Acute respiratory failure caused by secondary alveolar proteinosis in a patient with acute myeloid leukemia: a case report

Chronic myelomonocytic leukemia-associated pulmonary alveolar proteinosis: A case report and review of literature

BACKGROUND

Pulmonary alveolar proteinosis (PAP) is a rare condition that can cause progressive symptoms including dyspnea, cough and respiratory insufficiency. Secondary PAP is generally associated with hematological malignancies including chronic myelomonocytic leukemia (CMML). To the best of our knowledge, this is the first reported case of PAP occurring secondary to CMML.

CASE SUMMARY

We report the case of a 63-year-old male who presented with a recurrent cough and gradually progressive dyspnea in the absence of fever. Based upon clinical symptoms, computed tomography findings, bone marrow aspiration, flow cytometry studies and cytogenetic analyses, the patient was diagnosed with PAP secondary to CMML. He underwent whole lung lavage in March 2016 to alleviate his dyspnea, after which he began combined chemotherapeutic treatment with decitabine and cytarabine. The patient died in January 2020 as a consequence of severe pulmonary infection.

CONCLUSION

This case offers insight regarding the mechanistic basis for PAP secondary to CMML and highlights potential risk factors.

Plugs of the Air Passages: A Clinicopathologic Review

Although mucus is a normal product of the tracheobronchial tree, some diseases of the respiratory tract are characterized by unusually thick (inspissated) forms of mucus that accumulate within the airways. These are known as mucus plugs. The pathologic composition of these plugs is surprisingly diverse and, in many cases, correlates with distinctive clinical, radiologic, and bronchoscopic findings. The best-known conditions that involve mucus plugs are allergic bronchopulmonary aspergillosis, plastic bronchitis, and asthma. Other lung diseases occasionally associated with plugs within the airways include Aspergillus tracheobronchitis, hyper-IgE syndrome, exogenous lipoid pneumonia, pulmonary alveolar proteinosis, and chronic eosinophilic pneumonia. In this review, we describe and illustrate the bronchoscopic, pathologic, and imaging findings in respiratory disorders characterized by mucus plugs or plugs composed of other similar materials. Recognition of the characteristic appearance and differential diagnosis of mucus plugs will hopefully facilitate diagnosis and management of these diseases.

Rare Presentation of Pulmonary Alveolar Proteinosis Causing Acute Respiratory Failure

Pulmonary alveolar proteinosis (PAP) is a rare condition characterized by dysfunctional alveolar macrophages, which ineffectively clear surfactant and typically cause mild hypoxemia. Characteristic Computed Tomography findings are septal reticulations superimposed on ground-glass opacities in a crazy paving pattern, with a clear juxtaposition between affected and unaffected parenchyma. While traditionally PAP was diagnosed via biopsy, bronchoalveolar lavage (BAL) is usually sufficient; the fluid appears milky, and on microscopic examination there are foamy macrophages with eosinophilic granules and extracellular hyaline material that is Periodic Acid-Schiff positive. Standard therapy is whole lung lavage (WLL), although novel treatments are under development. The case presented is a 55-year-old woman with six months of progressive dyspnea, who developed hypoxemic respiratory failure requiring mechanical ventilation; she had typical findings of PAP on imaging and BAL. WLL was ultimately successful in restoring adequate oxygenation. Respiratory failure of this magnitude is a rare finding in PAP.

Pulmonary alveolar proteinosis and superinfection with pulmonary tuberculosis in a case

Pulmonary alveolar proteinosis (PAP) is a rare and diffuse lung process, characterized by the presence of alveolar spaces filled with amorphous eosinophilic material. Impaired macrophage function and impaired host defence due to abnormalities of surfactant proteins may favor the growth of microorganisms. The association of alveolar proteinosis with mycobacterial infections is rarely reported. The PAP and superinfection with pulmonary tuberculosis is defined by radiologic and histopathologic in a 46 year-old patient. The patients with PAP should be monitored for superinfection. It may cause the disease progression and radiological, clinical symptoms may improve with treatment of superinfection.

