Acute HIV infection
Encyclopedia
Acute HIV infection or primary HIV infection (also known as "Acute seroconversion syndrome") is the second stage of HIV
infection. It occurs after the incubation stage, before the latency stage and the potential AIDS
succeeding the latency stage.
, lymphadenopathy
, pharyngitis
, generalized rash
of maculopapular type, myalgia
, malaise
, mouth and esophageal sores, and may also include, but less commonly, headache
, nausea
and vomiting
, enlarged liver/spleen, weight loss
, thrush
, and neurological symptoms. Infected individuals may experience all, some, or none of these symptoms. The acute illness can last between a few days and 10 weeks, though usually less than 14 days.
In some very rare cases, about 10 patients from 1989 to date, a bilateral facial palsy
has been associated with acute HIV-1 infection.
Because of the nonspecific nature of these symptoms, they are often not recognized as signs of HIV infection. Even if patients go to their doctors or a hospital, they will often be misdiagnosed as having one of the more common infectious diseases with the same symptoms. Consequently, these primary symptoms are not used to diagnose HIV infection as they do not develop in all cases and because many are caused by other more common diseases. However, recognizing the syndrome can be important because the patient is much more infectious during this period.
These nonspecific symptoms can also be symptoms of other infections; consequently, having these symptoms does not reliably indicate the presence of HIV.
, which kill HIV-infected cells, and subsequently with antibody production, or seroconversion
. The CD8+ T cell response is thought to be important in controlling virus levels, which peak and then decline, as the CD4+ T cell counts rebound to around 800 cells per mL (the normal value is 1200 cells per mL ). A good CD8+ T cell response has been linked to slower disease progression and a better prognosis, though it does not eliminate the virus.
A strong immune defense reduces the number of viral particles in the blood stream, marking the end of the acute HIV infection and the start of the infection's clinical latency
stage, which, in turn, may be succeeded by true AIDS
.
HIV
Human immunodeficiency virus is a lentivirus that causes acquired immunodeficiency syndrome , a condition in humans in which progressive failure of the immune system allows life-threatening opportunistic infections and cancers to thrive...
infection. It occurs after the incubation stage, before the latency stage and the potential AIDS
AIDS
Acquired immune deficiency syndrome or acquired immunodeficiency syndrome is a disease of the human immune system caused by the human immunodeficiency virus...
succeeding the latency stage.
Symptoms
During this period (usually 2–4 weeks post-exposure) an individual may develop influenza or mononucleosis-like symptoms, most commonly feverFever
Fever is a common medical sign characterized by an elevation of temperature above the normal range of due to an increase in the body temperature regulatory set-point. This increase in set-point triggers increased muscle tone and shivering.As a person's temperature increases, there is, in...
, lymphadenopathy
Lymphadenopathy
Lymphadenopathy is a term meaning "disease of the lymph nodes." It is, however, almost synonymously used with "swollen/enlarged lymph nodes". It could be due to infection, auto-immune disease, or malignancy....
, pharyngitis
Pharyngitis
Pharyngitis is an inflammation of the throat or pharynx. In most cases it is quite painful, and is the most common cause of a sore throat.Like many types of inflammation, pharyngitis can be acute – characterized by a rapid onset and typically a relatively short course – or chronic....
, generalized rash
Rash
A rash is a change of the skin which affects its color, appearance or texture. A rash may be localized in one part of the body, or affect all the skin. Rashes may cause the skin to change color, itch, become warm, bumpy, chapped, dry, cracked or blistered, swell and may be painful. The causes, and...
of maculopapular type, myalgia
Myalgia
Myalgia means "muscle pain" and is a symptom of many diseases and disorders. The most common causes are the overuse or over-stretching of a muscle or group of muscles. Myalgia without a traumatic history is often due to viral infections...
, malaise
Malaise
Malaise is a feeling of general discomfort or uneasiness, of being "out of sorts", often the first indication of an infection or other disease. Malaise is often defined in medicinal research as a "general feeling of being unwell"...
