In secondary cases, treatment of the cause, where possible, is indicated. Additionally, treatment for HLH itself is usually required.

While optimal treatment of HLH is still being debated, current treatment regimes usually involve high dose corticosteroids, etoposide and cyclosporin. Intravenous immunoglobulin is also used. Methotrexate and vincristine have also been used. Other medications include cytokine targeted therapy.

An experimental treatment, an anti IFN-gamma monoclonal antibody tentatively named NI-0501, is in clinical trials for treating primary HLH. The FDA awarded breakthrough drug status to NI-0501 in 2016.

The treatment of primary immunodeficiencies depends foremost on the nature of the abnormality. Somatic treatment of primarily genetic defects is in its infancy. Most treatment is therefore passive and palliative, and falls into two modalities: managing infections and boosting the immune system.

Reduction of exposure to pathogens may be recommended, and in many situations prophylactic antibiotics or antivirals may be advised.

In the case of humoral immune deficiency, immunoglobulin replacement therapy in the form of intravenous immunoglobulin (IVIG) or subcutaneous immunoglobulin (SCIG) may be available.

In cases of autoimmune disorders, immunosuppression therapies like corticosteroids may be prescribed.

Bone marrow transplant may be possible for Severe Combined Immune Deficiency and other severe immunodeficiences.

Virus-specific T-Lymphocytes (VST) therapy is used for patients who have received hematopoietic stem cell transplantation that has proven to be unsuccessful. It is a treatment that has been effective in preventing and treating viral infections after HSCT. VST therapy uses active donor T-cells that are isolated from alloreactive T-cells which have proven immunity against one or more viruses. Such donor T-cells often cause acute graft-versus-host disease (GVHD), a subject of ongoing investigation. VSTs have been produced primarily by ex-vivo cultures and by the expansion of T-lymphocytes after stimulation with viral antigens. This is carried out by using donor-derived antigen-presenting cells. These new methods have reduced culture time to 10–12 days by using specific cytokines from adult donors or virus-naive cord blood. This treatment is far quicker and with a substantially higher success rate than the 3–6 months it takes to carry out HSCT on a patient diagnosed with a primary immunodeficiency. T-lymphocyte therapies are still in the experimental stage; few are even in clinical trials, none have been FDA approved, and availability in clinical practice may be years or even a decade or more away.

Available treatment falls into two modalities: treating infections and boosting the immune system.

Prevention of Pneumocystis pneumonia using trimethoprim/sulfamethoxazole is useful in those who are immunocompromised. In the early 1950s Immunoglobulin(Ig) was used by doctors to treat patients with primary immunodeficiency through intramuscular injection. Ig replacement therapy are infusions that can be either subcutaneous or intravenously administrated, resulting in higher Ig levels for about three to four weeks, although this varies with each patient.

Several medications have been studied for the treatment of TNF receptor associated periodic syndrome including etanercept, and infliximab,

The prognosis is guarded with an overall mortality of 50%. Poor prognostic factors included HLH associated with malignancy, with half the patients dying by 1.4 months compared to 22.8 months for non-tumour associated HLH patients.

Secondary HLH in some individuals may be self-limited because patients are able to fully recover after having received only supportive medical treatment (i.e., IV immunoglobulin only). However, long-term remission without the use of cytotoxic and immune-suppressive therapies is unlikely in the majority of adults with HLH and in those with involvement of the central nervous system (brain and/or spinal cord).

In terms of treatment for TNF receptor associated periodic syndrome, corticosteroids can be administered for the reduction of the severity of this condition, NSAIDS may be used for fever.

There is no known cure at the moment but there are several things that can be done to relieve the symptoms. Moisturising products are very helpful to minimize the scaling/cracking, and anti-infective treatments are useful when appropriate because the skin is very susceptible to infection. Extra protein in the diet during childhood is also beneficial, to replace that which is lost through the previously mentioned "leaky" skin.

Steroid and retinoid products have been proven ineffective against Netherton syndrome, and may in fact make things worse for the affected individual.

Intravenous immunoglobulin has become established as the treatment of choice in Netherton's syndrome. This therapy reduces infection; enables improvement and even resolution of the skin and hair abnormalities, and dramatically improves quality of life of the patients; although exactly how it achieves this is not known. Given this; it is possible that the reason Netherton's usually is not very severe at or shortly after birth is due to a protective effect of maternal antibodies; which cross the placenta but wane by four to six months.

