Lymphangioleiomyomatosis: what do we know and what are we looking for?

Lymphangioleiomyomatosis (LAM) is a rare disease characterised by proliferation of abnormal smooth muscle-like cells (LAM cells) leading to progressive cystic destruction of the lung, lymphatic abnormalities and abdominal tumours. It affects predominantly females and can occur sporadically or in patients with tuberous sclerosis complex. This review describes the recent progress in our understanding of the molecular pathogenesis of the disease and LAM cell biology. It also summarises current therapeutic approaches and the most promising areas of research for future therapeutic strategies.

Smoking-related interstitial lung diseases

In pulmonary pathology, a wide spectrum of morphological changes is related to the consequences of smoking, and recognizing them on surgical specimens and on small transbronchial biopsies represents a challenge for the pathologist. Respiratory bronchiolitis, also referred to as smoker's bronchiolitis, is a common histologic feature found in the lung tissue of cigarette smokers. When identified as the sole histopathologic finding in the clinical setting of symptomatic interstitial lung disease, a diagnosis of respiratory bronchiolitis-interstitial lung disease is made. Since smoking is recognized to cause a variety of histologic patterns encompassing respiratory bronchiolitis, respiratory bronchiolitis-interstitial lung disease, desquamative interstitial pneumonia and pulmonary Langerhans cell hystiocytosis, smoking-related interstitial lung disease may be a useful concept to keep in mind for the pathologists. The relationship of smoking with each of these entities has been largely established on the basis of epidemiologic evidence. Although they have been retained as distinct and separate conditions in various classifications of interstitial lung diseases, these entities share a number of clinical, radiologic, and pathologic features suggesting that they represent a spectrum of patterns of interstitial lung disease occurring in predisposed individuals who smoke. Evaluation of histologic features, particularly in surgical lung biopsy samples, is important in making the distinction between these disorders. However, even after tissue biopsy, it may sometimes be difficult to clearly separate these entities. Recently, respiratory bronchiolitis-interstitial lung disease with fibrosis has been described and postulated that this is a smoking-related condition distinct from fibrotic non-specific interstitial pneumonia.

IPF: new insight on pathogenesis and treatment

Recent years have seen a robust influx of exciting new observations regarding the mechanisms that regulate the initiation and progression of pulmonary fibrosis but the pathogenesis remains poorly understood. The search for an alternative hypothesis to unremitting, chronic inflammation as the primary explanation for the pathophysiology of idiopathic pulmonary fibrosis (IPF) derives, in part, from the lack of therapeutic efficacy of high-dose immunosuppressive therapy in patients with IPF. The inflammatory hypothesis of IPF has since been challenged by the epithelial injury hypothesis, in which fibrosis is believed to result from epithelial injury, activation, and/or apoptosis with abnormal wound healing. This hypothesis suggests that recurrent unknown injury to distal pulmonary parenchyma causes repeated epithelial injury and apoptosis. The resultant loss of alveolar epithelium exposes the underlying basement membrane to oxidative damage and degradation. Emerging concepts suggest that IPF is the result of epithelial-mesenchymal interaction. The initiation of this fibrotic response may depend upon genetic factors and environmental triggers; the role of Th1 or Th2 cell-derived cytokines may also be important. This process appears to be unique to usual interstitial pneumonia/IPF. It is clear that IPF is a heterogeneous disease with variations in pathology, high-resolution computed tomography findings, and patterns of progression. Idiopathic pulmonary fibrosis is a complex disorder, and no unifying hypothesis has been identified at present that explains all the abnormalities.

Lung function predicts lung cancer risk in smokers: a tool for targeting screening programmes

The relationship between smoking, lung cancer and airflow obstruction is recognised but it is unclear whether the presence of minimal lung function damage constitutes an independent risk factor for the development of lung cancer. In order to identify those individuals at higher risk of lung cancer on the basis of functional impairment, we evaluated baseline pulmonary function tests of 3,806 heavy smokers undergoing annual chest computed tomography screening, and compared the forced expiratory volume in 1 s (FEV(1)) % predicted of 57 lung cancer cases and that of 3,749 subjects without cancer. We obtained odds ratios (ORs) of lung cancer and the corresponding 95% confidence intervals (CIs) using unconditional logistic regression, adjusting for age, sex, study and smoking variables. Compared with subjects with FEV(1) >or=90% pred, the OR of lung cancer was 2.45 (95% CI 1.39-4.33) for subjects with FEV(1) <90% pred and 2.90 (95% CI 1.34-6.27) for subjects with FEV(1) <70% pred. These data show that even a relatively small reduction in FEV(1) % pred is a significant predictor of increased lung cancer risk. Test screening for lung cancer using airflow obstruction with FEV(1) <90% is a strategy worth future consideration.

