Autoimmune Pulmonary Alveolar Proteinosis Complicated with Sarcoidosis: the Clinical Course and Serum Levels of Anti-granulocyte-macrophage colony-stimulating Factor Autoantibody

Autoimmune pulmonary alveolar proteinosis (APAP) is caused by macrophage dysfunction due to anti-granulocyte-macrophage colony-stimulating factor (GM-CSF) autoantibody. We experienced 2 cases of APAP complicated with sarcoidosis in a 42-year-old woman and a 51-year-old man (age at the sarcoidosis diagnosis). APAP preceded sarcoidosis in the woman, and both diseases were diagnosed simultaneously in the man. Sarcoidosis lesions were observed in the lung, skin, and eyes, and the pathological findings of APAP were not marked at the diagnosis of sarcoidosis in either case. Low-grade positive serum anti-GM-CSF autoantibody was suspected to be correlated with the occurrence of sarcoidosis and resolution of APAP.

Assay system development to measure the concentration of sargramostim with high specificity in patients with autoimmune pulmonary alveolar proteinosis after single-dose inhalation

During a clinical trial of a Saccharomyces cerviciae-derived recombinant human granulocyte-macrophage colony stimulating factor (rhGM-CSF), sargramostim, in patients with autoimmune pulmonary alveolar proteinosis (aPAP), we conducted a pharmacokinetic study of single-dose sargramostim inhalation. Several problems were encountered whereby sargramostim formed an immune-complex with GM-CSF autoantibodies (GMAbs) immediately after entering the body; thus, we could not measure the concentration of sargramostim using a commercial high sensitivity enzyme-linked immunosorbent assay (ELISA). Moreover, the ELISA could not discriminate inhaled sargramostim from intrinsic GM-CSF. To solve these problems, we developed a novel ELISA system with a capture antibody that is specific for sargramostim and a detection antibody capable of binding with GM-CSF. This system quantified the serum sargramostim concentration, but not E. coli-, CHO-, or HEK293T-derived human recombinant GM-CSF. Using this system, serum pharmacokinetics were estimated in five patients after inhalation of 250 μg sargramostim, with a mean Cmax of 9.7 ± 2.85 pg/ml at a Tmax of 2 ± 1.22 h.

Surfactant protein B: From biochemistry to its potential role as diagnostic and prognostic marker in heart failure

Growing interest raised on circulating biomarkers of structural alveolar-capillary unit damage and very recent data support surfactant protein type B (SP-B) as the most promising candidate in this setting. With respect to other proteins proposed as possible markers of lung damage, SP-B has some unique qualities: it is critical for the assembly of pulmonary surfactant, making its lack incompatible with life; it has no other known site of synthesis except alveolar epithelial cells different from other surfactant proteins; and, it undergoes a proteolytic processing in a pulmonary-cell-specific manner. In the recent years circulating SP-B isoforms, mature or immature, have been demonstrated to be detectable in the circulation depending on the magnitude of the damage of alveolar capillary membrane. In the present review, we summarize the recent knowledge on SP-B regulation, function and we discuss its potential role as reliable biological marker of alveolar capillary membrane (dys)function in the context of heart failure.

MUC1 gene polymorphisms are associated with serum KL-6 levels and pulmonary dysfunction in pulmonary alveolar proteinosis

BACKGROUND

KL-6, a human MUC1 mucin, is a sensitive biomarker for interstitial lung diseases including pulmonary alveolar proteinosis (PAP). A correlation between MUC1 gene single nucleotide polymorphism (SNP) rs4072037 genotype and serum KL-6 levels has been reported. This study was aimed at investigating the correlation between MUC1 SNP genotype, severity of disease and disease outcome in PAP.

METHODS

Twenty four patients with PAP and 30 healthy volunteers were studied. MUC1 rs4072037 was detected by using a real-time polymerase chain reaction (RT-PCR). Genotyping was performed by pyrosequencing. KL-6 levels were measured in serum by Nanopia KL-6 assay (SEKISUI Diagnostics).

