The value of the chest computed tomography halo sign in the diagnosis of invasive pulmonary aspergillosis. An autopsy-based retrospective study of 48 patients

Radiological CT Patterns and Distribution of Invasive Pulmonary Aspergillus, Non-Aspergillus, Cryptococcus and Pneumocystis Jirovecii Mold Infections - A Multicenter Study

PURPOSE

 Clinical signs and symptoms related to invasive fungal disease are nonspecific and need to be followed up by appropriate diagnostic procedures. The goal of this study was to analyze CT imaging patterns in invasive fungal infections and their correlation with the immune status and clinical outcome.

MATERIALS AND METHODS

 We performed a retrospective multicenter study including 85 consecutive patients with invasive pulmonary fungal infection (2011-2014). Lung patterns on computed tomography (CT) scans were classified according to the Fleischner Society glossary. The patients were grouped according to immune status (neutropenia, steroid therapy, organ transplant recipient, and other cause) and outcome (positive outcome, progressive disease, and death). The Chi square test or Fisher exact test was used. Bonferroni correction was applied.

RESULTS

 The total number of patients with invasive Aspergillus and non-Aspergillus infection (IANA), Pneumocystis jirovecii pneumonia (PCP), and Cryptococcus (CRY) was 60, 22, and 3, respectively. Patients with IANA demonstrated significantly more nodules (93 % vs. 59 %, p = 0.001), significantly fewer ground glass opacities (58 % vs. 96 %, p = 0.005), and significantly fewer positive lymph nodes (5 % vs. 41 %, p < 0.001) than patients with PCP. All patients with PCP and CRY had a favorable outcome. Patients with IANA and an adverse outcome demonstrated significantly more nodules with halo sign than patients with IANA and a favorable outcome (42.5 % vs. 15.9 %, p < 0.0001). Interestingly, patients with IANA and a favorable outcome had a higher prevalence of pulmonary infarction than patients with an adverse outcome (8 % vs. 1 %, p = 0.047). Patients with neutropenia showed significantly more consolidations (66 %) than organ transplant recipients (27 %, p = 0.045).

CONCLUSION

 Patients with IANA showed a higher prevalence of nodules and a lower prevalence of ground glass opacities than patients with PCP. In patients with IANA, nodules with halo sign were associated with an adverse outcome. Patients with neutropenia showed generally more consolidations, but the consolidations were not associated with an adverse outcome.

KEY POINTS

  · Nodules, ground glass opacities, and consolidations are common CT findings in all invasive pulmonary fungal infections.. · There is no pattern that is unique for one specific pathogen, although nodules are more predominant in IANA and Cryptococcus, and ground glass opacities are more predominant in PCP patients.. · Immune status had an impact on CT findings in fungal pneumonia with less consolidation in patients after organ transplantation compared to patients with neutropenia.. · Nodules with a halo sign are associated with a worse outcome..

CITATION FORMAT

· Obmann VC, Bickel F, Hosek N et al. Radiological CT Patterns and Distribution of Invasive Pulmonary Aspergillus, Non-Aspergillus, Cryptococcus and Pneumocystis Jirovecii Mold Infections - A Multicenter Study. Fortschr Röntgenstr 2021; DOI: 10.1055/a-1482-8336.

Guidance on Imaging for Invasive Pulmonary Aspergillosis and Mucormycosis: From the Imaging Working Group for the Revision and Update of the Consensus Definitions of Fungal Disease from the EORTC/MSGERC

BACKGROUND

Clinical imaging in suspected invasive fungal disease (IFD) has a significant role in early detection of disease and helps direct further testing and treatment. Revised definitions of IFD from the EORTC/MSGERC were recently published and provide clarity on the role of imaging for the definition of IFD. Here, we provide evidence to support these revised diagnostic guidelines.

METHODS

We reviewed data on imaging modalities and techniques used to characterize IFDs.

