A 65-year-old man with known Parkinson’s disease presents with increasing “on-off” fluctuations despite being on levodopa/carbidopa therapy for 5 years. He reports periods where he experiences normal motor function (“on” periods), alternating with sudden episodes of stiffness and freezing (“off” periods). His symptoms are most pronounced before the next scheduled dose of levodopa. Question: Which of the following is the most appropriate next step in managing his motor fluctuations?

A 68-year-old man presents to the clinic with complaints of progressive stiffness, a resting tremor in his right hand, and difficulty initiating movement. His wife reports that he has become less expressive and has developed a “shuffling gait.” On examination, the patient shows bradykinesia, cogwheel rigidity, and a positive pull test. A trial of levodopa significantly improves his symptoms. Question: Which of the following is the most characteristic symptom of Parkinson’s disease that must be present to make the clinical diagnosis?

A 62-year-old woman presents to the clinic with a 2-year history of progressive slowness in movement, difficulty getting out of chairs, and a resting tremor in her right hand. She also reports a “dragging” sensation in her right foot and increasing fatigue with activity. On examination, she has a resting tremor in her right hand, cogwheel rigidity in her arms, and delayed initiation of movement. There is no weakness or sensory loss. Question: Which of the following is the most likely pathological finding in this patient’s condition?

A 63-year-old retired librarian comes to your clinic with complaints of a noticeable tremor in her right hand, which is more pronounced when she’s not actively using it, like during rest periods. She also mentions difficulty in initiating movement, especially when rising from a chair or turning around in bed, describing a feeling of being “stuck” before she can move. She has no history of similar symptoms in her family. Which of the following brain structures is most likely to be affected in this patient?

A 67-year-old man presents to the clinic with progressive difficulty in movement over the past two years. He reports slowness in initiating movements, difficulty rising from chairs, and a noticeable tremor in his right hand that worsens at rest but improves when he is active. His wife mentions that he has developed a mask-like facial expression and soft speech. The patient also complains of small, cramped handwriting and frequent constipation. On physical examination, you note: Bradykinesia: Delayed initiation and slowed execution of voluntary movements. Resting tremor: A “pill-rolling” tremor in the right hand. Cogwheel rigidity: Resistance to passive movement of the arms. Postural instability: Mild unsteadiness during the pull test. No signs of weakness, sensory deficits, or cerebellar dysfunction are observed. Laboratory and Imaging Workup: MRI of the brain is normal, ruling out structural causes. A positive response to a trial of levodopa. Question: What is the most likely diagnosis?

Adam, a 4-year-old male, is brought to the pediatric clinic by his parents due to concerns about delayed motor milestones and difficulty getting up from the floor. His parents report that Adam started walking at 18 months and continues to lag behind peers in activities like climbing stairs and running. Over the past year, they have also noticed that Adam uses his hands to push off his thighs when standing up, a behavior his parents find unusual. Adam’s parents report that he has no history of trauma or illness to explain his motor difficulties. He has frequent falls when walking and struggles to keep up with other children during play. They have also noticed that his calves appear unusually large, which they initially attributed to his growth. He has no complaints of pain, but he often seems fatigued after physical activity. Adam was born full-term with no complications during pregnancy or delivery. He has no significant medical history. There is no family history of neuromuscular disorders, but Adam’s maternal uncle reportedly had mobility challenges as a teenager. Physical Examination: General Appearance: Alert and cooperative. Musculoskeletal: Difficulty rising from a seated position; using hands to push off thighs to stand Neurological: Proximal muscle weakness in the hips and thighs. Reflexes are intact, and there are no sensory deficits. Diagnostic Workup: 1.Laboratory Tests: Creatine Kinase (CK): 15,000 U/L 2.Electromyography (EMG): Demonstrates myopathic changes. Which of the following tests is most commonly used to confirm the diagnosis of this disorder( Duchenne muscular dystrophy)?

