Serum levels of KL-6 as a useful marker for evaluating pulmonary fibrosis in patients with systemic sclerosis

OBJECTIVE: KL-6 is a mucin-like glycoprotein that is strongly expressed on type II pneumocytes in the lung. Circulating KL-6 has been shown to be a sensitive marker of the disease activity of interstitial lung diseases. We determined the serum levels of KL-6 in patients with systemic sclerosis (SSc) and investigated whether these levels would serve as a useful marker of pulmonary fibrosis (PF) in patients with SSc. METHODS: The serum KL-6 levels were determined using a specific ELISA in 91 patients with SSc, and in 38 healthy controls. RESULTS: The serum levels of KL-6 were significantly higher in patients with SSc than in healthy controls (923+/-860 vs. 382+/-55 U/ml; p<0.0001). The serum KL-6 levels of the patients with diffuse cutaneous SSc (dSSc) tended to be higher than those with limited cutaneous SSc (ISSc) (1054+/-1000 vs. 800+/-694 U/ml), but there was no significant difference between these 2 groups. The serum KL-6 levels in the patients with PF were significantly elevated compared to those without PF (1283+/-1056 vs. 520+/-148 U/ml; p<0.0001). Moreover, DLCO and VC were also significantly decreased in the patients with elevated KL-6 levels compared to those with normal levels (62+/-22% vs. 72+/-17%, p<0.05; 87 +/-20% vs. 100+/-18%, p<0.01, respectively). CONCLUSION: Serum KL-6 level may be a useful serum marker for evaluating pulmonary fibrosis in patients with SSc.     

Comparative study of serum surfactant protein-D and KL-6 concentrations in patients with systemic sclerosis as markers for monitoring the activity of pulmonary fibrosis

OBJECTIVE: To clarify the clinical significance of surfactant protein-D (SP-D) and KL-6 in the diagnosis and monitoring of pulmonary fibrosis (PF) in patients with systemic sclerosis (SSc), and to evaluate the differences between SP-D and KL-6. METHODS: Serum SP-D and KL-6 concentrations were determined by ELISA in 42 SSc patients. In a retrospective longitudinal study, 83 serum samples from 6 SSc patients were analyzed during a followup period of 0.6-6.3 years. RESULTS: SP-D and KL-6 concentrations at the first visit were higher in patients with SSc, especially those with PF, compared with healthy controls. Increased concentrations of SP-D were associated with decreased DLCO and decreased vital capacity in SSc patients more strongly than those of KL-6. The sensitivity and specificity for PF were 91% and 88% for SP-D and 39% and 100% for KL-6, respectively. In the longitudinal study, both SP-D and KL-6 concentrations were associated with activity of PF in patients with SSc. SP-D concentrations changed more rapidly than KL-6 concentrations, in parallel with the PF activity. CONCLUSION: SP-D was a more sensitive marker for PF than KL-6. By contrast, KL-6 showed higher specificity than SP-D. Combined use of these 2 serum markers would be more helpful to diagnose and monitor the PF activity in patients with SSc than single use of each marker.     

Serum pulmonary and activation-regulated chemokine/CCL18 levels in patients with systemic sclerosis: a sensitive indicator of active pulmonary fibrosis

OBJECTIVE: To clarify the clinical significance of serum levels of pulmonary and activation-regulated chemokine (PARC) in the diagnosis and monitoring of pulmonary fibrosis (PF) in patients with systemic sclerosis (SSc) and to compare PARC levels with KL-6 antigen or surfactant protein D (SP-D) levels. METHODS: Serum PARC levels were determined by enzyme-linked immunosorbent assay in 123 SSc patients. In a retrospective longitudinal study, correlation of serum PARC levels with the activity of PF was assessed in 21 SSc patients with active PF. RESULTS: PARC levels at the first visit were higher in patients with SSc than in patients with systemic lupus erythematosus (SLE) or healthy controls. Increased serum PARC levels were associated with involvement of PF, decreased diffusing capacity for carbon monoxide, and decreased vital capacity in SSc patients. In the longitudinal study, serum PARC levels were significantly decreased in SSc patients with inactive PF compared with those with active PF. CONCLUSION: Elevated serum PARC levels correlated with PF and more sensitively reflected the PF activity than did serum KL-6 or SP-D levels in SSc. Serum PARC levels may be a useful new serum marker for active PF in SSc.     

