How I manage pulmonary nodular lesions and nodular infiltrates in patients with hematologic malignancies or undergoing hematopoietic cell transplantation

How I manage acute respiratory failure in patients with hematological malignancies

ABSTRACT

Acute respiratory failure (ARF) is common in patients with hematological malignancies notably those with acute leukemia, myelodysplastic syndrome, or allogeneic stem cell transplantation. ARF is the leading reason for intensive care unit (ICU) admission, with a 35% case fatality rate. Failure to identify the ARF cause is associated with mortality. A prompt, well-designed diagnostic workup is crucial. The investigations are chosen according to pretest diagnostic probabilities, estimated by the DIRECT approach: D stands for delay, or time since diagnosis; I for pattern of immune deficiency; R and T for radiological evaluation; E refers to clinical experience, and C to the clinical picture. Thorough familiarity with rapid diagnostic tests helps to decrease the use of bronchoscopy with bronchoalveolar lavage, which can cause respiratory status deterioration in those patients with hypoxemia. A prompt etiological diagnosis shortens the time on unnecessary empirical treatments, decreasing iatrogenic harm and costs. High-quality collaboration between intensivists and hematologists and all crossdisciplinary health care workers is paramount. All oxygen delivery systems should be considered to minimize invasive mechanical ventilation. Treatment of the malignancy is started or continued in the ICU under the guidance of the hematologists. The goal is to use the ICU as a bridge to recovery, with the patient returning to the hematology ward in sufficiently good clinical condition to receive optimal anticancer treatment.

The Challenge of Diagnosing Invasive Pulmonary Aspergillosis in Children: A Review of Existing and Emerging Tools

Invasive pulmonary aspergillosis remains a major cause of morbidity and mortality for immunocompromised children, particularly for patients with acute leukaemia and those undergoing haematopoietic stem cell transplantation. Timely diagnosis, using a combination of computed tomography (CT) imaging and microbiological testing, is key to improve prognosis, yet there are inherent challenges in this process. For CT imaging, changes in children are generally less specific than those reported in adults and recent data are limited. Respiratory sampling by either bronchoalveolar lavage or lung biopsy is recommended but is not always feasible in children, and serum biomarkers, including galactomannan, have important limitations. In this review we summarise the current paediatric data on available diagnostic tests for IPA and highlight key emerging diagnostic modalities with potential for future use.

The role of radiology in addressing the challenge of lung cancer after lung transplantation

The importance of lung cancer as a complication of lung transplantation is increasingly recognised. It may become an important survival-limiting factor in lung transplant patients as management of other complications continues to improve and utilisation of extended criteria donors grows. Radiology can play a key role in tackling this issue at multiple stages in the transplantation pathway and follow-up process. Routine chest CT as part of pre-transplant recipient assessment (and donor assessment if available) can identify suspicious lung lesions with high sensitivity and detect chronic structural lung diseases such as pulmonary fibrosis associated with an increased risk of malignancy post-transplant. Pre-transplant CT also provides a comparison for later CT studies in the assessment of nodules or masses. The potential role of regular chest CT for lung cancer screening after transplantation is less certain due to limited available evidence on its efficacy. Radiologists should be cognisant of how the causes of pulmonary nodules in lung transplant patients may differ from the general population, vary with time since transplantation and require specific recommendations for further investigation/follow-up as general guidelines are not applicable. As part of the multidisciplinary team, radiology is involved in an aggressive diagnostic and therapeutic management approach for nodular lung lesions after transplant both through follow-up imaging and image-guided tissue sampling. This review provides a comprehensive overview of available clinical data and evidence on lung cancer in lung transplant recipients, and in particular an assessment of the current and potential roles of pre- and post-transplant imaging. KEY POINTS: • Lung cancer after lung transplantation may become an increasingly important survival-limiting factor as mortality from other complications declines. • There are a number of important roles for radiology in tackling the issue which include pre-transplant CT and supporting an aggressive multidisciplinary management strategy where lung nodules are detected in transplant patients. • The introduction of routine surveillance chest CT after transplant in addition to standard clinical follow-up as a means of lung cancer screening should be considered.

Impact of Changes of the 2020 Consensus Definitions of Invasive Aspergillosis on Clinical Trial Design: Unintended Consequences for Prevention Trials?

Background

Consensus definitions for the diagnosis of invasive fungal diseases (IFDs) were updated in 2020 to increase the certainty of IFD for inclusion in clinical trials, for instance by increasing biomarker cutoff limits to define positivity. To date, there is a paucity of data as to the impact of the revised definitions on clinical trials.

