Coccidioidomycosis in solid organ transplant recipients

Outcomes of Coccidioides Seropositive Solid Organ Transplant Recipients After Self-discontinuation of Antifungal Prophylaxis: The EIA-IgM-only Conundrum

BACKGROUND

Solid organ transplant recipients are at risk of severe coccidioidomycosis and are given prophylaxis to mitigate the risk. Patients with seropositive testing typically receive lifelong prophylaxis; currently, this prophylaxis strategy includes patients who are positive only for IgM by enzyme immunoassay (EIA-IgM-only), although this result may be falsely positive.

METHODS

We conducted a retrospective study at a large-volume transplant center in an endemic coccidioidomycosis region to compare outcomes of non-lung transplant recipients who were seropositive for Coccidioides but discontinued prophylaxis (case patients) to outcomes of patients who continued prophylaxis (controls).

RESULTS

No case or control patients developed active coccidioidomycosis during the follow-up period. Before transplant, 62 of 77 case patients (80.5%) had a single positive serologic test, of whom 27 of 62 were EIA-IgM-only positive (43.5%). In contrast, 57 of 77 controls (74.0%) had a single seropositive result (16/57 [28.1%] were EIA-IgM-only). The single EIA-IgM-only result was classified as falsely positive by infectious disease consultants in 20 of 43 patients (46.5%) compared with all other Coccidioides serologic results (13/111 [11.7%], P < 0.001). Lifetime antifungal prophylaxis was felt to be unnecessary for 28 of 43 patients (65.1%) who were EIA-IgM-only versus 31 of 111 patients (27.9%) with other serologic results (P < 0.001).

CONCLUSIONS

For patients repeatedly positive for EIA-IgM-only and no evidence of seroconversion, compatible clinical illness, or radiographic findings, discontinuing antifungal prophylaxis may be reasonable after the first posttransplant year.

Controlling infections in hospitalized pretransplant candidates

PURPOSE OF REVIEW

Infections in hospitalized patients awaiting solid organ transplantation can pose complicated diagnostic and therapeutic challenges. Goals of management include stabilizing the patient, treating or controlling infections, and decreasing the risk of reactivation of infection after transplant.

RECENT FINDINGS

Groups such as The Organ Procurement and Transplantation Network, American Society of Transplantation Infectious Diseases Community of Practice and the European Society of Clinical Microbiology and Infectious Diseases have updated their guidelines on screening and treatment of infection in transplant candidates. There are also recent developments in therapeutic options for tuberculosis, COVID-19, Clostridioides difficile colitis, bloodstream infections, and other common infections.

SUMMARY

Ideally, antimicrobial therapy should be complete prior to transplantation. In situations in which completion of therapy prior to transplant is not feasible, therapy may need to be prolonged or modified. In most situations, infections can be managed similarly to the general population, although some infections, particularly fungal and mycobacterial, require a different management approach. We review disease- and organ-specific management.

Invasive fungal infections in liver diseases

Patients with liver diseases, including decompensated cirrhosis, alcohol-associated hepatitis, and liver transplant recipients are at increased risk of acquiring invasive fungal infections (IFIs). These infections carry high morbidity and mortality. Multiple factors, including host immune dysfunction, barrier failures, malnutrition, and microbiome alterations, increase the risk of developing IFI. Candida remains the most common fungal pathogen causing IFI. However, other pathogens, including Aspergillus, Cryptococcus, Pneumocystis, and endemic mycoses, are being increasingly recognized. The diagnosis of IFIs can be ascertained by the direct observation or isolation of the pathogen (culture, histopathology, and cytopathology) or by detecting antigens, antibodies, or nucleic acid. Here, we provide an update on the epidemiology, pathogenesis, diagnosis, and management of IFI in patients with liver disease and liver transplantation.

Fungal Infections in Liver Transplant Recipients

Invasive fungal infections (IFIs) are one of the most feared complications associated with liver transplantation, with high rates of morbidity and mortality. We discuss the most common invasive fungal infections in the setting of liver transplant, including Candida, Aspergillus, and Cryptococcal infections, and some less frequent but devastating mold infections. Further, we evaluate the use of prophylaxis to prevent invasive fungal infection in this population as a promising mechanism to reduce risks to patients after liver transplant.

Fungal pneumonia in kidney transplant recipients

Fungal pneumonia is a dreaded complication encountered after kidney transplantation, complicated by increased mortality and often associated with graft failure. Diagnosis can be challenging because the clinical presentation is non-specific and diagnostic tools have limited sensitivity and specificity in kidney transplant recipients and must be interpreted in the context of the clinical setting. Management is difficult due to the increased risk of dissemination and severity, multiple comorbidities, drug interactions and reduced immunosuppression which should be applied as an important adjunct to therapy. This review will focus on the main causes of fungal pneumonia in kidney transplant recipients including Pneumocystis, Aspergillus, Cryptococcus, mucormycetes and Histoplasma. Epidemiology, clinical presentation, laboratory and radiographic features, specific characteristics will be discussed with an update on diagnostic procedures and treatment.

Coccidioidomycosis in Allogeneic Stem Cell Transplant Recipients: Case Series and Review of the Literature

Coccidioides is an endemic fungus of the Southwest United States that causes the disease coccidioidomycosis. Immunocompromised persons are at increased risk for severe infection and dissemination. One such population is allogeneic bone marrow transplant (allo-HCT) recipients, but accounts of coccidioidal infection in these patients have rarely been documented. We present two cases of Coccidioides in allo-HCT recipients with good outcomes: one patient who developed pulmonary coccidioidomycosis in the late post-engraftment phase and another with known controlled disseminated infection at the time of transplant. A review of the literature identified 19 allo-HCT recipients with coccidioidomycosis. Due to the limited published literature, no guidelines have yet been established regarding optimal prophylaxis and treatment of Coccidioides infection in allo-HCT recipients. Candidates for transplantation should undergo a rigorous pre-transplant assessment to identify evidence of prior or active coccidioidomycosis. In our experience, patients who visit or live in Coccidioides-endemic areas should receive primary prophylaxis for at least the first 100 days post-transplant, and duration should be extended as long as the patient remains on immunosuppression. Those with prior infection should receive secondary prophylaxis while immunosuppressed. Patients with active infection should have treatment and stabilization of infection and continue anti-fungal treatment through immunosuppression.