Invasive aspergillosis in acute leukemia: correlation with nose cultures and antibiotic use

Prospective multicentre study on azole resistance in Aspergillus isolates from surveillance cultures in haematological patients in Italy

OBJECTIVES

This study was conducted to assess the prevalence of azole resistance in Aspergillus isolates from patients with haematological malignancies or who were undergoing haematopoietic stem cell transplantation and to identify the molecular mechanism of resistance.

METHODS

In this 28-month prospective study involving 18 Italian centres, Aspergillus isolates from surveillance cultures were collected and screened for azole resistance, and mutations in the cyp51A gene were identified. Resistant isolates were genotyped by microsatellite analysis, and the allelic profiles were compared with those of resistant environmental and clinical isolates from the same geographical area that had been previously genotyped.

RESULTS

There were 292 Aspergillus isolates collected from 228 patients. The isolates belonged mainly to the section Fumigati (45.9%), Nigri (20.9%), Flavi (16.8%) and Terrei (4.8%). Three isolates showed itraconazole resistance: Aspergillus fumigatus sensu stricto, Aspergillus lentulus (section Fumigati) and Aspergillus awamori (section Nigri). The itraconazole resistance rates were 1% and 1.48% considering all Aspergillus spp. isolates and the Aspergillus section Fumigati, respectively. The prevalence of azole resistance among all the patients was 1.3%. Among patients harbouring A. fumigatus sensu stricto isolates, the resistance rate was 0.79%. The A. fumigatus isolate, with the TR₃₄/L98H mutation, was genotypically distant from the environmental and clinical strains previously genotyped.

CONCLUSIONS

In this study, the Aspergillus azole resistance rate was 1% (3/292). In addition to A. fumigatus sensu stricto, A. lentulus and A. awamori azole-resistant isolates were identified. Therefore, it is important have a correct identification at the species level to address a rapid therapy better, quickly understand the shift towards cryptic species and have an updated knowledge of the local epidemiology.

Intracranial fungal granuloma: a single-institute study of 90 cases over 18 years

OBJECTIVE

Intracranial fungal granuloma (IFG) remains an uncommon entity. The authors report a single-institute study of 90 cases of IFG, which is the largest study until now.

METHODS

In this retrospective study, all cases of IFG surgically treated in the years 2001-2018 were included. Data were obtained from the medical records and the pathology, microbiology, and radiology departments. All relevant clinical data, imaging characteristics, surgical procedure performed, perioperative findings, and follow-up data were recorded from the case files. Telephonic follow-up was also performed for a few patients to find out their current status.

RESULTS

A total of 90 cases consisting of 64 males (71.1%) and 26 (28.9%) females were evaluated. The mean patient age was 40.2 years (range 1-79 years). Headache (54 patients) was the most common presenting complaint, followed by visual symptoms (35 patients), fever (21 patients), and others such as limb weakness (13 patients) or seizure (9 patients). Cranial nerve involvement was the most common sign (47 patients), followed by motor deficit (22 patients) and papilledema (7 patients). The mean duration of symptoms before presentation was 6.4 months (range 0.06-48 months). Thirty patients (33.3%) had predisposing factors like diabetes mellitus, tuberculosis, or other immunocompromised status. A pure intracranial location of the IFG was seen in 49 cases (54.4%), whereas rhinocerebral or paranasal sinus involvement was seen in 41 cases (45.6%). Open surgery, that is, craniotomy and decompression, was performed in 55 cases, endoscopic biopsy was done in 30 cases, and stereotactic biopsy was performed in 5 cases. Aspergilloma (43 patients) was the most common fungal mass, followed by zygomycosis (13 patients), chromomycosis (9 patients), cryptococcoma (7 patients), mucormycosis (5 patients), and candida infection (1 patient). In 12 cases, the exact fungal phenotype could not be identified. Follow-up was available for 69/90 patients (76.7%). The mean duration of the follow-up was 37.97 months (range 3-144 months). The mortality rate was 52.2% (36/69 patients) among the patients with available follow-up.

CONCLUSIONS

A high index of suspicion for IFG should exist for patients with an immunocompromised status and diabetic patients with rhinocerebral mass lesions. Early diagnosis, aggressive surgical decompression, and a course of promptly initiated antifungal therapy are associated with a better prognosis.

Pathophysiological aspects of Aspergillus colonization in disease

Aspergillus colonization of the lower respiratory airways is common in normal people, and of little clinical significance. However, in some patients, colonization is associated with severe disease including poorly controlled asthma, allergic bronchopulmonary aspergillosis (ABPA) with sputum plugs, worse lung function in chronic obstructive pulmonary aspergillosis (COPD), invasive aspergillosis, and active infection in patients with chronic pulmonary aspergillosis (CPA). Therefore, understanding the pathophysiological mechanisms of fungal colonization in disease is essential to develop strategies to avert or minimise disease. Aspergillus cell components promoting fungal adherence to the host surface, extracellular matrix, or basal lamina are indispensable for pathogen persistence. However, our understanding of individual differences in clearance of A. fumigatus from the lung in susceptible patients is close to zero.

Incidence of Nosocomial Aspergillosis in Patients with Leukemia Over a Twenty-Year Period

The incidence of invasive nosocomial aspergillosis was studied in leukemia patients at an oncology center from 1964 to 1983. A total of 97 cases of aspergillosis occurred in 1,866 patients, yielding an overall case rate of 5.2 cases per 100 patients and an incidence rate of 9.1 per 10,000 patient days. The highest incidence rate was in patients with chronic myelogenous leukemia (13.7 cases per 10,000 patient days), followed by patients with acute myelogenous leukemia (10.6 cases per 10,000 patient days). Subdividing patients after 1978 into those receiving bone marrow transplantation and those who did not demonstrated the predisposition of transplant recipients to aspergillosis. The rates of aspergillosis among those patients who did not receive a bone marrow transplant were highest for patients with acute myelogenous leukemia. Increases in the annual rates of aspergillosis over time coincided with the level of internal renovation activity and major construction projects upwind of patient care facilities.

