How is the disease diagnosed?
The process of diagnosing many diseases, and especially Gaucher disease, is not always straightforward. Often, the patient initially visits the physician for another problem such as the flu, for nonspecific pain, or for a routine physical. Although making a diagnosis of Gaucher disease is not difficult, some symptoms may resemble other diseases. The physician may first perform other tests to eliminate from consideration more common disorders. For example, in cases where patients have low platelet counts, physicians may first test for leukemia. If a patient complains of joint pain, the physician may first suspect arthritis. Sometimes a specialist physician, like a geneticist or hematologist, may be helpful in distinguishing the symptoms of Gaucher disease from other diseases with similar symptoms.
Gaucher disease might be suspected in a person who has an unexplained enlargement of the spleen or a tendency toward bleeding, or bone or joint pains, or spontaneous fractures. A pediatrician might make the diagnosis in a child complaining of abdominal discomfort or of frequent nosebleeds. A hematologist might make the diagnosis in a person with low blood or platelet counts. An orthopedist might diagnose Gaucher disease in the course of treating someone suffering from frequent unexplained fractures. Gaucher disease would be particularly suspected in people with blood relatives who have the disease. Physicians should be notified if there is a family history of genetic disease.
What can I expect after I have been diagnosed?
Patient Pathway at a Gaucher Centre: click here to see visual pathway
Diagnosis of a rare condition such as Gaucher disease is not always straightforward. A referral will be made to a specialist centre (known as Lysosomal Storage Disorders Units) if a patient develops signs and symptoms associated with the disorder warranting further investigation. Others may be referred following the diagnosis of another family member and genetic screening has been recommended to identify other affected individuals within the family, particularly in brothers and sisters. Referrals also come from other hospitals where a confirmed diagnosis of Gaucher has already been established and expert advice on management of the patient is sought.
The first point of contact for patients and relatives is usually with one of the specialist nurses who will arrange for an early appointment to attend the clinic for a range of diagnostic tests, medical assessment, genetic counselling, advice on current treatment options and the systems in place for delivery of treatment. Even before the first visit to clinic, the centres will offer a telephone help line providing advice on Gaucher and everything you may need to know about the services available.
The actual diagnosis of Gaucher is relatively simple to make as it can be made on a blood test sample which measures the level of the enzyme gluco-cerebrosidase (known to be deficient in Gauchers disease) in white blood cells. Because Gaucher is an inherited genetic disorder a blood sample to analyse the DNA will also be taken to confirm the diagnosis and identity the particular mutation, there are several known genotypes (changes in the gene) associated with Gaucher and the type of mutation may be helpful in predicting the severity of the condition, some genotypes predict a mild form, others indicate that the symptoms may prove more serious if left untreated. These blood tests will be taken at the first attendance at the clinic to confirm or exclude Gaucher. Because samples are taken for DNA analysis, informed written consent will be required from the patient before the sample is obtained. For those younger than 16 years of age, a parent or guardian may sign the consent.
In the clinic or even over the phone, the nurses and doctors will provide a clear and understandable explanation of what causes the disorder and describe the typical signs and symptoms involved. The inheritance pathway will be explained so that other ‘at risk’ family members can be identified. They will explain how the condition is treated and monitored. Not all people with Gaucher will necessarily need treatment since severity varies widely and many have a milder form which may never require treatment merely needing regular monitoring to observe for signs of progression. If there is evidence that the condition has progressed over time in someone not previously on treatment, then treatment options and recommendations can be discussed with the team.
Because Gaucher affects a number of organ systems there will be several tests and investigations arranged to determine the level of effect on the bones, bone marrow, liver size and function, spleen size and function. Occasionally the lung can also be affected although this is less common. The later or adult onset type of Gaucher does not usually affect the neurological and central nervous system but tests and assessments to exclude neurological involvement will also be performed. The advantage of attending a specialist centre is that there will be access to a wide range of clinicians, surgeons and services with expert knowledge of how Gaucher can affect the various systems.
A new diagnosis of Gaucher, especially if no one else in the family has previously been identified can come as a shock. The team at the centre will be there to help and support you through the process of diagnosis right from the beginning. The staff are specifically assigned to the service and you will receive continuity of care often dealing with the same staff members throughout diagnosis to treatment and long term follow up.
During the first few outpatient visit to the Gaucher clinic a newly diagnosed patient can expect to undergo the following tests as part of a typical assessment: click here to see the list of tests.