Methods

In this study, we sought to determine the impact of the new definitions on classifying invasive aspergillosis (IA), the most common invasive mold disease in immunocompromised patients. We reclassified 226 proven and probable IA cases plus 139 possible IFD cases in the Aspergillus Technology Consortium (AsTeC) and in an antifungal prophylaxis trial (BMT CTN 0101) using the new criteria.

Results

Fewer cases met the more stringent diagnostic 2020 criteria after applying the reclassification criteria to define probable IA. Of 188 evaluable probable cases, 41 (22%) were reclassified to 40 possible IA and 1 probable IFD. Reclassification to possible IFD occurred in 22% of hematologic malignancy (HM) patients, 29% of hematopoietic cell transplant (HCT) patients, and in no lung transplant (LT) patients. Date of diagnosis was established a median (range) of 3 (1–105) days later in 15% of probable IA cases using the new criteria. Applying the new definitions to the BMT CTN 0101 trial, the power to detect the same odds ratio decreased substantially.

Conclusions

The updated IA consensus definitions may impact future trial designs, especially for antifungal prophylaxis studies.

Pulmonary Complications in Hematopoietic Stem Cell Transplant Recipients-A Clinician Primer

Hematopoietic stem cell transplants (HSCT) are becoming more widespread as a result of optimization of conditioning regimens and prevention of short-term complications with prophylactic antibiotics and antifungals. However, pulmonary complications post-HSCT remain a leading cause of morbidity and mortality and are a challenge to clinicians in both diagnosis and treatment. This comprehensive review provides a primer for non-pulmonary healthcare providers, synthesizing the current evidence behind common infectious and non-infectious post-transplant pulmonary complications based on time (peri-engraftment, early post-transplantation, and late post-transplantation). Utilizing the combination of timing of presentation, clinical symptoms, histopathology, and radiographic findings should increase rates of early diagnosis, treatment, and prognostication of these severe illness states.

Missed diagnosis and misdiagnosis of infectious diseases in hematopoietic cell transplant recipients: an autopsy study

Hematopoietic cell transplantation (HCT) is potentially curative for patients with hematologic disorders, but carries significant risks of infection-related morbidity and mortality. Infectious diseases are the second most common cause of death in HCT recipients, surpassed only by progression of underlying disease. Many infectious diseases are difficult to diagnose and treat, and may only be first identified by autopsy. However, autopsy rates are decreasing despite their value. The clinical and autopsy records of adult HCT recipients at our center who underwent autopsy between 1 January 2000 and 31 December 2017 were reviewed. Discrepancies between premortem clinical diagnoses and postmortem autopsy diagnoses were evaluated. Of 185 patients who underwent autopsy, 35 patients (18.8%) had a total of 41 missed infections. Five patients (2.7%) had >1 missed infection. Of the 41 missed infections, 18 (43.9%) were viral, 16 (39.0%) were fungal, 5 (12.2%) were bacterial, and 2 (4.9%) were parasitic. According to the Goldman criteria, 31 discrepancies (75.6%) were class I, 5 (12.2%) were class II, 1 (2.4%) was class III, and 4 (9.8%) were class IV. Autopsies of HCT recipients frequently identify clinically significant infectious diseases that were not suspected premortem. Had these infections been suspected, a change in management might have improved patient survival in many of these cases. Autopsy is underutilized and should be performed regularly to help improve infection-related morbidity and mortality. Illustrative cases are presented and the lessons learned from them are also discussed.

Clinical Usefulness of Bronchoalveolar Lavage in the Management of Pulmonary Infiltrates in Adults with Hematological Malignancies and Stem Cell Transplantation

Introduction

Pulmonary complications are frequent in patients with hematologic malignancies and stem cell transplantation. Regardless of the microbiological usefulness of bronchoalveolar lavage (BAL), little information exists on both its benefits as a guide for therapeutic decisions and its impact on patients’ clinical outcome.

Methods

A prospective observational single-center study was performed between July 2011 and July 2016. Consecutive episodes of pulmonary infiltrates were analyzed in subjects over 18 years of age who presented hematologic malignancies and underwent chemotherapy or stem cell transplantation.

