Five clinical manifestations have been described for common variable immunodeficiency [6]:

• Uncomplicated
• Autoimmune disorders
• Polyclonal lymphocytic infiltration
• Enteropathy
• Lymphoid malignancy

Each and every patient that has a medical history of CVID runs the risk of developing three specific complications: periodic infections, autoimmune diseases and cancer. The recurrent infections usually affect the respiratory tracts (upper/lower); otitis media, diarrhea, pneumonia, and sinusitis are the most commonly occurring infections [11]. Infections caused by rarely encountered organisms, such as prototheca algae, may also be seen [12]. Giardia lamblia infections are common amongst CVID patients, causing diarrhea and malabsorption.

CVID patients are also subject to severe chronic diarrhea due to both infectious and autoimmune causes, rather than GI malignancies. Young children may especially experience hindered growth because of the recurrent infections or GI tract conditions. In cases where the bronchi are often affected, bronchiectasis may occur, with permanent damage being an expected complication. Patients are most frequently infected with h.influenzae, s.pneumoniae, m.catarrhalis and s.aureus.

Approximately 1/4 of the patients with CVID suffer complications of the autoimmune spectrum[13], including rheumatoid arthritis, vitiligo, hemolytic anemia, thrombocytopenia and neutropenia [14] [15]. As far as malignancy is concerned, patients also run the risk of B-cell lymphomas, which has been linked to the Epstein-Barr virus.

• Generalized Lymphadenopathy

  Lymphoproliferative disorders such as generalized lymphadenopathy and/or splenomegaly are present in up to 40% of patients, and there is an increased risk of developing gastrointestinal and lymphoid malignancies, especially non-Hodgkin's lymphoma (see [orpha.net]

  Due to poor response to antibiotics and generalized lymphadenopathy, we decided to perform CT-neck, thorax, abdomen, and pelvis to lookout for possible hematological malignancies. [hindawi.com]

• Recurrent Infection

  Common variable immunodeficiency (CVID) is a heterogeneous disorder characterized by antibody deficiency, poor humoral response to antigens, and recurrent infections. [ncbi.nlm.nih.gov]

  English common variable immunodeficiency immune disorder characterized by recurrent infections and low antibody levels, specifically in immunoglobulin CVID acquired agammaglobulinemia acquired hypogammaglobulinemia common variable agammaglobulinemia sporadic [wikidata.org]

  Clinical presentation usually includes recurrent infections of the respiratory tract, mostly induced by capsular bacteria. [moh-it.pure.elsevier.com]

  CVID is distinguished by B-cell abnormalities, hypogammaglobulinemia and recurrent infections. [neurology.org]

• Anemia

  Complications: The complications include autoimmune manifestations, e.g. pernicious anemia, autoimmune haemolytic anemia, rheumatoid arthritis, primary hypothyroidism, idiopathic thrombocytopenic purpura, psoriasis, vitiligo, atrophic gastritis. [xpertdox.com]

  METHODS: We describe four women (mean age 54 years) with CVID associated with idiopathic thrombocytopenic purpura (ITP) (n=3) and autoimmune hemolytic anemia (AIHA) (n=1). [ncbi.nlm.nih.gov]

  Autoimmune disorders (eg, autoimmune thrombocytopenia, autoimmune hemolytic anemia or pernicious anemia, systemic lupus erythematosus, Addison disease, thyroiditis, rheumatoid arthritis, alopecia areata) can occur, as can malabsorption, nodular lymphoid [merckmanuals.com]

• Recurrent Bacterial Infection

  It results in recurrent bacterial infections. [icd9data.com]

  Common variable immunodeficiency (CVID) is a primary immunodeficiency characterized by hypogammaglobulinaemia, T-cell abnormalities and recurrent bacterial infections. [ncbi.nlm.nih.gov]

• Fever

  However, the NLRP12-associated periodic fever syndromes show a wide clinical spectrum, including patients without classical diagnostic symptoms. [ncbi.nlm.nih.gov]

  If there are symptoms suggestive of lymphoid malignancy such as fevers or night sweats, consider computed tomography (CT) chest/abdomen/pelvis to screen for lymphoma. Otherwise, routine testing is for diagnosis with serum immunoglobulins. [clinicaladvisor.com]

  They include malaise, headache, fever, urticaria, itch, nausea, abdominal pain, hypertension and hypotension. Headache may persist for several days after infusion. [dermnetnz.org]

