Primary progressive multiple sclerosis is a well-recognized form of multiple sclerosis that is characterized by progressive damage to the central nervous system (CNS) and subsequent decline in overall functioning and quality of life [1] [2] [3] [4]. The exact pathogenic mechanism by which neuronal degeneration occurs, however, remains unclear [1] [4]. It is recognized in about 10-15% of all cases suffering from MS and is one of the rare entity that equally affects both genders [1] [5] [4] [6] [7]. In fact, some studies propose that males are more frequently affected than females and that MS patients are more likely to develop PPMS at an older age [1] [2] [7]. Compared to relapsing-remitting multiple sclerosis (RRMS), which encompasses the vast majority of MS patients and presents with optic neuritis and other isolated spinal cord/brainstem abnormalities [2], the clinical presentation of PPMS is comprised of two main symptoms - spastic paraplegia (often described with an unclear sensory level) and ataxia [2] [5]. These signs appear due to progressive atrophy of the spinal cord and the cerebellum, whereas the appearance of brainstem abnormalities, visual deficits, sexual dysfunction, cognitive decline, and inability to maintain sphincter control, are less commonly reported in PPMS [1] [2] [7]. Primary progressive multiple sclerosis has a poor prognosis than other types of MS, mainly because of a delayed diagnosis and an aggressive neurological deterioration [5] [7].

Because the various clinical forms of MS might be indistinguishable in their initial stages [2], particularly the different types of progressive MS, the physician, with his/her ability to obtain a detailed patient history and conduct a thorough physical examination, plays a crucial role in recognizing MS early on. Firstly, key information regarding the presence of symptoms, their duration, as well as progression, should be obtained, followed by a meticulous neurological evaluation. In recent years, diagnostic criteria for identifying PPMS have been designed and consist of the following [2] [4] [5] [7]:

• Progression of the disease for at least a period of 1 year.
• MRI findings - Either 9 lesions on T2-weighted studies or ≥ 4 lesions on T1-weighted studies in the brain, each exhibiting positive visual evoked potentials (VEP), or at least 2 focal spinal cord lesions seen on T2-weighted studies. Two out of three of the mentioned findings are required for the diagnosis of PPMS [3].
• The presence of oligoclonal bands or abnormally high levels of immunoglobulin (Ig) G antibodies in the CSF.

There is no cure for PPMS, but treatment focuses on managing symptoms and slowing disease progression. Medications such as ocrelizumab have been approved for treating PPMS and can help reduce the rate of disability progression. Physical therapy and rehabilitation are important for maintaining mobility and function. Symptomatic treatments, such as muscle relaxants and pain management, are also used to improve quality of life.

The progression of PPMS varies among individuals. Some patients may experience a slow progression of symptoms, while others may see a more rapid decline. The overall prognosis depends on the severity of symptoms and the effectiveness of treatment in managing disease progression. While PPMS can significantly impact daily life, many patients continue to lead active and fulfilling lives with appropriate management.

The exact cause of PPMS is unknown, but it is believed to involve a combination of genetic and environmental factors. The disease is characterized by the immune system mistakenly attacking the protective covering of nerve fibers, known as myelin, leading to nerve damage. This process disrupts communication between the brain and the rest of the body.

PPMS accounts for approximately 10-15% of all MS cases. It typically presents in individuals in their 40s or 50s, and unlike other forms of MS, it affects men and women equally. The prevalence of MS varies geographically, with higher rates observed in regions farther from the equator.

In PPMS, the immune system attacks the myelin sheath, the protective covering of nerve fibers in the central nervous system. This leads to inflammation and the formation of scar tissue, or sclerosis, which disrupts nerve signals. Over time, this damage results in the progressive worsening of neurological function.

Currently, there are no known methods to prevent PPMS. However, maintaining a healthy lifestyle, including regular exercise, a balanced diet, and avoiding smoking, may help manage symptoms and improve overall health. Ongoing research aims to better understand the disease and develop preventive strategies.

Primary Progressive Multiple Sclerosis is a form of MS characterized by a gradual worsening of symptoms without periods of remission. Diagnosis involves clinical evaluation and diagnostic tests, while treatment focuses on managing symptoms and slowing progression. Although the cause is unknown, a combination of genetic and environmental factors is believed to contribute to the disease. While there is no cure, effective management can help patients maintain a good quality of life.

If you or someone you know is experiencing symptoms such as difficulty walking, muscle stiffness, or balance issues, it is important to seek medical evaluation. PPMS is a chronic condition that requires ongoing management, but with the right treatment and support, individuals can lead active and fulfilling lives. Understanding the disease and working closely with healthcare providers can help manage symptoms and improve quality of life.

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