Results

Ninety-six episodes of pulmonary infiltrates were analyzed. Acute leukemia was the most frequent underlying condition. Thirty-seven patients (38.5%) received a stem cell transplant. Sixty-one (62.9%) were neutropenic at the moment of inclusion in the study. A definitive etiologic diagnosis was obtained in 41 cases (42.7%), where infection accounted for the vast majority of cases (33 cases, 80.5%). Definitive diagnosis was reached by non-invasive methods in 13 cases (13.5%). BAL was performed in 47 cases and led to a diagnosis in 40.4% of the cases. BAL results led to therapeutic changes in 27 cases (57.4%), including the addition of new antimicrobials to empiric treatments in 10. Regarding BAL’s safety, two patients experienced minor adverse events and one a severe adverse event; no procedure-related deaths were observed.

Conclusions

Infection was the leading cause of pulmonary infiltrates in patients with hematologic malignancies and stem cell transplantation. BAL was a useful decision-making diagnostic tool, with minor adverse events.

Metagenomic Next-Generation Sequencing versus Traditional Pathogen Detection in the Diagnosis of Peripheral Pulmonary Infectious Lesions

Purpose

The aim of this study was to evaluate the value of metagenomic next-generation sequencing (mNGS) in peripheral pulmonary infection management by comparing the diagnostic yield of mNGS and traditional pathogen detection methods on interventional specimens obtained by bronchoscopy.

Patients and Methods

This study enrolled patients suspected with pulmonary infection who were admitted to Tianjin Medical University General Hospital from June 2018 to August 2019. Specimens were obtained from bronchoscopy for mNGS analysis and traditional pathogen detection (including bronchoalveolar lavage fluid microbial culture, smear microscopy, and lung biopsy histopathology), and the diagnostic yields were compared between mNGS and traditional methods to evaluate the diagnostic value of mNGS in peripheral pulmonary infection diagnosis.

Results

In this study, by comparing mNGS with traditional pathogen detection, the results indicated that, first, mNGS identified at least one microbial species in almost 89% of the patients with pulmonary infection; second, mNGS detected microbes related to human diseases in 94.49% of samples from pulmonary infection patients who had received negative results from traditional pathogen detection; third, the accuracy and sensitivity of mNGS are higher than those of traditional pathogen detection; and, finally, mNGS could simultaneously detect and identify a large variety of pathogens.

Conclusion

Metagenomic NGS analysis provided fast and precise pathogen detection and identification, contributing to prompt and accurate treatment of peripheral pulmonary infection.

CT-guided Core-Needle Biopsy of the Lung Is Safe and More Effective than Fine-Needle Aspiration Biopsy in Patients with Hematologic Malignancies

Purpose

To evaluate the safety and diagnostic yield of CT-guided core-needle biopsy (CNB) versus fine-needle aspiration biopsy (FNAB) of lung nodules and masses in patients with hematologic malignancies (HMs).

Materials and Methods

With institutional review board approval, 166 patients were retrospectively reviewed between 2007 and 2017 who were diagnosed with leukemia, lymphoma, or myelodysplastic syndromes (with or without hematopoietic stem cell transplant) and who underwent CT-guided FNAB and/or CNB of the lung. Patient medical records, pathologic reports, and interventional biopsy reports were reviewed.

Results

In the study period, 166 patients underwent percutaneous CT-guided lung biopsy; 36% (60 of 166) of the procedures included CNB (CNB + FNAB and CNB only), whereas 64% (106 of 166) were FNAB only. In the CNB group, FNAB was also performed for 92% (55 of 60) of the patients before CNB; 13% (eight of 60) of patients in the CNB group were nondiagnostic versus 45% (48 of 106) of FNAB only (P < .0001). There was no statistically significant difference in the pulmonary complication rates, with 1.7% of CNB and 1.9% of FNAB only requiring chest tube placement (P = .7), 5% of CNB and 2.8% of FNAB only developing hemoptysis (P = .4), and 5% of CNB and 2% of FNAB only developing hemothorax (P = .3). A change in clinical management was observed in 51% of patients with diagnostic biopsies compared with 21% of patients with nondiagnostic biopsies (P = .0002).

Conclusion

CT-guided CNB is an effective technique for performing lung biopsy in patients with HMs with higher diagnostic yield compared with FNAB, and a higher, although not a statistically significant, increased risk of bleeding complications and pneumothorax.© RSNA, 2019See also the commentary by Elicker in this issue.

