Prospective study of the value of transbronchial lung biopsy after lung transplantation

Transbronchial lung biopsy (TBB) has become the gold standard for the diagnosis of acute rejection and cytomegalovirus (CMV) pneumonia in lung transplant recipients. The aim of this study was to assess the value of regular surveillance TBB in stable asymptomatic patients and to establish the role of TBB as a follow-up procedure 1 month after a previous pathological biopsy result. We prospectively evaluated 76 TBBs performed in 17 lung transplant recipients. A definite pathological results was found in 14 of 15 TBBs performed for clinical indications: CMV pneumonia (5), acute rejection grade > or = A2 according to the criteria of the International Society for Heart and Lung Transplantation (ISHLT) (4), bronchiolitis obliterans (3), and desquamative interstitial pneumonitis (2). Fifteen of 45 surveillance TBBs performed in asymptomatic patients revealed significant abnormalities. Ten episodes of acute rejection ISHLT grade > or = A2 and three episodes of CMV pneumonia detected by TBB had direct therapeutic consequences. Nine of 16 follow-up TBBs performed 1 month after a pathological biopsy result again showed relevant pathological findings. With the exception of one severe haemorrhage, no life-threatening complications occurred. Our results suggest that transbronchial lung biopsies performed on a regular basis after lung transplantation are important for the detection of asymptomatic and/or persistent acute rejection or injection. In the long-term, this strategy might be the most effective tool in reducing the incidence of bronchiolitis obliterans, which is still the main obstacle for further improvement of long-term survival after lung transplantation.     

The sensitivity of transbronchial biopsy for the diagnosis of acute lung rejection

Transbronchial biopsy has become the procedure of choice for the diagnosis of acute lung rejection after transplantation, but the sensitivity of the technique in this setting remains unknown. In this study, 14 mongrel dogs underwent left lung transplantation, after which triple-drug immunosuppression was given for 5 days and then all immunosuppression was stopped. All animals had clear chest radiographs at this time. Transbronchial biopsy was performed in nine lung regions (two to six pieces of lung tissue were obtained per region, with a mean of 4.3 pieces per region) before the animals were killed 2 to 4 days later, at which time varying degrees of rejection had occurred. Rejection was graded histologically on a scale of 0 to 3 (0 = no rejection, 1 = mild rejection, 2 = moderate rejection, 3 = severe rejection) in each piece of lung tissue obtained at transbronchial biopsy. After the dogs were put to death, the true state of lung rejection was determined by histologic examination of the entire lung. We calculated the sensitivity of transbronchial biopsy with 95% confidence intervals. Five pieces of lung tissue were needed to yield a sensitivity of 92% (82%, 100%) to identify mild rejection in the entire lung with transbronchial biopsy. Three pieces of lung tissue were needed to yield a sensitivity of 92% (84%, 100%) to identify the presence of moderate to severe rejection in the entire lung (that is, rejection that requires pulse therapy) on transbronchial biopsy. These results indicate that three to five pieces of lung tissue that are suitable for diagnostic purposes obtained at transbronchial biopsy are adequate for the diagnosis of acute pulmonary rejection after lung transplantation.     

Adhesion molecules (E-selectin and ICAM-1) in pulmonary allograft rejection

Vascular endothelial cells act as antigen-presenting cells in the lung allograft and stimulate alloreactive host lymphocytes. Activated lymphocytes and cytokines can induce expression of leukocyte-endothelial adhesion molecules that facilitate invasion of the allograft by circulating leukocytes. To define the role of endothelial HLA class II antigen and adhesion molecule expression in lung allograft rejection, we prospectively analyzed endothelial expression of HLA class II, E-selectin, and intercellular adhesion molecule-1 (ICAM-1) antigens in 52 transbronchial biopsy specimens from 24 lung allograft recipients as compared to normal control subjects. Thirty-one of 52 specimens showed histologic rejection and 8 of 24 patients developed histologic obliterative bronchiolitis (OB) by the end of the study period. Increased expression of HLA class II antigen was seen in 32 of 52 (62%) lung allograft specimens, but increased expression did not correlate with acute rejection or OB. In contrast, E-selectin expression was seen in 30 of 52 (58%) biopsy specimens and was associated with acute rejection (p < 0.005) and with the development of OB (p < 0.05). Increased expression of ICAM-1 was seen in only 18 of 52 (35%) biopsy specimens and did not correlate with acute rejection or OB. These data suggest that E-selectin expression may be a tissue marker of acute and chronic lung rejection possibly by promoting leukocyte adhesion to the allograft endothelium. The high levels of endothelial HLA class II expression may reflect long-term antigenic stimulation of the allograft even in the absence of rejection.     