RESULTS

Volumetric high-resolution computed tomography (CT) is the method of choice for lung imaging. Although no CT radiologic pattern is pathognomonic of IFD, the halo sign, in the appropriate clinical setting, is highly suggestive of invasive pulmonary aspergillosis (IPA) and associated with specific stages of the disease. The ACS is not specific for IFD and occurs in the later stages of infection. By contrast, the reversed halo sign and the hypodense sign are typical of pulmonary mucormycosis but occur less frequently. In noncancer populations, both invasive pulmonary aspergillosis and mucormycosis are associated with "atypical" nonnodular presentations, including consolidation and ground-glass opacities.

CONCLUSIONS

A uniform definition of IFD could improve the quality of clinical studies and aid in differentiating IFD from other pathology in clinical practice. Radiologic assessment of the lung is an important component of the diagnostic work-up and management of IFD. Periodic review of imaging studies that characterize findings in patients with IFD will inform future diagnostic guidelines.

CT Halo sign: A systematic review

PURPOSE

The CT Halo sign or Halo sign (HS) refers to ground-glass opacity surrounding a nodule or mass in the lung parenchyma. We conducted a systematic review to find the etiological associations of HS. We also evaluated the diagnostic performances of HS for invasive fungal infections (IFI) in immunosuppressed patients.

METHOD

The systematic review was conducted as per PRISMA guidelines. We searched the PubMed and EMBASE database till June 2018 without any restrictions. Only case reports, case series and original articles published in English language were included. A database created from the electronic searches was compiled and subsequent analysis was done. [PROSPERO registration: CRD42018094739] RESULTS: 168 studies were eligible, which included 51 case reports, 15 prospective studies, 102 retrospective studies. A total of 1977 patients (out of 6371) with HS were identified with age range between <1year-94years. The most common diagnosis in the immunosuppressed, mixed, immunocompetent and not specified groups were IFI (86.9 %, n = 1194), Cryptococcosis (51.6 %, n = 124), Cryptococcosis (40 %, n = 20) and lung neoplasms (81.8 %, n = 36) respectively. 14 studies (11 retrospective, 3 prospective) were included in quantitative analysis. The pooled sensitivity(sn), specificity(sp) and odd's ratio (OR) of HS for diagnosing IFI were 50.4 %, 91 % and 6.61 respectively. Also, HS could not reliably differentiate IPA from mucormycosis in the pooled analysis.

CONCLUSIONS

HS can be seen in a large number of diverse conditions both in immunosuppressed and immunocompetent population. In immunosuppressed patients HS is specific for IFI but cannot rule it out. Additionally, it cannot reliably distinguish between IPA and mucormycosis.

Diagnosis of invasive fungal diseases in haematology and oncology: 2018 update of the recommendations of the infectious diseases working party of the German society for hematology and medical oncology (AGIHO)

Invasive fungal diseases (IFD) are a primary cause of morbidity and mortality in patients with haematological malignancies. These infections are mostly life-threatening and an early diagnosis and initiation of appropriate antifungal therapy are essential for the clinical outcome. Most commonly, Aspergillus and Candida species are involved. However, other Non-Aspergillus moulds are increasingly identified in case of documented IFD. For definite diagnosis of IFD, a combination of diagnostic tools have to be applied, including conventional mycological culture and non-conventional microbiological tests such as antibody/antigen and molecular tests, as well as histopathology and radiology. Although varying widely in cancer patients, the risk of invasive fungal infection is highest in those with allogeneic stem cell transplantation and those with acute leukaemia and markedly lower in patients with solid cancer. Since the last edition of Diagnosis of Invasive Fungal Diseases recommendations of the German Society for Hematology and Oncology in 2012, integrated care pathways have been proposed for the management and therapy of IFDs with either a diagnostic driven strategy as opposed to a clinical or empirical driven strategy. This update discusses the impact of this additional evidence and effective revisions.