RESULTS

The frequency of MUC1 rs4072037 alleles was significantly different between PAP patients and healthy volunteers (PAP, A/A 46%, A/G 54%, G/G 0%; healthy controls, A/A 30%, A/G 40%, G/G 30%; p = 0.013). Serum KL-6 levels were significantly higher in PAP patients than in controls (p < 0.0001), and significantly higher in PAP patients with A/A genotype than in those with A/G genotype (p = 0.007). Patients with A/A genotype had higher alveolar-arterial oxygen difference (A-aDO2) and lower DLco compared to those with A/G genotype (p = 0.027 and p = 0.012, respectively). Multivariate analysis, Kaplan-Meier analysis and C statistics showed that the rs4072037 A/A genotype was associated with higher rate of disease progression (HR: 5.557, p = 0.014).

CONCLUSIONS

MUC1 rs4072037 A/A genotype is associated with more severe pulmonary dysfunction and a higher rate of disease progression in PAP patients.

[Serum markers in patients with idiopathic pulmonary alveolar proteinosis]

OBJECTIVE

Pulmonary alveolar proteinosis (PAP) is a rare lung disease characterized by PAS positive lipoproteinaceous material accumulation in the pulmonary alveoli, of which autoimmune (APAP) or idiopathic type (IPAP) accounts for about 90%. Several serum markers were reported to be valuable in IPAP diagnosis. However, data in Chinese patients was not available. Here we analyzed the diagnostic value of serum markers in Chinese IPAP patients.

METHODS

Thirty-one IPAP patients, 25 healthy volunteers and 15 patients with other lung diseases were enrolled in the study. Anti-GM-CSF antibody, SP-A, SP-D and YKL-40 levels of the serum samples were tested by ELISA method. LDH, CEA, arterial blood gas analysis and pulmonary function test results were collected and analyzed. Then the difference between the groups and the relationship between the 2 of the markers were tested.

RESULTS

The level of serum anti-GM-CSF antibody, SP-A and SP-D [29.80(13.02-53.86) mg/L, (47 ± 30) and (77 ± 57) µg/L respectively] were higher in IPAP patients than in healthy volunteers and disease control patients (P < 0.05). IPAP and disease control groups had higher YKL-40 and LDH levels than the healthy control group (P < 0.05), but no statistical difference between the former 2 groups (P > 0.05). The CEA level of IPAP patients was higher than that of the disease control group (P < 0.05). The sensitivity and specificity of anti-GM-CSF antibody in IPAP diagnosis were both 100% at the cut-off value of 2.46 µg/mL. The LDH, CEA and SP-A levels correlated positively with P(A-a) O₂ and negatively with TL(CO)%, PaO₂ and SaO₂ (P < 0.05). The SP-D level correlated negatively with SaO₂ (P < 0.05), and positively with LDH and CEA level (P < 0.05), so did SP-A (P < 0.05). YKL-40 correlated positively with SP-A but not with other markers. Anti-GM-CSF antibody did not correlate with any of the markers.

CONCLUSIONS

Serum anti-GM-CSF antibody testing showed high sensitivity and specificity for the diagnosis of APAP, though it did not correlate with disease severity. Serum LDH, CEA, SP-A and SP-D levels were elevated in IPAP patients and correlated well with disease severity. YKL-40 level was also higher in IPAP patients, but it could not be used as a disease severity marker.