• Weight Loss

  In addition to infections, symptoms can include diarrhea and weight loss, due to inflammation of the gastrointestinal tract. [medicinenet.com]

  More than half of patients present with diarrhea and 10% develop idiopathic malabsorption associated with weight loss. [medcraveonline.com]

  Signs and symptoms of CVID include: Breathing problems Chronic cough Diarrhea that causes weight loss Ear infections Frequent sinus infections Recurring lung infections, including pneumonia Get useful, helpful and relevant health + wellness information [my.clevelandclinic.org]

  […] infections of the respiratory tract, especially otitis media, pneumonia and sinusitis Bronchiectasis (lung damage) from recurring pneumonia Infection (eg giardia) or inflammation of the gastrointestinal tract with secondary symptoms of diarrhoea and weight [dermnetnz.org]

• Cough

  People may develop a chronic cough, cough up blood, or have difficulty breathing. [merckmanuals.com]

  Here we report the case of a 37 year-old man presenting to the emergency room with dyspnea, fever and cough; he developed respiratory failure requiring mechanical ventilation. [ncbi.nlm.nih.gov]

• Chronic Diarrhea

  We present the case of a patient with common variable immunodeficiency suffering a chronic diarrhea episode and who was diagnosed with ileocaecal Crohn s-like disease after performing intestinal transit, CT abdomen and colonoscopy with biopsy. [ncbi.nlm.nih.gov]

  So, in any patient suffering from chronic diarrhea unrelated to known causes, could have primary immunodeficiency. [medcraveonline.com]

  Clinical features Chronic diarrhea, malabsorption, recurrent GI giardiasis Microscopic (histologic) description Mucosa may resemble celiac sprue or be normal but always has reduced plasma cells and no IgA plasma cells May have lymphoid hyperplasia or [pathologyoutlines.com]

  In some patients, chronic diarrhea is the major symptom of the disease. [academic.oup.com]

• Failure to Thrive

  This case report describes a 10-year-old boy presenting with signs of common variable immunodeficiency (CVID), failure to thrive, impaired neurological development, and a history of recurrent mucocutaneous Candida infections. [ncbi.nlm.nih.gov]

  Possible poor growth or failure to thrive. T-Cell and Combined Immunodeficiency:. .. .. Presentation in early infancy.. .. .. Poor growth or failure to thrive.. .. .. Persistent oral thrush.. .. .. Opportunistic infection. Phagocytic Defects:. .. .. [hawaii.edu]

  […] to thrive diarrhea sinusitis pallor tympanic membrane perforation illness after live vaccines weight loss, night sweats, fevers edema alopecia, goiter, vitiligo eczema small/absent tonsils lymphadenopathy and hepatosplenomegaly history of celiac disease [bestpractice.bmj.com]

  Persistent diarrhea, chronic mucocutaneous candidiasis, and failure to thrive may occur in infancy. Blood transfusions can result in graft-versus-host disease and routine vaccinations in fatal infection. [medical-dictionary.thefreedictionary.com]

• Recurrent Diarrhea

  It is determined that Giardia lamblia is responsible for the recurrent diarrhea. The physician performs a serum analysis and finds normal levels of mature B lymphocytes. [medbullets.com]

  […] or chronic bacterial respiratory tract infections combined with recurrent diarrhea; 4) Bacterial infections of respiratory tract and/or recurrent diarrhea combined with severe generalized infections (septicemia, meningitis, osteomyelitis); 5) Any of [f1000research.com]

  In our investigated group, 50 out of 65 (76.9%) patients had recurrent diarrhea. [cvi.asm.org]

  Parasites, such as Giardia intestinalis, are responsible for recurrent diarrhea, whereas lymphoproliferation, villous atrophy, or inflammatory lesions are associated with chronic diarrhea. [academic.oup.com]

  In IgA deficiency, children and adults may present with the celiac-like syndrome, recurrent diarrhea with blunting of villi on jejunal biopsy leading to growth retardation in children.[25] 6. [ncbi.nlm.nih.gov]

• Acute Diarrhea

  The most frequent complication was acute diarrhea (in 67 patients). Identification of responsible pathogens detectable with use of stool examination or culture was easier than identification of responsible pathogens for acute respiratory infection. [academic.oup.com]

