Thoracoscopy in pulmonary histiocytosis X

We report 4 cases of recurrent multiple pneumothorax in patients with diffuse interstitial lung disease diagnosed as histiocytosis X. These cases demonstrate the dual value of thoracoscopy in that disease: (1) it facilitates the diagnosis by showing the characteristic macroscopic aspect of the lung with multiple blebs and by enabling pulmonary biopsies to be performed; (2) it contributes to the treatment and prevention of pneumothorax by diffuse pleural poudrage. Immediate thoracoscopy should therefore be contemplated in special conditions, such as pulmonary interstitial lung disease with pneumothorax as first presentation.     

Severe pulmonary hypertension in histiocytosis X

Diminished exercise capacity in advanced pulmonary histiocytosis X does not appear to be related to ventilatory limitation but may be related to pulmonary vascular dysfunction. Pulmonary hemodynamics and respiratory function were studied in 21 consecutive patients with advanced pulmonary histiocytosis X, and compared with parameters of patients with other severe chronic lung diseases (29 patients with chronic obstructive pulmonary disease and 14 patients with idiopathic pulmonary fibrosis). All patients with pulmonary histiocytosis X displayed severe pulmonary hypertension: mean pulmonary arterial pressure, 59 +/- 4 mm Hg; cardiac index, 2.6 +/- 0.8 L/min/m(2); and total vascular pulmonary resistance, 25 +/- 3 IU/m(2) (p < 0.05, as compared with patients with other chronic lung diseases). Pa(O(2)) was similar in the three groups, whereas FEV(1) was lower in patients with other chronic lung diseases (p < 0.05). In contrast to other chronic lung diseases, the degree of pulmonary hypertension was not related to variables of pulmonary function in pulmonary histiocytosis X. Histopathology was available for 12 patients with pulmonary histiocytosis X and revealed proliferative vasculopathy involving muscular arteries and veins, with prominent venular involvement. Two consecutive lung samples (taken before and after the occurrence of pulmonary hypertension) were available for six patients with pulmonary histiocytosis X, and showed that pulmonary vasculopathy worsened, whereas parenchymal and bronchiolar lesions remained relatively unchanged. These results indicate that pulmonary hypertension in pulmonary histiocytosis X might be related to an intrinsic pulmonary vascular disease, in which the pulmonary circulation is involved independent of small airway and lung parenchyma injury.     

Clinico-epidemiological features of pulmonary histiocytosis X.

OBJECTIVE: To define the clinico-epidemiological features of pulmonary histiocytosis X in Japan. METHODS: A nationwide survey was carried out in 1997 using two questionnaires. RESULTS: The first questionnaire, which attempted to determine the number of patients during 1996, revealed that the number of patients treated at hospitals with 200 or more beds during the one-year period was estimated to be 160 (95% confidence interval: 140-180). The estimated crude prevalence among those aged 16 to 70 years was calculated as 0.27 and 0.07 per 100,000 population in males and females, respectively. The second questionnaire was concerned with the clinico-epidemiological features of the disease. Seventy-three histologically diagnosed patients were evaluated. It primarily afflicted younger adults, between the ages of 20 and 50, and showed a male predominance. Over 90% of the patients were smokers or ex-smokers and over 50% started smoking before 20 years of age, suggesting a strong association with cigarette smoking. Steroid therapy was applicable to 34% of the patients. In the patients who received steroid therapy, regression and stabilization were observed in 28% and deterioration in 36%. As for the patients for whom steroids were not required, remission occurred in 63% and progression in 10%. The ratio of remissions plus stabilization was higher in the patients who were not treated with steroids compared with those who required steroid therapy (p<0.05). CONCLUSION: In patients with pulmonary histiocytosis X therapeutic results obtained with steroids seemed not to be encouraging, although steroids are thought to be the most plausible treatment.     

Bronchogenic carcinoma in patients with pulmonary histiocytosis X.

Five cases of bronchogenic carcinoma were observed among 93 patients with pulmonary histiocytosis X (Hx). Mean age at the time of diagnosis of Hx was 42 years; on the average, cancer occurred 10.5 years later. All patients were smokers and continued to smoke heavily at the time of diagnosis of cancer. Comparison of the five cases associating Hx and lung carcinoma with a group of 88 control patients suffering from Hx alone suggested that smoking played the predominant role in the pathogenesis of cancer. In fact, among the four patients with Hx and carcinoma older than 45 years, tobacco consumption was significantly greater (64.7 +/- 37 pack-year, mean +/- SD) than that of the 15 control patients of the same age with only Hx (40.8 +/- 11.6, p less than 0.01). In light of this good correlation, the diagnosis of Hx strongly advocates stopping tobacco smoking and long-term medical follow-up.     

Data of broncho-alveolar lavage and pulmonary histiocytosis X

The data obtained from broncho-alveolar lavage in 12 cases of pulmonary histiocytosis X explored between 1978 and 1986 are reported. The usefulness of this simple and reliable examination to the diagnosis and follow-up is emphasized. The diagnosis, suggested by radiography of the chest, may be suspected on cytological findings of hypercellularity, macrophage alveolitis and eosinophilia. The occurrence of neutrophilic hypergranulocytosis indicates an unfavourable course towards fibrosis. An increase of cells marked with monoclonal OKT6 antibodies (70% of the cases in this series) contributes to the diagnosis of histiocytosis X and is a good indicator of granuloma activity during the follow-up period. Electron microscopy of the alveolar fluid often confirms the diagnosis by showing the specific organelle: the X granule (60% of the cases in this series), thus avoiding exploratory thoracotomy in many patients.     

Streptococcus equinus endocarditis in a patient with pulmonary histiocytosis X

Although Streptococcus equinus has been isolated from the human bowel in an appreciable percentage of the adult general population, it has only rarely been described as a human pathogen. Our report describes the occurrence of S. equinus endocarditis in a patient who had no history of pre-existing heart disease, but who showed evidence of a late-stage pulmonary histiocytosis X. Endocarditis resolved promptly after antibiotic treatment, but required aortic valve substitution. Abnormalities of the immune system that have been demonstrated in patients with histiocytosis X could explain the occurrence of endocarditis in this patient.     

Primary pulmonary hypertension in infancy: report of two autopsy cases

Two cases of unexplained plexogenic pulmonary arteriopathy in infancy were studied by patho-anatomical approach. The patients were boys, age 7 months and 2 years 2 months. Pulmonary arteries revealed Grade 3 and Grade 4 hypertensive changes, respectively, after Heath and Edwards' criteria. The configuration of the media of the pulmonary trunk suggested that though these cases were very young, pulmonary arterial pressure had been elevated since some time after birth.