In the majority of immunocompetent individuals, histoplasmosis resolves without any treatment. Antifungal medications are used to treat severe cases of acute histoplasmosis and all cases of chronic and disseminated disease. Typical treatment of severe disease first involves treatment with amphotericin B, followed by oral itraconazole.

Liposomal preparations of amphotericin B are more effective than deoxycholate preparations. The liposomal preparation is preferred in patients that might be at risk of nephrotoxicity, although all preparations of amphotericin B have risk of nephrotoxicity. Individuals taking amphotericin B are monitored for renal function.

Treatment with itraconazole will need to continue for at least a year in severe cases, while in acute pulmonary histoplasmosis, 6 to 12 weeks treatment is sufficient. Alternatives to itraconazole are posaconazole, voriconazole, and fluconazole. Individuals taking itraconazole are monitored for hepatic function.

Nocardiosis requires at least 6 months of treatment, preferably with trimethoprim/sulfamethoxazole or high doses of sulfonamides. In patients who do not respond to sulfonamide treatment, other drugs, such as ampicillin, erythromycin, or minocycline, may be added.

Treatment also includes surgical drainage of abscesses and excision of necrotic tissue. The acute phase requires complete bed rest; as the patient improves, activity can increase.

A new combination drug therapy (sulfonamide, ceftriaxone, and amikacin) has also shown promise.

Treatment usually involves high doses of steroids such as dexamethasone. While high doses of steroids may risk laminitis, low doses are associated with refractory cases. Antibiotics are used to treat any residual nidus of "S. equi". Non-steroidal anti-inflammatory drugs (NSAIDs), such as phenylbutazone or flunixin, may be useful to reduce fever and relieve pain. Intravenous DMSO is sometimes used as a free-radical scavenger and anti-inflammatory. Additionally, wrapping the legs may reduce edema and skin sloughing. Supportive care with oral or IV fluids may also be required.

Prognosis is good with early, aggressive treatment (92% survival in one study).

Early stage sepsis-associated purpura fulminans may be reversible with quick therapeutic intervention. Treatment is mainly removing the underlying cause and degree of clotting abnormalities and with supportive treatment (antibiotics, volume expansion, tissue oxygenation, etc.). Thus, treatment includes aggressive management of the septic state.

Purpura fulminans with disseminated intravascular coagulation should be urgently treated with fresh frozen plasma (10–20 mL/kg every 8–12 hours) and/or protein C concentrate to replace pro-coagulant and anticoagulant plasma proteins that have been depleted by the disseminated intravascular coagulation process.

Protein C in plasma in the steady state has a half life of 6- to 10-hour, therefore, patients with severe protein C deficiency and presenting with purpura fulminans can be treated acutely with an initial bolus of protein C concentrate 100 IU/kg followed by 50 IU /kg every 6 hours. A total of 1 IU/kg of protein C concentrate or 1 mL/kg of fresh frozen plasma will increase the plasma concentration of protein C by 1 IU/dL. Cases with comorbid pathological bleeding may require additional transfusions with platelet concentrate (10–15 mL/kg) or cryoprecipitate (5 mL/kg).

Established soft tissue necrosis may require surgical removal of the dead tissue, fasciotomy, amputation or reconstructive surgery.

For people who have severe congenital protein C deficiency, protein C replacement therapies are available, which is indicated and approved for use in the United States and Europe for the prevention of purpura fulminans. Protein C replacement is often in combination with anticoagulation therapy of injectable low molecular weight heparin or oral warfarin. Before initiating warfarin therapy, a few days of therapeutic heparin may be administered to prevent warfarin skin necrosis and other progressive or recurrent thrombotic complications.

Fulminant infection from meningococci bacteria in the bloodstream is a medical emergency and requires emergent treatment with adequate antibiotics. Benzylpenicillin was once the drug of choice with chloramphenicol as a good alternative in allergic patients. Ceftriaxone is an antibiotic commonly employed today. Hydrocortisone can sometimes reverse the adrenal insufficiency. Plastic surgery and tissue grafting are sometimes needed to treat tissue necrosis resulting from the infection.

Fungal meningitis is treated with long courses of high dose antifungal medications. The duration of treatment is dependent upon the causal pathogen and the patient's ability to stave off the infection; for patients with a weaker immune system or diabetes, treatment will often take longer.

No specific cure is known. Treatment is largely supportive. Nonsteroidal anti-inflammatory drugs (NSAIDs) are indicated for tender lymph nodes and fever, and corticosteroids are useful in severe extranodal or generalized disease.

Symptomatic measures aimed at relieving the distressing local and systemic complaints have been described as the main line of management of KFD. Analgesics, antipyretics, NSAIDs, and corticosteroids have been used. If the clinical course is more severe, with multiple flares of bulky enlarged cervical lymph nodes and fever, then a low-dose corticosteroid treatment has been suggested.