Role of CMV pneumonia in the development of obliterative bronchiolitis in heart-lung and double-lung transplant recipients

Obliterative bronchiolitis (OB) is the main cause of late mortality after lung transplantation. Cytomegalovirus infection has been associated with late graft failure. The aim of this study was to determine whether the development of OB was related to CMV pretransplant serological status and to CMV infections. The study group comprised 36 lung transplant recipients (27 HLT and 9 DLT) who survived more than 4 months, of whom 47% developed OB (defined by the persistence of an unexplained obstructive disease: FEV1/VC < 0.7). OB occurred more frequently: (1) in seronegative recipients with seropositive donors (8/9) than in seropositive recipients (7/19) or seronegative well-matched recipients (2/8); and (2) in patients who experienced CMV pneumonia (11/16) and CMV recurrence (11/16). Since matching seronegative recipients is the best way to prevent CMV infection, we believe that seronegative grafts must be reserved for seronegative recipients.

Salivary Streptococcus mutans and Lactobacillus sp levels in cardiac children

This study assesses salivary conditions of 20 children with cardiac disease comparing with a control group of 15 healthy children. The results showed that there was no difference between the groups on salivary flow, buffer capacity and the level of Streptococcus mutans (Sm). The test group i.e., children with cardiac disease, showed a lower level of Lactobacillus sp. The association between the usage of antibiotics and the risk of developing caries, measuring the level of Streptococcus mutans and Lactobacillus sp., showed that children taking antibiotics frequently had a significant lower level of Lactobacillus sp (p<0.05) than healthy children. This association was not found on relation to the levels of Streptococcus mutans.

Pulmonary Langerhans cell Histiocytosis

Pulmonary Langerhans cell Histiocytosis is a rare granulomatous disease affecting both sexes, with greater incidence in the second and third decades of life; smoking appears to be the most important risk factor. Its etiology is unknown, although there are data indicating an uncontrolled immune response as possible cause, sustained by the Langerhans cells, antigen presenting cells for T lymphocytes, and their accumulation in the distal bronchioles; these cells express on their surface the CD1a and CD1c antigens, and the B7 molecule, essential for activating quiescent T lymphocytes. In its evolution the granuloma is characterized by the progressive reduction in the LC number, with the increase of fibrosis, surrounding and destroying the bronchiolar lumen; the remaining of the lumen, or the traction exerted by fibrous tissue on the adjacent alveolar spaces leads to the cyst development. Vascular involvement occurs frequently, and may explain the onset of pulmonary hypertension in advanced cases of the disease. The disease may be asymptomatic, or it may present with aspecific respiratory signs and symptoms, and has characteristic radiological findings, being included in the group of cysticaerial parenchymal alterations. The diagnosis could be suggested by the finding of a number of LC in BAL greater than 5%. Different therapies have been proposed, but it seems that the most important measure is smoking cessation.

First report of the Italian register for diffuse infiltrative lung disorders (RIPID)

RIPID was established in 1998 as a joint project of the major Italian scientific societies for Respiratory Medicine, with the aim to create an Italian Register on diffuse infiltrative lung disorders that can provide the basis for epidemiological and clinical studies of adequate sample size. In the period from May 1998 to December 2000, 1,382 cases were submitted from 54 Centers in 15 regions of Italy, 54.2% males (mean age +/- SD 50.5 +/- 16.8 years) and 45.8% females (50.2 +/- 15.3 years). A current smoking habit emerges in 18% of subjects; former smokers and never-smokers represent 26% and 56% of the total case series, respectively. The most frequent disease registered is idiopathic pulmonary fibrosis (37.6%), followed in decreasing order by sarcoidosis (29.2%), and Langherans' cell hystiocytosis (6.6%). High resolution computed tomography (HRCT) was considered as the most important tool for final diagnosis in the majority of cases (74.4%); 39.4% of patients underwent transbronchial biopsies, 39.2% bronchoalveolar lavage (BAL). A surgical biopsy was performed in 20.5% of patients. A web site has been activated from December 2000 (www.pneumonet.it/ripid), allowing prompt access to all information and scientific material concerning the project and to an electronic form for data collection that can be completed on-line.

Ear and nose involvement in systemic diseases

A whole range of otolaryngeal manifestations may occur as complications or represent the first symptom and sign of a variety of systemic diseases. Otolaryngologists are often the first physicians to recognize that otolaryngeal abnormalities are symptomatic of a broader disease and mandate a systemic approach to the problem. In the present study, the authors focus primarily on ear, nose and throat manifestations that may occur in the context of systemic diseases, discussing clinical manifestations and reviewing the salient histologic, laboratory, and serologic features.

Current strategies in the treatment of invasive Aspergillus infections in immunocompromised patients

Aspergillus infections have a very high mortality rate. Their incidence is growing because of the increasing number of immunocompromised patients. Treatment of Aspergillus infection is difficult, and the agents used have numerous adverse effects and toxicities. Recently, new and less nephrotoxic formulations of amphotericin B have come onto the market and other new drugs, such as voriconazole and terbinafine, are under evaluation for this infection. Restoration of host immune defences by tapering of immunosuppressive therapy in transplant patients or correction of granulocytopenia in haematological disease is the cornerstone of modern treatment of aspergillosis in immunocompromised patients. In patients with invasive aspergillosis it is very important to achieve therapeutic concentrations of antimycotic drugs as quickly as possible. Patients at high risk of developing aspergillosis (e.g. those with granulocytopenia) should be treated on the basis of clinical or radiological criteria alone if microbiological or histological diagnosis would significantly delay treatment. Conventional amphotericin B is still the first-line treatment for patients with invasive aspergillosis. In transplant patients receiving other nephrotoxic drugs, particularly cyclosporin, first-line therapy with one of the new amphotericin B formulations should be considered. If the emergence of renal toxicity in any patient precludes aggressive treatment, the patient should be switched to one of the new formulations of amphotericin B. For patients cured with amphotericin B, secondary prophylaxis is needed at the end of the intravenous therapy. Amphotericin B by aerosol or itraconazole are possible solutions. In non-invasive forms of aspergillosis, such as suppurative bronchitis, patients could be treated either with amphotericin B or itraconazole as first-line therapy.