Treatment - As soon as the results of these tests (which should all be available within 1-2 weeks of testing a follow up appointment will be arranged to discuss all the test results with the doctors and nurses who will advise you if treatment is advocated. There are currently 3 licensed treatments available for Gaucher: Enzyme replacement therapy (ERT) with Cerezyme® (Imiglucerase) (Genzyme),Vpriv (velaglucerase alfa) (Shire Human Genetics) and Substrate reduction therapy (SRT) with Zavesca® (Miglustat) (Actelion). ERT is given by infusion every week or every 2 weeks. Zavesca is an oral preparation with dosing given three times daily.
If the treatment option is to start ERT the nurses will arrange for a short stay admission to the day care unit as an outpatient to receive the first few infusions. ERT is generally well tolerated and the infusion time is quite short at an average duration of 60 to 90 minutes. Provided the infusion is tolerated without any significant side effects then treatment can switch to home care provided by one of the commercial home care companies contracted by the hospital. The nursing staff are skilled at blood taking, cannulation and administration of intravenous therapies, if you wish to learn how to self administer ERT (and many patients do) then the hospital and home care nurses will undertake a training course to teach you or a family member how to do this. Not all patients prefer this option and a local hospital or clinic will be found for them to attend to receive their infusions.
Most, if not all the visits to hospital for treatment and assessment can be accomplished on an outpatient basis, it is very unusual to require an admission to hospital.
Follow up appointments are to assess response to treatment in those patients on ERT or SRT. These are usually every 2 - 3 months initially and then 4- 6 monthly once the disease has stabilized. More frequent visits may be required initially if the platelet count is very low.
For patients who travel long distances from the centres then a shared care arrangement can be organized with a local hospital for interim assessments.
The centres offer a holistic approach to care and internal referrals to a wide range of multidisciplinary healthcare professionals is available and are complementary to the LSDU team. These are typical examples of the specialists available:
•Orthopaedic Surgeons: For advice and surgical intervention such as hip replacement and revision of previous joint replacement.Radiologists: To interpret and report on imaging scans such as MRI, X-Ray, CT and ultrasound. They will have specific knowledge of how Gaucher affects the organs and skeletal system. Will review the follow up imaging to report response to treatment over time or identify any signs of disease progression which may prompt the start of treatment or signal the need to increase the dose or frequency or ERT/SRT or switch to another treatment.
•Anaesthetists and Clinical Nurse Specialists: Who specialise in pain management. Some patients with severe skeletal involvement may suffer from both acute and chronic bone and joint pain. Doctors (unsually anaesthetists) and nurses specialising in the management of pain are available to provide advice and can prescribe analgesia tailored to the specific needs of individual patients.
•Haemostasis Specialists: People with Gaucher frequently have abnormal clotting function this may be due to deficiencies in clotting factors such as factor X1. Doctors specialising in this area may be called upon to offer expert advice if a Gaucher patient is about to undergo a surgical or dental procedure. During pregnancy in Gaucher, patients who are known to have clotting abnormalities will be monitored by these specialist services and laboratories during pregnancy, birth and post natal period.
•General Surgeons: Provide general surgical procedures within the specialist centres ensuring that the specialist Gaucher team will be on site to provide expert advice on management during the procedure, for instance gallstones occur quite frequently in Gaucher and if symptoms are debilitating then surgical intervention may be indicated.
•Hepatology: Physicians specialising in the effect of Gaucher on liver function. Severely affected individuals may have liver involvement such as cirrhosis. Since the availability of effective treatment it is now rare for this to develop.
•Obstetric Services: Pregnancy can sometimes place an additional stress on women who have Gaucher disease and it is useful to have specialist input and support from the Gaucher team during the pregnancy through to delivery of the baby. The decision to continue or stop ERT during the pregnancy can be discussed with your medical team and obstetrician. For those patients planning to give birth at their local hospital a shared care plan will be arranged with the local obstetric team.
Because Gaucher is a rare condition which may require long term, perhaps life long treatment, follow up and continuity of care is very important to patients and family. The specialist centres are able to provide this continuity in a holistic manner. Patients will come to know their team well as they are likely to meet the same staff each time. Patients find reassurance in the knowledge that they are free to contact them through the helpline at any time. Many people affected by Gaucher express frustration when having to explain their condition over and over again to other medical professionals they may consult outside the specialist centre, a direct route to the Gaucher clinic is helpful to patients and other doctors and dentists involved in their general care.
Research and Development - Many of the centres are actively involved in research, the aim is to gain more information about the natural history of Gauchers and to try and improve treatment. Information about clinical trials will be available to patients who may wish to participate in these studies sometimes involving new drugs for Gaucher.