Creutzfeldt-Jakob Disease (CJD), an extremely rare and rapidly evolving neurological condition, gained prominence after the diagnosis of aviation specialist and influencer Lito Sousa. This disease causes accelerated degeneration of the brain, with severe impacts on memory, behavior and motor coordination, presenting a great challenge for medicine due to its complexity.
What is Creutzfeldt-Jakob disease and how does it manifest itself
Creutzfeldt-Jakob Disease is a neurodegenerative condition caused by prions, proteins that take on an abnormal shape. When this occurs, they induce other healthy proteins in the brain to also modify their structure. This process leads to an accumulation of abnormal proteins, resulting in progressive damage to brain cells and a spongy appearance in the affected tissue.
On the same topic: Creutzfeldt-Jakob disease: rarity and challenges for an accurate diagnosis
- Memory loss
- Significant changes in behavior
- Difficulty walking and imbalance
- Lack of motor coordination
- Involuntary movements
With an estimated global incidence of between 1 and 2 cases per million inhabitants annually, CJD is characterized by its remarkably rapid progression, differentiating it from other dementias that evolve over many years.
Why Creutzfeldt-Jakob Disease Is Considered So Uncommon
The extreme rarity of CJD still intrigues scientists, especially the sporadic form, which has no identified cause for the initiation of protein transformation. However, neurologist Jerusa Smid, from the USP Hospital das Clínicas and the Emílio Ribas Institute, suggests that the data known in Brazil may not reflect the real incidence of the disease. According to her, CJD may be more frequent than official records indicate, leading to underreporting.
Between 2005 and 2021, the Ministry of Health notified 1,576 suspected CJD, of which 547 were confirmed and 457 discarded. A third of the cases, 572, remained without final classification. This gap in Brazilian data raises questions about the country’s surveillance and diagnostic capacity, compared to nations with more structured health systems.
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The difficulty in early diagnosis and the similarity with other conditions
One of the biggest obstacles in coping with CJD is the absence of a unique initial symptom, which makes it easy to confuse it with other more common neurological diseases. The initial signs of Creutzfeldt-Jakob may resemble those of encephalitis, autoimmune diseases, or other forms of rapidly progressing dementia.
Professor Marcio Luiz Figueredo Balthazar, from the Department of Neurology at the Faculty of Medical Sciences at Unicamp, highlights that, unlike Alzheimer’s – which can take years or decades to evolve – CJD sets in and progresses quickly, with important changes appearing within a few months. The rapidity of progression is a clue, but it is not enough to confirm the diagnosis, which requires a detailed investigation to rule out treatable conditions.
Essential exams to identify the disease and its challenges in Brazil
The investigation of CJD requires a combined approach of different tests, as there is no routine test that, alone, resolves the diagnosis in all patients. Neurologists rely on the patient’s medical history and a series of assessments, including:
- Brain MRI:It may reveal characteristic patterns of the condition, strengthening suspicion.
- Lumbar puncture:Analysis of CSF, the fluid that surrounds the brain and spinal cord.
- RT-QuIC (Real-Time Quaking-Induced Conversion):A highly specific test that looks for evidence of abnormal prion protein in the CSF.
- Electroencephalogram (EEG):Records electrical activity in the brain.
- Other blood and CSF tests:Essential to rule out other encephalitis, autoimmune diseases, infections and metabolic changes that can mimic CJD.
RT-QuIC represents a significant advance, with specificity approaching 100% in some studies. However, as pointed out by neurologist Jerusa Smid, its availability in Brazil is still limited, which adds a layer of complexity to the accurate diagnosis of the disease in the country.
Underreporting of cases of Creutzfeldt-Jakob disease in Brazil
The inherent rarity of Creutzfeldt-Jakob disease already imposes an initial barrier: the need for health professionals to consider CJD in their differential diagnoses. A neurologist may see thousands of patients with memory complaints and encounter only a few cases of the disease throughout his career.
Additionally, diagnostic tests require centers with greater infrastructure and expertise, which is not always available in all regions of Brazil. The country’s own official records, with more than a third of notifications without a final classification reported in the period from 2005 to 2021, reinforce the idea that surveillance and identification of the disease still face considerable limitations. Experts emphasize the importance of a quick and careful investigation for rapidly progressing dementias, in order to ensure a correct diagnosis and rule out other treatable causes.