Secondary pulmonary alveolar proteinosis: a confusing and potentially serious complication of hematologic malignancy

OBJECTIVE

We analyzed the computed tomography and clinical findings of pulmonary alveolar proteinosis secondary to hematologic malignancy.

MATERIALS AND METHODS

Seven patients with hematologic malignancy and pathologically proven secondary pulmonary alveolar proteinosis were identified from 2000 to 2007. Six had chest computed tomography scans, which were analyzed retrospectively; medical records were also reviewed.

RESULTS

Patient age ranged from 30 to 54 years. Four had chronic myelogenous leukemia, 1 had myelodysplastic syndrome, and 1 had cutaneous T-cell lymphoma. As in idiopathic pulmonary alveolar proteinosis, geographic ground-glass opacities with or without septal thickening were most common (5/6). No axial or zonal predominance was present. Two patients died from respiratory failure.

CONCLUSIONS

It is important to consider secondary pulmonary alveolar proteinosis as a cause of geographic ground-glass opacities and septal thickening in a patient with hematologic malignancy. Whereas idiopathic pulmonary alveolar proteinosis has a low mortality rate, the death of 2 of our 6 patients implies that secondary pulmonary alveolar proteinosis may have a worse prognosis. Our case of secondary pulmonary alveolar proteinosis associated with cutaneous T-cell lymphoma is the first described in the literature.

Update in nonneoplastic lung diseases

CONTEXT

Nonneoplastic lung diseases include a wide range of pathologic disorders from asthma to interstitial lung disease to pulmonary hypertension. Recent advances in our understanding of the pathophysiology of many of these disorders may ultimately impact diagnosis, therapy, and prognosis. It is important for the practicing pathologist to be aware of this new information and to understand how it impacts the diagnosis, treatment, and outcome of these diseases.

OBJECTIVE

To update current progress toward elucidating the pathophysiology of pulmonary alveolar proteinosis, idiopathic pulmonary hemosiderosis, and pulmonary arterial hypertension, as well as to present classification systems for pulmonary hypertension, asthma, and interstitial lung disease and describe how these advances relate to the current practice of pulmonary pathology.

DATA SOURCES

Published literature from PubMed (National Library of Medicine) and primary material from the authors' institution.

CONCLUSIONS

Improved understanding of the pathophysiology of pulmonary alveolar proteinosis, pulmonary hypertension, and idiopathic hemosiderosis may impact the role of the surgical pathologist. New markers of disease may need to be assessed by immunohistochemistry or molecular techniques. The classification systems for interstitial lung disease, asthma, and pulmonary hypertension are evolving, and surgical pathologists should consider the clinicopathologic context of their diagnoses of these entities.

High titer autoantibodies to GM-CSF in patients with AML, CML and MDS are associated with active disease

Antibodies to granulocyte-macrophage colony-stimulating factor (GM-CSF) can be induced when GM-CSF is used as an adjuvant to solid tumor vaccination. Neutralizing anti-GM-CSF IgG has been associated with pulmonary alveolar proteinosis (PAP), and secondary PAP has been linked to myeloid leukemia. We studied 69 patients with acute myeloid leukemia, chronic myeloid leukemia and myelodysplastic syndrome, including 19 patients who received GM-CSF with peptide antigen and incomplete Freund's adjuvant in a vaccine trial for the presence or induction of anti-GM-CSF antibodies. Anti-GM-CSF IgG were present in 36 (52%) patients with myeloid leukemia compared to only 1 of 33 (3%) healthy subjects (P=0.008) and in none of 6 patients with lymphoid leukemia (P=0.0001). Antibody titers were unaffected by vaccination. Anti-GM-CSF IgA and IgM were found in 33 and 20% of patients, respectively; IgA from two patients neutralized GM-CSF. Strikingly, while anti-GM-CSF IgG titers were higher in patients with active disease (n=52) versus those in complete remission (n=14, P=0.0009), GM-CSF expression was not increased in either group. These data are first to show that anti-GM-CSF antibodies of multiple isotypes are present in patients with active myeloid leukemia without PAP and may be useful markers of disease activity.