Oral Candida infection and colonization in solid organ transplant recipients

INTRODUCTION

Oral Candida carriage and infection have been reported to be associated with a greater risk for systemic infection in transplant recipients; however, a systematic analysis of the oral Candida titers and species has not been previously conducted. The objectives of this study were to determine the prevalence of oropharyngeal candidiasis, the oral carrier status, Candida titers and species in this population.

METHODS

Ninety kidney and heart transplant subjects and 72 age-matched healthy controls were included. Swabs from the oral mucosa and a standardized amount of unstimulated saliva were plated on Chromagar Candida, and colony-forming units per millilitre were calculated. Initial speciation was based on colony color and was confirmed by standard germ tube, biotyping, or polymerase chain reaction assays.

RESULTS

Infection with C. albicans was detected in seven transplant subjects and none of the controls. The transplant group had significantly higher oral Candida titers than the control group. There were no statistically significant relationships between the dose or type of immunosuppressants and oral Candida titers or infection. A significantly higher percentage of transplant subjects were colonized by more than one species, compared with control subjects. The most frequent species combination in transplant subjects was C. albicans and C. glabrata. C. glabrata was isolated from 13.5% of transplant carriers and none of the controls.

CONCLUSIONS

Increased oral Candida infection and carriage titers were found in the transplant population. Although the majority of transplant patients were colonized by C. albicans, C. glabrata appears to emerge as the second most prevalent species.

Invasive Aspergillus infections in allo-SCT recipients: environmental sampling, nasal and oral colonization and galactomannan testing

A study was performed to investigate the air quality of a haematopoietic SCT ward, colonization of the upper airways with Aspergillus spp. and the role of galactomannan (GM) ELISA testing in serum in the diagnosis of invasive aspergillosis (IA). In 102 allo-SCT recipients, two cases of IA (one proven and one probable) were seen. Of 2071 serum samples, 12 were positive, two in a patient with proven IA and 10 in patients without IA. Of the 2059 negative samples, 22 were taken from the patient with probable IA. Of the 245 environmental samples, 20 (8.2%) were positive for filamentous fungi. Aspergillus fumigatus was seen in 14 samples. A total of 657 oral and nasal swabs were taken. Seven nasal samples and one oral sample were positive for Aspergillus species (A. fumigatus 4, A. niger 4) in four patients, one of whom had probable IA. In summary, most environmental samples were negative, colonization of the oral and nasal cavities was rare and IA was diagnosed in only 2% of patients. The GM ELISA test remained negative in one of two patients with IA and does not seem useful in a population of patients with a low incidence of IA.

The utility of intensified environmental surveillance for pathogenic moulds in a stem cell transplantation ward during construction work to monitor the efficacy of HEPA filtration

A 12-week environmental study was performed to ensure that the patient rooms of an SCT ward with high-efficiency particulate air (HEPA) filtration remained uncontaminated by moulds during close-by construction work. The sampling included measuring the ventilation channel pressure, particle count measurements, air sampling, settled dust analysis and fungal cultures from the oral and nasal cavities of the patients. No changes in the air pressure occurred. Median particle counts in patient rooms were 63-420 particles/l. The mean particle count of the outside air was 173,659 particles/l. Patient room air samples were negative for aspergilli in 32 of 33 cases. All samples of the outside air were positive for moulds. Aspergillus fumigatus was isolated at the beginning of excavation works at the construction area and in two of 33 dust samples from patient rooms. All 70 nasal samples were negative. Of 35 mouth samples, one sample was positive for A. niger in a patient with a previously diagnosed aspergillus infection. During a median follow-up of 214 days, no invasive aspergillus infections were diagnosed in the 55 patients treated during the construction period. In conclusion, the HEPA filters seemed to have performed well in preventing an aspergillosis outbreak.

Interleukin-10 promoter polymorphism as risk factor to develop invasive pulmonary aspergillosis

This present study was undertaken to examine the role of the host response to Aspergillus fumigatus in the development of clinical symptoms of invasive pulmonary aspergillosis (IPA). The natural outcome and response to IPA infection varies between individuals. Whereas some variation may be attributable to fungi and environmental variables, it is probable that host genetic background also plays a significant role. Interleukin (IL)-10 has a key function in the regulation of cellular immune responses and is involved in various inflammatory diseases. IL-10 promoter carries a polymorphism that has been associated to production levels. Our aim was to investigate the role of this polymorphism in susceptibility to develop IPA infection. The study included 120 haematological patients and 124 age and sex-matched controls and bi-allelic IL-10 -1082(G/A) polymorphism was examined. Genotypic (p=0.385) and allelic frequencies (p=0.527, OR=0.89, 95% CI=0.78-1.60) were similar between patients and healthy controls. IPA was diagnosed in 59 of the 120 patients according to consensus criteria published by the European Organization for Research and Treatment of Cancer/Invasive Fungal Infections Cooperative Group (EORTC/IFICG). Our results provide evidence that IL-10 -1082(AA) genotype is associated with resistance to develop IPA (p=0.001). Allele frequency of IL-10 -1082A allele was weakly associated with susceptibility to develop IPA infection (p=0.052). In conclusion, these results suggest that differential production of IL-10 may alter the risk for IPA in haematological patients.

Variable Number of Tandem Repeats of TNF Receptor Type 2 Promoter as Genetic Biomarker of Susceptibility to Develop Invasive Pulmonary Aspergillosis

Tumor necrosis factor alpha (TNF-alpha) and lymphotoxin alpha (LT-alpha) are pivotal mediators of inflammatory responses in fungal infection diseases. We hypothesized that polymorphisms in genes of these cytokines or their receptors might increase the susceptibility of hematologic patients to develop invasive pulmonary aspergillosis (IPA). One hundred two hematologic patients and 124 age-matched controls were enrolled in the study, and the following standard single nucleotide polymorphisms were investigated: TNF-alpha -308 and +489, LT-alpha +252 and Tumor Necrosis Factor Receptor 2 (TNFR2) +676. Variable number of tandem repeats (VNTRs) at position -322 of the TNFR2 gene were also studied. Genotypic and allelic frequencies were similar between patients and controls. IPA was diagnosed in 54 of the 102 patients according to consensus criteria published by the European Organization for Research and Treatment of Cancer/Invasive Fungal Infections Cooperative Group. TNF-alpha and LT-alpha polymorphisms were not associated with presence of IPA. Susceptibility to IPA was strongly associated with VNTR at position -322 in the promoter region of the TNR2 gene (p = 0.029) but was not associated with the presence of TNFR2 +676 polymorphism. A genetic difference in TNFR2 promoter VNTR may play a major role in susceptibility to IPA infection.

