Endocrine/Neuro Flashcards
An 8-year-old girl is referred to her primary care provider by her dentist for evaluation of tongue and mouth lesions (Item Q7A and Item Q7B). Her mother recalls the lesions as being present for at least the past 3 years. They have not changed and are asymptomatic. The girl has no known medical problems. A review of systems is significant for intermittent constipation and diarrhea. No one in her family has similar lesions. Her weight is at the 25th percentile, and her height is at the 90th percentile. Her face is long and thin, and she has full lips. Her joints are hyperextensible, and pes planus is present. The remainder of her physical examination findings are unremarkable.
Of the following, the BEST next step is to evaluate for
A. an insulinoma
B. a medullary thyroid carcinoma C. an optic glioma D. a pheochromocytoma
a medullary thyroid carcinoma
Phenotypic features of multiple endocrine neoplasia type 2B include mucosal neuromas; a tall, thin body habitus; full lips; joint laxity; and alacrima. Gastrointestinal tract ganglioneuromas may cause intermittent constipation and diarrhea.
Multiple endocrine neoplasia type 2B is associated with early-onset and aggressive medullary thyroid carcinoma, in addition to pheochromocytoma and the physical phenotype.
It is important to recognize the clinical features of multiple endocrine neoplasia type 2B for timely prevention (prophylactic thyroidectomy), detection, and treatment of the associated medullary thyroid carcinoma.
MEN type 2A include hyperparathyroidism in addition to MTC and pheochromocytoma
A 12-year-old previously healthy, developmentally normal girl is seen in the office after an emergency department visit for a first-time seizure. The previous evening her mother heard a thud and found her daughter on the bedroom floor shaking, with her eyes open and rolled back. This lasted for about 2 minutes after which she fell asleep. Her mother called 911 immediately after the shaking ended. On arrival at the emergency department, the girl’s physical examination findings and laboratory results were normal, including a complete blood cell count, bedside glucose level, comprehensive metabolic panel, and serum and urine toxicology screen. She was discharged after several hours of observation.
In the office, the girl and her mother report no prior history of paroxysmal events, family history of seizures or epilepsy, and no recent medication changes. The girl denies drug or alcohol use. Findings of her physical examination, including vital signs, and neurologic examination are normal
Of the following, the BEST next step in this girl’s diagnostic evaluation would be
A. computed tomography of the head B. electroencephalography C. electrocardiography D. magnetic resonance imaging of the brain
EEG
In first-time unprovoked seizure cases, electroencephalography is a key part of the diagnostic evaluation for evidence of abnormalities in support of a seizure tendency (epilepsy), specific epilepsy syndrome, and to guide further diagnostic and therapeutic management.
Seizure is a clinical diagnosis; the history and physical examination are critical for diagnosis and appropriate care
For children with status epilepticus, focal seizure, postictal paralysis, lack of return to baseline condition, or newly abnormal neurologic examination, computed tomography of the head may be appropriate to assess for acute neurologic conditions such as hemorrhage, mass, or hydrocephalus. In such cases, brain magnetic resonance imaging (MRI) may be considered; MRI provides a detailed structural image, allowing for evaluation of brain malformations, mass lesions, ischemic stroke, or demyelination.
A female neonate born at term is evaluated in the neonatal intensive care unit. The pregnancy was complicated by maternal gestational diabetes and alcohol exposure. Prenatal ultrasonography at 20 weeks showed intrauterine growth retardation. The neonate is presently intubated. Her birth weight is 2,200 g. She has a small jaw, clenched hands with overlapping fingers (Item Q16), rocker-bottom feet, a short sternum, and hypoplastic nails. Echocardiography shows a ventricular septal defect. Renal ultrasonography shows a horseshoe kidney.
Of the following, the MOST likely diagnosis is
A. fetal alcohol spectrum disorder
B. trisomy 13
C. trisomy 18 D. trisomy 21
Trisomy 18 / Edwards
Trisomy 18 is characterized by distinctive dysmorphic features: clenched hands with overlapping fingers, rocker-bottom feet, and short sternum.