Prognostic value of pulmonary hypertension in patients with chronic interstitial lung disease referred for lung or heart-lung transplantation

BACKGROUND

The purpose of this study was to identify precise and reliable prognostic parameters in patients affected by serious chronic interstitial lung disease, who were undergoing screening for lung or heart-lung transplantation.

METHODS

Hemodynamic and respiratory function parameters of 67 patients (43 with idiopathic pulmonary fibrosis, 18 with histiocytosis X, and 6 with lymphangioleiomyomatosis) undergoing clinical screening for lung transplantation.

RESULTS

Statistical analysis showed that hemodynamic and respiratory function parameters in patients affected by histiocytosis X and idiopathic pulmonary fibrosis were not related to survival time. Moreover, the degree of pulmonary hypertension showed no correlation between respiratory function parameters in all the groups of diseases examined. Patients affected with histiocytosis X, even with higher degrees of pulmonary hypertension, had a better survival rate (p < 0.0005) compared with patients with idiopathic pulmonary fibrosis.

CONCLUSIONS

Hemodynamic and respiratory parameters obtained during the clinical screening for lung transplantation do not predict survival and cannot be used as prognostic indicators.

Terbinafine in the treatment of non-immunocompromised compassionate cases of bronchopulmonary aspergillosis

Conventional treatments of broncho-pulmonary aspergillosis are often ineffective and result in associated side-effects. Terbinafine (a new allylamine derivative), although as active against Aspergillus in vitro as amphotericin B and itraconazole, is less effective in rodent models because of a rapid hepatic first-pass effect. As terbinafine is metabolized differently in humans, the aim of this work was to evaluate this drug, for the first time, in the treatment of seven immunocompetent patients with lower respiratory tract mycotic infections unresponsive to the usual antimycotic drugs. Diagnosis was based on identification of fungal isolates, worsening of respiratory function tests, chest radiographs and computerized tomographic (CT) scan changes, positive skin test, aspergillin precipitins and clinical history. Terbinafine was administered at doses ranging from 5 to 15 mg kg-1 day-1 depending on the clinical severity of the disease, and was given for 90-270 days depending on clinical progress and compliance. In three patients A. fumigatus was suppressed with resolution of signs and symptoms; four patients showed transitory A. fumigatus suppression with marked clinical and radiological improvement. During relapses no resistance to terbinafine was observed. No significant side-effects were detected. Terbinafine appeared to be as effective as amphotericin B and itraconazole in the treatment of bronchopulmonary aspergillosis in nonimmunocompromised patients. These preliminary results suggest that controlled studies are warranted.

Immunocytochemical detection of progesterone receptors. A study in a patient with primary pulmonary hypertension

Primary pulmonary plexogenic arteriopathy (PPPA) is one of the principal conditions in which pulmonary hypertension may be clinically unexpected. It occurs in the lung vessels in the absence of any demonstrable cause. Its high incidence in women of childbearing age combined with reports of disease following delivery of a child or assumption of oral contraceptives suggest that hormonal factors may play a role in the pathogenesis of PPPA. The suspicion that the pulmonary vascular lesions occurring in PPPA could represent the effect of a hormonal mediated vascular hyperreactivity prompted the evaluation of the steroid hormone receptor status on lung tissue obtained from a women suffering from this disease who had a double-lung transplantation. By the immunocytochemical method performed on formalin fixed, paraffin-embedded lung tissue, we showed the presence of progesterone receptors (PR) in the nuclei of the myofibroblasts forming the arterial obstructive intimal proliferations and of the spindle cells present in the walls of the plexiform lesions. To enhance the staining and to facilitate the observation, we used a microwave-based antigen unmasking technique. The lack of estrogen receptors and the presence of PR could have increased, in the case, the sensitivity of the pulmonary muscular arteries to vasoconstrictory compounds. We hypothesize that on this substrate of a presumptive steroid-mediated vasoconstriction the sequence of the histologic lesions characteristic of pulmonary vascular hypertensive disease could have developed.

Selection and evaluation of recipients for heart-lung and lung transplantation: the Niguarda Hospital experience

Between January 1989 and February 1993, 52 patients were evaluated at Niguarda Hospital for lung or heart and lung transplantation. Of the 35 that entered the waiting list, a total of 19 were transplanted (14 at other institutes before our surgical programme became operative, and 5 at our hospital). Recipient selection and evaluation criteria, and timing of transplantation in the different diseases are discussed.