How to Manage Opportunistic Infections When HIV Positive

People who are HIV positive frequently suffer from a weakened immune system, which makes them vulnerable to many opportunistic infections. People with HIV or AIDS must manage such vulnerabilities carefully, because these infections can be difficult to treat and sometimes lethal for HIV positive individuals. The most common and serious of these is pneumocystis carinii. Others include cytomegalovirus, toxoplasmosis, tuberculosis, hepatitis C virus and mycobacterium avium. 

Things You'll Need

• Regular medical checkups and blood cell monitoring

Instructions:

Manage and Prevent Opportunistic Infections When HIV Positive

1.  Take all medications in your HIV or AIDS treatment regiment exactly as prescribed.

2. Avoid activities or employment that increase your risk of infection or put you in proximity to people who are sick. Talk to your doctor before taking a position in a hospital, prison or homeless shelter.

3. Wash your hands frequently and avoid any unprotected contact with the biological waste of human beings or animals in any environment, from sexual contact to swimming in a swimming pool.

4. Monitor your CD4 cell count and ask your doctor to prescribe trimethoprim-sulfamethoxazole (TMP-SMX) to protect you against pneumocystis carinii (PCP) if your CD4 count falls below 200. TMP-SMX is also recommended if you have a temperature of 100 F or more that last two weeks or more or if you suffer from thrush or another fungal infection in your throat or mouth.

5. Ask your doctor whether you should receive a medication such as clarithromycin, azithromycin, or rifabutin to reduce your chance of getting mycobacterium avium (MAC) if your T-cell count falls below 50.

6. Manage your jobs or activities to stay clear of fungus by avoiding construction or demolition, farming or gardening, lab work or work with bridges, caves, chimneys or HVAC systems.

7. Protect yourself from HCV by taking precautions such as using a condom during sex, avoiding contact with any other person's blood or with implements such as razors, toothbrushes, drug works or tattoo or piercing tools that could have blood on them.

8. Cook all meat, eggs and other animal products thoroughly and never eat raw meat or eggs.

9. Manage your weight and nutrition to avoid dramatic weight loss or wasting.

Get Immediate Treatment for Opportunistic Infections When HIV Positive

10. Report any symptoms of opportunistic infections to your doctor and seek immediate medication and treatment if you are HIV positive.

11. Continue to take all medications for opportunistic infections, even after you begin to feel better or believe yourself to be cured or finished with the infection. Cease taking such medications only when specifically told to stop the medication by your doctor. Failure to complete the full course of medication can subject you to a more intense, potentially lethal return of the infection.

Tips & Warnings

• One of the dangers associated with some HIV-related opportunistic infections is that some, such as tuberculosis (TB), can be spread to other people whether or not they are HIV positive.

 

 

 

 

 

HIV/AIDS and Opportunistic Infections

HIV (human immunodeficiency virus) attacks the body's white blood cells -- specifically a subset called CD4 or helper T cells. This attack allows opportunistic infections to take advantage of a weakened immune system, and can lead to illnesses, cancers, or neurological problems. If you have HIV and develop an opportunistic infection, your HIV infection may have progressed to AIDS (acquired immunodeficiency syndrome). But with careful monitoring, self-care, and treatment, you can prevent many infections and stay healthier if you do develop an infection.

Where HIV Opportunistic Infections Come From

A wide variety of germs can cause HIV opportunistic infections. These include bacteria, viruses, protozoa, or fungi. Even before you have HIV, you have many of these in your body. But a healthy immune system normally keeps them under control. These are examples of other places where you can pick up germs that cause HIV opportunistic infections:

• Unwashed raw foods
• Soil or water
• Contact with animal feces
• Contact with other people, through unsafe sex or in places where germs are common, such as hospitals, day care centers, or schools
• Contact with blood through sharing needles or intravenous drugs

Common HIV Opportunistic Infections

Almost any disease can become an HIV opportunistic infection when the immune system is weak. Some are more common than others, though. And some are more likely to occur at certain levels of CD4 counts than others. Here are some of the more common HIV opportunistic infections:

• Candidiasis (thrush): a fungal infection in the mouth, throat, or vagina.
• Cryptococcus neoformans (Crypto): a fungus that can lead to meningitis, a serious inflammation of membranes surrounding the brain and spinal cord.
• Cryptosporidiosis and microsporidiosis: protozoa affecting the gastrointestinal tract.
• Cytomegalovirus (CMV): a virus that causes eye disease and can lead to blindness. It can also cause severe diarrhea and ulcers.
• Herpes simplex: viruses that can cause severe genital or cold sores.
• Mycobacterium avium complex (MAC): a bacterium that can cause fevers, problems with digestion, and serious weight loss.
• Pneumocystis pneumonia (PCP): a fungus that can cause fatal pneumonia.
• Progressive multifocal leukoencephalopathy (PML): a virus affecting the brain.
• Toxoplasmosis (Toxo): a protozoa that sometimes causes encephalitis, an inflammation of the brain.
• Tuberculosis (TB): a bacterial infection that attacks the lungs and can invade other organs. TB can lead to meningitis at its most severe.