First-line therapy for disseminated or localized instances of pyoderma gangrenosum is systemic treatment by corticosteroids and ciclosporin. Topical application of clobetasol, mupirocin, and gentamicin alternated with tacrolimus can be effective.

Pyoderma gangrenosum ulcers demonstrate pathergy, that is, a worsening in response to minor trauma or surgical debridement. Significant care should be taken with dressing changes to prevent potentially rapid wound growth. Many patients respond differently to different types of treatment, for example some benefit from a moist environment, so treatment should be carefully evaluated at each stage.

Papules that begin as small "spouts" can be treated with Dakins Solution to prevent infection and wound clusters also benefit from this disinfectant. Wet to dry applications of Dakins can defeat spread of interior infection. Heavy drainage can be offset with Coban dressings. Grafting is not recommended due to tissue necrosis.

If ineffective, alternative therapeutic procedures include systemic treatment with corticosteroids and mycophenolate mofetil; mycophenolate mofetil and ciclosporin; tacrolimus; thalidomide; infliximab; or plasmapheresis.

There is currently a phase III trial for the use of the IL-1B modulating agent gevokizumab in treating the ulcers of pyoderma gangrenosum.

Itraconazole given orally is the treatment of choice for most forms of the disease. Ketoconazole may also be used. Cure rates are high, and the treatment over a period of months is usually well tolerated. Amphotericin B is considerably more toxic, and is usually reserved for immunocompromised patients who are critically ill and those with central nervous system disease. Patients who cannot tolerate deoxycholate formulation of Amphotericin B can be given lipid formulations. Fluconazole has excellent CNS penetration and is useful where there is CNS involvement after initial treatment with Amphotericin B.

Significant disease develops in fewer than 5% of those infected and typically occurs in those with a weakened immune system. Mild asymptomatic cases often do not require any treatment, and the symptoms will go away within a few months. Those with severe symptoms may benefit from anti-fungal therapy, which usually requires 3–6 months of treatment. There is a lack of prospective studies that examine optimal anti-fungal therapy for coccidioidomycosis.

On the whole, oral fluconazole and intravenous amphotericin B are used in progressive or disseminated disease, or in immunocompromised individuals. Amphotericin B used to be the only available treatment, although now there are alternatives, including itraconazole or ketoconazole may be used for milder disease. Fluconazole is the preferred medication for coccidioidal meningitis, due to its penetration into CSF. Intrathecal or intraventricular amphotericin B therapy is used if infection persists after fluconazole treatment. Itraconazole is used for cases that involve treatment of infected person's bones and joints. The antifungal medications posaconazole and voriconazole have also been used to treat coccidioidomycosis. Because the symptoms of valley fever are similar to the common flu and other respiratory diseases, it is important for public health professionals to be aware of the rise of valley fever and the specifics of diagnosis. Greyhound dogs often get valley fever as well, and their treatment regimen involves 6–12 months of Ketoconazole, to be taken with food.

There is no effective treatment for this condition. It has been reported that clearance of lesions can be done with melphalan and cyclophosphamide alone or in combination with prednisone. Both isotretinoin and etretinate have also been shown to improve the conditions. All medications listed can cause adverse symptoms, with isotretinoin and etretinate particularly dangerous since they are both teratogens. Other attempted treatments include interferon-alpha, cyclosporine, PUVA photochemotherapy, electron-beam therapy, IVIg, and dermabrasion. However, the overall prognosis for the disease is poor. There are reported instances of remission of the disease when treated with a combination of Revlimid and Dexamethasone over a 24-month period.

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.

Patient with KMS can be extremely ill and may need intensive care. They are at risk of bleeding complications including intracranial hemorrhage. The thrombocytopenia and coagulopathy are managed with platelet transfusions and fresh frozen plasma, although caution is needed due to the risk of fluid overload and heart failure from multiple transfusions. The possibility of disseminated intravascular coagulation, a dangerous and difficult-to-manage condition, is concerning. Anticoagulant and antiplatelet medications can be used after careful assessment of the risks and benefits.

Fungal pneumonia can be treated with antifungal drugs and sometimes by surgical debridement.

Generally, treatment of the underlying vascular tumor results in resolution of KMS. If complete surgical resection is feasible, it provides a good opportunity for cure (although it can be dangerous to operate on a vascular tumor in a patient prone to bleeding, even with appropriate surgical subspecialists involved).

