The clinical spectrum of aspergillosis--part 1: epidemiology, pathogenicity, infection in animals and immunology of Aspergillus

Invasive maxillary aspergillosis in a patient with systemic lupus erythematosus: Case report

Introduction

Invasive aspergillosis (IA) is a fungal infection caused by Aspergillus species (spp.). Aspergillosis is the most common source of opportunistic fungal infection in humans. IA can cause serious complications related to high morbidity and mortality in immunocompromised patients.

Presentation of case

We report a case of a 22-year-old female with a chief complaint of having a hole in the roof of her mouth. She was diagnosed with SLE in 2009. She had been consuming oral methylprednisolone ever since. In 2018, she experienced worsened symptoms and was hospitalized. She experienced swelling and bleeding of her gums and some of her teeth becoming loose and falling out, and then developing a hole in the roof of her mouth. Subsequently, she was treated with oral cyclophosphamide, oral mycophenolate sodium, and oral fluconazole. She was asked to stop taking oral methylprednisolone. In 2019, the palate biopsy was performed and showed Aspergillus spp. invading the palate. Afterward, the patient was referred to our clinic for defect closure. The patient was operated on for debridement and reconstruction of the defect. There was no recurrence of the defect or complications observed in the follow-up. The patient was satisfied with the surgical results.

Discussion

IA is a destructive and potentially harmful opportunistic fungal infection and treatments with surgical interventions should be well-thought-out in immunocompromised patients.

Conclusion

The management of IA are controlling any underlying diseases and surgical debridement or necrotomy. Generally, antifungal therapy and prompt surgical intervention are successful in managing invasive aspergillosis.

A questionnaire-based study on the role of environmental factors in allergic bronchopulmonary aspergillosis

Background and Aims:

Allergic bronchopulmonary aspergillosis (ABPA) is an immunological disorder caused by hypersensitivity against Aspergillus fumigatus. The pathogenesis of ABPA remains unknown. Few studies have investigated the role of environmental factors in pathogenesis of ABPA. Herein, we investigate the role of environmental factors in ABPA.

Materials and Methods:

In this prospective case-control study, consecutive patients with asthma (Aspergillus sensitized and unsensitized) and ABPA were investigated using a standardized questionnaire to enquire into their demographic characteristics, clinical details, exposure to organic matter and living conditions (home environment, presence of moisture in the walls, and others). Asthma severity and control was assessed using the 2002 The Global Initiative for Asthma (GINA) recommendations and asthma control test, respectively.

Results:

During the study period, 202 subjects of asthma (103 and 99 Aspergillus unsensitized and sensitized asthma, respectively) and 101 ABPA with a mean (SD) age of 35.3 (14.7) years were included. The baseline characteristics were similar in the two groups except for a higher prevalence of severe persistent asthma in the ABPA group (79% vs. 44%, P = 0.0001). No significant differences in environmental factors were noted in the ABPA population compared to asthmatic patients except for a higher rural residence in ABPA (47% vs. 66%, P = 0.007).

Conclusions:

The study found no significant environmental differences in ABPA compared to asthmatic patients. It is likely that environmental factors are not the primary pathogenetic factors in causation of ABPA.

Aspergillus-associated airway disease, inflammation, and the innate immune response

Aspergillus moulds exist ubiquitously as spores that are inhaled in large numbers daily. Whilst most are removed by anatomical barriers, disease may occur in certain circumstances. Depending on the underlying state of the human immune system, clinical consequences can ensue ranging from an excessive immune response during allergic bronchopulmonary aspergillosis to the formation of an aspergilloma in the immunocompetent state. The severest infections occur in those who are immunocompromised where invasive pulmonary aspergillosis results in high mortality rates. The diagnosis of Aspergillus-associated pulmonary disease is based on clinical, radiological, and immunological testing. An understanding of the innate and inflammatory consequences of exposure to Aspergillus species is critical in accounting for disease manifestations and preventing sequelae. The major components of the innate immune system involved in recognition and removal of the fungus include phagocytosis, antimicrobial peptide production, and recognition by pattern recognition receptors. The cytokine response is also critical facilitating cell-to-cell communication and promoting the initiation, maintenance, and resolution of the host response. In the following review, we discuss the above areas with a focus on the innate and inflammatory response to airway Aspergillus exposure and how these responses may be modulated for therapeutic benefit.