There are some differences between women and men with respect to opportunistic infections. Here are a few of them:

• Men are eight times more likely to develop a cancer called Kaposi's sarcoma.
• Women are more likely to develop bacterial pneumonia and herpes simplex infections.
• Women are also more at risk for certain infections that can lead to cancers of the reproductive system.

Preventing HIV Opportunistic Infections

Some of the germs that cause HIV opportunistic infections are so widespread they're difficult to avoid. But you can take steps to prevent some.

• Make nutritious food choices to help boost your immune system.
• Get regular exercise, but check with your doctor before starting an exercise program.
• Get enough rest and learn new ways to manage stress.
• If you smoke or use drugs, get help quitting.
• Thoroughly wash and cook all foods. Avoid raw or undercooked meats or eggs and unpasteurized dairy foods. Thoroughly wash and disinfect hands, knives, cutting boards, and counters where you prepare food.
• Keep cats indoors to prevent their exposure to germs that could harm you. Have others handle cat litter or pick up dog feces -- or use gloves if you do.
• Practice safe sex.
• Use a towel on shared gym equipment. Use a different towel to dry yourself.
• Avoid swallowing water in pools, lakes, or streams that might be contaminated.
• Get vaccinations your doctor recommends.
• Take HIV drugs to keep your immune system strong.

If your CD4 count stays up, HIV opportunistic infections are less likely to be a problem. However, if your CD4 count is low, you can take preventive drugs, called prophylaxis, to reduce your chances of becoming sick. Federal guidelines recommend anti-HIV therapy if CD4 cell counts fall to 350 or below or if you have symptoms of HIV disease -- even if cell counts are not low.

Diagnosing and Treating HIV-Related Opportunistic Infections

Many germs that cause HIV-related opportunistic infections are very common. You can undergo lab tests to learn which ones are already in your body. This will help your doctor know how to treat them and which ones you can focus on preventing. Unfortunately, as many as one out of four people in the U.S. aren't aware they're infected with HIV. Some don't find out until they end up in the hospital with a serious HIV-related opportunistic infection.
HIV makes copies of itself more quickly when HIV-related opportunistic infections occur. So early treatment is important not only to prevent serious results of infection, but to also preserve the immune system. Here's what you can do to receive diagnosis and treatment as early as possible.

• See your doctor regularly -- two to 12 times a year. Make sure you have a primary care doctor who is experienced in HIV treatment and knows how to coordinate care well with other specialists.
• If you're a woman, get regular pelvic exams and Pap tests to spot infections, precancers, or cancers of the reproductive system.
• Keep a record of symptoms to help with diagnosis of HIV-related opportunistic infections. These include fever for more than two days, weight loss, a change in vision, or mouth problems, skin problems, or breathing problems.
• Go to your doctor if you have any new or unusual symptoms. Don't wait for your regularly scheduled visit.
• Prepare for appointments by coming with questions and a way to take notes.
• Follow through with your course of treatment. Don't quit early.

Preventing Recurrence of HIV-Related Opportunistic Infections

Take the maintenance therapy your doctor prescribes. This is medication to prevent recurrence of infections. As your immune system recovers, you may be able to stop taking these at some point.

 

What are opportunistic infections? 

People with advanced HIV infection are vulnerable to infections and malignancies that are called 'opportunistic infections' because they take advantage of the opportunity offered by a weakened immune system.

A partial list of the world's most common HIV-related opportunistic infections and diseases includes:

• Bacterial diseases such as tuberculosis, MAC, bacterial pneumonia and septicaemia (blood poisoning)
• Protozoal diseases such as toxoplasmosis, microsporidiosis, cryptosporidiosis, isopsoriasis and leishmaniasis
• Fungal diseases such as PCP, candidiasis, cryptococcosis and penicilliosis
• Viral diseases such as those caused by cytomegalovirus, herpes simplex and herpes zoster virus
• HIV-associated malignancies such as Kaposi's sarcoma, lymphoma and squamous cell carcinoma.

Different conditions typically occur at different stages of HIV infection. In early HIV disease people can develop tuberculosis, malaria, bacterial pneumonia, herpes zoster, staphylococcal skin infections and septicaemia. These are diseases that people with normal immune systems can also get, but with HIV they occur at a much higher rate. It also takes longer for a person with HIV to recover than it takes for someone with a healthy immune system.

When the immune system is very weak due to advanced HIV disease or AIDS, opportunistic infections such as PCP, toxoplasmosis and cryptococcosis develop. Some infections can spread to a number of different organs, which is known as 'disseminated' or 'systemic' disease. Many of the opportunistic infections that occur at this late stage can be fatal.

Why is there still a need to prevent and treat opportunistic infections?

Highly Active Antiretroviral Therapy (HAART) can reduce the amount of HIV in someone's body and restore their immune system. The introduction of HAART has dramatically reduced the incidence of opportunistic infections among HIV-positive people who have received the drugs. Yet the prevention and treatment of opportunistic infections remains essential.

