Prognosis of fibrotic interstitial pneumonia: idiopathic versus collagen vascular disease-related subtypes

BACKGROUND: To investigate whether the better prognosis of interstitial pneumonias associated with collagen vascular disease (CVD) compared with idiopathic interstitial pneumonia (IIP) is due to higher frequency of the nonspecific interstitial pneumonia (NSIP) pattern in CVD, we compared the outcomes of patients from these two groups with the same histopathologic pattern. SUBJECTS: The clinical features and survival of 362 patients (269 with IIP and 93 with CVD) diagnosed using surgical lung biopsy were analyzed. RESULTS: The mean survival of the CVD group (131.0 mo) was longer than that of the IIP group (80.5 mo) (p<0.0001). The patients with usual interstitial pneumonia pattern among the CVD group (n=36) was younger, female, and predominantly nonsmoking compared with the IIP group (n=203). Although baseline lung functions were not significantly different, the CVD group survived longer (mean, 177.0 mo) than the IIP group (mean, 66.9 +/- 6.5 mo; p=0.001). By multivariate analysis, younger age, better pulmonary function, and the presence of a CVD were independent prognostic factors. In NSIP pattern, no significant differences in survival, clinical features, or lung function were found between the two groups. CONCLUSION: Our data suggest that the better prognosis of patients in the CVD group is not solely due to the predominance of the NSIP pattern. The prognosis of patients with the usual interstitial pneumonia pattern in CVD is better than in those with idiopathic pulmonary fibrosis, despite the same pathologic pattern. In contrast, in those with an NSIP pattern, the prognosis is similar in both groups.     

A prospective study of lung cancer in cases of idiopathic interstitial pneumonia (IIP)]

The incidence of lung cancer in 45 patients (37 males and 8 females), who were originally diagnosed as having idiopathic interstitial pneumonia (IIP), was studied prospectively by following them 4 to 10 years. As controls, sex-, age-, and smoking history matched patients with chronic obstructive lung disease (COLD) were also surveyed for the same follow up period. In addition, the differences in clinical findings between those with and without lung cancer were examined. Eight out of 45 patients with IIP (18%) developed lung cancer (adenocarcinoma; 4, small cell carcinoma; 3, squamous cell carcinoma; 2, including one double cancer). All lung cancer patients were male smokers. Looking only at males, 8 out of 37 patients with IIP (21.6%) developed lung cancer. This incidence was significantly higher than that of the male COLD group (2.2%, less than 0.01). In clinical findings, IIP patients with lung cancer had the characteristics of the chronic type of IIP (lack of volume loss on chest radiographic milder dyspnea, not on steroid treatment) when compared with those who did not develop lung cancer.     

Cyclosporin A treatment of interstitial pneumonia]

To assist in making prognoses for patients with interstitial pneumonia (IP) who were treated with cyclosporin A (CsA), we conducted a review of forty-nine patients (32 men and 17 women with a mean age of 62 yrs) with progressive IP during the period from 1997 through 2001. All patients were steroid-resistant or acutely exacerbated cases. They received a low dosage of CsA (100-130 mg/day) combined with corticosteroids. Before and after the CsA therapy, blood gas analysis and HRCT scans were evaluated. Twenty-five patients underwent video-assisted thoracoscopic surgery (VATS) or autopsy for a histopathological evaluation. Among the 49 patients with IP, the documented underlying systemic diseases were of unknown etiology (IPF or IIP) in 26 and were collagen vascular diseases (CVD) in 23. The chest CT pattern and underlying systemic diseases of IP were classified as a usual interstitial pneumonia (UIP) pattern/IPF in 16 cases, a non-UIP pattern/IIP in 10 cases, a UIP pattern/CVD in 7 cases, and a non-UIP pattern/CVD in 16 cases. The prognoses after CsA treatment were improved or unchanged in 27% of cases with a UIP pattern/IPF, 78% of cases with a non-UIP pattern/IIP, 71% of cases with a UIP pattern/CVD and 75% of cases with a non-UIP pattern/CVD; deteriorated in 73%, 22%, 29% and 25% of cases, respectively, with these patterns and underlying diseases. At present, four out of thirteen (31%) patients with acute exacerbation of UIP pattern/IPF have survived for four to twelve months (mean: 7.5 months). Four patients revealed re-exacerbation of IP after the dose of CsA was tapered. Among the 25 patients with IP, the histopathological patterns of IP were classified as usual interstitial pneumonia (UIP) in 10 cases, nonspecific interstitial pneumonia (NSIP) in 14 cases (group I, 2; group II, 5; group III, 7) and diffuse alveolar damage (DAD) in 1 case. The prognoses were improved or unchanged in all cases of NSIP group I, in 80% of cases with NSIP group II, in 29% of cases of NSIP group III and in 20% of cases of UIP; and deteriorated in the case of DAD, in 80% of cases of UIP, in 71% of cases of NSIP group III, and in 20% of cases of NSIP group II. It should be emphasized that CsA combined with corticosteroids may be effective for the treatment of steroid-resistant or acute exacerbation cases of IP. Further studies are required to determine long-term outcome with this treatment.     