Clinical relevance of Aspergillus isolation from respiratory tract samples in critically ill patients

Introduction

The diagnosis of invasive pulmonary aspergillosis, according to the criteria as defined by the European Organisation for the Research and Treatment of Cancer/Mycoses Study Group (EORTC/MSG), is difficult to establish in critically ill patients. The aim of this study is to address the clinical significance of isolation of Aspergillus spp. from lower respiratory tract samples in critically ill patients on the basis of medical and radiological files using an adapted diagnostic algorithm to discriminate proven and probable invasive pulmonary aspergillosis from Aspergillus colonisation.

Methods

Using a historical cohort (January 1997 to December 2003), all critically ill patients with respiratory tract samples positive for Aspergillus were studied. In comparison to the EORTC/MSG criteria, a different appreciation was given to radiological features and microbiological data, including semiquantitative cultures and direct microscopic examination of broncho-alveolar lavage samples.

Results

Over a 7 year period, 172 patients were identified with a positive culture. Of these, 83 patients were classified as invasive aspergillosis. In 50 of these patients (60%), no high risk predisposing conditions (neutropenia, hematologic cancer and stem cell or bone marrow transplantation) were found. Typical radiological imaging (halo and air-crescent sign) occurred in only 5% of patients. In 26 patients, histological examination either by ante-mortem lung biopsy (n = 10) or necropsy (n = 16) was performed, allowing a rough estimation of the predictive value of the diagnostic algorithm. In all patients with histology, all cases of clinical probable pulmonary aspergillosis were confirmed (n = 17). Conversely, all cases classified as colonisation had negative histology (n = 9).

Conclusion

A respiratory tract sample positive for Aspergillus spp. in the critically ill should always prompt further diagnostic assessment, even in the absence of the typical hematological and immunological host risk factors. In a minority of patients, the value of the clinical diagnostic algorithm was confirmed by histological findings, supporting its predictive value. The proposed diagnostic algorithm needs prospective validation.

Clinical implications of environmental sources for Aspergillus

Invasive aspergillosis presents a formidable problem for both diagnosis and therapy. Therefore, prevention is a very important strategy in controlling this disease. Preventing invasive aspergillosis demands a clear understanding of the environmental sources of Aspergillus spp. and how this mould is transmitted to patients. Insight into the sources of exposure, mechanisms of transmission, and host susceptibility to infection are vital to appropriately direct preventive strategies to those settings where the risk of infection is the highest and consequently the impact of prevention the greatest.

Intracranial fungal granuloma: analysis of 40 patients and review of the literature

OBJECTIVE

To describe the characteristics of patients diagnosed with intracranial fungal granuloma (IFG) in the largest reported series to date (to our knowledge).

METHODS

A 22-year retrospective, multi-institutional review of 40 patients, aged 16 to 62 years (mean, 40.2 years), was performed in patients with histopathologically confirmed IFG. The variables were symptoms/signs at presentation, predisposing factors, location of granuloma, involvement of paranasal sinuses, diagnostic studies including blood and urine cultures, surgical procedures performed, specific organism identified, treatment, and prognosis. Plain x-rays, computed tomography, and/or magnetic resonance imaging scans were performed.

RESULTS

Predominant symptoms included headache (83%), vomiting (65%), proptosis (48%), and visual disturbances (48%). Other symptoms were fever, nasal congestion, and seizures (7 [18%]). Common signs included papilledema (12 [30%]), with cranial neuropathy (I, III/IV/VI, and V in 4, 7, and 2 patients, respectively), hemiparesis (3), and meningismus (3). Predisposing factors were diabetes (16 [40%]), tuberculosis (7 [18%]), and immunocompromise related to renal transplant (2), non-Hodgkin's lymphoma (1), and human immunodeficiency virus (1). Location was primarily frontal (10 [25%]), with anterior cranial fossa involved in 8 (20%) patients; 6 (15%) patients had sellar/parasellar involvement. Eighteen (40%) had paranasal sinus involvement. Twenty-nine patients underwent craniotomy for resection, with 11 undergoing biopsy (of which 3 were transsphenoidally approached). Histopathology revealed aspergilloma (25 [63%]), mucormycosis (7 [18%]), cryptococcoma (3), cladosporidium (3), Bipolaris hawaiiensis (1), and Candida species(1). Microbiological analysis of the specimen was positive in 28 (60%) patients. All patients were treated with amphotericin B, fluconazole, and/or flucytosine. Only 26 patients completed amphotericin B therapy (due to nephrotoxicity). Mortality was 63%, most commonly due to meningoencephalitis (16 [36%]).

CONCLUSIONS

High index of suspicion of IFG should exist for the following groups: (1) immunocompromised patients with intracranial lesions and (2) diabetic patients with intracranial and rhinocerebral mass lesions. Early diagnosis, surgical decompression, and a complete course of promptly initiated antifungal therapy are associated with better prognosis.