Treating patients on an HIV ward in a Ugandan hospital

Around the world, millions of people living with HIV in resource-poor communities have no access to antiretroviral drugs. And even where the drugs are available, they do not entirely remove the need for preventing and treating opportunistic infections. Usually it is advisable for people with acute opportunistic infections to begin HIV treatment right away, especially if the infection is difficult to treat. However in certain cases it may be better to delay beginning HIV treatment and instead only to administer treatment for the opportunistic infection, especially if there are concerns about drug interactions or overlapping drug toxicities.
Those who have already started taking antiretrovirals may require other drugs in certain circumstances. In particular, some opportunistic infections may be unmasked shortly after starting HIV treatment as the immune system starts to recover, and these may require specific treatment. Measures to prevent and treat opportunistic infections become essential if antiretrovirals stop working because of poor adherence, drug resistance or other factors.

Providing prevention and treatment of opportunistic infections not only helps HIV-positive people to live longer, healthier lives, but can also help prevent TB and other transmissible opportunistic infections from spreading to others.

Prevention of HIV-related opportunistic infections

HIV-positive people can reduce their exposure to some of the germs that threaten their health. They should be especially careful around uncooked meat, domestic animals, human excrement and lake or river water. However there is no practical way to reduce exposure to the germs that cause candidiasis, MAC, bacterial pneumonia and other diseases because they are generally common in the environment.

Co-trimoxazole

Several HIV-related infections (including tuberculosis, bacterial pneumonia, malaria, septicaemia and PCP) can be prevented using drugs. This is known as drug prophylaxis. One particular drug called co-trimoxazole (also known as septra, bactrim and TMP-SMX) is effective at preventing a number of opportunistic infections and has been shown to significantly reduce mortality among HIV-positive individuals initiating antiretroviral therapy.¹ Although the drug is both cheap and widely available, many countries have still failed to implement policies to provide nationwide coverage of the drug.
 
The World Health Organisation (WHO) recommends that, in resource-limited settings, the following groups of people should begin taking co-trimoxazole:

• HIV-exposed infants and children, starting at 4-6 weeks after birth, or at first contact with health care, and continued until HIV infection is excluded
• HIV-positive children less than 1 year old
• HIV-positive children aged 1-4 years who have mild, advanced or severe symptoms of HIV disease, or a CD4 count below 25%
• HIV-positive adults and adolescents who have mild, advanced or severe symptoms of HIV disease, or a CD4 count below 350 cells per ml
• HIV-positive people with a history of treated PCP.

According to WHO guidelines, treatment of HIV-positive children should continue until at least age five. In general treatment of adults and children should continue indefinitely, though it may sometimes be stopped following successful antiretroviral treatment.

Some of the worst affected countries may choose to treat all infants and children born to mothers confirmed or suspected of living with HIV, until HIV infection is excluded. They may also choose to treat everyone who is diagnosed with HIV, regardless of symptoms or CD4 count.

Drug prophylaxis is sometimes recommended even for those who have started ART if they have very weak immune systems or are otherwise considered to be especially vulnerable. They may be advised to stop taking the drugs if their immune system recovers.

For people who have already contracted an opportunistic infection and undergone successful treatment, secondary prophylaxis may be advisable to prevent recurrence. This applies to diseases such as tuberculosis, salmonella, cryptococcosis and PCP.

Treatment of HIV-related opportunistic infections

Some opportunistic infections are easier to treat than others. Effective treatment depends on health services being able to procure, store, select and administer the necessary drugs and to provide related treatment, care and diagnostic services to monitor health status and treatment response.

A few opportunistic infections and symptoms such as candidiasis of the mouth, throat or vagina (thrush), herpes zoster (shingles) and herpes simplex can be managed effectively through home based care. In a home-based care setting diagnosis is made by observing symptoms.

Some opportunistic infections may be diagnosed by observation or using a microscope, and treated where there is minimal health infrastructure. Such infections include pulmonary tuberculosis and cryptococcal meningitis.

In a medium infrastructure setting, the facilities available include X-ray equipment and culture facilities. Using these, opportunistic infections such as extra-pulmonary tuberculosis, cryptosporidiosis, isopsoriasis, PCP and Kaposi's sarcoma can be diagnosed and treated.

Opportunistic infections such as toxoplasmosis, MAC and cytomegalovirus infection can be diagnosed and treated in places with advanced infrastructure. Treating these infections is often impossible in resource poor countries. Many developing countries lack the advanced equipment and infrastructure (such as CT scanning) needed to treat these more complex infections.

See our page on AIDS and pain for information on treating pain associated with opportunistic infections.

Individual opportunistic infections

The following are just a few of the conditions that particularly affect people living with HIV.

Bacterial pneumonia

Pneumonia can be caused by various bacteria. Symptoms among HIV-positive people are much the same as in those without HIV infection, and include chills, rigours, chest pain and pus in the sputum. The vaccine PPV can protect people against some of the more common pneumonia-causing bacteria, and is recommended in the US.
Because other forms of respiratory infection, including PCP, are common among HIV-infected people, doctors must be certain of diagnosis before administering antibiotics. This may require a chest radiograph, blood cultures, a white blood cell count and tests to eliminate other infections. Treatment is usually aimed at the most commonly identified disease-causing bacteria.