Pulmonary alveolar proteinosis

The term pulmonary alveolar proteinosis (PAP) comprises a heterogeneous group of rare disorders characterized by abundant deposition of surfactant- and lipoproteins in the alveoli. The autoimmune form accounts for 90% of cases and is characterized by the presence of GM-CSF autoantibodies. Secondary PAP is associated with several underlying conditions, mainly hematologic malignancies, infections and inhalation exposure, and is GM-CSF antibody negative. Several conditions can mimic PAP, in particular the radiological findings: the crazy paving pattern on high resolution computed tomography (HRCT) is common also to infections, neoplasms, and other interstitial lung diseases. Bronchoalveolar lavage (BAL) typical findings and the detection of serum GM-CSF antibodies are usually sufficient for the diagnosis of PAP. Whole lung lavage (WLL) is still the gold standard for treatment of PAP and is followed by complete remission in about 50% of cases. Inhalative treatment with GM-CSF alone or in combination with WLL could represent the future approach for patients with autoimmune PAP refractory to WLL alone. The anti CD-20 antibody rituximab represents a further promising approach for autoimmune PAP. The treatment of secondary PAP should be focused on the underlying disease.

Impaired lipid metabolism in idiopathic pulmonary alveolar proteinosis

BACKGROUND

It is well known that lipids abnormally accumulate in the alveoli during idiopathic pulmonary alveolar proteinosis (PAP). It is unclear, however, whether lipids also abnormally accumulate in serum. This study investigated the serum lipid panels in idiopathic PAP patients and explored the relationships between serum levels and the severity of idiopathic PAP.

METHODS AND RESULTS

Clinical data including the level of serum lipids were evaluated in 33 non-diabetic idiopathic PAP patients and 157 healthy volunteers. Serum levels of triglyceride were higher in PAP patients than in healthy subjects (median: 192.00 mg/dl (P25: 104.36, P75: 219.00) vs 119.56 mg/dl (P25: 78.81, P75: 193.03), P < 0.05), while high-density lipoprotein cholesterol (HDL-C) levels were lower in patients than in the control group (42.50 ± 10.30 vs 51.34 ± 12.06 mg/dl, P < 0.01). Forced expiratory volume in one second and forced vital capacity in hypertriglyceridemia patients were lower than those in patients with normal triglyceride. Serum LDL-C and HDL-C ratio correlated negatively with PaO2 (r = -0.403, P < 0.05) and positively with lactate dehydrogenase (r = 0.381, P < 0.05).

CONCLUSIONS

PAP associates with high triglyceride and low HDL levels in the serum, and these lipids provide potential intervention strategy for treatment.

Clinical importance of bronchoalveolar lavage fluid and blood cytokines, surfactant protein D, and Kerbs von Lungren 6 antigen in idiopathic pulmonary alveolar proteinosis

OBJECTIVE

To investigate the clinical importance of cytokines, surfactant protein D (SFTPD, formerly SP-D), and Kerbs von Lungren 6 antigen (KL-6) in bronchoalveolar lavage fluid (BALF) and blood in patients with idiopathic pulmonary alveolar proteinosis (iPAP).

PARTICIPANTS AND METHODS

Patients with iPAP diagnosed by characteristic cytopathologic examination of BALF and pathologic examination of transbronchial lung biopsy specimens or open lung biopsy specimens were enrolled in the study from January 1, 1995, through June 30, 2005. To investigate the clinical importance of cytokines, SFTPD, and KL-6 in iPAP, we measured tumor necrosis factor superfamily, member 2 (TNF, formerly TNF-alpha) and interleukin (IL) 1beta in BALF and IL-6, IL-10, IL-8, chemokine (C-C motif) ligand 4 (CCL4, formerly MIP-1beta), chemokine (C-C motif) ligand 2 (CCL2, formerly MCP-1), SFTPD, and KL-6 in both BALF and blood in 15 patients with iPAP and 48 patients with interstitial lung diseases (diseased controls) (including 20 with interstitial pneumonitis associated with collagen vascular diseases, 13 with idiopathic pulmonary fibrosis, and 15 with sarcoidosis) and 20 individuals without pulmonary diseases (lung controls).

