Immunosuppressive therapies, encompassing corticosteroids, azathioprine, methotrexate and more recently, rituximab, are the mainstay of therapy. Other treatments include PE, IVIG, and thymectomy. Patients reportedly exhibited a heterogenous response to immunomodulation.

Antiepileptics can be used for symptomatic relief of peripheral nerve hyperexcitability. Indeed, some patients have exhibited a spontaneous remission of symptoms.

The administration of immunotherapy, in association with chemotherapy or tumor removal, .

Familial dysautonomia is inherited in an autosomal recessive pattern, which means 2 copies of the gene in each cell are altered. If both parents are shown to be carriers by genetic testing, there is a 25% chance that the child will produce FD. Prenatal diagnosis for pregnancies at increased risk for FD by amniocentesis (for 14–17 weeks) or chorionic villus sampling (for 10–11 weeks) is possible.

AQP4-Ab-negative NMO presents problems for diagnosis. The behavior of the oligoclonal bands respect MS can help to establish a more accurate diagnosis. Oligoclonal bands in NMO are rare and they tend to disappear after the attacks, while in MS they are nearly always present and persistent.

It is important to notice for differential diagnosis that, though uncommon, it is possible to have longitudinal lesions in MS

Other problem for diagnosis is that AQP4ab in MOGab levels can be too low to be detected. Some additional biomarkers have been proposed.

The current gold standard diagnostic test for EE is intestinal biopsy and histological analysis. Histological changes observed include:

- Villous blunting

- Crypt hypertrophy

- Villous fusion

- Mucosal inflammation

However, this procedure is considered too invasive, complex and expensive to be implemented as standard of care. As a result, there are various research efforts underway to identify biomarkers associated with EE, which could serve as less invasive, yet representative, tools to screen for and identify EE from stool samples.

In an effort to identify simple, accurate diagnostic tests for EE, the Bill and Melinda Gates Foundation (BMGF) has established an EE biomarkers consortium as part of their Global Grand Challenges initiative (specifically, the Discover Biomarkers of Gut Function challenge).

So far, various biomarkers have been selected and studied based on the current understanding of EE pathophysiology:

- Gut permeability/barrier function

- Dual sugar permeability (lactose-to-mannitol ratio)

- Intestinal inflammation

- Alpha-1 anti-trypsin

- Neopterin

- Myeloperoxidase

- Exocrine (hormonal) markers

- Bacterial translocation markers

- Endotoxin core antibody

- Markers of systemic inflammation

- Alpha-1 glycoprotein

- C-reactive protein (CRP)

It is postulated that the limited of understanding of EE is partially due to the paucity of reliable biomarkers, making it difficult for researchers to track the epidemiology of the condition and assess the efficacy of interventions.

There are multiple large-field, multi-country research initiatives focusing on strategies to prevent and treat EE.

- The MAL-ED project

- The Alive and Thrive nutrition project

- The Sanitation, Hygiene and Infant Nutrition Efficacy (SHINE) Trial (ClinicalTrials.gov identifier: NCT01824940)

- The WASH Benefits Study

Genetic testing is performed on a small sample of blood from the tested individual. The DNA is examined with a designed probe specific to the known mutations. The accuracy of the test is above 99%. Dr. Anat Blumenfeld of the Hadasah Medical center in Jerusalem identified chromosome number 9 as the responsible chromosome.

The Mayo Clinic proposed a revised set of criteria for diagnosis of Devic's disease in 2006. Those new guidelines require two absolute criteria plus at least two of three supportive criteria. In 2015 a new review was published by an international panel refining the previous clinical case definition but leaving the main criteria unmodified:

Absolute criteria:

1. Optic neuritis

2. Acute myelitis

Supportive criteria:

1. Brain MRI not meeting criteria for MS at disease onset

2. Spinal cord MRI with continuous T2-weighted signal abnormality extending over three or more vertebral segments, indicating a relatively large lesion in the spinal cord

3. NMO-IgG seropositive status (The NMO-IgG test checks the existence of antibodies against the aquaporin 4 antigen.)

aHUS can be inherited or acquired, and does not appear to vary by race, gender, or geographic area. As expected with an ultra-rare disease, data on the prevalence of aHUS are extremely limited. A pediatric prevalence of 3.3 cases per million population is documented in one publication of a European hemolytic uremic syndrome (HUS) registry involving 167 pediatric patients.

