Serodiagnosis of invasive aspergillosis in patients with hematologic malignancy: validation of the Aspergillus fumigatus antigen radioimmunoassay

Six hundred sixteen sera from 79 hematology patients admitted on 152 occasions were analyzed for validation of the Aspergillus fumigatus antigen radioimmunoassay (RIA). Invasive aspergillosis developed on 24 admissions of 22 patients. Maximal antigenic activity was significantly higher in patients with invasive aspergillosis than in controls (P less than .0005). At the level of antigenic activity selected as the cutoff value, the sensitivity of the RIA was 74%, the specificity 90%, the positive predictive value 82%, and the negative predictive value 85%. Antigen was detected before invasive aspergillosis was suspected during 30% of admissions and before pathological or even preliminary microbiological evidence for disease in 46%. In 17 (77%) of the 22 episodes of pulmonary aspergillosis, the RIA would have been the first positive diagnostic test for aspergillosis or would have confirmed a diagnosis established by other means. Overall, the test would have been of clinical usefulness in diagnosis, management, and prognosis in 80% of 16 fatal cases.     

Aspergillus antigen detection in bronchoalveolar lavage fluid from patients with invasive aspergillosis and aspergillomas

Improved diagnostic techniques have been needed for pulmonary aspergillosis, a common opportunistic fungal infection with a high mortality rate. Radioimmunoassay was used in this study to detect Aspergillus antigen in bronchoalveolar lavage fluid. In four patients with invasive aspergillosis or aspergillomas, Aspergillus antigen was detected in bronchoalveolar lavage fluid. In two patients, results of fungal cultures were negative or delayed. The specificity of antigen detection in bronchoalveolar lavage fluid was 91 percent in 35 control patients with a variety of pulmonary disorders. The technique of radioimmunoassay detection of microbial antigen in bronchoalveolar lavage fluid appears promising for the diagnosis of aspergillosis.     

Galactomannan antigenemia and antigenuria in aspergillosis: studies in patients and experimentally infected rabbits

Purified galactomannan (GM) from Aspergillus fumigatus was used in both a radioimmunoassay and an enzyme-linked immunoassay for antigen detection. Results of the two tests seemed interchangeable. By one or both assays, GM was detected in serum from four of 12 rabbits lethally infected with A. fumigatus in concentrations ranging from 108 to 356 ng/ml. Serum antigen was detected in only two of 12 patients with invasive aspergillosis. Results of assay for GM in urine were far more encouraging. Urinary GM was detectable throughout the course of lethal aspergillosis in all 16 rabbits, in concentrations of 24-1,900 ng/ml. Urine from seven of 13 patients with invasive aspergillosis had GM concentrations of 1-83 ng/ml. Antigen excretion roughly paralleled extent of disease.     

The role of fluconazole in the early treatment and prophylaxis of experimental invasive aspergillosis

The efficacy of fluconazole against Aspergillus fumigatus was assessed in an immunosuppressed temporarily leukopenic rabbit model of invasive aspergillosis. Therapy with fluconazole at 60 or 120 mg/kg/day was begun 24 h after lethal challenge and compared to that with amphotericin B at 1.5 mg/kg/day. Fluconazole reduced mortality compared with that in untreated controls and at 120 mg/kg/day reduced the tissue burden of A. fumigatus 10- to 100-fold in liver, kidney, and lung. However, amphotericin B was more effective in sterilizing tissues. Both fluconazole and amphotericin B dramatically decreased or eliminated circulating aspergillus antigen. Prophylaxis with fluconazole, begun 48 h before sublethal challenge, sterilized liver and kidney tissues and significantly reduced the tissue burden in lung. Early treatment with fluconazole reduced mortality and reduced antigenemia but did not sterilize tissues. Fluconazole prophylaxis at these doses prevented dissemination of invasive aspergillosis. Fluconazole was shown to have activity in the early treatment and prophylaxis of experimental invasive aspergillosis.     