Long-term antifungal prophylaxis in high-risk hematopoietic stem cell transplant recipients

The risks for invasive fungal infections, particularly mould infections such as invasive aspergillosis, among hematopoietic stem cell transplant (HSCT) recipients are linked to the duration and severity of myelosuppression and immunosuppression. Strategies to prevent invasive fungal infections have focused primarily on the use of orally administered azole antifungal agents during the neutropenic period rather than on the more prolonged post-engraftment period. The major limitations of these studies included the heterogeneity among the subjects studied for fungal infection risk factors, the agents administered, the dosing, and duration of prophylaxis. More recent studies have attempted to examine the efficacy of antifungal prophylaxis strategies among allogeneic HSCT recipients to day 100 and beyond. It is clear that a variety of products have efficacy in preventing invasive candidiasis, including imidazole and triazole antifungals, low-dose amphotericin B, and the echinocandin, micafungin; however, only the extended spectrum azole, itraconazole, has been shown to impact the incidence of proven invasive aspergillosis. Other extended spectrum azole antifungal agents, voriconazole and posaconazole, are being studied as long-term prophylaxis in high-risk HSCT recipients. While clinical trials have suggested that a duration of prophylaxis against moulds of six months or more may be required, it remains unclear if this is required in all cases. The prophylactic efficacy over time may be linked to the degree of immunosuppression as measured by markers such as the numbers of circulating CD4 T lymphocytes. Concerns about selection for resistant moulds among long-term recipients of these drugs are emerging. The cumulative experience to date suggests that long-term antifungal chemoprophylaxis is feasible and effective when applied in defined circumstances. The concerns about treatment-related toxicities, resistance, and costs are valid.

Aspergillose pulmonaire invasive chez les enfants immunodeṕrimés méthodes diagnostiques et classification

Invasive aspergillosis is an opportunistic infection, with frequent lung involvement. High-risk children are allogenic bone marrow recipients, and those with hematological malignancies, aplastic anemia or chronic granulomatous disease. Profound and prolonged neutropenia, and corticosteroid therapy are the most important predisposing factors. Building and demolition works represent the major environmental risk factor. The diagnosis of invasive aspergillosis remains difficult to establish. Clinical manifestations are non-specific. Early thoracic computed tomographic scan shows halo sign in most cases. Subsequently appears the air crescent sign. Galactomannan research by sandwich ELISA can be useful in serum and in bronchoalveolar lavage fluid. Aspergillus DNA detection by PCR is still not standardized. Culture of the organism allows species identification. Aspergillus hyphae can be found at cytological examination, but a biopsy specimen is usually required to affirm tissue damage. A new classification of invasive fungal infections in immunocompromised patients was recently proposed by experts from the European Organization for Research and Treatment of Cancer and from the Mycoses Study Group of the National Institute of Allergy and Infectious Diseases. On the basis of host linked criteria, microbiological, clinical and radiological features, invasive aspergillosis is classified as proven, probable or possible. These definitions should not be used to guide clinical practice in therapy, but they will improve the quality of epidemiological data, and help the comparison of clinical trial results.

Antifungal prophylaxis for severely neutropenic chemotherapy recipients: a meta analysis of randomized-controlled clinical trials

BACKGROUND

The overall clinical efficacy of the azoles antifungal agents and low-dose intravenous amphotericin B for antifungal chemoprophylaxis in patients with malignant disease who have severe neutropenia remains unclear.

METHODS

Randomized-controlled trials of azoles (fluconazole, itraconazole, ketoconazole, and miconazole) or intravenous amphotericin B formulations compared with placebo/no treatment or polyene-based controls in severely neutropenic chemotherapy recipients were evaluated using meta-analytical techniques.

RESULTS

Thirty-eight trials that included 7014 patients (study agents, 3515 patients; control patients, 3499 patients) were analyzed. Overall, there were reductions in the use of parenteral antifungal therapy (prophylaxis success: odds ratio [OR], 0.57; 95% confidence interval [95% CI], 0.48-0.68; relative risk reduction [RRR], 19%; number requiring treatment for this outcome [NNT], 10 patients), superficial fungal infection (OR, 0.29; 95% CI, 0.20-0.43; RRR, 61%; NNT, 12 patients), invasive fungal infection (OR, 0.44; 95% CI, 0.35-0.55; RRR, 56%; NNT, 22 patients), and fungal infection-related mortality (OR, 0.58; 95% CI, 0.41-0.82; RRR, 47%; NNT, 52 patients). Invasive aspergillosis was unaffected (OR, 1.03; 95% CI, 0.62-1.44). Although overall mortality was not reduced (OR, 0.87; 95% CI, 0.74-1.03), subgroup analyses showed reduced mortality in studies of patients who had prolonged neutropenia (OR, 0.72; 95% CI, 0.55-0.95) or who underwent hematopoietic stem cell transplantation (HSCT) (OR, 0.77; 95% CI, 0.59-0.99). The multivariate metaregression analyses identified HSCT, prolonged neutropenia, acute leukemia with prolonged neutropenia, and higher azole dose as predictors of treatment effect.

CONCLUSIONS

Antifungal prophylaxis reduced morbidity, as evidenced by reductions in the use of parenteral antifungal therapy, superficial fungal infection, and invasive fungal infection, as well as reducing fungal infection-related mortality. These effects were most pronounced in patients with malignant disease who had prolonged neutropenia and HSCT recipients.

Environmental surveillance and other control measures in the prevention of nosocomial fungal infections

The steady world-wide increase in the number of severely immunocompromised patients in most hospitals has made the control and prevention of nosocomial systemic fungal infections a critical quality-of-care standard. Early diagnosis and antifungal prophylaxis of these infections are complicated, so avoiding the acquisition of the pathogen in the case of Aspergillus and minimizing the predisposing risk factors in the case of Candida are more effective approaches. The maintenance of good air quality in critical areas in hospitals is mandatory to reduce the incidence of invasive aspergillosis. We review the currently available Center for Disease Control recommendations and report our own experiences in the field. The indications and problems of fungal environmental and patient surveillance are also discussed.

Usefulness of bacteriological surveillance cultures for monitoring infection in hospitalized patients: a critical reappraisal

Untargeted bacteriological surveillance of superficial and deep body sites is frequently performed routinely in various clinical settings. This practice is based on the assumption that early identification of surface microbial flora might be predictive of organisms that will later cause invasive disease and that it may consequently assist in guiding empirical antibiotic therapy. A comprehensive review of the literature however indicates that the clinical value and cost-effectiveness of such practices still remain debated and appear largely unproven in most conditions and situations where they are routinely advocated. The present article reviews and critically discusses the available body of evidence supporting or disproving the use of bacteriological surveillance cultures. It is also aimed to issue general recommendations, strategies and methodologies that could be applied in different hospital care settings including the neonatal or adult intensive care as well as the hematology-oncology units.