Candidiasis

There are two main types of candidiasis: localised disease (of the mouth and throat or of the vagina) and systemic disease (of the oesophagus, and disseminated disease). HIV-positive women commonly acquire the mouth and throat variant (usually known as thrush or OPC). It is believed to occur at least once in the lifetime of all HIV-infected patients. OPC in HIV-positive patients indicates a decline in immunodeficiency and, when ART is absent, is a sign of the onset of AIDS. However, the vaginal variant is a common occurrence among HIV-negative women.

While OPC is not a cause of death, it causes severe discomfort. The symptoms of candidiasis of the vagina include itching and possibly a thick vaginal discharge. Candidiasis of the mouth and throat can cause oral pain and make swallowing difficult, the main symptom is creamy white legions in the mouth that can be scraped away. Oesophageal (gullet) candidiasis is a more serious condition which can cause pain in the chest that increases with swallowing. Disseminated candidiasis causes fever and symptoms in the organs affected by the disease (for example, blindness when it affects the eyes), and can be life threatening.

Localised disease may be treated at first with relatively inexpensive drugs such as nystatin, miconazole or clotrimazole. Systemic candidiasis requires treatment with systemic antifungal agents such as fluconazole, ketoconazole, itraconazole or amphotericin.

Cryptococcosis

Cryptococcosis is caused by a fungus that primarily infects the brain. It most often appears as meningitis and occasionally as pulmonary or disseminated disease. Untreated cryptococcal meningitis is fatal.

Cryptococcosis is relatively easy to diagnose. However, its treatment (either amphotericin B with or without flucytosine or in mild cases with oral fluconazole) and secondary chemoprophylaxis are often impossible in developing countries because of high cost and limited availability of the drugs required.

It is recommended that ART should be administered to those diagnosed with cryptococcal disease. In the case of cryptococcal meningitis there are risks of initiating ART as there is evidence that immune
reconstitution inflammatory syndrome (IRIS) may develop. HIV progression versus the onset of IRIS are risks that must be weighed when treating HIV and cryptococcosis meningitis.

Cryptosporidiosis and isosporiasis

Cryptosporidiosis (crypto) and isosporiasis are both caused by protozoan parasites. These diseases are easily spread by contaminated food or water, or by direct contact with an infected person or animal. Both crypto and isosporiasis cause diarrhoea, nausea, vomiting and stomach cramps. In people with healthy immune systems, these symptoms do not last more than about 14 days. However, if the immune system is damaged then they can continue for a long time. Diarrhoea can interfere with the absorption of nutrients and this can lead to serious weight loss.

To confirm diagnosis of either disease, the stool is normally checked for parasites and their eggs. There is no cure for crypto, but antiretroviral therapy to restore immunity can effectively clear up the infection. For isosporiasis, TMP-SMX (trimethoprim-sulfamethoxazole) is often the preferred treatment.

Cytomegalovirus

Cytomegalovirus (CMV) is a virus that infects the whole body. Infection usually occurs in childhood yet the virus remains dormant unless the immune system is suppressed. It most commonly appears as retinitis, which causes blurred vision and can lead to blindness, and also as gastrointestinal disease. CMV can also affect other organs such as the lungs or liver, and is capable of causing fever, diarrhoea, nausea, pneumonia-like symptoms and dementia.

CMV infection may be treated with drugs such as ganciclovir, valganciclovir, cidofovir and forscarnet. Before the roll out of ARV, studies identified that up to 40% of AIDS patients aquired CMV. Access to ARV’s now deter the chances of infection as immune systems can be supported. It is recommended to initiate ART following anti-CMV treatment in order to reduce the chance of a relapse.

Herpes simplex and Herpes zoster

The usual symptoms of herpes simplex virus infection (HSV, which causes sores around the mouth and genitals) and herpes zoster virus infection (or varicella zoster virus (VZV), which causes chickenpox (varicella) and shingles (zoster)) are not life-threatening but can be extremely painful. Both viruses are also capable of causing retinitis and, less often, encephalitis (which can be life-threatening). Herpes Zoster is transmitted usually through the respiratory route, whereas Herpes Simplex Virus is transmitted through contact with secretions from an infected area.

Both herpes simplex and herpes zoster are usually diagnosed by simple examination of the affected area, and may be treated with drugs such as acyclovir, famciclovir and valacyclovir. One particular study found using acyclovir to treat herpes simplex in those living with HIV and not taking ARVs, modestly reduces the risk of HIV disease progression.³

Histoplasmosis

Histoplasmosis is a fungal infection that primarily affects the lungs but may also affect other organs. Infection occurs through inhalation of fungus spores. Symptoms can include fever, fatigue, weight loss and difficulty in breathing.
Disseminated histoplasmosis infection may be diagnosed using an antigen test, and can be fatal if left untreated. Treatment usually involves amphotericin B or itraconazole.

