A beekeeper's previously healthy 6-month-old son develops gradual onset of lethargy, poor feeding, constipation, and generalized weakness. On taking a history, you determine that the child has recently been placed on a homemade formula consisting of evaporated milk, water, and honey. Which of the following is the most likely for this symptom complex?
Answer(s): E
The child described in the question seems to be afflicted with infant botulism. Clostridium botulinum spores are commonly found in honey, and the toxin responsible for the symptoms described is produced in the infant's GI tract. Therefore, children younger than 1 year should not be fed honey. Hypernatremic dehydration may show some similarities to infant botulism, but the skin and mucous membranes are characteristically dry. Serum sodium level is often greater than 160. Hirschsprung disease would explain constipation but not the other findings listed. Congenital hypothyroidism shows a more insidious onset, with prolonged constipation and weakness. In addition, developmental retardation would likely be present.
A 12-month-old patient has allergies to multiple foods. The child's mother has eliminated the foods from the diet and wants to know if these allergies will be lifelong. You tell her that some allergies do get better if the food is eliminated for 12 years. In which of the following is the allergy most likely to resolve, with elimination of the food from the diet?
Answer(s): B
Cow's milk allergy may occur in 23% of infants and toddlers. After elimination from the diet, by age 3, 85% no longer have symptoms on food challenge. Older children and adults may also lose sensitivity to an offending food when it is eliminated from the diet for 12 years. The exceptions are IgE-mediated allergies to peanuts, nuts, fish, or shellfish.
A 4-year-old child manifests symptoms of fever, sore throat, and swollen lymph nodes. The spleen tip is palpable. Throat culture and rapid slide (Monospot) test results are negative. The next logical diagnostic procedure would involve which of the following?
Answer(s): C
Infectious mononucleosis may affect children of all ages. The rapid slide (Monospot) test response is positive in approximately 90% of infected persons; however, younger children with mononucleosis may have a negative result. Moreover, many younger children have poor antibody response to the heterophil titer test. The specific serodiagnostic test for EBV, the agent responsible for most cases of infectious mononucleosis, confirms the diagnosis. A repeat throat culture, even if positive for betahemolytic Streptococcus, may be of only partial value, because both infectious mononucleosis and streptococcal pharyngitis may be present simultaneously. Bone marrow examinations potentially are painful and contribute little to the correct diagnosis.
A2-year-old child is brought to the emergency department with sudden onset of nresponsiveness, miosis, bradycardia, and muscle fasciculations. These findings are most suggestive of poisoning with which of the following?
Organophosphate poisoning is a leading cause of fatal ingestions of nonpharmaceutical compounds.Common components of insecticides, organophosphates are readily absorbed across skin and mucous membranes. They bind irreversibly to cholinesterase, which results in prolongation of the effects of acetylcholine, centrally and peripherally. Symptoms include muscle fasciculations, paralysis (nicotinic effect) and miosis, salivation, diarrhea, bradycardia, lacrimation (muscarinic effect) and obtundation, seizures, or apnea (central effect).Acetaminophen ingestion can present with vomiting and then later signs of liver failure if it is severe enough. Patients with salicylate overdose present with hypoglycemia, respiratory alkalosis followed by metabolic acidosis, hypokalemia, and mental status changes. Tricyclic antidepressants poisoning causes arrhythmias, mental status changes, and anticholinergic symptoms. Patients with acute vitamin Atoxicity have mental status changes, nausea, and vomiting.
A 2-year-old boy presents with refusal to use his right arm for 1 day. He is otherwise well.His mother states she pulled upward on his arm the previous evening to keep him from tripping down the stairs.Which of the following is the most likely diagnosis?
Nursemaid's elbow, or subluxation of the radial head, occurs in children following longitudinal traction on a pronated extended elbow. When attempting to restrain a child, an uninformed caretaker may jerk on a child's upper extremity. The result is a painful subluxed elbow that is easily reduced by simultaneous flexion and supination of the forearm.
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