Steven D. Mawhorter

Histoplasmosis in solid organ transplant recipients: 10 years of experience at a large transplant center in an endemic area

BACKGROUND Many clinical scenarios have been encountered by patients who developed histoplasmosis after receiving a solid organ transplant at a large transplant center in an endemic area. METHODS Cases of posttransplantation histoplasmosis were identified by use of multiple methods, including reviews of microbiology test results, transplant databases, and billing codes. Data were obtained retrospectively. Descriptive statistics were used. RESULTS During the 1997-2007 study period, 3436 patients received a solid organ transplant, and 38 patients were identified as having posttransplantation histoplasmosis. Of these 38 patients, 9 were excluded from our study because the diagnosis was solely clinical. Of the remaining 29 patients, 14 had posttransplantation histoplasmosis (incidence, 1 case per 1000 person-years); 14 showed histologic evidence of histoplasmosis in the recipient or donor tissue, which was encountered unexpectedly at the time of transplantation; and 1 had histoplasmosis before receiving the transplant. Of the 14 patients who developed histoplasmosis after transplantation, 5 were heart transplant recipients, 3 were lung transplant recipients, 3 were kidney transplant recipients, 1 was a liver transplant recipient, 1 was a pancreas transplant recipient, and 1 was a kidney-pancreas transplant recipient. The median time from transplantation to diagnosis was 17 months (interquartile range, 8.1-46 months), and the median time from onset of symptoms to diagnosis 3 weeks (interquartile range, 1.9-6.5 weeks). All recipients had disseminated disease. The most common treatment was amphotericin B and itraconazole. All were cured, or still on treatment, but symptom-free. Of the 14 patients who had an explanted organ or donor tissue that showed histologic evidence of histoplasmosis, 13 (93%) were lung transplant recipients, and 1 (7%) was a liver transplant recipient. None of these patients developed active histoplasmosis, but all received prophylactic treatment. Finally, 1 patient had histoplasmosis before transplantation; he was treated with itraconazole 3 months before and after transplantation, and he did well. CONCLUSIONS In conclusion, posttransplantation histoplasmosis is rare (1 case per 1000 transplant-person-years; 95% confidence interval, 0.6-1.7), even in endemic areas. Prognosis is good but requires protracted therapy. Patients with latent infection did not develop posttransplantation histoplasmosis when prophylaxis was used.

The Role of Swab and Tissue Culture in the Diagnosis of Implantable Cardiac Device Infection

Background: The isolation of a pathogen is vital in the diagnosis and treatment of a device infection. A swab culture, despite poor sensitivity, is the most common method used in specimen collection.

Placebo-controlled trial of prednisone in advanced HIV-1 infection.

ObjectiveTo examine the safety and the immunologic and virologic consequences of corticosteroid use in HIV-1 infection. MethodsA randomized, double-blinded, placebo-controlled trial of corticosteroid administration in 41 patients with advanced HIV-1 infection. Patients had a baseline median CD4 cell count of 131 × 106 cells/l at enrollment and 85% had a history of opportunistic infection. All but one of the patients had been taking stable antiretroviral regimen, including a protease inhibitor in 36, for a median duration of 158 days. Patients were randomized to 8 weeks of prednisone 0.5 mg/kg daily or placebo. ResultsNo AIDS-defining events occurred; two patients in each group developed oral candidiasis, and two patients on prednisone developed mild herpes simplex flares. None who developed oral candidiasis or herpes simplex was receiving prophylaxis and each responded promptly to therapy. In the prednisone group, two patients developed hyperglycemia and one diabetic increased insulin requirements. CD4 cell counts and plasma HIV-1 RNA levels did not change, but plasma tumor necrosis factor α levels and CD38+CD8+ cells decreased significantly in those taking prednisone. ConclusionShort-term prednisone administration is well tolerated and reasonably safe in advanced HIV-1 disease and decreases immune activation without effects on HIV-1 RNA levels or CD4 cell counts. These results suggest that, in stable HIV-1 disease, these immune activation markers are more likely consequences of but not inducers of HIV-1 replication.

Donor hepatitis-C seropositivity is an independent risk factor for the development of accelerated coronary vasculopathy and predicts outcome after cardiac transplantation

