Clinical significance of lower respiratory tract Aspergillus culture in elderly hospitalized patients

Clinical performance of metagenomic next-generation sequencing for diagnosis of pulmonary Aspergillus infection and colonization

Background

Investigations assessing the value of metagenomic next-generation sequencing (mNGS) for distinguish Aspergillus infection from colonization are currently insufficient.

Methods

The performance of mNGS in distinguishing Aspergillus infection from colonization, along with the differences in patients' characteristics, antibiotic adjustment, and lung microbiota, were analyzed.

Results

The abundance of Aspergillus significantly differed between patients with Aspergillus infection (n=36) and colonization (n=32) (P < 0.0001). Receiver operating characteristic (ROC) curve result for bronchoalveolar lavage fluid (BALF) mNGS indicated an area under the curve of 0.894 (95%CI: 0.811-0.976), with an optimal threshold value of 23 for discriminating between Aspergillus infection and colonization. The infection group exhibited a higher proportion of antibiotic adjustments in comparison to the colonization group (50% vs. 12.5%, P = 0.001), with antibiotic escalation being more dominant. Age, length of hospital stay, hemoglobin, cough and chest distress were significantly positively correlated with Aspergillus infection. The abundance of A. fumigatus and Epstein-Barr virus (EBV) significantly increased in the infection group, whereas the colonization group exhibited higher abundance of A. niger.

Conclusion

BALF mNGS is a valuable tool for differentiating between colonization and infection of Aspergillus. Variations in patients' age, length of hospital stay, hemoglobin, cough and chest distress are observable between patients with Aspergillus infection and colonization.

Chronic pulmonary aspergillosis: comprehensive insights into epidemiology, treatment, and unresolved challenges

Chronic pulmonary aspergillosis (CPA) is a challenging respiratory infection caused by the environmental fungus Aspergillus. CPA has a poor prognosis, with reported 1-year mortality rates ranging from 7% to 32% and 5-year mortality rates ranging from 38% to 52%. A comprehensive understanding of the pathogen, pathophysiology, risk factors, diagnosis, surgery, hemoptysis treatment, pharmacological therapy, and prognosis is essential to manage CPA effectively. In particular, Aspergillus drug resistance and cryptic species pose significant challenges. CPA lacks tissue invasion and has specific features such as aspergilloma. The most critical risk factor for the development of CPA is pulmonary cavitation. Diagnostic approaches vary by CPA subtype, with computed tomography (CT) imaging and Aspergillus IgG antibodies being key. Treatment strategies include surgery, hemoptysis management, and antifungal therapy. Surgery is the curative option. However, reported postoperative mortality rates range from 0% to 5% and complications range from 11% to 63%. Simple aspergilloma generally has a low postoperative mortality rate, making surgery the first choice. Hemoptysis, observed in 50% of CPA patients, is a significant symptom and can be life-threatening. Bronchial artery embolization achieves hemostasis in 64% to 100% of cases, but 50% experience recurrent hemoptysis. The efficacy of antifungal therapy for CPA varies, with itraconazole reported to be 43-76%, voriconazole 32-80%, posaconazole 44-61%, isavuconazole 82.7%, echinocandins 42-77%, and liposomal amphotericin B 52-73%. Combinatorial treatments such as bronchoscopic triazole administration, inhalation, or direct injection of amphotericin B at the site of infection also show efficacy. A treatment duration of more than 6 months is recommended, with better efficacy reported for periods of more than 1 year. In anticipation of improvements in CPA management, ongoing advances in basic and clinical research are expected to contribute to the future of CPA management.

Role of COPD in a case of fatal Aspergillus niger tracheobronchitis

A man with chronic obstructive pulmonary disease (COPD) in his mid-60s was admitted for respiratory failure due to multifocal, necrotising pneumonia. Despite initial improvement with antimicrobial therapy, the patient developed hemoptysis and progressive infiltrates. Subsequent fungal cultures from his bronchoalveolar lavage were positive for Aspergillus niger and treatment with voriconazole was added for suspected invasive pulmonary aspergillosis (IPA). A repeat bronchoscopy revealed cobblestone lesions with mucosal friability throughout the lower trachea and bilateral mainstem bronchi. Endobronchial biopsy showed septated hyphae confirming the diagnosis of IPA. Despite appropriate therapy, the patient declined further and passed away on hospital day 11. Invasive infections with A. niger are infrequent, with a paucity of data on clinical course and outcomes. Our case adds to the current body of literature regarding the potential virulence of this species in patients with COPD.

