A 32-year-old man from a rural area of southern Africa was recently brought to the United States by some of his family members who had emigrated previously. His family says that he was diagnosed with syphilis at age 16 and has taken penicillin off and on over the years, but never completed the prescribed course. Assuming that he has neurosyphilis, which of the following is true with regard to the classic pupillary defect most likely to be observed?
a. Completely normal (no defect)
b. Reacts poorly to light but accommodates well
c. Accommodates poorly but reacts well to light
d. Is pinpoint and regular in shape
e. Is fixed and dilated
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 b; Reacts poorly to light but accommodates well.
The patient with neurosyphilis may develop an Argyll Robertson pupil. The pupil is usually poorly reactive to light, small, and irregular in shape. Both eyes or only one eye may be affected. Although reactivity to light is deficient, pupillary accommodation with changes in distance from the eye is usually good. The pupillary reaction may, however, be complicated by optic atrophy, which also may develop as a consequence of neurosyphilis. Pinpoint pupils are seen in pontine disease due to interruption of the pupillodilator pathways in the brainstem. The fixed and dilated pupil is generally a sign of third-nerve injury due to compression of the nerve by a vascular or other mass. In the patient with diminished consciousness and contralateral hemiparesis, the concern is for herniation. Other, more benign causes of the fixed and dilated pupil include uveitis, Adie’s tonic pupil, and drug-induced iridoplegia (i.e., paralysis of the iris by intentional or accidental application of sympathomimetic or anticholinergic medications).