Selection of Oral Antifungals for Initial Maintenance Therapy in Chronic Pulmonary Aspergillosis: A Longitudinal Analysis.

BACKGROUND: There are limited data for direct comparisons of the efficacy of oral itraconazole (ITCZ) and oral voriconazole (VRCZ) therapy in the treatment of chronic pulmonary aspergillosis (CPA). METHODS: We conducted a retrospective, follow-up, observational study of CPA patients enrolled in 2 previous multicenter trials. RESULTS: Of the 273 CPA patients, 59 and 101 patients started maintenance therapy with oral ITCZ and oral VRCZ, respectively, just after the end of acute intravenous therapy in each trial. At the end of the observation period in this follow-up study (median observation period, 731 days), the percentage of patients who showed improvement was lower in the ITCZ group than in the VRCZ group (18.2% vs 40.0%). However, after including stable patients, the percentages were 50.9% and 52.6%, respectively, in the ITCZ and VRCZ groups, which were not significantly different (P = .652). Multivariable Cox regression analysis showed no significant influence of the choice of initial maintenance treatment (ITCZ or VRCZ) on overall mortality as well as CPA-associated mortality. Multivariable logistic regression showed that oral ITCZ selection for initial maintenance therapy was an independent risk factor for hospital readmission and switching to other antifungal agents (odds ratio [OR], 3.1; 95% confidence interval [CI], 1.3-7.5 and OR, 5.7; 95% CI, 2.0-15.7, respectively). CONCLUSIONS: Oral VRCZ for initial maintenance therapy showed better effectiveness than oral ITCZ for clinical improvement in CPA patients. There was no difference in crude mortality between initial maintenance therapy with VRCZ and ITCZ, especially in elderly CPA patients. CLINICAL TRIALS REGISTRATION: UMIN000007055.

An autopsy study of combined pulmonary fibrosis and emphysema: correlations among clinical, radiological, and pathological features.

BACKGROUND: Clinical evaluation to differentiate the characteristic features of pulmonary fibrosis and emphysema is often difficult in patients with combined pulmonary fibrosis and emphysema (CPFE), but diagnosis of pulmonary fibrosis is important for evaluating treatment options and the risk of acute exacerbation of interstitial pneumonia of such patients. As far as we know, it is the first report describing a correlation among clinical, radiological, and whole-lung pathological features in an autopsy cases of CPFE patients. METHODS: Experts retrospectively reviewed the clinical charts and examined chest computed tomography (CT) images and pathological findings of an autopsy series of 22 CPFE patients, and compared these with findings from 8 idiopathic pulmonary fibrosis (IPF) patients and 17 emphysema-alone patients. RESULTS: All patients had a history of heavy smoking. Forced expiratory volume in 1 s/forced vital capacity (FEV1/FVC%) was significantly lower in the emphysema-alone group than the CPFE and IPF-alone groups. The percent predicted diffusing capacity of the lung for carbon monoxide (DLCO%) was significantly lower in the CPFE group than the IPF- and emphysema-alone groups. Usual interstitial pneumonia (UIP) pattern was observed radiologically in 15 (68.2%) CPFE and 8 (100%) IPF-alone patients and was pathologically observed in all patients from both groups. Pathologically thick-cystic lesions involving one or more acini with dense wall fibrosis and occasional fibroblastic foci surrounded by honeycombing and normal alveoli were confirmed by post-mortem observation as thick-walled cystic lesions (TWCLs). Emphysematous destruction and enlargement of membranous and respiratory bronchioles with fibrosis were observed in the TWCLs. The cystic lesions were always larger than the cysts of honeycombing. The prevalence of both radiological and pathological TWCLs was 72.7% among CPFE patients, but no such lesions were observed in patients with IPF or emphysema alone (p=0.001). The extent of emphysema in CPFE patients with TWCLs was greater than that in patients without such lesions. Honeycombing with emphysema was also observed in 11 CPFE patients. CONCLUSIONS: TWCLs were only observed in the CPFE patients. They were classified as lesions with coexistent fibrosing interstitial pneumonia and emphysema, and should be considered an important pathological and radiological feature of CPFE.

