A 16-day-old infant presents with fever, irritability, poor feeding, and a bulging fontanelle. Spinal fluid demonstrates gram-positive cocci. Which of the following is the most likely diagnosis?
a. Listeria monocytogenes
b. Group A streptococcus
c. Group B streptococcus
d. Streptococcus pneumoniae
e. Staphylococcus aureus
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; Group B streptococcus.
Many organisms can cause meningitis in the neonate, including Escherichia coli, Listeria monocytogenes, Haemophilus influenzae, gram-negative rods, group B streptococci, and coagulase-positive and coagulase-negative staphylococci; statistically, the most likely cause in this case is late-onset group B streptococcus. Clinical manifestations of meningitis in neonates include lethargy, bulging fontanelle, seizures, and nuchal rigidity. The diagnosis is made with examination and culture of the cerebrospinal fluid. Treatment is begun while awaiting the results of the spinal fluid analysis. Appropriate antibiotic coverage must include activity against gram-positive and gram-negative organisms (ampicillin and gentamicin or cefotaxime).