RESULTS

Patients with iPAP had significantly higher levels of TNF, IL-6, IL-8, CCL4, CCL2, SFTPD, and KL-6 in BALF than did lung controls and had significantly higher levels of CCL4, CCL2, SFTPD, and KL-6 levels in BALF than did diseased controls. Patients with iPAP had significantly higher levels of IL-10, IL-8, CCL2, SFTPD, and KL-6 in blood than did lung controls and significantly higher levels of KL-6 in blood than did diseased controls. Levels of KL-6 both in BALF and blood were significantly correlated with serum lactate dehydrogenase level, arterial oxygen tension, and alveolar-arterial gradient in partial pressure of oxygen, the severity markers for iPAP, and were significantly higher in patients with iPAP who required subsequent therapeutic lung lavage.

CONCLUSION

Patients with iPAP had elevated levels of SFTPD, KL-6, and cytokines in both BALF and blood. Elevated levels of KL-6 in both BALF and blood may be valuable in reflecting disease severity of patients with iPAP and in determining the need for therapeutic lung lavage.

Elevated BALF concentrations of α- and β-defensins in patients with pulmonary alveolar proteinosis

Defensins are endogenous antibiotics and regulators of inflammation, immunity and wound repair. Their concentrations are substantially increased in bronchoalveolar lavage fluid (BALF) of patients with infectious lung diseases. alpha-defensin (HAD) levels are also elevated in patients with idiopathic pulmonary fibrosis (IPF) and correlated with the decline in pulmonary function tests, suggesting the association of defensins with the pathogenesis of interstitial lung diseases. The aim of this study was to determine the profile of defensins in interstitial lung diseases. Serum and BALF levels of HAD and beta-defensin 1 and 2 (HBD-1, and -2) were measured by radioimmunoassay in 63 patients with interstitial lung diseases, including idiopathic pulmonary alveolar proteinosis (PAP), IPF, nonspecific interstitial pneumonia (NSIP), cryptogenic organizing pneumonia (COP) and pulmonary sarcoidosis, and in 9 healthy volunteers as controls. Levels of HAD in BALF of patients with PAP were significantly higher than those in controls and patients with COP and sarcoidosis. Serum levels of HAD in all groups were significantly higher than those in controls. Levels of HBD-1 and -2 in BALF of patients with PAP were extremely high in all subjects. Serum levels of HBD-1 were higher in all patient groups, with the exception of those with PAP, and those of HBD-2 were also higher in patients with IPF and sarcoidosis, compared with controls. BALF of PAP patients, but not IPF patients and controls, expressed antimicrobial activity against Pseudomonas aeruginosa and Staphylococcus aureus. Our findings suggest different kinetics of HAD and HBD-1 and -2 in serum and BALF of interstitial lung diseases and that these antimicrobial peptides in the airway lumen may contribute to prevention of bacterial airway infections in PAP.

Epidemiological and clinical features of idiopathic pulmonary alveolar proteinosis in Japan

Idiopathic pulmonary alveolar proteinosis (IPAP) is a rare disease characterized by excessive amounts of lipoproteinaceous material in the alveolus. This report presents an interim analysis of nationwide epidemiological data from Japanese patients with pulmonary alveolar proteinosis, and the roles of serum markers for IPAP. (i) The nationwide demographic data from 166 Japanese patients with IPAP are shown. The female to male ratio was 1:2, and the average age was 51 +/- 14 years old (age range: 15-79 years) at registration or diagnosis. A total of 30% of patients with IPAP have a poor clinical course. In total, 30% of patients were treated with whole lung lavage therapy (WLL). Under WLL, the patients significantly improved in the short term, but 40% of the patients who underwent WLL worsened again. A new strategy such as granulocyte-macrophage colony-stimulating factor (GM-CSF) therapy for intractable PAP is required. (ii) The correlation of serum KL-6, carcinoembryonic antigen, surfactant proteins D and A, and LDH with disease severity suggests their potential as disease markers. In contrast, serum anti-GM-CSF antibody did not correlate with disease severity, but is a specific marker for the diagnosis of IPAP. The combined measurements of the serum markers may well prove very useful for both the diagnosis and the management of IPAP patients.