Diagnosis and management of Aspergillus diseases: executive summary of the 2017 ESCMID-ECMM-ERS guideline

The European Society for Clinical Microbiology and Infectious Diseases, the European Confederation of Medical Mycology and the European Respiratory Society Joint Clinical Guidelines focus on diagnosis and management of aspergillosis. Of the numerous recommendations, a few are summarized here. Chest computed tomography as well as bronchoscopy with bronchoalveolar lavage (BAL) in patients with suspicion of pulmonary invasive aspergillosis (IA) are strongly recommended. For diagnosis, direct microscopy, preferably using optical brighteners, histopathology and culture are strongly recommended. Serum and BAL galactomannan measures are recommended as markers for the diagnosis of IA. PCR should be considered in conjunction with other diagnostic tests. Pathogen identification to species complex level is strongly recommended for all clinically relevant Aspergillus isolates; antifungal susceptibility testing should be performed in patients with invasive disease in regions with resistance found in contemporary surveillance programmes. Isavuconazole and voriconazole are the preferred agents for first-line treatment of pulmonary IA, whereas liposomal amphotericin B is moderately supported. Combinations of antifungals as primary treatment options are not recommended. Therapeutic drug monitoring is strongly recommended for patients receiving posaconazole suspension or any form of voriconazole for IA treatment, and in refractory disease, where a personalized approach considering reversal of predisposing factors, switching drug class and surgical intervention is also strongly recommended. Primary prophylaxis with posaconazole is strongly recommended in patients with acute myelogenous leukaemia or myelodysplastic syndrome receiving induction chemotherapy. Secondary prophylaxis is strongly recommended in high-risk patients. We strongly recommend treatment duration based on clinical improvement, degree of immunosuppression and response on imaging.

Economic analysis of empiric versus diagnostic-driven strategies for immunocompromised patients with suspected fungal infections in the People's Republic of China

Invasive fungal infections (IFIs) require rapid diagnosis and treatment. A decision-analytic model was used to estimate total costs and survival associated with a diagnostic-driven (DD) or an empiric treatment approach in neutropenic patients with hematological malignancies receiving chemotherapy or autologous/allogeneic stem cell transplants in Shanghai, Beijing, Chengdu, and Guangzhou, the People’s Republic of China. Treatment initiation for the empiric approach occurred after clinical suspicion of an IFI; treatment initiation for the DD approach occurred after clinical suspicion and a positive IFI diagnostic test result. Model inputs were obtained from the literature; treatment patterns and resource use were based on clinical opinion. Total costs were lower for the DD versus the empiric approach in Shanghai (¥3,232 vs ¥4,331), Beijing (¥3,894 vs ¥4,864), Chengdu, (¥4,632 vs ¥5,795), and Guangzhou (¥8,489 vs ¥9,795). Antifungal administration was lower using the DD (5.7%) than empiric (9.8%) approach, with similar survival rates. Results from one-way and probabilistic sensitivity analyses were most sensitive to changes in diagnostic test sensitivity and IFI incidence; the DD approach dominated the empiric approach in 88% of scenarios. These results suggest that a DD compared to an empiric treatment approach in the People’s Republic of China may be cost saving, with similar overall survival in immunocompromised patients with suspected IFIs.

Invasive aspergillosis in near drowning nonneutropenic patient

Invasive aspergillosis in immunosuppressed people has been well documented, but to diagnose and treat in an immunocompetent individual after near drowning, it requires early suspicion and proper empirical treatment. We report a case diagnosed to have invasive aspergillosis with systemic dissemination of the infection to the brain, gluteal muscles, and kidneys after a fall in a chemical tank of a paper manufacturing company. He was ventilated for acute respiratory distress syndrome and managed with antibiotics and vasopressors. Due to nonresolving pneumonia and positive serum galactomannan, trans-tracheal biopsy was performed which confirmed invasive aspergillosis and was treated with antifungals. With the availability of galactomannan assay and better radiological investigative modalities, occurrence of such invasive fungal infections in cases of drowning patients should be considered early in such patients and treated with appropriate antifungals.

Invasive fungal infections in pediatric hematopoietic stem cell transplant patients

BACKGROUND

Pediatric hematopoietic stem cell transplant (HSCT) recipients are at high risk of invasive fungal infections (IFIs).

METHODS

To characterize IFIs and changes in fungal organisms over time in pediatric HSCT patients, we performed a retrospective cohort study of all HSCTs performed in pediatric patients at UCLA between 1991 and 2006.