Glutathione depletion in epithelial lining fluid of lung allograft patients

The lower respiratory tract is protected against reactive oxygen species (ROS) by a complex antioxidant system. In the epithelial lining fluid (ELF), glutathione (L-alpha-glutamyl-L-cysteinylglycine, GSH) is essential for adequate protection of pneumocytes from potential toxicity mediated by extracellular hydrogen peroxide (H2O2). We assessed the concentration of total GSH in bronchoalveolar lavage fluid (BALF) in lung allograft patients in the absence and presence of acute rejection. Bronchoalveolar lavage (BAL) and biopsies were performed concurrently on 36 occasions in 17 patients who had undergone lung transplantation. BALF samples were divided into two groups on the basis of presence or absence of acute lung rejection on transbronchial biopsy. Seven BALF samples were obtained from control subjects for comparison. The BALF data demonstrated significantly lymphocyte recruitment and evidence of lung injury during acute rejection episodes. Transplant allografts without rejection showed significant depletion of total GSH in the ELF as compared with that of normal volunteers (94.0 +/- 9.7 microM versus 302.6 +/- 40.8 microM, p < 0.01). Transplant allografts with acute rejection had a slightly higher GSH concentration in their ELF (179.8 +/- 34.7), but this was still lower than control values. The deficiency of total GSH in the alveolar fluid may predispose lung allografts to extracellular H2O2-mediated toxicity.     

Histopathologic findings from 2-year protocol biopsies from a U.S. multicenter kidney transplant trial comparing tarolimus versus cyclosporine: a report of the FK506 Kidney Transplant Study Group

BACKGROUND: This paper reports the histopathologic results of 2-year protocol biopsies from patients who were enrolled in the U.S. FK506 kidney transplant study . METHODS: Recipients of cadaveric kidney transplants were randomized to tacrolimus or cyclosporine therapy. Patients active in the trial at 2 years after transplantation were approached for a protocol biopsy. Biopsies were scored by the Banff classification in a blinded fashion by one pathologist. RESULTS: A total of 144 patients (41.3% of those active at 2 years) had a 2-year protocol biopsy performed; 79 patients were treated with tacrolimus and 65 patients were treated with cyclosporine. Evidence of acute rejection was found in seven (8.9%) of the 2-year biopsies in tacrolimus-treated patients and six (9.2%) cyclosporine-treated patients. Chronic allograft nephropathy was found in 49 (62.0%) tacrolimus biopsies and 47 (72.3%) cyclosporine biopsies (P=0.155). There were no apparent histopathologic differences between the tacrolimus and cyclosporine biopsies. The occurrence of chronic allograft nephropathy was significantly higher in patients who received a graft from an older donor (P<0.01), who experienced presumed cyclosporine or tacrolimus nephrotoxicity (P<0.001), who developed a cytomegalovirus infection (P=0.038), or who experienced acute rejection in the first year after transplantation (P=0.045). A multivariate analysis showed that nephrotoxicity and acute rejection were the most significant predictors for chronic allograft nephropathy. CONCLUSIONS: The occurrence of histologic acute rejection was rare at 2 years, confirming the absence of subclinical acute rejection in these late biopsies. A majority of the biopsies showed features consistent with chronic allograft nephropathy that was associated with acute rejection (particularly in cyclosporine-treated patients), nephrotoxicity, and cytomegalovirus infection in the first year. This suggests that nonimmunologic factors, such as drug-induced toxicity, may play an important role in chronic allograft nephropathy.     

The diagnosis of ventilator-associated pneumonia: a comparison of histologic, microbiologic, and clinical criteria