More Details: intrauterine growth retardation and by congenital cardiac, ocular, and renal anomalies. Dysmorphic features include small jaw, clenched hands with overlapping fingers (index overlapping the third, fifth overlapping the fourth), short sternum, and hypoplastic nails.
Trisomy 13 and trisomy 18 can both manifest in failure to thrive and congenital anomalies.
Trisomy 13 is characterized by midline and scalp defects and rocker-bottom feet.
More details: scalp defect called “cutis aplasia” and midline defects such as holoprosencephaly and cleft lip, cleft palate
A 14-year-old adolescent boy is seen for a sports preparticipation physical examination. He and his mother are concerned about his small size. He has no known medical problems and takes no medication. A comprehensive review of systems is unremarkable. His mother is 165 cm tall and had menarche at age 12 years. His father is 178 cm tall and completed his linear growth while in college. His 12-year-old sister is taller than he is at 157 cm and recently had menarche. His growth chart is shown in Item Q26. His body mass index is 17.3 kg/m2 (18th percentile). His vital signs are normal for age. He appears younger than his chronological age. His sexual maturity rating is 1 for pubic hair and genital development. His testicular volume is 3 mL bilaterally. The remainder of his physical examination findings are normal. A bone age radiograph has a result of 11 years.
Laboratory data are shown:
Laboratory Test
Result
Luteinizing hormone
0.4 IU/L (0.4 IU/L) (reference rangea, < 0.1-0.3 IU/L)
Follicle-stimulating hormone
2.4 IU/L (reference rangea, 0.26-3 IU/L)
Testosterone
15 ng/dL (0.5 nmol/L) (reference rangea,
< 2.5-10 ng/dL [0.09-0.4 nmol/L])
a Reference ranges are for individuals with a sexual maturity rating of 1.
Of the following, the BEST next step is
A. advising the patient to increase the calories in his diet
B. brain magnetic resonance imaging
C. referral for consideration of growth hormone therapy D. referral for consideration of testosterone therapy
referral for consideration of testosterone therapy
Constitutional delay of puberty is the most common cause of delayed puberty, especially in boys.
Constitutional delay of puberty in boys with associated psychosocial distress is an indication for a short course of testosterone to accelerate pubertal development and promote earlier initiation of the pubertal growth spurt.
A short course of a testosterone ester intramuscularly once per month for 3 to 4 months can accelerate pubertal development and promote earlier initiation of the pubertal growth spurt.
Puberty is considered delayed in boys when there is a lack of testicular growth = 4 mL in volume (or 2.5 cm in length) by age 14 years. In girls, puberty is delayed when there is a lack of breast development by age 13 years.
Bone age is delayed and during adolescence more closely matches the pubertal stage than chronological age. He likely has a family history of constitutional delay, because his father completed his own linear growth in college
his biochemical profile shows evidence of early activation of the hypothalamic-pituitary-gonadal axis, with a luteinizing hormone and testosterone level just above the normal range for a male with a sexual maturity rating of 1. These levels make hypogonadotropic hypogonadism unlikely
A 15-year-old adolescent is seen in the office for evaluation of recurrent headaches for the past 5 years. Her headaches are described as a bifrontal throbbing pain with associated photophobia, phonophobia, nausea, and vomiting. She feels fatigued and experiences visual distortions with sparkling lights before headache onset. Her headaches occur approximately once weekly and respond to appropriately dosed nonsteroidal anti-inflammatory drugs (NSAIDs). The girl misses school approximately once per semester because of her headaches. She denies waking at night with headache, initiation of headache with valsalva maneuver, or associated focal neurologic deficit. No triggers have been identified. Her neurologic examination findings in the office are normal. Fundoscopy reveals sharp disc margins with no evidence of papilledema. Magnetic resonance imaging of the brain, performed 3 years earlier, was normal.
Of the following, in addition to continued use of NSAIDs, the BEST next management step for this girl is
A. initiation of vitamin therapy B. initiation of prophylactic medication C. initiation of triptan D. lifestyle trigger identification and modification
lifestyle trigger identification and modification
Migraine headaches are moderately severe, episodic, pulsatile pain events with associated photophobia, phonophobia, nausea, and vomiting.