A diagnosis can only be definitively made after genetic testing to look for a mutation in the "DOCK8" gene. However, it can be suspected with a high IgE level and eosinophilia. Other suggestive laboratory findings include decreased numbers of B cells, T cells, and NK cells; and hypergammaglobulinemia. It can be distinguished from autosomal dominant hyper-IgE (STAT3 deficiency) because people with DOCK8 deficiency have low levels of IgM and an impaired secondary immune response. IgG and IgA levels are usually normal to high. It can be distinguished from the similar X-linked Wiskott–Aldrich syndrome by the presence of thrombocytopenia and the consequent bloody diarrhea, as well as its pattern of inheritance. WHIM syndrome, caused by a mutation in CXCR4, is associated with similar chronic cutaneous viral infections.

aHUS is not the only condition that causes systemic TMA, a fact that makes differential diagnosis essential. Historically, the clinical diagnosis of TMA-causing diseases was grouped into a broad category that (in addition to aHUS) included thrombotic thrombocytopenic purpura (TTP) and Shiga-toxin-producing Escherichia coli hemolytic uremic syndrome (STEC-HUS). However, it is now understood that although aHUS, STEC-HUS, and TTP have similar clinical presentations, they have distinct causes and specific tests can be conducted to differentiate these diseases. In addition, there are other conditions that can cause TMA as a secondary manifestation; these entities include systemic lupus erythematosus (SLE), malignant hypertension, progressive systemic sclerosis (PSS, also known as scleroderma), the pregnancy-associated HELLP (hemolysis, liver dysfunction, and low platelets) syndrome, and toxic drug reaction (e.g., to cocaine, cyclosporine, or tacrolimus). Nevertheless, aHUS should be suspected in patients presenting with systemic TMA, and appropriate diagnostic work-up should be undertaken.

The neurological and kidney-related signs and symptoms of aHUS overlap with those of TTP. However, unlike aHUS, TTP is primarily an autoimmune disorder in which the presence of an inhibitory autoantibody results in severe deficiency of ADAMTS13, an enzyme that cleaves von Willebrand factor (vWf), a large protein involved in blood clotting, into smaller pieces. (TTP also can be a genetic disorder characterized by mutations in the ADAMTS13 gene leading to severe ADAMTS13 deficiency. This congenital cause of ADAMTS13 deficiency is called Upshaw-Schülman syndrome.) A lab test showing ADAMTS13 activity levels of ≤5% is indicative of TTP.

Similarly, the gastrointestinal (GI) signs and symptoms of aHUS overlap with those of STEC-HUS. Stool samples from patients with diarrhea or other GI symptoms should be tested for STEC and the presence of Shiga-toxin. However, a positive identification of Shiga-toxin, which is required to diagnose STEC-HUS, does not rule out aHUS. Nevertheless, in the appropriate clinical setting, a positive identification of Shiga-toxin makes aHUS very unlikely.