Cutaneous and paranasal aspergillosis in an immunocompetent patient

A 26-year-old Libyan woman presented with asymptomatic nodulo-ulcerative skin lesions present for 1 year. Three years prior to presentation, she had experienced a nasal discharge followed by the development of a nodule in the nasal cavity and a plaque on the hard palate. These lesions had gradually increased in size and ulcerated, resulting in perforation of the nasal septum and palate. Two years later, the patient noticed the appearance of skin lesions: a nodule on the right thumb and numerous nodulo-ulcerative lesions on the extremities. General physical examination was normal with no significant lymphadenopathy. Examination of the oral cavity revealed perforation of the distal nasal septum, with a perforated nodular plaque involving the entire palate, associated with subluxation of the upper incisors (Fig. 1a). On skin examination, multiple firm nodules and nodulo-ulcerative lesions with a central eschar and raised margins were observed. The lesions ranged in size from 0.5 to 5 cm and were distributed on the right hand and fingers, left upper arm (Fig. 1b), left calf, and right thigh. Routine laboratory investigations (liver function tests, serum calcium, electrolytes, lipid profile, urine and stool culture studies) were normal. Immunoelectrophoresis disclosed normal levels of immunoglobulins IgG, IgA, and IgM. Serologic studies for human immunodeficiency virus (HIV) and syphilis, and a tuberculin test, were all negative. A Giemsa-stained tissue smear was negative for Leishmania tropica organisms. Radiological studies disclosed a slight haziness of the maxillary sinuses with perforation of the nasal septum. A chest X-ray was normal. Histopathologic examination of biopsies taken from both the palate and from ulcerated and nonulcerated skin lesions was performed, and all showed similar findings. The biopsy of a nonulcerated skin lesion showed pseudoepitheliomatous epidermal hyperplasia with neutrophilic microabscesses (Fig. 2a). A dermal diffuse and nodular granulomatous mixed infiltrate of lymphocytes, histiocytes, giant cells, numerous eosinophils, and neutrophilic microabscesses was seen in all tissues examined. Septate hyphae were present both within giant cells and free in the dermis (Fig. 2b). The hyphae were branching at a 45 degrees angle and were positive on periodic acid-Schiff and Grocott methenamine silver stains (Fig. 2c). Fungal culture studies of material taken from an ulcerated skin lesion grew Aspergillus flavus. Blood cultures were negative for Aspergillus sp. or other microorganisms. The patient was treated with intravenous amphotericin B, but the medication was discontinued due to her intolerance to the drug. She was subsequently lost to follow-up.

Fatal invasive cerebral Absidia corymbifera infection following bone marrow transplantation

A 56-year-old dairy farmer received a fully HLA matched unrelated donor marrow transplant for high risk CML in chronic phase. His early post-transplant course was complicated by a series of massive intracerebral bleeds and by sepsis related to a malignant otitis externa. The microbial pathogen isolated from ear swabs was found to be Absidia corymbifera, but CT scan at the time showed no intracerebral extension. Despite neutrophil engraftment and aggressive antifungal management he succumbed. Autopsy revealed invasion of Absidia into the brain from the ear. We speculate that colonisation by Absidia resulted from occupational exposure.

Medical management of Aspergillus flavus endocarditis

An 11-year-old boy underwent a matched unrelated bone marrow transplant for refractory acute myeloid leukemia. He developed invasive aspergillus pneumonia and endocarditis post-transplant. The fungal endocarditis was successfully eradicated with liposomal amphotericin at the dose of 10 mg/kg/day. Surgical intervention was not required and no serious side effects of liposomal amphotericin were observed at this dose.

A prospective study on factors influencing aspergillus spore load in the air during renovation works in a neonatal intensive care unit

The relationship between air contamination (cfu/m(3)) with fungal spores, especially Aspergillus spp., in three renovation areas of a neonatal intensive care unit (NICU) and colonization and infection rates in a high care area (HC) equipped with high efficiency particulate air (HEPA) filtration and a high pressure system, was evaluated. Data on the type and site of renovation works, outdoor meteorological conditions, patient crowding and nasopharyngeal colonization rate were collected. Factors not associated with Aspergillus spp. concentration were outdoor temperature, air pressure, wind speed, humidity, rainfall, patient density in the NICU, renovation works in the administrative area and in the isolation rooms. Multivariate analysis revealed that renovation works and air concentration of Aspergillus spp. spores in the medium care area (MC) resulted in a significant increase of the concentration in the HC of the NICU. The use of a mobile HEPA air filtration system (MedicCleanAir(R)Forte, Willebroek, Belgium) caused a significant decrease in the Aspergillus spp. concentration. There was no relationship between Aspergillus spp. air concentration and nasopharyngeal colonization in the neonates. Invasive aspergillosis did not occur during the renovation. This study highlights the importance of optimal physical barriers and air filtration to decrease airborne fungal spores in high-risk units during renovation works. The value of patient surveillance and environmental air sampling is questionable since no relationship was found between air contamination and colonization in patients.

Aspergillosis in bone marrow transplant recipients

Invasive aspergillosis in bone marrow transplant recipient is associated with a high mortality. Diagnosis is often delayed because the inflammatory response is blunted by immunosuppression. The gold standard of tissue biopsy is often considered too in invasive as the procedure is often complicated by bleeding and secondary infection. Recent finding on non-invasive tests such as serial measurement of peripheral blood galactomannan antigen or DNA appears to be promising. However, the limited availability of such tests and requirement for expertise are still hampering their use in routine clinical management. More often than not, initiation of antifungal therapy is empirical and based on suggestive radiological changes. Amphotericin B remains the gold standard of therapy but liposconal preparation may prove to be less nephrotoxic and equally effective. Treatment outcome depends more on the acceleration of the recovery of the immune system and the reduction of anti-GVHD therapy than the antifungal agent followed by surgical resection. The efficacy of many reported anti-aspergillosis prophylactic regimen has not been proved in randomized control trials. Despite the absence of data, such policy should still be considered in transplant units with high incidence of aspergillus or undergoing renovation.

