Cryptococcosis in liver and kidney transplant recipients receiving anti-thymocyte globulin or alemtuzumab

Managing cryptococcosis in the immunocompromised host

PURPOSE OF REVIEW

Expanding access to antiretroviral treatment has dramatically improved the long-term prognosis of patients with HIV-associated cryptococcal disease who survive the acute infection. However, the incidence and acute mortality of HIV-associated cryptococcal meningitis remain high. In this context, this review summarizes urgently needed recent work aimed at improving the acute management of cryptococcal infection in immunocompromised hosts.

RECENT FINDINGS

Studies have started to optimize antifungal regimens and address the complications of raised cerebrospinal fluid pressure and cryptococcal immune reconstitution syndrome. Amphotericin B at 1 mg/kg per day has been shown to be more rapidly fungicidal than the standard dose of 0.7 mg/kg per day, and new data support the importance of combination therapy with flucytosine. Amphotericin B and fluconazole at 800 mg is an alternative combination that appears superior to amphotericin B alone. At a dosage of 400 mg per day, fluconazole alone is much less rapidly fungicidal than amphotericin B and is associated with the development of secondary resistance.

SUMMARY

Recent findings support the use of rapidly fungicidal initial antifungal therapy with amphotericin B-based combination treatment. Where amphotericin B treatment is not yet feasible, studies are needed to optimize oral regimens. Based on accumulating data on rate of clearance of infection, the most promising new regimens in terms of fungicidal activity and safety could be selected for clinical endpoint trials.

Cryptococcosis in solid organ transplant recipients: current state of the science

Cryptococcosis remains a significant opportunistic infection in solid organ transplant recipients. Disease presentation and outcomes may be affected by, among other factors, the use of calcineurin inhibitor immunosuppressive agents. It is being increasingly recognized that rapid reversal of immunosuppression in transplant recipients treated for cryptococcosis incurs the risk of immune reconstitution inflammatory syndrome, which resembles worsening disease or relapse. This review summarizes the current state of knowledge regarding cryptococcosis in transplant recipients and highlights areas where future investigations are needed to further optimize outcomes for these patients.

Pulmonary cryptococcosis in solid organ transplant recipients: clinical relevance of serum cryptococcal antigen

BACKGROUND

The role of serum cryptococcal antigen in the diagnosis and determinants of antigen positivity in solid organ transplant (SOT) recipients with pulmonary cryptococcosis has not been fully defined.

METHODS

We conducted a prospective, multicenter study of SOT recipients with pulmonary cryptococcosis during 1999-2006.

RESULTS

Forty (83%) of 48 patients with pulmonary cryptococcosis tested positive for cryptococcal antigen. Patients with concomitant extrapulmonary disease were more likely to have a positive antigen test result (P=.018), and antigen titers were higher in patients with extrapulmonary disease (P=.003) or fungemia (P=.045). Patients with single nodules were less likely to have a positive antigen test result than were those with all other radiographic presentations (P=.053). Among patients with isolated pulmonary cryptococcosis, lung transplant recipients were less likely to have positive cryptococcal antigen test results than were recipients of other types of SOT (P=.003). In all, 38% of the patients were asymptomatic or had pulmonary cryptococcosis detected as an incidental finding. Nodular densities or mass lesions were more likely to present as asymptomatic or incidentally detected pulmonary cryptococcosis than as pleural effusions and infiltrates (P=.008).

CONCLUSIONS

A positive serum cryptococcal antigen test result in SOT recipients with pulmonary cryptococcosis appears to reflect extrapulmonary or more advanced radiographic disease.