A bronchoalveolar lavage-driven antimicrobial treatment improves survival in hematologic malignancy patients with detected lung infiltrates: A prospective multicenter study of the SEIFEM group

Bronchoalveolar lavage (BAL) is recommended for diagnosing lung infiltrates (LI) in patients with hematologic malignancy (HM). Prospective data on the impact of BAL on survival are still lacking. We conducted a prospective observational study on patients who performed BAL for LI among 3055 HM patients hospitalized from January to September 2018. The BAL was performed in 145 out of 434 patients who developed LI, at a median time of four days from LI detection. The median age was 60 (1-83). Most patients had an acute myeloid leukemia/myelodisplastic syndrome (81), followed by lymphoma (41), acute lymphoblastic leukemia (27), and other types of HM (36). A putative causal agent was detected in 111 cases (76%), and in 89 cases (61%) the BAL results provided guidance to antimicrobial treatment. We observed a significantly improved outcome of LI at day +30 in patients who could receive a BAL-driven antimicrobial treatment (improvement/resolution rate: 71% vs 55%; P = .04). Moreover, we observed a significantly improved outcome in 120-day overall survival (120d-OS) (78% vs 59%; P = .009) and 120-day attributable mortality (120d-AM) (11% vs 30%; P = 0.003) for patients who could receive a BAL-driven treatment. The multivariate analysis showed that BAL-driven antimicrobial treatment was significantly associated with better 120d-OS and lower 120d-AM. We did not observe any severe adverse events. In conclusion BAL allows detection of a putative agent of LI in about 75% of cases, it is feasible and well tolerated in most cases, demonstrating that a BAL-driven antimicrobial treatment allows improvement of clinical outcome and survival.

Patients immunodéprimés, quel pathogène pour quel déficit immunitaire ? (en dehors de l’infection à VIH)

Le nombre de patients immunodéprimés ne cesse d’augmenter en raison de l’amélioration du pronostic global du cancer et de l’utilisation croissante d’immunosuppresseurs tant en transplantation qu’au cours des maladies auto-immunes. Les infections sévères restent la première cause d’admission en réanimation dans cette population et sont dominées par les atteintes respiratoires. On distingue les déficits primitifs, volontiers révélés dans l’enfance, des déficits secondaires (médicamenteux ou non), les plus fréquents. Dans tous les cas, les sujets sont exposés à des infections inhabituelles de par leur fréquence, leur type et leur sévérité. À côté des pyogènes habituels, les infections opportunistes et la réactivation d’infections latentes font toute la complexité de la démarche diagnostique. Celle-ci doit être rigoureuse, orientée par le type de déficit, les antécédents, les prophylaxies éventuelles et la présentation clinicoradiologique. Elle permettra seule de guider le traitement probabiliste et les examens étiologiques, l’absence de diagnostic étant associée à une mortalité élevée.

[Infections in immunocompromised patients (II). The transplanted patient]

Los receptores de los diferentes tipos de trasplante presentan un riesgo elevado de infección. En los trasplantados de precursores hematopoyéticos predominan las infecciones nosocomiales. Durante el periodo posprendimiento temprano (30-100 días tras la infusión del trasplante), la incidencia de infección es más elevada en pacientes con enfermedad de injerto contra huésped. En el pulmón pueden aparecer lesiones nodulares por infección fúngica invasora o bien un patón difuso habitualmente secundario a infección vírica o a neumonía por P. jirovecii. Después de los primeros 100 días persiste un moderado riesgo de infección por microorganismos convencionales y oportunistas, como la infección tardía por CMV. Los avances en las técnicas quirúrgicas y el empleo de calcineurínicos han reducido la mortalidad por infecciones en trasplantados de órgano sólido. Durante el primer mes, son frecuentes las infecciones nosocomiales; entre el primer y sexto mes son más frecuentes las infecciones oportunistas dependientes de la inmunidad celular y a partir de sexto mes el riesgo baja y predominan las infecciones comunitarias semejantes a las de los pacientes inmunocompetentes.

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.

Microbiologic Diagnostic Workup of Acute Respiratory Failure with Pulmonary Infiltrates after Allogeneic Hematopoietic Stem Cell Transplantation: Findings in the Era of Molecular- and Biomarker-Based Assays