Migraine management includes 3 components: abortive medications, preventive medications, and lifestyle management.
Trigger identification and lifestyle management form the foundation of migraine care.
Concerning features, such as age less than 6 years, waking at night with headache, initiation of headache with valsalva maneuver, or associated focal neurologic deficit, would indicate a need for additional investigation
medication overuse, this becomes a risk when using acetaminophen or NSAIDs more than 14 days in a month and triptans more than 9 days in a month.
A 4-month-old infant is seen for evaluation of excessive tearing and blinking since birth. His parents report wiping clear discharge from his eyes and nares multiple times per day. He blinks often and prefers to keep his eyes closed when exposed to bright lights. There has been no fever, eye redness, eye swelling, yellow eye discharge, or cough. He is afebrile and in the 50th percentile for weight and height. On eye examination, he does not fixate on objects or track. There is no periorbital edema or erythema, and his conjunctivae and sclerae are clear. He has bilateral clear discharge, opaque red reflexes, and mild corneal clouding.
Of the following, the MOST likely diagnosis for this infant is
A. acute dacryocystitis B. cataract C. glaucoma D. nasolacrimal duct obstruction
Glaucoma
Every newborn should be evaluated with red reflex testing and Brückner reflex testing before discharge and at each health supervision visit.
Prompt recognition and management of congenital glaucoma is crucial for prevention of blindness.
The classic presentation of congenital or early-onset glaucoma is corneal clouding, photophobia, and chronic or intermittent tearing.
Primary congenital, infantile, and juvenile glaucoma are rare; secondary glaucoma may develop in the setting of Sturge-Weber syndrome, aniridia, or retinopathy of prematurity or as a consequence of cataract surgery, tumors, trauma, or exposure to steroids.
A 9-year-old boy is seen for a routine follow-up for asthma that was diagnosed at age 3 years. He has been treated with inhaled corticosteroids since the time of diagnosis. His current medications include mometasone furoate 100 μg with formoterol fumarate 5 μg two inhalations twice daily, fluticasone propionate one spray in each nostril daily, and albuterol two puffs inhaled every 4 hours as needed for cough, shortness of breath, or wheeze. His asthma has been well controlled since his inhaled corticosteroid therapy was intensified 3 years ago. His last asthma exacerbation and last course of oral corticosteroids was more than 1 year ago. His vital signs are normal for his age. His growth chart is shown in Item Q66. His body mass index is 15.9 kg/m2 (40th percentile). Examination of his respiratory system yields normal findings. The remainder of his physical examination findings are unremarkable.
Of the following, the MOST likely cause of this boy’s physical findings is
A. constitutional delay of growth
B. exogenous glucocorticoid
C. growth hormone deficiency
D. pituitary adenoma
exogenous glucocorticoid
The most common cause of Cushing syndrome is exogenous glucocorticoid.
Excess glucocorticoid acquired by any route can have a profound effect on linear growth.
Suppression of the hypothalamic-pituitary-adrenal axis by excess glucocorticoid acquired by any route can cause an adrenal crisis during times of stress.
Cushing syndrome is characterized by weight gain, centripetal obesity, linear growth failure, violaceous striae, and osteopenia
Options for initial testing for hypercortisolism include a 24-hour urine free cortisol test, a low-dose (1-mg) overnight dexamethasone suppression test, or a midnight salivary cortisol test. Positive test findings should be confirmed with a second measurement. A morning cortisol level that fails to suppress after administration of low-dose dexamethasone the night before is consistent with hypercortisolism.
ACTH level, a high-dose dexamethasone suppression test, and pituitary or adrenal imaging as indicated. Cortisol levels are suppressed after administration of high-dose dexamethasone with an ACTH-dependent pituitary source of Cushing but not with adrenal source
A 15-year-old adolescent is brought to the emergency department for a new-onset generalized tonic-clonic seizure that occurred while asleep. She was having a sleepover party and had stayed up until 3 am. Around 7 am, her friend found her unresponsive with generalized shaking, her eyes rolled up and open, and foaming at the mouth. The event lasted approximately 2 minutes before self-resolving.
