免疫抑制状態患者におけるノロウイルス胃腸炎

日常遭遇するノロウイルス感染も免疫不全状態の患者さんにおいては様相を異にします。

8:44| "Norovirus Gastroenteritis in Immunocompromised Patients", a review article by Karin Bok from National Institutes of Health, Bethesda, Maryland.
Infectious gastroenteritis is a common, acute illness that is characteristically self-limiting, but it can become debilitating and life-threatening in immunocompromised patients. Noroviruses are major pathogens among the microbes associated with gastroenteritis in both immunocompetent and immunocompromised hosts. In the United States, noroviruses are the single most common cause of acute gastroenteritis in adults that results in a visit to the hospital emergency department, and they are second only to rotaviruses as a major cause of severe diarrhea in infants and young children. In developing countries, noroviruses are estimated to cause more than 200,000 deaths annually among children younger than 5 years of age. Noroviruses are increasingly recognized as an important cause of chronic gastroenteritis in immunocompromised patients, as reflected by the growing number of clinical case reports. A comparison of the known features of norovirus gastroenteritis in immunocompetent versus immunocompromised hosts highlights the potentially serious outcome of this illness in persons who cannot adequately clear the virus. The purpose of this review is to summarize recent developments in norovirus research that are relevant to the prevention and management of norovirus gastroenteritis in immunocompromised patients. Genetic features and emerging treatments are discussed.

注

• debilitating: 消耗性の
• second only to 〜: 〜に次いで
• relevant to 〜: 〜に関して

乳がん検診の効果

結論を言うと、マンモグラフィーによる検診は、進行癌を１人減らすためのNNTが12,500と非常に非効率だそうです。

6:04 | "Effect of Three Decades of Screening Mammography on Breast-Cancer Incidence" by Archie Bleyer from St. Charles Health System, Central Oregon.
The introduction of screening mammography in the United States has been associated with a doubling in the number of cases of early-stage breast cancer that are detected each year, from 112 to 234 cases per 100,000 women — an absolute increase of 122 cases per 100,000 women. Concomitantly, the rate at which women present with late-stage cancer has decreased by 8%, from 102 to 94 cases per 100,000 women — an absolute decrease of 8 cases per 100,000 women. With the assumption of a constant underlying disease burden, only 8 of the 122 additional early-stage cancers diagnosed were expected to progress to advanced disease. After excluding the transient excess incidence associated with hormone-replacement therapy and adjusting for trends in the incidence of breast cancer among women younger than 40 years of age, the authors estimated that breast cancer was overdiagnosed (i.e., tumors were detected on screening that would never have led to clinical symptoms) in 1.3 million U.S. women in the past 30 years. The authors estimated that in 2008, breast cancer was overdiagnosed in more than 70,000 women; this accounted for 31% of all breast cancers diagnosed.
These rusults suggests that screening is having, at best, only a small effect on the rate of death from breast cancer. (240 words / 109 sec = 132 wpm)
From NEJM Audio Summaries

注

• mammography: mæmɑ'grəfi アクセントの位置に注意
• concomitantly： 同時に　cf. concomitant chemoradiotherapy
• i.e. (latin: id est) = that is
• at best: よくても　cf. The best of men are but men at best.どんなに立派な人でも、所詮、人以上のものではない。◆ことわざ

再発性ライム病、再燃、それとも再感染？

0:51| "Differentiation of Reinfection from Relapse in Recurrent Lyme Disease" by  Robert Nadelman from New York Medical College, Valhalla.
Much controversy exists regarding whether recurrent Lyme disease is due to reinfection or relapse. These investigators used molecular typing of Borrelia burgdorferi isolates obtained from patients with culture-confirmed episodes of erythema migrans to distinguish between relapse and reinfection. The outer-surface protein C of B. burgdorferi which is expressed in early infection was found to be different at each initial and second episode. Apparently identical genotypes were identified on more than one occasion in only one patient, at the first and third episodes, 5 years apart, but different genotypes were identified at the second and fourth episodes. None of the 22 paired consecutive episodes of erythema migrans were associated with the same strain of B. burgdorferi on culture. These data show that repeat episodes of erythema migrans in appropriately treated patients were due to reinfection and not relapse.
In editorial, Allen Steere from Massachusetts General Hospital, Boston, writes that the issue of relapse versus reinfection has a broader context because of patient-advocacy groups that promote months or years of antibiotic therapy for “chronic Lyme disease.” Moreover, chronic Lyme disease has become a common diagnosis for medically unexplained pain or neurocognitive or fatigue symptoms, even when there is little or no evidence of previous B. burgdorferi infection. Even so, these patients are said to have persistent infection, which can be suppressed only with months or years of antibiotic therapy, and the therapy must be restarted when symptoms recur. As concluded by the Infectious Diseases Society of America, there is no evidence of persistent B. burgdorferi infection in human patients after recommended courses of antibiotic therapy. Although B. burgdorferi infection may persist for years in untreated patients, the weight of evidence is strongly against persistent infection as the explanation for persistent symptoms in antibiotic-treated patients with Lyme disease.  (317 words / 151 sec = 126 wpm)