Allogeneic hematopoietic stem cell transplantation (HSCT) recipients frequently develop acute respiratory failure (ARF) with pulmonary infiltrates. Molecular- and biomarker-based assays enhance pathogen detection, but data on their yield in this population are scarce. This was a retrospective single-center study of 156 consecutive HSCT recipients admitted to the intensive care unit (ICU) between May 2013 and July 2017. Findings from a microbiologic diagnostic workup using currently available methods on bronchoalveolar lavage (BAL) and blood samples from 66 patients (age, 58 years [range, 45 to 64]; HSCT to ICU, 176 days [range, 85 to 407]) with ARF and pulmonary infiltrates were analyzed. In 47 patients (71%) a causative pathogen was identified (fungal, n = 28; viral, n = 26; bacterial, n = 18). Polymicrobial findings involving several pathogen groups occurred in 20 patients (30%). Culture (12/16, 75%), galactomannan (13/15, 87%), and Aspergillus-PCR (8/9, 89%) from BAL but not serum galactomannan (6/14, 43%) helped to diagnose invasive aspergillosis (n = 16, 24%). Aspergillus-PCR detected azole resistance in 2 cases. Mucorales was found in 7 patients (11%; BAL culture, n = 6; Mucorales-PCR, n = 1). Patients with identified pathogens had higher Simplified Acute Physiology Score II scores (P = .049) and inferior ICU survival (6% versus 37%, P < .01), which largely related to the presence of an invasive fungal infection. Eight patients (12%) had 1 or more viruses with uncertain lung pathogenicity as the sole microbiologic finding. A diagnostic microbiologic workup incorporating molecular- and biomarker-based assays identified pathogens in most HSCT recipients with ARF and pulmonary infiltrates admitted to the ICU. Implications of polymicrobial infection and pathogen patterns in these patients warrant further investigation.

Pulmonary Infection in a Patient After Stem Cell Transplantation

A 69-year-old man with a history of hypertension, diabetes mellitus, and acute myelogenous leukemia presented with recurrent fever and cough. He had undergone allogeneic hematopoietic stem cell transplantation from a matched unrelated donor 17 months previously. His posttransplant course was complicated by graft versus host disease and multiple central venous catheter infections with coagulase-negative Staphylococcus spp., vancomycin-resistant Enterococcus, Lactobacillus, and alpha-hemolytic Streptococcus. During his initial course, he also developed a nodular pneumonia, and the subsequent workup included a bronchoscopy that was nondiagnostic.

Diagnostic Evaluation of Pulmonary Abnormalities in Patients with Hematologic Malignancies and Hematopoietic Cell Transplantation

Pulmonary complications (PC) of hematologic malignancies and their treatments are common causes of morbidity and mortality. Early diagnosis is challenging due to host risk factors, clinical instability, and provider preference. Delayed diagnosis impairs targeted treatment and may contribute to poor outcomes. An integrated understanding of clinical risk and radiographic patterns informs a timely approach to diagnosis and treatment. There is little prospective evidence guiding optimal modality and timing of minimally invasive lung sampling; however, a low threshold for diagnostic bronchoscopy during the first 24 to 72 hours after presentation should be a guiding principle in high-risk patients.

Utility of bronchoscopy in the definitive diagnosis of patients with haematological malignancies presenting with radiological abnormalities

INTRODUCTION

Patients with haematological malignancies usually have a plethora of respiratory complications. Bronchoscopy is one of the most important procedures used to diagnose respiratory complications. Despite enormous benefit, patients should be carefully selected for bronchoscopy as the process is invasive; however, there are only few reports evaluating the contributing factors of bronchoscopy that result in the definitive diagnosis of respiratory complications in these patients.

OBJECTIVE

This study aimed to elucidate and identify the contributing factors of bronchoscopy for definitive diagnosis in patients with haematological malignancies.

METHODS

We retrospectively analysed 275 patients with haematological malignancies who later showed respiratory complications, requiring consultation with pulmonologists. We found that 62 patients underwent bronchoscopy. Our data analysis focused on this particular subset of patients to identify the factors crucial for definitive diagnosis via bronchoscopy.

RESULTS

Bronchoscopy provided definitive diagnosis for 25 patients (diagnostic yield = 40.3%). We determined that nodular shadow was associated with high diagnostic yields by multivariate logistic regression [odds ratio (OR): 6.6 (2.1-23)]. Furthermore, in several bronchoscopic procedures, biopsy also contributed to definitive diagnosis of patients with nodular shadow [OR: 17 (1.5-180)]. Life-threatening complications were not observed due to bronchoscopy in our study.

CONCLUSIONS

Our study demonstrated that patients with haematological malignancies who showed lung nodular shadows are more likely to be definitively diagnosed by bronchoscopy, whereas transbronchial biopsy may also be beneficial for these patients.

An Unusual Cause of Pulmonary Nodules After Stem Cell Transplantation

A man in his 20s with a history of classical Hodgkin's lymphoma was admitted with fever. His original lymphoma diagnosis was made 3 years prior, when he had presented with lymphadenopathy and a mediastinal mass. He had relapsed disease despite chemotherapy and radiation. As a result, he underwent autologous peripheral blood stem cell transplant (SCT) 6 months prior to current presentation and subsequently allogeneic SCT 2 months prior for added graft vs tumor effect.