Histopathologic variability in usual and nonspecific interstitial pneumonias.

Findings of surgical lung biopsy (SLB) are important in categorizing patients with idiopathic interstitial pneumonia (IIP). We investigated whether histologic variability would be evident in SLB specimens from multiple lobes in patients with IIP. SLBs from 168 patients, 109 of whom had multiple lobes biopsied, were reviewed by three pathologists. A diagnosis was assigned to each lobe. A different diagnosis was found between lobes in 26% of the patients. Patients with usual interstitial pneumonia (UIP) in all lobes were categorized as concordant for UIP (n = 51) and those with UIP in at least one lobe were categorized as discordant for UIP (n = 28). Patients with nonspecific interstitial pneumonia (NSIP) in all lobes were categorized as having fibrotic (n = 25) or cellular NSIP (n = 5). No consistent distribution of lobar histology was noted. Patients concordant for UIP were older (63 +/- 9 [mean +/- SD] yr; p < 0.05 as compared with all other groups) than those discordant for UIP (57 +/- 12 yr) or with fibrotic NSIP (56 +/- 11 yr) or cellular NSIP (50 +/- 9 yr). Semiquantitative high-resolution computed tomography demonstrated a varied profusion of fibrosis (p < 0.05 for all group comparisons), with more fibrosis in concordant UIP (2.13 +/- 0.62) than in discordant UIP (1.42 +/- 0.73), fibrotic NSIP (0.83 +/- 0.58), or cellular NSIP (0.44 +/- 0.42). Survival was better for patients with NSIP than for those in both UIP groups (p < 0.001), although survival in the two UIP groups was comparable (p = 0.16). Lobar histologic variability is frequent in patients with IIP, patients with a histologic pattern of UIP in any lobe should be classified as having UIP.     

Nonspecific interstitial pneumonia (NSIP)

Nonspecific interstitial pneumonia (NSIP) represents one histologic subtype of idiopathic interstitial pneumonia (IIP). NSIP is typified by temporal homogeneity and less profusion of fibroblastic foci than is seen with usual interstitial pneumonia (UIP), the most common IIP. Clinically patients with NSIP present with similar symptoms (cough and dyspnea) when compared to patients with UIP. The duration of these symptoms prior to presentation is variable. The finding of fever may be more common in NSIP and clubbing may be more common in UIP; however, both findings can be seen in either UIP or NSIP. Physiological findings typically demonstrate a restrictive ventilatory defect with decreased gas transfer; little difference exists between UIP and NSIP. High resolution computed tomography (HRCT) scans are more likely to show honeycombing with UIP and a ground-glass pattern with NSIP, however, either of these findings can be seen with UIP or NSIP. The most striking differential feature between NSIP and UIP is the markedly better prognosis for patients with NSIP, a finding that cannot be explained by baseline differences in physiology or radiographic features. In this article we explore the clinical, physiological, and radiographic features of NSIP. We also review available information regarding response to therapy and prognosis.     