On arrival at the emergency department, the girl is drowsy but arousable. She has otherwise normal neurologic findings. Her mother reports that the adolescent has had several episodes of staring spells over the past few years which she attributed to her daughter ignoring her. Over the past year, she has periodically complained of “spasms” where her hand will suddenly jump or jerk. She denies substance use, recent or intercurrent illnesses, or trauma. There is no family history of seizures.
Of the following, the MOST likely diagnosis is
A. benign focal epilepsy of childhood B. juvenile absence epilepsy C. juvenile myoclonic epilepsy D. progressive myoclonic epilepsy
juvenile myoclonic epilepsy
Juvenile myoclonic epilepsy is a lifelong genetic generalized epilepsy presenting in early adolescence with myoclonus, generalized tonic-clonic, and/or absence seizures; seizures often occur in the morning.
Seizures in juvenile myoclonic epilepsy can be provoked by sleep deprivation, photic stimulation, alcohol consumption, or stress.
Benign rolandic epilepsy (benign focal epilepsy of childhood) is the most common childhood epilepsy. It typically presents between 5 and 10 years of age and resolves by adolescence.
he history should include questions about early morning clumsiness, jitteriness, or dropping objects.
A 4-year-old boy (Item Q76) is seen for a health supervision visit. He was born at full term to a 35-year-old mother. The mother reports that at age 30 years she underwent fertility treatments because of premature ovarian failure. The boy has delayed speech and can say only 10 words. He is very active and runs around the room during the entire visit. The mother expresses concern about his behavior, frequent temper tantrums, hand flapping, and biting his 2-year-old sister. The family history is significant for bipolar disorder in the maternal grandmother and Parkinson disease in the maternal grandfather. The family history on the paternal side is unknown.
Of the following, the MOST likely underlying etiology of this boy’s clinical disorder is
A. CAG repeats in HTT B. CGG repeats in FMR1 C. CTG repeats in DMPK D. GAA repeats in FXN
CGG repeats in FMR1
Fragile X syndrome is caused by expansion of CGG repeats in the FMR1 gene.
Fragile X syndrome is the most common cause of X-linked intellectual disability.
Both male and female premutation carriers are at increased risk of experiencing fragile X–associated tremor/ataxia syndrome. Female premutation carriers are at increased risk of experiencing premature ovarian failure.
facial profile with long face, prominent forehead, prominent jaw, and large ears. Macroorchidism can be seen in postpubertal males
fragile X–associated tremor/ataxia syndrome, which is characterized by progressive cerebellar ataxia with intention tremor
A 2-year-old girl with mild global developmental delay and refractory epilepsy is placed on a ketogenic diet for management of her seizures. She experiences improved seizure control and is followed closely by a pediatric epileptologist and dietician. Her mother brings her for her health supervision visit and states that overall the girl is tolerating the diet well with mild constipation and is taking her multivitamin with calcium and vitamin D supplements daily. Her mother states that she understands that the diet can have other side effects and asks if the girl should be monitored for additional complications.
Of the following, the girl is MOST at risk for
A. carnitine deficiency B. kidney stones C. osteopenia D. zinc deficiency
kidney stones
The ketogenic diet can be effective in the management of children with medically refractory epilepsy. With initiation of the diet, half of children show a 50% or more reduction in seizure burden independent of epilepsy type or electroencephalographic findings.
Common adverse events of the ketogenic diet include gastrointestinal complaints, hyperlipidemia, and kidney stones.
Carbohydrate-free multivitamin, calcium, and vitamin D supplementation is recommended to prevent vitamin and mineral deficiencies, and the development of osteopenia.
