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991.
Codeine phosphate-induced hypersensitivity syndrome   总被引:2,自引:0,他引:2  
OBJECTIVE: To report a case of drug-induced hypersensitivity syndrome related to codeine phosphate. CASE SUMMARY: A 19-year-old Japanese man was prescribed codeine phosphate 10 mg 3 times daily and several other drugs for cold symptoms. About 20 days later, an erythematous, maculopapular rash appeared and progressed to erythroderma; a spiking fever also developed. He had splenomegaly and generalized lymphadenopathy on admission. Laboratory examinations showed atypical lymphocytosis, eosinophilia, and increased liver enzyme values. The platelet count slowly decreased after admission. The increased numbers of megakaryocytes in bone marrow and platelet-associated immunoglobulin (Ig) G antibodies in serum were compatible with a diagnosis of immune thrombocytopenic purpura. A significant increase in IgG antibodies to human herpesvirus 6 (HHV6) and transient viremia were helpful in diagnosing hypersensitivity syndrome. The results of patch tests were positive for codeine phosphate. An objective causality assessment revealed that an adverse drug event was probable. DISCUSSION: Codeine is an opioid analgesic. Severe adverse cutaneous reactions rarely occur. As of March 3, 2004, our case is, to our knowledge, the first report of hypersensitivity syndrome attributed to codeine phosphate. Drug-induced hypersensitivity syndrome is an acute, potentially life-threatening, idiosyncratic adverse reaction caused mainly by aromatic anticonvulsants. It is characterized by the triad of fever, skin rash, and internal organ involvement. Reactivation of HHV6 is involved in the pathogenesis of this syndrome and may have also caused the immune thrombocytopenic purpura in our patient. CONCLUSIONS: Codeine phosphate may rarely be associated with hypersensitivity syndrome. Clinicians should be aware that the potentially fatal syndrome can be caused by various drugs.  相似文献   
992.
993.
BACKGROUND: Methylprednisolone, dexamethasone, and other glucocorticoids have been found effective against nausea and vomiting induced by chemotherapy and surgery. Although the specific 5-hydroxytriptamine3 (5-HT3) receptor antagonists such as ondansetron and ramosetron are used as antiemetics, reports show that the use of 5-HT3 receptor antagonists with some glucocorticoids brings additional effects. Glucocorticoids are reported to be antiemetic. The effect of glucocorticoids on 5-HT3 receptor, however, has not been well characterized. This study was designed to examine whether dexamethasone and methylprednisolone had direct effects on human-cloned 5-HT3A receptor expressed in Xenopus oocytes. METHODS: Homomeric human-cloned 5-HT3A receptor was expressed in Xenopus oocytes. The authors used the two-electrode voltage-clamping technique to study the effect of methylprednisolone and dexamethasone on 5-HT-induced current. RESULTS: Both dexamethasone and methylprednisolone concentration-dependently attenuated 5-HT-induced current. Dexamethasone inhibited 2 microm 5-HT-induced current, which was equivalent to EC30 concentration for 5-HT3A receptor, with an inhibitory concentration 50% of 5.29 +/- 1.02 microm. Methylprednisolone inhibited 2 microm 5-HT-induced current with an inhibitory concentration 50% of 1.07 +/- 0.15 mm. The mode of inhibition with either dexamethasone or methylprednisolone was noncompetitive and voltage-independent. When administered together with the 5-HT3 receptor antagonists, ramosetron or metoclopramide, both glucocorticoids showed an additive effect on 5-HT3 receptor. CONCLUSION: The glucocorticoids had a direct inhibitory effect on 5-HT3 receptors. The combined effect of glucocorticoids and the 5-HT3 receptor antagonists seems additive.  相似文献   
994.
BACKGROUND: Left ventricular assist system technologies are currently being developed as effective alternatives to cardiac transplantation. In this study, in vivo testing of the Arrow International CorAide left ventricular assist system was conducted to determine its preclinical readiness based on demonstrated system performance and biocompatibility. METHODS: Arrow International CorAide blood pump assemblies were implanted in 7 calves for 1-month (n = 4) and 3-month (n = 3) durations without the use of chronic anticoagulation therapy. Hemodynamic performance, physiologic pump control, end-organ function, and device-related adverse events were evaluated during the studies and at autopsy. RESULTS: Hemodynamics were stable in all cases with a mean pump flow of 4.1 +/- 0.8 L/min and a mean arterial pressure of 101 +/- 4 mm Hg. In all calves, renal and hepatic function remained normal with no incidence of hemolysis, infection, bleeding, or embolism. The CorAide physiologic control algorithm demonstrated appropriate pump speed and flow adjustments in response to physiologically induced inputs, and the system's external electronic components demonstrated no hardware or software malfunction. All 7 cases were sacrificed electively. Autopsy revealed no sign of end-organ disease on gross and histologic examinations, and no device failure, malfunction, or mechanical wear of the pump blood-bearing surfaces was found. CONCLUSIONS: The Arrow CorAide left ventricular assist system demonstrated effective pump performance and good biocompatibility with no incidence of device-related adverse events. This system has completed its preclinical readiness testing and is approved for clinical trials in Europe in 2003.  相似文献   
995.