Development and clinical implications of a novel CRISPR-based diagnostic test for pulmonary Aspergillus fumigatus infection

BACKGROUND

Rapid and reliable diagnostic methods for Aspergillus fumigatus infection are urgently needed. Clustered regularly interspaced short palindromic repeat (CRISPR)-associated protein 13a (Cas13a) has high sensitivity and specificity in the diagnosis of viral infection. However, its potential use in detecting A. fumigatus remains unexplored. A highly sensitive and specific method using the CRISPR/Cas13a system was developed for the reliable and rapid detection of A. fumigatus.

METHODS

The conserved internal transcribed spacer (ITS) region of A. fumigatus was used to design CRISPR-derived RNA (crRNA) and the corresponding recombinase polymerase amplification (RPA) primer sequence with the T7 promoter for the CRISPR assay. Twenty-five clinical isolates and 43 bronchoalveolar lavage fluid (BALF) remaining from routine examinations of patients with confirmed pulmonary aspergillosis were collected to further validate the CRISPR assay.

RESULTS

No amplification signal was observed when genomic DNA from closely clinically related Aspergillus species, such as Aspergillus flavus, Aspergillus niger, and Aspergillus terreus, as well as Monascus purpureus Went and Escherichia coli, was tested by this assay, and the detection limit for A. fumigatus was 3 copies in a single reaction system. Validation experiments using the 25 clinical isolates demonstrated 91.7% specificity for the A. fumigatus section, and the sensitivity was 100% when first-generation sequencing was used as the standard. There was no significant difference between the PCR and CRISPR methods (P = 1.0), and the diagnosis results of the two methods were consistent (Kappa = 0.459, P = 0.003).

CONCLUSION

The study offers a new validated CRISPR/Cas13a technique for A. fumigatus detection, providing a simple, rapid and affordable test that is ready for application in the diagnosis of A. fumigatus infection.

Recent Advances in Fungal Infections: From Lung Ecology to Therapeutic Strategies With a Focus on Aspergillus spp

Fungal infections are estimated to be the main cause of death for more than 1.5 million people worldwide annually. However, fungal pathogenicity has been largely neglected. This is notably the case for pulmonary fungal infections, which are difficult to diagnose and to treat. We are currently facing a global emergence of antifungal resistance, which decreases the chances of survival for affected patients. New therapeutic approaches are therefore needed to face these life-threatening fungal infections. In this review, we will provide a general overview on respiratory fungal infections, with a focus on fungi of the genus Aspergillus. Next, the immunological and microbiological mechanisms of fungal pathogenesis will be discussed. The role of the respiratory mycobiota and its interactions with the bacterial microbiota on lung fungal infections will be presented from an ecological perspective. Finally, we will focus on existing and future innovative approaches for the treatment of respiratory fungal infections.

Efficacy of Gold Nanoparticles against Drug-Resistant Nosocomial Fungal Pathogens and Their Extracellular Enzymes: Resistance Profiling towards Established Antifungal Agents

Drug resistance of filamentous fungi to the commonly used antifungal agents is a major concern in medicine. Therefore, an effective approach to treat several opportunistic fungal infections is the need of the hour. Mentha piperita is used in home remedies to treat different disorders. Isolates of fungi were taken from hospitals in Riyadh, Saudi Arabia, and identified using molecular tools. Amphotericin B, Voriconazole, and Micafungin were applied to screen the resistance of these isolates using both disc and broth microdilution techniques. An aqueous extract of Mentha piperita was utilized to synthesize AuNPs and the nanoparticles were characterized using UV-Vis, FTIR, TEM, EDAX, and XRD. The AuNPs were tested for antifungal activity against the nosocomial fungal pathogens and the activity of extracellular enzymes of such pathogens were analyzed after treatment with AuNPs. We conclude that AuNPs synthesized using Mentha piperita do not possess especially effective antifungal properties against multi-drug resistant Aspergillus species. Five out of eighteen isolates were inhibited by AuNPs. When inhibition was observed, significant alterations in the activity profile of extracellular enzymes of the nosocomial fungi were observed.