RESULTS

In all, 318 patients underwent 324 HSCT transplants over the 15-year period and 69 unique fungal infections were identified in 47 transplant patients. The overall incidence of fungal infections in HSCT recipients was 14.5%, with predominant organisms including Candida species (51%) and Aspergillus species (26%), with Candida albicans accounting for 18.8% of all fungal species. The distribution of organisms over time demonstrated a strong trend towards an increase in rare molds in more recent years. The respiratory tract was the main site of infection (52.6%), with urine and blood also noted as significant sites. Of all deaths in the patients with IFIs, fungal-related mortality accounted for 67.6% of deaths.

CONCLUSIONS

HSCT patients have a much higher risk of fungal infections with rarer organisms becoming more prevalent, a finding likely linked to evolving antifungal practices over time. This emphasizes the need for the development and implementation of improved diagnostic, prophylactic, and therapeutic strategies to improve patient survival.

Analysis of short-term prognostic factors in patients with hepatitis B virus-related liver failure

AIM: To investigate the risk factors that influence short-term (3 mo) prognosis in patients with hepatitis B virus (HBV)-related liver failure and to establish a prognostic model.

METHODS: A retrospective analysis of 137 patients with HBV-related liver failure treated at the First Affiliated Hospital of Soochow University from June 2005 to September 2008 was performed to observe their 3-month survival. The t-test, chi-square test and logistic regression analysis were used to identify independent risk factors affecting 3-month prognosis in these patients.

RESULTS: Of the 137 patients with HBV-related liver failure, 86 (63.8%) were alive and 51 (36.2%) died. Univariate analyses indicated that age, 1iver cirrhosis, total bilirubin (TBil), albumin (ALB), platelet ,international normalized ratio (INR), MELD, Child-Pugh, complicating hepatic encephalopathy, hepatorenal syndrome, pulmonary fungal infection, variceal bleeding, ascites, and spontaneous bacterial peritonitis were significant risk factors affecting 3-month prognosis in patients with HBV-related liver failure (P = 0.035, 0.001, 0.001, 0.001, 0.001, 0.001, 0.001, 0.001, 0.001, 0.001, 0.001, 0.001, 0.001, 0.001, respectively). Multivariate Logistic regression analyses demonstrated that age, INR, hepatic encephalopathy, and pulmonary fungal infection were independent risk factors affecting 3-month prognosis in these patients.

CONCLUSION: Age, INR, hepatic encephalopathy, and pulmonary fungal infection are independent risk factors affecting short-term prognosis in patients with HBV-related liver failure.

Diagnosis of invasive fungal infections in hematology and oncology--guidelines from the Infectious Diseases Working Party in Haematology and Oncology of the German Society for Haematology and Oncology (AGIHO)

Invasive fungal infections (IFIs) are a primary cause of morbidity and mortality in patients with hematological malignancies. Establishing a definite diagnosis of IFI in immunocompromised patients is particularly challenging and time consuming, but delayed initiation of antifungal treatment increases mortality. The limited overall outcome has led to the strategy of initiating either 'empirical' or 'preemptive' antifungal therapy before the final diagnosis. However, diagnostic procedures have been vastly improved in recent years. Particularly noteworthy is the introduction of newer imaging techniques and non-culture methods, including antigen-based assays, metabolite detection and molecular detection of fungal DNA from body fluid samples. Though varying widely in cancer patients, the risk of IFI is highest in those with allogeneic stem cell transplantation and those with acute leukemia. The AGIHO presents recommendations for the diagnosis of IFIs with risk-adapted screening concepts for febrile episodes in patients with haemato-oncological disorders.

The diagnostic value of halo and reversed halo signs for invasive mold infections in compromised hosts

The halo sign is a CT finding of ground-glass opacity surrounding a pulmonary nodule or mass. The reversed halo sign is a focal rounded area of ground-glass opacity surrounded by a crescent or complete ring of consolidation. In severely immunocompromised patients, these signs are highly suggestive of early infection by an angioinvasive fungus. The halo sign and reversed halo sign are most commonly associated with invasive pulmonary aspergillosis and pulmonary mucormycosis, respectively. Many other infections and noninfectious conditions, such as neoplastic and inflammatory processes, may also manifest with pulmonary nodules associated with either sign. Although nonspecific, both signs can be useful for preemptive initiation of antifungal therapy in the appropriate clinical setting. This review aims to evaluate the diagnostic value of the halo sign and reversed halo sign in immunocompromised hosts and describes the wide spectrum of diseases associated with them.

