Human Immunodeficiency Virus / AIDS Infections

Overview: Human immunodeficiency virus (HIV) is a retrovirus that infects primarily CD4+ T helper cells. The subsequent depletion of these cells, vital to immunologic competence, causes decreased protection against opportunistic infections. AIDS: when the CD4+ T cell counts fall below 200 cells/mm3 or opportunistic infections occur. Among HIV-infected men in all age groups, 68% identified their risk behavior as men… Read more »

Legionnaire’s Disease

Caused by Legionella pneumophila Symptoms Fever greater than 40 º C (>102 º F) with chills Cough (Dry or productive) Pleuritic chest pain Mental status changes with headache Diarrhea (watery) with nausea, vomiting, and/or abdominal pain Myalgias & arthralgias Physical Exam Bradycardia (look for this . . . with fever, tachypnea, and change in mental status, they should… Read more »

Argyll Robertson Pupil

Argyll Robertson pupils (“AR pupils” or colloquially as”Prostitute’s Pupil”) are bilateral small pupils that constrict when the patient focuses on a near object (they “accommodate”), but do not constrict when exposed to bright light (they do not “react” to light). They are a highly specific sign of neurosyphilis. 


Meningitis is a bacterial infection of the membranes covering the brain and spinal cord (meninges). Infections of the CNS can be divided into 2 broad categories: those primarily involving the meninges (meningitis) and those primarily confined to the parenchyma (encephalitis). Viral meningitis occurs more often than bacterial meningitis, and is milder. It usually occurs in the late summer… Read more »


Gonorrhea is an infection caused by a sexually transmitted bacterium that can infect both males and females. Gonorrhea most often affects the urethra, rectum or throat. In females, gonorrhea can also infect the cervix. Gonorrhea is most commonly spread during sex, but babies can be infected during childbirth. Gonococcemia is defined as the presence of N gonorrhoeae in… Read more »