STUDY OBJECTIVE: To evaluate histologic, microbiological, and clinical criteria in the recognition of ventilator-associated pneumonia (VAP) in patients who died while mechanically ventilated. METHODS: The study group consisted of 39 patients who died after a mean of 14 days of mechanical ventilation. Postmortem fiberoptic bronchoscopy (FOB) and open lung biopsy were performed with collection of specimens initiated <1 h after death. The microbiological specimens included suction catheter aspirate of tracheal secretions, FOB-guided protected specimen brush (PSB) of tracheal secretions, blindly placed PSB in a distal airway, FOB-guided PSB in a distal airway, and FOB-guided BAL fluid (BALF) in a distal airway. Qualitative bacteriologic study was performed on all specimens, and quantitative bacteriologic study was performed on all but the suction catheter aspirate of the trachea. A biopsy specimen of peripheral lung parenchyma from the same region sampled by FOB was sent for quantitative culture and histologic analysis. The BALF was analyzed for cell population and percent of neutrophils containing intracellular organisms. The clinical criteria selected for comparison with histologic and microbiological results included a temperature > or =38.5 degrees C during the 48 h prior to death, a WBC count > or =15,000/mm3 in the 48 h prior to death, presence of a bacterial or fungal pathogen on the last sputum culture, radiographic worsening in the week prior to death, and worsening gas exchange defined as a 15% decrease in the PaO2/fraction of inspired oxygen ratio in the 72 h prior to death. RESULTS: None of the quantitative cultures had a reliable positive predictive value for histologic pneumonia. None of the five clinical criteria tested showed agreement with the presence or absence of histologic pneumonia. There was a significant correlation between qualitative and quantitative microbiological results from the distal airway/FOB-guided PSB, distal airway/BALF, and quantitative culture of the lung parenchyma. Also, suction catheter aspirate of the trachea had a sensitivity of 87% in recognizing the bacterial species simultaneously present in lung parenchyma. None of the patients with histologic pneumonia had <50% neutrophils in the BALF. CONCLUSIONS: Neither the bacterial, density from the four airway quantitative cultures, nor the bacterial density from quantitative culture of lung parenchyma accurately separated the histologic pneumonia and nonpneumonia groups. No clinical criteria or combination of clinical criteria correlated with the presence or absence of histologic pneumonia. A BALF with <50% neutrophils had a 100% negative predictive value for histologic pneumonia. A BALF quantitative culture had a sensitivity of 63%, specificity of 96%, and positive predictive value of 91% in recognizing sterile lung parenchyma. Thus, BALF may have a role in excluding pneumonia/infection in the ventilated patient. Antibiotic choice for the empiric therapy of VAP can be accurately guided by the microbial population recognized through culture of a tracheal suction catheter aspirate.     

Suramin inhibits glucose-induced Ca2+ response in single rat pancreatic beta cells

To perform a retrospective pilot study of the potential role of mast cells in acute and chronic rejection of the lung allograft, transbronchial biopsies of 29 patients with acute rejection and six patients with bronchiolitis obliterans were stained with antibodies to mast cell tryptase. The number of mast cells per unit area were counted, and compared with a control group of normal lung biopsies stained in a similar fashion. Increasing grades of acute rejection were associated with progressively more mast cells per high-power microscopic field. The presence of bronchiolitis obliterans was accompanied by the greatest numbers of mast cells. Mast cells may play a role in the acute rejection response to the lung allograft and in the development of bronchiolitis obliterans.     

Value of CT angiography for postoperative assessment of patients with iliac artery aneurysms who have received endovascular grafts

OBJECTIVE: To determine the pathologic outcome in human immunodeficiency virus (HIV)-seropositive individuals with nonspecific bronchoalveolar lavage (BAL) cytology. STUDY DESIGN: The study group consisted of 126 cytologically negative or nonspecific BAL specimens from HIV-seropositive adults. Concurrent microbial cultures and transbronchial biopsies, as well as subsequent pulmonary cytology, lung biopsy or autopsy results were reviewed. Additionally, the cytologic morphology of specimens from patients found to have a potential bacterial pathogen was reviewed. RESULTS: In the 126 cases with nonspecific BAL cytology, a potential pulmonary pathogen was identified from a concurrent or subsequent pathologic specimen in 27% of cases, while no pathogen was identified in 73% of cases. Bacteria and fungi were the most common pathogens identified. Microbial cultures alone identified the pathogen in 59% of cases, while transbronchial biopsy added information in only 9%. Specimens with marked acute inflammation often yielded bacterial pathogens on microbial culture. CONCLUSION: A potential pulmonary pathogen can be identified in 27% of HIV-seropositive individuals with negative BAL cytology using other diagnostic modalities. Bacterial pathogens are most common and are usually identified by microbial culture. Marked acute inflammation in a BAL specimen is often associated with bacterial pneumonia.     