Clinical significance of surfactant protein D as a serum marker for evaluating pulmonary fibrosis in patients with systemic sclerosis

Objective

To determine the clinical significance of surfactant protein D (SP‐D), a useful marker for evaluating various lung diseases, in patients with systemic sclerosis (SSc) and to clarify any clinical significance between SP‐D and KL‐6, which is known to be correlated with pulmonary fibrosis (PF) in SSc patients.

Methods

We used a specific enzyme‐linked immunosorbent assay to measure serum SP‐D levels in 83 patients with SSc and 31 healthy control subjects.

Results

The serum levels of SP‐D were significantly higher in patients with SSc than in healthy controls (mean ± SD 81.9 ± 59.2 versus 34.8 ± 13.7 ng/ml). Serum SP‐D levels in patients with diffuse cutaneous SSc were significantly higher than those in patients with limited cutaneous SSc (98.8 ± 72.1 versus 66.8 ± 40.0 ng/ml). Serum SP‐D levels in patients with PF were significantly elevated compared with those in patients without PF (99.7 ± 64.1 versus 65.3 ± 49.4 ng/ml). Moreover, the incidences of decreased percentage diffusing capacity for carbon monoxide and decreased percentage vital capacity were also significantly greater in patients with elevated SP‐D levels than in those with normal levels (67% versus 43% and 36% versus 17%, respectively). There was a significant positive correlation between serum levels of SP‐D and KL‐6. Serum SP‐D and KL‐6 levels showed almost the same sensitivities and specificities in the diagnosis of PF (68% versus 73% and 70% versus 74%, respectively). These two markers also predicted PF to almost the same degree (31% versus 33%, respectively).

Conclusion

These results suggest that SP‐D, as well as KL‐6, may be a useful serum marker for evaluating PF in patients with SSc.

     

Comprehensive investigation of novel serum markers of pulmonary fibrosis associated with systemic sclerosis and dermato/polymyositis

OBJECTIVE: To investigate the association between serum levels and clinical signs of lung fibrosis in patients with systemic sclerosis and inflammatory myopathies. METHODS: ELISA tests for a mucin-like glycoprotein KL-6, von Willebrandt factor (vWF), soluble E-selectin (sES) and surfactant protein D (SP-D) were performed in sera of 104 patients with systemic sclerosis, 31 patients with poly/dermatomyositis) and 24 patients with Raynaud's phenomenon as controls. The clinical and laboratory data were evaluated by a simple standard protocol including chest x-ray, lung function tests, echocardiography and, in selected cases, high resolution computer tomography (HRCT). Clinically significant pulmonary fibrosis (PF) defined as a simultaneous presence of radiological sign of pulmonary fibrosis and restrictive impairment. Severe PF was established if HRCT scans showed diffuse interstitial lung disease with low diffusing capacity. End stage PF was determined as severe PF with very low diffusing capacity. RESULTS: Patients with pulmonary fibrosis on chest x-ray showed significantly elevated serum levels of KL-6, SP-D and vWF. Inverse correlation was found between serum levels of KL-6/SP-D and lung function parameters, such as DLCO% and FVC. With regard to HRCT findings, patients with elevated serum level of KL-6 showed significantly more frequently ground glass opacity, diffuse and honeycombing fibrosis than patients with normal level of KL-6. The sensitivity of KL-6 for PF in SSc is increased with the severity of PF (PF on chest x-ray < severe PF < end stage of PF). Lung fibrosis occurred more frequently in patients with simultaneously elevated KL-6 and sES compared to cases with a single positivity of either KL-6 or sES. CONCLUSION: KL-6, SP-D, vWF and ES are good surrogate factors of pulmonary fibrosis but can not replace conventional diagnostic procedures. However, these markers are suitable for the assessment of progression and severity of pulmonary fibrosis in systemic autoimmune disorders once the diagnosis is established.     

Pulmonary disorders in indium-processing workers]

The production of indium-tin oxide has increased during the past decade, owing to the increased manufacture of liquid-crystal panels, especially in Japan. We carried out a medical checkup including high resolution CT (HRCT), pulmonary function test, KL-6, SP-D and serum indium concentration, for 40 men (mean age 40.4 +/- 12.4 years old) working in an indium plant. Four workers who were all smokers had emphysematous changes on HRCT and one subject (non-smoker) had lung cancer. There were no findings of interstitial changes on HRCT. Serum KL-6 was significantly elevated (over 500U/ml) in 9 subjects (22.5%). Subjects with a high concentration of serum indium (3ng/ml<) had significantly longer exposure periods, higher KL-6 and SP-D levels compared with those with a low concentration (3ng/ml>). The serum indium concentration positively correlated with the KL-6 level. These results suggest that inhaled indium compounds can cause pulmonary disorders such as interstitial changes.     

