Parkinson's disease is a degenerative neurological disorder affecting movement. Idiopathic, or "pure," Parkinson's disease can be distinguished from a set of syndromes commonly referred to as "Parkinson's plus." According to Mayo Clinic, Parkinson's plus is a more severe, progressive form of the illness with shorter survival time.
People with Parkinson's plus experience the hallmark symptoms of idiopathic Parkinson's disease and one or more additional symptoms typical of a different neurodegenerative condition. It is important to remember that Parkinson's plus is not a single disease with a clear course, but rather a set of conditions that signal degeneration in multiple systems.
Idiopathic Parkinson's disease
The symptoms of idiopathic Parkinson's disease describe a standard or "pure" case with no secondary symptoms. Idiopathic Parkinson's disease is characterised by four hallmark symptoms. Patients have a tremor, or uncontrollable shaking, of the arms, legs, hands, and face. They also show bradykinesia, or slowed movement. People with idiopathic Parkinson's disease are stiff and unable to move quickly and fluidly. The final hallmark symptom is difficulty with balance and coordination.
Physicians diagnose individuals with these four hallmark symptoms and an ability to respond to the drug levo-dopa as having Parkinson's disease. The disease is progressive, as degeneration in the brain and body continue until the patient's death.
Dementia with Lewy Bodies
Dementia with Lewy bodies is a syndrome that, when combined with idiopathic Parkinson's disease, is considered a Parkinson's plus syndrome. Dementia with Lewy bodies occurs when a particular type of plaque begins accumulating in the brain regions controlling memory processes, cause nerve cell death. The disease is similar to Alzheimer's disease in that a patient progressively loses memory functions, but the two illnesses are differentiated by the type of plaque causing cell death.
Multiple System Atrophy
Multiple system atrophy is another condition that may be part of a Parkinson's plus syndrome. In addition to symptoms of Parkinson's disease, patients with multiple system atrophy show signs of dysfunction of the autonomic nervous system. These most often include problems with heart rate, blood pressure, breathing, digestion or sexual function. Multiple system atrophy remains rare but is a particularly aggressive syndrome with no known cure.
Corticobasal degeneration may appear with Parkinson's disease to form another syndrome of Parkinson's plus. The diagnosis of corticobasal degeneration is often difficult to make, as key symptoms overlap with symptoms of Parkinson's disease. The diagnosis can only be confirmed upon autopsy.
Symptoms of corticobasal degeneration include clumsiness and slowness of a limb on one side of the body. Patients may also show tremor and unsteadiness of gait, though these symptoms are also characteristic of Parkinson's disease. As corticobasal degeneration progresses, patients may also show difficulty generating speech, articulating speech, controlling a limb, swallowing, walking and moving, according to Mayo Clinic.
Progressive Supranuclear Palsy
Progressive supranuclear palsy is another syndrome that co-occurs with Parkinson's disease. Individuals with this condition have slowed movement and balance impairments, making a differential diagnosis between Parkinson's disease and progressive supranuclear palsy difficult. Patients with progressive supranuclear palsy may also have double vision, blurred vision, uncontrollable eye movements, impaired speech and difficulty swallowing. Having Parkinson's disease and progressive supranuclear palsy decreases a patient's remaining lifespan as these disorders make injury and infection more likely.