Invasive fungal disease and the immunocompromised host including allogeneic hematopoietic cell transplant recipients: Improved understanding and new strategic approach with sargramostim

In hosts with damaged or impaired immune systems such as those undergoing hematopoietic cell transplant (HCT) or intensive chemotherapy, breakthrough fungal infections can be fatal. Risk factors for breakthrough infections include severe neutropenia, use of corticosteroids, extended use of broad-spectrum antibiotics, and intensive care unit admission. An individual's cumulative state of immunosuppression directly contributes to the likelihood of experiencing increased infection risk. Incidence of invasive fungal infection (IFI) after HCT may be up to 5-8%. Early intervention may improve IFI outcomes, although many infections are resistant to standard therapies (voriconazole, caspofungin, micafungin, amphotericin B, posaconazole or itraconazole, as single agents or in combination). We review herein several contributing factors that may contribute to the net state of immunosuppression in recipients of HCT. We also review a new approach for IFI utilizing adjunctive therapy with sargramostim, a yeast-derived recombinant human granulocyte-macrophage colony-stimulating factor (rhu GM-CSF).

Relationship between spirometry results and colonisation of Aspergillus species in allergic asthma

INTRODUCTION AND OBJECTIVES

Exposure to fungi in patients with asthma leads to the release of various fungal antigens, which can increase the severity of asthma. Regarding this, the present study was conducted to evaluate the relationship between the colonisation of Aspergillus species and spirometry results in allergic asthma.

MATERIALS AND METHODS

Two hundred sixteen patients with mild to severe asthma and 30 healthy controls were included. All participants underwent pulmonary function tests. Furthermore, sputum samples were collected from each subject. Each sputum sample was subjected to direct microscopic examination and fungal culture. All cultured Aspergillus colonies were identified at species level by molecular methods. Finally, all available data from sputum culture and spirometry test were analysed.

RESULTS

Out of 216 sputum samples, 145 (67.1%) were positive for fungal growth. Furthermore, out of 264 grown fungal colonies, 137 (51.9%) were Aspergillus species. Among the Aspergillus isolates, A. flavus (29.2%) was the most prevalent species, followed by A. fumigatus (27.7%). The mean forced expiratory volume in one second (FEV1) in the mild, moderate and severe asthmatic patients with a positive sputum culture for fungi were obtained as 90.0 ± 11.1, 71.1 ± 15.9 and 54.9 ± 16.4, respectively. In general, Aspergillus species colonisation had no statistically significant effect on spirometry results of study patients.

CONCLUSION

Our results showed that there is no difference in the FEV1 and forced vital capacity between Aspergillus positive and negative patients in any asthma severity group.

Advances in the diagnosis of fungal pneumonias

INTRODUCTION

Fungal infections are increasingly encountered in clinical practice due to more favorable environmental conditions and increasing prevalence of immunocompromised individuals. The diagnostic approach for many fungal pathogens continues to evolve. Herein, we outline available diagnostic tests for the most common fungal infections with a focus on recent advances and future directions.

AREAS COVERED

We discuss the diagnostic testing methods for angioinvasive molds (Aspergillus spp. and Mucor spp.), invasive yeast (Candida spp. and Cryptococcus ssp.), Pneumocystis, and endemic fungi (Blastomyces sp., Coccidioides ssp., and Histoplasma sp.). The PubMed-NCBI database was searched within the past 5 years to identify the most recent available literature with dates extended in cases where literature was sparse. Diagnostic guidelines were utilized when available with references reviewed.

EXPERT OPINION

Historically, culture and/or direct visualization of fungal organisms were required for diagnosis of infection. Significant limitations included ability to collect specimens and delayed diagnosis associated with waiting for culture results. Antigen and antibody testing have made great strides in allowing quicker diagnosis of fungal infections but can be limited by low sensitivity/specificity, cross-reactivity with other fungi, and test availability. Molecular methods have a rich history in some fungal diseases, while others continue to be developed.

Molecular Detection of Aspergillus in Sputum of Patients with Lower Respiratory Tract Infections

BACKGROUND

Raised incidences of respiratory tract infections due to fungal agents in immunocompetent individuals are a cause of concern due to the unavailability of rapid diagnostic methods.

MATERIALS AND METHODS

Sputum and serum samples were collected from patients having lower respiratory tract infections (LRTIs), serum samples were screened for the presence of anti Aspergillus antibodies and sputum samples were homogenized and processed for identification of Aspergillus by conventional methods and further subjected to polymerase chain reaction (PCR) using genus-specific ITS 4-5 primers.