Yield of diagnostic procedures for invasive fungal infections in neutropenic febrile patients with chest computed tomography abnormalities

Haematological patients with neutropenic fever are frequently evaluated with chest computed tomography (CT) to rule out invasive fungal infections (IFI). We retrospectively analysed data from 100 consecutive patients with neutropenic fever and abnormal chest CT from 1998 to 2005 to evaluate their chest CT findings and the yield of diagnostic approaches employed. For their initial CTs, 79% had nodular opacities, with 24.1% associated with the halo sign. Other common CT abnormalities included pleural effusions (48%), ground glass opacities (37%) and consolidation (31%). The CT findings led to a change in antifungal therapy in 54% of the patients. Fifty-six patients received diagnostic procedures, including 46 bronchoscopies, 25 lung biopsies and seven sinus biopsies, with a diagnostic yield for IFI of 12.8%, 35.0% and 83.3%, respectively. In conclusion, chest CT plays an important role in the evaluation of haematological patients with febrile neutropenia and often leads to a change in antimicrobial therapy. Pulmonary nodules are the most common radiological abnormality. Sinus or lung biopsies have a high-diagnostic yield for IFI as compared to bronchoscopy. Patients with IFI may not have sinus/chest symptoms, and thus, clinicians should have a low threshold for performing sinus/chest imaging, and if indicated and safe, a biopsy of the abnormal areas.

Management of invasive aspergillosis in patients with COPD: rational use of voriconazole

Invasive pulmonary aspergillosis (IPA) is an important cause of mortality in patients with hematologic malignancies. The reported incidence of IPA in the context of chronic obstructive pulmonary disease (COPD) seems to increase. Approximately 1%-2% of overall fatal cases of IPA occur in COPD patients. The combination of factors such as lung immune imbalance, long-term corticosteroid use, increasing rate of bacterial exacerbations over time, and malnutrition are responsible for the emergence of IPA in these patients. The diagnosis of IPA is difficult to establish, which explains the delay in implementing accurate antifungal therapy and the high mortality rate. Persistent pneumonia nonresponsive to appropriate antibiotic treatment raises the concern of an invasive fungal infection. Definite diagnosis is obtained from tissue biopsy evidencing Aspergillus spp. on microscopic examination or in culture. Culture and microscopy of respiratory tract samples have a sensitivity and specificity of around 50%. Other diagnostic tools can be useful in documenting IPA: computed tomography (CT) scan, nonculture-based tests in serum and/or in bronchoalveolar lavage such as antibody/antigen tests for Aspergillus spp. More recent tools such as polymerase chain reaction or [1-->3]-beta-D-glucan have predictive values that need to be further investigated in COPD patients. Antifungal monotherapy using azole voriconazole is recommended as a first-line treatment of IPA. This review assesses the use of voriconazole in COPD patients.

Assessment of the clinical utility of serial β-d-glucan concentrations in patients with persistent neutropenic fever

The performance of the Fungitell assay was investigated in 100 patients with haematological malignancy undergoing chemotherapy who developed antibiotic-unresponsive neutropenic fever (AUNF). Serum β-d-glucan (BG) concentrations were significantly elevated on the first day of AUNF and all subsequent alternate days to day 10 in 38 patients who developed an invasive fungal infection (IFI) compared to 42 patients remaining free of such infections. The mean and median values of BG were 171.9±29.6 and 95.8 pg ml−1, respectively, for patients with IFI and 64.4±17.1 and 32.9 pg ml−1 for patients with only AUNF (P<0.0001). The differences remained significant over the 10 days despite antifungal therapy. The occurrence of ≥2 sequential concentrations of ≥80 pg ml−1 (‘positive’ test) was found to give the best overall option for diagnosis, with an accuracy of 81.3 %, sensitivity of 86.8 %, positive predictive value of 76.7 % and negative predictive value of 86.5 %. Of the patients with an IFI, 78 % developed a positive test at or before the clinical diagnosis was made – this occurred at a mean (range) of 1.25 (−14 to +14) days prior to the IFI diagnosis. By starting sampling of blood from the first day of neutropenia rather than from the first day of AUNF, 50 % of the patients with subsequent IFI would have been identified 5 days earlier. Increasing sampling to daily from alternate-day frequency did not further improve this earlier timing of an IFI diagnosis. A greater proportion of patients with persistent high levels of BG without overt IFI had severe enterocyte damage or mucositis than those with lower levels of BG without IFI (P=0.002). If the results of the initial BG test had been acted on to change antifungal therapy, discontinuation would have been inappropriate in 30 % of patients and would have delayed definitive antifungal therapy. Although the findings for the cohort of patients studied are very useful, there is inter-patient variability in the test's performance. An holistic diagnostic approach is therefore necessary to interpret the test results optimally. Future studies should address this in further detail as well as the impact of empirical antifungal drug use and patient outcome.

