A 4-year-old child presents with an enlarged submandibular node that is 4 cm in diameter, nontender, and not fluctuant. The node has been enlarged for about 4 weeks, and there is no history of fever or contact with any person who was ill. A CBC is normal, and a Mantoux test with 5 tuberculin units of PPD shows 6 mm of induration. Which of the following is the most likely diagnosis?
Answer(s): E
Nontuberculous lymphadenitis (atypical mycobacteria) is characterized by nontender lymphadenitis.Affected persons are usually afebrile, and the CBC is usually normal. Unlike tuberculous lymphadenitis, a history of contact with a tuberculous individual is lacking, and the reaction to 5 tuberculin units of PPD is almost always less than 10 mm of induration. Cat-scratch fever is characterized by tender, fluctuating nodes and low-grade fever. Acute lymphadenitis is characterized by tender nodes that may fluctuate. The WBC count is often elevated, and there is frequently a shift to the left on the differential. In addition, the sufferer is often febrile. Acute lymphoblastic leukemia may present as lymphadenitis, but the CBC is usually abnormal, with blasts present on the peripheral smear
A4-year-old child with grade III vesicoureteral reflux has recurrent UTIs despite adequate antibiotic prophylaxis. Which of the following is the most appropriate next step in the treatment of this patient?
Answer(s): D
Vesicoureteral reflux is the most common anatomic abnormality associated with recurrent UTI in children.Many cases of reflux are the result of an inadequate length of submucosal ureter immediately proximal to its opening into the bladder lumen, a condition that sometimes requires surgical correction. However, in other children, reflux often seems to result from the direct effects of infection on ureteral tone and peristalsis. Thus, many children may outgrow mild degrees of reflux if they are maintained on prophylactic antibiotics. Moderate-to-severe degrees of reflux frequently require surgery. Failure of adequate antibiotic treatment to prevent infection is also a prime indication for surgery. Repeating an IVP or performing a renal arteriogram on an already diagnosed case would not be useful, although a radionuclide scan may be very helpful to determine the present degree of reflux with a minimum of radiation exposure. Vitamin C, although reportedly useful in acidifying the urine to help prevent infection, does not enhance adequate antibiotic prophylaxis. IV antibiotics would be necessary only if oral antibiotics were not successful in eradicating infection.
A 2-week-old Caucasian male presents with constipation since birth. He was born full term via a normal vaginal delivery. He did not pass meconium till his 3rd day of life, after he was given a glycerin suppository. He has since stooled every 34 days, only with the help of a suppository. The stools are pellet like. He has had increasing abdominal distention. On rectal examination, tone appears normal and the ampulla contains no stool.Which of the following is the most likely cause?
Answer(s): B
Hirschprung disease or congenital aganglionic megacolon is the most common cause of lower intestinal obstruction in neonates. Incidence is 1/5000 live births; males are four times as likely to be affected. Initial presentation is with delayed passage of meconium. Failure to pass stools leads to dilation of proximal bowel and abdominal distention. Diagnosis is by barium enema which reveals a small-caliber rectum with transition in the rectosigmoid to a dilated, obstructed proximal colon. Diagnosis is confirmed by biopsy.Meconium plugs and meconium ileus are often found in cystic fibrosis, which should be excluded. Anal stenosis may be diagnosed by rectal examination or endoscopy. Functional constipation usually presents in children older than 2 years. There may be some abdominal distention; anal tone is usually normal, and the rectal ampulla is often full of stool. Congenital hypothyroidism may present with constipation; neonatal screening tests usually allow early diagnosis. Other features include feeding difficulties, prolonged jaundice, sluggishness, a large abdomen with umbilical hernia, subnormal body temperature, myxedema, and developmental delay.
Which of the following is the most appropriate evaluative procedure for an otherwise normal 7-day-old boy with perineal hypospadias?
Answer(s): A
Children with more severe cases of hypospadias have an increased incidence of concomitant urinary tract anomalies and require careful evaluation. Ultrasonography is a safe and noninvasive procedure that is sensitive in the diagnosis of neonatal urinary tract pathology. It is a better choice than either IVP or cystography which use contrast media and radiation. Serum creatinine determinations are a measure of renal function and are unnecessary in an otherwise healthy child. Circumcision is not indicated in children with hypospadias. In fact, it may be contraindicated in cases of second- or third-degree hypospadias, in which the prepuce can be used to construct an absent distal segment of urethra.
A 2-week-old infant presents with hepatosplenomegaly and a thick, purulent, bloody nasal discharge. Coppery, oval, maculopapular skin lesions are present in an acral distribution. The neurologic examination is normal, including head circumference. Which of the following is the most likely cause of this congenital infection?
Transplacental passage of T. pallidum causes widespread disease in the fetus. Organs most severely affected include brain, bone, liver, and lung. Hepatosplenomegaly, rare in neonates with GBS or HSV infections, occurs in 90% of neonates with congenital syphilis. Mucocutaneous lesions produce a persistent, purulent, often bloody nasal discharge which is termed snuffles. This nasal discharge is highly infectious. Skin rash is uncommon in CMV and GBS infections. The acral distribution described is characteristic of congenital syphilis. Congenital toxoplasmosis characteristically presents with neurologic abnormalities. The classic triad includes hydrocephalus, chorioretinitis, and diffuse intracranial calcifications
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