While sick building syndrome (SBS) encompasses a multitude of non-specific symptoms, building-related illness (BRI) comprises specific, diagnosable symptoms caused by certain agents (chemicals, bacteria, fungi, etc.). These can typically be identified, measured, and quantified. There are usually 4 causal agents in BRI; 1.) Immunologic, 2.) Infectious, 3.) toxic, and 4.) irritant. For instance, Legionnaire's disease, usually caused by "Legionella pneumophila", involves a specific organism which could be ascertained through clinical findings as the source of contamination within a building. SBS does not have any known cure; alleviation consists of removing the affected person from the building associated with non-specific symptoms. BRI, on the other hand, utilizes treatment appropriate for the contaminant identified within the building (e.g., antibiotics for Legionnaire's disease). In most cases, simply improving the indoor air quality (IAQ) of a particular building will attenuate, or even eliminate, the acute symptoms of SBS, while removal of the source contaminant would prove more effective for a specific illness, as in the case of BRI. Building-Related Illness is vital to the overall understanding of Sick Building Syndrome because BRI illustrates a causal path to infection, theoretically. Office BRI may more likely than not be explained by three events: “Wide range in the threshold of response in any population (susceptibility), a spectrum of response to any given agent, or variability in exposure within large office buildings." Isolating any one of the three aspects of office BRI can be a great challenge, which is why those who find themselves with BRI should take three steps, history, examinations, and interventions. History describes the action of continually monitoring and recording the health of workers experiencing BRI, as well as obtaining records of previous building alterations or related activity. Examinations go hand in hand with monitoring employee health. This step is done by physically examining the entire workspace and evaluating possible threats to health status among employees. Interventions follow accordingly based off the results of the Examination and History report.

There is no single test that can fully diagnose fibromyalgia and there is debate over what should be considered essential diagnostic criteria and whether an objective diagnosis is possible. In most cases, people with fibromyalgia symptoms may also have laboratory test results that appear normal and many of their symptoms may mimic those of other rheumatic conditions such as arthritis or osteoporosis. The most widely accepted set of classification criteria for research purposes was elaborated in 1990 by the Multicenter Criteria Committee of the American College of Rheumatology. These criteria, which are known informally as "the ACR 1990", define fibromyalgia according to the presence of the following criteria:

- A history of widespread pain lasting more than three months – affecting all four quadrants of the body, i.e., both sides, and above and below the waist.

- Tender points – there are 18 designated possible tender points (although a person with the disorder may feel pain in other areas as well). Diagnosis is no longer based on the number of tender points.

The ACR criteria for the classification of patients were originally established as inclusion criteria for research purposes and were not intended for clinical diagnosis but have now become the "de facto" diagnostic criteria in the clinical setting. It should be noted that the number of tender points that may be active at any one time may vary with time and circumstance. A controversial study was done by a legal team looking to prove their client's disability based primarily on tender points and their widespread presence in non-litigious communities prompted the lead author of the ACR criteria to question now the useful validity of tender points in diagnosis. Use of control points has been used to cast doubt on whether a person has fibromyalgia, and to claim the person is malingering; however, no research has been done for the use of control points to diagnose fibromyalgia, and such diagnostic tests have been advised against, and people complaining of pain all over should still have fibromyalgia considered as a diagnosis.

Children with DOCK8 deficiency do not tend to live long; sepsis is a common cause of death at a young age. CNS and vascular complications are other common causes of death.

In 2010, the American College of Rheumatology approved provisional revised diagnostic criteria for fibromyalgia that eliminated the 1990 criteria's reliance on tender point testing. The revised criteria use a widespread pain index (WPI) and symptom severity scale (SS) in place of tender point testing under the 1990 criteria. The WPI counts up to 19 general body areas in which the person has experienced pain in the preceding two weeks. The SS rates the severity of the person's fatigue, unrefreshed waking, cognitive symptoms, and general somatic symptoms, each on a scale from 0 to 3, for a composite score ranging from 0 to 12. The revised criteria for diagnosis are:

- WPI ≥ 7 and SS ≥ 5 "OR" WPI 3–6 and SS ≥ 9,

- Symptoms have been present at a similar level for at least three months, "and"

- No other diagnosable disorder otherwise explains the pain.

Prenatal stress and negative mood during pregnancy has been shown to increase the risk for poor childbirth outcomes and postnatal maternal mood problems. Additionally, prenatal distress can interfere with the mother-infant attachment and child development outcomes. Despite the clear association between prenatal stress and child outcomes, frequently women do not receive screening, prevention, or treatment for mood or stress concerns.

Given the relationship between prenatal stress and child outcomes, it is essential to examine interventions that aim to reduce anxiety, depression, and stress during pregnancy. Mindfulness based stress reduction has been demonstrated to reduce anxiety and depression for people with stress-related and chronic medical conditions.

