can be found first in the newborn period. For each of the descriptions listed below, select the most likely diagnosis. A 1-week-old child’s mother complains that the child has a transient rash that has splotchy areas of erythema with a central clear pustule. Your microscopic examination of the liquid in the pustule reveals eosinophils. (SELECT 1 DIAGNOSIS)
Correct Answer
E. Erythema toxicum
Explanation
The description of a transient rash with splotchy areas of erythema and a central clear pustule, along with eosinophils seen on microscopic examination, is consistent with the diagnosis of erythema toxicum. Erythema toxicum is a common benign rash that appears in the first few days of life and resolves on its own without treatment. It is characterized by erythematous macules or papules with a central pustule, and eosinophils may be present in the pustule fluid.
44.
Many rashes and skin lesions can be found first in the newborn period. For each of the descriptions listed below, select the most likely diagnosis. An adolescent boy complains of a splotchy red rash on the nape of his neck, discovered when he had his head shaved for football season. The rash seems to get more prominent with exercise or emotion. His mother notes that he has had the rash since infancy, but that it became invisible as hair grew. He had a similar rash on his eyelids that resolved in the newborn period. (SELECT 1 DIAGNOSIS)
Correct Answer
B. Salmon patch
Explanation
The most likely diagnosis for the adolescent boy's splotchy red rash on the nape of his neck is a salmon patch. This is suggested by the fact that the rash has been present since infancy and became invisible as hair grew, indicating that it is a vascular birthmark that is more prominent when the area is shaved. The presence of a similar rash on his eyelids that resolved in the newborn period further supports this diagnosis.
45.
Many rashes and skin lesions can be found first in the newborn period. For each of the descriptions listed below, select the most likely diagnosis. A nurse calls you to evaluate an African American baby that seems to have a bacterial skin infection, with many scattered pustules full of a milky fluid. Upon examining a pustule, it easily wipes away, revealing a hyperpigmented spot. (SELECT 1 DIAGNOSIS)
Correct Answer
D. Pustular melanosis
Explanation
Pustular melanosis is the most likely diagnosis because it presents with pustules filled with milky fluid that easily wipe away, revealing a hyperpigmented spot. This condition is commonly seen in African American newborns and is considered a benign condition. Sebaceous nevi, salmon patch, neonatal acne, erythema toxicum, seborrheic dermatitis, and milia do not match the specific characteristics described in the question.
46.
Many rashes and skin lesions can be found first in the newborn period. For each of the descriptions listed below, select the most likely diagnosis. The obstetrical resident on call asks you to evaluate an area of a newborn’s scalp that seems to have no hair and is scaly and yellowish. (SELECT 1 DIAGNOSIS)
Correct Answer
A. Sebaceous nevi
Explanation
Sebaceous nevi are congenital skin lesions that typically appear as hairless, scaly, and yellowish patches on the scalp. This matches the description given in the question, making sebaceous nevi the most likely diagnosis.
47.
Many rashes and skin lesions can be found first in the newborn period. For each of the descriptions listed below, select the most likely diagnosis. A newborn’s mother complains that her infant seems to have very small white dots all over his nose. The dots do not wipe off with bathing, but they are also not erythematous. (SELECT 1 DIAGNOSIS)
Correct Answer
G. Milia
Explanation
Milia are small, white, pearly bumps that are commonly found on the nose and cheeks of newborns. They are caused by blocked oil glands and are not erythematous, meaning they are not red or inflamed. Milia do not wipe off with bathing and are a benign condition that usually resolves on its own within a few weeks.
48.
Many rashes and skin lesions can be found first in the newborn period. For each of the descriptions listed below, select the most likely diagnosis. A newborn’s father complains that his son has dandruff, with many waxy flakes of skin on the scalp. When he scrapes the lesions, hair often comes off with the flakes of skin. In addition, the baby has flaking of the eyebrows. (SELECT 1 DIAGNOSIS)
Correct Answer
F. Seborrheic dermatitis
Explanation
The given description of the newborn having dandruff-like flakes of skin on the scalp, flaking of the eyebrows, and hair coming off when the lesions are scraped is consistent with seborrheic dermatitis. Seborrheic dermatitis is a common skin condition in infants that causes flaky, oily, and yellowish scales on the scalp, eyebrows, and other areas of the body. The presence of these symptoms suggests that seborrheic dermatitis is the most likely diagnosis in this case.
49.
For each otherwise normal child presented, choose the sleep disturbance most consistent with the history. A 3-year-old boy awakens every night around 2:00 A.M. screaming incoherently. His parents note that he is agitated, seems awake but unresponsive, and goes back to sleep within a few minutes. He has no memory of the episodes in the morning.
Correct Answer
A. Night terrors
Explanation
The child's symptoms of awakening every night around the same time, screaming incoherently, appearing awake but unresponsive, and having no memory of the episodes in the morning are consistent with night terrors. Night terrors typically occur during non-REM sleep and are characterized by intense fear and agitation. The child's ability to go back to sleep within a few minutes also supports the diagnosis of night terrors, as individuals with nightmares often have difficulty falling back asleep.
50.
For each otherwise normal child presented, choose the sleep disturbance most consistent with the history. A 15-month-old toddler continues to wake up crying every night. Her parents give her a nighttime bottle, rock her, and sing to her to help her go back to sleep. Her parents are exhausted and ask you if she is having bad dreams.
Correct Answer
C. Learned behavior
Explanation
The toddler's consistent waking up and the parents' actions of giving her a bottle, rocking her, and singing to her suggest that her waking up crying every night is a learned behavior. This means that the toddler has associated these actions with falling back asleep and has learned to wake up and cry in order to receive them. It is not likely that she is having bad dreams or experiencing night terrors or nightmares, as those would typically involve more distress and fear upon waking up. Obstructive sleep apnea and somniloquy (sleep talking) are also less likely explanations in this case.