Pulmonary alveolar proteinosis

Pulmonary alveolar proteinosis is a rare syndrome characterized by intra-alveolar accumulation of surfactant components and cellular debris, with minimal interstitial inflammation or fibrosis. The condition has a variable clinical course, from spontaneous resolution to respiratory failure and death due to disease progression or superimposed infections. The standard of care for alveolor proteinosis therapy is represented by whole lung lavage. Important discoveries have been made in the last decade with respect to disease pathogenesis and therapy of both congenital and acquired forms of the disease. Granulocyte-macrophage colony-stimulating factor (GM-CSF) pathway has been shown to be involved in the disease pathogenesis of both acquired and congenital disease. Furthermore, anti-GM-CSF blocking autoantibodies have been found in the serum and bronchoalveolar lavage fluid and seem to interfere with the surfactant clearance by alveolar macrophages in many acquired cases. In the congenital form, the most common defects identified to date are several mutations of the genes encoding GM-CSF receptor subunits or surfactant proteins. Using GM-CSF as a therapeutic tool has also been shown to be effective in at least half of the acquired cases treated, while the importance of quantitative determination of anti-GM-CSF antibodies before and during the course of the therapy, as well as the autoantibody titer-GM-CSF dose relationship are to be elucidated. The congenital form of the disease does not respond to therapy with GM-CSF, consistent with the known primary defects and differences in disease pathogenesis.

[Pulmonary alveolar phospholipoproteinosis]

Pulmonary alveolar phospholipoproteinosis is a rare lung disease of unknown cause characterized by surfactant plugging of the alveoli. At the present time, surgical lung biopsy, long considered as the gold standard, is not necessary for positive diagnosis of pulmonary alveolar phospholipoproteinosis when computed tomography anomalies and analysis of bronchial lavage fluids present a typical pattern. Treatment requires abundant lavage, but the demonstration of anti-GM-CSF antibodies in primary forms opens new therapeutic perspectives.

Pulmonary Alveolar Proteinosis

Pulmonary alveolar proteinosis (PAP) is characterized by the accumulation of surfactant phospholipids and proteins within the lung alveoli. Important advances have been made over the past 8 years in our understanding of this disease, offering new directions for research and patient care. First, genetically altered mice that are homozygous for a disrupted granulocyte-macrophage colony-stimulating factor (GM-CSF) gene developed a lung lesion with histologic resemblance to PAP. The surfactant is thought to be catabolized or cleared mostly by alveolar macrophages, this process being dependent on GM-CSF. Second, a neutralizing autoantibody against GM-CSF was found in serum and bronchoalveolar lavage fluid of patients with idiopathic PAP but not in healthy controls, thereby raising the suspicion that human PAP may be an autoimmune disease. The relationship between the antibody and disease pathogenesis remains unclear but data suggest that the GM-CSF antibody may have a potential role as a diagnostic test. No specific therapy exists for PAP. Sequential whole lung lavage is the standard of care. Exogenous therapy with GM-CSF may improve the lung disease in some patients with PAP but this therapy is still experimental. Interventions directed at treating a relative GM-CSF deficiency by administration of GM-CSF or lowering the antibody level (i.e. by plasmapheresis or immunosuppression) may hold promise as future therapy for this rare disease.

Pulmonary alveolar proteinosis in a patient with acute lymphoid leukemia regression after G-CSF therapy

Pulmonary alveolar proteinosis (PAP) is the intra-alveolar accumulation of periodic-acid schiff (PAS) positive material. PAP is one of the underrecognized causes of pulmonary infiltrates in patients with hematologic malignancies. Here, we present a patient with acute lymphoid leukemia (ALL) in first remission that developed fever and diffuse pulmonary infiltrates during the neutropenic stage of consolidation chemotherapy. The histopathologic examination of bronchoalveolar lavage (BAL) fluid and transbronchial biopsy specimen demonstrated the presence of PAS-positive eosinophilic material. Empirical antibiotherapy and granulocyte-colony stimulating factor (G-CSF) were given. After the correction of neutropenia with G-CSF, the patient's fever disappeared, acute phase reactants decreased, pulmonary infiltrates resolved. We present this case because it was the first patient in whom the correction of neutropenia with G-CSF was followed by resolution of PAP.

