GENERAL PEDIATRICS

NUTRITION

100

Clinical features often seen in overweight pediatric patients can include all of the following EXCEPT: A.Delayed puberty B.Acanthosis nigricans C.Hypertension D.Snoring and poor sleep E.Orthopedic complaints including hip and knee pain

What is Delayed puberty Tanner staging can reveal premature adrenarche secondary to advanced sexual maturation in overweight and obese girls.

200

The groups with the highest risk of obesity in the USA are: A. White males B. White females C. African-American and Hispanic males D. African-American females and Hispanic males E. Asian-American males and females

What is African-American females and Hispanic males A child's risk varies by socioeconomic status, race, maternal education level, and gender. African-American adolescent girls and Mexican-American 6-12 yr old boys have higher rates of obesity compared with other groups. Childhood obesity also is increasingly common in some Native American groups

300

Which of the following clinical scenarios increases the risk of vitamin A deficiency? A. Vegetarian diet B. Chronic intestinal disorders C. Zinc deficiency D. B and C E. All of the above

What is B and C Vitamin A is an essential micronutrient because it cannot be biogenerated de novo by animals. It must be obtained from plants in the form of provitamin-A carotenoids. In the USA, grains and vegetables supply approximately 55% and dairy and meat products supply approximately 30% of vitamin A intake from food. Vitamin A and the provitamins-A are fat soluble, and their absorption depends on the presence of adequate lipid and protein within the meal. Chronic intestinal disorders or lipid malabsorption syndromes can result in vitamin A deficiency. In developing countries, subclinical or clinical zinc deficiency can increase the risk of vitamin A deficiency. There is also some evidence of marginal zinc intakes in children in the USA.

400

Which of the following patients is at risk for thiamine deficiency? A. Exclusively breast-fed infant, mother is well-nourished B. 2 yr old immigrant fed a vegetarian diet C. 3 yr old refugee whose dietary staple is polished rice D. 4 yr old American boy who eats only breakfast cereal E. All of the above

What is 3 yr old refugee whose dietary staple is polished rice Pork (especially lean), fish, and poultry are good nonvegetarian dietary sources of thiamine. Main sources of thiamine for vegetarians are rice, oat, wheat, and legumes. Most ready-to-eat breakfast cereals are enriched with thiamine. Thiamine is water soluble and heat labile; most of the vitamin is lost when the rice is repeatedly washed and the cooking water is discarded. The breast milk of a well-nourished mother provides adequate thiamine; breast-fed infants of thiamine-deficient mothers are at risk for deficiency. Most infants and older children consuming a balanced diet obtain an adequate intake of thiamine from food and do not require supplements. Deficiency of thiamine is associated with severely malnourished states, including malignancy and following surgery. The disorder is classically associated with a diet consisting largely of polished rice (oriental beriberi); it can also arise if highly refined wheat flour forms a major part of the diet, in alcoholics, and in food faddists (occidental beriberi).

500

Which statement about vitamin E is false? A. The most common form of vitamin E is tocopherol B. Premature infants given formula with a high content of polyunsaturated fatty acids and iron supplementation are protected from deficiency C. Cholestatic liver disease increases the risk of deficiency D. Premature infants with vitamin E deficiency develop hemolysis, thrombocytosis, and edema E. Prolonged vitamin E deficiency causes a severe, progressive neurologic disorder

What is Premature infants given formula with a high content of polyunsaturated fatty acids and iron supplementation are protected from deficiency Premature infants are particularly susceptible to vitamin E deficiency because there is significant transfer of vitamin E during the last trimester of pregnancy. Vitamin E deficiency in premature infants causes thrombocytosis, edema, and hemolysis, potentially causing anemia. The risk of symptomatic vitamin E deficiency was increased by the use of formulas for premature infants that had a high content of polyunsaturated fatty acids (PUFAs). These formulas led to a high content of PUFAs in red blood cell membranes, making them more susceptible to oxidative stress, which could be ameliorated by vitamin E. Oxidative stress was augmented by aggressive use of iron supplementation; iron increases the production of oxygen radicals. The incidence of hemolysis due to vitamin E deficiency in premature infants decreased secondary to the use of formulas with a lower content of polyunsaturated fatty acids, less-aggressive use of iron, and provision of adequate vitamin E.