Fusarium infections of the skin

Fusarium species are ubiquitous and may be found in the soil, air and on plants. Fusarium species can cause mycotoxicosis in humans following ingestion of food that has been colonized by the fungal organism. In humans, Fusarium species can also cause disease that is localized, focally invasive or disseminated. The pathogen generally affects immunocompromised individuals with infection of immunocompetent persons being rarely reported. Localized infection includes septic arthritis, endophthalmitis, osteomyelitis, cystitis and brain abscess. In these situations relatively good response may be expected following appropriate surgery and oral antifungal therapy. Disseminated infection occurs when two or more noncontiguous sites are involved. Over eighty cases have been reported, many of which had a hematologic malignancy including neutropenia. The species most commonly involved include Fusarium solani, Fusarium oxysporum, and Fusarium moniliforme (also termed F. verticillioides). The diagnosis of Fusarium infection may be made on histopathology, gram stain, mycology, blood culture, or serology. Portals of entry of disseminated infection include the respiratory tract, the gastrointestinal tract, and cutaneous sites.The skin can be an important and an early clue to diagnosis since cutaneous lesions may be observed at an early stage of the disease and in about seventy-five cases of disseminated Fusarium infection. Typical skin lesions may be painful red or violaceous nodules, the center of which often becomes ulcerated and covered by a black eschar. The multiple necrotizing lesions are often observed on the trunk and the extremities. Onychomycosis most commonly due to F. oxysporum or F. solani has been reported. The onychomycosis may be of several types: distal and lateral subungual (DLSO), white superficial (WSO), and proximal subungual (PSO). In proximal subungual onychomycosis there may be associated leukonychia and/or periungual inflammation. Patients with Fusarium onychomycosis have been cured following therapy with itraconazole, terbinafine, ciclopirox olamine lacquer, or topical antifungal agent. In other instances nail avulsion plus antifungal therapy has been successful. In patients with hematologic malignancy or bone marrow transplant, who may experience prolonged or severe neutropenia during the course of therapy, the skin and nails should be carefully examined and consideration given to treating potential infection sites that may serve as portals for systemic dissemination. When disseminated Fusarium infection is present therapy with antifungal agents has generally been disappointing with the chances of a successful resolution being enhanced if the neutropenia can be corrected in a timely manner.

A polymerase chain reaction 'PCR' for a quick diagnosis of aspergillosis

A polymerase chain reaction (PCR) was developed from sequencing data generated from a specific target band that is unique for Aspergillus fumigatus DNA digested with EcoR1. The target band was detected through Southern blot hybridization of a non-radioactive probe labelled with DIG-dUTP and DNAs of different aspergilli. The DNA of the target band was purified, concentrated and subjected to sequencing. The size of the sequenced band was approximately 445 bp. One pair of primers was designed and synthesized from the sequencing data of the band. The oligonucleotide primers were specific in amplifying an identical band of A. fumigatus in a population mix containing DNAs of different Aspergillus spp.; Pencillium spp.; yeasts; bacterial and viral organisms that are commonly encountered in clinical specimens of respiratory origin. The reaction proved highly sensitive and as little as 0.0001 microgram of A. fumigatus DNA was detected in the reaction.

Oral complications associated with immunosuppression and cancer therapies

The oral manifestations of oropharyngeal infection in immunocompromised patients present a particular challenge for both medical and dental professionals because clinical signs and symptoms may be minimal and accurate diagnosis and appropriate treatment may be difficult. Effective control of infection and management of oral symptoms are important and may be achieved by the judicious use of topical and systemic agents and by maintaining good oral hygiene. Prevention of mucosal breakdown, suppression of microbial colonization, control of viral reactivation, and effective management of severe xerostomia are all critical steps to reduce the overall morbidity and mortality of oromucosal infections in the severely immunocompromised patient.

Predictive value of a positive nasal swab for Aspergillus sp. in the diagnosis of invasive aspergillosis in adult neutropenic cancer patients

To evaluate the value of a positive nasal swab for Aspergillus in the diagnosis of invasive aspergillosis, we prospectively evaluated nasal colonization in 173 episodes of neutropenia in 92 patients with hematological malignancies. Weekly nasal swabs were taken, and the patients were followed until death or resolution of neutropenia. The outcome variables were the development of invasive aspergillosis, empirical antifungal therapy and death. In 31 episodes of neutropenia (18%) there was at least one positive nasal swab for Aspergillus sp. Only two patients developed invasive aspergillosis, both with a positive nasal swab (p = 0.03). The positive and negative predictive values of a nasal swab were 6.4% and 100%, respectively. There was no difference between patients with positive or negative swabs regarding antifungal therapy or death. In this population of patients, a nasal swab for Aspergillus sp. had a low positive predictive value and a high negative predictive value for invasive aspergillosis.

Fungal surveillance cultures during antifungal prophylaxis with itraconazole in neutropenic patients with acute leukaemia

Fungal colonization has been associated with an increased rate of invasive fungal infections in neutropenic patients. This study evaluates weekly fungal surveillance cultures from the oropharyngeal and perianal space as well as other suspected sites in 219 courses of myelosuppressive chemotherapy with itraconazole antifungal prophylaxis in 116 neutropenic patients with acute leukaemia. Itraconazole was given from the start of chemotherapy in one of six different dosing regimens. Fungal colonization occurred in 68 (31%) of courses, which was lower than in a historical control group without prophylaxis (53%, P = 0.004). Twenty-six per cent of these 116 isolates had a growth rate of more than 50 colony forming units (CFU) per culture. Candida glabrata (51%), Candida albicans (18%) and Candida krusei (4%) were the most frequently isolated species. Higher median itraconazole trough concentrations were associated with a lower growth rate in the cultures (< or = 50 CFU/culture versus > 50 CFU/culture): 710 (430-1180) ng ml-1 versus 900 (560-1650) ng ml-1 (P = 0.015). The use of itraconazole solution--compared with capsules--led to a reduced growth rate (P = 0.035). In conclusion, compared with historical controls itraconazole antifungal prophylaxis reduces the incidence and the extent of fungal colonization during neutropenia in patients with acute leukaemia.