Allergic bronchopulmonary aspergillosis

Allergic bronchopulmonary aspergillosis (ABPA) is an immunologic pulmonary disorder caused by hypersensitivity to Aspergillus fumigatus. Clinically, a patient presents with chronic asthma, recurrent pulmonary infiltrates, and bronchiectasis. The population prevalence of ABPA is not clearly known, but the prevalence in asthma clinics is reported to be around 13%. The disorder needs to be detected before bronchiectasis has developed because the occurrence of bronchiectasis is associated with poorer outcomes. Because many patients with ABPA may be minimally symptomatic or asymptomatic, a high index of suspicion for ABPA should be maintained while managing any patient with bronchial asthma whatever the severity or the level of control. This underscores the need for routine screening of all patients with asthma with an Aspergillus skin test. Finally, there is a need to update and revise the criteria for the diagnosis of ABPA. This review summarizes the advances in the diagnosis and management of ABPA using a systematic search methodology.

Allergic bronchopulmonary aspergillosis in paediatric cystic fibrosis patients

Allergic bronchopulmonary aspergillosis (ABPA) is a severe complication in children, adolescents and adults with cystic fibrosis (CF), the prevalence of which ranges from 6-25%. The disease is the result of the colonisation of the respiratory tract by fungi of the genus Aspergillus, commonly Aspergillus fumigatus, and subsequent host sensitisation to fungal antigens, accompanied by a Th2 CD4 type response mediated by the production of specific IgE. The consequent inflammatory and obstructive bronchopulmonary injury can progress to fibrosis. The diagnosis should be considered early in patients with CF who show wheezing, transient pulmonary infiltrates and reduced lung function. The objective diagnosis is not straightforward because of overlapping clinical and radiological signs, particularly the progression of bronchiectasis. Specific criteria are needed for the diagnosis of ABPA in patients with CF, such as those proposed by the Cystic Fibrosis Foundation. The study of specific IgE against recombinant antigens of A. fumigatus has contributed to the early diagnosis of ABPA with high sensitivity and specificity. The technique has also shown promise in the follow-up of patients after steroid therapy and the early detection of recurrences. Treatment consists of long-term systemic corticosteroid usage, the monitoring of their adverse effects, and of the measurement of total serum IgE levels. The concomitant use of oral itraconazole seems to promote a better control of the disease and to reduce the duration of systemic steroid therapy but its use continues to be controversial. Controlled studies involving larger numbers of patients are necessary if we are to better understand the management of ABPA.

Prenatal cigarette smoke decreases lung cAMP and increases airway hyperresponsiveness

Epidemiologic studies suggest that in utero exposure to tobacco smoke, primarily through maternal smoking, increases the risk for asthma in children; however, the mechanism of this phenomenon is not clear. Cyclic adenosine monophosphate relaxes airway smooth muscles in the lung and acts as an antiasthmatic. In this study, we examined the effects of in utero cigarette smoke exposure of Balb/c mice on airway responsiveness, as determined by Penh measurements. Animals exposed prenatally but not postnatally to cigarette smoke exhibited increased airway hyperresponsiveness after a single intratracheal injection of Aspergillus fumigatus extract. The increased airway hyperresponsiveness was not associated with increased leukocyte migration or mucous production in the lung but was causally related to decreased lung cyclic adenosine monophosphate levels, increased phosphodiesterase-4 enzymatic activity, and phosphodiesterase-4D (PDE4D) isoform-specific messenger ribonucleic acid expression in the lung. Exposure of adult mice to cigarette smoke did not significantly alter airway responsiveness, cyclic adenosine monophosphate levels, or the phosphodiesterase activity. These results suggest that prenatal exposure to cigarette smoke affects lung airway reactivity by modulating the lung cyclic adenosine monophosphate levels through changes in phosphodiesterase-4D activity, and these effects are independent of significant mucous production or leukocyte recruitment into the lung.

Indoor air quality and health does fungal contamination play a significant role?