RESULTS

PCR identified Aspergillus in 28% sputum samples, which was high as compared to conventional methods.

CONCLUSION

Simple conventional PCR technique proves to be useful screening in for early identification of Aspergillus colonization in patients with LRTI, which can prevent irreversible damage in their lungs by fungal invasion.

The spectrum of pulmonary aspergillosis

Notable progress has been made in the past years in the classification, diagnosis and treatment of pulmonary aspergillosis. New criteria were proposed by the Working Group of the International Society for Human and Animal Mycology (ISHAM) for the diagnosis of allergic bronchopulmonary aspergillosis (ABPA). The latest classification of chronic pulmonary aspergillosis (CPA) suggested by the European Society for Clinical Microbiology and Infectious Diseases (ESCMID) has become widely accepted among clinicians. Subacute invasive pulmonary aspergillosis is now considered a type of CPA, yet it is still diagnosed and treated similarly to invasive pulmonary aspergillosis (IPA). Isavuconazole, an extended-spectrum triazole, has recently been approved by the Food and Drug Administration (FDA) and the European Medicines Agency (EMA) for the treatment of IPA. The most recent Infectious Diseases Society of America (IDSA) guidelines strongly recommend reducing mold exposure to patients at high risk for pulmonary aspergillosis. The excessive relapse rate following discontinuation of therapy remains a common reality to all forms of this semi-continuous spectrum of diseases. This highlights the need to continuously reassess patients and individualize therapy accordingly. Thus far, the duration of therapy and the frequency of follow-up have to be well characterized.

Diagnosis, classification, and therapeutic interventions for sinopulmonary Aspergillosis

INTRODUCTION

Sinopulmonary aspergillosis represents a diverse collection of allergic, invasive, and chronic sinus and respiratory conditions. These diseases can affect patients with and without immune impairment and in some cases may be life-threatening. Areas covered: We review the diagnosis, classification, and therapeutic options available to treat sinopulmonary aspergillosis and look ahead to emerging diagnostic and therapeutic options that may soon play an important role in clinical practice. Expert commentary: Histopathology and tissue culture remain the gold standard for the diagnosis of invasive sinopulmonary aspergillosis, but several new molecular detection methods have recently emerged, including various PCR-based platforms, MALDI-TOF, and lateral flow assays. We examine these methodologies as well as the barriers associated with the standardization, validation, and implementation. We also explore the pipeline of antifungal agents in development to treat sinopulmonary aspergillosis.

Invasive pulmonary aspergillosis - case report and review of literature

Invasive pulmonary aspergillosis (IPA) is a severe fungal infection with a high mortality rate. The incidence of IPA is on the rise due to an increase in the number of patients undergoing transplants and receiving chemotherapy and immunosuppressive therapy. Diagnosis is challenging due to the non-specific nature of symptoms. Voriconazole is the mainstay of therapy. We present a case of an elderly woman presenting with acute bronchitis and asthma exacerbation, who succumbed to overwhelming IPA. It is uncommon for IPA to develop in patients on short-term steroid therapy for asthma exacerbation. The possibility of aspergillosis in immunocompetent patients should be considered in those on systemic steroids and deteriorating pulmonary functions.

Immunoproteome of Aspergillus fumigatus using sera of patients with invasive aspergillosis

Invasive aspergillosis is a life-threatening lung or systemic infection caused by the opportunistic mold Aspergillus fumigatus. The disease affects mainly immunocompromised hosts, and patients with hematological malignances or who have been submitted to stem cell transplantation are at high risk. Despite the current use of Platelia™ Aspergillus as a diagnostic test, the early diagnosis of invasive aspergillosis remains a major challenge in improving the prognosis of the disease. In this study, we used an immunoproteomic approach to identify proteins that could be putative candidates for the early diagnosis of invasive aspergillosis. Antigenic proteins expressed in the first steps of A. fumigatus germination occurring in a human host were revealed using 2-D Western immunoblots with the serum of patients who had previously been classified as probable and proven for invasive aspergillosis. Forty antigenic proteins were identified using mass spectrometry (MS/MS). A BLAST analysis revealed that two of these proteins showed low homology with proteins of either the human host or etiological agents of other invasive fungal infections. To our knowledge, this is the first report describing specific antigenic proteins of A. fumigatus germlings that are recognized by sera of patients with confirmed invasive aspergillosis who were from two separate hospital units.