Multiplexed particle-based anti-granulocyte macrophage colony stimulating factor assay used as pulmonary diagnostic test

Pulmonary alveolar proteinosis (PAP) is characterized by the accumulation of lipoproteinaceous material within the lung alveoli. Recent studies indicate that PAP is an autoimmune disease characterized by a neutralizing anti-granulocyte macrophage colony stimulating factor (GM-CSF) antibody. At present the only definitive diagnostic test for PAP is open lung biopsy. We have previously published that anti-GM-CSF is diagnostic for PAP and correlates with disease pathogenesis using a traditional serial anti-GM-CSF antibody titer format (T. L. Bonfield, M. S. Kavuru, and M. J. Thomassen, Clin. Immunol. 105:342-350, 2002). Titer analysis is a semiquantitative method, and often subtle changes in antibody titer are not detectable. In this report we present data to support anti-GM-CSF detection by a quantitative highly sensitive multiplexed particle-based assay which has the potential to be a clinical diagnostic test.

Relationship of anti-GM-CSF antibody concentration, surfactant protein A and B levels, and serum LDH to pulmonary parameters and response to GM-CSF therapy in patients with idiopathic alveolar proteinosis

BACKGROUND

Conventional measures of the severity of alveolar proteinosis (AP) include alveolar-arterial oxygen gradient ([A - a]DO(2)), vital capacity (VC), and carbon monoxide transfer factor (TLCO), but alternative serological measures have been sought. Granulocyte-macrophage colony stimulating factor (GM-CSF) neutralising autoantibody is found in patients with idiopathic acquired AP. We have investigated the interrelationships between the levels of this antibody and those of surfactant protein (SP)-A and -B, lactate dehydrogenase (LDH), and conventional measures of disease severity, and the capacity of these parameters to predict the response to rhGM-CSF treatment.

METHODS

Blood levels of anti-GM-CSF antibodies, SP-A, SP-B, LDH, and [A - a]DO(2), VC, and TLCO were measured before rhGM-CSF treatment and every 2 weeks thereafter in 14 patients with AP.

RESULTS

At baseline, high levels of anti-GM-CSF antibodies and increased SP-A and SP-B levels were seen in all patients, and LDH was raised in 83%. SP-A was highly correlated with [A - a]DO(2), VC, and TLCO (p</=0.02), but other markers were not. Only a normal LDH level was predictive of a response to rhGM-CSF treatment (p=0.03). During treatment a correlation between conventional and serological variables within patients was seen only between SP-A and [A - a]DO(2) (p=0.054), LDH levels and [A - a]DO(2) (p=0.010), and LDH levels and VC (p=0.019).

CONCLUSIONS

Of the serological parameters studied, only SP-A and LDH levels were correlated with conventional measures of disease severity, with LDH most accurately reflecting [A - a]DO(2) and vital capacity. Only a normal LDH level predicted a higher likelihood of response to treatment with GM-CSF.

Change in cytokeratin 19 fragment level according to the severity of pulmonary alveolar proteinosis

A 48-year-old man was diagnosed with primary alveolar proteinosis (PAP). Whole lung lavage was performed for treatment, and the opacity on his chest X-ray completely disappeared. The value of cytokeratin 19 fragment (CYFRA) in the serum was high at the beginning, decreased after lung lavage, and became elevated again when the disease recurred 7 months later. As PAP is thought to be a problem of surfactant secreted from type II pneumocytes, and a cytokeratin is present in the alveolar epithelial tissue, the value of serum CYFRA might be related to the severity of PAP.