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.

Nosocomial fungal infections: epidemiology, diagnosis, and treatment

Invasive fungal infections are increasingly common in the nosocomial setting. Furthermore, because risk factors for these infections continue to increase in frequency, it is likely that nosocomial fungal infections will continue to increase in frequency in the coming decades. The predominant nosocomial fungal pathogens include Candida spp., Aspergillus spp., Mucorales, Fusarium spp., and other molds, including Scedosporium spp. These infections are difficult to diagnose and cause high morbidity and mortality despite antifungal therapy. Early initiation of effective antifungal therapy and reversal of underlying host defects remain the cornerstones of treatment for nosocomial fungal infections. In recent years, new antifungal agents have become available, resulting in a change in standard of care for many of these infections. Nevertheless, the mortality of nosocomial fungal infections remains high, and new therapeutic and preventative strategies are needed.

Imaging findings in acute invasive pulmonary aspergillosis: clinical significance of the halo sign

BACKGROUND

Computed tomography (CT) of the chest may be used to identify the halo sign, a macronodule surrounded by a perimeter of ground-glass opacity, which is an early sign of invasive pulmonary aspergillosis (IPA). This study analyzed chest CT findings at presentation from a large series of patients with IPA, to assess the prevalence of these imaging findings and to evaluate the clinical utility of the halo sign for early identification of this potentially life-threatening infection.

METHODS

Baseline chest CT imaging findings from 235 patients with IPA who participated in a previously published study were systematically analyzed. To evaluate the clinical utility of the halo sign for the early identification and treatment of IPA, we compared response to treatment and survival after 12 weeks of treatment in 143 patients who presented with a halo sign and in 79 patients with other imaging findings.

RESULTS

At presentation, most patients (94%) had > or =1 macronodules, and many (61%) also had halo signs. Other imaging findings at presentation, including consolidations (30%), infarct-shaped nodules (27%), cavitary lesions (20%), and air-crescent signs (10%), were less common. Patients presenting with a halo sign had significantly better responses to treatment (52% vs. 29%; P<.001) and greater survival to 84 days (71% vs. 53%; P<.01) than did patients who presented with other imaging findings.

CONCLUSIONS

Most patients presented with a halo sign and/or a macronodule in this large imaging study of IPA. Initiation of antifungal treatment on the basis of the identification of a halo sign by chest CT is associated with a significantly better response to treatment and improved survival.

An open study of the comparative efficacy and safety of caspofungin and liposomal amphotericin B in treating invasive fungal infections or febrile neutropenia in patients with haematological malignancy