Repeated Aspergillus isolation in respiratory samples from non-immunocompromised patients not selected based on clinical diagnoses: colonisation or infection?

Background

Isolation of Aspergillus from lower respiratory samples is associated with colonisation in high percentage of cases, making it of unclear significance. This study explored factors associated with diagnosis (infection vs. colonisation), treatment (administration or not of antifungals) and prognosis (mortality) in non-transplant/non-neutropenic patients showing repeated isolation of Aspergillus from lower respiratory samples.

Methods

Records of adult patients (29 Spanish hospitals) presenting ≥2 respiratory cultures yielding Aspergillus were retrospectively reviewed and categorised as proven (histopathological confirmation) or probable aspergillosis (new respiratory signs/symptoms with suggestive chest imaging) or colonisation (symptoms not attributable to Aspergillus without dyspnoea exacerbation, bronchospasm or new infiltrates). Logistic regression models (step–wise) were performed using Aspergillosis (probable + proven), antifungal treatment and mortality as dependent variables. Significant (p < 0.001) models showing the highest R² were considered.

Results

A total of 245 patients were identified, 139 (56.7%) with Aspergillosis. Aspergillosis was associated (R² = 0.291) with ICU admission (OR = 2.82), congestive heart failure (OR = 2.39) and steroids pre-admission (OR = 2.19) as well as with cavitations in X-ray/CT scan (OR = 10.68), radiological worsening (OR = 5.22) and COPD exacerbations/need for O₂ interaction (OR = 3.52). Antifungals were administered to 79.1% patients with Aspergillosis (100% proven, 76.8% probable) and 29.2% colonised, with 69.5% patients receiving voriconazole alone or in combination. In colonised patients, administration of antifungals was associated with ICU admission at hospitalisation (OR = 12.38). In Aspergillosis patients its administration was positively associated (R² = 0.312) with bronchospasm (OR = 9.21) and days in ICU (OR = 1.82) and negatively with Gold III + IV (OR = 0.26), stroke (OR = 0.024) and quinolone treatment (OR = 0.29). Mortality was 78.6% in proven, 41.6% in probable and 12.3% in colonised patients, and was positively associated in Aspergillosis patients (R² = 0.290) with radiological worsening (OR = 3.04), APACHE-II (OR = 1.09) and number of antibiotics for treatment (OR = 1.51) and negatively with species other than A. fumigatus (OR = 0.14) and aspergillar tracheobronchitis (OR = 0.27).

Conclusions

Administration of antifungals was not always closely linked to the diagnostic categorisation (colonisation vs. Aspergillosis), being negatively associated with severe COPD (GOLD III + IV) and concomitant treatment with quinolones in patients with Aspergillosis, probably due to the similarity of signs/symptoms between this entity and pulmonary bacterial infections.

Clinical features of invasive pulmonary aspergillosis vs. colonization in COPD patients distributed by gold stage

OBJECTIVE

To explore clinical features of invasive pulmonary aspergillosis (IPA) vs. colonization among hospitalized COPD patients.

METHODS

Records of COPD patients with two respiratory cultures yielding Aspergillus were retrospectively reviewed. Cases categorized as proven/probable IPA or colonization was analyzed.

RESULTS

118 patients were identified: 70 (59.3%) colonized, 48 (40.7%) with IPA (42 probable, 6 proven). Higher percentage of IPA patients (vs. colonized) presented GOLD III + IV (77.1% vs. 57.1%, p = 0.025). IPA patients presented higher Charlson index (3.5 ± 2.5 vs. 2.6 ± 2.2, p = 0.027), higher rate of ICU admission (27.1% vs. 4.3%, p = 0.001) and worse prognosis (McCabe rapidly fatal category: 31.3% vs. 7.1%, p = 0.001). GOLD-I IPA patients presented risk factors other than COPD. Before hospitalization, 66.7% IPA and 28.6% colonized patients were taking steroids (p < 0.001). Antifungals were administered to 83.3% IPA and 21.4% colonized patients (p < 0.001). Mortality was higher among IPA vs. colonized patients, both in global (58.3% vs. 10.0%, p < 0.001), GOLD-I (75.0% vs. 10.0%, p = 0.041), GOLD-II (42.9% vs. 5.0%, p = 0.042) and GOLD-III patients (54.2% vs. 0.0%, p < 0.001), but not in GOLD-IV patients (69.2% vs. 31.3%, p = 0.066).

