acute retroviral syndrome; acute HIV1 infection

Etiology

• acute HIV1 infection

Pathology

• high levels of HIV1 viral load in the absence of HIV1 Ab
• immunosuppression is generally not present

Clinical manifestations

• patients may be asymptomatic
• flu-like or mononucleosis-like illness & exanthem in 40-90% of patients with acute HIV infection
  • fever (96%)
  • arthralgias & arthritis (54% combined with myalgia)
  • myalgias & myositis
  • headache (32%)
  • lymphadenopathy (74%)
    • posterior cervical lymphadenopathy
  • exudative pharyngitis (70%)
  • hepatosplenomegaly (27%)
  • meningitis & encephalitis
  • vasculitis
  • rash (exanthem) (70%)
    • asymptomatic erythematous macules & small papules over the upper trunk, face, proximal extremities
  • cough
  • diarrhea (32%)
  • nausea/vomiting (27%)
  • weight loss (13%)
  • thrush (12%)
  • oral aphthous ulcers
  • other neurologic manifestations (12%)
    • peripheral neuropathy
    • facial palsy
    • Guillain-Barre syndrome
    • brachial neuritis
    • cognitive impairment
    • psychosis
• time course of symptoms
  • generally occurs from 2-6 weeks after exposure
  • occurs 10-21 days before seroconversion
  • generally resolves without therapy in 7-10 days
  • most patients are symptomatic, but symptoms are non-specific & self-limited
• a longer duration of symptoms associated with seroconversion generally results in a more rapid progression to AIDS
• exanthem may be morbilliform or pityriasis rosea-like, most prominent on the trunk & face
• the exanthem is self-limited & often goes undiagnosed
• oral ulceration (aphthous stomatitis), oropharyngeal candidiasis or erosive esophagitis may occur
• reactivation of orolabial Herpes simplex

Laboratory

• quantitative HIV1 RNA levels
  • high levels of HIV1 RNA (500,000- 21 million copies/mL) are detected in plasma before detection of specific HIV1 antibodies or HIV1 p24 antigen
  • HIV1 p24 antigen is generally positive just after onset of symptoms or seroconversion, before development of antibodies
  • the high level of viremia decreases 100-10,000 fold coincident with development of the specific anti-HIV1 humoral immune response
    • cytotoxic T-cells may be responsible for this decline in HIV1 viral load
• HIV antigen/antibody combination test may be a useful screening tool (detect HIV1 p24 antigen)
• specific HIV1 antibodies* are not detectable until 4-12 weeks after initial infection
  • HIV1 ELISA for antibody to HIV1 is negative
  • confirmatory HIV1 Western blot is negative
  • HIV1/HIV2 antibody differentiation assay may be negative
• complete blood count may be normal
• comprehensive metabolic panel, including serum electrolytes, serum protein, liver function tests, renal function tests may be normal
• serologic tests for syphilis negative
• blood cultures & urine cultures show no growth

Radiology

• chest X-ray normal

Complications

• malignancy may be present at onset of early in HIV1 infection
  • spontaneous tumor lysis syndrome of Burkitt lymphoma

Differential diagnosis

• infectious mononucleosis
  • EBV rarely develops in middle age
  • meningitis uncommon
• ehrlichiosis:
  • leukopenia, lymphopenia, thrombocytopenia
  • elevated serum trasaminases
  • CSF pleocytosis rare
• typhoid fever
  • GI symptoms (constipation early, then diarrhea)
  • diffuse maculopapular rash & aseptic meningitis rare
  • blood cultures positive for Salmonella typhi
• Mycobacterium avium complex
  • abdominal pain, diarrhea, weight loss, anemia

Management

• early highly-active antiretroviral therapy (HAART) may favorably alter the course of infection

More general terms

• syndrome
• viral infection

Additional terms

• retroviral infection
• Retroviridae (retrovirus)