Q 2.27. Parkinson’s Disease

Mrs Merkel fight with Parkinson’s Disease

Case Study:

Mrs. Merkel, a 69-year-old retired schoolteacher, presents to the hospital with a two-year history of progressively worsening motor symptoms. She describes a resting tremor in her right hand, stiffness in her limbs, and difficulty initiating movements. Her family notes a subtle reduction in her arm swing while walking.

Neurological examination reveals a classic “pill-rolling” resting tremor, bradykinesia with a slight hesitation in her gait initiation, and rigidity in both upper and lower limbs. DaTscan imaging confirms the suspected diagnosis of Parkinson’s disease (PD) by showing a significant reduction in dopamine activity in the substantia nigra. Mrs. Merkel’s levodopa therapy is initiated, and her response is closely monitored, adjusting medication dosages as needed. Alongside pharmacological intervention, a tailored physical therapy plan is implemented to address mobility challenges and enhance Mrs. Merkel’s overall quality of life.

Educational sessions are conducted to empower both Mrs. Merkel and her family with a comprehensive understanding of PD, emphasizing the importance of ongoing care and support in managing this chronic neurological condition.

 

Summary on Parkinson’s Disease:

1. Overview of Parkinson’s Disease:

  • Definition: Parkinson’s disease (PD) is a progressive neurodegenerative disorder characterized by the degeneration of dopamine-producing neurons in the substantia nigra of the brain.
  • Key Feature: The loss of dopamine leads to disrupted communication between nerve cells, causing motor and non-motor symptoms.

 

2. Clinical Appearance:

  • Motor Symptoms:
    • Tremors: Resting tremors, rhythmic oscillations at rest.
    • Bradykinesia: Slowness in initiating and executing voluntary movements.
    • Rigidity: Increased resistance to passive limb movement.
    • Postural Instability: Impaired balance and coordination.
  • Non-Motor Symptoms:
    • Mood Changes: Depression and anxiety are common.
    • Autonomic Issues: Constipation, low blood pressure, and sweating abnormalities.

 

3. Diagnosis:

  • Clinical Assessment: Neurologists assess motor symptoms, their progression, and daily life impact.
  • Levodopa Trial: Positive response supports the diagnosis by temporarily alleviating symptoms.
  • DaTscan Imaging: This functional imaging technique shows reduced dopamine levels, aiding confirmation.
  • Exclusion Criteria: Rule out other conditions with similar symptoms through medical history and tests.

 

4. Pathophysiology Explanation:

  • Dopamine Deficiency: Progressive loss of dopaminergic neurons in the substantia nigra, affecting the basal ganglia.
  • Basal Ganglia Dysfunction: Disruption in the basal ganglia circuitry, impacting motor control and coordination.
  • Lewy Bodies Formation: Accumulation of abnormal protein aggregates, particularly alpha-synuclein, contributing to neuronal damage.
  • Neuroinflammation: Activation of microglia and inflammation in the brain may exacerbate neurodegeneration.

 

5. Expected MRI/CT Findings:

  • MRI: While MRI is typically normal in early-stage PD, advanced cases may show atrophy in the substantia nigra. It is more useful for ruling out other conditions. Loss of the normal swallow tail appearance of susceptibility signal pattern in the substantia nigra on axial imaging is perhaps the most promising diagnostic sign 
  • CT: Similar to MRI, CT is often normal in early stages but with advanced disease, non-specific generalised minor cerebral volume loss (atrophy) can be demonstrated. Both imaging modalities primarily assist in excluding other causes of symptoms.

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LOSS OF SWALLOW TAIL SING IN PARKISONS DISEASE

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This is a ‘Swallow tale’ image from 3T MRI scan

 

 

6. Treatment:

  • Medication, GOLD Standard : Levodopa is a fundamental medication in Parkinson’s disease (PD) management, serving as a precursor to dopamine, the neurotransmitter deficient in PD. By replenishing dopamine levels in the brain, levodopa mitigates motor symptoms like tremor, rigidity, and bradykinesia. Typically administered in combination with carbidopa to minimize peripheral side effects, levodopa’s efficacy is well-established, providing significant relief to PD patients. However, prolonged use may lead to motor fluctuations and dyskinesias, necessitating careful dosage adjustments and monitoring to optimize therapeutic outcomes while minimizing adverse effects. During treatment, Levodopa is taken multiple times a day (5-6) compeered to other treatments that require 1-3 doses normally, to provide good control.
  • Deep Brain Stimulation (DBS): Surgical implantation of electrodes in the subthalamic nucleus or globus pallidus to modulate abnormal neural activity.
  • Physical Therapy: Exercise and rehabilitation enhance mobility and alleviate symptoms.

 

7. Late stage management :

  •  In the advanced and late stages of Parkinson’s disease (PD), symptoms become increasingly severe and debilitating. Motor symptoms worsen often despite medication adjustments. Patients may experience motor fluctuations, with unpredictable periods of mobility and immobility, as well as dyskinesias, which are involuntary movements. Non-motor symptoms like cognitive impairment, hallucinations, and psychosis may also become more prominent, impacting quality of life.

 

  • Controlling the disease becomes challenging due to the unpredictable nature of motor fluctuations and dyskinesias, which can be difficult to manage with standard oral medications. In such cases, alternative delivery methods for medication may be considered. One option is a gastric pump for levodopa, which involves surgically implanting a pump into the abdomen. This pump delivers a continuous infusion of levodopa directly into the small intestine, providing more stable and consistent medication levels throughout the day. This method can help improve motor symptom control and reduce fluctuations, enhancing patients’ quality of life in the advanced stages of PD.

 

8. Mnemonic for Key Features:

  • Tremors, Slowness, Stiffness, Balance: “Tiny Squirrels Snuggle Blissfully.”

 

 

 

LITERATURE: https://radiopaedia.org/

 

 

Verified by Dr. Petya Stefanova