BACKGROUND It is possible, but unproven, that hepatitis C (HCV) infection accelerates atherosclerosis. We evaluated the hypothesis that donor HCV seropositivity predicts mortality and the development of coronary vasculopathy in cardiac transplant recipients. METHODS Thirty-four cardiac transplant recipients who were seronegative for HCV at the time of transplantation received hearts from HCV-seropositive donors. We compared the mortality and the incidence of vasculopathy in this group of patients (study group) with a group of 183 successive heart transplant recipients (control group) with no evidence of HCV in the donor or in the recipient. RESULTS After transplantation, 75% of the HCV-seronegative patients who received hearts from HCV-seropositive donors had detectable and persistent viremia (presence of HCV-RNA by reverse-transcription polymerase chain reaction). After a mean follow-up of 4.2 +/- 1.9 years, mortality was 2.8-fold greater in the study group than in controls (95% confidence interval [CI], 1.3-5.7; p = 0.006). The risk of having any vasculopathy after a mean follow-up of 3.4 +/- 1.6 years and after adjustment for other significant risk factors was 3-fold greater (hazards ratio, 3.08; 95% CI 1.52-6.20; p = 0.001) in the HCV group compared with controls. The risk of developing advanced vasculopathy was much greater in the study group compared with controls (hazard ratio, 9.4; 97% CI, 3.3-26.6; p = < 0.0001). The risk of mortality (p = 0.005) and vasculopathy (p = < 0.0001) was greatest in patients with combined donor HCV seropositivity and the presence of antibodies against donor B cells by flow cytometry. CONCLUSION We conclude that donor hepatitis-C virus seropositivity is an independent risk factor for increased mortality and for the development of accelerated allograft vasculopathy after cardiac transplantation. These observations may have implications for the use of HCV-positive donors in heart transplant recipients.

Utility of leflunomide in the treatment of complex cytomegalovirus syndromes.

Background. Cytomegalovirus (CMV) viremia that is resistant or refractory to the standard antiviral therapy still constitutes a major threat to high-risk transplant recipients. In addition, multiple CMV recurrences may lead to neutropenia because of repeated courses of therapy with ganciclovir derivatives. Leflunomide, a drug for rheumatoid arthritis, has been reported to have anti-CMV activity. This study reports on its use in 17 transplant recipients with complex CMV syndromes who had failed or were intolerant to other therapies. Methods. Single-center, retrospective study. Clinical data were extracted from the electronic medical record. CMV DNA viral loads were performed by quantitative hybrid capture assay. Results. Leflunomide was initiated after a median of three episodes of CMV viremia, with a mean peak viral load of 245,826 copies/mL. Initial clearance of CMV viremia was observed in 14 of 17 patients (82%), and 9 of 17 (53%) patients achieved a long-term suppression of CMV recurrences. Higher peak viral load and higher viral load at the start of leflunomide therapy were associated with failure to suppress viremia. The duration of leflunomide therapy ranged from 1 to 24 months (median 3.5 months, interquartile range 2.6–7 months), and the mean time to an undetectable CMV-DNA was 1.9 months. Adverse effects included diarrhea (35%), anemia (18%), and increased liver function tests (12%). Conclusions. Leflunomide, alone or in combination, has potential utility in treatment of complex CMV syndromes and in long-term suppression of viremia. The optimal duration of therapy and the balance of risks and benefits are not yet known.

The humoral immune response to influenza vaccination in lung transplant patients

The purpose of this study was to evaluate the humoral immune response to influenza vaccination in lung transplant recipients. Antibody levels to the three viral antigens included in the 1999–2000 trivalent influenza vaccine (A/Sydney/5/97-like (H3N2), A/Beijing262/95-like (H1N1), and B/Yamanashi/16/98) were measured before and 4 weeks postvaccination in 43 lung transplant recipients and 21 healthy adult controls. The ability to develop protective antibody levels, a serological response, and the magnitude of change in levels were assessed. The humoral immune response to influenza vaccination was significantly lower in the transplant group for all three viral antigens. To A/Sydney, 95% of the control group and 40% of the transplant group developed protective levels (p=0.0009); to A/Beijing, 71% of the control group and 30% of the transplant group developed protective levels (p=0.004); and to B/Yamanashi, 48% of the control group and 19% of the transplant group developed protective levels (p=0.02). Those receiving cyclosporine had lower antibody responses when compared to those receiving tacrolimus (r=−0.3056, p=0.0463). The humoral immune response to influenza vaccination in lung transplant recipients is poor. Lung transplant recipients receiving cyclosporine may have a lower antibody response than those receiving tacrolimus. Alternative prevention strategies may be needed.

Clinical characteristics of 13 solid organ transplant recipients with ganciclovir‐resistant cytomegalovirus infection