A Woman in Her 30s With a Past History of HIV Disease Presented With Recurrent Fever, Night Sweats, and Small Bilateral Pulmonary Nodules

A woman in her 30s presented with recurrent low-grade fever and cough (onset, 1 week). She reported occasional night sweats and weight loss of approximately 20 pounds over the past 4 months. She denied nausea, vomiting, diarrhea, or any urinary complaints. Her past medical history was significant for chronic hepatitis C and HIV infection, the latter diagnosed in 2001. She was noncompliant with highly active antiretroviral therapy for more than 4 years and had pneumocystis pneumonia 2 years prior to this presentation. She had a 10-pack per year smoking history and reported active use of cocaine and heroin. The patient denied any occupational exposures.

A 61-year-old male with generalised lymphadenopathy presenting with shortness of breath and infiltrates on chest radiography

A 61-year-old man presented for evaluation of a 6-week history of dyspnoea on exertion that had worsened over the past week. He denied having any recent illness, fevers, night sweats, nausea, vomiting, cough, chest pain, palpitations, or leg or back pain. He was diagnosed with chronic lymphocytic leukaemia (CLL) 5 years previously and had never been on chemotherapy.

Can you diagnose this 61-year-old male with generalised lymphadenopathy, dyspnoea and radiographic infiltrates?http://ow.ly/AXDg306hfqo

Usefulness of bronchoalveolar lavage and flow cytometry in patients with hematological malignancies and respiratory failure

BACKGROUND AND OBJECTIVES

Strategies to improve the efficiency of bronchoalveolar lavage (BAL) are needed. We conducted a study to establish the diagnostic value of BAL in patients with hematological malignancies and pulmonary infiltrates.

PATIENTS AND METHODS

The correlation of cytologic and flow cytometric study of BAL with the microbiological findings and the clinical evolution was determined.

RESULTS

Seventy BAL were performed and flow cytometric study was analyzed in 23 of them. Fifty-three patients did not present any adverse event attributable to BAL. Anti-infectious therapy was modified in 64 (91%) patients. T lymphocyte count >0.3×10⁹/l in peripheral blood was associated with longer OS at 3 years (53 vs. 22%, p=.009). Higher CD4 (>20/μL) and CD8 (>35/μL) lymphocyte counts in the BAL were associated with a longer OS at 3 years: 82 vs. 21% (p=.030) and 80 vs. 23% (p=.059).

CONCLUSIONS

Our study confirms the clinical value of BAL for treatment decision making in patients with hematological malignancies and acute respiratory failure.

Pneumocystis Pneumonia Presenting as an Enlarging Solitary Pulmonary Nodule

Pneumocystis pneumonia is a life threatening infection that usually presents with diffuse bilateral ground-glass infiltrates in immunocompromised patients. We report a case of a single nodular granulomatous Pneumocystis pneumonia in a male with diffuse large B-cell lymphoma after R-CHOP therapy. He presented with symptoms of productive cough, dyspnea, and right-sided pleuritic chest pain that failed to resolve despite treatment with multiple antibiotics. Chest X-ray revealed right lower lobe atelectasis and CT of chest showed development of 2 cm nodular opacity with ground-glass opacities. Patient underwent bronchoscopy and biopsy that revealed granulomatous inflammation in a background of organizing pneumonia pattern with negative cultures. Respiratory symptoms resolved but the solitary nodular opacity increased in size prompting a surgical wedge resection which revealed granulomatous Pneumocystis pneumonia infection. This case is the third documented report of Pneumocystis pneumonia infection within a solitary pulmonary nodule in an individual with hematologic neoplasm. Although Pneumocystis pneumonia most commonly occurs in patients with HIV/acquired immunodeficiency syndrome and with diffuse infiltrates, the diagnosis should not be overlooked when only a solitary nodule is present.

Critically ill allogeneic hematopoietic stem cell transplantation patients in the intensive care unit: reappraisal of actual prognosis

The outcome of allogeneic hematopoietic stem cell transplantation (allo-HSCT) patients has significantly improved over the past decade. Still, a significant number of patients require intensive care unit (ICU) management because of life-threatening complications. Literature from the 1990s reported extremely poor prognosis for critically ill allo-HSCT patients requiring ICU management. Recent data justify the use of ICU resources in hematologic patients. Yet, allo-HSCT remains an independent variable associated with mortality. However, outcomes in allo-HSCT patients have improved over time and many classic determinants of mortality have become irrelevant. The main actual prognostic factors are the need for mechanical ventilation, the presence of GvHD and the number of organ failures at ICU admission. Recently, the development of reduced-intensity conditioning regimens, early ICU admission and the increased use of noninvasive ventilation, combined with time effect and general advances in hematology, in allo-HSCT procedures and in ICU management have contributed to improve general outcome. A rational policy of ICU admission triage in these patients is very hard to define, as each decision for ICU admission is a case-by-case decision at patient bedside. The collaboration between hematologists and intensivists is crucial in this context.

