In terms of diagnosis for this condition, the following methods/tests are available:

- Endoscopic

- CT scan

- Serum endocrine autoantibody screen

- Histologic test

Immunosuppressive therapy may be used in "type I" of this condition, ketoconazole can be used for "autoimmune polyendocrine syndrome type I" under certain conditions The component diseases are managed as usual, the challenge is to detect the possibility of any of the syndromes, and to anticipate other manifestations. For example, in a person with known Type 2 autoimmune polyendocrine syndrome but no features of Addison's disease, regular screening for antibodies against 21-hydroxylase may prompt early intervention and hydrocortisone replacement to prevent characteristic crises

Diagnosis for "type 1" of this condition for example, sees that the following methods/tests are available:

- Endoscopic

- CT scan

- Histologic test

In terms of genetic testing, while it is done for "type 1" of this condition, "type 2" will only render (or identify) those genes which place the individual at higher risk. Other methods/exam to ascertain if an individual has autoimmune polyendocrine syndrome type 2 are:

- CT scan

- MRI

- Ultrasound

Management of autoimmune polyendocrine syndrome type 2 consists of the following:

Autoimmune polyendocrine syndrome type 1 treatment is based on the symptoms that are presented by the affected individual, additionally there is:

- Hormone replacement

- Systemic antifungal treatment

- Immunosuppressive treatment

Diagnosing SS is complicated by the range of symptoms a patient may manifest, and the similarity between symptoms of SS and those of other conditions. Also, patients who have symptoms of SS approach different specialities regarding their symptoms which make the diagnosis difficult. Since the symptoms of this autoimmune disorder such as dry eyes and dry mouth are very common among people, and mostly observed from the age of 40 and above, it is often mistaken as age-related, thus ignored. However, some medications can also cause symptoms that are similar to those of SS. The combination of several tests, which can be done in a series, can eventually lead to the diagnosis of SS.

SS is usually classified as either 'primary' or 'secondary'. Primary Sjögren syndrome occurs by itself and secondary Sjögren syndrome occurs when another connective tissue disease is present.

Blood tests can be done to determine if a patient has high levels of antibodies that are indicative of the condition, such as antinuclear antibody (ANA) and rheumatoid factor (because SS frequently occurs secondary to rheumatoid arthritis), which are associated with autoimmune diseases. Typical SS ANA patterns are SSA/Ro and SSB/La, of which Anti-SSB/La is far more specific; Anti-SSA/Ro is associated with numerous other autoimmune conditions, but are often present in SS. However, Anti-SSA and Anti-SSB tests are frequently not positive in SS.

The rose bengal test uses a stain that measures state and function of the lacrimal glands. This test involves placing the non-toxic dye rose bengal on the eyes. The dye’s distinctive colour helps in determining the state and functioning of tear film and the rate of tear evaporation. Any distinctive colour change observed will be indicative of SS, but many related diagnostic tools will be used to confirm the condition of SS.

Schirmer's test measures the production of tears: a strip of filter paper is held inside the lower eyelid for five minutes, and its wetness is then measured with a ruler. Producing less than of liquid is usually indicative of SS. This measurement analysis varies among people depending on other eye-related conditions and medications in use when the test is taken. A slit-lamp examination can reveal dryness on the surface of the eye.

Symptoms of dry mouth and dryness in the oral cavity are caused by the reduced production of saliva from the salivary glands (parotid gland, submandibular gland, and sublingual gland). To check the status of salivary glands and the production of saliva, a salivary flow-rate test is performed, in which the person is asked to spit as much as they can into a cup, and the resulting saliva sample is collected and weighed. This test's results can determine whether the salivary glands are functioning adequately. Not enough saliva produced could mean the person has SS. An alternative test is non-stimulated whole saliva flow collection, in which the person spits into a test tube every minute for 15 minutes. A resultant collection of less than is considered a positive result.

A lip/salivary gland biopsy takes a tissue sample that can reveal lymphocytes clustered around salivary glands, and damage to these glands due to inflammation. This test involves removing a sample of tissue from a person’s inner lip/salivary gland and examining it under a microscope. In addition, a sialogram, a special X-ray test, is performed to see if any blockage is present in the salivary gland ducts (i.e. parotid duct) and the amount of saliva that flows into the mouth.

Also, a radiological procedure is available as a reliable and accurate test for SS. A contrast agent is injected into the parotid duct, which opens from the cheek into the vestibule of the mouth opposite the neck of the upper second molar tooth. Histopathology studies should show focal lymphocytic sialadenitis. Objective evidence of salivary gland involvement is tested through ultrasound examinations, the level of unstimulated whole salivary flow, a parotid sialography or salivary scintigraphy, and autoantibodies against Ro (SSA) and/or La (SSB) antigens.

