cLINICAL pEDIATRICS

Question 360: Clinical Pediatrics - Hereditary and Metabolic Disorders

Hypertrophic obstructive cardiomyopathy is the characteristic cause of death in Friedreich ataxia. Smaller numbers of patients may succumb to complications of diabetes. Lymphoma and other consequences of immunodeficiency occur at increased rates in ataxia-telangiectasia, another recessively inherited progressive ataxic syndrome. Respiratory failure and status epilepticus do not occur more commonly in Friedreich ataxia compared to the population at large.

Question 308: Clinical Pediatrics - Hereditary and Metabolic Disorders

Labhart-Prader-Willi presents with hypotonia, small size and usually poor feeding. A prolonged delivery with assistance required is quite common. Hyperphagia and secondary obesity occur later and can be partially corrected with dietary regulation and growth hormone supplementation. SMA I patients have absent reflexes. Patients with Sotos syndrome demonstrate macrocephaly, metachromatic leukodystrophy presents with absent or very diminished reflexes and may have Babinski signs, and Zellweger syndrome presents with very significant hepatomegaly.

Question 154: Clinical Pediatrics - Develop, Learn, Lang, Behav, Psych Disorders

Narcolepsy consists of a diagnostic tetrad that includes excessive daytime sleepiness, cataplexy, hypnagogic or hypnopompic hallucinations, and sleep paralysis. The most common presenting symptom in children is excessive daytime sleepiness, which in children and young adults may precede the development of cataplexy by several years. Diagnosis of narcolepsy is usually made when a positive multiple sleep latency test (MSLT) is found in individuals who experience both excessive daytime weakness and cataplexy.

Question 67: Clinical Pediatrics - Vascular and Inflammatory Disorders

Acute flaccid myelitis (AFM), characterized by acute weakness in >1 limb and either -a spinal cord lesion on MRl restricted to the gray matter spanning >1 spinal segments for a confirmed case or -a CSF pleocytosis of >5 white blood cells/mm3 for a probable case. Although AFM can occur at any age, most are younger than 21 years old. Asthma is one of the most common comorbidities. Many have a prodromal illness consisting of respiratory or gastrointestinal symptoms during week prior to the onset of neurological symptoms. The weakness shows an asymmetric, lower motor neuron pattern that commonly involves the arms proximally. At least 20% have cranial nerve involvement. Enterovirus D68 has been associated with AFM. Anti-aquaporin 4 antibodies may have a pathological role in neuromyelitis optica spectrum disorders. Elevated serum ferritin is one of the diagnostic criteria for hemophagocytic lymphohistiocytosis.

Question 304: Clinical Pediatrics - Epilepsy

Although any of these conditions may result in neurologic deterioration, epilepsy is not a prominent element of any of the conditions listed save for glucose transporter type I deficiency (DeVivo disease). Persistent and worsening seizures and encephalopathy are hallmarks of this disease due to energy failure, which can effectively be treated with the ketogenic diet.

Question 53: Clinical Pediatrics - Epilepsy

Benign occipital epilepsy (Panayiotopoulos syndrome) is one of the benign focal epilepsies of childhood; with a frequency about half of childhood epilepsy with centrotemporal spikes (CECTS). Autonomic symptoms predominate. In about one in five seizures the child will become flaccid and unresponsive (ictal syncope). Although considered an occipital epilepsy, the interictal EEG may not reveal occipital spikes and the ictal EEG onset may be posterior or anterior. Conventional seizures with eye deviation or motor manifestations also occur.

Question 131: Clinical Pediatrics - Headache/Other Paroxysmal Disorders

Benign paroxysmal torticollis is classified as a migraine equivalent by the International Headache Society. Some children go on to develop basilar-type migraines. Sandifer syndrome is posturing from esophageal discomfort and usually involves the trunk. Spasmus nutans has ocular oscillations along with head tilt and dopa-responsive dystonia (DRD) usually begins after 5 years of age, typically in the foot.

Question 165: Clinical Pediatrics - Develop, Learn, Lang, Behav, Psych Disorders

Both conditions may manifest ESES. By definition regressive autism occurs prior to three years of age, while the peak age of language loss with Landau-Kleffner syndrome is 5-7 years of age. Although behavioral and cognitive dysfunction may be found in Landau-Kleffner, these appear to be the result of language dysfunction, while they arise with equal primary significance in autistic regression. Prognosis for recovery is worse with earlier age of onset for both conditions. 75% of children with Landau-Kleffner manifest seizures, whereas convulsive seizures are far less common in children with autistic regression.