Lung function measurement of small airway obstruction in idiopathic interstitial pneumonia

Small airway obstruction in idiopathic interstitial pneumonia was studied in 54 cases of interstitial pneumonia accompanied by restrictive, but not obstructive impairment (%VC less than 80%, FEV1/FVC% greater than 70%). Correlation analysis of %VC showed that small airway obstruction seemed to play a role in the decrease in VC in these cases. Cases were then divided into two groups. In group A, restrictive impairment was caused by the decrease in TLC (%TLC less than 80% & %RV less than 120%) and in group B, it was caused by increase in RV (%TLC greater than 80% & %RV greater than 120). Cases of idiopathic interstitial pneumonia (IIP) were preferentially categorized into group A. Statistical comparison of the lung function measurements revealed that lung parenchyma was altered less severely whereas small airway obstruction was more advanced in group B than group A. Group B was divided into two subgroups, the subgroups of IIP cases and of the other disease cases, and the latter had a larger lung volume and more severely impaired small airway function. Furthermore, IIP cases from group A had less severely altered lung parenchyma than IIP cases from group B. Smoking habits did not seem to be related to these results. The results indicate that in most cases of interstitial pneumonia other than IIP, the lung function was characterized by small airway obstruction rather than decreased lung volume, and some cases of IIP also showed a similar trend. In addition, a long-term study of lung function was made in some cases of interstitial pneumonia and it was shown that small airway obstruction could change in severity after a time interval.     

Steroid treatment based on the findings of transbronchial biopsy in idiopathic interstitial pneumonia.

This study was performed to find the rationale for administering steroids to patients with idiopathic interstitial pneumonia (IIP), which was unlikely to be usual interstitial pneumonia (UIP) but was not surgically biopsied. Among IIP patients in the file of the departments, nine patients who met the following criteria were selected for this study ("non-UIP" group): 1) transbronchial lung biopsy showed dense mononuclear cell infiltration in thickened alveolar septa; 2) chest radiograph and computed tomography showed irregular linear, reticular or ground-glass opacities with alveolar consolidation without honeycombing in the lung base; and 3) spirometry was performed before and after steroid therapy. Ten patients with pathologically confirmed nonspecific interstitial pneumonia ("NSIP" group) were also selected for the comparison. Baseline values and percentage increase of vital capacity (VC) after steroid therapy were plotted. Steroids improved VC in both groups of patients. After 1 yr of steroid therapy, percentage increase of VC in "non-UIP" was 28.8+/-7.7%, which was not significantly different from that in NSIP (30.0+/-11.7%). One "non-UIP" patient and one NSIP patient died after 6.4 and 4.3 yrs of follow-up, respectively. Patients with idiopathic interstitial pneumonia presenting cellular interstitial pneumonia in transbronchial lung biopsy, in addition to radiographic findings not typical for usual interstitial pneumonia, could expect a beneficial effect of steroids without undergoing surgical biopsy.     

Clinical evaluation of idiopathic interstitial pneumonia and interstitial pneumonia associated with collagen vascular disease using logistic regression analysis

OBJECTIVE: To clarify the differences in the clinical features between idiopathic interstitial pneumonia (IIP) and interstitial pneumonia associated with collagen vascular diseases (CVD-IP). METHODS: Symptoms, radiographic findings, pulmonary function, blood chemistry data including autoantibody, and bronchoalveolar lavage fluid (BALF) findings were compared using multiple logistic regression analysis. PATIENTS: The subjects were 44 patients clinically diagnosed with IIP and 33 patients with CVD-IP. RESULTS: The clinical features related to IIP were as follows: male sex, advanced age, past history of hypertension, presence of cough, exertional dyspnea, digital clubbing, an increased level of gamma-globulin, decreased lung volume on chest X-ray, and typical type according to the criteria for IIP on chest X-ray. Increased levels of rheumatoid factor and total cell number in BALF were related to CVD-IP. CONCLUSION: These findings are considered to be useful to differentiate IIP and CVD-IP.     