Epidemiology of nosocomial fungal infections: invasive aspergillosis and the environment

The incidence rates of invasive aspergillosis have increased dramatically during the last two decades, and, despite all diagnostic and therapeutic efforts, outcome is often fatal. Therefore, preventive measures are of major importance in the control of invasive aspergillosis, and require full understanding of the epidemiology of this devastating disease. The environment has been suggested to play a crucial role in the epidemiology of invasive aspergillosis. Aspergillus spores are released in the air and may remain airborne for prolonged periods. As a result, spores are ubiquitously found in air and contaminate anything in contact with air. It has been hypothesized that the inhalation of airborne Aspergillus spores, either directly or through intermediate nasopharyngeal colonization, is a direct cause of pulmonary infection in immunocompromised patients. Recently, water has been suggested as an additional source of "airborne" Aspergillus spp. This review summarizes the current knowledge on the role of the environment in the epidemiology of invasive aspergillosis.

Aspergillus fumigatus and aspergillosis

Aspergillus fumigatus is one of the most ubiquitous of the airborne saprophytic fungi. Humans and animals constantly inhale numerous conidia of this fungus. The conidia are normally eliminated in the immunocompetent host by innate immune mechanisms, and aspergilloma and allergic bronchopulmonary aspergillosis, uncommon clinical syndromes, are the only infections observed in such hosts. Thus, A. fumigatus was considered for years to be a weak pathogen. With increases in the number of immunosuppressed patients, however, there has been a dramatic increase in severe and usually fatal invasive aspergillosis, now the most common mold infection worldwide. In this review, the focus is on the biology of A. fumigatus and the diseases it causes. Included are discussions of (i) genomic and molecular characterization of the organism, (ii) clinical and laboratory methods available for the diagnosis of aspergillosis in immunocompetent and immunocompromised hosts, (iii) identification of host and fungal factors that play a role in the establishment of the fungus in vivo, and (iv) problems associated with antifungal therapy.

Sinusitis in the Immunocompromised Host

Sinusitis occurs in a wide range of immunocompromised hosts, including neutropenic patients, diabetic patients, patients in critical care units, and patients with HIV infection. Reversal of underlying risk factors, such as neutropenia or diabetic ketoacidosis, is essential in the treatment of fungal rhinosinusitis. Aggressive surveillance, high clinical suspicion, and early diagnosis and treatment are all critical aspects of sinusitis management. Sinusitis is increasingly recognized as the cause of occult cases of fever in critical care patients. Sinusitis in HIV-infected patients becomes more prevalent as immunosuppression worsens.

Pulmonary aspergillosis and invasive disease in AIDS: review of 342 cases

Aspergillosis is an infrequent but commonly fatal infection among HIV-infected individuals. We review 342 cases of pulmonary Aspergillus infection that have been reported among HIV-infected patients, with a focus on invasive disease. Invasive pulmonary aspergillosis usually occurs among patients with <50 CD4 cells/mm3. Major predisposing conditions include neutropenia and steroid treatment. Fever, cough, and dyspnea are each present in >60% of the cases. BAL is often suggestive, but biopsy specimens are necessary for definite diagnosis. Amphotericin B is the mainstay of treatment and mortality is > 80%. Avoiding neutropenia and judicious use of steroids may be helpful in prevention. Aggressive diagnostic approach, early initiation of treatment, adequate dosing of antifungals, and close follow-up may improve the currently dismal prognosis.

Molecular typing of environmental and patient isolates of Aspergillus fumigatus from various hospital settings

Fingerprinting of more than 700 clinical and environmental isolates of Aspergillus fumigatus from four differential hospital settings was undertaken with a dispersed repeated DNA sequence. The analysis of the environmental isolates showed that the airborne A. fumigatus population is extremely diverse, with 85% of the strains being represented as a single genotype isolated once. The remaining 15% of the strains were isolated several times and were able to persist for several months in the same hospital environment. No strains were found to be associated with a specific location inside the hospital, and identical strains were isolated from different buildings of the hospital and outdoors. Isolation of the same strain both from patients and from the environment of the same hospital is highly suggestive of a nosocomial infection. The characteristics of the environmental fungal population explains the two main results obtained from the typing of the clinical isolates: (i) the absence of a common strain responsible for an invasive aspergillosis outbreak results from the extreme diversity of the environmental population of A. fumigatus in contact with the patients, and (ii) patients hospitalized in different wards of the same hospital can be infected with the same strain since every patient might inhale the same spore population.

The epidemiology and prevention of invasive aspergillosis

Over the past two decades, the incidence of invasive aspergillosis (IA) has risen inexorably. This is almost certainly the consequence of the more widespread use of aggressive cancer chemotherapy regimens, the expansion of organ transplant programmes and the advent of the acquired immunodeficiency syndrome (AIDS) epidemic. Despite the development of new approaches to therapy, IA still remains a life-threatening infection in immunocompromised patients and is the most important cause of fungal death in cancer patients. It is clear that the prevention of severe fungal infection by the use of effective infection control measure should be the priority of the teams involved in managing at-risk patients. The evidence from clinical and molecular epidemiological studies is reviewed and current thinking on sources and routes of transmission of the organism are discussed. Our increasing understanding of these has led to the development of a variety of environmental and general strategies for the prevention of IA. It is anticipated that these, coupled with the use of prophylactic antifungal agents active against Aspergillus spp., will have a significant impact upon the morbidity and mortality associated with this infection.

