Fever and confusion in a patient with HIV - Wednesday Apr 4, 2012

Thank you Dr. P. Bunce for hosting today’s morning report, and to team 5 for bringing the case.

Today, we discussed a case of a patient with HIV who presented to the Emergency Department with a 1-day history of fever and confusion.

There were 3 learning points that Dr. Bunce made today.

First is the differential diagnosis of confusion (or any altered level of consciousness) can be remembered by the mnemonics DIMS.  It stands for Drugs (prescribed, over the counter, illicit, recreational and intoxication or withdrawal), Infection (can be CNS or systemic), Metabolic (can be organ dysfunction [hepatic encephalopathy, uremic encephalopathy, hypercapnia], electrolytes, endocrine (thyroid, glucose, adrenal), and Structural (which has its own differential such as bleeding, abscess, tumour, stroke, vasculitis, etc…).  Seizure is sometimes on the differential diagnosis depending on the presentation.

The second learning point is that for any patient with HIV presenting to the Emergency Department, it is very important to know these features about their HIV as it changes the differential diagnosis:  what treatment (if any) they are on and their adherence to the medications, HIV related complications (including opportunistic infections, cancers, cardiac, renal dysfunction), most recent CD4 count, the name of their HIV doctor.  It is important to contact that doctor on the next working day.

Third learning point is HIV patients should not be having unprotected sex, and that acquisition of sexual transmitted infection should ring an alarm bell.

During the discussion of the case, we also talked about that pneumococcal pneumonia is still common among HIV patients.  Cryptococcal antigen can be sent in the CSF to rule out cryptococcal meningitis.  Bacterial meningitis should be treated with high dose ceftriaxone, vancomycin, and ampicillin (for listeria) as these drugs have high CNS penetrance.

You can read more about acute bacterial meningitis here.