Longitudinal analysis of serum KL-6 levels in patients with systemic sclerosis: association with the activity of pulmonary fibrosis

OBJECTIVE: To determine whether changes in serum KL-6 levels reflect the activity of pulmonary fibrosis (PF) in patients with systemic sclerosis (SSc). METHODS: KL-6 levels were determined by ELISA in 39 SSc patients. In a retrospective longitudinal study, 250 serum samples were analyzed during a follow-up period of 0.3-6.1 years. RESULTS: KL-6 levels at the first visit were higher in patients with SSc, especially with PF, compared with healthy controls. In the longitudinal study, KL-6 levels in 4 patients with anti-topo I Abs increased rapidly, parallel to the progression of PF. Four patients with inactive PF exhibited elevated, but stable levels of KL-6 during the follow-up. The 31 patients with almost normal KL-6 levels during the follow-up exhibited no deterioration or new onset of PF. CONCLUSION: Rapidly increased serum KL-6 levels during disease course were associated with new onset or deterioration of PF.     

Clinical significance of serum levels of matrix metalloproteinase-13 in patients with systemic sclerosis

OBJECTIVES: To investigate the clinical significance of serum matrix metalloproteinase-13 (MMP-13) levels in patients with systemic sclerosis (SSc). METHODS: Serum MMP-13 levels were determined by using a peptide substrate cleavage assay in 20 patients with diffuse cutaneous SSc (dcSSc), 20 with limited cutaneous SSc (lcSSc) and 10 normal controls. RESULTS: The serum MMP-13 levels in patients with dcSSc or lcSSc were significantly lower than those in normal controls (53.4 +/- 14.1 vs 73.2 +/- 11.5 ng/ml, P < 0.0005; 59.4 +/- 14.8 vs 73.2 +/- 11.5 ng/ml, P < 0.005, respectively), but there was no significant difference in the serum MMP-13 levels between patients with dcSSc and those with lcSSc. Disease duration prior to the diagnosis was significantly shorter in SSc patients with decreased serum MMP-13 levels than in those with normal levels (3.0 +/- 2.2 vs 8.6 +/- 7.6 yr, P < 0.0005). In addition, serum MMP-13 levels were moderately correlated with the duration of the disease (r = 0.451, P < 0.05). Though there was no significant difference in the frequencies of pulmonary fibrosis or reduced %DLco (diffusing capacity of lung for carbon monoxide), the frequency of reduced %VC (vital capacity) was significantly greater in patients with decreased serum MMP-13 levels than in those with normal levels (73 vs 24%, P < 0.05). CONCLUSIONS: Matrix metalloproteinase-13 may be involved in the fibrotic process of SSc, especially in the initiation of fibrosis. The serum MMP-13 levels may serve as a useful marker for the severity of pulmonary fibrosis in patients with SSc.     

Serum KL-6 and surfactant proteins A and D in pediatric interstitial lung disease

OBJECTIVE: To determine if serum KL-6, surfactant protein A (SP-A), and surfactant protein D (SP-D) levels are elevated in pediatric interstitial lung disease (ILD) and associated with pulmonary function and disease severity score. METHODS: Serum KL-6, SP-A, and SP-D levels were measured by enzyme-linked immunosorbent assay in 10 children with ILD and in 10 healthy volunteers. In the ILD group, FEV1 percentage of predicted, FVC percentage of predicted, and ILD disease severity score were measured and correlated with serum KL-6, SP-A, and SP-D levels. RESULTS: For the ILD and control groups, respectively, mean serum KL-6 was 4,523 U/mL and 206 U/mL (p = 0.007), mean serum SP-A was 133 ng/mL and 21 ng/mL (p = 0.003), and mean serum SP-D was 304 ng/mL and 75 ng/mL (p = 0.004). There was an inverse relationship between SP-A and FVC (p = 0.05), and between SP-D and FEV1 (p = 0.05). There was a direct relationship between SP-D and ILD score (p = 0.05). CONCLUSIONS: Serum KL-6, SP-D and SP-D levels are elevated in children with ILD. SP-A and SP-D levels appear to correlate with some measures of disease severity.     

