A patient presents with a history of recurrent nosebleeds, easy bruising, and gum bleeding. Laboratory tests reveal prolonged bleeding time and normal platelet count, PT, and aPTT. Which of the following conditions is most likely to cause these findings?

Correct Answer: A

Rationale: Von Willebrand disease is a hereditary bleeding disorder that results from a deficiency or dysfunction of von Willebrand factor (vWF), a protein that plays a key role in platelet adhesion and the initiation of primary hemostasis. The clinical manifestations of von Willebrand disease include recurrent mucocutaneous bleeding, such as nosebleeds, easy bruising, and gum bleeding. Laboratory findings typically show a prolonged bleeding time due to impaired platelet function, while platelet count, PT (prothrombin time), and aPTT (activated partial thromboplastin time) are usually normal. This distinguishes von Willebrand disease from other bleeding disorders such as hemophilia A (Factor VIII deficiency), which would show abnormal PT and aPTT due to deficiencies in specific clotting factors. Thrombocytopenia, on the other hand, would be characterized by a low platelet count

Correct Answer: A

Rationale: The combination of recurrent joint pain, swelling, and limited range of motion in multiple joints along with elevated ESR, positive RF, and presence of anti-CCP antibodies is classic for rheumatoid arthritis (RA). Elevated ESR indicates inflammation, positive rheumatoid factor (RF) is an autoantibody commonly found in the serum of patients with RA, and the presence of anti-cyclic citrullinated peptide (anti-CCP) antibodies further supports the diagnosis of RA. These laboratory findings along with the clinical presentation are highly suggestive of rheumatoid arthritis. Systemic lupus erythematosus (SLE), ankylosing spondylitis (AS), and psoriatic arthritis (PsA) can have overlapping symptoms with RA, but the specific combination of elevated ESR, positive RF, and anti-CCP antibodies points more towards RA in this scenario.

Correct Answer: B

Rationale: Vestibular neuritis is a condition characterized by the acute onset of severe vertigo, nausea, vomiting, and nystagmus. These symptoms are typically worsened by head movement. Vestibular neuritis is caused by inflammation of the vestibular nerve, which plays a key role in balance and spatial orientation. The classic presentation of these symptoms, along with the absence of hearing loss (which is seen in labyrinthitis), points towards vestibular neuritis as the most likely cause in this scenario. Meniere's disease presents with recurrent episodes of vertigo, hearing loss, tinnitus, and sensation of fullness in the ear. Benign paroxysmal positional vertigo (BPPV) is characterized by brief episodes of vertigo triggered by changes in head position.

Correct Answer: C

Rationale: The symptoms described, including progressive weakness, muscle atrophy, fasciculations, dysphagia, and dysarthria primarily involving the upper and lower extremities, are classic features of amyotrophic lateral sclerosis (ALS), also known as Lou Gehrig's disease. ALS is a progressive neurodegenerative disorder that affects the motor neurons in the brain and spinal cord, leading to muscle weakness and atrophy. As the disease progresses, patients may develop difficulty swallowing (dysphagia) and speaking (dysarthria). In contrast, Parkinson's disease primarily involves movement-related symptoms such as tremors, muscle stiffness, and slow movements. Guillain-Barré syndrome (GBS) is an acute inflammatory demyelinating polyneuropathy that typically presents with ascending weakness and sensory abnormalities, often preceded by an infection. Myasthenia gravis is characterized by muscle weakness exacerbated by

Correct Answer: A

Rationale: The patient's presentation of episodic throbbing headache associated with nausea, vomiting, sensitivity to light and sound, and aura suggests a diagnosis of migraine headache. Migraines are a common neurological condition characterized by recurrent moderate to severe headaches that are often unilateral, pulsating, and aggravated by physical activity. The presence of premonitory symptoms (aura) before the headache is a key feature commonly seen in migraines. Additionally, nausea, vomiting, and sensitivity to light and sound are also common features associated with migraines.