IMMUNE SYSTEM DISORDERS
Disorders of the Immune System fall generally in three categories:
- Overactive or inappropriate immune response.
- Deficient immune response.
- Autoimmune (self-attacking) response.
Asthma and allergies are examples of an overactive immune system reacting to a non-threatening foreign substance.
Immune deficiencies (immunodeficiencies) and autoimmune disorders are generally more serious and can be life-altering.
When one of the parts of the immune system is missing or does not work well, we say that the immune system is deficient. Most often this involves missing or defective T- or B-lymphoctyes or inadequate production of antibodies. The result is that the body is vulnerable to infections that might otherwise be easily defeated.
Immunodeficiencies can be “Primary”, i.e., present at birth and usually genetic, or “Secondary”. Secondary Immunodeficiencies have many causes, including disease, malnutrition, aging, certain medications, chemo- and radiation therapy, and stress. Probably the most well-known cause of immunodeficiency, though not the most common, is the Human Immunodeficiency Virus (HIV), which can cause AIDS (Acquired Immune Deficiency Syndrome).
There are some 185 Primary Immunodeficiencies recognized by the World Health Organization. Most common are those involving the production of antibodies and are called Primary Antibody Deficiencies (PAD’s). These disorders vary greatly in their underlying defects, but many of them can be managed and their symptoms mitigated by regular infusions of immunoglobulin.
Kedrion’s ongoing research and development has resulted in several immunoglobulin therapies for these conditions. Replacement therapy with immunoglobulin in primary antibody deficiencies increases life expectancy and reduces infection frequency and severity.
1. Abbas K. et al. “Le basi dell’immunologia. Fisiopatologia del sistema immunitario”. Ed. Masson Elsevier 2006.
The human body can sometimes become its own worst enemy. For reasons still not fully understood the human immune system can lose some of its ability for distinguishing between self and non-self and begin attacking normal healthy cells in the body. This is a condition known as autoimmune disease.
There are many autoimmune diseases that affect millions of people and their incidence seems to be growing worldwide.
The following Autoimmune Diseases are ones for which intravenous immunoglobulin (IVIg) therapy is indicated and approved:
1. Idiopathic thrombocytopenic purpura (ITP). Also known as immune thrombocytopenic purpura or autoimmune thrombocytopenic purpura, ITP is an autoimmune bleeding disorder resulting when the immune system attacks its own blood platelets, which are important to the clotting process. For reasons not well understood, lymphocytes produce antibodies that attach to the platelets, which then do not clot effectively and are subsequently recognized as “foreign” and destroyed in the spleen. Frequent and abnormal bleeding is typical and often results in many small bruises that can look like a rash (purpura).
Children are generally affected with an acute form of the disorder that resolves spontaneously in a few months while in adults it is usually a chronic condition requiring long term treatment. The disease is rare, with an incidence of 3 cases per 100,000 inhabitants per year in those aged under 16 years and 1.6 to 2.68 cases per 100,000 inhabitants per year in adults, with a slight female preponderance.
1. Navarro RP et al.; Considerations for the Optimal Use of Immunoglobulin. Am J Manag Care. 2012;18:S67-S78
2. Abrahamson PE. The incidence of idiopathic thrombocytopenic purpura among adults: a population-based study and literature review. Eur J Haematol..2009 Aug;83(2):83-9.
2. Kawasaki disease. Also known as mucocutaneous lymph node syndrome, is a form of vasculitis characterized by inflammation of blood vessels throughout the body. It primarily affects children under the age of five (and rarely over the age of eight).
With proper treatment the prognosis for these children is good, but without treatment about a quarter of them will develop cardiac problems, including coronary artery aneurysms. Kawasaki disease has become the leading cause of acquired heart disease in children in the developed world.
The cause of Kawasaki Disease is still unknown with researchers divided on whether it is an infection or an autoimmune response, but effective treatment includes primarily intravenous immunoglobulin.