Clinical significance of serum surfactant protein D (SP-D) in patients with polymyositis/dermatomyositis: correlation with interstitial lung disease

OBJECTIVE: To determine the clinical significance of serum surfactant protein D (SP-D) levels in patients with polymyositis/dermatomyositis (PM/DM). METHODS: Serum SP-D levels were assayed using a sensitive enzyme-linked immunosorbent assay in 59 patients with PM/DM and in 29 healthy controls. RESULTS: The serum level of SP-D was significantly higher in patients with PM/DM than in healthy controls (mean+/-S.D. 61.7+/-122.6 vs 31.0+/-12.4 ng/ml, P < 0.01). The serum SP-D level in patients with interstitial lung disease (ILD) was significantly higher than in those without ILD (118.7+/-220.2 vs 38.7+/-21.0 ng/ml, P < 0.001). Serum level of SP-D was correlated with the presence of ILD. The incidences of decreased vital capacity (%VC) and of decreased diffusing capacity of carbon monoxidase (%DLCO) were also significantly greater in patients with an elevated SP-D level than in those with a normal level (64 vs 7%, P < 0.02; 73 vs 27%, P < 0.01). Moreover, the serum SP-D level was inversely correlated with %VC (r=-0.452, P < 0.01) and %DLCO (r=-0.349, P < 0.05). CONCLUSION: The serum SP-D level may be a useful marker for ILD in patients with PM/DM.     

The usefulness of serum KL-6 levels for the diagnosis of disease activity in idiopathic interstitial pneumonia]

Serum KL-6 levels were measured in 29 patients with idiopathic interstitial pneumonia (IIP) as a means of evaluating disease activity. Levels of serum KL-6 were significantly higher in patients with active IIP (n = 11) than in those with inactive IIP (n = 18). The levels of serum KL-6 were 2,546 +/- 1,703 U/ml in patients with active IIP and 795 +/- 385 U/ml in patients with inactive IIP, respectively. The levels of serum LDH, CEA, P-III-P, and 7 S collagen in patients with active IIP did not differ significantly from those in patients with inactive IIP. For the diagnosis of active IIP, the sensitivity of serum KL-6 (cut off value of 1,500 U/ml) was 81.8% and the specificity, 94.4%. These results were almost identical to findings obtained with chest Ga-67 scintigraphy. Furthermore, they suggested that serum KL-6 levels may be a useful marker for the diagnosis of disease activity in IIP, as well as a useful indicator for the administration of steroid therapy to patients with IIP.     

Serum level of KL-6 as a marker of interstitial lung disease in patients with juvenile systemic sclerosis

OBJECTIVE: Serum KL-6 has been found to be elevated in diseases characterized by diffuse interstitial lung involvement. The purpose of this study was to evaluate serum KL-6 as a marker of interstitial lung disease (ILD) in patients with juvenile systemic sclerosis (JSS). METHODS: Serum concentrations of KL-6 were measured with an immunoassay in 39 serum samples from 12 children with diffuse cutaneous form of JSS (6 patients with and 6 patients without ILD) and from 20 healthy controls comparable for age. In patients sampled serially, the relationship of KL-6 concentrations with the severity of ILD and its response to treatment were evaluated. RESULTS: Serum concentrations of KL-6 were significantly higher in patients with ILD (1687 +/- 979 IU/ml) than in patients without (345 +/- 95 IU/ml, p < 0.01) and healthy controls (311 +/- 114 IU/ml, p < 0.001). Serum KL-6 concentrations of patients without ILD were not statistically different from those of healthy controls. We found a significant correlation of serum KL-6 concentrations with vital capacity and with diffusing capacity for carbon monoxide (DLCO). Analysis of individual patients showed that serum concentrations of KL-6 were correlated with ILD severity and its response to treatment. CONCLUSION: Measurement of serum KL-6 concentration is a useful noninvasive marker of pulmonary fibrosis in children with JSS. Its advantages over conventional methods of ILD assessment, such as pulmonary function test and high-resolution computerized tomography, are that it is easy to quantify and to measure repeatedly and it does not need children's cooperation.     