INFECTIONS

100

A 16 yr old girl experiences abrupt onset of high fever, vomiting, and diarrhea, with a diffuse sunburn-like rash, hyperemia of the pharyngeal and conjunctival membranes, oliguria, and postural hypotension. The most likely diagnosis is: A. Hemolytic-uremic syndrome B. Kawasaki disease C. Rocky Mountain spotted fever D. Toxic shock syndrome (TSS) E. Stevens-Johnson syndrome

What is Toxic shock syndrome (TSS) The diagnosis of TSS is based on clinical manifestations. The onset is abrupt, with high fever, vomiting, and diarrhea and is accompanied by sore throat, headache, and myalgias. A diffuse erythematous macular rash (sunburn-like or scarlatiniform) appears within 24 hr and may be associated with hyperemia of pharyngeal, conjunctival, and vaginal mucous membranes. A strawberry tongue is common. Symptoms often include alterations in the level of consciousness, oliguria, and hypotension, which in severe cases may progress to shock and disseminated intravascular coagulation. Complications, including acute respiratory distress syndrome, myocardial dysfunction, and renal failure, are commensurate with the degree of shock. Recovery occurs within 7-10 days and is associated with desquamation, particularly of palms and soles; hair and nail loss have also been observed after 1-2 mo.

200

All of the following are features of scarlet fever EXCEPT: A. An erythematous, popular eruption with perioral pallor B. Desquamation C. White strawberry tongue D. Red strawberry tongue E. Preauricular lymphadenopathy

What is Preauricular lymphadenopathy The rash appears within 24-48 hours after onset of symptoms, although it may appear with the 1st signs of illness. It often begins around the neck and spreads over the trunk and extremities. It is a diffuse, finely papular, erythematous eruption producing a bright red discoloration of the skin, which blanches on pressure. It is often more intense along the creases of the elbows, axillae, and groin. The skin has a goose-pimple appearance and feels rough. The face is usually spared, although the cheeks may be erythematous with pallor around the mouth. After 3-4 days, the rash begins to fade and is followed by desquamation, first on the face, progressing downward, and often resembling a mild sunburn. Occasionally, sheetlike desquamation may occur around the free margins of the fingernails, the palms, and the soles. Examination of the pharynx of a patient with scarlet fever reveals essentially the same findings as with GAS pharyngitis. In addition, the tongue is usually coated and the papillae are swollen. After desquamation, the reddened papillae are prominent, giving the tongue a strawberry appearance

300

Which of the following is not one of the major criteria (Jones criteria) for rheumatic fever? A. Carditis B. Polyarthritis C. Erythema chronicum migrans D. Subcutaneous nodules E. Sydenham chorea

What is Erythema chronicum migrans There are 5 major criteria: carditis, polyarthritis, erythema marginatum, subcutaneous nodules, and chorea

400

A 26 mo old child with sickle cell disease appears in your office for the 1st time. He has a history of a prior hospitalization for pneumococcal bacteremia. Currently the child is on penicillin prophylaxis, but he has not received either the conjugate or polysaccharide pneumococcal vaccine. Which of the following is the optimal means for protecting this child from developing another episode of invasive pneumococcal disease? A. Give 1 dose of the pneumococcal conjugate vaccine and continue penicillin prophylaxis B. Give 1 dose of the pneumococcal polysaccharide vaccine and continue penicillin prophylaxis C. Give 1 dose of the pneumococcal conjugate vaccine followed 1 month later by one dose of the pneumococcal polysaccharide vaccine and continue penicillin prophylaxis D. Give 1 dose of the pneumococcal conjugate vaccine and switch from penicillin prophylaxis to Augmentin prophylaxis E. Give 1 dose of pneumococcal conjugate vaccine and switch to intramuscular benzathine penicillin prophylaxis