Fungal contamination in buildings can vary greatly, and their presence in a dwelling does not necessarily constitute exposure. Measurement of mold spores and fragments varies depending on the methodology and instruments used. Meaningful comparison of data is rarely possible. The presence of a specific immune response to a fungal antigen only connotes that exposure to one or more related species has occurred, but not that there is a symptomatic clinical state. The response of individuals to indoor bioaerosols is complex and depends on age, gender, state of health, genetic makeup, and degree and time of bioaerosol exposure. In general, mold contamination in buildings is associated with incursion of water or moisture, which should be remedied as efficiently as possible. When disease occurs, it more likely is related to transient annoyance or irritational reactions. Allergic symptoms may be related to mold proliferation in the home environment. Because molds are encountered both indoors and outdoors, it is difficult to determine where the sensitivity initially arose and if the response is solely provoked by either an indoor or outdoor source. As an indoor allergen, mold is considered to be an infrequent participant in the induction of allergic disease when compared with housedust mites, animal dander, and cockroach allergens. Infection in healthy individuals is rare and usually is caused by an outdoor source. Building-related disease caused by mycotoxicosis has not been proved in the medical literature.

Putative virulence factors of Aspergillus fumigatus

Various putative virulence factors of Aspergillus fumigatus have been studied over the past decades. A. fumigatus gliotoxin is a potent inhibitor of the mucociliary system. Several fungal metabolites interfere with phagocytosis and opsonization including toxins, 'conidial inhibitory factor', 'A. fumigatus diffusible product' and 'complement inhibitory factor'. A. fumigatus can bind specifically to different host tissues components, whereas toxins give a general and significant immunosuppressive effect on host defences. Circumstantial evidence links the production of elastinolytic proteases with the ability to cause disease. However, none of the reports demonstrates conclusively a decisive role for any of the virulence factors described thus far. It is conceivable that proteolytic enzyme activities such as those expressed by AFAlp are one of a number of factors, each with a minor effect, that combine to facilitate disease progression.

Mitochondrial cytochrome b gene analysis of Aspergillus fumigatus and related species

Nucleotide sequences of 426 bp from the mitochondrial (mt) cytochrome b genes of six anamorph species and two species of Neosartorya teleomophs of Aspergillus section Fumigati were determined. These sequences were used to build nucleotide- and amino acid-based trees for phylogenetic analysis. Thirteen strains of A. fumigatus including 10 clinical isolates of A. fumigatus, 1 type culture of A. fumigatus var. fumigatus, 1 type culture of A. fumigatus var. ellipticus, and 1 strain of A. fumigatus var. albus, had the same nucleotide sequences. One strain of A. fumisynnematus, two strains labeled A. neoellipticus, two strains of A. viridinutans, and one strain of A. duricaulis had distinct nucleotide and amino acid sequences. Two strains of A. brevipes were divided into two types. One produced a 1,500-bp fragment that included an intron. The nucleotide sequences of its two exons were similar to those of the A. fumigatus, and the derived amino acid sequence was the same as that for A. fumigatus. The other produced a 426-bp fragment and had the same nucleotide and amino acid sequences as A. unilateralis. Neosartorya fischeri var. fischeri and N. stramenia had nucleotide sequences that differed from that of A. fumigatus. These species possessed their own characteristic nucleotide sequences that differed from each other. In comparisons of homologous sequences from four other pathogenic species of Aspergillus, regions specific to section Fumigati were found. The mt cytochrome b gene analysis was valuable for the identification, classification, and phylogenetic analysis of isolates of section Fumigati.

Experimental zygomycosis in rabbits: clinicopathological studies

Zygomycosis was produced experimentally in 20 New Zealand white rabbits (Oryctolagus cuniculus) by intra-nasal administration of spores of Absidia corymbifera. Infected animals showed dullness, depression, coughing and mucopurulent nasal discharge, but no mortality. Haematology revealed no significant change in Hb and PCV, but leukocytosis due to neutrophilia in the initial stages of the experiment. There was a significant increase in serum total proteins, creatinine, AST, ALT, total Igs and CICs. A. corymbifera specific IgM and IgG antibodies were detected in the sera of the infected animals. Gross lesions consisted of pneumonic consolidations of the anteroventral lobes of the lungs. Microscopically, histology showed formation of pyogranulommas in the lungs. Fungal elements typical of A. corymbifera were demonstrated in the tissues upto 15 days after infection by special stains and confirmed by indirect immunoperoxidase. Re-isolation of the fungus from lungs was also achieved consistently upto 15 days only. It was concluded that intra-nasal instillation of A. corymbifera in rabbits produced significant clinico-pathological alterations with the lesions confined mainly to the lungs. In the present study, neither systemic dissemination of the disease occurred nor were kidneys site of predilection as reported earlier.