While on a ketogenic diet, a screening urinary calcium-to-creatinine ratio measurement is recommended every 3 months
A 4-year-old boy is seen for a health supervision visit. He has eczema and has had recurrent ear infections that required the placement of myringotomy tubes. He attends preschool, knows his letters, and can draw a triangle and a square. He is interactive during the physical examination. His height is at the 30th percentile, his weight is at the 50th percentile, and his head circumference is at the 70th percentile. He can hop on one foot for 2 seconds and sing his favorite nursery rhyme. His mother reports that his father, paternal uncle, and grandmother have short stature, a large head, small fingers, and shortening of both arms and thighs. His father has been relatively healthy except for obstructive sleep apnea. His grandmother had stenosis of the lumbar spine and hearing loss. His uncle recently had a newborn son with a large head and short limbs who underwent ventriculoperitoneal shunt insertion because of obstructive hydrocephalus.
Of the following, the inheritance pattern of the disorder MOST likely seen in this family is
A. autosomal dominant with complete penetrance
B. autosomal dominant with incomplete penetrance
C. X-linked dominant
D. X-linked recessive
autosomal dominant with complete penetrance
Achondroplasia is characterized by disproportionate short stature with rhizomelic shortening, macrocephaly, and facial features of frontal bossing and midface retrusion.
The inheritance pattern of achondroplasia is autosomal dominant with complete penetrance.
Complications of the disorder include a risk of increased intracranial pressure owing to obstructive hydrocephalus, craniocervical junction compression, obstructive sleep apnea, conductive hearing loss, persistent kyphosis, and spinal stenosis (in adults).
A 6-year-old girl is seen by her pediatrician after failing a school vision screening. A subsequent evaluation by an ophthalmologist reveals no vision in the right eye and bilateral optic disk atrophy. She is referred to the emergency department. She has no significant medical history. She appears well and in no distress. Her height is at the first percentile, and her weight is at the seventh percentile. A growth chart provided by her mother shows that she was at the 15th percentile for height 1 year ago. She has a temperature of 37.1°C, a heart rate of 92 beats/min, a blood pressure of 108/78 mm Hg, a respiratory rate of 22 breaths/min, and an oxygen saturation of 98% on room air. Other than a complete lack of discernible vision in her right eye, the examination findings are unremarkable. Findings from emergent magnetic resonance imaging are shown (Item Q100 ).
Of the following, the MOST likely outcome after initial treatment is
A. panhypopituitarism requiring lifelong hormone replacement
B. progression to herniation and respiratory failure
C. progressive loss of vision, gradually resulting in blindness
D. recurrent, metastatic disease refractory to therapy
panhypopituitarism requiring lifelong hormone replacement
Children with craniopharyngiomas frequently experience central hypothyroidism, hypocortisolism, hypogonadism, growth hormone deficiency, and diabetes insipidus, all of which require hormone replacement.
Craniopharyngiomas treated with complete resection or partial resection and radiation tend to not recur, and they very rarely metastasize.
Large pituitary tumors can compress the optic chiasm, resulting in bilateral vision loss.
A 10-year-old girl with type 1 diabetes is seen for decreased appetite and fatigue over the past month. She eats three meals per day, but she consumes small portions because of nausea. She has not had abdominal pain, vomiting, diarrhea, constipation, or recent illness. Her diabetes is treated with rapid-acting insulin via an insulin pump. She has had a 2.3-kg weight loss since her last health supervision visit 4 months ago. Her vital signs and the remainder of her physical examination findings are normal. Her most recent hemoglobin A1c level was 7.9% 2 months ago. Today, her hemoglobin level is 10 g/dL (100 g/L) with a mean corpuscular volume of 72 fL.
Of the following, the MOST likely underlying diagnosis causing this girl’s symptoms is
A. adrenal insufficiency B. celiac disease C. hypothyroidism D. inflammatory bowel disease
celiac disease
Autoimmune thyroid disease, usually hypothyroidism, is the autoimmune condition most commonly associated with type 1 diabetes.
Celiac disease is the autoimmune condition second most commonly associated with type 1 diabetes.
Guidelines recommend routine screening for thyroid disease and celiac disease in patients with type 1 diabetes at the time of diagnosis of diabetes and periodically thereafter.