Kaposi's sarcoma

Kaposi's sarcoma on the skin of an AIDS patient

HIV-associated Kaposi's sarcoma causes dark blue lesions, which can occur in a variety of locations including the skin, mucous membranes, gastrointestinal tract, lungs or lymph nodes. The lesions usually appear early in the course of HIV infection.
Treatment depends on the lesions' symptoms and location. For local lesions, injection therapy with vinblastine has been used with some success. Radiotherapy can also be used, especially in hard-to reach sites such as the inner mouth, eyes, face and soles of the feet. For severe widespread disease, systemic chemotherapy is the preferred treatment.

Leishmaniasis

Leishmaniasis is transmitted by sandflies and possibly through sharing needles. The most serious of its four forms is visceral leishmaniasis (also know as kala azar) which is characterised by irregular bouts of fever, substantial weight loss, swelling of the spleen and liver and anaemia (occasionaly serious). In its more common forms, leishmaniasis can produce disfiguring lesions around the nose, mouth and throat, or skin ulcers leading to permanent scarring.
Treatment of leishmaniasis is with either a pentavalent antimony or liposomal amphotericin B in the case of visceral leishmaniasis. Sodium stibogluconate is used to treat cutaneous leishmaniasis. If left untreated, visceral leishmaniasis is usually fatal.

MAC

The germs of the mycobacterium avium complex (MAC) are related to the germ that causes tuberculosis. MAC disease generally affects multiple organs, and symptoms include fever, night sweats, weight loss, fatigue, diarrhoea and abdominal pain. It is not believed that person-to-person transmission occurs; the MAC organisms are present throughout the environment. Infection occurs through the respiratory or gastrointestinal tract, infecting individuals with severely inhibited immune systems.
MAC should be treated using at least two antimycobacterial drugs to prevent or delay the emergence of resistance. Such drugs include clarithromycin, azithromycin, ethambutol and rifabutin.

PCP

PCP is caused by a fungus, which was formerly called pneumocystis carinii but has now been renamed pneumocystis jirovecii. PCP is a frequent HIV associated opportunistic infection which occurred in 70%-80% of patients with AIDS prior to the widespread use of primary PCP prophylaxis and ART, which has led to a significant decline of cases. The symptoms are mainly pneumonia along with fever and respiratory symptoms such as dry cough, chest pain and dyspnoea (difficulty in breathing). Definitive diagnosis requires microscopy of bodily tissues or fluids.
Severe cases of PCP are initially treated with TMP-SMX or clindamycin and oral primaquine. Mild cases can be treated with oral TMP-SMX throughout. With both of these regimens, toxicity (notably allergic-type reactions) often requires changes in therapy.
Prevention of PCP is strongly recommended for HIV-infected persons with very weak immune systems wherever PCP is a significant health problem for HIV-infected persons, and also after their first episode of PCP. The preferred drug is usually TMP-SMX.

Toxoplasmosis

Toxoplasmosis (toxo) is caused by a protozoan found in uncooked meat and cat faeces. This microbe infects the brain and can cause raised intracranial pressure, which leads to headaches and vomiting. Other symptoms include confusion, motor weakness and fever. In the absence of treatment, disease progression results in seizures, stupour and coma. Disseminated toxo is less common, but can affect the eyes and cause pneumonia.
Definitive diagnosis of toxo requires radiographic testing (usually an MRI scan). The infection is treated with drugs such as pyrimethamine, sulfadiazine and clindamycin. Leucovorin may also be used to prevent the side-effects of pyrimethamine. Prophylaxis against toxo is through taking TMP-SMX.
Recommendations⁴ advise HIV-positive individuals to:

• Avoid ingestion of undercooked meat
• To wash hands after any contact with soil
• To avoid emptying cat litter trays, or to empty trays daily and wash hands thoroughly after every disposal.

Tuberculosis

Tuberculosis (TB) is a bacterial infection that primarily infects the lungs. Tuberculosis is the leading HIV-associated opportunistic disease in developing countries. For people who are dually infected with HIV and TB, the risk of developing active tuberculosis is 30-50 fold higher than for people infected with TB alone. And because mycobacterium can spread through the air, the increase in active TB cases among dually infected people means:

• more transmission of the TB germ
• more TB carriers
• more TB in the whole population.

Tuberculosis is harder to diagnose in HIV-positive people than in those who are uninfected. The diagnosis of TB is important because TB progresses faster in HIV-infected people. Also, TB in HIV-positive people is more likely to be fatal if undiagnosed or left untreated. TB occurs earlier in the course of HIV infection than many other opportunistic infections.

A proper combination of anti-TB drugs achieves both prevention and cure. Effective treatment quickly makes the individual non-contagious, which prevents further spread of the TB germ. The DOTS (directly observed short course) treatment strategy recommended by WHO treats TB in HIV-infected persons as effectively as it treats those without the virus. A complete cure takes 6 to 8 months and uses a combination of antibiotics. In addition to curing the individual, it also prevents further spread of the disease to others. This is why treating infectious cases of TB has important benefits for society as a whole.