What is What is Give 1 dose of the pneumococcal conjugate vaccine followed 1 month later by one dose of the pneumococcal polysaccharide vaccine and continue penicillin prophylaxis Immunization with PCV13 is recommended for all infants on a schedule for primary immunization, in previously unvaccinated infants, and for transition for those partially vaccinated with PCV7 (Tables 175-3 and 175-4). High-risk children ≥ 2 yr of age, such as those with asplenia, sickle cell disease, some types of immune deficiency (e.g., antibody deficiencies), HIV infection, cochlear implant, CSF leak, diabetes mellitus, and chronic lung, heart, or kidney disease (including nephrotic syndrome), may benefit also from PPSV23 administered after 2 yr of age following priming with the scheduled doses of PCV13. Thus, it is recommended that children ≥ 2 yr of age with these underlying conditions receive supplemental vaccination with PPSV23. A 2nd dose of PPSV23 is recommended 5 yr after the 1st dose of PPSV23 for persons aged ≥ 2 yr who are immunocompromised, have sickle cell disease, or functional or anatomic asplenia.

500

Which of the following is associated with a poorer prognosis for persons presenting with meningococcal disease? A. Presence of petechiae for < 12 hr B. Meningitis C. Thrombocytosis D. Leukocytosis E. High ESR

What is Presence of petechiae for < 12 hr The mortality rate for invasive meningococcal disease remains about 10% in the USA despite modern medical interventions. Most deaths occur within 48 hr of hospitalization in children with meningococcemia. Poor prognostic factors on presentation include hypothermia or extreme hyperpyrexia, hypotension or shock, purpura fulminans, seizures, leukopenia, thrombocytopenia (including DIC), acidosis, and high circulating levels of endotoxin and TNF-α. The presence of petechiae for < 12 hr before admission, absence of meningitis, and low or normal ESR indicate rapid, fulminant progression and poorer prognosis.

ANOMALIES/ SYNDROMES

100

Clinical manifestations of a cleft lip or palate may include: A. Palpable notch at the posterior of the palate B. Deficiencies of the nasal alar cartilage C. Bifid uvula D. Notching of the vermilion border E. All of the above

What is All of the above Cleft lip can vary from a small notch in the vermilion border to a complete separation involving skin, muscle, mucosa, tooth, and bone. Clefts may be unilateral (more often on the left side) or bilateral and can involve the alveolar ridge. Isolated cleft palate occurs in the midline and might involve only the uvula or can extend into or through the soft and hard palates to the incisive foramen. When associated with cleft lip, the defect can involve the midline of the soft palate and extend into the hard palate on one or both sides, exposing one or both of the nasal cavities as a unilateral or bilateral cleft palate. The palate can also have a submucosal cleft indicated by a bifid uvula, partial separation of muscle with intact mucosa, or a palpable notch at the posterior of the palate

200

A neonate with micrognathia and a high arched palate has signs of respiratory distress. The initial management response should be: A. Place the neonate in prone position B. Place the neonate in supine position C. Suction the nares D. Apply oxygen mask E. Call the plastic surgeon on call

What is Place the neonate in prone position Pierre Robin syndrome consists of micrognathia usually accompanied by a high arched or cleft palate. The tongue is usually of normal size, but the floor of the mouth is foreshortened. The air passages can become obstructed, particularly on inspiration, usually requiring treatment to prevent suffocation. The infant should be maintained in a prone or partially prone position so that the tongue falls forward to relieve respiratory obstruction. Some patients require tracheostomy. Mandibular distraction procedures in the neonate can improve mandibular size, enhance respiration, and facilitate oral feedings

