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21.
Shahid Husain Kenneth McCurry James Dauber Nina Singh Shimon Kusne 《The Journal of heart and lung transplantation》2002,21(3):354-359
BACKGROUND: Nocardia is responsible for infection in both normal and immunocompromised hosts. Organ transplant recipients are increasingly recognized as a sub-group of immunocompromised patients in whom nocardia is an important pathogen. The frequency of nocardia in organ transplant recipients varies between 0.7% and 3%. Nocardia infection has largely been reported in heart, kidney and liver transplant recipients. Presentations of nocardia in lung transplant recipients have been restricted primarily to case reports. The present study reviews the clinical and epidemiologic characteristics of nocardia infection in lung transplant recipients at our institution. METHODS: A retrospective cohort study of 473 lung transplant recipients from January 1991 to November 2000 was done at a university hospital. Patient demographics, immunosuppressive regimen at the time of isolation of nocardia species, use of trimethoprim-sulfamethoxazole for Pneumocystis carinii prophylaxis, rejection episodes in the preceding 6 months, concurrent pathogens, site of infection, radiologic findings and treatment and outcome were recorded. RESULTS: Nocardia infection was found in 2.1% (10 of 473) of our lung transplant recipients. Median time of onset was 34.1 months after transplantation. Nocardia species included N farcinica in 30% (3 of 10), N nova in 30% (3 of 10), N asteroides complex in 30% (3 of 10) and N brasiliensis in 10% (1 of 10) of patients. Post-transplant diabetes was present in 50% (5 of 10) of patients. The primary indication for lung transplantation was emphysema in 40% (4 of 10). Native lung involvement was noted in 75% (3 of 4) of patients with single lung transplant. Breakthrough nocardia infection were noted in 6 patients who were receiving trimethoprim-sulfamethoxazole prophylaxis for P carinii pneumonia; all breakthrough isolates remained susceptible to trimethoprim-sulfamethoxazole. Overall mortality was 40% (4 of 10). All patients (3 of 3) with infection due to N farcinica, except 1 (1 of 7) with infection due to other nocardia species, died. Seventy-five percent (3 of 4) of deaths were attributable to nocardia infection. CONCLUSIONS: Nocardia infection tended to involve the native lung in single lung transplant recipients. Trimethoprim-sulfamethoxazole for P carinii prophylaxis at the doses given was not protective against nocardiosis in these patients. Infection with N farcinica was associated with poor outcome. Thus, species identification and extended courses of antibiotics based on antimicrobial susceptibility testing are important in management of these patients. 相似文献
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Cough and paradoxical vocal fold motion 总被引:8,自引:0,他引:8
Kenneth W. Altman MD PhD C. Blake Simpson MD Milan R. Amin MD Mona Abaza MD Ron Balkissoon MD Roy R. Casiano MD 《Otolaryngology--head and neck surgery》2002,127(6):501-511
OBJECTIVES: The differential diagnosis and treatment of patients with chronic cough, paradoxical vocal fold motion, and disordered breathing can be a challenge to most practicing otolaryngologists. Tracheobronchial (ie, asthma, bronchitis, and tracheal stenosis), laryngeal (ie, vocal fold paralysis and neoplasms), and rhinologic (ie, allergies and rhinosinusitis) etiologies are commonly diagnosed and treated effectively. However, occasionally one is faced with patients who are refractory to medical treatment and have no obvious rhinologic, laryngeal or pulmonary cause. STUDY DESIGN AND SETTING: We conducted a review of the literature. METHODS: We present a thorough review of the current medical literature exploring the complex neurologic mechanisms involved in the production of cough and the relationship between gastroesophageal reflux disease, vagal neurapathy, and paradoxical vocal fold motion. RESULTS: The diagnosis and successful treatment of chronic cough can be complex. It requires a thorough understanding of the neurologic mechanisms behind cough excitation and suppression. Successful treatment strategies include aggressive management of the patient's reactive airway disease, gastroesophageal reflux disease, and, in select cases, paradoxical vocal fold motion. This may involve a well-coordinated effort among pulmonologists, otolaryngologists, gastroenterologists, and speech pathologists. CONCLUSION: Gastroesophageal reflux disease, vagal neuropathy, and paradoxical vocal fold motion are additional causes of chronic cough and disordered breathing that need to be considered, in the absence of obvious laryngotracheal and/or rhinologic pathology. A high index of suspicion is essential in making the diagnosis and formulating an effective multidisciplinary treatment plan for these patients. 相似文献