Isoniazid preventive therapy is recommended as a health-preserving measure for HIV-infected persons at risk of TB, as well as for those with latent TB infection.

 

OPPORTUNISTIC INFECTIONS

• WHAT ARE OPPORTUNISTIC INFECTIONS?
• TESTING FOR OIs
• OIs AND AIDS
• WHAT ARE THE MOST COMMON OIs?
• PREVENTING OIs
• TREATING OIs

WHAT ARE OPPORTUNISTIC INFECTIONS?

In our bodies, we carry many germs – bacteria, protozoa, fungi, and viruses. When our immune system is working, it controls these germs. But when the immune system is weakened by HIV disease or by some medications, these germs can get out of control and cause health problems.
Infections that take advantage of weakness in the immune defenses are called “opportunistic”. The phrase “opportunistic infection” is often shortened to “OI”.

TESTING FOR OIs

You can be infected with an OI, and “test positive” for it, even though you don’t have the disease. For example, almost everyone with HIV tests positive for Cytomegalovirus (CMV). But it is very rare for CMV disease to develop unless the CD4 cell count drops below 50, a sign of serious damage to the immune system.
To see if you’re infected with an OI, your blood might be tested for antigens (pieces of the germ that causes the OI) or for antibodies (proteins made by the immune system to fight the germs). If the antigens are found, it means you?re infected. If the antibodies are found, you?ve been exposed to the infection. You may have been immunized against the infection, or your immune system may have ?cleared? the infection, or you may be infected. If you are infected with a germ that causes an OI, and if your CD4 cells are low enough to allow that OI to develop, your health care provider will look for signs of active disease. These are different for the different OIs.

OIs AND AIDS

People who aren’t HIV-infected can develop OIs if their immune systems are damaged. For example, many drugs used to treat cancer suppress the immune system. Some people who get cancer treatments can develop OIs.
HIV weakens the immune system so that opportunistic infections can develop. If you are HIV-infected and develop opportunistic infections, you might have AIDS.
In the US, the Center for Disease Control (CDC) is responsible for deciding who has AIDS. The CDC has developed a list of about 24 opportunistic infections. If you have HIV and one or more of these “official” OIs, then you have AIDS. The list is available at http://www.aidsmeds.com/lessons/StartHere8.htm.

WHAT ARE THE MOST COMMON OIs?

In the early years of the AIDS epidemic, OIs caused a lot of sickness and deaths. Once people started taking strong antiretroviral therapy (ART), however, a lot fewer people got OIs. It’s not clear how many people with HIV will get a specific OI.
In women, health problems in the vaginal area may be early signs of HIV. These can include pelvic inflammatory disease and bacterial vaginosis, among others. See fact sheet 610 for more information.
The most common OIs are listed here, along with the disease they usually cause, and the CD4 cell count when the disease becomes active:

• Candidiasis (Thrush) is a fungal infection of the mouth, throat, or vagina. CD4 cell range: can occur even with fairly high CD4 cells.
• Cytomegalovirus (CMV) is a viral infection that causes eye disease that can lead to blindness.CD4 cell range: under 50.
• Herpes simplex viruses can cause oral herpes (cold sores) or genital herpes. These are fairly common infections, but if you have HIV, the outbreaks can be much more frequent and more severe. They can occur at any CD4 cell count.
• Malaria is common in the developing world. It is more common and more severe in people with HIV infection.
• Mycobacterium avium complex (MAC or MAI) is a bacterial infection that can cause recurring fevers, general sick feelings, problems with digestion, and serious weight loss. CD4 cell range: under 75.
• Pneumocystis pneumonia (PCP) is a fungal infection that can cause a fatal pneumonia. CD4 cell range: under 200. Unfortunately this is still a fairly common OI in people who have not been tested or treated for HIV.
• Toxoplasmosis (Toxo) is a protozoal infection of the brain. T-cell range: under 100.
• Tuberculosis (TB) is a bacterial infection that attacks the lungs, and can cause meningitis. CD4 cell range: Everyone with HIV who tests positive for exposure to TB should be treated.

PREVENTING OIs

Most of the germs that cause OIs are quite common, and you may already be carrying several of these infections. You can reduce the risk of new infections by keeping clean and avoiding known sources of the germs that cause OIs.
Even if you’re infected with some OIs, you can take medications that will prevent the development of active disease. This is called prophylaxis. The best way to prevent OIs is to take strong ART. See Fact Sheet 403 for more information on ART.
The Fact Sheets for each OI have more information on avoiding infection or preventing the development of active disease.

TREATING OIs

For each OI, there are specific drugs, or combinations of drugs, that seem to work best. Refer to the Fact Sheets for each OI to learn more about how they are treated.
Strong antiretroviral drugs can allow a damaged immune system to recover and do a better job of fighting OIs. Fact Sheet 481 on Immune Restoration has more information on this topic.