The role of interleukin-8 in interstitial pneumonia

OBJECTIVE: A variety of inflammatory cells accumulate in the lungs of patients with interstitial lung disease. The potential for IL-8 to be released from these cells into the lungs of patients with idiopathic interstitial pneumonia (IIP), interstitial pneumonia with collagen vascular disease (IP-CVD), sarcoidosis (SAR) and hypersensitivity pneumonitis (HP) was investigated. METHODOLOGY: IL-8 levels were assessed by enzyme-linked immunosorbent assay in BAL fluid and serum, and the expression of IL-8 in the lungs of these patients was evaluated by immunohistochemistry. RESULTS: Serum IL-8 levels were significantly elevated in patients with IIP (P < 0.05) and SAR (P < 0.01). In BAL fluid, the IL-8 level was significantly higher in patients with IIP (P < 0.05), IP-CVD (P < 0.01), SAR (P < 0.01) and HP (P < 0.01). In several cases, IL-8 level correlated with neutrophil density. The IL-8 immunopositive cells were type II pulmonary epithelial cells and alveolar and interstitial macrophages in patients with IIP and IP-CVD. CONCLUSIONS: IL-8 is likely to be a key factor in the pathogenesis of fibrosis of the lung and in lung injury.     

Serum antibody titers against various viruses in idiopathic interstitial pneumonia

As the first step to investigate a possibility that viral infection is involved in the pathogenesis of idiopathic interstitial pneumonia (IIP), serum antibody titers against various viruses were studied in 98 IIP patients. The patients were positive for herpes simplex virus, cytomegalovirus, rubella virus, parainfluenza virus 3, EBV-VCA IgG and adeno virus 1, which were also assessed in 45 normal subjects. As results, IIP patients showed higher titers of EBV-VCA IgG (p less than 0.01). When the frequency of positive populations for each of the 6 viral antibodies was calculated, the values of the frequency in all the 6 viruses were found to be very high in both patients and normal subjects, and there was no significant difference between IIP patients and normal controls. In conclusion, a specific relationship between IIP and a certain viral infection was not observed by studying serum antibody titers against various viruses in IIP patients. It might be worthwhile studying why EBV-VCA IgG titers were shown to be significantly higher in IIP patients than in normals.     

Usual interstitial pneumonia: idiopathic pulmonary fibrosis versus collagen vascular diseases

BACKGROUND: Bronchoalveolar lavage fluid (BALF) lymphocytosis was found in patients with usual interstitial pneumonia (UIP) associated with collagen vascular diseases (CVD) other than diffuse systemic sclerosis (SSc), but it was not found in patients with idiopathic pulmonary fibrosis (IPF), a disease histologically diagnosed as UIP. This difference could be partly due to variations of UIP spectrums between IPF and interstitial pneumonia associated with CVD. METHODS: We scored histopathological findings of lung specimens obtained from 31 cases (16 IPF, 9 CVD other than SSc and 6 SSc) using a semiquantitative scoring method. All cases were diagnosed as UIP by surgical lung biopsy. None of the patients were current smokers. RESULTS: Compared with IPF and SSc cases, CVD patients without SSc presented decreased scores of fibrosis (p < 0.01) and alveolar space cellularity (severity, p < 0.05). Lymphocytes were mainly localized in the alveolar walls and the majority of cells in the alveolar spaces were macrophages. On the other hand, other scores such as cellularity and alveolar wall cell infiltrate did not vary among these three groups. CONCLUSION: Fewer macrophages in the alveolar spaces and a decrease in the degree of fibrosis may contribute to BALF lymphocytosis more in patients with UIP/CVD non-SSc than in patients with IPF/UIP and UIP-SSc.     