Question 185: Clinical Pediatrics - Epilepsy

Childhood Epilepsy with Centrotemporal Spikes (CECTS) is characterized by onset between 5 and 7 years of age nocturnal occurrence and benign interictal neurologic examination, and a characteristic EEG with independent Centro-temporal spikes with a horizontal dipole. It remits completely by adolescence in about 80% of patients, although other epileptic syndromes, including juvenile myoclonic epilepsy (JME), have been seen in some patients. Childhood absence remits in about two-thirds of children, although a few develop generalized convulsive epilepsy in adolescence or adulthood. JME often requires prolonged or indefinite treatment, with only about 20% remitting. Infants with prolonged febrile seizures followed by multiple seizure types are often manifesting Dravet syndrome and respond poorly to treatment. Lennox-Gastaut syndrome rarely remits and is often intractable.

Question 306: Clinical Pediatrics - Neurosurgery, Critical Care and Tumors

Eleven percent of pediatric brain tumors are pilocytic astrocytomas, and 80% are cystic. Medulloblastomas are rarely cystic, and glioblastoma multiforme is rare in this age group and in this location. Dandy-Walker malformations usually present in the first year of life. Cysticercosis in the posterior fossa most often presents extra-axially, and the enhancement is usually ring-like.

Question 61: Clinical Pediatrics - Neurosurgery, Critical Care and Tumors

Fever and irritability are seen in meningoencephalitis, but the characteristic presentation of spinal epidural abscess is a transverse myelopathy and a flexed posture resisting extension. This is a neurosurgical emergency. While infantile Guillain-Barre syndrome (AIDP) can present with bowel and bladder dysfunction, the posture and irritability would be unusual. Sandifer syndrome is not likely to have bowel and bladder symptoms, (Episodes of back twists and arches, postures brief , sudden, usually after baby eats. within the 1st. 2 yrs of life) and botulism would not present with fever, irritability or flexed posture.

Question 110: Clinical Pediatrics - Movement Disorders

GTP cyclohydrolase deficiency may produce abnormalities of tone and movement that result in a Parkinsonian syndrome. An additional diagnostic clue is the occurrence of repeated bouts of otherwise unexplained hyperthermia. Congenital disorder of glycosylation, cytochrome oxidase deficiency, multiple sulfatase deficiency, and succinic semialdehyde dehydrogenase deficiency do not have a prominent associated movement disorder.

Question 42: Clinical Pediatrics - Neonatal

Glycine encephalopathy (nonketotic hyperglycinemia) - frequent apnea, myoclonus, and burst suppression pattern on EEG. -Many mothers will note frequent "hiccups" of the fetus in utero, although this is often only elicited on specific questioning. -The diagnosis is made by CSF amino acids, typically compared to serum amino acids, where an elevated glycine level is seen, with an increased ratio of CSF:serum glycine. It can also be detected on intermediate echo MR spectroscopy. While MRI brain may demonstrate corpus callosal abnormalities, these are nonspecific. Very long chain fatty acids can be elevated in Zellweger syndrome and other peroxisomal disorders. Urine sulfites are increased in molybdenum cofactor and sulfite oxidase deficiency. Urine organic acids can determine some causes of neonatal encephalopathy and seizures, such as methylmalonic aciduria and maple syrup urine disease.

Question 126: Clinical Pediatrics - Neuromuscular

Nemaline myopathy has a static or slowly progressive course with rod-like inclusions on trichrome studies. Creatine kinase is normal or mildly elevated; EMG may be normal. The most common cause is a mutation in the alpha-actin gene. Fukuyama muscular dystrophy would not have the noted inclusions, nor would Mersin-deficient myopathy. Mitochondrial myopathy would show ragged red fibers. SMA type III would not present with a normal EMG

Question 39: Clinical Pediatrics - Neonatal

Neonatal encephalopathy from hypoxic-ischemia as in this case can injure the basal ganglia / thalamus, cerebral cortex, watershed cortex and white matter, or periventricular / central cerebral white matter. One predominant injury pattern involves the basal ganglia / thalamus, and the other involves the watershed areas. The basal ganglia / thalamus injury pattern occurs with sentinel events such as severe placental abruption. The watershed injury pattern occurs with partial, prolonged disruption of placental perfusion. Periventricular cerebral white matter injury, strokes, and intraventricular hemorrhages can occur hypoxic-ischemia encephalopathy but are less common and less likely in this clinical scenario.

Question 116: Clinical Pediatrics - Hereditary and Metabolic Disorders

Notably, the infant's head size is well below normal. Of the choices provided, only lissencephaly is associated with microcephaly and epileptic spasms. Perinatally acquired cytomegalovirus infection (CMV) is not generally associated with infantile spasms. Fragile X syndrome is usually not associated with infantile spasms. Tuberous sclerosis is frequently a cause of infantile spasms but is not generally associated with microcephaly. Aicardi syndrome generally does not occur in boys. The diagnosis of cryptogenic infantile spasms implies no other abnormalities are found, which is not consistent with severe microcephaly.

