IRIS

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Spring his here! The daffodils, cherry blossoms, and irises have blossomed.  Though today we discussed a not-so-good type of IRIS... Immune Reconstitution Inflammatory Syndrome.  Here are 3 learning points we discussed...

1.  Though there is not a universal agreed upon definition for IRIS, most of the following criteria should be present to diagnose IRIS:
-AIDS with a nadir CD4 <100 (Unless TB - CD4 often >200)
-Positive virologic and immunological response to antiretroviral therapy
-Ruled out other potential etiologies (i.e. drug resistant infection, bacterial superinfection, drug allergy, non-compliance, reduced drug levels 2/2 malapsorption or drug-drug interaction)
-Evidence of inflammation
-Temporal relationship between ART initiation and illness (anywhere from 1 week to 5 months after ART)

2.  If a concomitant infection is diagnosed at the time of HIV diagnosis (particularly TB or meningitis), it is important to start therapy for the alternative infection at least 2 weeks before ART initiation.

3. In evaluation for TB enteritis, abdominal lymphadenopathy (hypodense centers representing caseous liquefacation) is a common finding, which can be detected by CT or ultrasound.  On imaging, concentric mural thickening of the ileocecal region can also be seen.