300

Which statement regarding esophageal anomalies is NOT true? A. Esophageal atresia (EA) is the most common congenital anomaly of the esophagus B. In the most common form of EA, the proximal esophagus ends in a blind pouch and a tracheoesophageal fistula (TEF) connects to the distal esophagus C. Infants with EA have a > 90% survival D. More than 90% of infants with EA have other congenital anomalies E. A more distal TEF causes more severe pneumonitis than a more proximal one

What is More than 90% of infants with EA have other congenital anomalies Esophageal atresia (EA) is the most common congenital anomaly of the esophagus, affecting 1/4,000 neonates. Of these, > 90% have an associated tracheoesophageal fistula (TEF). In the most common form of EA, the upper esophagus ends in a blind pouch and the TEF is connected to the distal esophagus. The types of EA and TEF and their relative frequencies are shown in Figure 311-1. This defect has survival rates of > 90%, owing largely to improved neonatal intensive care, earlier recognition, and appropriate intervention. Infants weighing < 1,500 g at birth have the highest risk for mortality. Fifty percent of infants are nonsyndromic without other anomalies, and the rest have associated anomalies, most often associated with the VATER or VACTERL (vertebral, anorectal, [cardiac], tracheal, esophageal, renal, radial, [limb]) syndrome. The neonate with EA typically has frothing and bubbling at the mouth and nose after birth as well as episodes of coughing, cyanosis, and respiratory distress. Feeding exacerbates these symptoms, causes regurgitation, and can precipitate aspiration. Aspiration of gastric contents via a distal fistula causes more damaging pneumonitis than aspiration of pharyngeal secretions from the blind upper pouch. The infant with an isolated TEF in the absence of EA ("H-type" fistula) might come to medical attention later in life with chronic respiratory problems, including refractory bronchospasm and recurrent pneumonias.

400

A full-term infant with a history of polyhydramnios in utero has respiratory distress soon after birth. Which of the following diagnostic maneuvers should be performed? A. Chest radiography B. Lateral neck radiography C. Four-extremity blood pressures D. Passing a nasogastric tube, with subsequent chest radiography E. Transillumination of the chest

What is Passing a nasogastric tube, with subsequent chest radiography In the setting of early-onset respiratory distress, the inability to pass a nasogastric or orogastric tube in the newborn suggests esophageal atresia. Maternal polyhydramnios might alert the physician to EA. Plain radiography in the evaluation of respiratory distress might reveal a coiled feeding tube in the esophageal pouch and/or an air-distended stomach, indicating the presence of a coexisting TEF. Conversely, pure EA can manifest as an airless scaphoid abdomen. In isolated TEF (H type), an esophagogram with contrast medium injected under pressure can demonstrate the defect. Alternatively, the orifice may be detected at bronchoscopy or when methylene blue dye injected into the endotracheal tube during endoscopy is observed in the esophagus during forced inspiration.

500

A 15 yr old boy with a 12-yr history of microscopic hematuria is noted to have bilateral high-frequency sensorineural hearing loss, blood pressure of 140/90 mm Hg, serum creatinine of 1.5 mg/dL, and urinary protein of 2,000 mg/24 hr. This patient's mother also has microscopic hematuria. The most likely mode of inheritance for this child's glomerular disease is: A. Autosomal dominant with incomplete penetrance B. X-linked dominant C. Autosomal recessive D. X-linked recessive E. Autosomal dominant

What is X-linked dominant Alport syndrome (AS), hereditary nephritis, is a genetically heterogeneous disease caused by mutations in the genes coding for type IV collagen, a major component of basement membranes. Approximately 85% of patients have X-linked disease caused by a mutation in the COL4A5 gene encoding the α5 chain of type IV collagen. Bilateral sensorineural hearing loss, which is never congenital, occurs in 90% of hemizygous males with X-linked AS, 10% of heterozygous females with X-linked AS, and 67% of patients with autosomal recessive AS. This deficit begins in the high-frequency range but progresses to involve conversational speech, prompting the need for hearing aids.