In a clinical non-trial setting, the efficacy and safety of caspofungin was compared with liposomal amphotericin B for the management of febrile neutropenia or invasive fungal infections in 73 episodes in patients with haematological malignancy. There were fewer episodes of drug toxicity with caspofungin than liposomal amphotericin B (58.3 vs 83.7 %, P=0.02). The favourable response rate for episodes of febrile neutropenia treated with caspofungin or liposomal amphotericin B was similar at 37.5 and 53.8 %, respectively, but more breakthrough fungal infections occurred with caspofungin than with liposomal amphotericin B (33.3 vs 0 %, P<0.05) in these patients who did not receive antifungal prophylaxis. None of four episodes of candidaemia or hepatosplenic candidiasis responded to caspofungin compared with three of four episodes treated with liposomal amphotericin B. Mortality was significantly higher with caspofungin treatment compared with liposomal amphotericin B (6/24 vs 2/49, P=0.01), mainly due to an excess of fungal infections (P=0.04). Caspofungin treatment was a significant independent predictor of mortality [odds ratio=7.6 (95 % confidence interval 1.2-45.5)] when sepsis severity, prolonged neutropenia and length of antifungal therapy were considered in a multiple logistic regression model. In clinical practice, there is a suggestion that caspofungin may not be as effective as liposomal amphotericin B in preventing breakthrough invasive fungal infections in febrile neutropenia or in preventing fungus-related deaths. Because of the potential biases in this observational study, these preliminary findings should be interpreted with caution and clarified with a larger cohort of patients.

[Fungal infection following reduced-intensity stem cell transplantation (RIST)]

Hematopoietic stem cell transplantation has been established as a curative treatment for advanced hematologic malignancies. Transplantation with a reduced-intensity conditioning regimen has been developed, and the minimal toxicity of reduced-intensity stem cell transplantation (RIST) has made this procedure available for patients of advanced age or with organ dysfunction. The response of malignant lymphoma and some solid tumors to RIST has been observed. RIST with unrelated donors and umbilical cord blood has been studied. Fungal infection is an important complication of RIST. Since the prognosis of fungal infection is poor, the management has been focused on its prophylaxis. Given recent progression in RIST management, the strategy of infectious prophylaxis has also changed. Equipment in the hospital is important for fungal infection; however, the median day of the development of fungal infection is day 100, when most patients are followed as outpatients. The focus of fungal management after RIST is oral antifungal agents rather than in-hospital equipment. Various antifungal agents have recently been developed and applied for clinical use, and many of these have been developed simultaneously for the first time. A major change in antifungal management will probably occur in the next several years.

Clinical and radiologic predictors of invasive pulmonary aspergillosis in cancer patients: should the European Organization for Research and Treatment of Cancer/Mycosis Study Group (EORTC/MSG) criteria be revised?

BACKGROUND

Invasive pulmonary aspergillosis (IPA) is a life-threatening infection in immunocompromised patients. The outcome of such infections depends on early diagnosis and prompt initiation of therapy. The objective of the current study was to determine the significant predictive factors that characterize IPA in patients with cancer.

METHODS

The clinical characteristics and computed tomography (CT) findings for 47 cases with IPA were retrospectively reviewed and compared with 49 controls (patients diagnosed on autopsy with nonfungal pneumonias). Data from all 96 patients were modeled using multivariate logistic regression. Subgroups of patients with common characteristics and outcomes were identified.

RESULTS

Leukemia, neutropenia, cavitation, and nodular lesions occurred significantly more often among cases than controls (P = 0.04, 0.004, 0.04, and 0.02, respectively). A quantitative scoring system was developed that could be used to identify patients as being at low, medium, and high risk for IPA.

CONCLUSIONS

IPA should be highly suspected in leukemia patients with profound neutropenia, pleuritic chest pain, and cavitary or nodular lesions detected on CT scan. These predictive factors can be used to indicate when early prophylactic and therapeutic antifungal interventions should be initiated.

Early diagnosis of invasive aspergillosis in infants and children

Effective management of invasive aspergillosis (IA) requires early and accurate diagnosis. Microscopy and culture of appropriate specimens remain the gold standard of mycological diagnosis. High-resolution computed tomography serially performed constitutes a sensitive mode of diagnosis of pulmonary IA in hematological patients, but similar data is lacking for children. While early diagnosis of IA has been improved with galactomannan assay in adults, its use is problematic in young infants due to specificity inferiority. Galactomannan testing also is characterized by low sensitivity in pediatric patients with primary immunodeficiencies including chronic granulomatous disease and Job's syndrome. Beta-D glucan assay has been studied in adult patients with fungal infections including IA. The high negative predictive value of the assay allows its use for excluding IA; no specific data, however, exist for children. Polymerase chain reaction (PCR) may be a powerful tool for early diagnosis of IA but has not been standardized for routine use yet. No studies address the issue in neonates, whereas in children PCR has not been specifically studied but is probably as good as in adults. A high degree of suspicion in immunodeficient pediatric hosts, suggestive clinical and radiological findings, as well as mycological data by application of multiple diagnostic methods including serology and molecular biology, are expected to enhance the capacity to diagnose IA in young patients.