Combination therapy in treatment of experimental pulmonary aspergillosis: synergistic interaction between an antifungal triazole and an echinocandin

Invasive pulmonary aspergillosis is an important cause of morbidity and mortality in immunocompromised patients. Simultaneous inhibition of fungal cell-wall and cell-membrane biosynthesis may result in synergistic interaction against Aspergillus fumigatus. We studied the antifungal activity of micafungin, a new echinocandin, in combination with ravuconazole, a second-generation triazole, against experimental invasive pulmonary aspergillosis in persistently neutropenic rabbits. This combination led to significant reductions in mortality (P相似文献   

Significance of isolation of Aspergillus from the respiratory tract in diagnosis of invasive pulmonary aspergillosis. Results from a three-year prospective study

The isolation of Aspergillus species from respiratory secretions has been regarded as being of limited usefulness in the antemortem diagnosis of invasive pulmonary aspergillosis. One hundred and eight consecutive patients were evaluated in whom Aspergillus species were isolated from respiratory secretions. Invasive aspergillosis was not demonstrated in non-immunosuppressed patients or in patients with solid tumors in the absence of neutropenia. Lung tissue was examined in 17 patients with leukemia and/or neutropenia; all had invasive aspergillosis. Tissue examination was not performed in 20 neutropenic patients; of 17 not receiving antifungal therapy, 16 died. Multivariate statistical analysis showed that neutropenia and absence of cigarette smoking were significant predictors of invasive aspergillosis in patients with respiratory tract cultures yielding Aspergillus. All cases of invasive aspergillosis were associated with A. fumigatus or A. flavus. The isolation of A. fumigatus or A. flavus from the respiratory tract of a patient with leukemia and/or neutropenia is highly predictive of invasive infection. Empiric amphotericin B therapy, without the necessity for tissue diagnosis, should be considered in this patient subgroup.     

Demonstration of antigenemia by radioimmunoassay in rabbits experimentally infected with Aspergillus.

Antigens were detected in the blood of rabbits infected with Aspergillus fumigatus by a solid-phase (tube) radioimmunoassay (RIA). The radiolabel for the assay was a polysaccharide-rich alkali extract (APAE) from the mycelia of A. fumigatus. Before this extract could be suitable labeled with 125I, it had to be conjugated with tyramine. Rabbits immunized with heat-killed mycelia had titers of antibody in serum of as high as 1:38,000 against this radiolabeled antigen. With unlabeled and unconjugated APAE as the standard antigen, the sensitivity of the RIA was 12 ng per test, or 500 ng/ml. Antigenemia was detectable by RIA three days after infection of rabbits with A. fumigatus. Blood cultures taken concomitantly were uniformly negative. These results indicate that antigenemia occurs in invasive aspergillus infection and in such cases can be detected by RIA. These observations may be important in the diagnosis of invasive aspergillus infections in humans.     

血清半乳甘露聚糖抗原及曲霉抗体检测在慢性阻塞性肺疾病合并侵袭性肺曲霉病的早期诊断价值

目的 探讨血清半乳甘露聚糖(GM)抗原及烟曲霉特异性抗体检测在慢性阻塞性肺疾病(COPD)合并侵袭性肺曲霉病(IPA)的早期诊断价值。方法 对2008年1月至2010年1月在我院行血清GM抗原及烟曲霉特异性抗体IgG、IgM检测的51例COPD患者临床资料进行回顾性分析。结果 11例患者临床拟诊IPA,治愈7例,死亡4...     

Experimental pulmonary aspergillosis due to Aspergillus terreus: pathogenesis and treatment of an emerging fungal pathogen resistant to amphotericin B

Aspergillus terreus is an uncommon but emerging fungal pathogen, which causes lethal infections that are often refractory to amphotericin B (AmB). In comparison to Aspergillus fumigatus, A. terreus was resistant to the in vitro fungicidal effects of safely achievable concentrations of AmB. These in vitro findings correlated directly with resistance of A. terreus to AmB in experimental invasive pulmonary aspergillosis. Residual fungal pulmonary burden and galactomannan antigenemia demonstrated persistent infection, despite therapy with deoxycholate AmB or liposomal AmB. By comparison, posaconazole and itraconazole resolved GM antigenemia, reduced residual fungal burden, and improved survival. There were no differences in phagocytic host response to A. terreus versus A. fumigatus; however, the rate of conidial germination of A. terreus was slower. The strain of A. terreus with the highest minimum inhibitory and minimum lethal concentration of AmB also had the lowest membrane ergosterol content. The hyphae of A. terreus in vivo displayed distinctive aleurioconidia, which may be a practical microscopic feature for rapid preliminary diagnosis.     