Conformational and linear B-cell epitopes of Asp f 2, a major allergen of Aspergillus fumigatus, bind differently to immunoglobulin E antibody in the sera of allergic bronchopulmonary aspergillosis patients

Asp f 2 is a major Aspergillus fumigatus allergen involved in allergic bronchopulmonary aspergillosis. Knowledge of the B-cell epitopes may contribute to the understanding of immunoregulation and immunodiagnosis. To elucidate the immunoglobulin E (IgE) binding epitopes in the linear sequence of Asp f 2, we synthesized decamer peptides spanning the whole molecule of Asp f 2 on derivatized cellulose membranes and evaluated IgE binding in ABPA patient and control sera. Peptides three to five amino acids long were synthesized based on amino acid sequences within the IgE binding regions and evaluated for the specificity of epitope antibody interactions. Nine IgE binding regions were recognized in this protein of 268 amino acid residues. Of the nine epitopes, seven (ATQRRQI, RKYFG, HWR, YTTRR, DHFAD, ALEAYA, and THEGGQ) are present in the hydrophilic regions of Asp f 2. Immunologic evaluation of the three recombinant fragments, Asp f 2A encompassing the N-terminal epitope region, Asp f 2B without N- and C-terminal regions of the protein, and Asp f 2C representing C-terminal epitopes, revealed that either the N- or C-terminal region of the protein is essential for the correct folding and conformation for IgE antibody binding.

Immunological characterization of Asp f 2, a major allergen from Aspergillus fumigatus associated with allergic bronchopulmonary aspergillosis

The 37-kDa recombinant protein Asp f 2, encoding an allergen of Aspergillus fumigatus, was expressed in a prokaryotic expression system and immunologically evaluated for its functional and structural properties. The open reading frame for a 310-amino-acid-long protein was shown to encode a signal peptide of 31 amino acids. A native 37-kDa culture filtrate protein and a 55-kDa mycelial glycoprotein (gp55) exhibited complete N-terminal sequence homology to Asp f 2. A GenBank search for homologous proteins revealed 60 and 44% sequence homologies to the cytosolic protein ASPND1 from Aspergillus nidulans and fibrinogen binding protein from Candida albicans, respectively. The glycosylation sites and cysteine molecules are conserved in all the three proteins. The extracellular matrix protein laminin showed a dose-dependent interaction with Asp f 2. This protein, expressed as a major cell-associated protein within 24 h of in vitro fungal culture, comprises 20 to 40% of total fungal protein. Furthermore, both native and recombinant Asp f 2 exhibited specific immunoglobulin (IgE) binding with allergic bronchopulmonary aspergillosis (ABPA) and cystic fibrosis-ABPA patients, whereas A. fumigatus-sensitized allergic asthma and normal control subjects failed to show IgE binding with Asp f 2. These results indicate that Asp f 2 is a major allergen of A. fumigatus exhibiting IgE antibody binding with sera from patients with ABPA. The antigen should be explored further for its potential role in the differential diagnosis of A. fumigatus-associated allergic diseases.

Humoral and cell-mediated autoimmunity in allergy to Aspergillus fumigatus

A cDNA encoding an allergenic protein was isolated from an Aspergillus fumigatus (A. fumigatus) cDNA library displayed on the surface of filamentous phage. Serum immunoglobulin E (IgE) from A. fumigatus-sensitized individuals was used to enrich phage-expressing gene products binding to IgE. One of the cDNAs encoded a 26.7-kD protein that was identified as a manganese superoxide dismutase (MnSOD) sharing 51.5% identity and 67.2% homology to the corresponding human enzyme. Both human and A. fumigatus MnSOD coding sequences were expressed in Escherichia coli as [His]6-tagged fusion proteins and purified by Ni(2+)-chelate affinity chromatography. The two recombinant MnSODs were both recognized by IgE antibodies from subjects allergic to the A. fumigatus MnSOD and elicited specific immediate type allergic skin reactions in these individuals. Moreover, both human and A. fumigatus MnSOD induced proliferation in peripheral blood mononuclear cells of A. fumigatus-allergic subjects who showed specific IgE responses and reacted in skin tests to MnSOD. These observations provide evidence for autoreactivity to the human MnSOD in allergic persons sensitized to an environmental allergen from A. fumigatus who share a high degree of sequence homology to the corresponding human enzyme.