Elevated vascular endothelial growth factor in systemic sclerosis

OBJECTIVE: To determine the serum levels of vascular endothelial growth factor (VEGF) in patients with systemic sclerosis (SSc) and to search for relationships between its serum levels and the clinical manifestations. METHODS: Serum levels of VEGF in patients with SSc and healthy controls were determined by ELISA. At the time of blood sampling, individual organ involvement was assessed, and a video microscope and PC based image processing were used to visualize nailfold capillaries and to quantify capillary density. RESULTS: Serum levels of VEGF in 48 patients with SSc were significantly higher than in 30 controls (432 +/- 356 vs 91 +/- 64 pg/ml; p < 0.001). Patients with diffuse cutaneous SSc (n = 21) had higher levels of serum VEGF than those with limited cutaneous SSc (n = 27) (432 +/- 356 vs 135 +/- 127 pg/ml; p < 0.001). Serum VEGF levels correlated well with the extent of skin sclerosis, as determined by modified Rodnan skin score (r = 0.656, p < 0.001) and serum TGF-beta levels (r = 0.530, p < 0.001). In particular, serum VEGF levels were inversely correlated with the capillary density of nailfold (r = -0.649, p < 0.001). However, no significant differences were found in the serum levels of VEGF between patients with systemic organ involvement and those without. CONCLUSION: The extent of skin sclerosis may contribute to the elevation of serum VEGF and high VEGF levels may serve as a surrogate indicator of capillary damage in SSc.     

Neuron specific enolase concentration is increased in serum and decreased in platelets of patients with active systemic sclerosis

OBJECTIVE: To determine frequency, origin, and clinical associations of elevated serum neuron specific enolase (NSE) in systemic sclerosis (SSc). METHODS: Serum was obtained from 75 patients with SSc, 20 systemic lupus erythematosus, 8 polymyositis, 10 idiopathic interstitial lung disease, and 10 healthy volunteers. NSE status was determined in serum (in all individuals) and in platelet lysate (in volunteers and 30 patients with SSc). RESULTS: Elevated serum NSE (mean 22.6 ng/ml, range 12.1-68.2 ng/ml) was observed in 26 patients with SSc (34.6%). Those with diffuse SSc had higher serum NSE than those with limited disease (16.5 +/- 13.4 vs 9.6 +/- 5.0 ng/ml, p = 0.006). No association was found between serum NSE and lung or esophagus involvement. Patients with long-standing disease had lower serum NSE than those with early disease (10.8 +/- 7.3 vs 16.1 +/- 13.6 ng/ml, p = 0.05). Serum NSE was 19.4 +/- 13.0 ng/ml in patients with total skin score (TSS) > 20, 8.3 +/- 2.1 ng/ml in patients with TSS < 5, and 6.0 +/- 3.1 ng/ml in volunteers (p = 0.01). NSE platelet lysate concentration was 3.6 +/- 2.9 ng/ml in patients with TSS > 20, 12.4 +/- 4.1 ng/ml in those with TSS < 5, and 14.1 +/- 6.5 ng/ml in healthy individuals (p < 0.001). Volunteers and SSc patients with low TSS had comparable S/PL-NSE index (serum/platelet lysate NSE concentration) (0.42 +/- 0.16 and 0.75 +/- 0.33, respectively), both lower than SSc patients with high TSS (7.45 +/- 5.57) (p < 0.001). CONCLUSION: Elevated serum NSE was observed in one-third of SSc patients but not in other autoimmune rheumatic diseases. The inverse relationship between serum and platelet lysate NSE concentration suggests platelet activation as the origin of high serum NSE in SSc. NSE S/PL was the best discriminatory variable between healthy volunteers and SSc patients as well as between patients with high and low TSS. High serum NSE and high NSE-S/PL index seemed to be associated with SSc disease activity. Further work is warranted to investigate a possible role for this marker in assessing disease activity and therapy response.     

Clinical significance of serum KL-6 and SP-D for the diagnosis and treatment of interstitial lung disease in patients with diffuse connective tissue disorders]