  The most common infections, before diagnosis and during follow-up, were pneumonia, acute diarrhea, acute sinusitis, and otitis media. [cvi.asm.org]

• Dental Caries

  All participants underwent examination for dental caries and periodontal disease. Blood and whole saliva samples were collected on the same day of the oral examination. [ncbi.nlm.nih.gov]

• Arthralgia

  Arthralgia, monoarticular or oligoarticular arthritis of the large joints with sterile effusions and septic arthritis may occur. Anaphylaxis or other severe reactions following transfusion of blood products may indicate an underlying IgA deficiency. [patient.info]

  Other findings less frequently reported included rash, arthralgias, myalgias, facial edema, and lymph node or liver test abnormalities, which can also occur in infectious meningitis, mainly of viral origin, with variable frequency. [doi.org]

• Alopecia

  Return to Article Details Common Variable Immunodeficiency and Type 1 Diabetes Mellitus in a 19-year-old Filipino Male with Alopecia Universalis [asean-endocrinejournal.org]

  Effect of IVIG on the hair regrowth in a common variable immune deficiency patient with alopecia universalis. Asian Pac J Allergy Immunol. 1999 Mar. 17(1):59-62. [Medline]. Kilic S, Ersoy F, Sanal O, Turkbay D, Tezcan I. [emedicine.com]

  The most common cutaneous manifestations of common variable immunodeficiency are: Bacterial skin infections, such as impetigo, cellulitis and boils Autoimmune diseases, such as vitiligo, alopecia areata, psoriasis, systemic lupus erythematosus and vasculitis [dermnetnz.org]

• Furunculosis

  Gingivitis, abscesses, skin infection, including cellulitis and furunculosis. Complement Defects:. .. .. Early complement deficiency: Sinopulmonary infection, autoimmune disease.. .. .. [hawaii.edu]

Patients usually exhibit decreased plasma levels of immunoglobulin A and G and, at some points, equally diminished IgM levels, without any other known cause for this phenomenon. T and B lymphocytes in the serum can be evaluated with the aid of monoclonal antibodies for immunofluorescence staining, with the help of CD19 and CD20 (B cells), CD3 (T cells), CD4 (helper T cells), and CD8 (suppressor T cells). Natural killer cells (also known as NK cells) and T cells can also be enumerated with the use of monoclonal antibodies against CD16, CD56 and CD57.

A high-resolution thoracic computed tomography (CT) scan can prove useful for the diagnosis of pulmonary abnormalities; the information it provides for this specific type of disease is far more useful than that of an x-ray or a test to evaluate lung function. Biopsy samples can be harvested from enlarged lymph nodes in order to rule out malignancy. Bronchoscopy can also be used.

Endoscopy is reserved for patients suspected of suffering from gastrointestinal complications. Lesions and infectious processes can be observed, alongside villous atrophy, infection with cryptosporidium and lambliosis that can be evaluated histologically. Submucosal tissue and lymph nodes are also histologically tested. The former may be infiltrated by plasma cells and the latter may have been subject to the following changes: reactive follicular or atypical hyperplasia and granulomatous inflammation.

Antibody levels are not assessed in patients that have received IV immune globulin (IVIG) during the previous 6 months or earlier, because the antibodies that will be detected are essentially IVIG products. Flow cytometry is also used to determine B- and T-cell count, so as to eliminate the possibility of other conditions causing immunodeficiency, in order to identify CVID versus a multiplicity of other similar conditions: X-linked agammaglobulinemia, multiple myeloma and chronic lymphocytic leukemia. CVID patients usually have a decreased count of class switched memory B cells or CD21+ cells. Protein electrophoresis is used as a screening procedure to exclude monoclonal gammopathies (eg, myeloma), which may be also present with diminished levels of other immunoglobulins.

CVID patients should follow a yearly follow-up plan including spirometry, liver function tests, CBC and a metabolic check up. In cases of impaired lung function, a CT will help investigate the issue appropriately. Screening tests carried out to relatives of the patients are not a recommendation and they are reserved for patients with a given family history of the disease.  

In a nutshell, common variable immunodeficiency is diagnosed by observing considerably low levels of IgG and IgA and/or IgM, alongside a decreased antibody production or lack thereof [16]. CVID is fundamentally a condition that is diagnosed upon exclusion of other similar disorders.