Question 37: Clinical Pediatrics - Infectious Disease

Of the causes of congenital infections listed (CMV, Rubella, HIV, Syphilis, and toxoplasmosis), toxoplasmosis is the most likely to manifest after delivery with liver abnormalities and obstructive hydrocephalus. The physical findings of hydrocephalus in a 1-month-old infant include prominent scalp veins and "sundown" eyes.

Question 332: Clinical Pediatrics - Headache/Other Paroxysmal Disorders

Pain may result in excessive vagal tone and bradycardia or asystole with ensuing pallid breath-holding. Cyanotic breath-holding is usually provoked by anger or frustration. Central hypoventilation syndrome is associated with sleep. Some occipital epileptic syndromes show light provocation. Paroxysmal choreoathetosis can be provoked by movement initiation. Paroxysmal torticollis is not usually emotionally or sensorially induced.

Question 93: Clinical Pediatrics - Cerebral Palsy

Prenatal or postnatal middle cerebral artery infarction is the most common cause of congenital hemiparesis. About 1/6000 uncomplicated live births have an arterial infarction. In most instances no clear etiologic factors can be identified. Children are usually normal at birth, although those with perinatal infarctions may manifest seizures, usually restricted to the hand. Far less commonly encountered etiologies include subdural hemorrhage, arteriovenous malformations, or hemimegalencephaly, and in such instances additional findings or a more eventful history are often encountered. Unilateral infantile venous sinus thrombosis is rare and is seldom an occult process.

Question 350: Clinical Pediatrics - Headache/Other Paroxysmal Disorders

The majority of children with recurrent headaches, with complete clearing between episodes, do not need neuroimaging. The following would mandate neuroimaging in a child presenting with headaches: 1-Auras lasting more than an hour 2-Persistent neurologic findings 3-Abnormal neurologic exam between headaches 4-Predominantly occipital headaches 5-Loss of vision at headache peak 6-Decline in cognitive function 7-Decline in growth velocity 8-or recent significant change in headache pattern.

Question 50: Clinical Pediatrics - Hereditary and Metabolic Disorders

The brief scenario describes a myopathic picture with a suggestion of an evolving neuropathy. Involvement of muscle is a characteristic feature of mitochondriopathies such as cytochrome oxidase type 1 deficiency, as is neuropathy. Congenital disorders of glycosylation would present with failure to thrive, ataxia, seizures, and cerebellar hypoplasia. Glucose transporter deficiency type 1 would present with difficult to control epilepsy. Glutaric aciduria presents with macrocephaly and metabolic crisis, usually in the context of an illness or other metabolic stress. Methylmalonic academia presents as a progressive encephalopathy, episodes of stroke, and hepatomegaly.

Question 318: Clinical Pediatrics - Develop, Learn, Lang, Behav, Psych Disorders

The combination of poor visuospatial skills, poor comprehension with good rote reading and memorization, and difficulty with peer relationships, at least partly due to inability to "read" faces, is typical for nonverbal learning disabilities. This is sometimes termed "right hemisphere learning disability," but anatomic localization is not clear. Angelman syndrome would be associated with epilepsy and poorer language function. Apraxia is associated with more motor difficulties. Dyslexia is associated with poor sight reading. Children with attention deficit hyperactivity disorder have difficulty with rote memory.

Question 324: Clinical Pediatrics - Neuromuscular

The congenital myasthenic syndromes are not related to an immune process but are caused by genetic defects affecting the neuromuscular junction. These include defects in acetylcholine synthesis and packaging (familial infantile myasthenia gravis), end-plate deficiency of acetylcholinesterase, acetylcholine receptor deficiency, and the slow channel syndrome.

Question 258: Clinical Pediatrics - Epilepsy

The lesion is a hypothalamic hamartoma. Typical presentation is gelastic epilepsy (seizures beginning with mirthless laughter). Endocrine effects are relatively uncommon, but precocious puberty may occur. None of the other seizure types described would be a consequence of a lesion in this location and with this appearance.

Question 341: Clinical Pediatrics - Neuromuscular

The patient described has a history concern for a glycogen storage disease, type V (GSD V), caused by an enzymatic defect on myophosphorylase encoded by PYGM on 11q13. This metabolic myopathy is characterized by exercise intolerance, myalgias, and muscle cramps. Patients can have myoglobinuria and rhabdomyolysis after extreme activity. Unlike other causes of episodic myoglobinuria, CK can remain elevated between episodes. EMG is typically normal, and forearm exercise test can be diagnostic. While the patient strenuously clenches and unclenches the hand, ammonia, lactate and pyruvate levels are obtained at multiple intervals. A normal response shows a 3 to 4-fold increase in ammonia, lactate and pyruvate from baseline, while patients with GSD V will have an appropriate rise in ammonia with no rise in lactate or pyruvate. Those with poor effort do not show a rise in any values. Patients with lactate dehydrogenase deficiency will have the expected rise of ammonia and pyruvate, but no rise in lactate. Finally, patients with fatty acid oxidation defects may or may not have myopathic motor unit potential and demonstrate a rise in lactate and pyruvate with no rise in ammonia.

