Levels of paraoxonase, an index of antioxidant defense, in patients with active sarcoidosis.

OBJECTIVE: Oxidative mechanisms are currently discussed as playing a crucial role in the genesis of inflammatory lung diseases. We aimed to evaluate the oxidant-antioxidant balance in the pathogenesis and activity of sarcoidosis and to search if the change in the level of PON can be taken as an activity marker. METHODS: 26 active sarcoidosis subjects aged 41.3+/-12.9 years, 37 inactive subjects aged 39.6+/-11.7 years and 48 control subjects aged 48.9+/-2.5 years were recruited in our study. Malondialdehyde (MDA), paraoxonase1 (PON1) and oxidized low density lipoprotein (oxLDL) levels in serum were analyzed by spectrophotometric, kinetic, and ELISA methods, respectively. RESULTS: PON1 levels were significantly lower in the active disease state than both the inactive form and control groups. MDA levels were significantly higher in active sarcoidosis than both the inactive disease and control groups, and oxLDL levels were significantly higher in the active disease group than the inactive group and control group. The level of PON1 in the inactive disease group is not significantly different from the control group while the oxLDL and MDA levels of inactive group is significantly higher than the control group (p<0.001). There was a negative correlation between the PON1 activities and MDA values in both active and inactive groups (p=0.008). CONCLUSION: Oxidative stress increases in sarcoidosis might be due to both increase in lipid peroxidation and decrease in antioxidant status (PON1) and the relationship between oxidative status and the activation of the disease should be discussed by comparing the previously known activation criteria.

Clinical value of mediastinoscopy in the diagnosis of sarcoidosis: an analysis of 68 cases.

Mediastinoscopy was performed for confirmation of the diagnosis in 68 patients who were suspected clinically and radiologically of having sarcoidosis. In 66 of 68 cases in which mediastioscopy was performed a diagnosis was attained. In 35 cases, endobronchial biopsy was performed by bronchoscopy. In only 5 of these (14.2 %) was the diagnosis of sarcoidosis confirmed. The sensitivity of mediastinoscopy was remarkably superior compared with that of endobronchial biopsy. No complication developed with either mediastinoscopy or endobronchial biopsy. In Turkey, mediastinoscopy without any complication costs about 650 USD while bronchoscopy and endobronchial biopsy cost about 150 USD. In our study in which we looked for a histological confirmation -- in the cases suspected of sarcoidosis -- mainly through mediastinoscopy and rarely through other methods (i.e., endobronchial biopsy in one case, skin biopsy in another), we did not come up with a different diagnosis. Therefore, patients suspected of having sarcoidosis should undergo a careful clinical, laboratory, and radiologic examination; they should be under continuous close observation; when necessary (e.g., skin and lip biopsy), the tissue diagnosis should be made by other methods, but if there is the possibility of a disease such as tuberculosis and lymphoma, mediastinoscopy should be performed. The diagnosis of stage 3 sarcoidosis is difficult. For diagnosis, sometimes videothoracoscopy or explorative thoracotomy may be necessary. However, in all our 3 cases with stage 3, we reached the diagnosis of sarcoidosis by the less invasive and less expensive method of mediastinoscopy. Despite our small number of cases, we believe that mediastinoscopy is a very important instrument for diagnosis of stage 3 sarcoidosis.

Cerebral tuberculosis mimicking intracranial tumour.

Cerebral tuberculoma is a rare entity and is one of the causes of intracerebral mass lesions. A rapid diagnosis based on pathological findings improves its prognosis. We describe two cases where the tuberculoma was located in the cavernous sinus and prepontine cistern, respectively. The first case was a 36-year-old man who was admitted with progressive headache, left ptosis and diplopia. Computed tomography showed a solid enhancing mass in the left cavernous sinus. Diagnosis of meningioma was proposed and a left pterional craniotomy was performed. Histopathological examination revealed granulomatous inflammation with areas of caseation necrosis. The second case was a 20-year-old man who presented with headache, new-onset strabismus, diplopia, malaise, weight loss and low-grade fever. The lesion mimicked an aggressive meningioma on imaging. The patient was operated for primary diagnosis of cerebral tumour. The histopathological examination of the excised lesion revealed a tuberculoma. Although the incidence of tuberculosis is decreasing, a high index of suspicion must be maintained for the diagnosis of intracranial masses in the presence of risk factors for tuberculosis.