Diagnostic performance of interferon-gamma release assays in elderly populations in comparison with younger populations.

An understanding of the diagnostic performance of interferon-gamma release assays (in terms of parameters such as specificity, positive predictive value, and likelihood ratio) is important in the diagnosis of active tuberculosis in elderly Japanese patients because the high proportion of a prior history of tuberculosis among these patients can lead to misleading results. To elucidate the diagnostic performance of such assays, we examined the results of the QuantiFERON-TB Gold In-Tube test (QFT-GIT) in 65 patients in a younger group, and 52 patients in an elderly group who were suspected of having active tuberculosis and who had received the QFT-GIT. The median ages of the younger patients and elderly patients were 54 and 78 years, respectively. Among patients with active tuberculosis, the number of those with positive results on the QFT-GIT was similar in the two age groups [15 out of 17 (88.2 %) in the younger patients compared with 7 out of 8 (87.5 %) in the elderly patients]. However, in the patients with other diseases the number of those with positive QFT-GIT results was significantly different in the younger and elderly groups, being 6.3 and 27.3 %, respectively (P = 0.01). Although the sensitivity, negative predictive value, and negative likelihood ratio were similar in the two groups, the specificity, positive predictive value, and positive likelihood ratio were significantly lower in the elderly patients, being 72.7% (95 % confidence interval [CI], 57.2-85.0) compared with 93.8% (95 % CI, 82.8-98.7), 36.8% (95 % CI, 16.3-61.6) compared with 83.8% (95 % CI, 58.6-96.4), and 3.21 (95 % CI, 1.85-5.56) compared with 14.12 (95 % CI, 4.66-42.81), respectively. In the elderly patients with positive results on the test, a comparison of clinical data between those with active tuberculosis and those with other diseases demonstrated that the only clinical parameter showing a significant difference between these two groups was the radiological finding of small nodules in the patients with active tuberculosis (P < 0.01). The QFT-GIT may be less accurate in elderly patients, and radiological findings can be helpful in the clinical evaluation of patients with positive results on the test.

Histopathological implications of Aspergillus infection in lung.

This paper opens with a discussion on the significance of invasive fungal infections in advanced contemporary medicine, with an emphasis on the intractability of disease management and the difficulties of diagnosis. This is followed by a discussion concerning classification, histopathological features, and pathophysiology. While it has been largely accepted that Aspergillus species is recognized by cellular receptors and attacked by neutrophils, the radiological and macroscopic findings linking infection with neutropenia remain unconfirmed. In an effort to gain a better understanding of the pathophysiology and pathogenesis of invasive aspergillosis, we wish to emphasize the utility of radiological and histopathological examinations since these can provide detailed information on the extremely complex interaction between the causative microbes and tissue responses. A review of noninvasive or semi-invasive aspergillosis is also provided, with particular emphasis on chronic necrotizing pulmonary aspergillosis, which is recognized as a transition form of simple pulmonary aspergilloma and invasive pulmonary aspergillosis, although few findings have been reported in this area.

Pathological differentiation of chronic hypersensitivity pneumonitis from idiopathic pulmonary fibrosis/usual interstitial pneumonia.

AIMS: To evaluate the histological characteristics differentiating chronic hypersensitivity pneumonitis (chronic HP) with a usual interstitial pneumonia (UIP)-like pattern from idiopathic pulmonary fibrosis (IPF)/UIP. METHODS AND RESULTS: Surgical lung biopsy specimens from 22 patients with chronic HP diagnosed as having a UIP-like pattern upon histological examination and 13 patients with IPF/UIP were examined and the incidences of bronchiolitis, perilobular fibrosis, centrilobular fibrosis, bridging fibrosis, organizing pneumonia, fibroblastic foci, honeycombing, granulomas, giant cells, lymphocytic alveolitis and lymphoid follicles were compared. Bronchiolitis, centrilobular fibrosis, bridging fibrosis, organizing pneumonia, granulomas, giant cells and lymphocytic alveolitis were significantly more frequent among patients with chronic HP than among patients with IPF (all P<0.01). CONCLUSIONS: Centrilobular fibrosis, bridging fibrosis and organizing pneumonia, in addition to bronchiolitis, granulomas and giant cells, are characteristic features of chronic HP with a UIP-like pattern. These features are therefore important in differentiating chronic HP from IPF/UIP, as management strategies differ for the two disorders.

