Clinical characteristics, hospital outcome and prognostic factors of patients with ventilator-related pneumothorax.

BACKGROUND: Mechanical ventilation is a common cause of iatrogenic pneumothorax in intensive care units (ICU). Most of the patients with ventilator-related pneumothorax (VRP) have underlying lung diseases and is associated with increased morbidity and mortality. The prognostic factors of VRP are not clear. The objective of this study was to find the possible prognostic factors. METHODS: Analysis of retrospectively collected data of patients with pneumothorax induced by mechanical ventilation. Data were obtained concerning demographics, acute physiology and chronic health evaluation (APACHE) II score, organ failure, underlying diseases, interval between the start of mechanical ventilation and pneumothorax, arterial blood gas, respiratory parameters and patient outcomes. RESULTS: One hundred and twenty-four patients with VRP were included for analysis. The incidence rate of VRP was 0.4% (124/31,660), and the mortality rate was 77.4%. The patients with VRP had higher hospital mortality rate than that of mechanically ventilated patients without pneumothorax (77.4% vs. 13.7%, P<0.001) or patient with procedure-related pneumothorax (77.4% vs. 29.4%, P<0.001). Most cases of VRP occurred in the early phase of mechanical ventilation, and 8.9% of the patients had a later episode of pneumothorax on the opposite lung. The interval between two episodes of VRP was short, at a median time of 2 days. Cox regression analysis showed that tension pneumothorax (P=0.001), PaO2/FiO2<200 (P=0.002), and APACHE II score (P=0.008) were significantly associated with death. CONCLUSION: VRP patients with tension pneumothorax or PaO2/FiO2<200 had a higher risk of death. APACHE II scores were associated with mortality in the VRP patients with PaO2/FiO2≥200 mmHg.

Chronic myeloid leukemia initially presenting with spontaneous mediastinal hematoma and hemothorax.

Spontaneous mediastinal hematoma is rarely seen in hematologic malignancy. We report a case of chronic myeloid leukemia initially presenting with spontaneous hematoma and hemothorax. In addition to a detailed history, computerized tomography of the chest is important in analyzing whether an anterior mediastinal mass lesion is present. Magnetic resonance imaging is helpful in confirming the nature of a mediastinal hematoma. Trauma, vascular disease and coagulopathy should first be ruled out when making a diagnosis of spontaneous bleeding in the thorax. In our patient, the mediastinal hematoma regressed spontaneously after three months. Leukemia should be considered in the differential diagnosis of spontaneous mediastinal hematoma. In leukemia patients with spontaneous mediastinal hematoma, supportive observation and close follow-up may be better than surgery, unless massive hemorrhage or active bleeding in the thorax is suspected.

Ethambutol-induced psychosis: a case report.

Clinically, ethambutol (EMB)-induced psychosis is rare. In our review of the literature, most cases of antituberculosis agent-associated psychoses were caused by isoniazid (INH). We report the case of a 51-year-old man with suspected tuberculosis (TB) pleurisy. An anti-TB trial with INH, rifampicin and EMB was given initially. Dizziness, disorientation, and auditory and visual hallucinations developed after seven days of therapy. Laboratory examinations, including routine biochemistry tests, serum titer of antinuclear antibodies, cerebrospinal fluid analysis and computerized tomography of the head showed no abnormal findings. Following discontinuation of anti-TB agents, the psychiatric symptoms subsided. When the patient was challenged with EMB, the same psychiatric symptoms recurred, but resolved again after discontinuation of EMB. It is important to be aware that EMB can induce psychosis when anti-TB medications are prescribed.

Spindle cell carcinoma of the lung: a clinicopathologic presentation of three cases.

Three patients with spindle cell carcinoma located in the lower respiratory tract are presented, including cases of two monophasic and one biphasic tumor. On light microscopic examination, the spindle cell components of the tumors were histologically characterized by sheets of fusiform spindle cells that closely resembled a sarcoma. Keratin expression in the spindle cell components of these tumors, as shown by anti-cytokeratin antibody staining, demonstrated their epithelial nature. It is supposed that the spindle cell component displays a spectrum of phenotypes originating from epithelial cells with varying degrees of mesenchymal transformation. It is difficult to establish a diagnosis of this rare primary pulmonary malignancy prior to surgical intervention. A review of the literature allowed for a summary of the clinicopathologic characteristics of this tumor.

Multiple pleural nodules without effusion--a rare presentation of tuberculous pleurisy.

We report a rare case of tuberculous pleurisy presenting with multiple pleural nodules without associated effusion or parenchymal lung lesions. A 62-year-old man had multiple discrete pleural nodules in the right hemithorax on chest radiography without any clinical symptoms. Thoracoscopic biopsy of the pleural nodules revealed a caseous granuloma with acid-fast bacilli. The patient received antituberculous therapy, with resolution of tuberculomas on chest film within 2 months. To our knowledge, only two similar cases have been previously reported in the English literature, and our observation should lead to broadening of the spectrum of the differential diagnosis of multiple pleural nodules.

Intrathoracic extramedullary haematopoiesis complicated by massive haemothorax in alpha-thalassaemia.

Intrathoracic extramedullary haematopoiesis (EMH) is a rare entity that is usually asymptomatic. A 44 year old man with alpha-thalassaemia is described who developed dyspnoea and massive left sided haemothorax. The haemoglobin disorder was established by Hgb H staining and haemoglobin electrophoretic studies. The DNA analysis revealed it to be a case of double heterozygous terminal codon mutation with the genotype alphaalphaCS/alphaalphaT. Computed tomographic scanning and magnetic resonance imaging of the thorax showed multiple paravertebral masses which were found by thoracoscopic biopsy to be extramedullary haematopoiesis. Although no additional sclerosing pleurodesis or low dose radiation therapy was given, the lung expanded well and there has been no recurrence of haemothorax to date.