One of the most frustrating things you will face during your CJD experience is obtaining a diagnosis for your loved one. They will undoubtedly undergo a vigorous testing regime of magnetic resonance imaging (MRI’s), electroencephalography (EEG’s), cat-scans, and a special analysis of the spinal fluid for the presence of a protein that is released from damaged or dying nerve cells, and all the while they will continue to deteriorate before your eyes. Unfortunately these tests are not sensitive enough to give a confirmed diagnosis of CJD . If a neurologist has 2 or 3 positive results however, the diagnosis is likely to be CJD.
The Diagnosing CJD section under ‘What is CJD’ provides details about the symptoms of CJD and the rapidity of these symptoms. It is important to note, though, that while someone may experience all of the “usual” symptoms, it is also highly probable that they will experience only some, which can make accurately diagnosing the disease difficult for the neurologists providing them care.
All health care professionals experienced with caring for patients with CJD will confirm that no two cases of CJD are the same. This not only makes diagnosis difficult but also makes the decision on where best the patient can be cared for complicated, as the timeframe for illness is hard to determine. The majority of patients with CJD will not survive more than 12 months, with the average duration of illness 3 to 6 months, but in some cases the disease progresses more rapidly and in other cases the survival time can be up to 2 years or even longer. Duration of illness can depend on the form of prion disease, ie GSS is known to have a much longer duration, or the phenotype of sporadic CJD. There is some anecdotal evidence that indicates the genotype of the patient may also influence age of onset or duration of illness.
Some families tell us that looking back they did notice subtle changes in personality or behaviour in the patient even going back a year or two prior to more physical symptoms occurring, ie visual disturbance, unsteadiness, lack of coordination, clumsiness, known clinically as cerebellar ataxia with memory loss and confusion eventually becoming a rapidly progressive dementia. There is also anecdotal evidence that indicates that these initial subtle changes sometimes occur following a stressful event, an operation or significant disturbance in the patient’s life. Are these triggers? There is no evidence to support that but families have reported apathy or depression following a stressful event that eventually seemed to lead to more physical and severe symptoms. Others report that the patient was health and well before developing a number of severe symptoms. These more severe symptoms are often the marker for the patient being considered symptomatic as they have led to a referral to a neurologist/specialist and a barrage of tests to try and establish a diagnosis.
The diagnostic process takes time and causes a lot of frustration for families as result after result come back as negative. Even the diagnostic tools which can give a good indication that the patient is suffering with CJD are not conclusive although in many patients positive results to the diagnostic tools described under the diagnostic section, combined with clinical appearance and a rapid decline, can give a good indication that the patient is suffering with a prion disease. In some cases results are negative but a biopsy or autopsy has confirmed CJD which again reinforces that these diagnostic tools are not conclusive.