Molecular cloning and expression of a recombinant Aspergillus fumigatus protein Asp f II with significant immunoglobulin E reactivity in allergic bronchopulmonary aspergillosis

The cDNA of Aspergillus fumigatus encoding an allergen was cloned and expressed in Escherichia coli. The 987 bp long cDNA clone expressed a recombinant protein Asp f II of 34 kd. This protein exhibited binding to immunoglobulin E (IgE) in the serum samples from patients with allergic bronchopulmonary aspergillosis (ABPA). The patients with ABPA and central bronchiectasis demonstrated high levels of serum IgE antibodies, whereas patients with ABPA without central bronchiectasis, patients with asthma and Aspergillus skin test reactivity but no evidence of ABPA, and patients with aspergilloma showed only low levels of IgE antibody to Asp f II. In two-dimensional electrophoresis, a native antigen electroeluted from an A. fumigatus culture filtrate antigen preparation showed an isoelectric point and molecular weight similar to that of Asp f II. In a competitive enzyme-linked immunosorbent assay (ELISA), the IgE antibody reactivity of Asp f II with patient serum samples could be significantly inhibited by culture filtrate antigens of A. fumigatus. These results indicate that Asp f II has immunologic reactivities comparable to those of native A. fumigatus antigens. The recombinant Asp f II can be expressed in E. coli in large quantities and should prove useful as a standardized allergen for sensitive and specific immunodiagnosis of ABPA, especially in patients with central bronchiectasis.

DNA typing of epidemiologically-related isolates of Aspergillus fumigatus

Invasive aspergillosis is often nosocomially acquired and carries a high mortality. Molecular typing methods to discriminate isolates have now been developed. Using simple restriction endonuclease (Sal1 and Xho1) digestion of total genomic DNA, we have typed 25 epidemiologically-related isolates of A. fumigatus from six hospital episodes of invasive aspergillosis. Eight DNA types were found and in each case the DNA type matched precisely the epidemiological data. Thus DNA typing of A. fumigatus can provide the means to match isolates from linked sources and distinguish isolates from diverse origins.

Hypersensitivity pneumonitis resulting from Aspergillus fumigatus in a greenhouse

A 57-y-old female who had cultivated vegetables in a plastic greenhouse developed a case of hypersensitivity pneumonitis from Aspergillus fumigatus. This report exemplifies a potential hazard caused by a thermotolerant fungus, A. fumigatus, in a poorly constructed greenhouse.

Recombinant Aspergillus fumigatus allergen I/a (rAsp f I/a) in the diagnosis of Aspergillus related diseases

A. fumigatus allergen I/a (rAsp f I/a) was produced in Escherichia coli, affinity purified by Ni(2+)-chelate chromatography and refolded. rAsp f I/a binds IgE of A. fumigatus-allergic individuals as shown by ELISA, dot blots and Western blots. In addition, rAsp I/a elicited positive immediate type I skin reactions in individuals allergic to A. fumigatus but not in control individuals. Hence, rAsp f I/a can be used as a standardized antigen/allergen for an improved serological and clinical diagnosis of A. fumigatus-associated diseases.

Characterization of a monoclonal antibody against concanavalin A binding antigen of Aspergillus fumigatus

A monoclonal antibody was produced against a Concanavalin A (Con A) binding major epitope of Aspergillus fumigatus using a novel method of immunization. The antigen was purified using monoclonal antibody affinity chromatography reacted with specific antibodies present in human sera. Both allergic bronchopulmonary aspergillosis and aspergilloma showed high levels of antibody, against this purified antigen, when compared to normal controls. Similar results were obtained when the monoclonal antibody was used in a capture antigen assay. The antibody reacted with several A. fumigatus extracts in rocket electrophoresis demonstrating a single precipitin arc, which disappeared when Con A intermediate gel was used. This monoclonal antibody demonstrated reactivity only with cytoplasmic components of hyphae and spores of A. fumigatus, when a colloidal gold was used as a probe in immunoelectron microscopy.