CONCLUSIONS

IPA should be suspected not only in GOLD-III and GOLD-IV COPD patients, with higher mortality in IPA vs. colonized patients for GOLD-II and -III COPD patients.

A prospective survey of Aspergillus spp. in respiratory tract samples: prevalence, clinical impact and antifungal susceptibility

A three-month laboratory-based prospective survey was conducted at four major university hospitals covering one-third of the Danish population in order to determine the prevalence, significance, and susceptibility pattern of aspergilli in airway samples. Samples received in January-March 2007 for routine microbiologic investigation were examined for Aspergillus following routine procedures and with extended incubation (5 days). Identification was done by morphologic criteria and susceptibility testing using EUCAST method for azoles and amphotericin B E-test. Invasive aspergillosis (IA) was evaluated using modified EORTC/MSG criteria. A total of 11,368 airway samples were received. Growth of Aspergillus spp. was found in 129 and 151 patients using routine and extended incubation, respectively. Three patients had proven IA (2%), 11 probable (7%), four had allergic bronchopulmonary aspergillosis (ABPA) (3%), but the majority was colonised (88%). Underlying conditions were cystic fibrosis in 82 patients (55%), chronic obstructive pulmonary disease in 19 (13%) and haematological disorder in 11 (7%). Twenty-six patients (18%) were at intensive care unit and 69 (47%) received steroid treatment. Azole MICs were elevated for five isolates as follows (itraconazole, posaconazole, voriconazole MICs [mg/L]): two A. fumigatus isolates (>4; >4; 2 and >4; 0.125; 1), one A. lentulus isolate (2; 2; 0.5) and two A. terreus isolates (2; 2; 2 and 2; 0.125; 1). For four isolates the amphotericin B MIC was >1 μg/ml (3/112 A. fumigatus, 1/2 A. terreus). In conclusion, Aspergillus appears to be an important pathogen in Denmark. Elevated itraconazole MICs were detected in 4% of the isolates including a multi-azole resistant isolate.

Diagnostic significance of Aspergillus species isolated from respiratory samples in an adult pneumology ward

Although the diagnostic significance of isolating Aspergillus spp. from respiratory cultures has been studied in immunocompromised hosts with invasive pulmonary aspergillosis (IPA), little is known of such infections in immunocompetent patients with other forms of aspergillosis. In this study of adult pneumology ward patients, we examined the association between Aspergillus spp. and disease prevalence. Laboratory records from April 1998 to March 2009 were reviewed to identify patients with Aspergillus spp. in respiratory samples. Correlations between the isolated species and clinical characteristics of patients were evaluated. During the study period, 165 Aspergillus spp. isolates were detected in the respiratory cultures of 139 patients. Of these patients, 62 (45%) were colonized with Aspergillus spp. and displayed no clinical symptoms of aspergillosis, while 77 (55%) had a form of pulmonary aspergillosis, characterized as either chronic necrotizing pulmonary aspergillosis (CNPA) (48%), aspergilloma (29%), IPA (13%), or allergic bronchopulmonary aspergillosis (ABPA) (10%). The dominant species were Aspergillus fumigatus (41%), A. niger (32%), and A. versicolor (12%). A. fumigatus was most commonly isolated in patients with IPA, aspergilloma, and CNPA, whereas A. niger was the dominant species in colonized patients and those with ABPA. Isolation of an Aspergillus spp. from respiratory samples does not confirm it as the etiologic pathogen because airway colonization by Aspergillus spp. is a common feature in several chronic lung diseases. Repeated isolation of the identical Aspergillus species and detection of anti-Aspergillus antibodies and/or Aspergillus antigens in sera are needed to determine the isolate represents the etiologic agent of disease.

[Invasive pulmonary aspergillosis in a hematooncological patient in the intensive care units. A review of the literature]

Invasive aspergillosis is a common condition in patients with hematologic malignancies. Symptoms are extremely non-specific, and therefore it is necessary to be familiar with the diagnostic tests for early diagnosis. This review has attempted to clarify the current evidence regarding the following areas: clinical presentation, methods of study and treatment of this condition in hemato-oncological critical patients.