Hematologic neoplasms: Interpreting lung findings in chest computed tomography

Lung disease is very common in patients with hematologic neoplasms and varies in function of the underlying disease and its treatment. Lung involvement is associated with high morbidity and mortality, so it requires early appropriate treatment. Chest computed tomography (CT) and the analysis of biologic specimens are the first line diagnostic tools in these patients, and sometimes invasive methods are necessary. Interpreting the images requires an analysis of the clinical context, which is often complex. Starting from the knowledge about the differential diagnosis of lung findings that radiologists acquire during training, this article aims to explain the key clinical and radiological aspects that make it possible to orient the diagnosis correctly and to understand the current role of CT in the treatment strategy for this group of patients.

Hematologic neoplasms: interpreting lung findings in chest computed tomography

La patología pulmonar en la historia de un paciente con neoplasia hematológica es muy frecuente y variable en función de la enfermedad de base y la terapia recibida. La morbimortalidad asociada es alta, por lo que requiere un tratamiento correcto y precoz. La tomografía computarizada (TC) torácica, junto con el análisis de muestras biológicas, son las herramientas de diagnóstico de primera línea empleadas en estos pacientes, y en determinados casos se requieren métodos invasivos. La interpretación de las imágenes exige el análisis de un contexto clínico en muchas ocasiones complejo. Partiendo del conocimiento que adquiere el radiólogo en su formación sobre el diagnóstico diferencial de los hallazgos pulmonares, el objetivo de este trabajo es explicar los aspectos clínicos y radiológicos claves que permiten orientar correctamente el diagnóstico y asimilar el papel actual de la TC en la estrategia terapéutica de este grupo de enfermos.

Infections Caused by Mycobacterium tuberculosis in Recipients of Hematopoietic Stem Cell Transplantation

Mycobacterium tuberculosis (M. tuberculosis) infections are uncommon in recipients of hematopoietic stem cell transplantation. These infections are 10-40 times commoner in recipients of stem cell transplantation than in the general population but they are 10 times less in stem cell transplantation recipients compared to solid organ transplant recipients. The incidence of M. tuberculosis infections in recipients of allogeneic stem cell transplantation ranges between <1 and 16% and varies considerably according to the type of transplant and the geographical location. Approximately 80% of M. tuberculosis infections in stem cell transplant recipients have been reported in patients receiving allografts. Several risk factors predispose to M. tuberculosis infections in recipients of hematopoietic stem cell transplantation and these are related to the underlying medical condition and its treatment, the pre-transplant conditioning therapies in addition to the transplant procedure and its own complications. These infections can develop as early as day 11 and as late as day 3337 post-transplant. The course may become rapidly progressive and the patient may develop life-threatening complications. The diagnosis of M. tuberculosis infections in stem cell transplant recipients is usually made on clinical grounds, cultures obtained from clinical specimens, tissues biopsies in addition to serology and molecular tests. Unfortunately, a definitive diagnosis of M. tuberculosis infections in these patients may occasionally be difficult to be established. However, M. tuberculosis infections in transplant recipients usually respond well to treatment with anti-tuberculosis agents provided the diagnosis is made early. A high index of suspicion should be maintained in recipients of stem cell transplantation living in endemic areas and presenting with compatible clinical and radiological manifestations. High mortality rates are associated with infections caused by multidrug-resistant strains, miliary or disseminated infections, and delayed initiation of therapy. In recipients of hematopoietic stem cell transplantation, isoniazid prophylaxis has specific indications and bacillus Calmette-Guerin vaccination is contraindicated as it may lead to disseminated infection. The finding that M. tuberculosis may maintain long-term intracellular viability in human bone marrow-derived mesenchymal stem cells complicates the development of effective vaccines and strategies to eliminate tuberculosis. However, the introduction of linezolid, cellular immunotherapy, and immunomodulation in addition to autologous mesenchymal stem cell transplantation will ultimately have a positive impact on the overall management of infections caused by M. tuberculosis.