• Chest X-Ray Abnormal

  SCID is typically diagnosed by clinical features: absence of lymph nodes and tonsils, lymphopenia, absence of a thymic shadow on chest x-ray, abnormal T, B, NK cell enumeration with flow cytometric analysis, abnormal in vivo T cell function studies with [hawaii.edu]

• X-Ray Abnormal

  SCID is typically diagnosed by clinical features: absence of lymph nodes and tonsils, lymphopenia, absence of a thymic shadow on chest x-ray, abnormal T, B, NK cell enumeration with flow cytometric analysis, abnormal in vivo T cell function studies with [hawaii.edu]

• Hypogammaglobulinemia

  Citation, DOI, disclosures and article data Citation: Weerakkody Y, Luong D, Sheikh Y, Primary hypogammaglobulinemia. [radiopaedia.org]

  Other names of the condition: Common Variable Hypogammaglobulinemia Common Variable Immune Deficiency Hypogammaglobulinemia, Acquired Immunodeficiency, Common Variable Immunoglobulin Deficiency, Late-Onset [xpertdox.com]

  Interestingly, autoimmunity can be the only clinical manifestation of CVID at the time of diagnosis and may even develop prior to hypogammaglobulinemia. [ucdavis.pure.elsevier.com]

  […] and certain disorders involving the immune mechanism D80-D89 - Certain disorders involving the immune mechanism D80 - Immunodeficiency with predominantly antibody defects D80.0 - Hereditary hypogammaglobulinemia D80.1 - Nonfamilial hypogammaglobulinemia [unboundmedicine.com]

  Clinical characteristics of patients with idiopathic primary hypogammaglobulinemia. [haematologica.org]

• Neutropenia

  Neutropenia is rare during CVID. The French DEFI study enrolled patients with primary hypogammaglobulinemia. Patients with CVID and neutropenia were retrospectively analyzed. [ncbi.nlm.nih.gov]

  Hematopoietic growth factors were used in 5 patients with neutropenia, and 2 patients received ongoing treatment with growth factors. [f1000research.com]

  Abnormal CBC findings may point out to a specific disease such as: 1) Lymphopenia (less than 2,000) in XLA, SCID, WAS, AT, DiGeorge, malnutrition and AIDS. 2) Neutropenia in hyper IgM syndrome, cyclic neutropenia, drug-induced neutropenia, Shwachman syndrome [hawaii.edu]

• Immunoglobulin A Decreased

  Diagnosis is based upon both serum immunoglobulin levels; decreased vaccine response; and exclusion of any other condition that could explain these inadequacies. [mastattack.org]

• Giardia Lamblia

  It is associated with immunodeficiency and infection, such as Giardia lamblia and Helicobacter pylori. [ncbi.nlm.nih.gov]

  Patients are also highly prone to Giardia lamblia infections and related gastrointestinal disorders, as well as to a variety of autoimmune diseases which appear in approximately 20% of them. [moh-it.pure.elsevier.com]

  Small bowel biopsy demonstrated lymphoid hyperplasia, a decreased number of plasma cells, and Giardia lamblia in the intestinal crypts. The serum carotene was decreased, and the seventy-two-hour stool fat was elevated. [pubs.rsna.org]

  The microorganisms that most frequently give rise to various infections are Haemophilus influenzae, Streptococcus pneumoniae, Staphylococcus aureus, Neisseria meningitidis, Pseudomonas aeruginosa and Giardia lamblia. [xpertdox.com]

• Lymphocytic Infiltrate

  Immunohistochemical typing of the lymphocytic infiltrate showed that B-cells were almost absent, matching the immunological profile of CVID. The case described is the first case reported in the literature of DPB in a patient affected by CVID. [ncbi.nlm.nih.gov]

  Some patients may suffer with lymphocytic infiltration of tissues, which can cause lymphadenopathy, splenomegaly and hepatomegaly, as well as the formation of granulomas. [xpertdox.com]

Ig replacement therapy (IV or SC) is the most successful and essential treatment plan for CVID. It hinders the recurrence of infections but does come at a certain financial cost.  
The levels that doctors wish to achieve in patients' blood are 400-500 mg/dL in adults; therefore, solutions of 3-12% IVIG can be used regularly. Common regimes stipulate that a dose of 400-600 mg/kg per month will achieve the expected result [6] [17]. Patients with permanent lung damage require greater amounts, 700-800 mg/dL. Doses are usually administered every 1-2 weeks (SC) or 3-4 weeks (IV).