The best treatment for MAS has not been firmly established. Most commonly used treatments include high-dose glucocorticoids, and cyclosporine. In refractory cases treatment regimens are used similar to that in HLH.

Systemic corticosteroids such as (prednisone) can produce rapid improvement and are the “gold standard” for treatment. The temperature, white blood cell count, and eruption improve within 72 hours. The skin lesions clear within 3 to 9 days. Abnormal laboratory values rapidly return to normal. There are, however, frequent recurrences. Corticosteroids are tapered within 2 to 6 weeks to zero.

Resolution of the eruption is occasionally followed by milia and scarring. The disease clears spontaneously in some patients. Topical and/or intralesional corticosteroids may be effective as either monotherapy or adjuvant therapy.

Oral potassium iodide or colchicine may induce rapid resolution.

Patients who have a potential systemic infection or in whom corticosteroids are contraindicated can use these agents as a first-line therapy.

In one study, indomethacin, 150 mg per day, was given for the first week, and 100 mg per day was given for 2 additional weeks. Seventeen of 18 patients had a good initial response; fever and arthralgias were markedly attenuated within 48 hours, and eruptions cleared between 7 and 14 days.

Patients whose cutaneous lesions continued to develop were successfully treated with prednisone (1 mg/kg per day). No patient had a relapse after discontinuation of indomethacin.

Other alternatives to corticosteroid treatment include dapsone, doxycycline, clofazimine, and cyclosporine. All of these drugs influence migration and other functions of neutrophils.

Prognosis depends greatly on the nature and severity of the condition. Some deficiencies cause early mortality (before age one), others with or even without treatment are lifelong conditions that cause little mortality or morbidity. Newer stem cell transplant technologies may lead to gene based treatments of

debilitating and fatal genetic immune deficiencies. Prognosis of acquired immune deficiencies depends on avoiding or treating the causative agent or

condition (like AIDS).

There are many lymphoproliferative disorders that are associated with organ transplantation and immunosuppressant therapies. In most reported cases, these cause B cell lymphoproliferative disorders; however, some T cell variations have been described. The T cell variations are usually caused by the prolonged use of T cell suppressant drugs, such as sirolimus, tacrolimus, or ciclosporin.

Currently Aggressive NK-cell leukemia, being a subtype of PTCL, is treated similarly to B-cell lymphomas. However, in recent years, scientists have developed techniques to better recognize the different types of lymphomas, such as PTCL. It is now understood that PTCL behaves differently from B-cell lymphomas and therapies are being developed that specifically target these types of lymphoma. Currently, however, there are no therapies approved by the U.S. Food and Drug Administration (FDA) specifically for PTCL. Anthracycline-containing chemotherapy regimens are commonly offered as the initial therapy. Some patients may receive a stem cell transplant. Novel approaches to the treatment of PTCL in the relapsed or refractory setting are under investigation.

There is as yet inadeqaute data from randomised controlled trials.

Treatment with HAART and ACE inhibitors/Angiotensin receptor blockers has been shown to be beneficial and should be given to all patients unless otherwise contra-indicated. General renoprotective measures and the treatment of the complications of nephrotic syndrome and kidney failure are adjunctive.

Corticosteroid treatment can be useful in patients who do not respond to the above treatment. There is some evidence that ciclosporin might be helpful in selective cases, however further trials are required on both steroids and ciclosporin before these drugs can become standardised treatment if at all.

Antiviral treatment has been tried with some success in a small number of patients.

Treatment with chemotherapy has been used with some success, particularly using lomustine, prednisone, doxorubicin, and cyclophosphamide. Because of the rapid progression of this aggressive disease, the prognosis is very poor.

Plasmapheresis and intravenous immunoglobulins (IVIG) are the two main immunotherapy treatments for GBS. Plasmapheresis attempts to reduce the body's attack on the nervous system by filtering antibodies out of the bloodstream. Similarly, administration of IVIG neutralizes harmful antibodies and inflammation. These two treatments are equally effective, but a combination of the two is not significantly better than either alone. Plasmapheresis speeds recovery when used within four weeks of the onset of symptoms. IVIG works as well as plasmapheresis when started within two weeks of the onset of symptoms, and has fewer complications. IVIG is usually used first because of its ease of administration and safety. Its use is not without risk; occasionally it causes liver inflammation, or in rare cases, kidney failure. Glucocorticoids alone have not been found to be effective in speeding recovery and could potentially delay recovery.