Evaluation of biopsy classification for rejection: relation to detection of myocardial damage by monoclonal antimyosin antibody imaging

OBJECTIVES: This study sought to compare the histologic grades of rejection in endomyocardial biopsy specimens with the global estimate of myocardial transplant-related cardiac damage detected by myocardial uptake of monoclonal antimyosin antibodies. BACKGROUND: The diagnosis and treatment of acute cardiac allograft rejection is based on the interpretation of endomyocardial biopsies. Because allograft rejection is a multifocal process and biopsy is obtained from a small area of the right ventricle, sampling error may occur. Global assessment of myocardial damage associated with graft rejection is now possible with the use of antimyosin scintigraphy. The present study was undertaken to compare the histologic grades of rejection in endomyocardial biopsy specimens with the global assessment of transplant-related myocardial damage detected by antimyosin scintigraphy. METHODS: Biopsies (n=395) from 112 patients were independently interpreted by three pathologists in a blinded manner according to the original Stanford four-grade (normal, mild, moderate and severe) and the current International Society of Heart and Lung Transplantation (ISHLT) seven-grade (0, 1A, 1B, 2, 3A, 3B and 4) classifications. The results were correlated with 395 antimyosin studies performed at the time of the biopsies. The heart/lung ratio of antimyosin antibody uptake was used to assess the severity of myocardial damage. RESULTS: In the Stanford biopsy grade classification, significantly higher antimyosin uptake, indicating increasing degrees of myocardial damage, were associated with normal (1.78+/-0.26), mild (1.88+/-0.31) and moderate (1.95+/-0.38) biopsy classifications for rejection (p < 0.01). In the ISHLT classification, significant differences were detected only for antimyosin uptake associated with grades 0 (1.77+/-0.26) and 3A (1.98+/-0.39) but not for intermediate scores (1A, 1B and 2). In view of the similar intensity of antibody uptake among the various grades, ISHLT biopsy scores were regrouped: normal biopsies in grade A; 1A and 1B as grade B; and 2 and 3A as grade C. Antimyosin uptake in grades A, B and C was 1.78+/-0.26, 1.88+/-0.31, 1.95+/-0.38, respectively (p < 0.01). CONCLUSIONS: The current ISHLT seven-grade scoring system does not reflect the progressive severity of myocardial damage associated with heart transplant rejection. Because myocardial damage constitutes the basis of treatment for allograft rejection, there is a need to reevaluate the ISHLT grading system, given its importance for multicenter trials.     

Airway versus transbronchial biopsy and BAL in lung transplant recipients: different but complementary

Lung transplantation is now an established therapeutic intervention for end-stage cardiopulmonary disease in humans. Chronic rejection, in the form of bronchiolitis obliterans syndrome (BOS), remains the commonest cause of morbidity and mortality in those surviving more than 3 months. The pathology of BOS involves airway changes. We have evaluated the potential for endobronchial biopsies (EBB) to complement existing sampling methods used in allograft monitoring and have compared the results of EBB findings with those of bronchoalveolar lavage (BAL) and transbronchial biopsy (TBB) in 18 clinically stable patients. We found that all the EBB had inflammatory cells present but that only five TBB specimens had evidence of inflammation, with airway material being present in 78% of the TBB. Paired BAL and EBB yielded different results, with no correlations between total macrophages, lymphocytes, CD4+ cells or CD8+ cells. We conclude that endobronchial biopsies are potentially useful as an additional sample for the monitoring of inflammation in lung allografts, since they yield different, and potentially complimentary, information to bronchoalveolar lavage and transbronchial biopsy.     

Assessment of complications in patients with lung transplantation with high resolution computerized tomography

INTRODUCTION: High Resolution Computed Tomography (HRCT) has been used by many authors to study the early complications of lung transplantation. Bronchoscopy, transbronchial biopsy and the clinical parameters are the tools of choice to diagnose such complications; HRCT showed excellent sensitivity (100%) and good specificity (93%) especially in detecting bronchial stenoses. We report the preliminary results of HRCT in detecting early/late complications in lung transplant recipients. MATERIAL AND METHODS: Sixteen lung transplant recipients (5 single and 11 double transplants) were examined with HRCT at the Servizio Speciale Diagnostica V of "La Sapienza" University (Rome, Italy). The CT findings were compared with the results of bronchoscopy and respiratory function tests. The patients (8 men and 8 women; age range: 18-57 years, mean: 37.5) had cystic fibrosis (9), emphysema (3), alpha-1-antitrypsin deficiency (1), idiopathic pulmonary fibrosis (2), and bronchiectasis (1). RESULTS AND DISCUSSION: During the follow-up, one patient died of pulmonary edema. CT findings were normal in 3 patients and mild pleural effusion was seen in 2. The other HRCT findings were: bronchial stenosis in 5 cases (which was bilateral in 1) and bronchial dehiscence in 1 patient; four cases of infection (1 CMV, 1 aspecific bacterial pneumonia, 1 Chlamydia psittacea and 1 Aspergillosis) and one of brochiolitis obliterans. A patient was treated for acute and one for chronic rejection. A CMV infection involved only the native lung in a patient. CT is easy to perform and a repeatable and well-tolerated tool with high sensitivity (100%) and good specificity (93%) in the early diagnosis of complications, particularly bronchial stenoses, which complications are often missed at bronchoscopy or clinically silent. CT should be always performed before bronchoscopy because it can provide valuable information for bronchoscopy targeting. CONCLUSIONS: In agreement with other authors we consider HRCT a very useful tool in the early diagnosis of the complications following lung transplantation.     

