Antithyroid drug-induced agranulocytosis complicated by pneumococcal sepsis and upper airway obstruction.

Streptococcus pneumoniae is a rare pathogen of sepsis in patients with antithyroid drug-induced agranulocytosis. We herein describe a case of antithyroid drug-induced agranulocytosis complicated by pneumococcal sepsis and upper airway obstruction. A 27-year-old woman who was previously prescribed methimazole for nine months presented with a four-day history of a sore throat. She nearly choked and was diagnosed with febrile agranulocytosis. She was successfully treated with intubation, intravenous antibiotics and granulocyte colony-stimulating factor. Her blood cultures yielded S. pneumoniae. Emergency airway management, treatment of sepsis and the administration of granulocyte colony-stimulating factor can improve the clinical course of antithyroid drug-induced pneumococcal sepsis in patients with airway obstruction.

Inhalation of urokinase-type plasminogen activator reduces airway remodeling in a murine asthma model.

The airway remodeling that occurs in asthma is characterized by an excess of extracellular matrix deposition in the submucosa, hyperplasia/hypertrophy of smooth muscle, goblet cell metaplasia, and accumulation of fibroblasts/myofibroblasts. The urokinase-type plasminogen activator (uPA)/plasmin system participates in pericellular proteolysis and is capable of directly degrading matrix components, activating latent proteinases, and activating growth factors. In a mouse ovalbumin (OVA) asthma model, we increased plasminogen activator activity in the lung by administering exogenous uPA or by using mice genetically deficient in the uPA inhibitor plasminogen activator inhibitor-1 (PAI-1) to assess the role of this system in asthma pathogenesis. After intraperitoneal OVA sensitization, mice inhaled OVA plus uPA (500 IU/mouse) or saline by ultrasonic nebulization for 3 wk. When studied 24 h after the final exposure, the groups with upregulated plasmin activity had significantly reduced subepithelial fibrosis within the airway walls and had decreased airway hyperresponsiveness (AHR) to methacholine. Morphometric analysis showed that subepithelial wall thickening of the bronchi (subepithelial area ratio) was also reduced, as were collagen and alpha-smooth muscle actin. Upregulation of plasmin activity also increased the level of hepatocyte growth factor activity in bronchoalveolar lavage fluid, whereas the release of transforming growth factor-beta was decreased. The administration of uPA 1 wk after the last OVA inhalation also significantly reduced lung hydroxyproline content and AHR. These results show that enhancing uPA/plasmin activity lessens the airway remodeling in a murine asthma model.

Continuous positive nasal airway pressure decreases levels of serum amyloid A and improves autonomic function in obstructive sleep apnea syndrome.

BACKGROUND: Obstructive sleep apnea syndrome (OSAS) is associated with the pathogenesis of cardiovascular disease, and inflammation and autonomic dysfunction. We investigated levels of serum amyloid A (SAA), a marker of inflammation, as well as autonomic nervous activity and pulse wave velocity (PWV) before and after nasal continuous positive airway pressure (nCPAP) therapy in patients with obstructive sleep apnea. METHODS AND RESULTS: We separated 116 patients who were diagnosed with OSAS by polysomnography according to the apnea hypopnea index (AHI) into the following groups: Group 1 without or with mild OSAS (AHI<20, n=35), Group 2 with moderate OSAS (20==40, n=46). Serum level of SAA (p<0.05), brachial-ankle PWV (p<0.05) and BP (p<0.005) were significantly higher in Group 3 than in Group 1. Autonomic nervous activity assessed by autoregressive spectral analysis of heart rate variability showed that high frequency (HF) power, an indicator of vagal activity, was decreased in Groups 2 and 3 (p<0.05) and that low frequency/HF, an indicator of sympathetic activity, was increased in Group 3 (p<0.05). After 3 months of nCPAP therapy in Group 3 (n=38), SAA (p<0.05), PWV (p<0.001) and BP (p<0.05) were significantly decreased. CONCLUSION: Markers of inflammation and autonomic dysfunction are increased in patients with OSAS, and nCPAP might help to reduce these risk factors for cardiovascular diseases.

Diffuse periairway thickening in patients with Mikulicz disease.