Radiographic approach to multifocal consolidation

Consolidation in the lung is seen on radiographs or computed tomography (CT) as increased areas of attenuation that obscure the underlying pulmonary vasculature. There are numerous causes of multifocal consolidative opacities. If the symptoms are acute (days to weeks), the most common causes include edema, pneumonia, and hemorrhage. Depending on the patient's history, signs, and symptoms, the less common causes such as radiation pneumonitis or acute eosinophilic syndrome may be considered. If the symptoms are more chronic (weeks to months), the differential may include alveolar proteinosis, neoplasms such as lymphoma or bronchoalveolar cell carcinoma, granulomatous or inflammatory conditions, and lipoid pneumonia. In this article, we review and discuss characteristic radiographic and clinical findings that can aid the radiologist in prioritizing the differential considerations when faced with multifocal parenchymal consolidative disease.

Approach to ground-glass opacification of the lung

There area number of diseases that present with ground-glass opacification of the lung as a primary manifestation on chest radiography and thin-section computed tomography (CT). These diseases cannot be clearly categorized into the classic classification scheme of airspace and interstitial disease because there are features of both categories seen in the imaging and histologic findings. Ground-glass opacification has, therefore, been categorized as nonspecific by many radiologists. The fact that both the airspaces and interstitial tissues are often involved should have little importance when evaluating radiographs or high-resolution CT (HRCT) images. The role of the radiologist is evolving and is becoming more significant in the clinical evaluation of a patient presenting with so-called interstitial lung disease. In this article, an approach is described that hopefully will lead to an effective and narrow differential diagnosis when a radiologist is confronted with ground-glass opacification. The critical features in evaluating such cases include: (1) the duration of clinical symptoms; (2) the presence or absence of lung fibrosis, especially honeycombing; (3) the patient's history of smoking; and (4) the distribution of the disease. Each of these features is considered in this article in conjunction with the diseases that lead to ground-glass opacification. The recent thinking regarding nonspecific interstitial pneumonia and usual interstitial pneumonia also is discussed.

Diffuse lung disease in the immunocompromised non-HIV patient

Physicians are encountering an increasing number of patients with various levels of immunosuppression, such as patients with AIDS, transplant recipients, patients on immunosuppressive therapy, and those with congenital immune defects and malignancy. This results in a greater diagnostic dilemma for the medical community because of the significant increased risk of opportunistic infections and noninfectious complications, as well as a more aggressive clinical course with typical pathogens. [figure: see text] Furthermore, it is not just the pathogens that are changing but also their clinical and radiographic presentations. The radiologist has a large role in not only detecting the presence of disease but also in narrowing the differential possibilities. This can be an overwhelming task given the wide variety of presentations of diseases on radiographs. However, by understanding the level and degree of the patient's immunosuppression, the radiologist may anticipate the most likely pulmonary complications. By using the radiographic morphology, distribution, and temporal evolution of the abnormalities, a manageable differential diagnosis can be created for referring clinicians.

Severe alveolar proteinosis following chemotherapy for acute myeloid leukemia in a lung allograft recipient

A 64-year-old man was diagnosed with acute myeloid leukemia (AML) 5 years following single lung transplantation performed for severe pulmonary hypertension from scleroderma. Chemotherapy for treatment of AML with fludarabine, cytosine arabinoside, G-CSF (FLAG) regimen was initiated. Despite intensive antibiotic treatment for a presumptive diagnosis of bacterial pneumonia, the patient developed acute respiratory failure and died before a complete cycle of chemotherapy could be administered. At autopsy, both native and allograft lungs showed widespread alveolar proteinosis that was determined as the main cause of acute respiratory failure. Alveolar proteinosis, a potentially treatable disease, should be considered in the radiologic differential diagnosis of diffuse lung disease in this clinical setting.