Cyclosporin A has been administered to patients with lymphoid interstitial pneumonitis, which was caused by CVID; the outcome was extremely sucessful. Anti-CD20 monoclonal antibodies have been used against autoimmune thrombocytopenia and neutropenia. Sometimes surgery is bound to be a necessity: chronic sinusitis may be treated with endoscopic  surgery, autoimmune thrombocytopenia or hemolytic anemia can be treated with splenectomy.

Biopsy samples ensure that malignancy can be ruled out and an infection can be accurately diagnosed, should the lymph nodes be larger than expected. If an infection is diagnosed, antibiotics and IVIG are promptly administered. Furthermore, drugs like rituximab, TNF-α inhibitors (eg. infliximab), corticosteroids etc., can be used against autoimmune disorders, lymphoid interstitial pneumonia, and granuloma formation.

Male patients maintain a 20-year survival rate of 64% and female patients of 67%. The overall rate for male and female patients is 92% and 94%, respectively.

The prognosis depends on multiple factors: the existence of an acute autoimmune disease, periodic infections from which the patient sustains permanent lung damage and the emerge of cancer. Other factors that play a significant role in the estimation of the prognosis is the degree of organ damage and the extent to which a patient can successfully be protected against future infections. Lymphoid malignancy is a complication feared mostly in cases of polyclonal lymphocytic infiltration [6]. Increased serum IgM and diminished CD8 count may be indicative of polyclonal lymphocytic infiltration, as well as disorders of the autoimmune spectrum [6].

Despite tremendous effort, 40 years of research have yet to discover the exact primary cause for common variable immunodeficiency. This is partly because of the great diversity of this condition. Approximately 20% of patients suffering from CVID have a parent, sibling or offspring who also exhibits a selective IgA deficiency, leading to the suggestion that the disease may be affected by genetic factors. In cases where multiple family members are affected with CVID, about 5% of the patients display a coexisting IgA deficiency; it has been proposed that the inheritance pattern involved in these cases is that of an autosomal recessive inheritance.

Antirheumatic or antiepileptic medication has also been incriminated for causing CVID. If it is proven later on that such a drug has indeed caused the disorder, genetic factors are perceived as having played the role of predisposition, as opposed to causality.

A common flaw of the B-cell differentiation process is bound to play an important role in the occurrence of the disease, but in the majority of the patients the molecular defect remains unknown. Mutations are also sporadic in more than 90% of the cases. There has only been a sub-category of patients whose molecular abnormalities were identified: most are extremely uncommon, except for mutations in TNFRSF13B, which encodes the transmembrane activator and calcium modulator and cyclophilin ligand (TACI). Mutations in TACI occur in ∼8–10% of patients with CVID [3] [4]. 

From a clinical point of view, CVID resembles X-linked agammaglobulinemia concerning the types of infections that arise, but the former characteristically presents between the ages of 20 and 40, namely at a later stage when compared to X-linked agammaglobulinemia. A definite genetic cause of CVID has been established in less than 10% of the patients. The most common type of the condition involves patients who report no prior medical history of CVID in their family; in these cases it is believed that the disease is caused by a synergy of environmental and genetic factors (aka multifactorial inheritance), with genes controlling the differentiation and function of plasma cells being deemed as the primary cause.

Common variable immunodeficiency affects  approximately 1 person per 50,000 population throughout the world, without a definite tendency towards a specific race or gender.

It can occur in various ages, from infants to people  aged 40 years or older. Peaks of onset include children of 1-5 years and people of 16-20 years, with more than 2/3 of the patients having surpassed the 2nd decade of their lives when CVID is diagnosed [5]. It affects approximately 1 in 25,000–50,000 individuals [6] [7] [8], with report varying according to race. Given its relative prevalence and numbers of cases addressing a physician for medical help, CVID has an indubitable clinical significance [6] [9].