Detection of IgG and IgE antibodies to Aspergillus fumigatus in human sera by immunogold assay

An immunogold assay (IGA) was developed to detect IgG and IgE antibodies to Aspergillus fumigatus. Sixteen sera from patients with allergic bronchopulmonary aspergillosis (ABPA), aspergilloma, and normal controls were studied. All sera were also evaluated for antibodies against A. fumigatus by biotin-avidin linked enzyme immunosorbent assay (BALISA) and by agar gel double diffusion method. A. fumigatus specific IgG and IgE antibodies could be detected by IGA in all the patients' sera but not in the sera of normal controls. Both IgG and IgE antibodies to A. fumigatus could be demonstrated in all the sera by BALISA and normal controls showed only low levels of these antibodies. There was a positive correlation between the degree of reactivity detected by IGA, the BALISA titer and the precipitins by agar gel diffusion. It can be concluded that IGA is a reliable, sensitive and simple method capable of detecting both IgG and IgE antibodies against A. fumigatus in patient serum.

Identification of extracellular siderophores of pathogenic strains of Aspergillus fumigatus

Clinical and environmental isolates of Aspergillus fumigatus synthesized extracellular siderophores when grown in defined medium. Six hydroxamate siderophores were purified from culture filtrates and identified by thin layer chromatography. The most prominent siderophore was identified as N,N',N"-triacetylfusarinine C and the second most prominent siderophore was identified as ferricrocin. In addition, a hydrolytic product of N,N',N"-triacetylfusarinine C was identified. Three other siderophores were present in smaller amounts and were not identified. Since the same siderophores were produced by isolates from diseases of varying severity and from environmental material, it is unlikely that the extracellular siderophores function as virulence factors during infection. However, they may function as growth factors by mediating iron uptake by the fungus in the micro-environment of the inflammatory focus.

Allergic bronchopulmonary aspergillosis from a contaminated dump site

The inhalation of Aspergillus fumigatus (Af) spores liberated from a municipal leaf compost site led to the development of allergic bronchopulmonary aspergillosis (ABPA) in a patient living in the area. The patient developed characteristic symptoms of ABPA and demonstrated precipitins against Af antigens in his sera. The potential hazard caused by uncontrolled composting resulting in the dissemination of several allergenic fungi and other microbes is exemplified by this case.

Invasive aspergillosis in an alpaca (Lama pacos)

An invasive form of aspergillosis in an alpaca (Lama pacos) is described, with dissemination causing small abscesses and multifocal areas of necrosis in the lung, heart, spleen and kidneys. Histological sections showed hyphae morphologically compatible with an Aspergillus species. Direct immunofluorescent testing confirmed the diagnosis of aspergillosis.

Dot-immunobinding assay in the detection of IgG antibodies against farmer's lung antigens

Circulating antibodies against Faenia rectivirgula, Thermoactinomyces candidus, T. vulgaris and Aspergillus fumigatus were studied in the sera of 14 clinically proven farmer's lung patients and 10 normal controls using three immunological methods. These methods were agar gel double diffusion (DD), biotin-avidin-linked immunosorbent assay (BALISA) and dot-immunobinding assay (DIBA). Agar gel diffusion, the least sensitive of the three methods, failed to detect antibodies in some of the patients, while BALISA detected antibodies even in the normal controls. However, the sensitivity of dot-immunobinding assay was in between DD and BALISA while the specificity was comparable to DD to all the antibodies except against A. fumigatus antigens. Dot-immunobinding assay gave faster results than DD and the blots can be stored as record for longer periods of time without fading.

Invasive bronchopulmonary aspergillosis leading to rapidly progressive respiratory failure in a patient with severe aplastic anemia

A 22-year-old man with severe aplastic anemia was treated with antilymphocyte globulin, prednisone, and oxymetholone. Fourteen days after initiation of treatment he developed a fulminant mediastinal and subcutaneous emphysema leading to respiratory failure refractory to mechanical ventilation. Fiberoptic bronchoscopy showed nodular lesions typical of aspergillus. Cultures of bronchial mucus revealed Aspergillus fumigatus as the responsible pathogen.