OBJECTIVE: To elucidate the clinical significance of serum KL-6 and SP-D for the diagnosis and treatment of interstitial lung disease in connective tissue disorders. METHODS: 139 patients with various connective tissue disorders were subjected for the study, which included 46 cases of rheumatoid arthritis, 43 cases of Sj?gren's syndrome, 16 cases of SLE, 10 cases of systemic sclerosis, 9 cases of polymyositis/dermatomyositis, 6 cases of vasculitis syndrome, 5 cases of Beh?et's disease and 4 cases of MCTD. Serum levels of KL-6 and SP-D were determined by enzyme-immunoassay. The sensitivity, specificity and accuracy of serum KL-6 and SP-D for the diagnosis of interstitial lung disease were compared with serum LDH. The relationship of serum KL-6 and SP-D levels with high resolution CT (HRCT) of the lung and Gallium scintigraphy findings was analyzed. In some cases, serum levels of the two markers were determined monthly in the course of the disease. RESULTS: When the serum levels of KL-6 and SP-D were measured simultaneously, the sensitivity to diagnose interstitial lung disease was 67.7%, the specificity was 98.1%, and the accuracy was 91.4%, while those of serum LDH were 45.2%, 88.9%, 79.1% respectively. In the patients with interstitial lung disease, those who had elevated serum levels of both KL-6 and SP-D showed parenchymal collapse opacity-dominant pattern in HRCT. On the other hand, the patients with interstitial lung disease who had normal levels of serum KL-6 and SP-D or had elevation either in KL-6 or SP-D levels showed ground glass opacity-dominant pattern in HRCT. There was no significant correlation between serum marker levels and Gallium scintigraphy findings. When serum KL-6 and SP-D were measured monthly, the levels of both markers changed more specifically and sensitively to the lung disease activity compared with serum LDH. CONCLUSIONS: Serum KL-6 and SP-D are more specific and useful markers for the diagnosis and evaluation of interstitial lung disease compared with serum LDH in connective tissue disorders.     

Functional hyperprolactinemia and hypophyseal microadenoma in systemic sclerosis

OBJECTIVE: Hyperprolactinemia (HPRL) has been identified in more than half of patients with systemic sclerosis (SSc). However, the association with pituitary adenoma and the status of hypothalamic dopaminergic tone using metoclopramide (MTC) test has not been studied. We investigated the prevalence of prolactin (PRL)-secreting pituitary adenoma and evaluated production of PRL by dynamic testing with MTC in SSc. METHODS: We studied 30 patients with SSc (mean age 38 +/- 10 yrs) and 20 healthy controls (mean age 37 +/- 11 yrs). Serum PRL concentrations were determined by radioimmunoassay in all subjects, and PRL response was measured 30, 60, 90, and 120 min after injection of 10 mg of MTC. Computed tomography (CT) of the sella turcica was performed. RESULTS: The mean basal serum PRL levels before and after stimulation with MTC in SSc patients versus controls were: basal 18.2 +/- 5.4 versus 8.7 +/- 1.6 ng/ml, p = NS; 30 min: 175.0 +/- 5.4 versus 61.0 +/- 42 ng/ml, p < 0.001; 60 min: 160 +/- 64 versus 52 +/- 30 ng/ml, p < 0.001; 90 min: 125 +/- 57 versus 42 +/- 21.0 ng/ml, p < 0.05; 120 min: 108.0 +/- 57 versus 30.0 +/- 10 ng/ml, p < 0.005. CT scan showed microadenomas in 24/30 SSc patients and 1/20 controls (p = 0.001). CONCLUSION: Our study suggests that a group of patients with SSc have a high prevalence of HPRL with increased central dopaminergic tone, and microadenomas. PRL may have a role in the pathogenesis of SSc. Further studies are necessary to confirm our results.     

Elevation of serum KL-6 levels in patients with hematological malignancies associated with cytomegalovirus or Pneumocystis carinii pneumonia

The level of serum KL-6 antigen has been reported to be a sensitive indicator of various interstitial pneumonitis, but in patients with hematological malignancies who were accompanied by infective interstitial pneumonitis like Pneumocystis carinii or cytomegalovirus (CMV) pneumonia, it is still unknown whether serum KL-6 level is useful as a good marker for the diagnosis or disease activity. In this study, the serum levels of KL-6 and soluble intercellular adhesion molecule 1 (sICAM-1) were evaluated in five patients with malignant lymphoma or adult T-cell leukemia. Serum KL-6 and sICAM-1 levels at the time of diagnosis of P. carinii or CMV pneumonia were 1220+/-323 U/ml (mean+/-SD) and 1246+/-485 ng/ml, respectively. These levels were apparently high, when compared with standard value of serum KL-6 (<520 U/ml) and that of sICAM-1 (115-306 ng/ml). In patients without P. carinii or CMV pneumonia, who had hematological malignancies or AIDS, serum level of KL-6 was not high (299+/-122 U/ml), but sICAM-1 was high (651+/-495 ng/ml) because of the elevation of sICAM-1 in four of five cases. These findings suggest that, in patients with hematological malignancies, serum level of KL-6 antigen rather than sICAM-1 may be useful in the evaluation of CMV or P. carinii pneumonia.     