Serum IgE and IgG antibody activity against Aspergillus fumigatus as a diagnostic aid in allergic bronchopulmonary aspergillosis.

Serum IgE and IgG antibody activity against Aspergillus fumigatus was measured in 3 groups of subjects by 2 different immunologic methods. Group A consisted of 23 patients with allergic bronchopulmonary aspergillosis (ABPA). Group B was composed of 19 patients with extrinsic asthma who had marked immediate type skin reactivity to A. fumigatus (prick skin test, 3 or 4+) but no other manifestation of ABPA. Group C, the control group, was composed of 12 healthy subjects. Two immunological methods, including a solid-phase polystyrene tube radioimmunoassay and an iodine-125-labeled, A. fumigatus antigen radioimmunoassay, were used to study each patient's serum sample, so as to demonstrate IgE antibody activity against A. fumigatus (IgE-Af) and IgG antibody activity against A. fumigatus (IgG-Af). Both IgE-Af and IgG-Af were significantly greater among patients in Group A than among those in Group B and Group C, as measured by both methods (P is less than 0.001). The results of this study suggest that either method can be used as a diagnostic aid for ABPA. These methods may provide a laboratory test permitting diagnosis of ABPA in its early stages before bronchial or pulmonary destruction occurs.     

Serological diagnosis of pulmonary aspergillosis--measurement of IgG-, IgM- and IgA- antibodies against Aspergillus fumigatus by means of ELISA

Serological diagnosis plays an important role in the diagnosis of pulmonary aspergillosis, however, precipitation-in-gel test is neither sensitive nor quantitative. Recently, several investigators have used the ELISA technique for the detection of antibodies against Aspergillus fumigatus and reported the usefulness of this method. In this report, we measured IgG-, IgM-, and IgA- antibody titers against Aspergillus fumigatus by means of ELISA in sera from patients with several different lung diseases including pulmonary aspergillosis. The results obtained were as follows: 1) Measurement of IgG-antibody titers was most useful for the diagnosis of pulmonary aspergillosis. 2) Measurement of IgG-antibody titers was more sensitive than precipitation-in-gel test. 3) IgG-antibody titer was quantitative and reflected the clinical course of pulmonary aspergillosis.     

Characterization of antigens from Aspergillus fumigatus. IV. Evaluation of commercial and experimental preparations and fractions in the detection of antibody in aspergillosis.

Commercially available preparations of Aspergillus fumigatus, experimental extracts and fractions of A. fumigatus, and extracts of 5 other aspergilli were evaluated in a blind manner for their abilities to detect antibody in 66 serum specimens from patients with aspergilloma, allergic bronchopulmonary and invasive aspergillosis, and unconfirmed aspergillosis. Rocket immunoelectrophoresis was more sensitive than immunodiffusion in 2 dimensions. Although qualitative differences in antigen composition could be detected, commercial preparations compared favorably with the best experimental extracts in detecting positive specimens. Extracts from young, actively-growing myceliums were most effective and produced the largest numbers of precipitin bands. In contrast to all unfractionated preparations, several fractions of A. fumigatus were devoid of substances that react with C-reactive protein of serums, yet were as effective as the best preparations in detecting serums positive for Aspergillus.     

Demonstration of antigenemia in patients with invasive aspergillosis by solid phase (protein A-rich Staphylococcus aureus) radioimmunoassay.

A solid phase radioimmunoassay (RIA) was used to detect Aspergillus antigenemia in three patients, two with autopsy proved disseminated aspergillosis and one with a suspected infection. These RIA studies suggest that screening for antigenemia may be a specific and sensitive diagnostic test for disseminated aspergillosis.     