Efficacy and safety of short- and long-term treatment of itraconazole on chronic necrotizing pulmonary aspergillosis in multicenter study.

In the respiratory field, chronic pulmonary aspergillosis, such as chronic necrotizing pulmonary aspergillosis (CNPA) or aspergilloma, is important. We examined the efficacy and safety of short- and long-term itraconazole (ITCZ) administration, involving a switch from injection to an oral preparation, in patients with CNPA. In all hospitals participating in this study, the protocol was approved by the ethics review board. This study started after UMIN registration (UMIN000001727). Subjects enrolled in this study were patients who were clinically or definitively diagnosed with CNPA in the respiratory field, according to the diagnostic criteria of the Japanese "Guidelines for management of deep-seated mycosis 2007," in 16 hospitals that participated in this study between May 2008 and March 2011. Treatment was started with ITCZ injection. Subsequently, the agent was switched to an oral preparation. Efficacy was evaluated with major items (clinical symptoms, fever, imaging findings) and minor items (nutritional status, inflammatory markers). Twenty-nine patients were enrolled; safety was evaluated in 24 and efficacy in 23. Of the 23 patients, 10 (43.5 %) responded. With respect to the administration period, the response rates in 8 patients treated for a short period and 15 treated for a long period were 25.0 % and 53.3 %, respectively. Trough blood concentration of ITCZ reached a level at which ITCZ may be effective for aspergillosis at 3 days after the start of ITCZ injection therapy. After changing to high-dose capsules, its level was also maintained. Adverse events such as liver dysfunction and heart failure were observed in 9 of the 24 patients. Furthermore, 6 patients died. However, there was no relationship between these events and ITCZ. Step-down therapy from ITCZ injection to oral administration may be a useful treatment option in CNPA patients requiring long-term treatment.

[Two cases of microscopic polyangitis with preceding interstitial pneumonia diagnosed by surgical lung biopsy].

We encountered 2 cases of microscopic polyangitis (MPA) with preceding interstitial pneumonia. The patients were elderly men, and radiological findings showed a UIP pattern in both cases. Furthermore, ANCA-associated vasculitis had been suspected since the first admission in case 1, because MPO-ANCA tests were positive, and the surgical lung biopsy revealed vasculitis in a honeycomb lesion. A diagnosis of idiopathic pulmonary fibrosis was made in case 2 because no findings of vasculitis were pathologically confirmed, and MPO-ANCA was not examined. Both patients were followed up without any treatment, but steroid therapy with immunosuppressants was initiated after a diagnosis of MPA was made from a renal failure complication. Remission continued in case 1, but patient 2 died due to a pulmonary hemorrhage complication, despite some temporary improvements. An autopsy revealed massive alveolar hemorrhage and neutrophil infiltration in the alveolar walls that suggested pulmonary capillaritis, in spite of the absence of pathological evidence, which was not detected in the honeycomb lesions. These 2 cases indicate that MPO-ANCA should be examined in the follow-up of chronic interstitial pneumonia. Furthermore, it should be assumed that the size of involved blood vessels, their distribution and the timing of occurrence may be different in individual case of ANCA-associated interstitial pneumonia.

[A study on clinical features of Mycobacterium kansasii pulmonary disease in women].

