A 10-year-old boy from the Connecticut coast is seen because of discomfort in his right knee. He had a large, annular, erythematous lesion on his back that disappeared 4 weeks prior to the present visit. His mother recalls pulling a small tick off his back. Which of the following is a correct statement about this child’s likely illness?
a. The tick was probably a Dermacentor andersoni
b. The disease is caused by a rickettsial agent that is transmitted by the bite of a tick
c. In addition to skin and joint involvement, CNS and cardiac abnormalities may be present
d. Therapy with antibiotics has little effect on the resolution of symptoms
e. The pathognomonic skin lesion is required for diagnosis
the answer is below…
The United States Medical Licensing Examination, or USMLE for short, is a three-part licensing examination that is required in order to receive a license to practice medicine within the United States.
The USMLE assesses a physician’s ability to apply knowledge, concepts, and principles, and to determine fundamental patient-centered skills that are important in health and disease and that constitute the basis of safe and effective patient care.Examination committees composed of medical educators and clinicians from across the United States and its territories prepare the examination materials each year.
This exam is designed by the Federation of State Medical Boards and the National Board of Medical Examiners to determine whether or not an individual understands and can apply the knowledge necessary to practice medicine safely and intelligently.
The USMLE is actually comprised of three different exams that are referred to as steps, which examine the individual’s knowledge of specific topics related to the field of medicine such as basic science, medical knowledge, medical skills, clinical science, and the application of all of these skills and areas of knowledge in the medical field.
All three steps of the USMLE include a series of computerized multiple-choice questions, but the format of the exam and the information covered in each multiple-choice section is different for each step of the USMLE. The USMLE Step II also has a clinical skills portion that examines an individual’s ability to work with real patients and the USMLE Step III has a computerized patient simulation portion in addition to the multiple-choice section of the exam. In order for an individual to receive a license to practice medicine, the individual must pass all three steps of the USMLE.
The correct answer is c; In addition to skin and joint involvement, CNS and cardiac abnormalities may be present.
Lyme disease, caused by the spirochete Borrelia burgdorferi and transmitted mostly by ticks of the ioxodes family, is characterized by a unique skin lesion, recurrent attacks of arthritis, and occasional involvement of the heart and central nervous system (CNS). Illness usually appears in late summer or early fall, 2 to 30 days after a bite by an infecting tick. Erythema chronicum migrans begins as a red macule, usually on the trunk at the site of tick attachment, that enlarges in a circular fashion with central clearing. Nonspecific systemic signs include headache, fever, and malaise. Joint involvement generally occurs days to years after onset of the rash. Cardiac disease consists primarily of disturbances of rhythm. Involvement of the CNS is evidenced by headache and stiff neck. The diagnosis should be suspected when any of the signs and symptoms occur, because the disease can present in an atypical manner. The characteristic lesion of erythema chronicum migrans, as well as the history of tick bite, have frequently not been noted by the patient. It is not until late joint, heart, or neurologic manifestations occur, and Lyme disease is suspected, that serologic evidence confirms the etiology. Serologic evidence is sought when the patient has spent time in summer months in endemic areas or there is a risk of tick bite. Treatment with penicillin or tetracycline results in a faster resolution of symptoms and prevention of later complications, especially if given early in the course of the disease.