Comparative study of KL-6, surfactant protein-A, surfactant protein-D, and monocyte chemoattractant protein-1 as serum markers for interstitial lung diseases

KL-6, surfactant protein (SP)-A, SP-D, and monocyte chemoattractant protein-1 (MCP-1) are reported to be sensitive markers for interstitial lung diseases (ILD). However, each marker has been studied independently. The aim of this study was a comparative analysis of the diagnostic values of these markers. Subjects consisted of 33 patients with ILD (21 cases of idiopathic pulmonary fibrosis and 12 associated with collagen vascular diseases) and 82 control subjects (12 cases of bacterial pneumonia and 70 healthy volunteers). Receiver operating characteristic curves revealed that KL-6 was superior to the other markers. The cut-off levels for these markers that resulted in the highest diagnostic accuracy were determined to be 465 U/ml for KL-6, 48.2 ng/ml for SP-A, 116 ng/ml for SP-D, and 1080 pg/ml for MCP-1. The sensitivity, specificity, and diagnostic accuracy were 93.9%, 96.3%, and 95.7% for KL-6; 81.8%, 86.6%, and 85.2% for SP-A; 69.7%, 95.1%, and 87.8% for SP-D; and 51.5%, 92.7%, and 80.9% for MCP-1; respectively. The serum levels of SP-A and SP-D, but not of KL-6, were significantly higher in patients with bacterial pneumonia than in healthy volunteers. These results suggest that of the markers studied, KL-6 is the best serum marker for ILD.     

Clinical significance of serum levels of secretory leukocyte protease inhibitor in patients with systemic sclerosis

We aimed to investigate the clinical significance of serum levels of secretory leukocyte protease inhibitor (SLPI), which is widely expressed in lung tissues and serves as a useful marker reflecting the activity of various lung diseases, in patients with systemic sclerosis (SSc). Serum SLPI levels were measured by a specific enzyme-linked immunosorbent assay (ELISA) in 58 SSc patients and 16 healthy controls. Serum SLPI levels in diffuse cutaneous SSc and in limited cutaneous SSc with interstitial lung disease (ILD) were significantly higher than those in healthy controls (43.1?±?18.4 vs. 30.9?±?3.76?ng/ml, p?相似文献   

Marked increase in serum KL-6 and surfactant protein D levels during the first 4 weeks after treatment predicts poor prognosis in patients with active interstitial pneumonia associated with polymyositis/dermatomyositis

Objective

The aim of this study is to determine whether serum KL-6 and surfactant protein D (SP-D) levels predict the prognosis of patients with interstitial pneumonia (IP) in cases of polymyositis (PM) and dermatomyositis (DM).

Patients and methods

Fifty consecutive patients with PM (n = 17) or DM (n = 33) and active IP, 6 of whom died of respiratory failure, were enrolled in this study. Serum KL-6 and SP-D levels were measured every 2–4 weeks. Medical records were reviewed retrospectively. Univariate analyses and multivariate analyses with a logistic regression model were conducted.

Results

Serum KL-6 and SP-D levels were elevated in patients with active IP. At the time of diagnosis of active IP, the serum KL-6 level was within the normal range in 28 % of patients and the SP-D level was within the normal range in 46 % of patients. Serum KL-6 level increased up to 3 months after starting treatment and then decreased gradually to baseline, whereas SP-D level peaked within the first 4 weeks after treatment and decreased rapidly to normal levels. Patients with poor prognosis showed increases in KL-6 and SP-D levels during the first 4 weeks after treatment, which was confirmed by uni- and multivariate analyses. Comparing the marker levels at 2–4 weeks after treatment with those at 0 weeks, an increase in the ratio over 1.70 for KL-6 and over 1.75 for SP-D, and an increase in KL-6 over 850 U/ml during the first 4 weeks after treatment, were poor prognostic factors.

Conclusions

Increases in serum KL-6 and SP-D levels during the first 4 weeks after starting therapy, but not their levels at any one time point, predict poor prognosis in patients with PM/DM. When marked increases of KL-6 and SP-D levels during the first 4 weeks are found or are predicted by serial measurement of the markers, patients have risks of poor prognosis and additional therapy should be considered.