Question 66: Clinical Pediatrics - Vascular and Inflammatory Disorders

The patient has a history and examination consistent with acute disseminated encephalomyelitis (ADEM). -Features of ADEM include a single polyfocal CNS event with a presumed demyelinating cause. -Lesions tend to be bilateral, and affect the deep grey structures and cortex. -It is typically preceded by an illness, or occasionally, immunizations. -Although ADEM is a diagnosis of exclusion, of the choices it is the most likely diagnosis. Acute cerebellar ataxia may also affect children of this age and be post-infectious. One would not expect encephalopathy, or the MRI lesions described with this diagnosis. In prepubertal children, anti-NMDA receptor encephalitis affects males and females equally, and may occur in the postinfectious setting. However, it is more frequently associated with movement disorder, seizures, and sleep disturbances at this age range. Leigh disease is a mitochondrial disorder, and while acute worsening can occur with infection, one would not expect typical development at this age of 4 years. Pediatric MS is equally predominant in prepubertal males and females. However, the distribution of lesions, presence of encephalopathy and lack of dissemination in both time and space makes this less likely.

Question 331: Clinical Pediatrics - Neonatal

The standard of care for neonates born at 36 weeks gestational age or older with neonatal encephalopathy from suspected or confirmed hypoxia-ischemia is 72 hours of therapeutic hypothermia at 33.5C. The eligibility criteria include having a gestational age of at least 35-36 weeks at birth, moderate to severe encephalopathy on exam, and at least one indicator of perinatal distress. Indicators of distress include an Apgar score below 5 at 10 minutes, an umbilical cord blood gas of less than 7.00 or base excess of -12 to -16 or more in the first hour of life, or more than 10 minutes of resuscitation. Therapeutic hypothermia should be implemented within the first 6 hours of life. The reduction in death or major neurodevelopmental disability with therapeutic hypothermia is about 25%.

Question 363: Clinical Pediatrics - Develop, Learn, Lang, Behav, Psych Disorders

The young woman has late juvenile metachromatic dystrophy, which presents as neuropsychiatric symptoms with relatively subtle motor signs, including her ataxia, incipient neuropathy, dysarthria, and long tract signs. Arylsulfatase A determination would confirm the diagnosis. Galactocerebrosidase deficiency (Krabbe disease) in its late juvenile form has more fulminant motor signs. A CMA is not likely to be helpful here, and a mitochondriopathy (lactate and pyruvate determinations) would not likely present in this fashion. Organic acidemias would likely present with metabolic crises after intercurrent illness, and not subacute neuropsychiatric disease.

Questions 196 - 200: Clinical Pediatrics - Cerebral Palsy

While kernicterus has become less common in developed countries due to monitoring of maternal Rh and ABO sensitization and neonatal bilirubin, it has not disappeared. In a home delivery without prenatal or neonatal medical supervision, risk is increased of maternal sensitization, unrecognized bilirubin encephalopathy, but also undetected inborn errors such as glutaric aciduria. Typical features of kernicterus are early hypotonia, followed by opisthotic posturing and later athetoid/dystonic Cerebral palsy with lack of vertical gaze, sensorineural hearing loss, but preserved intelligence. Infants with glutaric aciduria typically deteriorate markedly after a minor illness causing a catabolic state. Developed countries now test for glutaric aciduria on neonatal screening, but even with awareness of diagnosis and need to avoid fasting, patients may deteriorate abruptly or gradually. Pelizaeus-Merzbacher syndrome is associated with coarse nystagmus, lack of myelination diffusely on MRI. It can be either recessive or X-linked. Lesch-Nyhan syndrome is associated with severe self-injurious behavior and chorea, but onset is later than the perinatal period. Lesions of kernicterus may be inapparent on CT or even on MRI, but there may be cystic changes in globus pallidus with high signal on T2-weighted images. Juvenile Huntington disease more often presents with bradykinesia and dystonia, not usually chorea. MELAS and Kearns-Sayre syndrome may present with a variety of findings, but symmetric chorea or athetosis would be unusual. HIV encephalopathy, if untreated, typically causes loss of motor function, usually with spasticity as the major component. PKAN is generally characterized by progressive dystonia.

Question 80: Clinical Pediatrics - Neuromuscular

While weakness has multiple causes, the physical findings here are most consistent with dermatomyositis. A muscle biopsy would show perifascicular atrophy with sparing of the central fascicle, along with perivascular inflammation. The skin features would be unusual in a viral myositis, and Duchenne muscular dystrophy does not have such findings. Kawasaki disease would have other dermatologic manifestations. SLE would likely have a classic malar rash.