Radiological findings of early invasive pulmonary aspergillosis in immune-compromised patients

Approach to Acute Respiratory Illness in Children with Hematological Malignancy: A Prospective Study Evaluating Utility of CT Scan

Introduction Various pulmonary complications can occur in children with hematological malignancies including both infection and malignant disease infiltration of pulmonary parenchyma.

Objectives To assess the role of CT scan in determining the etiology of acute pulmonary complications in children with hematological malignancies.

Materials and Methods All children < 17 years with newly diagnosed hematological malignancy with respiratory symptoms (Group A) along with children who developed fever with persistent respiratory symptoms as well as worsening chest radiographs during treatment (Group B) and underwent CECT thorax, from February 2019 to July 2020 were enrolled. The final diagnosis was made on the basis of clinical history, laboratory as well as radiological investigations and treatment response.

Results Thirty-seven children with mean age of 7.5 ± 3.5 years and male to female ratio of 1.3:1 who underwent CECT thorax were included in our study. For newly diagnosed cases, i.e., Group A (n = 8), the most common cause of respiratory symptoms as identified on CECT thorax was pulmonary tumoral infiltration (n = 5) followed by tuberculosis (n = 3). However, in Group B (n = 29) the cause of persistent respiratory symptoms was identified as infection (n = 17) followed by leukemic infiltration (n = 12). Thus, chest CT could accurately identify pulmonary tuberculosis, fungal pneumonia, bacterial infection, and pulmonary tumoral infiltrates.

Conclusion CT scan can be used as an adjunctive tool for prompt diagnosis and management of pulmonary complications in children with persistent respiratory symptoms as they are often non-specific.

Emerging Invasive Fungal Infections: Clinical Features and Controversies in Diagnosis and Treatment Processes

Background

The diagnosis and treatment of invasive fungal infection (IFI) are still challenging due to its complexity and non-specificity. This study was aimed to investigate the clinical features, diagnosis process, and outcomes of patients with emerging IFIs.

Methods

A retrospective review of emerging IFIs in adult patients at a university hospital in China was conducted; diagnoses were based on the criteria of EORTC/MSG 2008.

Results

145 IFI patients (pulmonary, intestinal and urinary) were enrolled in this study, including 80 proven (55.2%), 59 probable (40.7%), or 6 possible IFIs (4.1%). Among the 126 pulmonary IFIs, the positivity rate for sputum microscopy, sputum culture, and 1.3-ß-D-glucan (BG) test was 54.0%, 44.4%, and 37.3%, respectively. Among the 19 intestinal and urinary IFIs, routine examination of stool or urine and their culture were the main methods of detection. Positive results of 75 detected fungal strains from the samples showed that 30 cases were complicated with one or more bacterial infections. The average length of hospital stay of IFI patients was 14.0 (10.0, 20.0) days. The time from admission to antifungal therapy initiation (P<0.001), liver cirrhosis (P<0.001), hematological tumor (P<0.001), coinfection (P=0.019) and immune diseases (P=0.025) were independent predictors of prolonged hospitalization.

Conclusion

Delayed time was the primary predictor of prolonged hospitalization. This prediction is suggested to improve IFI diagnostic and therapeutic process of IFI to promote prognosis.

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.

ACR Appropriateness Criteria® Acute Respiratory Illness in Immunocompromised Patients

The immunocompromised patient with an acute respiratory illness (ARI) may present with fever, chills, weight loss, cough, shortness of breath, or chest pain. The number of immunocompromised patients continues to rise with medical advances including solid organ and stem cell transplantation, chemotherapy, and immunomodulatory therapy, along with the continued presence of human immunodeficiency virus and acquired immunodeficiency syndrome. Given the myriad of pathogens that can infect immunocompromised individuals, identifying the specific organism or organisms causing the lung disease can be elusive. Moreover, immunocompromised patients often receive prophylactic or empiric antimicrobial therapy, further complicating diagnostic evaluation. Noninfectious causes for ARI should also be considered, including pulmonary edema, drug-induced lung disease, atelectasis, malignancy, radiation-induced lung disease, pulmonary hemorrhage, diffuse alveolar damage, organizing pneumonia, lung transplant rejection, and pulmonary thromboembolic disease. As many immunocompromised patients with ARI progress along a rapid and potentially fatal course, timely selection of appropriate imaging is of great importance in this setting. The American College of Radiology Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed annually by a multidisciplinary expert panel. The guideline development and revision include an extensive analysis of current medical literature from peer reviewed journals and the application of well-established methodologies (RAND/UCLA Appropriateness Method and Grading of Recommendations Assessment, Development, and Evaluation or GRADE) to rate the appropriateness of imaging and treatment procedures for specific clinical scenarios. In those instances where evidence is lacking, or equivocal, expert opinion may supplement the available evidence to recommend imaging or treatment.