OBJECTIVES: To clarify clinical features of M. kansasii pulmonary disease in women. METHODS: We performed a retrospective analysis of M. kansasii pulmonary disease in women compairing with that in men. We focused on 8 female cases of M. kansasii pulmonary disease during the past 7 years from June 1998 to August 2005. RESULTS: The cases of M. kansasii pulmonary disease in women have increased in the latter few years. The mean age of female cases was higher than that of male cases, 65.6 and 53.1 years old, respectively. The number of female cases with smoking history was lower than that of male cases, 37.5% and 90.0%, respectively. Two female cases had underlying pulmonary diseases, as compared with 10 male cases, 25.0% and 33.3%, respectively. The radiological findings in female cases included 2 cavitary opacities, 1 infiltrative opacity and 5 nodular, bronchiectatic opacities, as compared with 27 cavitary opacities, 1 infiltrative opacity, 1 solitary nodular opacity and 1 nodular, bronchiectatic opacity in male cases. MAC was also detected in 2 female cases, who presented with nodular, bronchiectatic opacities. On the other hand, there were 6 female cases, in which no other NTM was detected. 3 cases showed cavitary or infiltrative opacities, which improved with the following 3 tuberculous drugs INH, RFP, and EB (HRE), while others showed nodular, bronchiectatic opacities, in which 2 cases showed radiological exacerbations without any treatment and another one revealed an improvement with HRE. CONCLUSIONS: M. kansasii pulmonary disease in women tends to be identified in elderly who smoke less and have no underlying pulmonary diseases, and most of radiological findings in female cases revealed nodular, bronchiectatic opacities. Summing up all these findings, clinical features of M. kansasii pulmonary disease in women was considered to resemble that of MAC infection, and it was speculated that the increase of M. kansasii pulmonary disease in women has some relationship with that of MAC infection in middle or lingular lobe. However, it was confirmed that some cases of M. kansasii pulmonary disease in women might primarily present with nodular, bronchiectatic lesions, regardless of MAC infection.

[Clinical comparison of male and female patients with pulmonary disease caused by Mycobacterium avium complex (P-MAC)].

OBJECTIVES: The objective of this study was to clarify clinical feature of Pulmonary Mycobacterium avium complex disease (P-MAC). METHOD: The present study was performed in 120 patients with P-MAC diagnosed during the period from January 2000 to March 2007. We divided P-MAC patients into four groups by the clinical disease type and gender, and retrospectively examined the clinical characteristics. RESULTS: The subjects were 15 male (NB-M) and 71 female (NB-F) patients with nodular bronchiectatic disease (NB), and 24 male (FC-M) and 10 female (FC-F) patients with fibrocavitary disease (FC). The average age was lowest in the NB-F group (58.0 yrs), and highest in the FC-M group (65.8 yrs). There were 17 patients in the FC-M group and only two patients in the FC-F group with a history of smoking. The average body mass index (BMI) was 16.9, with the lowest value in the FC-F group. In the FC-M group, most of the patients had underlying pulmonary disease, whereas in the FC-F group, only four patients had underlying old pulmonary tuberculosis. The average anterior-posterior dimension was 75.2 mm, being lowest in the FC-F group, and more than 90 mm in the other groups. The proportion of refractory cases was lowest in the NB-M group. CONCLUSION: We thought that we were able to clarify characteristics of patients with disease caused by MAC by analyzing the types of the disease separately in men and women.

[Evaluation of KL-6 CLEIA reagent].

KL-6 is a high-molecular-weight sialylated glycoprotein, classified as a cluster 9 pulmonary cell antigens, and is a sensitive marker for the clinical diagnosis of interstitial pneumonia and its activity, especially in the acute phase. Additionally, it is necessary to diagnosis that patient was not pneumothirax, pulmonary thromboembolism and heart failure. In this study, we evaluated a new assay system based on chemiluminescence EIA (CLEIA) on a fully automated analyzer. Both plasma and serum samples were used, and the master calibration method was applied, eliminating the need for a standard curve preparation. The assay time was shortened to less than 1 hour. Good correlations were observed between this assay and conventional assay kits, y = 1.094x-6.849, r = 0.986 using 326 samples, and between serum and plasma y = 0.997x-1.211, r = 0.997 using 225 paired samples. In addition, the alteration of KL-6 concentration in patients undergoing chemotherapy treatment resulted in similar results that with conventional kits, and elevated KL-6 concentrations were observed in samples from patients with interstitial pneumonia. These results underscore the usefulness of this new assay kit as a rapid test, particularly for the medical examination of outpatients and the treatment of emergency cases in the acute phase of interstitial pneumonia.