Patients suffering from CVID exhibit multiple immune-system defects; usually the predominant flaw concerns an impaired antibody production. Humoral and cell-mediated lymphocytic reactions are irregular; the basic pathophysiologic mechanism in CVID is a  failure in the process of B lymphocyte maturation. However, studies have shown that this type of abnormality is not frequently observed in patients. One study used pokeweed mitogen to stimulate B cells in vitro and proved that they did not posess the capability to differentiate into plasma cells, something that strongly suggests that surface molecules are expressed in B-cells in an abnormal way.
Cellular irregularities such as these are believed to be caused by defects of the second messenger and translocation pathways of B cells: defective protein kinase C activation and tyrosine phosphorylation. Further studies suggested that the complete lack of IgG and IgA, an increased rate of spontaneous apoptosis, insufficient DNA repair and somatic mutations all impair the functionality of B-cells.

Various factors and cofactors trigger the production of Ig from B cells acquired from patients with CVID: B-cell mitogens, soluble T-cell factors, specific B-cell differentiation factors, the Epstein-Barr virus, IL-2, IL-4 and IL-10. Among patients suffering from the condition, 25-30% also present with augmented levels of CD8+ T cells and a diminished CD4/CD8 ratio (less than 1). It is believed that increased cyclic adenosine monophosphate levels and the activation of protein kinase A constitute the cause for this phenomenon. Moreover, 60% of patients with CVID display a flawed reaction to T-cell receptor stimulation and expression of receptors for IL-2, IL-4, interleukin 5 (IL-5), and interferon gamma. CVID carrying an autosomal dominant inheritance pattern has been associated with the chromosome 4q [10], with one study supporting the validity of a certain gene, thought to be responsible for the development of autosomal dominant CVID/IgA deficiency. This gene's location is believed to be on chromosome 4q. Other potential locations for dominant CVID genes include chromosomes 5p and 16q.

There are not many preventive measures against CVID, since its causes still remain unknown. The only existing recommendation advises patients to receive a polysaccharide vaccine [18], because some of them are capable of producing sufficient antibodies, therefore rendering the immunization a success.

Common variable immunodeficiency is a condition otherwise known as acquired or adult-onset hypogammaglobulinemia. Its typical characteristic is insufficient immunoglobulin (Ig) levels in the plasma, accompanied by morphologically normal B cells that are able to multiply in number but exhibit an inability to turn into Ig-producing plasma cells, which is the last stage of their maturation process. Amongst the primary immunodeficiencies causing clinical manifestations, CVID is by far the most common and can include a broad range of symptoms and fluctuating degrees of severity. It is deemed as a group of conditions with no known cause, primarily due to the multiple immune system defects that have been found to cause this disorder. Low immunoglobulin levels result in a diminished ability to attack foreign substances (bacteria, viruses etc.) and protect the organism. Immunoglobulins are naturally produced by white blood B-type cells once they differentiate into plasma cells.

Common variable immunodeficiency features are decreased levels of most or all of the immunoglobulin classes (IgA, IgG, IgM, IgD, IgE). A diagnosis of CVID is based upon exclusion of other disorders causing immunodeficiency and is mainly established in cases of a B-cell dysfunction that cannot be traced to any other causes [1].

Lastly, CVID can present with a fluctuating clinical presentation and variable types of deficiency. Despite of decreased plasma concentration of immunoglobulin G (IgG) and immunoglobulin A (IgA) being typical of CVID, nearly 50% of patients with this disorder also exhibit low plasma levels of IgM and T-lymphocyte dysfunction. It has been estimated that about 20% of CVID patients will eventually be affected by an autoimmune disease [2].

People affected by common variable immunodeficiency have very low antibody levels and a normal number of B cells (lymphocytes). B cells follow a certain maturation pattern, and when they develop into the so-called plasma cells, they start producing antibodies. In cases of CVID, B cells fail to do so, resulting in less natural protection from microorganisms and other conditions.

Patients usually suffer from periodic infections, including pneumonia, sinusitis, diarrhea. Diarrhea in particular can also result from autoimmune causes; CVID patients are also at a greater risk of developing an autoimmune disease at a percentage of 25%. Antibiotics are administered in cases of infections and other types of treatment (corticosteroids, rituximab) are reserved for autoimmune phenomena.

Doctors suspect CVID by evaluating the symptomatology. Blood tests can measure antibody levels and observe how well the body responds to vaccines. Patients receive "supplementary antibodies" throughout their lives to compensate for those that cannot be naturally produced, namely sera containing antibodies of people with normally functioning immune systems. The majority of the patients have a normal life span, except for cases of a coexisting complication, such as a lymphoma which does not respond to treatment.

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