Mononuclear phagocyte populations in the transplanted human lung

BACKGROUND: Dendritic cells (DC) are essential for the development of alloreactivity, however, little has been published regarding the distribution and phenotype of these and related mononuclear cells in human lung transplantation. METHODS: Lung frozen sections were examined for the presence of CD1a+ DC and for mononuclear cells and alveolar macrophages expressing CD11b and CD68. The effects of transplantation and immunosuppression were assessed by comparison of normal transplant transbronchial biopsy specimens to specimens from unused donor lungs; the normal transbronchial biopsy specimens also were compared with those showing rejection or obliterative bronchiolitis. RESULTS: All biopsy specimens, including those with obliterative bronchiolitis, showed a marked depletion of CD1a+ DC in lung allografts. This has not been described previously. In addition, transplantation and immunosuppression reduced alveolar macrophage coexpression of CD68 and CD11b, and this was reversed in acute rejection. CONCLUSION: The roles of pulmonary DC and other mononuclear phagocyte subpopulations need to be further defined, and data from animal models of lung transplantation should be interpreted with caution.     

Surgical treatment of posterior fossa tumors in infancy and childhood: techniques and results

Fetal/neonate kidneys obtained at the time of autopsy were utilized to determine a suitable needle biopsy gauge to obtain renal parenchyma for histologic evaluation. Twenty-one fresh kidney specimens from 11 fetuses/neonates between 16-40 weeks gestation were used to obtain needle biopsies using 20-, 18-, 16-, and 14-gauge biopsy catheters. The specimens were graded according to the presence of normal histologic features of renal parenchyma. Seventy-five renal biopsies were obtained. The biopsy histology was interpreted using a grading system based on the presence of normal features of the renal parenchyma. Sixty-three (84%) of the samples were graded histologically as adequate (cortex or medulla present). Samples with both cortex and medullary structures present (completely adequate) were obtained in 39/63 (62%) of these adequate biopsies. The 14- and 16-gauge biopsy catheters gave the best results, respectively yielding 79 and 69% completely adequate biopsies. This is in contrast to the 20- and 18-gauge catheters that respectively yielded 35 and 25% completely adequate biopsies. Our initial results indicate that adequate kidney biopsies can be obtained. However, the current technique is associated with core sample disruption when the smaller gauge catheters are used. This could account for the low rate of completely adequate samples with the smaller gauge catheters. A different sampling technique is needed to overcome sample disruption, to determine the smallest catheter gauge that will yield a suitable tissue sample for histologic evaluation.     

Immunologic monitoring in lung allograft recipients

To identify patients with increased risk of chronic lung allograft rejection, we assessed the utility of an in vitro biopsy-derived lymphocyte growth assay and serum anti-HLA antibody screening as a complement to currently available methods of monitoring lung allograft recipients. Lymphocyte growth assay was performed on bronchoscopic fragments of tissue cultured in medium with rIL-2. Seventy-nine biopsies from 31 lung transplant recipients were tested by lymphocyte growth assay, and results were correlated with histopathology findings. Positive lymphocyte growth was found in 12/26 (46%) episodes of acute rejection, 5/44 biopsies without rejection (11%), and 0/9 episodes of bronchitis. Positive lymphocyte growth was seen in 7/16 (44%) grade A1 rejections and in 5/10 (50%) grade A2 rejections, as opposed to only 5/44 (11%) grade A0 (no rejection) biopsies (P < 0.01 for both A1 and A2 with respect to A0). Actuarial probability of remaining free from obliterative bronchiolitis (OB)* tended to be higher in patients who did not exhibit lymphocyte growth in biopsies. Sequential samples of sera obtained at the time of the biopsy were screened for lymphocytotoxic anti-HLA antibodies. Twenty-two of 44 recipients (50%) developed anti-HLA antibodies during the first postoperative year, exhibiting greater than 10% reactivity to an HLA reference panel of lymphocytes in four or more consecutive serum samples. Actuarial survival of lung allograft recipients with anti-HLA antibodies (n = 22) was lower than in those without anti-HLA antibodies (n = 22; P = 0.03). Of the 22 antibody producers, 7/12 died as a consequence of OB. Of the 22 non-antibody-producers, 1/2 deaths occurred as a consequence of OB. Anti-HLA antibodies were present in 9/11 instances of OB (82% sensitivity) and in 13/33 patients without OB (61% specificity; P = 0.03). These data indicate that lung transplant recipients with positive lymphocyte growth and anti-HLA antibodies are at an increased risk of chronic allograft rejection.     