Indoor air studies of fungi contamination at the Department of Pulmonology and Internal Medicine in Kavala Hospital in Greece

PURPOSE

The aim of the study was to assess the presence of airborne fungi and the fungal flora of the walls in the Departments of Pulmonary and Internal Medicine in Kavala Hospital (Greece).

MATERIAL AND METHODS

The study was carried out at the Department of Pulmonology and Internal medicine in Kavala Hospital. Materials for the tests were: the air samples (in front of the building and the selected rooms) and swabs from the walls. The air pollution was determined using SAS SUPER 100 (Pbi International). The microbial flora from walls was assessed using the Count-Tact applicator and the plate Count-Tact (BioMerieux). Humidity and temperature were evaluated by a thermo-hygrometer.

RESULTS

The following fungal pathogens isolated from air were Aspergillus, Candida albicans, Candida spp., and Penicillium species in the Department of Pulmonary. Similar pathogens in the air of Department and Internal Medicine were found. Mean number of fungi colonies isolated from air in the Department of Pulmonology was significantly (p<0.001) higher compared to the Department of Internal Medicine. No significant correlations between CFU of fungi in air and temperature in both Departments were found.

CONCLUSIONS

The main fungal pathogens isolated from the air samples were Aspergillus and Candida albicans in the Departments of Pulmonary and Internal Medicine in Kavala Hospital. Fungal occurrence in the air of rooms and walls varied between the both departments of the same hospital.

Invasive pulmonary aspergillosis in patients with COPD: a report of five cases and systematic review of the literature

BACKGROUND

There are increasing reports describing invasive pulmonary aspergillosis (IPA) in patients with chronic obstructive pulmonary disease (COPD) without the classic risk factors for this severe infection. The available literature on this association is based on case reports or small case series. The aim of this review is to systematically review these cases and describe the clinical features, diagnostic studies and outcome.

METHODS

We identified all the cases of IPA and COPD reported in the literature and had enough clinical information. We also included five cases of IPA in patients with COPD identified by the authors. These cases were systematically reviewed for clinical features, diagnostic studies and outcome.

RESULTS

There were 60 cases of IPA in patients with COPD identified from the literature. The total number of cases reviewed was 65. The mean age was 65.1 years, the mean FEV1 was 39% of predicted (n = 17, range 19-56%). Forty-nine patients were documented to be on systemic corticosteroids. The mean dose was 24 mg/day (range 15-65 mg/day). Five patients were only on inhaled corticosteroids and in 11 patients there was no documentation of corticosteroid therapy. The clinical and radiological findings were nonspecific. Thirteen patients had documented evidence of disseminated IPA. Sputum examination was positive for Aspergillus in 76% and bronchoscopy with bronchoalveolar lavage that was positive in 70%. The diagnosis of IPA was definite in 43 patients and probable in 22 patients. Forty-six patients were treated with anti-fungal therapy. Fifty-nine patients (91%) died with IPA.

CONCLUSION

Invasive pulmonary aspergillosis is an emerging serious infection in patients with COPD. The majority of these patients have advanced COPD and/or on corticosteroid therapy. The clinical and radiological presentation is nonspecific. High index of suspicion is necessary for the timely treatment of these patients.

Management of invasive pulmonary aspergillosis in non-neutropenic critically ill patients

During recent years, a rising incidence of invasive pulmonary aspergillosis (IPA) in non-neutropenic critically ill patients has been reported. Critically ill patients are prone to develop disturbances in immunoregulation during their stay in the ICU, which render them more vulnerable for fungal infections. Risk factors such as chronic obstructive pulmonary disease (COPD), prolonged use of steroids, advanced liver disease, chronic renal replacement therapy, near-drowning and diabetes mellitus have been described. Diagnosis of IPA may be difficult and obtaining histo- or cytopathological demonstration of the fungus in order to meet the gold standard for IPA is not always feasible in these patients. Laboratory markers used as a non-invasive diagnostic tool, such as the galactomannan antigen test (GM), 1,3-beta-glucan, and Aspergillus PCR, show varying results. Antifungal therapy might be considered in patients with persistent pulmonary infection who exhibit risk factors together with positive cultures or sequentially positive GM and Aspergillus PCR in serum, in whom voriconazole is the drug of choice. The benefit of combination antifungal therapy lacks sufficient evidence so far, but this treatment might be considered in patients with breakthrough infections or refractory disease.