[Case of acute bird fancier's lung caused by a yellow-shouldered Amazon bird associated with lung cancer].

A 69-year-old man was admitted to our hospital complaining of generalized weakness and cough for one month. Chest computed tomography (CT) demonstrated bilateral ground-glass opacities and a nodule in right S6 about 11mm in diameter with multiple mediastinal lymph node swellings. After admission the patient's symptoms improved without therapy and examination of the bronchoalveolar lavage fluid (BALF) and transbronchial lung biopsy (TBLB) revealed findings compatible with acute hypersensitivity pneumonitis. We did not consider that the acute hypersensitivity was caused by the patient's Amazon bird, because he had been breeding them for 40 years. However after obtaining a careful history, it became clear that close and frequent contact with the bird had occurred for the first time in the previous year. On the basis of the anti-bird excreta antibody found in the patient's serum and BALF, we diagnosed this case as a case of acute bird fancier's lung caused by the yellow-shouldered Amazon bird. We diagnosed the nodule in right S6 as lung adenocarcinoma by a thoracoscopic lung biopsy, and performed lower lobe lobectomy. We considered that the mediastinal lymph node swellings were caused by hypersensitivity pneumonitis.

[Aspergillosis].

Aspergillosis occurs as an opportunistic infection, and is known as the disease whose diagnosis and treatment are particularly difficult. Japan's first guidelines for the diagnosis and management of invasive fungal infection were revised in 2007, and it is expected that the guidelines may encourage the standardization of the management of fungal infection. The algorithm of the guidelines is composed of three categories of diagnosis: "Proven infection", "Clinically documented infection or Probable infection" and "Possible infection"; and 2 categories of therapy: "empiric", and "targeting" therapy. The early diagnosis and establishment of treatment methods for, pulmonary aspergillosis, neither of which are adequate presently, are a pressing need. However, the recent development of several serological diagnostic methods and launching new antifungal drugs changes the diagnosis and therapeutic strategy for pulmonary aspergillosis.

Catalases of Aspergillus fumigatus and inflammation in aspergillosis.

The article describes various features of aspergillosis and a discussed the role of calatases produced by Aspergillus fumigatus during infection. Since a large body of invasive Aspergillus infection occurs as an opportunistic infection in variously impaired defense mechanisms, there is a wide spectrum of histopathological features of lesions demonstrated at the site of infection. Accordingly, histopathology of the lesions can be understood as a phenotypical representation of interaction between differently impaired functions of neutrophils and macrophages and virulence factors of invading Aspergilli. Consideration of previous pathological knowledge regarding infection and inflammation provides much important information to predict the pathophysiology of a patient. Meanwhile, detoxification of hydrogen peroxide by catalases has been proposed as a way to overcome this host response. A. fumigatus produces three active catalases, one from conidia and two from mycelia. CatAp, a spore specific monofunctional catalase, is resistant to heat and metal ions. In spite of their increased sensitivity to H(2)O(2), killing of catA conidia by alveolar macrophages, virulence in animals was similar to wild type conidia. In contrast to mycelial Cat1p, and CatAp catalases, the mycelial Cat2p is a bifunctional catalase-peroxidase enzyme and is also sensitive to heat, metal ions and detergent. Surprisingly, the mycelium of the double cat1 cat2 mutant with no catalase activity has only a slightly increased sensitivity to H(2)O(2) and was as sensitive to the killing of polymorphonuclear neutrophils as the wild type strain. However, it showed a delayed infection in the rat model of aspergillosis compared to the wild type strain. Consequently, it should be emphasized that conidial catalase is not a virulence factor but that mycelial catalases transiently protect the fungus from the host defence reactions.

[A case of eosinophilic bronchiolitis complicated with eosinophilic sinusitis].