Abstract: Background. Ganciclovir‐resistant (GCV‐R) cytomegalovirus (CMV) is now being reported with increasing frequency in solid organ transplant recipients. Objective. To describe the clinical characteristics and outcomes of all solid organ transplant patients with GCV‐R CMV seen between 1990 and 2000 at a single center. Methods. Patients with clinically suspected GCV resistance had viral isolates subjected to phenotypic analysis by plaque reduction assay, and also genotypic analysis. Medical records of the 13 patients with GCV‐R CMV were reviewed for demographic, microbiologic, clinical, and pathologic data. Results. Thirteen patients were identified, including 5 kidney, 1 heart, and 7 lung transplant recipients. All but one patient (92%) were CMV donor seropositive, recipient negative (D+/R–), and 11/13 (85%) had tissue‐invasive CMV. CMV viremia was recurrent in 9/13 (69%); in 2 others, the first CMV episode was fatal. Overall, 9/13 (69%) of patients have died, all of CMV or its complications. Of the 10 who received foscarnet, only one survived. All patients had received GCV‐based prophylactic regimens; 8/13 patients (62%) had received CMV hyperimmune globulin (CMVIG) as part of prophylaxis, 6/13 (46%) had received oral ganciclovir, and 5/13 (38%) had received intermittent (3×/week) IV ganciclovir for prophylaxis. Conclusions. GCV‐R CMV is associated with CMV D+/R– status, tissue‐invasive disease, and high mortality even with foscarnet therapy. Exposure to less than fully therapeutic levels of GCV, in the form of oral or intermittent IV GCV, is common. The use of CMVIG in prophylaxis does not appear to prevent resistance. Further work remains to be done to elucidate the risk factors and optimal mode of prophylaxis and treatment for GCV‐R CMV.

Hypogammaglobulinemia following cardiac transplantation: a link between rejection and infection

BACKGROUND Hypogammaglobulinemia (HGG) has been reported after solid organ transplantation and is noted to confer an increased risk of opportunistic infections. OBJECTIVES In this study, we sought to assess the relationship between severe HGG to infection and acute cellular rejection following heart transplantation. METHODS Between February 1997 and January 1999, we retrospectively analyzed the clinical outcome of 111 consecutive heart transplant recipients who had immunoglobulin G (IgG) level monitoring at 3 and 6 months post-transplant and when clinically indicated. RESULTS Eighty-one percent of patients were males, mean age 54 +/- 13 years, and the mean follow-up period was 13.8 +/- 5.7 months. Patients had normal IgG levels prior to transplant (mean 1137 +/- 353 mg/dl). Ten percent (11 of 111) of patients developed severe HGG (IgG < 350 mg/dl) post-transplant. The average time to the lowest IgG level was 196 +/- 125 days. Patients with severe HGG were at increased risk of opportunistic infections compared to patients with IgG > 350 mg/dl (55% [6 of 11] vs. 5% [5 of 100], odds ratio = 22.8, p < 0.001). Compared to patients with no rejection, patients who experienced three or more episodes of rejection had lower mean IgG (580 +/- 309 vs. 751 +/- 325, p = 0.05), and increased incidence of severe HGG (33% [7 of 21] vs. 2.8% [1 of 35], p = 0.001). The incidence of rejection episodes per patient at 1 year was higher in patients with severe HGG compared to patients with IgG >350 (2.82 +/- 1.66 vs. 1.36 +/- 1.45 episodes/patient, p = 0.02). The use of parenteral steroid pulse therapy was associated with an increased risk of severe HGG (odds ratio = 15.28, p < 0.001). CONCLUSIONS Severe HGG after cardiac transplantation may develop as a consequence of intensification of immunosuppressive therapy for rejection and hence, confers an increased risk of opportunistic infections. IgG level may be a useful marker for identifying patients at high risk.

Aspergillus valve endocarditis in patients without prior cardiac surgery.

Aspergillus native valve endocarditis in patients who have not had cardiac surgery is uncommon. We report 3 cases and review 58 other adult patients reported in the English-language literature. Sixty-seven percent of the patients had underlying immunosuppression. The clinical features were fever (74%), embolic episodes (69%), a new or changing heart murmur (41%), and sudden visual loss (13%). Patients with mural endocarditis were more often immunosuppressed, especially due to solid organ transplants, but had lower frequency of heart murmurs and embolic episodes. Echocardiography revealed a vegetation in 78% of all the cases in which it was performed. Examination and culture of biopsy material often helped to establish a diagnosis of Aspergillus infection. Twenty-five patients had an antemortem diagnosis. These patients received a mean cumulative amphotericin B dose of 27 mg/kg. Twenty percent (3/15) of patients who received combined surgical and medical therapy survived, compared to none of those who received medical therapy alone (p = 0.08). Patients who survived were not immunosuppressed. We conclude that native valve aspergillus infective endocarditis is uniformly fatal without surgical intervention and antifungal therapy.

Hypogammaglobulinemia and infection risk in solid organ transplant recipients.

Purpose of reviewHypogammaglobulinemia may develop as a result of a number of immune deficiency syndromes that can be devastating. This review article explores the risk of infection associated with hypogammaglobulinemia in solid organ transplantation and discusses therapeutic strategies to alleviate such a risk. Recent findingsHypogammaglobulinemia is associated with increased risk of opportunistic infections, particularly during the 6-month posttransplant period when viral infections are most prevalent. The preemptive use of immunoglobulin replacement results in a significant reduction of opportunistic infections in patients with moderate and severe hypogammaglobulinemia. SummaryMonitoring immunoglobulin G levels may aid in clinical management of solid organ transplant recipients. The preemptive use of immunoglobulin replacement may serve as a new strategy for managing solid organ transplant recipients with hypogammaglobulinemia.