This book describes Microscopic Polyangiitis, Diagnosis and Treatment and Related Diseases
Microscopic polyangiitis (MPA) is a rare disease, the result of blood vessel inflammation (vasculitis) which can injure organ systems.
The organs most often affected by MPA are the kidneys, lung, nerves, skin, and joints.
MPA has many frequent features with another type of vasculitis called granulomatosis with polyangiitis (GPA, formerly called Wegener's Granulomatosis), and treatment methods for these illnesses are the same.
Vasculitis indicates inflammation of the blood vessels.
When inflamed, the blood vessel wall may become weakened and balloon forming an aneurysm or become so thin that it bursts resulting in bleeding into the tissue.
Vasculitis can also produce blood vessel narrowing to the point of closing off the vessel entirely.
This can induce organs to become damaged from loss of oxygen and nutrients that were being supplied by the blood.
MPA affects small to medium-sized blood vessels, which directly indicates the type of tissue damage that is seen in this disease.
Causes:
The cause of MPA is not known.
MPA is not a form of cancer, it is not infectious, and it does not normally happen within families.
MPA is obviously a disorder that is mediated by the immune system
MPA is often linked with anti-neutrophil cytoplasmic antibodies (ANCA), antibodies aimed against certain constituents of white blood cells
In MPA (microscopic polyangiitis), the ANCA are aimed mainly against to specific proteins: myeloperoxidase (MPO) and proteinase 3 (PR3).
Symptoms:
Because many different organ systems may be affected, a wide variety of symptoms and signs are possible in MPA.
Patients who have MPA may feel generally ill and tired with fever, loss of appetite and weight.
They normally have symptoms linked to involvement regions such as rashes, muscle and joint pain.
When MPA affects the lungs, the patients may have shortness of breath or coughing up of blood.
MPA affecting the nerves may induce an abnormal sensation followed by numbness or weakness.
A combination of these symptoms may happen.
Kidney disease produced by MPA often does not produce symptoms.
The inflammation of the kidney may not be obvious to the patient until the kidneys start to stop working.
Diagnosis:
Suspicion for MPA diagnosis is based on evidence taken from a range of sources, such as:
1. Medical history to look for the evidence of MPA symptoms
2. Physical examination to determine locations of organ involvement and to rule out other illnesses that may have a similar appearance
3. Blood tests to look for locations of organ involvement and testing for antineutrophil cytoplasmic antibodies (ANCA)
A positive blood test for ANCA can indicate a suspected diagnosis of MPA.
The blood test does not by itself prove the diagnosis of MPA or determine the disease action.
A tissue biopsy may be required to make the diagnosis of MPA
Treatment
Medicines that suppress the immune system are the main basis of treatment for MPA.
People with MPA are normally treated with corticosteroids combined with an immunosuppressive medicine such as cyclophosphamide or rituximab
In patients who have less serious MPA, corticosteroids and methotrexate can be given at first
If disease action can be entirely "turned off," this is called "remission."
Once it is definite that the disease is becoming better, the doctors slowly decrease the steroid dose and hope to stop it entirely.
When cyclophosphamide is given, it is only taken until the time of remission (3-6months) after which time it is changed to another immunosuppressive agent, such as methotrexate, azathioprine, or mycophenolate mofetil to maintain remission.
TABLE OF CONTENT
Introduction
Chapter 1 Microscopic Polyangiitis
Chapter 2 Causes
Chapter 3 Symptoms
Chapter 4 Diagnosis
Chapter 5 Treatment
Chapter 6 Prognosis
Chapter 7 Granulomatosis Polyangiitis
Chapter 8 Vasculitis
Epilogue