CARDIAC

100

A 2 mo old infant has difficulty with feeding. She tires quickly and sweats with feeds. Hepatomegaly is appreciated on examination, and there is a harsh systolic murmur. Pulse oximetry is 97%. Initial evaluation should include: A. Chest radiograph and ECG B. Holter monitor C. Transthoracic echocardiogram D. Cardiac catheterization E. Cardiac MRI

What is Chest radiograph and ECG The initial evaluation for suspected congenital heart disease involves a systematic approach with three major components. First, congenital cardiac defects can be divided into 2 major groups based on the presence or absence of cyanosis, which can be determined by physical examination aided by pulse oximetry. Second, these 2 groups can be further subdivided according to whether the chest radiograph shows evidence of increased, normal, or decreased pulmonary vascular markings. Finally, the electrocardiogram can be used to determine whether right, left, or biventricular hypertrophy exists. The character of the heart sounds and the presence and character of any murmurs further narrow the differential diagnosis. The final diagnosis is then confirmed by echocardiography, CT or MRI, or cardiac catheterization.

200

A 6 mo old presents with tachycardia, tachypnea, and poor feeding for 3 mo. Physical examination reveals a continuous machinery murmur and a wide pulse pressure with a prominent apical impulse. The most likely diagnosis is: A. Pulmonic stenosis B. Aortic stenosis C. Ventricular septal defect D. Patent ductus arteriosus E. Anomalous coronary artery

What is Patent ductus arteriosus A large PDA will result in heart failure similar to that encountered in infants with a large VSD. A small PDA is associated with normal peripheral pulses, and a large PDA results in bounding peripheral arterial pulses and a wide pulse pressure, due to runoff of blood into the pulmonary artery during diastole. The heart is normal in size when the ductus is small, but moderately or grossly enlarged in cases with a large communication. In these cases, the apical impulse is prominent and, with cardiac enlargement, is heaving. A thrill, maximal in the 2nd left interspace, is often present and may radiate toward the left clavicle, down the left sternal border, or toward the apex. It is usually systolic but may also be palpated throughout the cardiac cycle. The classic continuous murmur is described as being like machinery in quality.

300

A 1 day old infant is noted to be cyanotic. Physical examination reveals a grade 2-3/6 systolic murmur and a single loud 2nd heart sound. The chest radiograph reveals a normal-sized heart and decreased pulmonary vascular markings. The ECG reveals left ventricular dominance. The next step in the management of this neonate is to administer: A. Sodium bicarbonate B. Morphine C. Prostaglandin E1 D. Digoxin E. Positive-pressure ventilation

What is Prostaglandin E1 If echocardiography is not immediately available, the clinician caring for a newborn with possible cyanotic heart disease should not hesitate to start a prostaglandin infusion (for a possible ductal-dependent lesion). Because of the risk of hypoventilation associated with prostaglandins, a practitioner skilled in neonatal endotracheal intubation must be available

400

Therapy of a "blue" or "tet" spell could include all of the following EXCEPT: A. Epinephrine B. Knee-chest position C. Oxygen D. Morphine E. Sodium bicarbonate F. Phenylephrine

What is Epinephrine Depending on the frequency and severity of hypercyanotic attacks, one or more of the following procedures should be instituted in sequence: (1) placement of the infant on the abdomen in the knee-chest position while making certain that the infant's clothing is not constrictive, (2) administration of oxygen (although increasing inspired oxygen will not reverse cyanosis caused by intracardiac shunting), and (3) injection of morphine subcutaneously in a dose not in excess of 0.2 mg/kg. Calming and holding the infant in a knee-chest position may abort progression of an early spell. Premature attempts to obtain blood samples may cause further agitation and be counterproductive. Because metabolic acidosis develops when arterial PO2 is < 40 mm Hg, rapid correction (within several minutes) with intravenous administration of sodium bicarbonate is necessary if the spell is unusually severe and the child shows a lack of response to the foregoing therapy. Recovery from the spell is usually rapid once the pH has returned to normal. Repeated blood pH measurements may be necessary because rapid recurrence of acidosis may ensue. For spells that are resistant to this therapy, intubation and sedation are often sufficient to break the spell. Drugs that increase systemic vascular resistance, such as intravenous phenylephrine, can improve right ventricular outflow, decrease the right-to-left shunt, and improve the symptoms. β-Adrenergic blockade by the intravenous administration of propranolol (0.1 mg/kg given slowly to a maximum of 0.2 mg/kg) has also been used.