A 42-year-old man was admitted to our hospital, complaining of dyspnea and cough for six months. Chest CT demonstrated thickening of the bronchial walls and some centrilobular nodules. From the laboratory data and the clinical course, he was first suspected to have bronchial asthma. However, it was necessary to rule out bronchiolitis due to other causes, because he had no previous asthma history and also because of the CT findings. We performed surgical lung biopsy to make a definite diagnosis. The pathological findings revealed eosinophilic bronchiolitis. While dyspnea and the eosinophilic nasal polyp improved by treatment with oral steroid therapy, the eosionophilic sinusitis and bronchiolitis relapsed after steroid tapering. Improvement and relapse of nasal and lower airway symptoms were synchronously observed. Eosinophilic bronchiolitis and eosionophilic sinusitis in this case may be considered to be a category of airway eosinophilic inflammation.

[A case of volcanic ash lung: report of a case].

A 57-year-old woman inhaled much volcanic ash without using a mask every day during the eruption of the Miyake Volcano in August 2000. An abnormal shadow was pointed out on her chest radiography by chance, after she sought refuge in Higashimurayama city in September. She had no respiratory symptoms and her chest radiography in an annual health check in July 2000 had showed no abnormality. She was admitted to our hospital and thoracoscopic lung biopsy was performed. We diagnosed it as lung inflammation caused by volcanic ash. The reasons for diagnosis were because the abnormal shadow appeared after the inhalation of volcanic ash, chest computed tomography showed diffuse irregular shadows with air bronchogram, thoracoscopic lung biopsy showed cellular-bronchiolitis around crystals, and the results of mineralogical analysis of the particles in alveolar macrophages detected in the biopsy specimen by scanning electron microscopy (SEM) were very similar to those of volcanic ash. The shadow on her chest radiography disappeared gradually without any treatment, but she avoided further exposure to volcanic ash. It is necessary to consider volcanic ash capable of causing lung inflammation.

Pathophysiological Implication of Computed Tomography Images of Chronic Pulmonary Aspergillosis.

Chronic pulmonary aspergillosis (CPA) is a refractory disorder that needs long-term antifungal treatment and occasionally results in fatal respiratory failure and hemoptysis. However, the pathological features of the disorder have not been thoroughly delineated. Thirty cases were therefore analyzed clinically and histologically to elucidate the pathophysiology of CPA. The subjects comprised 14 individuals who underwent surgical removal and 16 patients who died. No subject exhibited a severely immunocompromised state. The main symptoms included cough, hemosputum, and dyspnea. Chest computed tomography (CT) findings revealed a cavity, fungus ball, and consolidation and/or ground glass opacity (GGO); 27 serial CT scans showed enlarged consolidation and/or GGO (70%), dilatation of the cavity (26%), and extension to the opposite lung (22%). Histopathological findings revealed a cavity with ulceration, bronchitis, and various degrees of organizing pneumonia (OP) that were correlated with the area of consolidation and GGO on the CT scan. The essential pathophysiology of CPA can be understood as an active state of ulceration of the cavity and/or erosive bronchitis caused by contact with the fungus ball, which may play a significant role in the development of OP. Consequently, OP is thought to reflect respiratory failure that relates to the prognosis of CPA.

Sarcoid Myositis with Anti-Ku Antibody Consistent with both Sarcoidosis and Polymyositis.

We herein describe a case of sarcoid myositis with anti-Ku antibody positivity. Pathological findings of the muscle were compatible with sarcoidosis, but could not be completely distinguished from myositis diseases that arise from other causes. According to a physical examination, pathological findings, the detection of anti-Ku antibody and the human leukocyte antigen (HLA)-DPB1 allele, we strongly suspected that the patient developed both sarcoidosis and polymyositis. Sarcoidosis is often complicated by autoimmune diseases. This case suggests the possibility that sarcoidosis and other autoimmune diseases may have common causal genetic factors.

Histological study of chronic pulmonary aspergillosis.