Practice Guidelines for the Diagnosis and Management of Aspergillosis: 2016 Update by the Infectious Diseases Society of America

It is important to realize that guidelines cannot always account for individual variation among patients. They are not intended to supplant physician judgment with respect to particular patients or special clinical situations. IDSA considers adherence to these guidelines to be voluntary, with the ultimate determination regarding their application to be made by the physician in the light of each patient's individual circumstances.

Histopathological implications of Aspergillus infection in lung

This paper opens with a discussion on the significance of invasive fungal infections in advanced contemporary medicine, with an emphasis on the intractability of disease management and the difficulties of diagnosis. This is followed by a discussion concerning classification, histopathological features, and pathophysiology. While it has been largely accepted that Aspergillus species is recognized by cellular receptors and attacked by neutrophils, the radiological and macroscopic findings linking infection with neutropenia remain unconfirmed. In an effort to gain a better understanding of the pathophysiology and pathogenesis of invasive aspergillosis, we wish to emphasize the utility of radiological and histopathological examinations since these can provide detailed information on the extremely complex interaction between the causative microbes and tissue responses. A review of noninvasive or semi-invasive aspergillosis is also provided, with particular emphasis on chronic necrotizing pulmonary aspergillosis, which is recognized as a transition form of simple pulmonary aspergilloma and invasive pulmonary aspergillosis, although few findings have been reported in this area.

Successfully treated invasive pulmonary aspergillosis in a patient with diabetic ketoacidosis

We report herein a case of diabetic ketoacidosis associated with invasive aspergillosis that was successfully treated with liposomal amphotericin-B (L-AMB). Early intervention after confirming the diagnosis of invasive pulmonary aspergillosis is very important, and initiating early treatment with L-AMB can lead to a full recovery.

Lung resection in hematologic patients with pulmonary invasive fungal disease

BACKGROUND

Pulmonary invasive fungal disease is a frequent complication in patients with hematologic malignancies. Surgical resection in addition to antifungal therapy is an option for selected cases but often feared because of immunosuppression.

METHODS

We analyzed the outcome of 71 patients undergoing lung resection for pulmonary invasive fungal disease. Most patients had leukemia, 44 underwent high-dose chemotherapy, and 18 underwent stem cell transplantation.

RESULTS

On the day of surgery, 44 patients were neutropenic, and 41 had a platelet count < 50 × 109/L. Forty-five nonanatomic (atypical) resections and 26 lobectomies were performed. Fungal infection was histologically proven in 53 patients. Reoperation was needed in four patients (bronchial stump dehiscence, persistent air leak, chylothorax, and seroma). Minor complications at the site of surgery occurred in 14 patients. In only two, there was an uncontrolled disseminated fungal infection. Overall, mortality at 30 days was 7% (five of 71). Long-term survival was mainly influenced by the underlying hematologic disease.

CONCLUSIONS

Lung resection is a therapeutic option for hematologic patients with pulmonary fungal infection. Despite immunosuppression, the perioperative morbidity and mortality is acceptable, and, therefore, the prognosis is not determined by the surgical intervention.

Imaging pneumonia in immunocompetent and immunocompromised individuals

PURPOSE OF REVIEW

The article aims to indicate the current role of radiological imaging in immune competent and immunocompromised patients with pneumonia. The radiological findings in the most common conditions will be reviewed.

RECENT FINDINGS

Three basic patterns of radiographic abnormality are recognized: lobar (nonsegmental) pneumonia; bronchopneumonia (lobular pneumonia); and interstitial pneumonia. The chest radiograph remains the initial radiological investigation. Computed tomography (CT) is more sensitive than the chest radiograph. The appearances on CT with certain infections such as mycoplasma, invasive aspergillosis, and pneumocystis, in the appropriate clinical setting, may allow a treatment decision to be made when obtaining fluid or tissue for culture is problematical. MRI technology is advancing and this technique may provide an option for follow-up of chronic disease in younger patients in whom radiation exposure is a concern, but MRI does not yet match CT as a diagnostic test in this field.

SUMMARY

Radiology retains a key role in diagnosing pneumonia, excluding pneumonia, following up patients to check for resolution and to evaluate potential complications. The chest radiograph remains the initial examination. CT is more sensitive and with certain infections more specific. MRI provides an option for monitoring progress, although cannot yet match CT as an initial diagnostic test.