Heme oxygenase-1 (HO-1) is induced by oxidative stress and is thought to confer protection against oxidative tissue injuries. HO-1 catalyzes the conversion of the heme moiety of hemeproteins, such as hemoglobin, myoglobin, and cytochrome P450, to biliverdin, liberating carbon monoxide (CO) in the process. CO reacts with hemoglobin to form carboxyhemoglobin. In this study, to examine the effect of anesthesia and/or surgery on endogenous CO production, we measured the amount of exhaled CO and the arterial carboxyhemoglobin concentration of patients who underwent surgery under general or spinal anesthesia. Both CO and carboxyhemoglobin concentrations were significantly larger on the day after surgery than during the preoperative period (P < 0.05) and in the recovery room (P < 0.05), regardless of anesthesia. However, neither index differed between general and spinal anesthesia. These results suggest that oxidative stress caused by anesthesia and/or surgery may induce HO-1, which catalyzes heme to produce CO, leading to increased exhaled CO concentration.  相似文献   
996.
We report 2 cases of hypersensitivity to an epinephrine preparation in local anesthetics which were found by skin tests for local anesthetics. Both patients had uncomfortable episodes to local anesthetics at dental treatment. In both cases, the skin tests showed positive reactions to 2% lidocaine with 1:80,000 epinephrine. Furthermore drug lymphocyte stimulation test revealed positive reaction to epinephrine hydrochloride, epinephrine bitartrate in case 1, whereas in case 2, the drug lymphocyte stimulation test showed positive response to epinephrine bitartrate. Attention should be paid to exogenous epinephrine preparations that have the potential to induce hypersensitivity during dental treatment.  相似文献   
997.
Disassembly of bipolar cups with a self-centering system occurred in six patients (seven hips; five women, one man) and the cause of the failure was evaluated. The mean age of the patients at the time of arthroplasty was 49.7 years (range, 27-85 years), and mean weight was 48.4 kg (range, 37-65 kg). The mean time to failure was 7.5 years (range, 4.8-9.2 years). Before failure, all implants functioned well and none of the patients had sustained trauma. Retrieval study showed that the cause of failure of the locking mechanism with a self-centering system was severe polyethylene abrasion at the rim attributable to impingement and deformity of the locking ring. After the locking ring detached, the inner head dislocated from the outer head resulting in a varus position of the outer head in the acetabulum. If the deformed locking ring did not detach, the inner head could dislocate, with the varus outer head remaining in the acetabulum. The incidence of this failure was 11%. This disassembly is not a rare occurrence numerous years after a well-functioning bipolar hemiarthroplasty, even with the self-centering system.  相似文献   
998.
Reactive angioendotheliomatosis of the intestine   总被引:1,自引:0,他引:1  
We present a case of reactive angioendotheliomatosis (RAE) of the colon, featuring intravascular proliferation of endothelial cells with histologic resemblance to glomeruloid hemangioma. A 19-year-old Japanese male with an anal fistula was diagnosed endoscopically with Crohn's disease. Six months later, he was hospitalized for fever and abdominal pain. Emergency resection of ileocecum and splenic flexure of the colon was undertaken to control massive intestinal hemorrhage, and in all parts of the resected colon, foci of many small vessels with intravascular proliferation of endothelial cells were noted throughout the layers. Moreover, solid proliferation of endothelial cells was seen in the submucosa at the base of open ulcers. Two small granulomas, compatible with Crohn's disease, were also evident in the muscle layer of the terminal ileum. No other hemangiomas or hemangioma-like structures were observed with CT scans, and the vascular lesions were histologically diagnosed as RAE. The pathogenesis of this disorder is unknown, and most cases occur in skin with systemic disease. The present case might thus be a first case of RAE of the intestine without cutaneous involvement. Whether there is a relation with coexistent enteritis suggestive of Crohn's disease needs to be clarified.  相似文献   
999.
The authors report a case of Currarino triad with a combination of anterior sacral meningocele and mature teratoma, sacral body deformity, anorectal stenosis, and tethered cord. A newborn girl suffered from vomiting, abdominal distension and constipation. Initially, a diverting colostomy was performed at the age of one month. 7 months later, at the age of 8 months, we performed posterior sagittal anorectoplasty (PSARP): As a result, extirpation of teratoma, excision of meningocele, untethering of the spinal cord, and anorectoplasty were achieved simultaneously without complication. We suggest the use of an MRI to specify the presence of anosacral and spinal cord anomalies in patients with intractable constipation and we recommend combined pediatric and neurosurgical assessment and management for all cases of Currarino triad.  相似文献   
1000.
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