Pathogenetic and serological aspects of pulmonary aspergillosis

Af is an important pathogen of the bronchopulmonary system, and the clinical spectrum encompasses aspergilloma, CNPA, IPA, ABPA, bronchial asthma, and allergic alveolitis. Bronchial carriage may, however, not always be associated with pathological effects. The polymorphism of the aspergillus-related disorders seems mostly to depend upon the different responses of the hosts. This review considers the antigenic composition of Af and specific antibody responses in man in relation to the pathogenesis and diagnosis of the various forms of pulmonary aspergillosis. More than 200 macromolecular components have been listed for Af and more than 30 antigens found to react with human sera. Serum antibodies to Af are common in healthy subjects. Schønheyder and his associates (A-L) have shown that IgG, IgA and IgM antibodies in healthy subjects are directed towards antigens to which also patients with aspergillosis strongly react. With immunofluorescent staining these antigens were found to be associated with hyphal walls, and a MW 470,000 fraction from ruptured mycelium was most reactive in ELISA. The respiratory tract appears to be the major route for exposure since the humoral responses include IgA class antibodies, and sIgA antibodies are found in bronchial secretions. Moreover, IgG antibody levels to the MW 470,000 fraction correlate with occupational exposure and smoking habits. In patients with cystic fibrosis high IgG antibody levels to MW 470,000 and MW 25,000-50,000 antigen fractions were associated with the carriage of Af in the sputum. An individual patient's level of IgA antibodies to the MW 470,000 fraction was inversely related to the Af carrier rate, and this was also true for IgE dependent reactivity to Af antigens. These observations indicate that IgG antibodies to some antigens mirror the extent of antigenic exposure, whereas some IgA and IgE antibodies may play a protective role against bronchial colonization with Af. IgG antibody determinations by ELISA were found to provide a higher diagnostic efficacy in pulmonary aspergillosis than IgA antibody assays. With IgG antibodies there were statistically significant differences between patients and the controls and there was little overlap of ELISA values between the groups. The fractions of MW 250,000 with catalase activity and MW 25,000-50,000 with protease activity, were most suitable for serological diagnosis. A gel immunoelectrophoretic assay proved Af catalase to be a major diagnostic antigen in patients with aspergilloma or with an apical aspergillus lung infiltrate.(ABSTRACT TRUNCATED AT 400 WORDS)

Head and neck aspergillosis in patients undergoing bone marrow transplantation. Report of four cases and review of the literature

Aspergillus infection can be a major cause of morbidity in immunocompromised patients, especially when there is pulmonary involvement. Diagnosis of aspergillosis is often complicated by the varied clinical presentation and compromised medical status of such patients. Four cases of head and neck Aspergillus infections in bone marrow transplant patients are presented. Involvement predominantly was limited to the oral cavity and/or sinuses, and in one case, the ear. Two cases were successfully managed with a combined antibiotic and surgical approach, and one case with antibiotics only. The fourth case was managed with antibiotics and surgery, but fatal hemorrhage secondary to sinus involvement developed.

Host-parasite relationship in opportunistic mycoses

Aspergillosis and mucormycosis are opportunistic fungal infections that share several unique features. The etiologic agents of aspergillosis and mucormycosis are ubiquitous in the environment, but are opportunistic organisms and usually infect only patients predisposed by some underlying disease or treatment. These infections are typically characterized by hyphal tissue invasion and a predilection of the organism for blood vessel invasion with hemorrhage, necrosis, and infarction. Also, these organisms are not dimorphic, like the true pathogenic dimorphic fungi, as they grow both in the environment and within the host in hyphal forms. However, the host must contend with several forms to successfully eliminate them. Each form displays different antigenic and surface features and elicits different host responses. Finally, if germination and hyphal growth occur, the host must compete with a rapidly growing organism that is too large to be ingested by a single cell and so must be handled by extracellular defense mechanisms.

Aspergillosis of the nose and paranasal sinuses in neutropenic patients at an oncology center

Invasive aspergillosis of the nose and paranasal sinuses is one of the presentations of aspergillosis in granulocytopenic patients with neoplastic disorders. It is most prevalent among patients with leukemia and granulocytopenia and is associated with a high mortality rate. We report five cases of invasive aspergillosis of the nose and paranasal sinuses in profoundly neutropenic patients treated with broad spectrum antibiotics. Both Aspergillus fumigatus and Aspergillus flavus were cultured and identified in this entity. Awareness of this disease and early diagnosis made by culture and histologic examinations of biopsy material are essential. Treatment consisting of amphotericin B therapy and surgical debridement can be effective in eradicating this form of aspergillosis.