Direct detection of angioinvasive pulmonary aspergillosis in immunosuppressed patients: preliminary results with high-resolution 16-MDCT angiography

OBJECTIVE

The aim of this study was to optimize detection of angioinvasive pulmonary aspergillosis by showing direct vessel involvement at a peripheral level with high-resolution MDCT angiography in patients with antibiotic-resistant fever of unknown origin under immunosuppression. Twelve CT angiographic examinations were prospectively performed in 10 patients with an optimized CT angiography protocol with 16-MDCT after IV administration of contrast agent using care bolus (Siemens Medical Solutions). Axial images and maximum intensity projections were evaluated for vascular occlusion by an experienced radiologist blinded to the clinical histories. Results were correlated with histology and clinical follow-up data including follow-up CT. Fourteen focal pulmonary lesions were detected by CT in eight patients. Eight of 14 lesions were confirmed by histology. In the remaining six lesions, diagnosis was made by clinical and CT follow-up. In nine of nine lesions in which angioinvasive infection was excluded, CT angiography showed patent vessels. In four of five lesions with histologically proven fungal angioinvasion, vascular occlusion was detected on CT angiography.

CONCLUSION

High-resolution MDCT angiography has been shown to be a feasible technique to depict directly vessel occlusion in the setting of suspected fungal infections, especially for early diagnosis of angioinvasive pulmonary aspergillosis in immunosuppressed patients.

Invasive fungal infections in pediatric oncology patients: 11-year experience at a single institution

The purpose of this study was to determine the incidence of fungal infections in pediatric hematology and oncology (PHO) patients and to describe variations regarding site of infection, organisms, and mortality. The records of 1,052 patients presenting to the UCLA PHO service with various malignancies from 1991 to 2001 were retrospectively reviewed. No patient received invasive antifungal prophylaxis. Transplant patients were excluded. The 11-year incidence of fungal infections in this pediatric oncology cohort was 4.9%. There was a linear increase in the incidence of fungal infections from 2.9% to 7.8% between 1996 and 2001 (P = 0.001). Patients with acute leukemia represented 36% of the population but had a disproportionate incidence (67%) of fungal infections. Adolescents had twice the expected incidence of infection (P < 0.0001). Overall, Candida sp. was the major pathogen. Over time, a trend of fewer infections caused by Candida and more due to Aspergillus was noted. Blood-borne infections decreased over time, while those in the urinary and respiratory tracts increased (P = 0.04). Sixty-two percent of infections occurred in neutropenic patients. PHO patients had an overall mortality of 21%, but those with fungal infections experienced a 2.6-fold higher mortality that was not attributable to infections alone. Empiric antifungal therapy had no effect on mortality rates. Concurrent nonfungal infections did not increase mortality rates. The incidence of fungal infections increased over time, possibly as a result of advances in antibacterial and chemotherapeutic regimens. Adolescents and patients with leukemia were especially at risk. Fungal infections are a poor prognostic factor, independent of fungal-related mortality. New diagnostic methods allowing for early detection and treatment as well as more effective therapies are needed.

New developments in antifungal strategy

The increasing importance of invasive fungal infection as a cause of severe morbidity and mortality in immunocompromised patients has fuelled the development of new antifungal agents, including new triazole agents and echinocandins. Failure to diagnose fungal infection adequately has hampered the evaluation of these drugs in clinical trials. Consequently, the evidence base behind many prophylactic and empirical treatment strategies has been poor. Recent advances have improved diagnostic criteria and opened the way for more rational usage of these expensive preparations. The proven efficacy and improved safety profile of newer agents is a major advantage. Furthermore, better understanding of the immune response may allow novel strategies of adjunctive therapy and immunomodulation.