BACKGROUND: Chronic pulmonary aspergillosis (CPA) has been accepted the criteria for the diagnosis of pulmonary Aspergillus infection. Whereas, either pathophysiology or signs of CPA remains still controversial. METHODS: In this study, we histopathologically investigated 25 specimens of CPA, surgically resected. RESULTS: 21 (84 %) of that comprised male. There were 21 cases with mild impairment of the immune system and/or a scar mostly due to old tuberculosis. There is a tendency for a negative correlation between peripheral blood white cell numbers and value level of beta-(1,3)-D-glucan. Four cases showed a granular fluorescent signal in granulation tissue surrounding the cavity without the fungal aspects itself. CONCLUSIONS: In conclusion, acute inflammatory exudate along the terminal respiratory tract is most significant pathophysiolocial complication of the CPA, caused to organizing pneumonia, which derives fatal respiratory failure. In addition, the viability of fungus does not concern extension of exudative inflammation at the site of erosion along terminal airway.

Hyperplastic epithelial foci in honeycomb lesions in idiopathic pulmonary fibrosis.

Seventy-two cases of idiopathic pulmonary fibrosis (IPF) were examined from 2856 consecutive autopsy cases at the Japanese Red Cross Medical Center in Tokyo from 1973-1996. Primary lung cancer had arisen in 31 of 72 cases of IPF (43%), significantly higher than the incidence in cases without IPF (8.1%) and in the cases with non-IPF chronic lung diseases (11.9%). Hyperplastic epithelial foci in the honeycomb lesions of IPF cases were significantly more prominent in the lower than in the upper lobe, in cases with or without lung cancer, and they were more prominent in the lower lobe of IPF with than in those without cancer. The length of hyperplastic epithelial foci in the lower lobe of IPF cases was longer than that in interstitial pneumonia-associated with collagen vascular diseases. There was a higher PCNA labeling index of hyperplastic epithelial foci in IPF cases than in cases of interstitial pneumonia-associated with collagen vascular diseases. The PCNA labeling index was almost the same between smokers and nonsmokers with IPF. Overexpression of p53 was observed in hyperplastic epithelial foci in honeycomb lesion of IPF. DNA ploidy analysis of hyperplastic epithelial foci in the paraffin sections of 12 IPF cases revealed aneuploidy patterns in eight cases. These results strongly suggest that accelerated cell proliferation occurs in the honeycomb lesion of IPF, and that regenerative epithelia becomes susceptible to carcinogenic agents in addition to the smoking effect.

Phenotype of regenerative epithelium in idiopathic interstitial pneumonias.

The epithelial alteration in interstitial pneumonias is one of the repair processes at the sites of disease activity. Regenerative epithelial cells may participate in remodeling of the lung. To determine the phenotype of regenerative epithelial cells in usual interstitial pneumonia (UIP) and nonspecific interstitial pneumonia (NSIP), the expression of Clara cell 10KD protein (CC10), cytokeratin (CK) 14 and 17, surfactant apoprotein (SP)-A, KL-6/MUC1, transforming growth factor (TGF) beta2 were examined in 25 patients with UIP, 9 patients with NSIP and normal lung tissues from 10 patients with lung cancer. In honeycomb lesions of UIP, non-ciliated columnar cells mainly expressed CC10, cuboidal cells expressed CC10, CK17, CK14 and SP-A in descending order. Fibroblastic foci are covered by CK17, CK14, CC10, and a few SP-A positive flattened or cuboidal cells. Regenerative epithelium in NSIP mainly comprised cuboidal cells expressing SP-A, CC10 and CK17. KL-6 was more remarkably expressed in cuboidal and non-ciliated columnar cells both in UIP and NSIP. Expression of TGFbeta2 was observed in cuboidal and flattened epithelium. In severe fibrotic areas, CC10 expressing cells were more prominent, while SP-A positive cells were more prominent in less fibrotic areas. Regenerative epithelial cells in remodeling area in UIP may be derived from bronchiolar basal cells and Clara cells, while most of those in NSIP may be derived from type II pneumocytes. The different origin of regenerative epithelium may reflect the severity and extent of the injury and the degree of consequent fibrosis in UIP and NSIP.