500

Major findings in the Duke criteria for the diagnosis of endocarditis include all of the following EXCEPT: A. Two separate positive blood cultures for common bacteria B. Intracardiac mass on a valve seen with echocardiography C. Dehiscence of a prostatic valve D. Osler nodes E. More than two positive blood cultures for unusual bacteria

What is Osler nodes The Duke criteria help in the diagnosis of endocarditis. Major criteria include (1) positive blood cultures (2 separate cultures for a usual pathogen, 2 or more for less typical pathogens) and (2) evidence of endocarditis on echocardiography (intracardiac mass on a valve or other site, regurgitant flow near a prosthesis, abscess, partial dehiscence of prosthetic valves, or new valve regurgitant flow). Minor criteria include predisposing conditions, fever, embolic-vascular signs, immune complex phenomena (glomerulonephritis, arthritis, rheumatoid factor, Osler nodes, Roth spots), a single positive blood culture or serologic evidence of infection, and echocardiographic signs not meeting the major criteria. Two major criteria, 1 major and 3 minor, or 5 minor criteria suggest definite endocarditis. A modification of the Duke criteria may increase sensitivity while maintaining specificity. The following minor criteria are added to those already listed: the presence of newly diagnosed clubbing, splenomegaly, splinter hemorrhages, and petechiae; a high erythrocyte sedimentation rate; a high C-reactive protein level; and the presence of central nonfeeding lines, peripheral lines, and microscopic hematuria.

BLOOD

100

Splenic hypofunction is a usual finding in all of the following EXCEPT: A. Premature infants B. Sickle cell disease C. Congenital polysplenia D. Severe hemolytic anemia E. Metabolic storage diseases with splenomegaly

What is Congenital polysplenia Splenic function is usually normal in children with congenital polysplenia. Functional hyposplenism may occur in normal neonates, especially premature infants. Children with sickle cell hemoglobinopathies may have splenic hypofunction as early as 6 mo of age. Initially, this is caused by vascular obstruction, which can be reversed with red blood cell (RBC) transfusion or hydroxyurea. The spleen eventually autoinfarcts and becomes fibrotic and permanently nonfunctioning. Functional hyposplenism may also occur in malaria, after irradiation to the left upper quadrant, and when the reticuloendothelial function of the spleen is overwhelmed (as in severe hemolytic anemia or metabolic storage disease). Splenic hypofunction has been reported occasionally in patients with vasculitis, nephritis, inflammatory bowel disease, celiac disease, Pearson syndrome, Fanconi anemia, and graft-versus-host disease.

200

All of the following may cause autoimmune hemolytic anemia EXCEPT: A. Epstein-Barr virus B. Systemic lupus erythematosus C. Agammaglobulinemia D. Methyldopa E. Rhinovirus

