A 1-day-old infant who received silver nitrate eye drops in the delivery room is suffering from bilateral purulent conjunctival discharge. Which of the following is the most likely cause of this child's condition?
Answer(s): D
Silver nitrate, the traditional prophylactic treatment for the neonate's eyes, is very effective against gonorrheal ophthalmitis. These drops are not effective against the most common cause of neonatal conjunctivitis, C. trachomatis, which requires erythromycin or tetracycline for eradication. Silver nitrate is commonly associated with the sterile purulent discharge of chemical conjunctivitis. HSV can cause neonatal conjunctivitis, but its occurrence on the first day of life would be unusual. Pseudomonas conjunctivitis generally is hospital acquired, occurring in ill infants receiving mechanical ventilation.Nasolacrimal duct obstruction is a transient structural anomaly that may be accompanied by persistent tearing and occasional purulent discharge. The condition is usually unilateral and clears within 69 months after birth. Rarely, duct probing or surgery is necessary because of persistent stenosis beyond 1 year of age or for repeated infections.
A 2-year-old girl presents with fever of 39.3°C and irritability. She has had an upper respiratory tract infection for 4 days. On examination, the right ear is bulging and has poor movement on insufflation. Which of the following organisms is most likely responsible for these findings?
Answer(s): A
Nontypeable H. influenzae, S. pneumoniae, and M. catarrhalis are the most common bacterial pathogens in otitis media of children. S. aureus, E. coli, and group A Streptococci each account for 2% or less of all cases of otitis media in children beyond the neonatal period. Mycoplasma is thought to be an uncommon cause of otitis media
Afew weeks after a presumed viral respiratory infection, a 4-year-old girl presents with bruising and petechiae. Bone marrow examination reveals increased numbers of megakaryocytes but is otherwise normal. Hb is 13.5 g/100 mL. Platelet count is 30,000/mm3. Which of the following would be appropriate for this child at this time?
Answer(s): E
Most cases of idiopathic thrombocytopenic purpura (ITP) in children are preceded by viral infections and, in contrast to adults, the great majority of children recover spontaneously. Although not all patients require therapy, most authorities suggest treating when the platelet count is less than 20,000. Standard treatment has been oral prednisone. Recently, IV gamma globulin has been shown to be effective. However, this agent is expensive and less convenient than oral prednisone. The child described in the question might reasonably be treated with either agent. Because the child's Hb is 13.3 g/100 mL, there is no indication for transfusion of RBCs. Although the platelet count is very low, platelet transfusions are short lived and generally are indicated only in the presence of serious bleeding, as, for example, from the GI tract. Thus, platelet transfusions are not indicated in this patient. Splenectomy is reserved for the very rare child who does not respond to conservative therapy or who develops chronic ITP.
A4-month-old child presents with a 2-day history of vomiting and intermittent irritability. On examination, "currant jelly" stool is noted in the diaper, and a sausage-shaped mass is palpated in the right upper quadrant of the abdomen. Which of the following conditions is most likely to cause this?
Intussusception, or telescoping of the bowel into a more distal section of bowel, is the most common cause of intestinal obstruction in infants aged 312 months. The case presented represents the classic presentation. Giardiasis presents less acutely and would not be associated with a mass. In gastroenteritis, frequent loose stools without blood would be the major symptom. Diaphragmatic hernia occurs in newborns, and the major symptom is respiratory distress. Although appendicitis can occur in infants, it is very unusual.
During a routine yearly checkup, a 10-year-old boy is found to have 2 + proteinuria on urinalysis. Which of the following would be the most appropriate diagnostic test?
Many healthy children have intermittent proteinuria. Transient proteinuria may occur with fever, strenuous exercise, and cold exposure. Testing for hematuria and RBCs and casts should be done. BP should also be checked. When proteinuria is intermittent and not accompanied by hematuria, chronic renal disease is unusual. Achild who has proteinuria on a single specimen, thus, will need repeated urinalyses. If isolated proteinuria is present in three consecutive urinalyses testing for orthostatic proteinuria should be considered. If this test is negative, qualitative measurement of proteinuria can confirm the diagnosis (>4 mg/m2/h) and further evaluation may be considered. If proteinuria remains intermittent, most physicians do not perform invasive procedures such as a biopsy. Proteinuria alone is unlikely to be an indicator of UTI or structural kidney disease; thus, an IVP and renal ultrasound are unlikely to be helpful. Likewise, with isolated and intermittent proteinuria as the only abnormality, electrolytes, BUN, and creatinine levels are highly unlikely to be abnormal.
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