A case of non-invasive pulmonary aspergillosis that rapidly deteriorated]

The pulmonary diseases caused by the Aspergillus species include invasive forms, for example, invasive pulmonary aspergillosis, chronic necrotizing pulmonary aspergillosis, and non-invasive pulmonary aspergillosis. Though these forms are defined pathologically by the presence of the Aspergillus species that invades the lung tissue, they are used as clinical entities. We report a case of non-invasive pulmonary aspergillosis which, from the clinical data, appeared likely to be misdiagnosed as the chronic invasive form. A 45 year-old man received chemoradiotherapy for lung cancer as well as undergoing an left upper lobectomy. Two weeks after the surgery the patient developed a cough, high fever and chest pain. Chest radiography and chest computed tomography showed a rapidly enlarging cavity with an internal mass and infiltration in the left lower lung field. A transbronchial biopsy specimen of the cavity wall showed fungal hyphae. Bronchial washing culture grew Aspergillus fumigatus. Itraconazole and amphotericin B were administered, but the patient's condition did not improve. A left lower lobectomy was performed. The histologic findings showed that the fungal hyphae were only on the surface of the cavity wall, and were surrounded by necrosis and widespread inflammatory cell infiltration. No fungal invasion of the viable lung tissue was seen. The area of infiltration revealed an organizing pneumonia without Aspergillus or other organisms. Our final diagnosis was non-invasive pulmonary aspergillosis. There has been no recurrence of the lung cancer or of the pulmonary aspergillosis in the three years since surgery. It is reported that non-invasive pulmonary aspergillosis passes through a period so active that it seems to be the invasive form for its entire clinical course. To avoid confusion in diagnosis, establishment of a comprehensive clinical classification of pulmonary aspergillosis will be needed.     

Fungal respiratory disease

PURPOSE OF REVIEW: Fungal respiratory disease is associated with a high mortality in immunocompromised patients. This review aims to describe the recent advances in the aetiology, clinical presentation, diagnosis and management of fungal respiratory disease. RECENT FINDINGS: Invasive aspergillosis is an uncommon complication of hematopoietic stem cell transplants and solid-organ transplants but continues to be associated with poor outcome. Isolation of Aspergillus spp. from respiratory samples preceded acute rejection in lung-transplantation recipients. Molecular typing suggested that there was a very weak correlation between the environmental and patient isolates of Aspergillus fumigatus in invasive pulmonary aspergillosis. Serological and molecular detection of Aspergillus antigens or fungal DNA may improve the diagnosis of pulmonary aspergillosis, but the sensitivity is variable and more studies are needed. Voriconazole and caspofungin are choice to Aspergillus and Candida infection, especially to azole-resistant Candida spp. Treatment combining amphotericin B preparations, early surgical resection of infected tissue and discontinuation of immunosuppressive treatment may improve prognosis of mucormycosis. SUMMARY: Invasive filamentaous fungal infections of lung remain important causes of death in immunocompromised patients. Development of new early diagnostic tools and well-designed multicenter evaluations of diagnostic methods and therapeutic regimens available at present are the important work in the next 2-3 years.     

A solid-phase radioimmunoassay for the measurement of antibody to Aspergillus in invasive aspergillosis.

A solid-phase radioimmunoassay (SPRIA) to measure antibody responses to Aspergillus fumigatus and Aspergillus flavus antigens in invasive aspergillosis (IA) was developed and compared with immunodiffusion (ID) and counterimmunoelectrophoresis (CIE). SPRIA detected significant elevations in levels of aspergillus antibody in 15 (79)% of 19 patients with IA. Fewer patients with IA were positive by ID (give of 19) or CIE (four of 19). Only seven )8%) of 58 subjects with other fungal or bacterial infections were positive by SPRIA, as was one (5%) of 20 by ID and CIE. Weak cross-reactivity between aspergillus and candida antigens was demonstrated by SPRIA. IgG levels in patients with IA and control subjects were equivalent. Thus, an antibody response to Aspergillus can be detected in a greater percentage of patients with IA by SPRIA than by ID or CIE. Although a few patients without aspergillosis had elevated levels of aspergillus antibody, a rise in antibody level was specific for IA.     

