Cryptococcal Antigen Screening and Missed Opportunities for Earlier Diagnosis Among People With HIV and Poor Virologic Control in the Bronx, NY.

Background: There is no established cryptococcal antigen (CrAg) screening guideline for people with HIV who are antiretroviral therapy experienced but have poor virologic control. We assessed factors associated with CrAg screening and describe missed opportunities for earlier testing.

Setting: Ambulatory clinics affiliated with Montefiore Medical Center, Bronx, NY.

Methods: This was a retrospective chart review of CrAg screening among asymptomatic people with HIV with absolute CD4 counts 200 cells/mm 3 and HIV viral loads (VLs) > 200 copies/mL receiving HIV care from 2015 to 2020. We used Cox proportional hazards regression to identify predictors of screening, including longitudinal CD4 count and HIV VL as time-varying covariables. Among cases of diagnosed cryptococcosis, we assessed for opportunities for earlier diagnosis.

Results: Screening CrAg was performed in 2.9% of 2201 individuals meeting the inclusion criteria. Compared with those not screened, those who were screened had a shorter duration of HIV infection (0.09 vs. 5.1 years; P = 0.001) and lower absolute CD4 counts (12 vs. 24 cells/mm 3 ; P < 0.0001). In a multivariable model stratified by median HIV duration, CD4 < 100 [hazard ratio (HR), 7.07; 95% confidence interval (CI): 2.43 to 20.6], VL > 10,000 (HR, 15.0; 95% CI: 4.16 to 54.0), and a shorter duration of HIV infection (HR, 0.60; 95% CI: 0.42 to 0.86) were associated with screening for those with HIV < 5 years. Among those diagnosed with cryptococcosis (n = 14), 6 individuals had an ambulatory visit in the preceding 6 months but did not undergo screening.

Conclusion: CrAg screening was infrequently performed in this at-risk population. Those with a longer duration of HIV infection were less likely to undergo CrAg screening, highlighting potential missed opportunities for earlier diagnosis.