USMLE (United States Medical Licensing Examination) Step 1 Practice Exam

Which syndrome presents with paraneoplastic features like myoclonic jerks and chaotic eye movements?

1. Addison disease

2. Neuroblastoma

3. Hypoparathyroidism

4. Resp Alkylosis + Ca2+ Homeostasis

The correct answer is: Neuroblastoma

Neuroblastoma is correctly identified as the syndrome that can present with paraneoplastic features such as myoclonic jerks and chaotic eye movements. This condition is a type of cancer that most commonly arises in and around the adrenal glands, but can also develop in the nerve tissue along the spine, in the abdomen, or in the chest or neck. Neuroblastoma is known for its ability to produce a variety of paraneoplastic syndromes due to the release of neurotransmitters and other substances from the tumor cells. These paraneoplastic features can include neurological symptoms like myoclonic jerks (involuntary muscle twitches) and abnormal eye movements, reflecting the impact on the central nervous system. Other options, while significant in their own rights, do not typically associate with these specific neurological paraneoplastic manifestations. For example, Addison disease is an adrenal insufficiency that primarily leads to hormonal deficits rather than neurological symptoms. Hypoparathyroidism involves low parathyroid hormone levels affecting calcium levels, but does not result in paraneoplastic neurological symptoms. Similarly, respiratory alkalosis and disturbances in calcium homeostasis do not directly relate to the paraneoplastic features seen in Neuroblastoma. Thus, Neuroblastoma is the syndrome