A multicenter, open-label clinical study of micafungin (FK463) in the treatment of deep-seated mycosis in Japan

The efficacy and safety of micafungin (FK463), which is a new lipopeptide antifungal agent of the echinocandin class and is active against both Aspergillus and Candida species, were investigated in patients with deep-seated mycosis in this study. 70 patients were treated with micafungin 12.5-150 mg/d intravenously for up to 56 d. The overall clinical response rates were 60% (6/10) in invasive pulmonary aspergillosis, 67% (6/9) in chronic necrotizing pulmonary aspergillosis, 55% (12/22) in pulmonary aspergilloma, 100% (6/6) in candidemia, and 71% (5/7) in esophageal candidiasis. The response rates for patients with prior antifungal treatment which was considered ineffective or toxic, were similar to rates for patients without prior treatment. Mycological eradication was observed in patients infected with Aspergillus fumigatus, Aspergillus flavus, Aspergillus terreus, Aspergillus niger, Candida albicans, Candida glabrata, or Candida krusei. Adverse events related to micafungin were reported in 21 patients (30%), and there was no dose-related occurrence of any adverse event. It is concluded that treatment with micafungin as monotherapy seems to be effective and safe in patients with deep-seated mycosis.     

Vaccination of corticosteroid immunosuppressed mice against invasive pulmonary aspergillosis

Invasive pulmonary aspergillosis is an emerging devastating infection in the immunocompromised host that is treated with corticosteroids for neoplastic disease or for organ transplantation. By use of a model of invasive pulmonary aspergillosis in corticosteroid-treated CF-1 mice, prior infection and 2 Aspergillus fumigatus vaccine preparations (sonicate and filtrate) administered intranasally and subcutaneously were tested for efficacy in protecting against subsequent lethal A. fumigatus infection. The mortality rates were as follows: control subjects, 100%; prior infection, 12.5%; sonicate administered intranasally, 29%; sonicate given subcutaneously, 0%; filtrate given intranasally, 75%; and filtrate given subcutaneously, 50%. Prior infection and A. fumigatus sonicate vaccine administered by 2 routes protected corticosteroid-treated animals against subsequent lethal invasive pulmonary aspergillosis. The sonicate vaccine was more protective, but the subcutaneous route was more effective.     

Fever and cavitary infiltrate in a renal transplant recipient

Aspergillus infection is a rare but devastating complication following organ transplantation with high mortality rate. Aspergillus fumigatus is the most common cause of invasive aspergillosis. This fungus is present in the environment worldwide. Aspergillus infection is mainly acquired by inhalation of spores and several nosocomial infections in transplant recipient have been associated with construction work at hospitals. Risk factors for invasive aspergillosis include administration of steroid boluses, history of cytomegalovirus infection, neutropenia and prolonged antibiotic use after transplantation. Successful treatment depends on three factors: early diagnosis, aggressive antifungal therapy and decrease or removal of immunosuppression. Amphotericin deoxycholate has been the standard treatment for many years but lipid preparations for amphotericin are now used due to their significantly fewer adverse effects. A number of new antifungal drugs are now being developed including new azoles such as voriconazol and echinocandin. Invasive aspergillosis has a high mortality rate more than 95% when cerebral dissemination is demonstrated. We report the case of a 47 years old woman who received a cadaveric renal graft and developed pulmonary aspergillosis with fulminant cerebral dissemination two months later. The diagnosis of pulmonary aspergillosis was by culture isolation obtained from bronchioalveolar lavage. Removal of immunosuppresive agents and liposomal amphotericin B therapy were started shortly after admission. Brain CT scan performed on the 12th day showed cerebral dissemination. The recipient died two days later. Our patient had several risk factors such as the administration of steroid boluses and cytomegalovirus infection. Invasive aspergillosis must be always included in the differential diagnosis of fever and pulmonary disease in the renal transplant recipient.     

Invasive pulmonary aspergillosis

Invasive pulmonary aspergillosis is the most common fungal pulmonary infection in certain immunocompromised patients. The most commonly affected patients are hematopoietic stem cell transplant recipients and patients with hematological malignancies undergoing intensive chemotherapy. The survival of patients with invasive pulmonary aspergillosis is very poor because of difficulties in early diagnosis and lack of effective treatment options. Research efforts are being made constantly to improve different diagnostic techniques. Early, repeated, high resolution computed tomography of the chest, and sequential nonculture-based monitoring of Aspergillus antigen and DNA can improve earlier diagnosis. New antifungal drugs for treatment and prevention of invasive pulmonary aspergillosis continue to emerge, with better safety, efficacy, and pharmacologic profiles.