Aspergillus infection of prosthetic aortic valves

Aspergillus endocarditis: a review of the literature

We present a case of cardiac device-related Aspergillus endocarditis in a patient with a pacemaker and an allogeneic bone marrow transplant to segue into a review of the Aspergillus endocarditis literature. Aspergillus endocarditis should be suspected in patients with underlying immunosuppression, negative cultures, and a vegetation on echocardiography. Diagnosis ultimately requires confirmation by tissue histology and culture. The optimal treatment approach often requires aggressive surgical debridement in conjunction with prolonged antifungal therapy.

Clustering of invasiveAspergillus ustuseye infections in a tertiary care hospital: A molecular epidemiologic study of an uncommon species

Aspergillus infections are being increasingly recognized as an important cause of morbidity and blindness. We report here the first cluster of Aspergillus ustus endophthalmitis cases which occurred in a large tertiary care hospital during the period October 2003 to June 2004. In three of the cases, the patients required enucleation following cataract surgery, while the fourth involved a fatal infection in a pediatric patient hospitalized for osteopetrosis. Patient charts from the four cases were reviewed retrospectively and indicated that postoperative signs of fungal endophthalmitis developed in the patients 1-11 weeks after surgery. The molecular characterization of the isolates and their epidemiological relatedness were evaluated by Random Amplification of Polymorphic DNA (RAPD). A source investigation of this mini outbreak was performed by environmental sampling, but no isolates of A. ustus were recovered from these studies. All A. ustus strains isolated from three patients with fungal endophthalmitis had the same RAPD pattern suggesting a common source. The strain from the pediatric patient differed from the ophthalmic isolates in five electrophoretic loci. The latter was included solely as an outbreak, unrelated control to evaluate the discriminatory power of the molecular typing method employed in the analysis of the ophthalmic strains. These cases illustrate the potential for uncommon species like A. ustus to cause high morbidity and mortality in some clinical settings. Aspergillus ustus endophthalmitis is a serious and devastating complication of ocular surgery. It is unknown whether ongoing hospital construction may have contributed to this cluster of cases. Random amplification of polymorphic DNA may give valuable clues about the clonality of A. ustus strains.

Post-operative aspergillosis

While invasive aspergillosis occurs typically in severely immunocompromised patients, cases of surgical site infection have been reported in immunocompetent individuals. The Medline, LILACS and EMBASE databases were searched for descriptions of cases of post-operative aspergillosis, and references from relevant articles and conference abstracts were reviewed. More than 500 cases of post-operative aspergillosis were found. Cardiac surgery (n = 188), ophthalmological surgery (n > 90) and dental surgery (n > 100) were associated with the majority of cases. Other cases involved wound infections (n = 22), bronchial infections (n = 30), mediastinitis (n = 11), pleural aspergillosis (n = 1), infections following orthopaedic surgery (n = 42), vascular prosthetic surgery (n = 22), breast surgery (n = 5), abdominal surgery (n = 10) and neurosurgery (n = 25). In most patients, the source was presumed to be airborne infection during the surgical procedure. Prevention of these infections requires special care of the ventilation system in the operating room. Successful treatment requires rapid diagnosis, surgical debridement and antifungal therapy, often with voriconazole. In order to improve the outcome, better diagnostic methods are needed, particularly for cases of endocarditis and aortitis.

Aspergillus ustus infections among transplant recipients

This is the first report of clustered Aspergillus ustus causing systemic disease in transplant patients.

Aspergillus ustus is a mold that rarely infects humans; only 15 systemic cases have been reported. We report the first outbreak of invasive infection caused by A. ustus among hematopoietic stem cell transplant (HSCT) recipients. Six patients with infections were identified; 3 infections each occurred in both 2001 and 2003. Molecular typing by using randomly amplified polymorphic DNA (RAPD) and antifungal drug susceptibility testing were performed on clinical and environmental isolates recovered from our hospital from 1999 to 2003. The highest overall attack rate in HSCT patients was 1.6%. The overall death rate was 50%, and death occurred within 8 days after diagnostic culture collection. Clinical isolates exhibited decreased susceptibility to antifungal drugs, especially azoles. RAPD and phylogenetic analysis showed genetic similarity between isolates from different patients. Based on the clustering of cases in space and time and molecular data, common-source acquisition of this unusual drug-resistant species is possible.