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Kenneth K. H. Chao BS Eric Cheung BS William B. Armstrong MD Brian J. F. Wong MD 《Otolaryngology--head and neck surgery》2002,126(6):593
Objective: The study goal was to compare the laser spot size created using reflective and refractive micromanipulators with a CO2 laser and to determine the sensitivity of spot size to laser power. Study Design and Setting: A CO2 laser and operating microscope (400-mm focal length) was coupled to either a reflective (Cassegrain-like) or refractive micromanipulator. Laser spot size was determined by measuring the region of ablation created by laser irradiation of wood (dry tongue depressors), exposed photographic film, and agar gel using optical micrometry. Laser power varied from 0.5 to 20 W with pulse durations of 0.1 and 0.5 second. Results: The reflective micromanipulator demonstrated overall smaller spot sizes for a given laser power and lower incremental change in spot size with increasing power. The reflective design demonstrated less sensitivity to increases in laser power. Conclusions: Micromanipulator optical design can result in significant differences in laser spot size. The reflective device used in this study demonstrated less sensitivity to increasing laser power. (Otolaryngol Head Neck Surg 2002;126:593-597.) 相似文献
27.
Reductions in substance use tend to coincide with marriage, as both may occur during emerging adulthood. During the transition to marriage, it is possible that one's spouse may be the influence that causes the reduction in substance use. Data on participants (N = 471 couples) for this report are taken from a longitudinal study of early marriage. The objective of the current analysis is to determine if having a spouse who uses marijuana is associated with a greater likelihood of one's own use. Additionally, we are interested in spousal influence and cessation. The findings support spousal influence. Husbands are more likely to start using marijuana if their wives use marijuana, but the reverse is not true. Husbands also are more likely to stop using if their spouses do not use. During the transition into marriage, the drug use of one spouse does affect the other. However, this influence appears to be unidirectional, with wives influencing their husbands more often. 相似文献
28.
Psoriasis is a chronic inflammatory condition that often requires life-long treatment. Conventional therapies have not fully met the needs of psoriatic patients, because of limited efficacy, adverse effects with cumulative use, and patient inconvenience. In the past decade, biologic immunotherapies have become accepted treatments for psoriasis as a result of perceived efficacy and safety on the part of patients and practitioners. However, most data on these medications come from relatively limited short-term trials. In this review, we will focus on the available long-term data on the efficacy of the biologic agents. We will emphasize the strengths and weakness of the available data of the biologic agents that are Food and Drug Administration (FDA)-approved for the treatment of moderate to severe psoriasis (alefacept, efalizumab, * etanercept, infliximab, and adalimumab), with the inclusion of a newer agent currently under FDA evaluation (ustekinumab). 相似文献
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Few cases in the history of epidemiology and public health are more famous than John Snow's investigation of a neighborhood cholera outbreak in the St. James, Westminster, area of London in 1854. In this study Snow is assumed to have proven that cholera was water rather than airborne through a methodology that became, and to a great extent remains, central to the science and social science of disease studies. And yet, Snow's work did not satisfy most of his contemporaries who considered his proof of a solely waterborne cholera interesting but unconvincing. Uniquely, this paper asks whether the caution of Snow's contemporaries was reasonable, and secondly, whether Snow might have been more convincing within the science of the day. The answers significantly alter our understanding of this paradigmatic case. It does so in a manner offering insights both into the origins of nineteenth century disease analysis and more generally, the relation of mapping in the investigation of an outbreak of uncertain origin. The result has general relevance—pedagogically and practically—in epidemiology, medical geography, and public health. 相似文献