Isolation of Aspergillus in critically ill patients: a potential marker of poor outcome

OBJECTIVE

Recent reports have suggested a rising incidence of pulmonary aspergillosis in intensive care unit (ICU) patients. The aim of this study was to determine the clinical significance of isolating Aspergillus from respiratory samples of critically ill patients.

DESIGN

Retrospective review of medical records.

SETTING

Tertiary medical center that has a large cancer center.

PATIENTS

All patients admitted to the ICU between January 1998 and August 2004, in whom Aspergillus was isolated from respiratory samples or lung tissue.

INTERVENTION

None.

RESULTS

The charts of 104 patients were reviewed. Aspergillus was isolated for a mean of 6.6 days after ICU admission. Thirty-three percent of patients had hematological malignancy, 10% had absolute neutropenia, 14% had bone marrow transplant, 11% had HIV infection, and 22% had chronic obstructive pulmonary disease. Upon admission to ICU, 79%, 43%, and 19% were on antibiotics, corticosteroids, or immunosuppressive therapy, respectively. Ninety percent of patients required mechanical ventilation. The mean Acute Physiologic and Chronic Health Evaluation II score on ICU admission was 20.6, with predicted mortality of 35.5%. However, the actual ICU mortality rate for the cohort was 50%. Twenty-eight percent of patients were diagnosed with probable or definite invasive pulmonary aspergillosis, and 72% had Aspergillus colonization. On univariate analysis, the significant clinical differences between the 2 groups were the presence of neutropenia (P < .05), immunosuppressants (P < .05), antibiotics (P < .05), or bone marrow transplant (P < .05). The differences in Acute Physiologic and Chronic Health Evaluation II score, the need for mechanical ventilation, ICU length of stay, and ICU mortality were not statistically significant. On multivariate analysis, the following factors were independently associated with invasive diseases, bone marrow transplantation (P < .01), hematological malignancy (P = .02), and broad-spectrum antibiotics (P = .02).

CONCLUSION

Isolation of Aspergillus in critically ill patients is a poor prognostic marker and is associated with high mortality irrespective of invasion or colonization. Those who are neutropenic, on immunosuppressive therapy, on broad-spectrum antibiotics, or had bone marrow transplantation are more likely to have invasive pulmonary aspergillosis.

Critical care considerations of hematopoietic stem cell transplantation

OBJECTIVE

To review the available clinical data on the critical care complications of hematopoietic stem cell transplantation (HSCT).

DATA SOURCE

The MEDLINE database and references from the identified articles related to the critical care in HSCT.

CONCLUSION

HSCT is an important treatment for a variety of malignant and nonmalignant conditions. The procedure is, however, limited by significant complications that may involve every organ of the body. Up to 40% of HSCT recipients are admitted to the intensive care unit as a result of severe complications related to the transplantation. The outcome of those critically ill patients has been traditionally poor. However, recent advances in the transplantation procedure, diagnostic studies, antimicrobial prophylaxis and therapy, and intensive care unit care have improved the outcome of these patients. The increasing number of HSCTs performed annually, the unique complications that develop in these patients, and the improvement in the intensive care unit outcome make knowledge about the critical care aspect of HSCT an essential part of the current practice of critical care medicine.

Detection of Aspergillus fumigatus hyphae in respiratory secretions by membrane filtration, fluorescent labelling and laser scanning

The detection of Aspergillus fumigatus hyphae in bronchoalveolar lavage fluid (BAL) and sputum is diagnostically useful in patients at risk of invasive aspergillosis. We report a dedicated enzymatic-chemical sample pretreatment that allows the application of a previously described solid phase cytometry (SPC) method for detection of A. fumigatus hyphae in sputum and BAL samples. Non-specific detection of fungal hyphae by SPC is based on a 'viability' staining using carboxyfluorescein diacetate. For a specific detection of A. fumigatus hyphae by SPC, viability staining is combined with a pre-incubation at 45 degrees C, immunofluorescent labelling and microscopic recognition of the characteristic hyphal morphology. Low numbers of A. fumigatus hyphae (2-10 hyphae/sample) have now been demonstrated in spiked sputum using the non-specific and specific staining in 2.5 and 8.5 h, respectively.