The invasive and saprophytic syndromes due to Aspergillus spp

Aspergillus spp. produce a wide range of invasive and sapropytic syndromes which may involve any tissue. Within a given tissue or organ the pathology and pathogenesis varies enormously, ranging from angioinvasive disease to noninvasive saprophytic disease. The individual invasive and saprophytic syndromes in which a causative role can be attributed to Aspergillus spp. are detailed specifically with reference to the underlying pathology and pathogenesis, the clinical setting and features, and the manner in which a diagnosis can be established.

Disseminated aspergillosis caused by Aspergillus ustus in a patient following allogeneic peripheral stem cell transplantation

The first case of disseminated aspergillosis caused by Aspergillus ustus in an allogeneic peripheral stem cell transplant patient is described. The patient, a 46-year-old female with a history of myelodysplastic syndrome, underwent high-dose chemotherapy and total body irradiation prior to transplantation. She was released from the hospital 49 days posttransplant (p.t.) in a stable condition with an absolute neutrophil count (ANC) of 2,700 cells per microl. Multiple antimicrobial agents, including itraconazole (ITR), were prescribed during hospitalization and at the time of discharge. Three days after discharge, the patient was readmitted with hemorrhagic cystitis, persistent thrombocytopenia, and bilateral pulmonary consolidation, although no fever was present. The ANC at the time of readmission was 3,500. Upon detection of a pulmonary nodule (day 67 p.t.), a bronchoalveolar lavage was performed; the lavage fluid was positive for both cytomegalovirus and parainfluenza virus and negative for fungus. The patient was placed on ganciclovir. A biopsy specimen from a leg lesion also noted on day 67 p.t. revealed septate hyphae consistent with Aspergillus species, and a culture subsequently yielded Aspergillus ustus. Confirmation detection of A. ustus was made by demonstration of characteristic reproductive structures with the presence of Hülle cells. On day 67 p.t., ITR was discontinued and liposomal amphotericin B (AMB) was initiated. The patient's condition worsened, and she died 79 days p.t. At the time of autopsy, septate hyphae were present in heart, thyroid, and lung tissues, with lung tissue culture positive for A. ustus. In vitro susceptibility testing indicated probable resistance to AMB but not to ITR. This case supports the need for the development of rapid methods to determine antifungal susceptibility.

False aneurysm infected by Aspergillus fumigatus: an unusual complication of aortofemoral bypass graft

Two cases of Aspergillus fumigatus infection of aortobifemoral prosthetic grafts are reported. Both patients were treated successfully by excision of the infected prosthetic material, axillofemoral extra-anatomic bypass, and prolonged medical treatment. The patients received amphotericin B, 5-flucytosine and itraconazole until negative aspergillus serology was obtained (at 9 and 18 months, respectively). Later, repeat disobliteration procedures for thrombosis of the axillofemoral bypass were required. No recurrent aspergillus infection was found.

Aspergillus mural endocarditis. Clinical and echocardiographic diagnosis

Fungal mural endocarditis is a rare entity in which the antemortem diagnosis is seldom made. This case presentation describes a patient in whom the clinical diagnosis of Aspergillus mural endocarditis was made by echocardiography and by biopsy of a peripheral embolic lesion. This led to a combined medical and surgical approach to therapy.