, mouth and esophageal sores, and may also include, but less commonly, headache
Headache
A headache or cephalalgia is pain anywhere in the region of the head or neck. It can be a symptom of a number of different conditions of the head and neck. The brain tissue itself is not sensitive to pain because it lacks pain receptors. Rather, the pain is caused by disturbance of the...
, nausea
Nausea
Nausea , is a sensation of unease and discomfort in the upper stomach with an involuntary urge to vomit. It often, but not always, precedes vomiting...
and vomiting
Vomiting
Vomiting is the forceful expulsion of the contents of one's stomach through the mouth and sometimes the nose...
, enlarged liver/spleen, weight loss
Weight loss
Weight loss, in the context of medicine, health or physical fitness, is a reduction of the total body mass, due to a mean loss of fluid, body fat or adipose tissue and/or lean mass, namely bone mineral deposits, muscle, tendon and other connective tissue...
, thrush
Candidiasis
Thrush redirects here. For the hoof infection see Thrush .Candidiasis or thrush is a fungal infection of any of the Candida species , of which Candida albicans is the most common...
, and neurological symptoms. Infected individuals may experience all, some, or none of these symptoms. The acute illness can last between a few days and 10 weeks, though usually less than 14 days.
In some very rare cases, about 10 patients from 1989 to date, a bilateral facial palsy
Bell's palsy
Bell's palsy is a form of facial paralysis resulting from a dysfunction of the cranial nerve VII that results in the inability to control facial muscles on the affected side. Several conditions can cause facial paralysis, e.g., brain tumor, stroke, and Lyme disease. However, if no specific cause...
has been associated with acute HIV-1 infection.
Because of the nonspecific nature of these symptoms, they are often not recognized as signs of HIV infection. Even if patients go to their doctors or a hospital, they will often be misdiagnosed as having one of the more common infectious diseases with the same symptoms. Consequently, these primary symptoms are not used to diagnose HIV infection as they do not develop in all cases and because many are caused by other more common diseases. However, recognizing the syndrome can be important because the patient is much more infectious during this period.
These nonspecific symptoms can also be symptoms of other infections; consequently, having these symptoms does not reliably indicate the presence of HIV.
| sensitivity | specificity | |
|---|---|---|
| Fever | 88% | 50% |
| Malaise | 73% | 58% |
| Myalgia | 60% | 74% |
| Rash | 58% | 79% |
| Headache | 55% | 56% |
| Night sweats | 50% | 68% |
| Sore throat | 43% | 51% |
| Lymphadenopathy | 38% | 71% |
| Arthralgia | 28% | 87% |
| Nasal congestion | 18% | 62% |
Cause
Acute HIV infection is a period of rapid viral replication that immediately follows the individual's exposure to HIV leading to an abundance of virus in the peripheral blood with levels of HIV commonly approaching several million viruses per mL. This response is accompanied by a marked drop in the numbers of circulating CD4+ T cells. This acute viremia is associated in virtually all patients with the activation of CD8+ T cellsCytotoxic T cell
A cytotoxic T cell belongs to a sub-group of T lymphocytes that are capable of inducing the death of infected somatic or tumor cells; they kill cells that are infected with viruses , or are otherwise damaged or...
, which kill HIV-infected cells, and subsequently with antibody production, or seroconversion
Seroconversion
Seroconversion is the development of detectable specific antibodies to microorganisms in the blood serum as a result of infection or immunization. Serology is used to determine antibody positivity...
. The CD8+ T cell response is thought to be important in controlling virus levels, which peak and then decline, as the CD4+ T cell counts rebound to around 800 cells per mL (the normal value is 1200 cells per mL ). A good CD8+ T cell response has been linked to slower disease progression and a better prognosis, though it does not eliminate the virus.
A strong immune defense reduces the number of viral particles in the blood stream, marking the end of the acute HIV infection and the start of the infection's clinical latency
Incubation period
Incubation period is the time elapsed between exposure to a pathogenic organism, a chemical or radiation, and when symptoms and signs are first apparent...
stage, which, in turn, may be succeeded by true AIDS
AIDS
Acquired immune deficiency syndrome or acquired immunodeficiency syndrome is a disease of the human immune system caused by the human immunodeficiency virus...
.