Immunosuppression Infections

Dunn, D. L. (1990). Problems related to immunosuppression. Infection and malignancy occurring after solid organ transplantation.Crit. Care Clin. 6, 955-977. 

Secondary immunodeficiencies (9) are much more common than primary ones and frequently occur as a result of immaturity of the immune system in premature infants, immunosuppressive therapy, or surgery and trauma. Illnesses, particularly when prolonged and serious, have been associated with secondary immunodeficiencies, some of which may be reversible. Acquked immune deficiency syndrome (AIDS) (10—12) may be considered a secondary immunodeficiency disease caused by the human immunodeficiency vimses HIV-1 or HIV-2. Hitherto unknown, the disease began to spread in the United States during the latter part of the 1970s. The agent responsible for this infection has been isolated and identified as a retrovims. 

Nonspecific immunosuppressive therapy in an adult patient is usually through cyclosporin (35), started intravenously at the time of transplantation, and given orally once feeding is tolerated. Typically, methylprednisone is started also at the time of transplantation, then reduced to a maintenance dose. A athioprine (31) may also be used in conjunction with the prednisone to achieve adequate immunosuppression. Whereas the objective of immunosuppression is to protect the transplant, general or excessive immunosuppression may lead to undesirable compHcations, eg, opportunistic infections and potential malignancies. These adverse effects could be avoided if selective immunosuppression could be achieved. Suspected rejection episodes are treated with intravenous corticosteroids. Steroid-resistant rejection may be treated with monoclonal antibodies (78,79) such as Muromonab-CD3, specific for the T3-receptor on human T-ceUs. Alternatively, antithymocyte globulin (ATG) may be used against both B- and T-ceUs. 

Acyclovir is more effective the more serious the disease and the earher it is given. It has been shown to be efficacious when used systemicaHy in the prophylaxis of HSV infections in immunosuppressed patients, ie, bone marrow transplant recipients (67). Acyclovir therapy appears to be superior to ara-A in the treatment of herpes simplex encephaUtis in humans (68). 

Amphibians. Immunosuppression has been shown to occur during metamorphosis in several amphibians, and appears to be hormonally regulated. The disappearance of 11 populations of toad from Colorado was associated with immune suppression, and frog mortalities have been associated with infection by a commonly occurring bacteria, Aeromonas hydrophila the cause of the immunosuppression in these animals has not been elucidated. " ... 

Systemic mycoses are caused either by true pathogenic fungi (endemic in distinct areas of USA/South America) or by opportunistic fungi that induce severe infections in immunosuppressed patients. The arsenal for the treatment of deep organ mycoses is relatively small Amph B, 5FC, azoles (FLU, ITRA, voriconazole (NBA filing)) and CAS. 

Inhibition of immunomodulatory cytokines (Fig. 1) Anti-T-cell receptor antibodies Muromonab (OKT3, Orthoclone ) binds to the CD3 complex of the T-cell receptor and induces depletion of T-lymphocytes. It is applied to prevent acute rejection of kidney, liver, and heart allografts. Rapid side effects (within 30-60 min) include a cytokine release syndrome with fever, flu-like symptoms, and shock. Late side effects include an increased risk of viral and bacterial infections and an increased incidence of lymphproliferative diseases due to immunosuppression. 

Varizella zoster vitus (VZV) is a highly contagious herpesvirus causing chickenpox upon primary infection. After recovery, the vims stays dormant in nerve roots. Weakening of the immune system, e.g. in people over the age of 60 or under immunosuppressive therapy, can lead to reactivation of VZV. This recurrence causes shingles (herpes zoster), a painful rash that develops in a well-defined band corresponding to the area enervated by the affected nerve cells. 

Q Risk for Infection related to inadequate defense mechanisms (immunosuppression)... 

RlSK FOR IN FECTION IN IM M U NOSUPPRESSED PATIEN TS. When patients are immunosuppressed, they are at increased risk for bacterial or other infection. The patient is protected against individuals with upper respiratory infection. All caregivers are reminded to use good handwashing technique... 

Most herbalists recommend that echinacea should be taken at the initial signs of infection, when symptomsfirst become apparent. Smalt repeated dosesthroughout the day may be better than taking larger doses less frequently. Because it isan immunosuppressant, the herb should not be taken for more than eight consecutive weeks. Seven to fourteen days of treatment is usually sufficient. 

Cidofovir (Fig. 2) has been formally approved for the treatment of CMV retinitis in AIDS patients, where it is administered intravenously at a dose not exceeding 5 mg/kg once weekly during the first two weeks (and every other week thereafter). Cidofovir is also used off label for the treatment of human papilloma virus (HPV) infections (i.e., cutaneous warts, anogenital warts, laryngeal and pharyngeal papilloma), polyomavirus [i.e., progressive (i.e., multifocal leukoencephalopathy (PML)], adenovirus, herpesvirus, and poxvirus (i.e., molluscum contagiosum) infections, where it can be administered intravenously (at a dose of < 5 mg/kg once weekly or every other week) or topically as a 1% gel or cream (De Clercq and Holy 2005). Especially in immunosuppressed patients (i.e., transplant recipients), local treatment of HPV-associated lesions has often yielded spectacular results (Bonatti etal.2007). 

Moatti JP, Spire B, Kazatchkine M (2004) Drug resistance and adherence to HIV/AIDS antiretroviral treatment against a double standard between the north and the south, AIDS I8 S55-S6I Moore RD, Chaisson RE (1997) Costs to Medicaid of advancing immunosuppression in an urban HIV-infected patient population in Maryland, J Acquir Immune Defic Syndr Hum Retrovirol 16 223-231... 

A patient s resistance is cmcial in determining the outcome of a medicament-borne infection. Hospital patients are more exposed and susceptible to infection than those treated in the general community. Neonates, the elderly, diabetics and patients traumatized by surgeiy or accident m have impaired defence mechanisms. People suffering fiom leukaemia and those treated with immunosuppressants are most vulnerable to infection there is a strong case for providing all medicines in a sterile form for these patients. 

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