この論文とは関係ありませんが、ライム病つながりで。上掲本に、下の論文にあるライム病とトカゲの関係の話が出てきます。感染症の治療は、患者、病原体、薬剤のトライアングルで考えますが、公衆衛生学的な対策は生態系全体を考慮に入れなければならないことを実感させる実例です。

• Lane RS, Quistad GB. Borreliacidal factor in the blood of the western fence lizard (Sceloporus occidentalis).  J Parasitol. 1998 Feb;84(1):29-34. 

NEJM Audio Summary - Nov 8, 2012

先日３例目の感染者が公表された新型コロナウイルス感染症の記事です。

7:37| "Isolation of a Novel Coronavirus from a Man with Pneumonia in Saudi Arabia", by Ali M. Zaki from the Dr. Soliman Fakeeh Hospital, Jeddah, Saudi Arabia. On June 24, a 60-year-old man died of progressive respiratory infection in Saudi Arabia. The previously unknown coronavirus was isolated from the sputum of a man who had presented with acute pneumonia and subsequent renal failure with a fatal outcome. The virus (called HCoV-EMC) replicated readily in cell culture, producing cytopathic effects of rounding, detachment, and syncytium formation. The virus represents a novel betacoronavirus species. The closest known relatives are bat coronaviruses. In this ariticle, the clinical data, virus isolation, and molecular identification are presented. The clinical picture was remarkably similar to that of the severe acute respiratory syndrome (SARS) outbreak in 2003 and reminds us that animal coronaviruses can cause severe disease in humans.
 In editorial, Larry Anderson, from Emory Children Center, Atlanta, Georgea writes that The global community was apparently not aware of the first case of HCoV-EMC infection until it was reported on ProMED, a website for monitoring emerging diseases, on September 20, approximately 3 months after the patient died. Luckily, there have been no new reports of cases since September 22, but local surveillance should continue. With no evidence of human-to-human transmission, the WHO currently recommends no heightened global surveillance for this virus but continued “routine surveillance for early detection and rapid response of all potential public health threats.” However, such cases provide an opportunity to reconsider response strategies. (255 words / 124 sec = 123 wpm)

NEJM Audio Summary - Nov 1, 2012

今回は、アタマジラミの治療に関する論文。日本では、ピレスロイドの１つ、フェノトリンを含むスミスリンパウダーかスミスリンシャンプーを使用するが、耐性を獲得した虫が多い欧米では、代替え治療としてイベルメクチンの内服、外用も行われるらしい。内服治療に関しては、以前にNEJMでも論文が出ている。今回は外用の効果についてです。

0:56 | "Topical 0.5% Ivermectin Lotion for Treatment of Head Lice" by David Pariser from Eastern Virginia Medical School, Norfolk. New treatments for head lice are needed. Two trials involving 765 patients investigated the efficacy and safety of a single application of a new 0.5% ivermectin lotion formulation as compared with vehicle control, an identical formulation without ivermectin, in patients with head-louse infestation. In the intention-to-treat population, significantly more patients receiving ivermectin than patients receiving vehicle control were louse-free on day 2 (94.9% vs. 31.3%) and day 15 (73.8% vs. 17.6%). The frequency and severity of adverse events were similar in the two groups. A single, 10-minute, at-home application of ivermectin was more effective than vehicle control in eliminating head-louse infestations at 1, 7, and 14 days after treatment. 

In editorial Olivier Chosidow from Hôpital Henri-Mondor, Créteil, France asks "How should head-louse infestation be managed?". With good comparative-effectiveness research still lacking, indirect comparisons support the 2010 American Academy of Pediatrics recommendations to use 1% permethrin or pyrethrin insecticide as first-line therapy. If resistance in the community has been proven or live lice are present 1 day after the completion of treatment, a switch to malathion may be necessary. Other options include wet combing or treatment with dimethicone or other topical agents, depending on the availability of the agents in the country. Nit removal is useful. Ivermectin should be the last choice, whether topical (for still-infested persons) or oral (especially for mass treatment). Management should also include more frequent checking for head-louse infestation in families and schools. (273 words / 136 sec = 120 wpm)