非特异性间质性肺炎

非特异性间质性肺炎,是特发性间质性肺炎中继特发性肺间质纤维化后最常见的类型,它在流行病学、发病机制、临床表现、影像学特点、病理表现及预后等方面都有其自身特点,尤其是预后远较特发性肺间质纤维化好。本文将就目前对于NSIP的认识做一综述。     

An electron microscopic study of the pulmonary alveolar capillaries in idiopathic interstitial pneumonia and lungs of collagen vascular diseases]

The ultrastructure of pulmonary alveolar capillaries in idiopathic interstitial pneumonia (IIP) and collagen vascular diseases (CVD) were investigated. In IIP, the endothelial cells were only slightly swollen. The basement membrane (BM) was moderately thickened. In CVD, swelling of the endothelial cells and thickening of the BM were more severe than those of IIP. The injury of the endothelial cells seemed to be more severe than IIP. The patients with PSS and MCTD revealed degeneration of endothelial cells as well as lamellation of BM. The endothelial cell damage was most severe among CVD cases, and these changes were assumed to induce pulmonary hypertension. Microtubular structures were observed in the endothelium of SLE, dermatomyositis, polymyositis, PSS and MCTD patients. Weibel-Palade bodies and increase of pericytes were noticed in PSS and MCTD patients which seemed to be related to endothelial injuries. No electron-dense deposits were observed in any case.     

Bronchoalveolar lavage in idiopathic interstitial lung diseases

Bronchoalveolar lavage (BAL) is useful for diagnosing various interstitial lung diseases (ILDs) and monitoring ILD during treatment. The ability to detect specific agents or substances by using BAL is especially helpful in determining whether idiopathic ILD has a background causality. BAL in combination with other intensive examinations may enable the definitive diagnosis of an idiopathic ILD. Among the idiopathic ILDs of concern, this article focuses on idiopathic interstitial pneumonia (IIP) and cryptogenic organizing pneumonia (COP). IIP and COP are classified together as idiopathic interstitial pneumonia (IIP), an integrated clinicoradiographic pathological disease entity. BAL has identified two points important for differentiating the disease entity: a paucity of lymphocytes appears in the BAL fluid of patients with idiopathic pulmonary fibrosis (IPF), and lymphocytosis with a decreased CD4:CD8 ratio appears in patients with COP. These findings can be useful, in combination with high-resolution computed tomographic (HRCT) data, for selecting a favorable treatment option. On the other hand, these rules cannot be applied to IP associated with collagen vascular disease (CVD). Furthermore, some IIP patients may manifest features of CVD during the clinical course after the detection of IP (interstitial pneumonia). Thus the definite role of BAL cell profiles remains to be determined.     

High-BAL fluid concentrations of RANTES in nonspecific interstitial pneumonia compared with usual interstitial pneumonia

Chemokines such as regulated on activation, normal T-cell expressed and secreted (RANTES), monocyte chemoattractant protein (MCP)-1, monocyte inflammatory protein (MIP)-lalpha have been reported to play an important role in the pathogenesis of interstitial lung diseases. Among idiopathic interstitial pneumonia (IIP), nonspecific interstitial pneumonia (NSIP) has elevated percentages of Lymphocytes in bronchoalveolar lavage (BAL) fluid compared with usual interstitial pneumonia (UIP). These chemokines are candidate mediators for lymphocyte attraction to the lung in NSIR Therefore, we measured the BAL fluid levels of RANTES, MCP-1 and MIP1-alpha in 15 patients with idiopathic NSIP, 20 with idiopathic UIP, 22 with sarcoidosis and 12 healthy volunteers to evaluate the contribution of these chemokines using enzyme-linked immunosorbent assays. The levels of RANTES in BAL fluid were significantly higher in patients with NSIP compared with healthy volunteers (P < 0.01), UIP and sarcoidosis (P < 0.05). In MCP-1, the levels in BAL fluid of NSIP and UIP patients were significantly elevated compared with healthy volunteers and sarcoidosis patients (P < 0.01). These results suggest that RANTES and MCP-1 in BAL fluid may play an important role in inflammatory cell recruitment to the lung in idiopathic NSIP as well as other interstitial lung diseases.     