If surgery is not possible, various other techniques can be used to control the tumor:

The prognosis of nocardiosis is highly variable. The state of the host's health, site, duration, and severity of the infection all play parts in determining the prognosis. As of now, skin and soft tissue infections have a 100% cure rate, and pleuropulmonary infections have a 90% cure rate with appropriate therapy. The cure rate falls to 63% with those infected with dissemented nocardiosis, with only half of those surviving infections that cause brain abscess. Additionally, 44% of people who are infected in the spinal cord/brain die, increasing to 85% if that person has an already weakened immune system. Unfortunately, there is not a preventative to nocardiosis. The only recommendation is to protect open wounds to limit access.

Conventional "amphotericin B desoxycholate" (AmB: used since the 1950s as a primary agent) is known to be associated with increased drug-induced Nephrotoxicity (Renal toxicity) impairing Renal function. Other formulations have been developed such as lipid soluble formulations to mitigate such side-effects as direct proximal and distal tubular cytotoxicity. These include liposomal amphotericin B, "amphotericin B lipid complex" such as Abelcet (brand) "amphotericin B phospholipid complex" also as "AmBisome Intravenous", or "Amphotec Intravenous" (Generic; Amphotericin B Cholesteryl Sul) and, "amphotericin B colloidal dispersion", all shown to exhibit a decrease in nephrotoxicity. The later was not as effective in one study as "amphotericin B desoxycholate" which had a 50% murine morbidity rate versus zero for the AmB colloidal dispersion.

The cost of AmB deoxycholate in 2015, for a patient of at 1 mg/kg/day dosage, was approximately $63.80, compared to 5 mg/kg/day of liposomal AmB at $1318.80. This may be a concern in resource-limited settings.

People with AIDS are given macrolide antibiotics such as azithromycin for prophylactic treatment.

People with HIV infection and less than 50 CD4+ T-lymphocytes/uL should be administered prophylaxis against MAC. Prophylaxis should be continued for the patient's lifetime unless multiple drug therapy for MAC becomes necessary because of the development of MAC disease.

Clinicians must weigh the potential benefits of MAC prophylaxis against the potential for toxicities and drug interactions, the cost, the potential to produce resistance in a community with a high rate of tuberculosis, and the possibility that the addition of another drug to the medical regimen may adversely affect patients' compliance with treatment. Because of these concerns, therefore, in some situations rifabutin prophylaxis should not be administered.

Before prophylaxis is administered, patients should be assessed to ensure that they do not have active disease due to MAC, M. tuberculosis, or any other mycobacterial species. This assessment may include a chest radiograph and tuberculin skin test.

Rifabutin, by mouth daily, is recommended for the people's lifetime unless disseminated MAC develops, which would then require multiple drug therapy. Although other drugs, such as azithromycin and clarithromycin, have laboratory and clinical activity against MAC, none has been shown in a prospective, controlled trial to be effective and safe for prophylaxis. Thus, in the absence of data, no other regimen can be recommended at this time.The 300-mg dose of rifabutin has been well tolerated. Adverse effects included neutropenia, thrombocytopenia, rash, and gastrointestinal disturbances.

Both lyme disease and STARI can be treated with antibiotics, particularly doxycyclin.

Prognosis depends on the pathogen responsible for the infection and risk group. Overall mortality for "Candida" meningitis is 10-20%, 31% for patients with HIV, and 11% in neurosurgical cases (when treated). Prognosis for "Aspergillus" and coccidioidal infections is poor.

The therapy of an acute TTP episode has to be started as early as possible. The standard treatment is the daily replacement of the missing ADAMTS13 protease in form of plasma infusions or in more severe episodes by plasma exchange. In the latter the patients plasma is replaced by donated plasma. The most common sources of ADAMTS13 is platelet-poor fresh frozen plasma (FFP) or solvent-detergent plasma.

The benefit of plasma exchange compared to plasma infusions alone may result from the additional removal of ULVWF. In general both plasma therapies are well tolerated, several mostly minor complications may be observed. The number of infusion/exchange sessions needed to overcome a TTP episode are variable but usually take less than a week in USS. The intensive plasma-therapy is generally stopped when platelet count increases to normal levels and is stable over several days.

PTLD may spontaneously regress on reduction or cessation of immunosuppressant medication, and can also be treated with addition of anti-viral therapy. In some cases it will progress to non-Hodgkin's lymphoma and may be fatal. A phase 2 study of adoptively transferred EBV-specific T cells demonstrated high efficacy with minimal toxicity.

Not all affected patients seem to need a regular preventive plasma infusion therapy, especially as some reach longterm remission without it. Regular plasma infusions are necessary in patients with frequent relapses and in general situations with increased risk to develop an acute episode (as seen above) such as pregnancy. Plasma infusions are given usually every two to three weeks to prevent acute episodes of USS but are often individually adapted.