A 7-year-old boy presents with a rash. His mother states that he was well until 3 days ago when he developed fever and malaise. The next day, the rash started as papules on the trunk, which rapidly changed to vesicles. The lesions have spread all over the body. On physical examination, he has no fever and seems well. You note numerous vesicles all over the body, some of which have crusted over.Which of the following is the most likely diagnosis?
Answer(s): A
This is a typical presentation of chicken pox. A prodrome of fever and malaise is followed by the rapid eruption of papules that turn to vesicles and crust over. The rash in measles, rubella, and Kawasaki disease are macular or maculopapular. In staphylococcal scalded skin syndrome, a diffuse, tender erythroderma develops
An 18-month-old girl is brought to the hospital with a history of 6 days of bloody diarrhea. She has been drinking well but has not been wetting her diaper. She has been irritable. On physical examination, she has periorbital edema. She appears pale and is tachycardic. Her CBC shows a hemoglobin of 6 g/dL and a platelet count of 100,000/mm3. Her blood urea nitrogen (BUN) is 50 mg/dL and creatinine is 5.5 mg/dL. Her urinalysis shows gross hematuria. Which of the following is the most likely causative organism for her clinical problem?
The child most likely has hemolytic-uremic syndrome. This illness is most common in children under 2 years old. They present with a prodromal illness, bloody diarrhea, and then a sudden onset of lethargy and pallor when the hemolytic anemia occurs. Coincident with this is the development of acute renal failure, often with low urine output. E. coli 0157:H7 is the most common organism in the United States. Group A Streptococci are associated with poststreptococcal acute glomerulonephritis.Thrombocytopenia and anemia are not seen in this disease.
A1-year-old child with ALL in remission for 3 months is in the office for a health maintenance visit. He is due for multiple vaccinations including hepatitis B vaccine, inactivated polio vaccine (IPV), varicella vaccine A. influenzae B vaccine (Hib), and pneumococcal vaccine (PCV). You remember that some of these vaccines are live attenuated viruses and are contraindicated in immunocompromised patients.Which vaccine will you not give to this patient?
Answer(s): B
Varicella vaccine is a live vaccine. All others are killed vaccines. Diphtheria and tetanus are both toxoids, the others are from killed microorganisms.
A9-year-old boy presents with a several-day history of progressive arm and leg weakness. He has been well except for an upper respiratory infection 2 weeks ago. The patient is alert and oriented. On repeated examination, the heart rate varies between 60 and 140 beats/min, and the blood pressure (BP) varies between 90/60 and 140/90 mmHg. Respirations are shallow, with a rate of 50/min. There is symmetric weakness of the face and all four extremities. Deep tendon reflexes are absent. Sensation is intact.Which of the following is the most likely diagnosis?
Answer(s): D
Progressive, symmetric motor weakness, areflexia, and autonomic instability, with mild or absent sensory signs, are typical features of Guillain-Barré syndrome. Frequently, there is a history of infection (often respiratory) in the several weeks preceding clinical onset of the syndrome. Supportive evidence for the diagnosis includes elevation of CSF protein concentration with a mild (10 or fewer cells/mL) mononuclear pleocytosis, and slowing of nerve conduction velocities. In polymyositis, deep tendon reflexes would be intact. Myasthenia gravis is characterized by weakness aggravated by repetitive movement. In transverse myelitis, sensation would also be lost. Viral encephalitis is characterized by mental status abnormalities.
An infant is due for her first dose of polio vaccine.Her parents have heard that there are two different types of vaccine for polio. They want to know why their daughter needs to get another shot rather than just taking the oral form of the vaccine. You tell the parents the major advantage of the injectable vaccine is which of the following?
In 1997, the expanded use of IPV in the United States began. Before this, the risk of vaccine-associated paralytic polio was 1 case per 2.4 million doses of oral polio vaccine (OPV); the rate after the first dose was 1 per 750,000 doses, including vaccine recipient and contact cases. This is the main disadvantage of the OPV vaccine. Although it is contraindicated in children or their contacts with immunodeficiencies, they are at high risk in case of inadvertent exposure, because there is feco-oral transmission of the virus for 46 weeks after the vaccine is given. The advantages of the OPV include lower cost, fewer "shots," and boosting herd immunity. The OPV vaccine is still recommended for global polio eradication.
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