Comparison of bronchoalveolar lavage fluids from nonspecific interstitial pneumonia and from ordinary interstitial pneumonia]

We studied cell findings in the bronchoalveolar lavage fluid (BALF) of 13 patients with nonspecific interstitial pneumonia (NSIP) and 20 with ordinary interstitial pneumonia (UIP). NSIP and UIP were difficult to distinguish by high-resolution CT. Surgical lung biopsies were performed in all patients. We divided the patients with NSIP and UIP into 4 groups, a group of idiopathic NSIP (idiopathic NSIP), a group of NSIP patients associated with collagen vascular disease (CVD NSIP), a group of idiopathic UIP patients (idiopathic UIP) and a group of UIP patients associated with collagen vascular disease (CVD UIP). We then examined the differences in BALF cell findings between these groups. The percentage of lymphocytes in BALF was higher in idiopathic NSIP and CVD NSIP than in the healthy control. The percentage of alveolar macrophages was lower and the percentage of lymphocytes was higher in CVD NSIP than in idiopathic UIP. The CD4/CD8 ratio in BALF of idiopathic NSIP was lower than with idiopathic UIP. It is important that NSIP be distinguished from UIP clinically, and our results suggest that BALF cell findings may be useful for making this distinction.     

Classification and recent advances in idiopathic interstitial pneumonia

Idiopathic interstitial pneumonia (IIP) is a heterogeneous group of diseases comprising acute interstitial pneumonia, bronchiolitis obliterans organizing pneumonia (BOOP), nonspecific interstitial pneumonia, desquamative interstitial pneumonia, and idiopathic pulmonary fibrosis and usual interstitial pneumonia (IPF/UIP). We review the clinicopathological spectrum of IIP and introduce recent advances in classification, treatment, and prognosis. BOOP can be clinically categorized as an interstitial pneumonia, though prominent granulation tufts are seen in the airspaces. Though differences between the nonspecific interstitial pneumonia and other lips can be histopathologically clarified, the focus of clinical research on NSIP is differentiation from BOOP, or from IPF and UIP. IIP can be categorized into two groups: groups with acute or subacute lung injuries or fibrosis, such as in acute interstitial pneumonia, BOOP and nonspecific interstitial pneumonia, and groups with chronic injuries or fibrosis, such as IPF/UIP. This classification accords well with the maturity of fibrosis, CT findings, bronchoalveolar lavage fluid cell findings, and prognosis. The most critical problem is the treatment of IPF/UIP, because of its high mortality.     

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.     

Cyclosporin treatment in steroid-resistant and acutely exacerbated interstitial pneumonia

OBJECTIVE: The aim of this study was to evaluate the efficacy of cyclosporin A (CsA) in patients with interstitial pneumonia (IP). DESIGN: Retrospective comparative study. PATIENTS: We reviewed 33 patients (23 males and 10 females with a mean age of 62.5 years) with histologically-proven progressive IP who were treated with CsA. All patients had corticosteroid-resistant IP or developed acute exacerbation of IP in their courses. RESULTS: The underlying systemic diseases were: idiopathic interstitial pneumonias (IIPs) in 19 patients, and collagen vascular diseases (CVDs) in 14. The histopathological patterns and underlying diseases of IP were classified as usual interstitial pneumonia (UIP)/idiopathic pulmonary fibrosis (IPF) in 10 patients, cellular-nonspecific interstitial pneumonia (NSIP)/IIPs in 3, fibrotic-NSIP/IIPs in 5, organizing pneumonia (OP)/IIP in 1, UIP/CVDs in 4, cellular-NSIP/CVDs in 7, fibrotic-NSIP/CVDs in 2, and diffuse alveolar damage (DAD)/CVD in 1, respectively. They received a low dosage of CsA combined with corticosteroids. The prognoses after treatment with CsA were well correlated with histopathological patterns. Cellular-NSIP and OP showed better prognoses than fibrotic-NSIP, UIP or DAD. In addition, CVDs had better prognoses than IIPs, when compared on the basis of the same histopathological patterns. Furthermore, the prognoses in the CsA-treated group were significantly better than in those without CsA treatment in regard to acute exacerbation of UIP/IPF. CONCLUSIONS: CsA combined with corticosteroids may be an efficacious treatment for corticosteroid-resistant IP and for acute exacerbation of IPF.