A case of myelodysplastic syndrome complicated by pulmonary alveolar proteinosis with a high serum KL-6 level

Serious hematological diseases often cause respiratory disorders. Because these are related to the prognoses of patients with hematological diseases, their early diagnosis is necessary. This study describes a 6-year-old girl with myelodysplastic syndrome complicated by pulmonary alveolar proteinosis who showed a remarkable increase in her serum KL-6 level. Three years and 2 months after the end of therapy for neonatal melanoma, a diagnosis of myelodysplastic syndrome with leukemic change was made. Ten months after the onset of leukemia, she had respiratory distress with an increased serum KL-6 level of 75,000 U/mL (reference range; < 500 U/mL). Despite various treatments for pulmonary complications, she died 3 months after developing respiratory distress. A diagnosis of pulmonary alveolar proteinosis was made at autopsy. Earlier treatment of respiratory distress could be achieved if serum KL-6 levels were examined earlier.

Serum and bronchoalveolar fluid KL-6 levels in patients with pulmonary alveolar proteinosis

Pulmonary alveolar proteinosis (PAP) is a disease characterized by the filling of alveolar spaces with periodic acid-Schiff-positive proteinaceous material and by the hypertrophy of type II pneumocytes in the alveolar interstitium. To examine if KL-6, a mucinlike glycoprotein, is useful for the diagnosis of PAP and the estimation of its activity, serum KL-6 levels in patients with PAP were measured by an enzyme-linked immunosorbent assay and compared with those of patients with other lung diseases. Furthermore, to estimate the origin of KL-6 in some patients, measurements of KL-6 levels in bronchoalveolar lavage (BAL) fluid and immunohistochemical staining of the lung tissues with a monoclonal antibody to KL-6 antigen were performed. Serum KL-6 levels in patients with PAP were extremely high and were significantly higher than those in patients with interstitial lung diseases in which elevation of serum KL-6 has been recognized. BAL-fluid KL-6 levels in patients with PAP were higher than serum levels. Both serum and BAL-fluid KL-6 levels in patients with PAP correlated well with the disease activity. Immunohistochemically, positive staining was observed in proliferating type II pneumocytes. These results suggest the usefulness of KL-6 measurement in the diagnosis and estimation of disease activity of PAP.

Enzyme-linked immunosorbent assay using F(ab')2 fragment for the detection of human pulmonary surfactant protein D in sera

We developed an enzyme-linked immunosorbent assay (ELISA) for detection of SP-D in serum using recombinant SP-D as a standard and horseradish peroxidase conjugated F(ab')2 fragment of mouse monoclonal antibody IgG to avoid the interaction of serum factors including rheumatoid factor. The use of F(ab')2 fragment dramatically decreased the value of serum SP-D concentration in rheumatoid arthritis patients without pulmonary complication to the close level of healthy volunteer. In contrast, the patients with collagen disease having interstitial pulmonary pneumonia exhibited consistently elevated levels of serum SP-D. The use of new ELISA with recombinant SP-D and F(ab')2 fragment of anti-SP-D monoclonal antibody gives a greater advantage for the accurate detection of SP-D in sera from patients with idiopathic pulmonary fibrosis, interstitial pneumonia with collagen disease and pulmonary alveolar proteinosis without interference of rheumatoid factor.

[Successful treatment of pulmonary alveolar proteinosis by massive bronchoalveolar lavage]

In two patients with pulmonary alveolar proteinosis, PaO2 was normalized by massive bronchoalveolar lavage (BAL). Patient 1: A 29-year-old man presented with exertional dyspnea and a PaO2 of 57.8 mmHg. After four BALs, the PaO2 was 106.4 mmHg. For ten years thereafter he has been doing well. Patient 2: A 58-year-old women presented with extertional dyspnea and a PaO2 of 64.4 mmHg. The PaO2 increased to 110.6 mmHg after four BALs. BAL required much skill, but it is one of the most effective methods for the treatment of pulmonary alveolar proteinosis. Because this condition is related to an interstitial process, these two patients need to be followed carefully.