An outbreak of invasive aspergillosis among allogeneic bone marrow transplants: a case-control study

Between April 1982 and March 1983, 10 of 26 (38.4%) allogeneic bone marrow transplant recipients housed on a newly opened bone marrow transplant unit developed invasive aspergillosis. By contrast, between September 1977 and March 1982, only 3 of 46 (6%) transplant recipients developed invasive aspergillosis. A case-control study to identify host factors related to Aspergillus infection found that aspergillosis was more common in patients with chronic myelogenous leukemia and aplastic anemia, older patients, patients having cytomegalovirus disease, patients who experienced prolonged granulocytopenia, patients conditioned with ara-C (100-200 mg/day), and patients who received longer duration of antimicrobial therapy. A series of logistic regression analyses revealed that underlying disease was the single best predictor of Aspergillus infection. This study demonstrates that underlying disease is an important risk factor for aspergillosis and that special measures may be warranted when transplanting certain patients.

Characterization of protein and mannan polysaccharide antigens of yeasts, moulds, and actinomycetes

Antigens in coccidioidin were compared with purified subfractions via tandem immunoelectrophoresis (IEP) and by a combination of advancing line and crossed IEP. Rocket IEP was suitable for titrating the reactions and showing the relationship between column fractions. These techniques required multicomponent antisera produced by hyperimmunization over many months and by the use of known standard migration pairs. The IEP variations were used to chart the development of antisera against coccidioidin factors, to monitor antigen purifications, and to test the immunochemical homogeneity of an isolated antigen. Mannose-based heteroglycans of Cryptococcus neoformans were recovered from the culture filtrate. After precipitation of the major viscous glucuronoxylomannan (GXM) with ethanol or cetyltrimethylammonium bromide, the supernate is reserved because it contains a galactoxylomannan (GalXM). After removal of glucuronic acid from the GXM, the resulting xylomannan of serotype A was amenable to 13C-nuclear magnetic resonance (NMR) spectrometry; it revealed nonreducing xylose, alpha-1,3-mannose, and alpha-1,2/1,3 disubstituted mannose, thus confirming by an independent means what was previously known. The characterization sequence of GalXM included: (1) gas-liquid chromatography (GLC) of neutral sugars as peracetylated aldononitriles; (2) methylation-fragmentation GLC mass spectrometry to determine the glycosidic linkages; and (3) 13C-NMR showing similarities to mannan of Saccharomyces cerevisiae. Affinity chromatography of the GalXM on concanavalin A separated the galactoxylo component from an adsorbed mannoprotein. Selection of monoclonal antibodies (MAbs) relies on presumptive enzyme immunoassays (EIAs) or radioimmunoassays for rapid screening of clones and for determination of isotypes; however, higher resolution confirmatory tests are needed to obtain MAbs of desired specificity. MAbs against Candida tropicalis mannan were labeled with horseradish peroxidase to use for detecting mannan in serum. MAbs against the partially purified "m" factor of histoplasmin were characterized by the enzyme-linked immunoelectro-transfer blot technique (EITB), revealing unsuspected complexity in the antigen. Secreted proteins of Nocardia asteroides were isoelectrically focused; three proteins, identified by EITB as promising to be specific for that actinomycete, were cut out of gels and used to immunize mice for production of MAbs. The fimbriae of Actinomyces viscosus and A. naeslundii that mediate lactose-reversible coagglutination with Streptococcus sanguis have been used to evoke MAbs.(ABSTRACT TRUNCATED AT 400 WORDS)

Invasive aspergillosis of paranasal tissues in children with malignancies

Paranasal aspergillosis was encountered in five children with relapsed malignancies. All had received broad-spectrum antibiotics within two weeks of development of aspergillosis, and all had absolute granulocyte counts less than 200/mm3 for at least three weeks. None had received prior antifungal therapy. There was an average delay of eight days before the correct diagnosis was established by either biopsy or culture. These data emphasize the need to obtain surveillance cultures of the upper respiratory tract passages in severely neutropenic patients receiving prolonged antibiotic therapy, and raise a question concerning prophylactic use of antifungal therapy in this group.