1. Uehara R, Belay ED. “Epidemiology of Kawasaki disease in Asia, Europe, and the United States” J Epidemiol 2012; 22 (2): 79-85
2. Takahashi K et al.; Pathogenesis of Kawasaki disease. Clinical and Experimental Immunology, 2011; 164 (Suppl. 1): 20–22
3. Newburger JW. Diagnosis, treatment, and long-term management of Kawasaki disease: a statement for health professionals from the Committee on Rheumatic Fever, Endocarditis, and Kawasaki Disease, Council on Cardiovascular Disease in the Young, American Heart Association. Pediatrics. 2004;114:1708–1733
1. Guillain-Barré syndrome. This is a rare (affecting just 1 -2 people in 100,000) autoimmune disease in which the immune system attacks the myelin or outer covering of nerves (and sometimes the nerves themselves) of the peripheral nervous system. The damage leads to tingling and weakness in the legs and can proceed to even life-threatening paralysis.
Symptoms generally reach their most severe within days or weeks when they stabilize for a period of days, weeks or even months. Most people recover from even the most severe cases, but recovery can take as little as a few weeks or as much as a few years. The cause of the autoimmune response is unknown but it is sometimes triggered by infection, surgery or vaccination.
One treatment for Guillain-Barré syndrome that can reduce symptoms and hasten recovery is high dose immunoglobulin therapy.
2. Chronic inflammatory demyelinating polyneuropathy. CIDP can be thought of us a chronic form of the autoimmune disorder Guillain-Barré syndrome caused by demyelination of peripheral nerves, resulting in loss of sensation, motor weakness, and sensory symptoms.
Its estimated prevalence ranges from 0.8 to 8.4 per 100,000 people. CIDP is often disabling with over 50% of patients having temporary disability and about 10% eventually becoming persistently disabled or dying because of the disease.
The cause of CIDP remains unknown, but there are data supporting an immune pathogenesis. Plasmapheresis (plasma exchange), oral corticosteroids and intravenous immunoglobulin (IVIg) therapy are effective treatments, but should be started early to avoid permanent nerve damage.
1. Pithadia AB et al.; Guillain-Barre syndrome (GBS). Pharmacological Report 2010; 62: 220 – 232
2. Köller H et al.; Chronic inflammatory demyelinating polyneuropathy. N Engl J Med.2005 Mar 31;352(13):1343-56.
3. Mahdi-Rogers M et al.; Overview of the pathogenesis and treatment of chronic inflammatory demyelinating polyneuropathy with intravenous immunoglobulins. Biologics. 2010 Mar 24;4:45-9.
4. E.Nobile Orazio. Intravenous immunoglobulin versus intravenous methylprednisolone for chronic inflammatory demyelinating polyradiculoneuropathy: a randomised controlled trial. Lancet Neurol 2012; 11 (6): 493-502
Passive immunization employs preformed antibodies provided to an individual that can prevent or treat infectious diseases. There are several situations in which passive immunization can be used: for persons with congenital or acquired immunodeficiency; prophylactic administration when there is a likelihood of exposure to a particular infection; or treatment of a disease state already acquired by the individual.
1. Raab CP. Passive immunization. Prim Care. 2011 Dec;38(4):681-91
Chronic hepatitis B virus (HBV), a liver infection, affects about 400 million people worldwide, and some 600,000 deaths each year are attributable to the disease. It is associated with cirrhosis and liver cancer, resulting in a lifetime risk of HBV-related death of 25-40%. Liver transplantation is often the only viable treatment option for patients with complications.
But liver transplantation can be frequently followed by HBV reinfection, resulting in rapidly progressing liver disease and significantly decreased overall survival. Reinfection can be effectively prevented by administration of anti-hepatitis B immunoglobulin (HBIg) alone or, more recently, in combination with antiviral nucleoside/nucleotide analogs. This preventive regimen reduces the risk of a recurrence of HBV infection and thereby the need for retransplantation..