Elevation of tumour markers in serum and bronchoalveolar lavage fluid in pulmonary alveolar proteinosis

It is unclear whether tumour markers are generally increased in the serum and bronchoalveolar lavage fluid (BALF) of patients with pulmonary alveolar proteinosis (PAP). To clarify this point, levels of tumour markers were measured in the serum and BALF of patients with PAP. Squamous cell carcinoma (SCC) antigen, carcinoembryonic antigen (CEA), and carbohydrate antigens sialyl Lewis (CA 19-9) and sialyl SSEA-1 (SLX) were assayed with radioimmunoassay kits. Cytokeratin 19 fragments (CYFRA) were measured by enzyme-linked immunosorbent assay. Values for the tumour markers in serum, except for SCC, exceeded cut-off values in some PAP patients. Levels of the markers were higher in BALF compared with those in serum, and were significantly elevated in PAP patients compared with control subjects. There was a significant inverse correlation between CA19-9 level in BALF and arterial oxygen tension (PaO2) in PAP patients. A gradual elevation of CA19-9 and SLX was observed in a patient who showed a decrease in PaO2 level during the study period. In the light of these findings, it is possible that levels of tumour markers in BALF, especially levels of CA19-9 and SLX, may reflect the severity of the disease in PAP patients.

Aberrant appearance of lung surfactant protein A in sera of patients with idiopathic pulmonary fibrosis and its clinical significance

Pulmonary surfactant protein A (SP-A) is known to be a major phospholipid-associated glycoprotein in pulmonary surfactant, which is specific to the lung. In this study, the SP-A concentrations in sera of patients with various lung diseases were determined using an enzyme-linked immunosorbent assay. Patients with idiopathic pulmonary fibrosis (IPF) and pulmonary alveolar proteinosis (PAP) exhibited prominently high concentrations of serum SP-A compared to those of other lung diseases and healthy volunteers, although there were significant increases in serum SP-A concentrations in patients with pulmonary tuberculosis, chronic pulmonary emphysema, diffuse panbronchiolitis and bacterial pneumonia compared to those of healthy volunteers. Successive measurement in 2 patients with IPF showed that serum SP-A levels reflect the disease activity of IPF. In patients with IPF, serum SP-A concentrations were significantly correlated with those of serum lactate dehydrogenase, whereas there were no significant correlations of serum SP-A concentrations with erythrocyte sedimentation rate, arterial oxygen saturation, vital capacity and carbon monoxide diffusing capacity. Determination of serum SP-A will contribute to diagnosing IPF and PAP, and may reflect the disease activity of IPF.

Increased carcinoembryonic antigen concentrations in sera and bronchoalveolar lavage fluids of patients with pulmonary alveolar proteinosis

Pulmonary alveolar proteinosis (PAP) is a rare disease in which alveoli are filled with lipoproteinaceous materials. We measured carcinoembryonic antigen (CEA) concentrations in bronchoalveolar lavage (BAL) fluids and sera from patients with PAP and from healthy volunteers (HV). Significantly increased CEA values were found in BAL fluids and sera from patients with PAP compared with those from HV. BAL fluid CEA values significantly correlated to serum CEA values in patients with PAP. Serum CEA values significantly correlated to serum lactate dehydrogenase activity and alveolar-arterial PO2 difference values in patients with PAP. Successive measurements of serum CEA showed that serum CEA values reflect the disease activity of PAP. The determination of serum CEA is useful for evaluating disease severity of PAP.

Elevated levels of lung surfactant protein A in sera from patients with idiopathic pulmonary fibrosis and pulmonary alveolar proteinosis