Histologic specimen collection in pulmonary hypertension using percutaneous, transvascular biopsy--animal experiment and initial clinical data]

Pulmonary hypertension is a severe multietiological disease largely resistant to treatment. Biopsy is often necessary to establish differential diagnosis. In pulmonary hypertension transbronchial pulmonary biopsy is contraindicated and open lung biopsy is the method of choice. In our paper we report about experimental results in animals and first clinical data on a new biopsy technique (percutaneous transluminal biopsy, PTB) providing access to histology in pulmonary hypertension without the need of surgery. In a subset of animals pulmonary hypertension was produced experimentally. In addition, we carried out the PTB in patients with bronchial carcinoma. Our preliminary results demonstrate that sufficient material could be gained for the histologic evaluation of pulmonary parenchyma and in pulmonary vessels. No complications have been noted so far.     

Lipoid pneumonia in lung cancer: radiographic and pathological features

BACKGROUND: Obstructive pneumonia, a synonym for endogenous lipoid pneumonia, is often seen in patients with lung cancer, but details of this condition are still uncertain. METHODS: To elucidate the features of obstructive pneumonia, we radiopathologically studied 147 patients with lung cancer that had been resected. RESULTS: Gross inspection of the resected materials revealed evidence of endogenous lipoid pneumonia in 33 of the 147 patients with radiography that corresponded to obstructive pneumonia. We classified the 33 cases into three types as follows: (1) type I lipoid pneumonia, localized to the lung parenchyma distal to an airway obstructed by a tumor (23 cases); (2) type II lipoid pneumonia, features of type I lipoid pneumonia and consecutively spreading to the adjacent segment whose airway was not affected (five cases); (3) type III lipoid pneumonia, features of type II lipoid pneumonia and spreading to the isolated segments (five cases). Lipoid pneumonia was found in 16 of 89 (18%) adenocarcinoma cases and in 17 of 55 (31%) squamous cell carcinoma cases. In type I lipoid pneumonia, squamous cell carcinoma cases were predominant over adenocarcinoma cases (14 vs nine cases), but in type III lipoid pneumonia, adenocarcinoma cases predominated (four vs one case). Further, in cases of type III lipoid pneumonia, radiographs frequently revealed that lung cancers were cavitated. CONCLUSION: Lipoid pneumonia in lung cancer may be associated with factors that play a larger role than the cancer alone. It can be speculated that transbronchial dissemination of breakdown products of adenocarcinoma cells, including mucin, may contribute to the spread of the non-obstructive component of lipoid pneumonia, because the local physical effect of obstructed bronchus does not affect the non-obstructive component.     

Follicular fluid immunoreactive-inhibin concentrations in relation to follicular diameter and estradiol-17 beta, progesterone and testosterone concentrations in individual ovarian follicles in buffalo, Bubalus bubalis

