Raising nurses' awareness of primary deficiency: primary immune deficiency is a term covering a large family of diseases and conditions in which the patient's immune system is compromised. Nurses can play an important part in ensuring early diagnosis.

AS A practising nurse, do you know enough about the normal immune system and what can go wrong? If your answer is no, then yon can help by increasing your knowledge in this area. Nurses are often the first point of contact for the patient suffering primary immune deficiency (PID). Nurses' awareness can promote early recognition of a family of diseases and may prevent serious long-term complications from immune deficiencies.

A world expert on PID, Jerry Winkelstein, a paediatrician and immunologist from John Hopkins Hospital in Baltimore, Maryland, recently spoke at a series of seminars in New Zealand to raise the awareness of the importance of early diagnosis of PIDs in children and adults. Early diagnosis is essential to prevent end organ damage such as bronchiectasis. The seminars were sponsored by KIDS Foundation, a not-for-profit organisation dedicated to supporting New Zealanders coping with PID conditions and educating health professionals and the public about this illness.

The following is an outline of the main points from the seminars, with emphasis on dispelling common myths associated with PIDs.

What is the normal immune system? To understand what can go wrong with the immune system, it is essential to understand the functions of the normal immune system. The immune system is an intricate system of cells and proteins that help protect the body from infection. It has two major functions:

1) To recognise foreign material, eg bacteria, virus, pollens, transplanted organs.

2) To react against foreign material, eg inflammation, killing or rejection.

It plays a critical role in defending against infection, determining the difference between self and non-self, and producing a normal inflammatory response.

The organs of the immune system are located in many parts of the body. (See illustration at right.) They are found in the thymus, the tonsils and adenoids, the spleen, the lymphatic circulation, lymph nodes, payer's patches and the bone marrow.

If you were to get a splinter in your thumb, then you would expect your immune system to respond to the foreign invasion. However, if your arm and hand were not supplied with components of the immune system and could not recognise and react to the splinter, the lack of an immune system would make the result quite different.

The components of the immune system consist of B cells, T-cells, Phagocytes and complement. The function of the B-lymphocytes is to turn into plasma cells to make immunoglobulin and present antigens (foreign material) to T-Lymphocytes. The function of T-Lymphocytes is to orchestrate the cells of the immune system to communicate with each other. T cells kill cells infected with viruses, arm phagocytic cells to better kill certain bacteria and fungi; and regulate the production of antibody B-Lymphocyte.

The complement system coats bacteria and fungi so a phagocyte can ingest them. Complement also punches holes in certain bacteria and stimulates inflammation. Phagocytic cells ingest and kill bacteria and fungi (see illustrations at fight) and remove dead cells and tissue. They also present antigens to lymphocytes.

What happens when the immune system does not work? A PID is a disorder in which the defect is found within or arises from the cells and tissues of the immune system. A secondary immune deficiency is one in which the defect occurs secondary to an outside agent such as drugs (chemotherapy, steroids), viruses (HIV), malnutrition, malignancies and radiation.

Immune deficiencies are a family of diseases with more than 115 different disorders identified. Most deficiencies are inherited as a single gene defect and disorders involve every component of the immune system. The first immune deficiency was identified in 1952 by Ogden Bruton and was named X-Linked Agammaglobulinemia or sometimes known as Burton's Agammaglobulinemia.

Primary Immune Deficiencies are classified as a family of diseases, which have many clinical presentations in common:

* increased susceptibility to infection

* abnormal inflammatory response/ autoimmune diseases, eg, Lupus, arthritis, and thrombocytopenia 

* positive family history of a previous PID.

Selective examples of PIDs

* Selective IgA Deficiency, which can affect 1/500 people.

* Common Variable Immune Deficiency (CVID) most often found in adults and affects both males and females.

* X-Linked Agammaglobulinaemia was the first identified PID. Only males are affected. It has an excellent prognosis if diagnosed and treated early.

* Severe Combined Immune Deficiency (SCID). It is famous as the "boy in the bubble" disease. Affects 1/60,000 live births and can be X linked and autosomal recessive. This is a fatal disease unless corrected by bone marrow or stem cell transplant.