Radiological and clinical findings of 25 patients with invasive pulmonary aspergillosis: retrospective analysis of 2150 liver transplantation cases

OBJECTIVE

The purpose of this study was to evaluate the radiological and clinical findings of invasive pulmonary aspergillosis (IPA) after liver transplantation.

METHODS

This study included 25 consecutive liver transplant recipients with histologically confirmed IPA after liver transplantation. Radiological examinations performed for diagnosis were available in all patients. Clinical findings and changes in clinical response and radiological findings after treatment were also evaluated.

RESULTS

3 main radiological findings were identified: nodules, 64% (16/25); masses, 36% (9/25); and consolidations in a patchy pattern, 20% (5/25). A tree-in-bud pattern was found in 12% (3/25) of patients. In 8 (32%) of 25 patients, we found a combination of 2 or more of these signs: 5 (20%) patients presented with concurrent nodules accompanied by patchy consolidations and/or tree-in-bud, and 3 (12%) patients showed masses accompanied by large consolidations. A halo sign was observed in 20 (80%) of 25 patients. Hypodense sign and cavitary lesions were encountered in 17 (68%) of 25 patients. Follow-up radiological findings after treatment showed improvement in 18 patients, no change in 4 patients and progression in 3 patients. There were three aspergillosis-associated deaths during the follow-up period. The onset time of IPA was a median of 31 days after transplantation. The most common symptom at diagnosis was fever (n=15). None of the 25 patients had leukopaenia at the time of the diagnosis of IPA.

CONCLUSIONS

The most common radiological findings of IPA after liver transplantation are multiple nodules with or without halo sign, masses and consolidations, which usually appear about 1 month after transplantation.

Imaging studies for diagnosing invasive fungal pneumonia in immunocompromised patients

PURPOSE OF REVIEW

The aim is to review imaging advances in invasive fungal pneumonia in cancer and transplant recipients and how their use can help guide treatment.

RECENT FINDINGS

Early chest computed tomographic (CT) imaging of immunocompromised patients with neutropenic fever leads to improved survival. Some of the typical CT findings of invasive fungal pneumonia are transitory and are most common during the first week of symptoms. The reversed halo sign, an early sign of disease, is more common in mucormycosis. During the first 10 days of infection, invasive fungal pneumonia nodules may grow on follow-up CT scans, but this does not necessarily equate to worsening disease. Because of the excessive radiation of chest CT and because pulmonary nodule size typically expands during the first few weeks of treatment, follow-up CT scans should be ordered only when therapy changes are dependent on imaging findings.

SUMMARY

Early chest CT imaging in immunocompromised patients suspected of having invasive fungal pneumonia can help identify disease early, leading to improved outcome.

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.

Early Diagnosis of Invasive Aspergillosis in Neutropenic Patients. Comparison between Serum Galactomannan and Polymerase Chain Reaction

Background:

Invasive aspergillosis (IA) is a major cause of morbidity and mortality in profoundly neutropenic patients, so early diagnosis is mandatory.

Aim:

Consecutive patients with hematological malignancies undergoing intensive chemotherapy were screened for IA with two different methods which were compared.

Methods:

From October 2000 to August 2003 we tested 1311 serum samples from 172 consecutive patients with a polymerase chain reaction assay and between April 2005 and April 2008 we tested 806 serum samples from 169 consecutive patients with a Galactomannan (GM) test. Bronchoalveolar (BAL) samples were obtained whenever the patient’s condition allowed and tested with either method.

Results:

The serum PCR assay had a sensitivity of 75.0% and a specificity of 91.9% and the serum GM assay had a sensitivity of 87.5% and a specificity of 93.1%, (P > 0.05). The presence of two or more consecutive positive serum samples was predictive of IA for both assays. BAL GM/PCR was positive in some patients without serum positivity and in patients with 2 or more positive serum GM/PCR.

Conclusions:

No significant differences between the 2 serum tests were found. The GM assay has the advantage of being standardized among several laboratories and is incorporated in the criteria established by the European Organization for Research and Treatment of Cancer/Invasive Fungal Infections Cooperative Group and the National Institute of Allergy and Infectious Diseases Mycosis Study Group (EORTC/MSG), however is much more expensive. BAL GM and PCR sampling aids in IA diagnosis but needs further validation studies to differentiate between colonization and true infection in cases where serum GM or PCR are negative.