Clinical Pearls & Morning Reports
Patients with acute HIV infection often have a transient but clinically significant decrease in the CD4+ T-lymphocyte count, sometimes to a level of less than 200 per microliter, which can lead to complication by opportunistic infections such as mucocutaneous candidiasis, pneumocystis pneumonia, and reactivation of tuberculosis. Read the NEJM Case Records of the Massachusetts General Hospital here.
Q: Describe findings typical of acute tuberculous meningitis on cerebrospinal fluid analysis.
A: In patients with acute tuberculous meningitis, cerebrospinal fluid analysis would show neutrophilic pleocytosis, a substantially elevated protein level, and a low glucose level, with a mildly elevated opening pressure.
Q: What is the average incubation period for acute hepatitis A, B, and C?
A: The average incubation period for acute hepatitis A, B, and C is 28 days, 90 days, and 14 to 84 days, respectively.
A: Although the majority of new diagnoses of HIV infection in the United States are reported in cisgender men who have sex with men, 19% of new diagnoses of HIV infection in the United States in 2018 were reported in cisgender women, with nearly 85% of those attributed to heterosexual contact. New incident cases of HIV infection were seen in adults and seniors; 60% of all incident cases in cisgender women occurred in those older than 35 years of age.
A: To establish the diagnosis of acute HIV infection, it is important to understand the temporal appearance of HIV-specific biomarkers. The time between exposure to HIV and the development of viremia, called the eclipse period, usually lasts 7 to 10 days. During the eclipse period, no HIV diagnostic tests will be positive. Around 10 days after exposure, high-level viremia can be detected on an HIV nucleic acid assay and symptoms of acute infection typically develop, although a small group of patients remain asymptomatic. Approximately 1 week later (17 to 20 days after exposure), HIV p24 antigen can be detected on a standard HIV antigen and antibody assay of the blood. Around 21 to 25 days after exposure, HIV-1 or HIV-2 antibodies can be detected. The time between the first detection of viremia on a nucleic acid assay and the first detection of HIV-specific antibodies (seroconversion) is called the window period.