* Chronic Granulomatosis Disease (CGI)) which is caused by a defect in the phagocytic cells, affecting 1/200,000.

* Terminal Complement Diseases, affecting 1/10,000.

Therapies for Immunodeficiency Diseases: Currently there are a range of treatments for these PIDs, and most individuals can lead a normal life. Less than 50 years ago this was not possible. The "boy in the bubble" was managed with isolation as the only available treatment, which was not sufficient for long-term survival. Specific treatments now include immunoglobulin replacement (intravenous and sub cutaneous), bone marrow transplant, cytokines and gene therapy. General therapies include antibiotics, anti-fungal drugs, anti-viral drugs, special diets, total parental nutrition and isolation.

Myths about PID

1) They are rare: As a family of diseases, they are more common than childhood leukemia or lymphoma

2) They are diseases of childhood: Some of the disorders present initially in adult life. In CVID the average age of onset of symptoms is 28 years, and age at diagnosis is 32 years. Most disorders can be treated successfully, resulting in survival into adult life.

3) Patients present as severely ill: Some of the disorders may have relatively mild clinical presentation, eg Selective IgA deficiency, C2 deficiency and C 5-9 deficiency. Some disorders present initially with relatively mild symptoms but progress to more severe symptoms.

What are the clinical presentations? There is no set "recipe" that leads to a diagnosis. It is important to look at the whole picture.

* The patient may seem to have an increased susceptibility to infection, eg unusual recurrent infection, unusual severe infection, unusual persistent or complicated infection or unusual low virulence of the organism.

* The patient may have an associated autoimmune, rheumatic, or inflammatory disorder: autoimmune disease, eg ITP; inflammatory bowel disease eg Crohn's Disease; dermatitis, eg excema; or Scardosis.

* The patient may have an associated syndrome. A clinical pattern of eczema and thrombocytopenia could indicate Whiskott Aldrich Syndrome. Hypocalcemia and cardiac defect could indicate Di George Syndrome and ataxia telangiectasia would indicate Ataxia Telangiectasia.

* The patient may have a positive family situation of x-linked recessive disorders.

Winkelstein also reported on a national survey of PID diseases reported by patients and their physicians, conducted by the Immune Deficiency Foundation hi the United States. Results were published in May 2001. The following is a summary of the survey.

* Most commonly re ported was CVID. followed by IgG Subclass.

* Least common were Ataxia Telangiectasir and Wiskott-Aldrich Syndrome.

* Most affected with PID were under the age of 18 years (10-15% were 24-64 years).

* Most patients were aged one to five years or 18-39 years at diagnosis.

* The majority of people were initially tested lot PID because of repeated infections.

* Only seven percent were diagnosed because of family history.

* 30 percent of the individuals were never hospitalized prior to diagnosis.

* 48 percent have never been hospitalised since diagnosis.

* 42 percent said they had no limitations, while nine percent had severe limitations.

Contributions of PID to other fields of medicine: Winkelstein concluded his seminars to nurses by identifying some of the significant therapies developed over the years as a direct result of research con ducted for the benefit of patients with PIDs.

Primary immune deficiency has provided valuable insight into the function of the normal immune system. Understanding of immune deficiencies enabled the AIDS virus to be identified. Research into PID has identified new and important genes and proteins of the immune system. The first bone marrow transplant was performed for a PID. Intravenous Immunoglobulin, which is now widely used for many conditions, was first used as a replacement therapy for a PID. There is ongoing re search into the role of gene therapy as a treatment for PID.

The process of phagocytosis 

Stage 1: Extending to embrace bacteria

Stage 2: Trapping the bacteria

Stage 3: Ingesting and chemical release to destroy bacteria.

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* For further information on PID, contact KIDS Foundation of New Zealand, ph 09 523 5560; free phone [phone]; email: [e-mail]; www.pidsnz.co.nz.

If you are involved in the care of patients with PID and are interested in becoming involved in a nurses' special focus group, contact Pauline Brown. She is planning a group to offer support and advice and keep members informed of advances in care/research, conferences and future events. Phone Pauline Brown at 09 307 4949 ext 5329; email [e-mail].

--Pauline Brown, RGON, BHSc, is clinical immunology nurse specialist at Starship Hospital, Auckland.