SS can be excluded from people with past head and neck radiation therapy, acquired immunodeficiency syndrome (AIDS), pre-existing lymphoma, sarcoidosis, graft-versus-host disease, and use of anticholinergic drugs.

Patient should seek a physician for skin tests. Typically, after a consultation with rheumatologist, the disease will be diagnosed. A dermatologist is also another specialist that can diagnose.

Blood studies and numerous other specialized tests depending upon which organs are affected.

Diagnosis of autoimmune disorders largely rests on accurate history and physical examination of the patient, and high index of suspicion against a backdrop of certain abnormalities in routine laboratory tests (example, elevated C-reactive protein). In several systemic disorders, serological assays which can detect specific autoantibodies can be employed. Localised disorders are best diagnosed by immunofluorescence of biopsy specimens. Autoantibodies are used to diagnose many autoimmune diseases. The levels of autoantibodies are measured to determine the progress of the disease.

There is no prevention mechanism for SS due to its complexity as an autoimmune disorder. However, lifestyle changes can reduce the risk factors of getting SS or reduce the severity of the condition with patients who have already been diagnosed. Diet is strongly associated with inflammation that is mostly seen in many autoimmune related diseases including SS. An experimental study concludes that SS patients show high sensitivity to gluten that directly relates to inflammation. Moderate exercise is also found to be helpful in SS patients mainly reducing the effect of lung inflammation.

The basic tests performed when an immunodeficiency is suspected should include a full blood count (including accurate lymphocyte and granulocyte counts) and immunoglobulin levels (the three most important types of antibodies: IgG, IgA and IgM).

Other tests are performed depending on the suspected disorder:

- Quantification of the different types of mononuclear cells in the blood (i.e. lymphocytes and monocytes): different groups of T lymphocytes (dependent on their cell surface markers, e.g. CD4+, CD8+, CD3+, TCRαβ and TCRγδ), groups of B lymphocytes (CD19, CD20, CD21 and Immunoglobulin), natural killer cells and monocytes (CD15+), as well as activation markers (HLA-DR, CD25, CD80 (B cells).

- Tests for T cell function: skin tests for delayed-type hypersensitivity, cell responses to mitogens and allogeneic cells, cytokine production by cells

- Tests for B cell function: antibodies to routine immunisations and commonly acquired infections, quantification of IgG subclasses

- Tests for phagocyte function: reduction of nitro blue tetrazolium chloride, assays of chemotaxis, bactericidal activity.

Due to the rarity of many primary immunodeficiencies, many of the above tests are highly specialised and tend to be performed in research laboratories.

Criteria for diagnosis were agreed in 1999. For instance, an antibody deficiency can be diagnosed in the presence of low immunoglobulins, recurrent infections and failure of the development of antibodies on exposure to antigens. The 1999 criteria also distinguish between "definitive", "probable" and "possible" in the diagnosis of primary immunodeficiency. "Definitive" diagnosis is made when it is likely that in 20 years, the patient has a >98% chance of the same diagnosis being made; this level of diagnosis is achievable with the detection of a genetic mutation or very specific circumstantial abnormalities. "Probable" diagnosis is made when no genetic diagnosis can be made, but the patient has all other characteristics of a particular disease; the chance of the same diagnosis being made 20 years later is estimated to be 85-97%. Finally, a "possible" diagnosis is made when the patient has only some of the characteristics of a disease are present, but not all.

Patients show markedly low immunoglobulin levels of IgG, IgA, and IgM.

AGID is diagnosed with a complete medical history, exam of patients motility and with special blood tests looking for autoantibodies consistent with neurologic autoimmunity. Blood tests included evaluations of immunofluorescence (neuronal nuclear and cytoplasmic antibodies), radioimmunoprecipitation assays (neuronal and muscle plasma membrane cation channel antibodies), and enzyme-linked immunosorbent assay (muscle striational antibodies). A finding, along with medical history, of ganglionic neuronal acetylcholine receptor and N-type voltage-gated calcium channel autoantibodies in the blood stream would result in a medically acceptable diagnosis of AGID.

When suspected, the diagnosis can be confirmed by laboratory measurement of IgA level in the blood. SigAD is an IgA level < 7 mg/dL with normal IgG and IgM levels (reference range 70–400 mg/dl for adults; children somewhat less).