Opportunistic Infections and Their Relationship to HIV/AIDS

People with healthy immune systems can be exposed to certain viruses, bacteria, or parasites and have no reaction to them—but people living with HIV/AIDS can face serious health threats from what are known as “opportunistic” infections (OIs). These infections are called “opportunistic” because they take advantage of your weakened immune system, and they can cause devastating illnesses.
OIs are signs of a declining immune system. Most life-threatening OIs occur when your CD4 count is below 200 cells/mm³. OIs are the most common cause of death for people with HIV/AIDS.
The CDC developed a list of more than 20 OIs that are considered AIDS-defining conditions—if you have HIV and one or more of these OIs, you will be diagnosed with AIDS, no matter what your CD4 count happens to be:

• Candidiasis of bronchi, trachea, esophagus, or lungs
• Invasive cervical cancer
• Coccidioidomycosis
• Cryptococcosis
• Cryptosporidiosis, chronic intestinal (greater than 1 month's duration)
• Cytomegalovirus disease (particularly CMV retinitis)
• Encephalopathy, HIV-related
• Herpes simplex: chronic ulcer(s) (greater than 1 month's duration); or bronchitis, pneumonitis, or esophagitis
• Histoplasmosis
• Isosporiasis, chronic intestinal (greater than 1 month's duration)
• Kaposi's sarcomav
• Lymphoma, multiple forms
• Mycobacterium avium complex
• Tuberculosis
• Pneumocystis carinii pneumonia
• Pneumonia, recurrent
• Progressive multifocal leukoencephalopathy
• Salmonella septicemia, recurrent
• Toxoplasmosis of brain
• Wasting syndrome due to HIV

Because they can be so dangerous to your health, it is essential that you understand the signs, symptoms, prevention, and management of OIs.

Can I Prevent Opportunistic Infections?

One of the goals of HIV treatment is to lower your risk of getting OIs. Antiretroviral therapy can help by increasing your number of CD4 cells, which will help protect you from OIs. You may also take medications used to prevent disease from occurring (this is known as prophylaxis).

The Basics of Opportunistic Infections

OIs can occur all over the body and be relatively localized (meaning they affect only one part of the body) or systemic or disseminated (meaning they spread to other parts of the body and other body systems). Whether and when you become susceptible to OIs is often related to your CD4 count.

• Greater than 500 cells/mm³
  • OPPORTUNISTIC INFECTIONS
    • In general, people with CD4 counts greater than 500 cells/mm³ are not at risk for opportunistic infections. For people with CD4 counts around 500, however, the daily fluctuations in CD4 cell levels can leave them vulnerable to minor infections, such as candidal vaginitis or yeast infections.
  • SYMPTOMS
    • SEE SYMPTOMS UNDER CANDIDIASIS
• 500 cells/mm³ to 200 cells/mm³
  • OPPORTUNISTIC INFECTIONS
    • Candidiasis (Thrush)
      This is a fungal infection that is normally seen in patients with CD4 counts in this range. It is treatable with antifungal medications. A trained provider can usually diagnose thrush with a visual examination.
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    • Kaposi’s Sarcoma (KS)
      KS is caused by Human Herpes Virus-8. Before the introduction of antiretroviral therapy, as many as 1 in 5 patients with AIDS had KS. It can cause lesions on the body and in the mouth. In addition, this virus can affect internal organs and disseminate to other parts of the body without any external signs. Treatment plans can include chemotherapy to shrink the lesions, as well as antiretroviral therapy to increase CD4 cell count. A diagnosis is typically made by inspecting a lesion and performing a direct biopsy on it.
  • SYMPTOMS
    • Oral Symptoms include:
      • White patches on gums, tongue or lining of the mouth
      • Pain in the mouth or throat
      • Difficulty Swallowing
      • Loss of Appetite
      
      Vaginal Symptoms Include:
      • Vaginal Irritation
      • Itching
      • Burning
      • Thick, white discharge
      
      Signs and Symptoms of KS can include:
      • Appearance of a purplish lesion on skin
      • Appearance of a purplish lesion in the mouth
      • Occasionally gastrointestinal complaints with disseminated KS
• 200 cells/mm³ to 100 cells/mm³
  • OPPORTUNISTIC INFECTIONS
    • Pnuemocystis Jirovecii (Carinii) Pneumonia (PCP)
      PCP is a fungal infection and is the OI that most often causes death in patients with HIV. It is treatable with antibiotic therapy and close monitoring. If necessary, prophylaxis is available for patients who are at risk for PCP, but who are not ready to start antiretroviral medication. Diagnosing PCP usually involves a hospital stay to ensure proper testing and treatment without complications. For more information, see CDC’s You Can Prevent PCP.
      
      Histoplasmosis and Coccidioidomycosis
      These are fungal infections that are found in many regions of the United States. They often present as severe, disseminated illnesses in patients with low CD4 counts. Diagnosis consists of blood tests and evaluation for possible exposures related to geographical areas. For more information, see CDC’s Histoplasmosis or Coccidiodomycosis.
      