BACKGROUND: Mycophenolate mofetil reduces episodes of biopsy-proven acute cellular rejection or treatment failure in the first year after kidney transplantation; however, limited data exist regarding the efficacy after lung transplantation. METHODS: In a 2-center, nonrandomized concurrent cohort study (level III evidence), we analyzed the incidence of biopsy-proven acute cellular rejection (International Society for Heart and Lung Transplantation grade > or=A2) and decrement in pulmonary function during the first 12 months after successful lung transplantation. All patients received induction immunosuppression with antithymocyte globulin (< or=5 days' duration), cyclosporine and prednisone, in addition to either mycophenolate mofetil (2.0 g/d) [n=11] or azathioprine (1 to 2 mg/kg per day) [n=11]. RESULTS: During the first 12 months after lung transplantation, the mycophenolate mofetil group experienced significantly fewer episodes of acute cellular rejection than the azathioprine group (0.26+/-0.34 vs 0.72+/-0.43 episodes/100 patient-days [mean+/-SD], p < 0.01; 95% CI for the difference=0.126 to 0.813). The change in forced expiratory volume -1 second [deltaFEV1] (liters) between the 3rd and 12th months after lung transplantation was analyzed for the two treatment groups. For this interval, deltaFEV1 for the mycophenolate mofetil group was +0.158+/-0.497 L vs -0.281+/-0.406 L for the azathioprine group (p < 0.05; 95% CI for difference=+0.0356 to 0.843). During the first year, there was 1 death in each group attributed to bronchiolitis obliterans syndrome with concurrent pneumonia. There were no differences in incidence of cytomegalovirus or bacterial infections between the treatment groups; however, a higher prevalence of aspergillus sp airway colonization in bronchoalveolar lavage fluid was observed for the mycophenolate mofetil group (p < .05). The prevalence of bronchiolitis obliterans syndrome at 12 months was 36% for the azathioprine group vs 18% for the mycophenolate mofetil group (p=NS). CONCLUSIONS: Our preliminary experience with mycophenolate mofetil after lung transplantation suggests a decreased incidence of biopsy-proven acute cellular rejection. Furthermore, less decline in FEV1 after 12 months may suggest a reduced incidence or delayed onset for development of bronchiolitis obliterans syndrome. Prospective randomized trials with low beta error (level I evidence) should be performed to assess the efficacy of mycophenolate mofetil vis-à-vis acute allograft rejection and bronchiolitis obliterans syndrome.     

The effect of flumazenil on subclinical psychometric or neurophysiological alterations in cirrhotic patients: a double-blind placebo-controlled study

Posttransplant lymphoproliferative disorder (PTLD) is associated with Epstein-Barr virus (EBV), and may clinically resemble acute allograft rejection. Three methods to show EBV in tissue were evaluated in 15 liver allograft biopsies from 12 patients including four with PTLD: (1) semiquantitative polymerase chain reaction (PCR) for EBV DNA; (2) in situ hybridization for EBV RNA (EBER); and (3) immunoperoxidase for EBV latent membrane protein (LMP). Index cases had a PCR dot blot result of "positive" or "weak positive." Findings were correlated with histology, clinical data, therapy, and outcome. All four PTLD patients had a clinical diagnosis of acute rejection. All four showed EBV: PCR 4, EBER 4, LMP 3, Liver function tests were elevated in three, but EBV viral capsid antigen (VCA) IgM was not increased in three, but EBV viral capsid antigen (VCA) IgM was not increased in three. Immunosuppression was withdrawn and all four patients underwent a second transplantation. One died 4 days posttransplant with disseminated PTLD, two died of sepsis at 1.5 and 14 months, and one is well at 3 years without PTLD. Eleven biopsies without PTLD showed: acute rejection 7, acute rejection and hepatitis 1, hepatitis B 1, and non-inflammatory changes 2. In this group, EBV results included: PCR weak positive in 10 and 1+ in one, EBER negative in ten and rare positive cells in one, LMP negative in 11. Liver function tests were elevated in 10, whereas VCA IgM was not increased in three and increased in one. Patients with acute rejection were treated with increased immunosuppression: none developed PTLD, with follow-up of at least 6 months in nine cases. Two patients died within 4 months of biopsy. One patient with PTLD in tonsils had a liver biopsy showing both acute rejection and EBV (PCR 1+, rare EBER + small cells). Histological studies combined with special EBV detection methods, can be useful to evaluate atypical lymphoid infiltrates in liver allograft biopsies and confirmation of a diagnosis of PTLD. All three methods are useful; EBER and PCR are the most sensitive. EBER and LMP can use paraffin sections.     

A semiquantitative approach to the evaluation of acute cardiac allograft rejection at endomyocardial biopsy