One pilot study shows promise for the potential of a mindfulness-based intervention to reduce negative affect and anxiety of women during pregnancy. Based out of the California Pacific Medical Center Research Institute, investigators Dr. Cassandra Vieten and Dr. John Astin conducted a wait-list control pilot study that tested a group-based mindfulness intervention. There were 31 women enrolled in the study: 13 women were assigned to the intervention and 18 women were assigned to the control group. Measures of anxiety, negative affect, positive affect, depression, mindfulness, perceived stress, and affect regulation were taken before intervention or control was assigned and after the intervention or control was completed. Measures were repeated at a follow-up visit 3 months after the intervention or control was completed. The investigators found a significant decrease in anxiety (p<.05) and negative affect (p <.04) in women who completed the mindfulness based intervention, but not a significant decrease in depression, positive affect, mindfulness, affect regulation, and perceived stress. These results suggest that mindfulness intervention during pregnancy reduce anxiety and negative affect of mothers. This study is a promising start to the potential impact that mindfulness based interventions could have on reducing prenatal stress, and thereby improving child outcomes.

Clinical evaluation and identification of characteristics papules may allow a dermatologist to diagnose Degos disease. The papules have a white center and are bordered with a red ring. After lesions begin to appear, the diagnosis for Degos disease can be supported by histological findings. Most cases will show a wedge-shaped connective tissue necoris in the deep corium. This shape is due to the blockage/occlusion of small arteries.

Individuals may be diagnosed with the benign form if only the papules are present. However, an individual may be diagnosed with the malignant form if involvement of other organs like the lungs, intestine and/or central nervous system occurs. The malignant, or systematic form of this condition may suddenly develop even after having papules present for several years. In order to quickly diagnose this shift to the malignant variant of the disease, it is important for individuals to have consistent follow-up evaluations.In these evaluations, depending on which organs are suspected to be involved, the following procedures and tests may be conducted: skin inspection, brain magnetic resonance tomography, colonoscopy, chest X-ray, and/or abdominal ultrasound.

An estimated 64 percent of patients with venous thromboembolism may have activated protein C resistance.

Prenatal stress (or prenatal maternal stress) is exposure of an expectant mother to stress, which can be caused by stressful life events or by environmental hardships. The resulting changes to the mother's hormonal and immune system may harm the fetus's (and after birth, the infant's) immune function and brain development.

Prenatal stress is shown to have several affects in fetal brain development. In the hippocampus of adult male rats, prenatal stress has shown to decrease the rate of proliferation and cell death in the hypothalamus-pituitary axis. Prenatal stressed animals have prolonged corticosterone response. Removing the adrenal glands of the mother eliminates the effect of the pup's corticosterone response. Supplementing the adrenalectamized mother with corticosterone, rescued the hypothalamic-pituitary-axis response to maternal stress for prenatally stressed offspring. Prenatal stress caused high glucocorticoids, which in turn affects the hypothalamic-pituitary-axis negative feedback.

A study by García-Cáceres et al. showed that prenatal stress decreases cell turnover and proliferation in the hypothalamus of adult rats, which reduces structural plasticity and reduces the response to stress in adulthood. This study also showed that when prenatally stressed rats were stressed in adulthood the females showed an increase in corticotropin-releasing hormone suggesting it to be an up-regulation in the hypothalamic-pituitary adrenal axis. Males showed no elevation of corticosterone levels. Increase in adrenocorticotropic hormone with no effect of adult stress and a decrease in the corticotropin-releasing hormone mRNA in the hypothalamus showed a down-regulation. The author concludes that this makes prenatally stressed females less reactive to later life stressors than males.

The diagnosis is usually suspected following a CT scan. Typical features on CT include solid and sub-solid nodules, ground glass change and reticulation. There may be features of multi-system involvement such as adenopathy and splenomegaly.

The commonest abnormality on lung function testing is a decrease in gas transfer. Both obstructive and restrictive patterns on spirometry have been reported.