Adam, a 4-year-old male, is brought to the pediatric clinic by his parents due to concerns about delayed motor milestones and difficulty getting up from the floor. His parents report that Adam started walking at 18 months and continues to lag behind peers in activities like climbing stairs and running. Over the past year, they have also noticed that Adam uses his hands to push off his thighs when standing up, a behavior his parents find unusual. Adam’s parents report that he has no history of trauma or illness to explain his motor difficulties. He has frequent falls when walking and struggles to keep up with other children during play. He has no complaints of pain, but he often seems fatigued after physical activity. Adam was born full-term with no complications during pregnancy or delivery. He has no significant medical history. There is no family history of neuromuscular disorders, but his maternal uncle reportedly had mobility challenges as a teenager. Physical Examination: General Appearance: Alert and cooperative. Musculoskeletal: Difficulty rising from a seated position; using hands to push off thighs to stand Neurological: Proximal muscle weakness in the hips and thighs. Reflexes are intact, and there are no sensory deficits. Diagnostic Workup: 1.Laboratory Tests: Creatine Kinase (CK): 15,000 U/L 2.Electromyography (EMG): Demonstrates myopathic changes. 2.Genetic Testing: Confirms a deletion in the gene on X chromosome What is a hallmark clinical sign of this disorder ( Duchenne muscular dystrophy) in young children?

Patient Case: Duchenne Muscular Dystrophy Adam, a 4-year-old male, is brought to the pediatric clinic by his parents due to concerns about delayed motor milestones and difficulty getting up from the floor. His parents report that Adam started walking at 18 months and continues to lag behind peers in activities like climbing stairs and running. Over the past year, they have also noticed that Adam uses his hands to push off his thighs when standing up, a behavior his parents find unusual. Adam’s parents report that he has no history of trauma or illness to explain his motor difficulties. He has frequent falls when walking and struggles to keep up with other children during play. They have also noticed that his calves appear unusually large, which they initially attributed to his growth. He has no complaints of pain, but he often seems fatigued after physical activity. Adam was born full-term with no complications during pregnancy or delivery. He has no significant medical history. There is no family history of neuromuscular disorders, but his maternal uncle reportedly had mobility challenges as a teenager. Physical Examination: General Appearance: Alert and cooperative. Musculoskeletal: Difficulty rising from a seated position; using hands to push off thighs to stand; calf hypertrophy noted bilaterally Neurological: Proximal muscle weakness in the hips and thighs. Reflexes are intact, and there are no sensory deficits. Diagnostic Workup: 1.Laboratory Tests: Creatine Kinase (CK): 15,000 U/L 2.Electromyography (EMG): Demonstrates myopathic changes. 3.Genetic testing confirmed the diagnosis. What is the genetic cause of this disorder? ( Duchenne muscular dystrophy (DMD)?)

Patient Profile Age: 32-year-old male Chief Complaint: Progressive weakness in legs History of Present Illness: One week ago: Developed a mild gastrointestinal illness with diarrhea and abdominal cramps, which resolved within 3 days. Four days ago: Began experiencing numbness and tingling in both feet, followed by progressive weakness in the lower extremities. Two days ago: Weakness worsened, spreading to the thighs and now affecting the arms. Today: Unable to walk without assistance due to bilateral leg weakness. Also reports difficulty gripping objects and mild shortness of breath. Medical History No significant past medical history No history of autoimmune diseases or recent vaccinations Family & Social History No family history of neuromuscular disorders Non-smoker, no drug use, occasional alcohol consumption Physical Examination General: Alert, no fever, mild respiratory distress Vital Signs: Blood Pressure: 124/80 mmHg Heart Rate: 88 bpm Respiratory Rate: 20/min Temperature: 98.6°F (37°C) Neurological Examination: Motor: Weakness (4/5) in proximal lower limbs, (3/5) in distal lower limbs; Mild upper limb weakness (4/5) Reflexes: Absent deep tendon reflexes (areflexia) in all extremities Sensation: Decreased vibratory and proprioception sense in the feet; Mild paresthesia in hands and feet, but no significant sensory loss Cranial Nerves: No facial weakness, normal eye movements Autonomic Findings: Mild tachycardia, reports occasional dizziness Diagnostic Workup 1.Lumbar Puncture (CSF Analysis): Elevated protein (95 mg/dL) with normal WBC count (albuminocytologic dissociation) 2.Nerve Conduction Studies (NCS) & Electromyography (EMG): Slowed conduction velocity and prolonged F-wave latencies (consistent with demyelination) 3.Serologic Tests: Positive Campylobacter jejuni serology; Normal CBC and metabolic panel What is the most likely diagnosis for this patient?