Infectious Disease Consult Is a Strong Predictor of Reduced Mortality in Cryptococcosis

Background: An infectious disease (ID) consultation is often obtained to treat patients with cryptococcosis due to the rare and complex nature of the disease.   We examined if an ID consult affected outcomes in HIV-negative patients with cryptococcosis.

Methods: We assembled a retrospective cohort of 147 consecutive cases of cryptococcosis in patients without HIV from 2002 to 2015 in our academic tertiary care hospital.  We collected data on comorbidities, predisposing factors, extent of infection, survival and ID consult.  Patients who died within 24 hours of diagnosis did not have an opportunity to receive an ID consult and were excluded.  Survival analysis was performed with Cox Regression with censoring at 90 days, as subsequent mortality was less likely to be related to cryptococcus.

Results: One hundred (68.0%) of the patients with cryptococcal infection received an ID consult; 47 (32.0%) did not. Underlying comorbidities were evenly distributed between patients with and without an ID consult.  Patients with an ID consult had a more extensive disease as demonstrated by higher proportion of dissemination, and higher cryptococcal antigen levels. The ID consult group had lower 90-day mortality compared to patients without an ID consult (27.0% vs 44.7%, p<0.001), with an adjusted hazard ratio of mortality for those patients not receiving an ID consult of 4.13 (95% CI: 2.24, 7.63, p<0.001) (Fig 1).  Patient management differed significantly:  the ID consult group was more likely to receive an indicated lumbar puncture (85.9% vs 32.4%, p<0.001), and more likely to be treated with amphotericin B (AmB) (87.1% vs 24.4%, p<0.001) and flucytosine (5-FC) (57.0% vs 15.6%, p<0.001) when indicated. The duration of therapy with AmB (17.0 vs 8.7 days, p=0.05) and 5-FC (11.2 vs 0.6 days, p<0.001) was longer in the ID consult group.

Conclusion: Patients who received an ID consult were significantly less likely to die, and were more likely to be managed according to current evidence-based practice as established by randomized controlled trials and recommended in published guidelines. These data suggest that an ID consult should be an integral part of clinical care of patients with cryptococcosis.