The differential diagnosis includes infection, other interstitial lung diseases and malignant disease including lymphoma. Exclusion of infection is therefore an important step in management, but confirmation of the diagnosis requires lung biopsy. In people who have lung disease prior to a diagnosis of CVID, the differential diagnosis includes sarcoidosis. Sarcoid is also characterised by granulomatous involvement of the lung and therefore patients being investigated for sarcoid should have serum immunoglobulins measured to exclude CVID.

The similarities between HUS, aHUS, and TTP make differential diagnosis essential. All three of these systemic TMA-causing diseases are characterized by thrombocytopenia and microangiopathic hemolysis, plus one or more of the following: neurological symptoms (e.g., confusion, cerebral convulsions, seizures); renal impairment (e.g., elevated creatinine, decreased estimated glomerular filtration rate [eGFR], abnormal urinalysis); and gastrointestinal (GI) symptoms (e.g., diarrhea, nausea/vomiting, abdominal pain, gastroenteritis).The presence of diarrhea does not exclude aHUS as the cause of TMA, as 28% of patients with aHUS present with diarrhea and/or gastroenteritis. First diagnosis of aHUS is often made in the context of an initial, complement-triggering infection, and Shiga-toxin has also been implicated as a trigger that identifies patients with aHUS. Additionally, in one study, mutations of genes encoding several complement regulatory proteins were detected in 8 of 36 (22%) patients diagnosed with STEC-HUS. However, the absence of an identified complement regulatory gene mutation does not preclude aHUS as the cause of the TMA, as approximately 50% of patients with aHUS lack an identifiable mutation in complement regulatory genes.

Diagnostic work-up supports the differential diagnosis of TMA-causing diseases. A positive Shiga-toxin/EHEC test confirms a cause for STEC-HUS, and severe ADAMTS13 deficiency (i.e., ≤5% of normal ADAMTS13 levels) confirms a diagnosis of TTP.

The papules characteristic for this disease develop due to infractions, or blockages in small-medium arteries and veins. The underlying cause is unknown for this disease. Though not confirmed, some cases have shown signs of inheritance between first-degree relatives. It has been suggested that the disease has a familial inheritance pattern; it is thought to be an autosomal dominant disorder. In most cases of familial inheritance, the benign variant of the disease has been present.

Due to the lack of knowledge of the pathomechanism for this condition prevention strategies are not known. However, in order to prevent worsening of symptoms, consistent evaluations should be conducted by a physician.

Activated protein C resistance (APCR) is a hemostatic disorder characterized by a poor anticoagulant response to activated protein C (APC). This results in an increased risk of venous thrombosis, which can cause problems with circulation, such as pulmonary embolism.

The disorder can be acquired or inherited, the hereditary form having an autosomal dominant inheritance pattern.

Some studies have shown a small difference between genders, with women having slightly higher reports of SBS symptoms compared to men. However, many other studies have shown an even higher difference in the report of sick building syndrome symptoms in women compared to men. It is not entirely clear, however, if this is due to biological, social, or occupational factors.

A 2001 study published in the Journal Indoor Air 2001 gathered 1464 office-working participants to increase the scientific understanding of gender differences under the Sick Building Syndrome phenomenon. Using questionnaires, ergonomic investigations, building evaluations, as well as physical, biological, and chemical variables, the investigators obtained results that compare with past studies of SBS and gender. The study team found that across most test variables, prevalence rates were different in most areas, but there was also a deep stratification of working conditions between genders as well. For example, men’s workplace tend to be significantly larger and have all around better job characteristics. Secondly, there was a noticeable difference in reporting rates, finding that women have higher rates of reporting roughly 20% higher than men. This information was similar to that found in previous studies, indicating a potential difference in willingness to report.

There might be a gender difference in reporting rates of sick building syndrome because women tend to report more symptoms than men do. Along with this, some studies have found that women have a more responsive immune system and are more prone to mucosal dryness and facial erythema. Also, women are alleged by some to be more exposed to indoor environmental factors because they have a greater tendency to have clerical jobs, wherein they are exposed to unique office equipment and materials (example: blueprint machines), whereas men often have jobs based outside of offices.

Morbidity and mortality range from both extremes as the significance correlate with the underlying systemic disease.