Opportunistic infections

What are opportunistic infections?

Opportunistic infections can be viral, bacterial, fungal or parasitic infections (bugs). They occur in patients with a weakened or compromised immune system, occurring secondarily to another condition such as HIV-AIDS.

What are some common opportunistic infections?

Common opportunistic infections include (but are not limited to):

• Candidiasis infections of the gastrointestinal or genitourinary tract, including non-albicans candida infections
• Coccidioidomycosis (San Joaquin Valley Fever)
• Cryptococcosis
• Cytomegalovirus (CMV)
• Cryptosporidiosis of the greater intestines
• Herpes simplex-related bronchitis, pneumonitis or esophagitis
• Histoplasmosis
• Recurrent pneumonia
• Tuberculosis (TB)
• Toxoplasmosis
• Mycobacterium avium complex (MAC).

What are the possible sources of opportunistic infections?

Sources of pathogens which cause opportunistic infections vary widely, but can include:

• Untreated water or soils
• Unwashed foods, undercooked eggs or meats, unpasteurised dairy or juices or raw, sprouted grains
• Contact with the bodily fluids of infected individuals
• Contact with animal faeces.

What are the signs and symptoms of an opportunistic infection?

Because of the wide range of opportunistic infections, signs and symptoms vary widely. However, some common symptoms can include:

• Fever
• Pain/headaches
• Night sweats/chills
• Painful joints
• Loss of appetite/unexplained weight loss
• Enlarged lymph nodes
• Swelling.

Who is at risk for an opportunistic infection?

Risk factors for opportunistic infections include:

• Diagnosis of HIV-AIDS
• History of cancer
• Immunosuppressive agents/long-term corticosteroid therapy
• Primary immunodeficiency, such as severe combined immunodeficiency or selective IgA deficiency.

How are opportunistic infections diagnosed?

The diagnosis of opportunistic infection is based on several factors, including:

• Patient history and physical examination
• Results of blood tests
• Culture and sensitivity tests to determine the underlying pathogen.

How are opportunistic infections treated?

Treatment will depend on the type of infection, but can include:

• Antibiotics (such as azithromycin or clarithromycin)
• Antifungals (such as fluconazole or voriconazole)
• Antivirals (such as aciclovir or valaciclovir)
• Antiretroviral therapy (ART) to reduce AIDS-related opportunistic infections
• Antibiotic prophylaxis.

How can opportunistic infections be prevented?

Prevention of opportunistic infections consists largely of healthy lifestyle choices, including:

• Frequent medical visits
• Compliance with the medication regimen
• Immunisation/vaccination as approved by a physician
• Hand hygiene
• Balanced, adequate nutrition
• Stress management techniques
• Regular exercise as tolerated
• Limiting exposure to others who are ill
• Safe sexual practices
• Avoidance of handling cat litter or other animal faeces
• Avoidance of undercooked/unwashed foods, unpasteurised dairy or juices or raw sprouted grains.