For more severe disease, oral corticosteroids may be necessary to reduce the inflammatory response. When large amounts of steroids are required or if the disease is severe and is not responding to steroid therapy, other immunosuppressive medications often are recommended. These immunosuppressive drugs include methotrexate, cyclophosphamide, cyclosporine or azathioprine. In some cases, combinations of these medicines are prescribed. Occasionally, if the disease has damaged blood vessels, cochlear implantation may

need to be done to correct the problem.

Cinnarizine is mainly used to treat nausea and vomiting associated with motion sickness, vertigo, Ménière's disease, or Cogan's syndrome. Studies have shown it to produce significant improvement in hearing loss in some patients.

Following the acute phase, around 40% of people require intensive rehabilitation with the help of a multidisciplinary team to focus on improving activities of daily living (ADLs). Studies into the subject have been limited, but it is likely that intensive rehabilitation improves long-term symptoms. Teams may include physical therapists, occupational therapists, speech language pathologists, social workers, psychologists, other allied health professionals and nurses. The team usually works under the supervision of a neurologist or rehabilitation physician directing treatment goals.

Physiotherapy interventions include strength, endurance and gait training with graduated increases in mobility, maintenance of posture and alignment as well as joint function. Occupational therapy aims to improve everyday function with domestic and community tasks as well as driving and work. Home modifications, gait aids, orthotics and splints may be provided. Speech-language pathology input may be required in those with speech and swallowing problems, as well as to support communication in those who require ongoing breathing support (often through a tracheostomy). Nutritional support may be provided by the team and by dietitians. Psychologists may provide counseling and support. Psychological interventions may also be required for anxiety, fear and depression.

The second stage features the reabsorption of the initially extravasated fluid and albumin from the tissues, and it usually lasts 1 to 2 days. Intravascular fluid overload leads to polyuria and can cause flash pulmonary edema and cardiac arrest, with possibly fatal consequences. Death from SCLS typically occurs during this recruitment phase because of pulmonary edema arising from excessive intravenous fluid administration during the earlier leak phase. The severity of the problem depends on to the quantity of fluid supplied in the initial phase, the damage that may have been sustained by the kidneys, and the promptness with which diuretics are administered to help the patient discharge the accumulated fluids quickly. A recent study of 59 acute episodes occurring in 37 hospitalized SCLS patients concluded that high-volume fluid therapy was independently associated with poorer clinical outcomes, and that the main complications of SCLS episodes were recovery-phase pulmonary edema (24%), cardiac arrhythmia (24%), compartment syndrome (20%), and acquired infections (19%).

The prevention of episodes of SCLS has involved two approaches. The first has long been identified with the Mayo Clinic, and it recommended treatment with beta agonists such as terbutaline, phosphodiesterase-inhibitor theophylline, and leukotriene-receptor antagonists montelukast sodium.

The rationale for use of these drugs was their ability to increase intracellular cyclic AMP (adenosine monophosphate) levels, which might counteract inflammatory signaling pathways that induce endothelial permeability. It was the standard of care until the early 2000s, but was sidelined afterwards because patients frequently experienced renewed episodes of SCLS, and because these drugs were poorly tolerated due to their unpleasant side effects.

The second, more recent approach pioneered in France during the last decade (early 2000s) involves monthly intravenous infusions of immunoglobulins (IVIG), with an initial dose of 2 gr/kg/month of body weight, which has proven very successful as per abundant case-report evidence from around the world.

IVIG has long been used for the treatment of autoimmune and MGUS-associated syndromes, because of its potential immunomodulatory and anticytokine properties. The precise mechanism of action of IVIG in patients with SCLS is unknown, but it is likely that it neutralizes their proinflammatory cytokines that provoke endothelial dysfunction. A recent review of clinical experience with 69 mostly European SCLS patients found that preventive treatment with IVIG was the strongest factor associated with their survival, such that an IVIG therapy should be the first-line preventive agent for SCLS patients. According to a recent NIH survey of patient experience, IVIG prophylaxis is associated with a dramatic reduction in the occurrence of SCLS episodes in most patients, with minimal side effects, such that it may be considered as frontline therapy for those with a clear-cut diagnosis of SCLS and a history of recurrent episodes.

Hydroxyurea is a medication that can help to prevent acute chest syndrome. It may cause a low white blood cell count, which can predispose the person to some types of infection.

The suppression of CD4 T cells by HIV (or by immunosuppressive drugs) causes a decrease in the body's normal response to certain infections. Not only does this make it more difficult to fight the infection, it may mean that a level of infection that would normally produce symptoms is instead undetected (subclinical infection). If the CD4 count rapidly increases (due to effective treatment of HIV, or removal of other causes of immunosuppression), a sudden increase in the inflammatory response produces nonspecific symptoms such as fever, and in some cases a worsening of damage to the infected tissue.