Before its introduction, reinfection with HBV after transplantation occurred in more than 80% of recipients and the 5-year graft and patient survival rates were only 50%. Now, with the use of the HBIg/nucleoside/nucleotide analogue prophylaxis, transplant programs in North America and Europe can expect prevention of HBV recurrence in greater than 90% of their patients.
Hepatitis B is contagious, but it can be transmitted from mothers to infants at the time of birth. This transmission can be markedly reduced by the immediate postpartum administration of HBIg to the infant either alone or, as currently recommended, with commencement of hepatitis B vaccine.
1. Nair S, Perrillo RP. In: BoyerTD, ed: Hepatology (4th edn). Philadelphia: Saunders, 2003: 959.
2. Realdi G, Fattovich G, Hadziyannis S, et al. Survival and prognostic factors in 366 patients with compensated cirrhosis type B: a multicenter study. The Investigators of the European Concerted Action onViral Hepatitis (EUROHEP). J Hepatol 1994; 21: 656^666.
3. Arianeb Mehrabi, “The role of HBIg as hepatitis B reinfection prophylaxis following liver transplantation” Langenbeck's Archives of Surgery June 2012, Volume 397, Issue 5, pp 697-710.
4. American Academy of Pediatrics. Hepatitis B. In: Peter G, editor. 1997 Red Book. Report of the Committee on Infectious Diseases. 24th ed. Elk Grove Village, Ill: American Academy of Pediatrics; 1997. pp. 247–260.
HEMOLYTIC DISEASE OF THE NEWBORN
Also called erythroblastosis fetalis, hemolytic disease of the newborn (HDN) is a condition that can arise when a mother and her unborn child have different and incompatible blood types. If even a few of the fetus’s red blood cells cross over the placenta and get into the mother’s circulation during the pregnancy, they are recognized by her immune system as “foreign” and it will produce antibodies to attack them. If these antibodies cross back over into the fetus, they will begin to destroy fetal red blood cells.
Since it takes time for antibodies to develop, the first child might not be seriously affected, but the mother’s immune system will now be sensitized to these incompatible red blood cells and subsequent pregnancies involving similar incompatibility will be seriously threatened.
The most serious type of HDN is Rh incompatibility in which the mother has Type Rh Negative blood and the fetus, Rh Positive.
Although HDN can be extremely serious, it is rare and preventable.
Passive immunization with anti-D antigen Immune Globulin protects Rh(D)-negative women from sensitization against Rh(D)-positive red blood cells.
1. Liumbruno et al. The role of antenatal immunoprophylaxis in the prevention of maternal-foetal anti-Rh(D) alloimmunisation. Blood Transfus 2010; 8:8-16
2. Bowman JM. Controversies in Rh prophylaxis: who needs Rh immune globulin and when should it be given? Am J Obstet Gynecol 1985; 151: 289-94.
3. Clarke CA, Donohoe WTA, McConnell RB, et al. Further experimental studies on the prevention of Rh haemolytic disease. Br Med J 1963; 1: 979-84.
Tetanus is a serious disease affecting the nervous system and causing severe muscle contractions, especially around the jaw and neck (It is sometimes known as “lockjaw”). It is life-threatening without treatment.
Tetanus is contracted through a wound – especially a deep cut or puncture – that becomes contaminated by the tetanus bacterium, Clostridium tetani. These bacteria are ubiquitous in soil, dust and animal or human feces. Their spores germinate in the anaerobic environment of the wound and produce a potent neurotoxin, tetanospasmin, that impairs motor neurons controlling the muscles.
Fortunately, Tetanus can be effectively prevented by active immunization with Tetanus toxoid. For short-term, but immediate protection (passive immunization) or post-exposure treatment, Tetanus-specific immunoglobulin is effective.
1. Steven G. F. Wassilak, Katrina Kretsinger “Tetanus”. Bacterial Infections of Humans 2009, pp 813-832