Successful treatment of post-mitral valve annuloplasty Aspergillus flavus endocarditis

Aspergillus endocarditis is associated with a very high mortality. Of approximately 67 cases reported in the English language literature, there have been only two known survivors. This report describes a patient with Aspergillus flavus endocarditis after mitral valve annuloplasty who recovered with combined surgical and antifungal therapy. This is the first successfully treated case due to A. flavus and the first involving an annuloplasty ring.

Cardiac fungal infections: review of autopsy findings in 60 patients

An autopsy study of 60 patients with fungal infections of the heart was undertaken. The patients ranged in age from 2 months to 79 years. Fifteen of the patients had undergone cardiac surgery; neoplasms were found in 13, renal failure in eight, bacterial infections in five, liver disease in five, gastrointestinal disorders in five, and immune disease in four; two had been intravenous drug abusers; other miscellaneous disorders were observed in three. The fungal infection was limited to the myocardium in 27 patients and to the endocardium in 17 patients. Myocardium and endocardium were involved in nine patients and pericardium and myocardium in five; two patients had pericarditis alone. The most frequent organism was Candida (62 per cent). Aspergillus (12 per cent) and Phycomycetes (12 per cent) were also found frequently. In 51 patients (85 per cent) other deep organs, usually lung, kidney, brain, or spleen were involved. Cultures for fungus had been positive in 26 patients prior to death, and postmortem cultures were positive in 29 patients. Patients who had undergone cardiac surgery had a higher incidence of endocarditis (93 per cent), with Candida (53 per cent) being the most frequent cause. Patients who had received antineoplastic drugs, antibiotics, or corticosteroids had a higher incidence of myocarditis (79 per cent), again most often due to Candida (60 per cent).

Aspergillus niger endocarditis complicating aortic tissue valve replacement

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Prosthetic valve endocarditis: clinicopathologic analysis of 22 necropsy patients with comparison observations in 74 necropsy patients with active infective endocarditis involving natural left-sided cardiac valves

Clinical and morphologic features are described in 22 necropsy patients with endocarditis involving rigid-framed prosthetic valves: aortic in 15 patients and mitral in 7. The interval from valve replacement to onset of symptoms of prosthetic valve endocarditis was less than 2 months in 8 patients and longer than 2 months in 14 patients. The most frequent infecting organism was the Staphylococcus (13 patients). In each of the 22 patients the infection was located behind the site of attachment of the prosthesis to the valve ring, and the infection spread to adjacent structures in 13 patients, 11 of whom had aortic prostheses. Prosthetic detachment causing severe regurgitation occurred in 12 of the 15 patients with an infected aortic valve prosthesis, and in 2 of the 7 with an infected mitral valve prosthesis. Prosthetic obstruction by vegetative material occurred in 5 of 7 patients with prosthetic mitral infection and in only 1 of 15 with prosthetic aortic infection. High degrees of conduction defects developed in seven patients with aortic prosthetic valve endocarditis: complete heart block in five, and complete left bundle branch block in two. Comparison of observations in the 22 patients with prosthetic valve endocarditis with those in 74 patients with active infective endocarditis involving natural left-sided cardiac valves revealed significant (P less than 0.05) differences in the percent with ring abscess, hemodynamic consequences of the endocarditis (valve stenosis), frequency of Staphylococcus as the causative organism and percent with complete heart block or left bundle branch block. No significant differences were observed between the two groups when comparing age, sex, type of underlying valve disease or frequency of organ infarcts of splenomegaly.

Opportunistic endocarditis following open-heart surgery

The incidence of endocarditis following open-heart operations is declining, but the relative incidence of endocarditis by the opportunistic organisms, both bacterial and fungal, has increased. These "opportunists" require careful identification and sensitivity testing so that appropriate therapy can be planned. In cases of candida endocarditis, a positive precipitin test and elevated candida antibody titer may provide an earlier means of diagnosis than blood cultures. These patients should be treated promptly with adequate dosages of specific antimicrobial or antifungal agents. Reoperation should be considered early if there is evidence of valve dehiscence or embolic phenomena or if drug therapy fails to control the infection.