There are two common IRIS scenarios. The first is the “unmasking” of an opportunistic infection. The second is the “paradoxical” symptomatic relapse of a prior infection despite microbiologic treatment success. Often in paradoxical IRIS, microbiologic cultures are sterile. In either scenario, there is hypothesized reconstitution of antigen-specific T cell-mediated immunity with activation of the immune system following HIV therapy against persisting antigen, whether present as intact organisms, dead organisms, or debris.

Though these symptoms can be dangerous, they also indicate that the body may now have a better chance to defeat the infection. The best treatment for this condition is unknown. In paradoxical IRIS reactions, the events will usually spontaneously get better with time without any additional therapy. In unmasking IRIS, the most common treatment is to administer antibiotic or antiviral drugs against the infectious organism. In some severe cases, anti-inflammatory medications, such as corticosteroids are needed to suppress inflammation until the infection has been eliminated.

Infections most commonly associated with IRIS include "Mycobacterium tuberculosis" and cryptococcal meningitis. Persons living with AIDS are more at risk for IRIS if they are starting for the first time, or if they have recently been treated for an opportunistic infection (OI). It is generally advised that when patients have low initial CD4 T cell count and opportunistic infection at the time of their HIV diagnosis, they receive treatment to control the opportunistic infections before HAART is initiated approximately two weeks later. This is true for most OIs, except for OIs involving the central nervous system.

People affected by the severest, often life-threatening, complications of cryoglobulinemic disease require urgent plasmapharesis and/or plasma exchange in order to rapidly reduce the circulating levels of their cryoglobulins. Complications commonly requiring this intervention include: hyperviscosity disease with severe symptoms of neurological (e.g. stroke, mental impairment, and myelitis) and/or cardiovascular (e.g., congestive heart failure, myocardial infarction) disturbances; vasculitis-driven intestinal ischemia, intestinal perforation, cholecystitis, or pancreatitis, causing acute abdominal pain, general malaise, fever, and/or bloody bowel movements; vasculitis-driven pulmonary disturbances (e.g. coughing up blood, acute respiratory failure, X-ray evidence of diffuse pulmonary infiltrates caused by diffuse alveolar hemorrhage); and severe kidney dysfunction due to intravascular deposition of immunoglobulins or vasculitis. Along with this urgent treatment, severely symptomatic patients are commonly started on therapy to treat any underlying disease; this treatment is often supplemented with anti-inflammatory drugs such as corticosteroids (e.g., dexamethasone) and/or immunosuppressive drugs. Cases where no underlying disease is known are also often treated with the latter corticosteroid and immunosuppressive medications.

Postinfection treatment involves a combination of antituberculosis antibiotics, including rifampicin, rifabutin, ciprofloxacin, amikacin, ethambutol, streptomycin, clarithromycin or azithromycin.

NTM infections are usually treated with a three-drug regimen of either clarithromycin or azithromycin, plus rifampicin and ethambutol. Treatment typically lasts at least 12 months.

Although studies have not yet identified an optimal regimen or confirmed that any therapeutic regimen produces sustained clinical benefit for patients with disseminated MAC, the Task Force concluded that the available information indicated the need for treatment of disseminated MAC. The Public Health Service therefore recommends that regimens be based on the following principles:

- Treatment regimens outside a clinical trial should include at least two agents.

- Every regimen should contain either azithromycin or clarithromycin; many experts prefer ethambutol as a second drug. Many clinicians have added one or more of the following as second, third, or fourth agents: clofazimine, rifabutin, rifampin, ciprofloxacin, and in some situations amikacin. Isoniazid and pyrazinamide are not effective for the therapy of MAC.

- Therapy should continue for the lifetime of the patient if clinical and microbiologic improvement is observed.

Clinical manifestations of disseminated MAC—such as fever, weight loss, and night sweats—should be monitored several times during the initial weeks of therapy. Microbiologic response, as assessed by blood culture every 4 weeks during initial therapy, can also be helpful in interpreting the efficacy of a therapeutic regimen.Most patients who ultimately respond show substantial clinical improvement in the first 4–6 weeks of therapy. Elimination of the organisms from blood cultures may take somewhat longer, often requiring 4–12 weeks.

There is antibiotic therapy for secondary infections caused by the parasite. However, surgical removal is usually the only way to get rid of the parasites.