Infections Caused by Stenotrophomonas maltophilia in Recipients of Hematopoietic Stem Cell Transplantation

Stenotrophomonas maltophilia (S. maltophilia) is a globally emerging Gram-negative bacillus that is widely spread in environment and hospital equipment. Recently, the incidence of infections caused by this organism has increased, particularly in patients with hematological malignancy and in recipients of hematopoietic stem cell transplantation (HSCT) having neutropenia, mucositis, diarrhea, central venous catheters or graft versus host disease and receiving intensive cytotoxic chemotherapy, immunosuppressive therapy, or broad-spectrum antibiotics. The spectrum of infections in HSCT recipients includes pneumonia, urinary tract and surgical site infection, peritonitis, bacteremia, septic shock, and infection of indwelling medical devices. The organism exhibits intrinsic resistance to many classes of antibiotics including carbapenems, aminoglycosides, most of the third-generation cephalosporins, and other β-lactams. Despite the increasingly reported drug resistance, trimethoprim-sulfamethoxazole is still the drug of choice. However, the organism is still susceptible to ticarcillin-clavulanic acid, tigecycline, fluoroquinolones, polymyxin-B, and rifampicin. Genetic factors play a significant role not only in evolution of drug resistance but also in virulence of the organism. The outcome of patients having S. maltophilia infections can be improved by: using various combinations of novel therapeutic agents and aerosolized aminoglycosides or colistin, prompt administration of in vitro active antibiotics, removal of possible sources of infection such as infected indwelling intravascular catheters, and application of strict infection control measures.

Adenovirus pneumonia presenting with nodular shadows on chest X-ray in two unrelated allogeneic bone marrow transplant recipients

Adenoviruses are increasingly recognized as important pathogens following allogeneic stem cell transplantation. We herein report two cases of disseminated adenovirus infection that presented with nodular shadows on chest X-ray after allogeneic bone marrow transplantation from unrelated donors. Both patients died of respiratory failure. Autopsies revealed adenovirus infection of multiple organs. Adenovirus infection should be suspected when nodular lung lesions of unknown origin appear in allogeneic stem cell transplant recipients.

Rational approach to pulmonary infiltrates in leukemia and transplantation

At present, a number of invasive diagnostic techniques can be used to diagnose the cause of lung infiltrates in patients with hematologic malignancies or hematopoietic stem cell transplantation recipients. Bronchoscopy with measurement of biomarkers in the bronchoalveolar lavage (BAL) will most likely become the preferred method to diagnose infectious causes of pulmonary infiltrates. However, there is no uniform approach regarding the technical parameters of the lavage procedure in cancer patients. Diagnostic protocols vary by region, center, and the expertise of the staff. This mini review discusses the issues surrounding diffuse pulmonary infiltrates and provides some recommendations to deal with these issues.

The pulmonologist's point of view on lung infiltrates in haematological malignancies

In haematological malignancies, the development of lung disease is a common source of significant morbidity and mortality for this population of patients. There is a wide range of infectious and non-infectious aetiologies that can be responsible for such complications. It is a major challenge to make an early diagnosis of aetiology in order to choose the most suitable treatment. Computed tomography (CT) of the chest has undeniably become a crucial tool in diagnosing these cases of lung disease. Although it is not possible to make a definitive diagnosis of aetiology based solely on analysing CT scan findings in these complex patients, there are some abnormalities that are highly suspicious for particular diagnoses. CT, therefore, allows the clinician to put forward and prioritise possible diagnoses that may then be considered in view of clinical information and laboratory study results. There must be multidisciplinary involvement in the management of lung disease patients and there must be an ongoing dialogue between the radiologist and the clinician.

Have novel serum markers supplanted tissue diagnosis for invasive fungal infections in acute leukemia and transplantation?

Invasive fungal infections (IFIs) are difficult to diagnose, especially early in the course of infection when antifungal therapy is most effective. There are two commercially available biomarker assays useful for detection of the IFIs most commonly seen in patients with hematologic malignancies, the galactomannan and beta glucan assays. The former is specific for aspergillosis, the latter positive for not only Aspergillus and Candida species, but several other clinically relevant fungal pathogens as well. Both have good assay performance characteristics, provide rapid test results, are widely available, can be assayed non-invasively, and are positive early in the course of infection, often before onset of signs and symptoms of infection. Adoption of these assays into clinical practice has led to reduced need to perform invasive procedures to obtain deep tissue to establish the diagnosis of invasive fungal infections. Improved survival rates from aspergillosis are, in part, due to earlier detection of infection and earlier therapy.