What is Rhinovirus A number of extrinsic agents and disorders may lead to premature destruction of red blood cells (RBCs) (Table 458-1). Among the most clearly defined are antibodies associated with immune hemolytic anemias. The hallmark of this group of diseases is the positive result of the direct antiglobulin (Coombs) test, which detects a coating of immunoglobulin or components of complement on the RBC surface. The most important immune hemolytic disorder in pediatric practice is hemolytic disease of the newborn (erythroblastosis fetalis), caused by transplacental transfer of maternal antibody active against the RBCs of the fetus, that is, isoimmune hemolytic anemia (see Chapter 97.2). Various other immune hemolytic anemias are autoimmune (see Table 458-1) and may be idiopathic or related to various infections (Epstein-Barr virus, rarely HIV, cytomegalovirus, and Mycoplasma), immunologic diseases (systemic lupus erythematosus [SLE], rheumatoid arthritis), immunodeficiency diseases (agammaglobulinemia, autoimmune lymphoproliferative disorder, dysgammaglobulinemias), neoplasms (lymphoma, leukemia, and Hodgkin disease), or drugs (methyldopa, L-dopa). Other drugs (penicillins, cephalosporins) cause hemolysis by means of "drug-dependent" antibodies, that is, antibodies directed toward the drug and in some cases toward an RBC membrane antigen as well.

300

All of the following statements regarding G6PD deficiency are true EXCEPT: A. Symptoms usually develop in patients with G6PD deficiency 24-48 hr after ingesting a substance with oxidative properties B. Infection may result in hemolysis in patients with G6PD deficiency C. A pregnant woman who ingests oxidative drugs may cause hemolytic anemia in a fetus with G6PD deficiency D. Enzyme activity in affected persons is 10% of normal or less E. The usual dose of aspirin causes clinically relevant hemolysis in the A variety of G6PD deficiency

What is The usual dose of aspirin causes clinically relevant hemolysis in the A variety of G6PD deficiency The usual doses of aspirin and trimethoprim-sulfamethoxazole do not cause clinically relevant hemolysis in the A variety. Aspirin administered in doses used for acute rheumatic fever (60-100 mg/kg/24 hr) may produce a severe hemolytic episode.

400

All of the following statements are true EXCEPT: A. In most instances of warm antibody hemolysis, no underlying cause is found B. Most children with autoimmune hemolytic anemia have a chronic, unremitting course C. The hallmark of the autoimmune hemolytic anemias is a positive result on the direct Coombs test D. Cold antibodies are primarily of the IgM class and require complement for activity E. Paroxysmal cold hemoglobinuria may account for 30% of immune hemolytic episodes among children

What is Most children with autoimmune hemolytic anemia have a chronic, unremitting course Autoimmune hemolytic anemias may occur in either of 2 general clinical patterns. The 1st, an acute transient type lasting 3-6 mo and occurring predominantly in children ages 2-12 yr, accounts for 70-80% of patients. It is frequently preceded by an infection, usually respiratory. Onset may be acute, with prostration, pallor, jaundice, fever, and hemoglobinuria, or more gradual, with primarily fatigue and pallor. The spleen is usually enlarged and is the primary site of destruction of immunoglobulin G (IgG)–coated RBCs. Underlying systemic disorders are unusual. A consistent response to glucocorticoid therapy, a low mortality rate, and full recovery are characteristic of the acute form. The other clinical pattern involves a prolonged and chronic course, which is more frequent in infants and in children > 12 yr old. Hemolysis may continue for many months or years. Abnormalities involving other blood elements are common, and the response to glucocorticoids is variable and inconsistent. The mortality rate is approximately 10%, and death is often attributable to an underlying systemic disease.

500

All of the following statements concerning acute lymphocytic leukemia (ALL) are true EXCEPT: A. Most cases (about 85%) are derived from T-cell progenitors B. Staging of ALL is based on bone marrow biopsy and cerebrospinal fluid examination C. Chromosomal abnormalities are identified in most cases of ALL D. Exposure to medical radiation is associated with an increased incidence of ALL E. Childhood ALL was the 1st form of cancer shown to be curable with chemotherapy and irradiation

What is Most cases (about 85%) are derived from T-cell progenitors Precursor B-cell ALL (CD10+ or common acute lymphoblastic leukemia antigen [CALLA] positive) is the most common immunophenotype (see Table 489-2), with onset at 1-10 yr of age.