Opportunistic disease, with AIDS

Increasingly, this opportunistic disease occurs in those with a suppressed immune system, especially those with AIDS. The only effective treatment for cryptosporidiosis in AIDS patients who do not respond readily to therapy is spiramycin (48). 

Progressive multifocal leukoencephalopathy (PML) is historically a rare demyelinating disease that is usually associated with disorders of the reticuloendothelial system, neoplasias and immunosuppressive therapy [1, 2]. However, it has become more important in clinical medicine because it is frequently seen as an opportunistic secondary infection in immunocompromised persons with AIDS. PML is characterized by focal lesions that are noninflammatory and caused by infection of oligodendrocytes with the JC papovavirus. 

The most common opportunistic diseases and their frequencies found before death in patients with AIDS between 1990 and 1994 were Pneumocystis carinii pneumonia (PCP), Mycobacterium avium complex, and cytomegalovirus disease. 

The concentrations of nitrite or nitrate in the sera of patients infected with H IV-1 are substantially raised, especially in those with low CD4 cell counts [118]. However, during HIV-1 infection, it is difficult to find out whether the NO production is attributable to virus replication or to opportunistic infections, or both. In vitro there is a substantial rise in nitrite concentrations from blood mononuclear cells and polymorphonuclear leucocytes from patients with AIDS, especially in those with neurological disorders and pulmonary disease caused by intracellular opportunistic pathogens [121]. Interestingly, the serum concentrations of nitrate are positively correlated with plasma and cell-associated viral loads, which suggests that HIV-1 may induce NO synthesis in vivo [119]. However, the results clearly show that there is a close relation between viral replication and iNOS expression or peaks of plasma nitrate in the absence of any opportunistic infections, in either in macaques or infected patients [119, 122, 123]. 

Considerable neuromuscular involvement also occurs in patients with AIDS.47 100 Peripheral neuropathies, myopathies, and various CNS manifestations (dementia, other psychological manifestations) can occur directly from HIV infection or secondarily, due to some other opportunistic infection.31 85 100 Likewise, peripheral neuropathies are a common side effect of certain anti-HIV drugs (didanosine, stavudine, zal-citabine), and myopathies are a side effect of zidovudine therapy.63 Patients with HIV disease often have painful symptoms such as joint pain, back pain, and pain related to neuropathies and myopathies.100 Hence, HIV disease can often be regarded as a degenerative neuromuscular disorder from the standpoint of a rehabilitation professional. Therapists can therefore help improve function and decrease pain in patients with HIV infection and AIDS.1 33... 

The infectious killer disease, tuberculosis (TB), is the leading cause of death worldwide from a single human pathogen, claiming more adult lives than diseases such as acquired immunodeficiency syndrome (AIDS), malaria, diarrhea, leprosy, and all other tropical diseases combined. The organism usually responsible, the tubercle bacillus, Mycobacterium tuberculosis (MT), was discovered by Robert Koch in 1882. However, M. bovis, which infects cattle, may also infect humans, and M. africanum is a cause of TB in West Africa. Furthermore, a number of normally nonpathogenic mycobacteria, especially M. avium, M. intracellulare, and M. scrofulaceum, cause opportunistic infectious disease in patients with AIDS. Pulmonary TB, the most common type of the disease, is usually acquired by inhalation of the bacillus from an infectious patient and causes irreversible lung destruction (Newton et al., 2000). 

CMV retinitis is the most common opportunistic eye infection in patients with AIDS and immunocompromised transplant patients. Antiviral medications used in the treatment of CMV are generally administered in two stages induction therapy, to achieve disease regression, followed by maintenance therapy. The incidence of CMV retinitis has decreased significantly with the advent of HAART for AIDS, and antiviral therapy for CMV may often be discontinued in patients who respond favorably to HAART and achieve an elevation in CD4 cell levels above lOO/pl. Refer to Chapter 32 fiar the drug treatment of ocular CMV infections. 

A 35-year old Caucasian man with AIDS and multiple opportunistic infections, including Mycobacterium kansasii and Mycobacterium avium complex (MAC) disease developed moderate to severe primary sensorineural hearing loss after 4—5 months of therapy with oral azithromycin 500 mg/day. Other medications included ethambutol, isoniazid, rifabutin, ciprofloxacin, co-trimoxazole, fluconazole, zidovudine (later switched to stavudine), lamivudine, indinavir, methadone, mod-ified-release oral morphine, pseudoephedrine, diphenhydramine, megestrol acetate, trazodone, sorbitol, salbutamol by metered-dose inhaler and nebulizer, ipratropium, and oral morphine solution as needed. Significant improvement of the hearing impairment was documented 3 weeks after drug withdrawal. 

Data regarding the clinical presentation of CMV retinitis, pattern of infection, disease course, and complications have been obtained in the last two decades because of its association with AIDS. Therapy for AIDS has been greatly improved since the mid-1990s with the development and use of highly active antiretroviral therapy (HA ART). HA ART therapy improves systemic immune function in many patients with AIDS, and thus has drastically altered the incidence and clinical features of CMV retinitis and other opportunistic infections (4). 

AIDS (acquired immunodeficiency syndrome) is the final stage of disease caused by infection with HIV. In this stage, the vims infection has severely affected the immune system, causing a depletion of CD4+ T-helper cells. AIDS is characterized by the manifestation of typical diseases caused by opportunistic infections (Pneumocystis carinii pneumonia, CMV retinitis, candidiasis of the esophagus, cerebral toxoplasmosis), neurological manifestations, cachexia, or certain tumors (Kaposi sarcoma of the skin, B-cell lymphoma). 

Parasitic diseases, such as trypanosomiasis, malaria, and leishmaniasis, affect himdreds of millions people around the world, mainly in underdeveloped countries. They are also the most common opportunistic infections that affect patients with acquired immunodeficiency syndrome (AIDS). Globally, malaria occupies the first place, but in Latin America, Chagas disease (American Trypanosomiasis) is the most relevant parasitic disease that produces morbidity and mortahty in low-income individuals. 

The major 1987 changes were to include patients with laboratory evidence of HIV infection and also have HIV encephalopathy, HIV wasting syndrome, and one of the range of AIDS-indicating diseases (cancers and opportunistic infections), provided immunodeficiency for other causes is excluded. 

Mycobacterium is a genus of bacteria that has characteristic cell walls and unusual staining properties. AIDS patients are most commonly infected with an atypical form of tuberculosis bacterium called Mycobacterium avium inter-cellulare. This bacterium does not normally cause disease in healthy people, but in AIDS patients, it may cause tuberculosis-like disease in the lungs. The infection can also involve numerous other tissues, such as the bone marrow, and bacteria may be present in the blood at very high levels. Patients with this opportunistic infection will have fevers and low number of white blood cells. These infections are often resistant to drugs. 

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