[Pulmonary Langerhans cell histiocytosis--evaluation of the disease activity and treatment response using PET-CT (SUV(max) Pulmo/SUV(max) Hepar index). Description of own experience and literature review]

Pulmonary Langerhans cell histiocytosis (LCH) manifests with dyspnoea and a cough with no significant expectoration, with spontaneous pneumothorax being the first symptom in some patients. The disease is caused by multiple granulomas in terminal bronchioles, visible on high resolution CT (HRCT) as nodules. During the further course of the disease, these nodules progress through cavitating nodules into thick-walled and, subsequently, thin-walled cysts. LCH may affect the lungs only or multiple organs simultaneously. Pulmonary LCH may continually progress or remit spontaneously. Treatment is indicated in patients in whom pulmonary involvement is associated with multi-system involvement or when a progression of the pulmonary lesions has been confirmed. To document the disease progression, examination of the lungs using HRCT is routinely applied. Increasing number of nodules suggests disease progression. However, determining the number of nodules is extremely difficult. Measuring radioactivity of the individual small pulmonary loci (nodules) using PET is not possible due to the high number and small size of the nodules. Our centre has a register of 23 patients with LCH; the pulmonary form had been diagnosed in 7 patients. A total of 19 PET and PET-CT examinations were performed in 6 of these patients. PET-CT was performed using the technique of maximum fluorodeoxyglucose accumulation in a defined volume of the right lung--SUV(max) Pulmo. In order to compare the results of examinations performed using the same and different machines over time as well as in order to evaluate pulmonary activity, the maximum fluorodeoxyglucose accumulation in a defined volume of the right lung (SUV(max) Pulmo) to maximum fluorodeoxyglucose accumulation in a defined volume of the liver tissue (SUV(max) Hepar) ratio (index) was used. The disease progression was evaluated using the SUV(max) Pulmo/SUV(max) Hepar index in the six patients with pulmonary LCH. The index value was compared to other parameters characterising the disease activity (HRCT of the lungs, examination of pulmonary function and clinical picture). The SUV(max) Pulmo/SUV(max) Hepar index correlated closely with other disease activity parameters. The traditional PET-CT examination is useful in detecting the LCH loci in the bone, nodes and other tissue but not in the presence of diffuse involvement of pulmonary parenchyma. Measuring the maximum fluorodeoxyglucose accumulation in a defined volume of the right lung and expressing this activity as the SUV(max) Pulmo/SUV(max) Hepar index appears to be a promising approach. Our initial experience suggests that the results obtained using this method correlate well with other parameters that characterise activity of pulmonary LCH. However, this is a pilot study and further verification is required.

[Non-invasive ventilation support in patients with acute exacerbation of chronic obstructive pulmonary disease (COPD)]

AIM

To verify that the use of noninvasive ventilatory support in acute exacerbation of chronic obstructive pulmonary disease leads to decreasing the number of deaths, shortening in-hospital stay and decreasing number of endotracheal intubations (ETI).

SETTING

The study was conducted at a respiratory department's ICU in 2002-2004.

METHODS

Patients hospitalized on ICU with acute exacerbation of COPD, respiratory acidosis and global respiratory failure were randomised into two groups. Patients in group A were treated by conservative medical therapy (oxygen, bronchodilator, corticosteroid), patients in group B received noninvasive ventilation with face mask. The parameters followed were: decrease in the number of deaths, shortening of ICU stay, reduction of ETI, faster improvement of breathing frequency, heart rate, pH, PaO2, PaCO2, lactate, dyspnoea symptom score and lung functions.

RESULTS

Each group consisted of 30 randomised patients. There were 10 intubated patients in group A, as opposed to 3 in group B (N = 60; P = 0.034). Average length of ICU stay was 9.8 days in group A and 7.1 days in group B (N = 60; P = 0.756). Mortality rate was identical in both groups: 3 patients survived, 7 patients died. We found faster decrease of breathing frequency after one hour of noninvasive ventilation in group B (28.3 +/- 7.1 vs. 24.6 +/- 6.3, N = 59, p = 0.03).

CONCLUSION

No difference was found in mortality rate. We observed decreasing of ETI rate with NIV. We found a tendency to shortening of ICU stay. There was faster improvement of breathing frequency after one hour of NIV.