BACKGROUND: Histopathologic criteria for grading of acute cardiac allograft rejection are focused on the most severe lesion that is recognized among the myocardial fragments provided by each endomyocardial biopsy specimen. Considering the distribution of rejection lesions among all the fragments improved the accuracy in characterizing the severity of rejection in pathologic studies. This study was undertaken to verify the usefulness of a semiquantitative evaluation of endomyocardial biopsy specimens, consisting of the calculation of the proportion of fragments showing rejection in the clinical setting. METHODS: Of the 2386 biopsy specimens obtained during the first posttransplantation year in 168 consecutive cardiac allograft recipients, 290 biopsy specimens constituted by > or = 3 adequate fragments and showing rejection not followed by treatment (n = 159) or being the first biopsy specimen prompting treatment with augmented immunosuppression for that rejection episode (n = 131) were selected. These biopsy specimens (index biopsy specimens) were grouped according to whether rejection was present in < or = 33%, > 33% to < or = 67%, and > 67% of the fragments. The rejection grade (according to the standardized grading system) and the proportion of fragments positive for rejection were correlated with the occurrence of clinical symptoms and signs of rejection at index biopsy and with the results of the next biopsy. RESULTS: Rejections graded > or = 3A were more frequently symptomatic (36% vs 9% for those graded < 3, p < 0.0001), as were those involving increasing proportions of fragments (< or = 33%: 5 of 124, 4%; > 33 to < or = 67%: 13 of 99, 13%; > 67%: 19 of 67, 28% [p < 0.0001]). Spontaneous resolution after untreated biopsies was more frequent in focal (grade 1A and 2) than in diffuse mild (1B) rejections (68% vs 38% [p < 0.04]), whereas progression to grade 3A or greater was less frequent (4% vs 27% [p < 0.01]). Increasing proportions of positive fragments were associated with lower frequencies of spontaneous resolution (p < 0.05) and higher frequencies of worsening (9%, 22%, 43% [p < 0.009]) or progression to grade 3A or greater (2%, 6%, 28% [p < 0.005]). Complete resolution after treatment was less frequent for increasing proportions of positive fragments at index biopsy (80%, 66%, 49% [p < 0.05]). CONCLUSIONS: Diffuse versus focal rejection pattern and the proportion of positive fragments seem to be clinically relevant in terms of occurrence of symptoms, spontaneous evolution, and response to treatment.     

Serial changes during acute cardiac allograft rejection: quantitative ultrasound tissue analysis versus myocardial histologic findings

OBJECTIVES: The aim of this study was to assess 1) whether quantitative ultrasound tissue analysis by serial measurements of myocardial echo amplitudes can detect and monitor the onset and degree of acute cardiac rejection, as well as its resolution of acute rejection during treatment, and 2) whether changes in myocardial echo amplitudes are modified by repeat additional rejection episodes. BACKGROUND: Previous experimental studies, all involving heterotopic heart transplantation, have consistently shown reproducible alterations in myocardial echo amplitude during acute rejection episodes untreated by immunosuppressive agents. METHODS: Two-dimensional echocardiographic long-axis views were obtained daily under strict standardization in 12 dogs after heterotopic cervical heart transplantation (mean survival time 16.1 days) and digitized into a 256 x 256 x 8 matrix. Myocardial echo amplitudes were analyzed by gray level histogram statistics in regions of interest (45 x 12 pixels) within the proximal septum and posterior wall and correlated with the results of daily transmural myocardial biopsies. Maintenance immunosuppressive therapy consisted of cyclosporine, azathioprine and steroids. Additive steroids were given during acute cardiac rejection. RESULTS: All dogs experienced at least one moderate or severe episode of acute cardiac rejection. Successful resolution and repeat acute rejection were observed in three dogs. On 65 days, the left ventricular biopsy specimens showed no evidence of acute rejection. Mild acute rejection was present on 36, moderate on 29 and severe rejection on 40 days. End-diastolic mean (+/- SD) gray level increased progressively from 100.7 +/- 20.4 for no acute cardiac rejection to 113.8 +/- 23.1 for mild rejection (p = NS vs. no rejection) to 126.0 +/- 16.1 for moderate rejection (p < 0.01) and to 136.3 +/- 12.6 for severe rejection (p < 0.01). In each individual dog, a correlation between daily measurements of mean gray levels and histologic cardiac rejection grades was found (rmean = 0.80 +/- 0.14 [range 0.57 to 0.97], n = 12). In three dogs with transient complete histologic resolution of acute cardiac rejection, mean gray level did not return to values before rejection (108.0 +/- 15.4 vs. 87.2 +/- 8.4). The subsequent second episode of rejection was characterized by higher gray level values than those associated with the first rejection episode (141.3 +/- 14.4 vs. 124.3 +/- 20.9). CONCLUSIONS: Acute cardiac rejection is associated with a progressive increase in mean gray level. Changes in myocardial echo amplitudes in individuals may thus prove a useful tool for the noninvasive detection and monitoring of acute rejection. Increased mean gray level values after resolution of rejection may indicate persistent structural tissue abnormalities after rejection and demonstrate the need to define new baseline values after histologic resolution of an acute rejection episode.