An enzyme-linked immunosorbent assay using monoclonal antibodies to human lung surfactant protein A (SP-A) was applied to sera from patients with lung diseases. We examined whether SP-A appears in the sera of patients with diseases that are known to cause alterations in surfactant composition in bronchoalveolar lavage fluids, and we characterized the SP-A that was found. The level of SP-A in sera from 57 healthy volunteers was 45 +/- 3 ng/ml (mean +/- SEM). The levels in patients with idiopathic pulmonary fibrosis (IPF) (205 +/- 23 ng/ml, n = 32) and pulmonary alveolar proteinosis (PAP) (285 +/- 23 ng/ml, n = 6) were significantly higher than those in healthy control subjects (p < 0.01), whereas those of sarcoidosis (n = 16), pneumonia (n = 14), and tuberculosis (n = 14) were 52 +/- 27 ng/ml, 65 +/- 11 ng/ml, and 49 +/- 23 ng/ml, respectively. Electrophoresis and immunoblotting analysis demonstrated that the fraction isolated from serum of a patient with PAP or IPF by anti-SP-A immunoaffinity column chromatography consisted chiefly of human IgG and IgM, and that it also contained SP-A. Furthermore, IgG was found in preparation of purified human SP-A. SP-A was demonstrated to bind to nonimmune IgG coated onto microtiter wells. Gel filtration analysis revealed that serum SP-A was eluted at fractions of larger molecular size than was the purified SP-A. These findings suggest that SP-A appears in the bloodstream as a complex with immunoglobulin in IPF and in PAP.

Hemodynamic changes during whole bronchoalveolar lavage in two cases of pulmonary alveolar proteinosis

Five whole bronchoalveolar lavages were performed in 2 patients with pulmonary alveolar proteinosis with continuous monitoring of mixed venous and arterial oxygen saturation. Hemodynamic parameters and gas-exchange status were measured during the different phases of the lavage. In the phase of filled lung, a significant increase of arterial partial pressure (PaO2) and arterial saturation of oxygen were observed, secondary to a decrease in the intrapulmonary shunt. The mean pulmonary arterial pressure, pulmonary vascular resistances and cardiac index were higher during the filling of the lung as compared to the controls. During the empty lung phase, although PaO2 decreased (without reaching statistical significance), due to an increase in the intrapulmonary shunt, the increase in cardiac output during this phase left the oxygen delivery (DO2) unchanged.

[Two cases of pulmonary alveolar proteinosis with increase of serum CEA]

Two cases of pulmonary alveolar proteinosis with increased serum CEA were reported. In both cases, the clinical diagnosis of pulmonary alveolar proteinosis was confirmed by transbronchial lung biopsy (TBLB). Immunohistochemical study of the lung biopsy specimen showed that CEA staining was present in the region of alveoli where type II alveolar epithelial cells proliferate. It was suggested that proliferative type II cells produced CEA in pulmonary alveolar proteinosis. The study of cell surface markers in their bronchoalveolar lavage fluid (BALF) revealed increase of CD8 and Leu7 positive cells and decrease of CD4 positive cells. In the case 2, there was significant increase of B lymphocytes marker positive cells. These results suggested that there may be abnormal regulation of both T and B lymphocytes and NK cells, leading to dysfunction of the pulmonary alveolar macrophage in pulmonary alveolar proteinosis.

Extracorporeal membrane oxygenation during bronchopulmonary lavage

Extracorporeal membrane oxygenation (ECMO) in a venoarterial perfusion circuit was used to provide support of gas exchange during bronchopulmonary lavage in a 32-year-old man with pulmonary alveolar proteinosis and severe arterial hypoxemia. Prior to the lavage, Pao2 during mechanical ventilation with 100% oxygen and positive end-expiratory pressure was only 125 mm Hg. Extracorporeal perfusion at a flow rate of 3 liters/min, with oxygen delivery of 244 ml/min, increased the Pao2 to 227 mmHg and lowered the mean pulmonary artery pressure from 28 to 24 mm Hg. During bronchopulmonary lavage and ECMO, the Pao2 ranged between 46 and 96 mm Hg. After the procedure, pulmonary performance decidely improved. By reducing the chances of fatal hypoxemia, ECMO allowed treatment to be instituted for this potentially reversible disorder and proved helpful as a form of support during the management of pulmonary alveolar proteinosis when severe hypoxemia may have other wise precluded bronchopulmonary lavage.