      Progressive Multifocal Leukoencephalopathy (PML)
      PML is a severe neurological condition that is caused by the JC virus and typically occurs in patients with CD4 counts below 200. While there is no definitive treatment for this disease, it has been shown to be responsive to antiretroviral therapy. In some cases, the disease resolves without any treatment. For more information, see the National Institute of Neurological Disorders and Stroke’s Progressive Multifocal Leukoencephalopathy Information Page.
  • SYMPTOMS
    • Signs and Symptoms of PCP can include:
      • Shortness of Breath
      • Fever
      • Dry Cough
      • Chest Pain
      
      Signs and Symptoms of Histoplasmosis and Coccidioidomycosis can include:
      • Fever
      • Fatigue
      • Weight Loss
      • Cough
      • Chest pain
      • Shortness of Breath
      • Headache
      
      Signs and Symptoms of PML can include:
      • Dementia
      • Seizures
      • Difficulty Speaking
      • Confusion
      • Difficulty walking
• 100 cells/mm³ to 50 cells/mm³
  • OPPORTUNISTIC INFECTIONS
    • Toxoplasmosis
      Toxoplasmosis is caused by the parasite Toxoplasma gondii that can cause encephalitis and neurological disease in patients with low CD4 counts. The parasite is carried by cats, birds, and other animals and is also found in soil contaminated by cat feces and in meat, particularly pork. Toxoplasmosis is treatable with aggressive therapy, and prophylaxis is recommended for patients with low CD4 counts (usually less than 200). Diagnosis of this condition often requires imaging studies (CT or MRI) of the brain and a blood test. For more information, see CDC’s Toxoplasmosis and You Can Prevent Toxo.
      
      Cryptosporidiosis
      Cryptosporidiosis is a diarrheal disease caused by the protozoa Cryptosporidium, and it can become chronic for people with low CD4 counts. Symptoms include abdominal cramps and severe chronic diarrhea. Infection with this parasite can occur through: swallowing water that has been contaminated with fecal material (in swimming pools, lakes, or public water supplies); eating uncooked food (like oysters) that are infected; or by person-to-person transmission, including changing diapers or exposure to feces during sexual contact. Treatment and antiretroviral therapy are important. For more information, see CDC’s Cryptosporidiosis and You Can Prevent Cryptosporidiosis.
      
      Cryptococcal Infection or Cryptococcosis
      Cryptococcal infection is caused by a fungus thattypically enters the body through the lungs and can spread to the brain, causing cryptococcal meningitis. In some cases, it can also affect the skin, skeletal system, and urinary tract. This can be a very deadly infection if not caught and properly treated with antifungal medication. Although this infection is found primarily in the central nervous system, it can disseminate to other parts of the body, especially when a person has a CD4 count of less than 50. For more information, see CDC’s Cryptococcus (Cryptococcosis).
  • SYMPTOMS
    • Signs and Symptoms of Toxoplasmosis can include:
      • Headache
      • Confusion
      • Motor Weakness
      • Fever
      • Seizures
      
      Signs and Symptoms of Cryptosporidiosis can include:
      • Chronic Watery Diarrhea
      • Stomach cramps
      • Weight loss
      • Nausea
      • Vomiting
      
      Signs and Symptoms of Cryptococcal Meningitis include:
      • Fever
      • Fatigue
      • Headache
      • Neck Stiffness
      • Some patients can have memory loss or mood changes
• 50-100 Cells/mm³
  • OPPORTUNISTIC INFECTIONS
    • Cytomegalovirus (CMV)
      CMV is an extremely common virus that is present in all parts of the world. It is estimated that a majority of the population have had CMV by the time they are 40 years-old. CMV can be transmitted by saliva, blood, semen and other bodily fluids. It can cause mild illnesses when first contracted and many people may never have symptoms. However, it does not leave the body when someone is infected with CMV. In patients with HIV and low CD4 counts it can cause infections in the eye and gastrointestinal system. For more information, see CDC's You can prevent CMV.
  • SYMPTOMS
    • Signs and Symptoms of CMV:
      • Sore Throat
      • Swollen Glands
      • Fatigue
      • Fevers
      
      In people with low CD4 counts it can cause:
      • Blurred vision (if there is CMV infection is in the eye)
      • Painful Swallowing
      • Diarrhea
      • Abdominal Pain
• Less than 50 Cells/mm³
  • OPPORTUNISTIC INFECTIONS
    • Mycobaterium Aviam Complex (MAC)
      MAC is a type of bacteria that can be found in soil, water, and many places in the environment. These bacteria can cause disease in people with HIV and CD4 Counts less that 50. The bacteria can infect the lungs or the intestines, or in some cases, can become “disseminated”. This means that it can spread to the blood stream and other parts of the body. If this occurs, it can be a life threatening infection. If a persons CD4 count is below 50, then medications are available to prevent this infection from occurring. For more information, see CDC's You can prevent MAC.
  • SYMPTOMS
    • Signs and Symptoms of MAC:
      • Fevers
      • Night sweats
      • Abdominal Pain
      • Fatigue
      • Diarrhea