Invasive aspergillosis. Clinical features of 35 proven cases at a single institution

Thirty-five patients with clinical features and histologically or microbiologically proven infection met predetermined stringent criteria for invasive aspergillosis over a 5-year period at our institution. Underlying conditions included hematologic malignancy, solid tumor, bone marrow and solid organ transplantation, and immunosuppressive therapy. The majority of patients (94%) presented with respiratory symptoms and abnormal pulmonary chest radiography; only 40% had neutropenia at time of infection. Invasive aspergillosis was suspected in only 21 cases (60%). Concomitant infections were present in 83% of patients. Half of patients had pathogenic or potentially pathogenic microorganisms other than Aspergillus spp. isolated from pulmonary specimens at time of aspergillosis. Aspergillus spp. were recovered from sputum in 75% of patients and from bronchoalveolar lavage in only 52%. Invasive aspergillosis is an unexpectedly unrecognized disease with poor outcome; overall mortality was 94% in our series. The lack of sensitivity of diagnostic procedures, together with the high frequency of concomitant infections, delays the time of diagnosis. Early diagnostic tests are needed, and presumptive antifungal therapy among high-risk patients is mandatory.

Sequestration of the alveolar bone by invasive aspergillosis in acute myeloid leukemia

Compared to non-invasive aspergillosis, invasive aspergillosis in the region of the mouth, jaw and face has rarely been reported. It occurs particularly often in the presence of haematological oncological illness. The case of a patient suffering from acute myeloid leukemia is described; he contracted invasive aspergillosis of the lungs and the alveolar processes in the course of chemotherapeutic treatment. All the alveolar processes in the region of the premolars and molars were demarcated and had to be removed by sequestrectomy. The therapy of invasive aspergillosis should be carried out within the framework of intensive interdisciplinary treatment. In addition to systemic and local antimycotic therapy, the debridement of necrotic hard and soft tissue was necessary.

Antifungal prophylaxis during neutropenia and immunodeficiency

Fungal infections represent a major source of morbidity and mortality in patients with almost all types of immunodeficiencies. These infections may be nosocomial (aspergillosis) or community acquired (cryptococcosis), or both (candidiasis). Endemic mycoses such as histoplasmosis, coccidioidomycosis, and penicilliosis may infect many immunocompromised hosts in some geographic areas and thereby create major public health problems. With the wide availability of oral azoles, antifungal prophylactic strategies have been extensively developed. However, only a few well-designed studies involving strict criteria have been performed, mostly in patients with hematological malignancies or AIDS. In these situations, the best dose and duration of administration of the antifungal drug often remain to be determined. In high-risk neutropenic or bone marrow transplant patients, fluconazole is effective for the prevention of superficial and/or systemic candidal infections but is not always able to prolong overall survival and potentially selects less susceptible or resistant Candida spp. Primary prophylaxis against aspergillosis remains investigative. At present, no standard general recommendation for primary antifungal prophylaxis can be proposed for AIDS patients or transplant recipients. However, for persistently immunocompromised patients who previously experienced a noncandidal systemic fungal infection, prolonged suppressive antifungal therapy is often indicated to prevent a relapse. Better strategies for controlling immune deficiencies should also help to avoid some potentially life-threatening deep mycoses. When prescribing antifungal prophylaxis, physicians should be aware of the potential emergence of resistant strains, drug-drug interactions, and the cost. Well-designed, randomized, multicenter clinical trials in high-risk immunocompromised hosts are urgently needed to better define how to prevent severe invasive mycoses.

Guidelines for the investigation of invasive fungal infections in haematological malignancy and solid organ transplantation. British Society for Medical Mycology

Invasive fungal infections are increasing in incidence and now affect as many as 50% of neutropenic/bone marrow transplant patients and 5 to 20% of solid organ transplant recipients. Unfortunately, many of the diagnostic tests available have a low sensitivity. The guidelines presented here have been produced by a working party of the British Society for Medical Mycology in an attempt to optimise the use of these tests. The yield of fungi from blood cultures can be increased by ensuring that at least 20 ml of blood are taken for aerobic culture, by using more than one method of blood culture, and by employing terminal subculture if continuous monitoring systems are used with a five-day incubation protocol. Skin lesions in febrile neutropenic patients should be biopsied and cultured for fungi. The detection of galactomannan in blood or urine is of value in diagnosing invasive aspergillosis only if tests are performed at least twice weekly in high-risk patients. Antigen detection tests for invasive candidiasis are less valuable. Computed tomography scanning is particularly valuable in diagnosing invasive pulmonary fungal infection when the chest radiograph is negative or shows only minimal changes. Bronchoalveolar lavage is most useful in patients with diffuse changes on computed tomography scan. The major advances in the diagnosis of invasive fungal infection in patients with haematological malignancy or solid organ transplantation have been in the use of imaging techniques, rather than in the development of new mycological methods in the routine laboratory.

Fungal infections in patients with acquired immunodeficiency syndrome

The incidence and severity of fungal infections appear to increase with progression of HIV disease. Because of the significant morbidity and mortality associated with the mycoses discussed, knowledge of the clinical syndromes, early diagnosis, and prompt institution of therapy are crucial for a favorable outcome. For disseminated or invasive fungal infections, suppressive therapy must be continued to prevent relapse.

Fungal infections

Fungal infections have increased in frequency in the last decades because of the growing number of immunocompromised patients who survive longer periods of time than in the past, the widespread use of immunosuppressive drugs, a large aging population with increased numbers of malignancies, and the spread of AIDS. Although fungi are present everywhere, some mycoses predominate in the tropics, not only in view of warm temperature and humid climate, which favor their growth, but also because of inadequate hygienic and working conditions brought about by poverty. Mycotic diseases in the brain are usually secondary to infections elsewhere in the body, usually the lungs, less often from other extracranial sites, and in the vast majority of the cases spread via blood circulation. Only occasionally they result from direct extensions from infections of the sinuses or bone, and less frequently from prosthetic heart valves. Candida may be endogenous in origin, inhabiting the digestive tract. Most fungi cause basal meningitis or intraparenchymal abscesses. Direct extension from the cribriform plate cause necro-hemorrhagic lesions in the base of the frontal lobe. Although fungi are common in our environment, few are pathogenic. In this paper mycotic infections are divided into opportunistic and pathogenic; although most of the latter have also been described in immunosuppressed patients, some of those caused by opportunistic organisms, have also occurred in the absence of predisposing factors.