There is a diagnostic test for AIE that looks for an antibody against the enterocyte. The diagnostic test contains the Western Blot which can identify the antibody IgG or IgA and with the immunohistochemistry can localize these antibodies. Endoscopy with biopsies of the colon, small colon, stomach, and other locations may be helpful in diagnosing. This test is done to look at the stomach and small intestines and to see what cells are infiltrating the digestive tract. There are also documented cases of autoimmune enteropathy where the auto-antibodies were undetectable and the diagnosis was made on the basis of clinical presentation and response to treatment.

Pyridostigmine is a pharmaceutical treatment option for patients with AGID.

In severe cases patients with AGID are required to abandon eating foods, requiring them to get nourishment through a process called Parenteral nutrition, where the patient is fed via a permanent IV and the liquid nourishment is infused directly in the blood stream, as opposed to a feeding tube.

Prognosis is excellent, although there is an association with autoimmune disease. Of note, selective IgA deficiency can complicate the diagnosis of one such condition, celiac disease, as the deficiency masks the high levels of certain IgA antibodies usually seen in celiac disease.

As opposed to the related condition CVID, selective IgA deficiency is not associated with an increased risk of cancer.

Patients with Selective IgA deficiency are at risk of anaphylaxis from blood transfusions. These patients should receive IgA free containing blood products and ideally blood from IgA-deficient donors.

Vitamin D/Sunlight

Omega-3 Fatty Acids

Probiotics/Microflora

Antioxidants

Computed tomography (CT) findings in AIP include a "diffusely enlarged hypodense" pancreas or a focal mass that may be mistaken for a pancreatic malignancy. A low-density, "capsule-like rim on CT" (possibly corresponding to an inflammatory process involving peripancreatic tissues) is thought to be an additional characteristic feature (thus the mnemonic: "sausage-shaped"). Magnetic resonance imaging (MRI) reveals a diffusely decreased signal intensity and delayed enhancement on dynamic scanning. The characteristic ERCP finding is segmental or diffuse irregular narrowing of the main pancreatic duct, usually accompanied by an extrinsic-appearing stricture of the distal bile duct. Changes in the extrapancreatic bile duct similar to those of primary sclerosing cholangitis (PSC) have been reported.

The role of endoscopic ultrasound (EUS) and EUS-guided fine-needle aspiration (EUS-FNA) in the diagnosis of AIP is not well described, and EUS findings have been described in only a small number of patients. In one study, EUS revealed a diffusely swollen and hypoechoic pancreas in 8 of the 14 (57%) patients, and a solitary, focal, irregular mass was observed in 6 (46%) patients. Whereas EUS-FNA is sensitive and specific for the diagnosis of pancreatic malignancy, its role in the diagnosis of AIP remains unclear.

Most recently the fourteenth Congress of the International Association of Pancreatology developed the International Consensus Diagnostic Criteria (ICDC) for AIP. The ICDC emphasizes five cardinal features of AIP which includes the imaging appearance of pancreatic parenchyma and the pancreatic duct, serum IgG4 level, other organ involvement with IgG4-related disease, pancreatic histology and response to steroid therapy.

In 2002, the Japanese Pancreas Society proposed the following diagnostic criteria for autoimmune pancreatitis:

For diagnosis, criterion I (pancreatic imaging) must be present with criterion II (laboratory data) and/or III (histopathologic findings).

Mayo Clinic has come up with five diagnostic criteria called HISORt criteria which stands for histology, imaging, serology, other organ involvement, and response to steroid therapy.

The life span in patients with Schnitzler syndrome has not been shown to differ much from the general population. Careful follow-up is advised, however. A significant proportion of patients develops a lymphoproliferative disorder as a complication, most commonly Waldenström's macroglobulinemia. This may lead to symptoms of hyperviscosity syndrome. AA amyloidosis has also been reported in people with Schnitzler syndrome.

There is no current cure. The only way to treat this disease is by treating symptoms. Commonly patients are prescribed immunosuppressive drugs. Another route would be to take collagen regulation drugs.

Autoimmune polyendocrine syndromes (APS) occur when more than one autoimmune disease occurs in endocrine glands. These syndromes are also called Polyendocrine Autoimmune Disorders. In Type 3, autoimmune thyroiditis and another endocrine autoimmune disease are present, but the adrenal cortex is not involved.

A survey of 10,000 American households revealed that the prevalence of diagnosed primary immunodeficiency approaches 1 in 1200. This figure does not take into account people with mild immune system defects who have not received a formal diagnosis.

Milder forms of primary immunodeficiency, such as selective immunoglobulin A deficiency, are fairly common, with random groups of people (such as otherwise healthy blood donors) having a rate of 1:600. Other disorders are distinctly more uncommon, with incidences between 1:100,000 and 1:2,000,000 being reported.

Adenocarcinoma of the bowel has been associated with coeliac disease.