These symptoms include decreased appetite, fatigue, nausea, weight loss, and microcytic anemia
A 7-year-old girl is seen for a health supervision visit. Her mother is concerned that she is the smallest child in her class. The girl’s medical history is significant for placement of ear tubes at age 2 years because of multiple episodes of acute otitis media. She takes no medication. She is generally doing well in the second grade but requires extra help in math. A comprehensive review of systems is otherwise unremarkable. Her adjusted midparental height is 164 cm (50th percentile for an adult female), and pubertal timing for both parents was normal. Vital signs are normal for age. Her growth chart is shown in Item Q147. Her body mass index is 15.4 kg/m2 (50th percentile). The physical examination findings are unremarkable. A bone age radiograph is read as concordant with her chronological age.
Of the following, the test MOST likely to lead to this girl’s diagnosis is
A. insulin-like growth factor-1
B. a karyotype
C. thyroid-stimulating hormone
D. tissue transglutaminase IgA antibody
a karyotype
Short stature is the most common manifestation of Turner syndrome and may be the only presenting feature.
Normal versus abnormal height velocity, body mass index, and bone age are important factors to consider in narrowing the differential diagnosis of short stature.
Features of Turner syndrome displayed by the girl in the vignette include her short stature with declining growth velocity, recurrent otitis media, and difficulty with math.
Other common features include ptosis; epicanthal folds; low-set, prominent ears; high-arched palate; neck webbing; low posterior hairline; broad chest with wide-spaced nipples; multiple nevi; congenital heart disease (eg, coarctation of the aorta); renal anomalies (eg, horseshoe kidney); skeletal anomalies (scoliosis, shortened 4th metacarpals, high upper-to-lower segment ratio); and primary ovarian failure.
Declining growth velocity can be consistent with an endocrine disorder such as growth hormone deficiency or hypothyroidism. Bone age, however, would be delayed in these endocrine disorders. For nutritional disorders, gastrointestinal disorders, and other chronic systemic disease, weight is usually affected before height or more than height (so that body mass index is relatively low), and bone age would be expected to be delayed.
A 31-month-old boy is seen in the office for a growth check. He was born at term. The delivery was complicated by excessive hemorrhage. He has been healthy and takes a daily multivitamin. A comprehensive review of systems is unremarkable. His adjusted midparental height is at the 40th percentile. His growth charts are shown in Item Q226A and Item Q226B. His vital signs are normal for age, and his physical examination findings are unremarkable.
Laboratory data are shown:
Laboratory Test
Result
White blood cell count
8,300/μL (8.3 × 109/L)
Hemoglobin
13 g/dL (130 g/L)
Platelet count
281 × 103/μL (281 × 109/L)
Sodium
138 mEq/L (138 mmol/L)
Potassium
4.1 mEq/L (4.1 mmol/L)
Bicarbonate
25 mEq/L (25 mmol/L)
Creatinine
0.3 mg/dL (26.5 µmol/L)
Glucose
90 mg/dL (5.0 mmol/L)
Thyroid-stimulating hormone
1.4 mIU/L (reference range, 0.27-4.2 mIU/L)
Free thyroxine
1.3 ng/dL (17 pmol/L) (reference range, 0.9-1.7 ng/dL [12-22 pmol/L])
Urinalysis findings are normal except for a specific gravity of 1.020 and a pH of 6.
Of the following, the MOST likely diagnosis is
A. celiac disease B. growth hormone deficiency C. insufficient caloric intake D. renal tubular acidosis
growth hormone deficiency
In those with congenital growth hormone deficiency, linear growth becomes abnormal at about the age of 6 to 12 months.
Patients with acquired growth hormone deficiency should undergo investigation for a brain neoplasm and other pituitary hormone deficiencies.
The weight-for-length or body mass index curve is important to consider in narrowing the differential diagnosis of abnormal growth.
The history of excessive hemorrhage at the time of delivery is a risk factor for growth hormone deficiency resulting from a vascular injury to the pituitary gland. Of the pituitary hormones, growth hormone is the most sensitive to pituitary insults.
The presence of nystagmus and midline defects suggests septo-optic dysplasia. Males can have a small penis, cryptorchidism, or both, especially if concomitant gonadotropin deficiency is present.