A 70-year-old woman presented with dry mouth, bilateral swelling of the eyelids, and abnormal taste and smell sensations that had persisted for 3 years. She was diagnosed with Mikulicz disease and presented with dyspnea on exertion afterwards. Chest computed tomography and magnetic resonance imaging showed wall thickening of the trachea and bilateral bronchus. Transbronchial needle aspiration showed lymphoproliferative lesion in the tracheobronchus. The patient was treated with corticosteroid, which improved all of her clinical symptoms, computed tomography, and magnetic resonance findings. In this case, we presented a rare condition of coexistent Mikulicz disease with tracheobroncial wall thickening caused by lymphoproliferation without lesions in small airways or lung.

Inhalation of sphingosine kinase inhibitor attenuates airway inflammation in asthmatic mouse model.

Sphingosine 1-phosphate (S1P) produced by sphingosine kinase (SPHK) is implicated in acute immunoresponses, however, mechanisms of SPHK/S1P signaling in the pathogenesis of bronchial asthma are poorly understood. In this study, we hypothesized that SPHK inhibition could ameliorate lung inflammation in ovalbumin (OVA)-challenged mouse lungs. Six- to eight-week-old C57BL/6J mice were sensitized and exposed to OVA for 3 consecutive days. Twenty-four hours later, mice lungs and bronchoalveolar lavage (BAL) fluid were analyzed. For an inhibitory effect, either of the two different SPHK inhibitors, N,N-dimethylsphingosine (DMS) or SPHK inhibitor [SK-I; 2-(p-hydroxyanilino)-4-(p-chlorophenyl) thiazole], was nebulized for 30 min before OVA inhalation. OVA inhalation caused S1P release into BAL fluid and high expression of SPHK1 around bronchial epithelial walls and inflammatory areas. DMS or SK-I inhalation resulted in a decrease in S1P amounts in BAL fluid to basal levels, accompanied by decreased eosinophil infiltration and peroxidase activity. The extent of inhibition caused by DMS inhalation was higher than that caused by SK-I. Like T helper 2 (Th2) cytokine release, OVA inhalation-induced increase in eotaxin expression was significantly suppressed by DMS pretreatment both at protein level in BAL fluid and at mRNA level in lung homogenates. Moreover, bronchial hyperresponsiveness to inhaled methacholine and goblet cell hyperplasia were improved by SPHK inhibitors. These data suggest that the inhibition of SPHK affected acute eosinophilic inflammation induced in antigen-challenged mouse model and that targeting SPHK may provide a novel therapeutic tool to treat bronchial asthma.

Comparative inhibitory effects of cilostazol and ticlopidine on subacute stent thrombosis and platelet function in acute myocardial infarction patients with percutaneous coronary intervention.

We compared the effects of ticlopidine and cilostazol on the prevention of subacute stent thrombosis (SAT) in acute myocardial infarction (AMI) patients with stenting. We also analyzed the cause of the difference by measuring platelet aggregation activity. Consecutive patients who underwent successful stenting for AMI between March 2001 and March 2004 were analyzed. In addition to aspirin (100 mg/day), cilostazol (200 mg/day) was administered to 99 cases between March 2001 and May 2002 and ticlopidine (200 mg/day) was administered to 85 cases between June 2002 and February 2004. The incidence of SAT within four weeks after stenting was analyzed. Thirty-eight AMI patients were randomized and their platelet aggregation activity was measured using a laser-scattered aggregometer (18 cases in the cilostazol group and 20 cases in the ticlopidine group). SAT did not occur in the ticlopidine group while 5 cases (5.1%) of SAT occurred in the cilostazol group (P < 0.05). The inhibitory activity of cilostazol for ADP-induced platelet aggregation was lower than that of ticlopidine (P < 0.05). Cilostazol with aspirin after stenting in AMI patients showed more frequent SAT than ticlopidine with aspirin. One of the causes for this difference was speculated to be the weaker inhibitory activity of cilostazol for ADP-induced platelet aggregation.

Pulmonary artery stenosis due to external compression by a calcified pericardial band.

A 60-year-old male with exertional dyspnea was referred to our hospital. Right pulmonary artery stenosis due to external compression by a calcified band was diagnosed by echocardiography, computed tomography, and magnetic resonance imaging. Percutaneous transluminal angioplasty was conducted in vain due to vascular recoil and failure of stent delivery. Pulmonary bypass grafting was performed successfully. The surgery indicated a probable etiology of chronic pericarditis. This is an extremely rare case of adult pulmonary artery stenosis without a known history of congenital disease, constrictive pericarditis, tuberculosis, or surgery.