序文：

新型コロナウイルス感染症（COVID-19）患者の一部に認める罹患後症状は，新たな健康問題となっている．罹患後症状の特徴やQOLへの影響などに関する知見が集積されているが，国内の罹患後症状の診療状況はよくわかっていない．今回感染症専門医がいる医療機関を対象とし，COVID-19罹患後症状の診療の実情と課題を明らかにするためアンケート調査を行った．

対象と方法：

2024年1月18日から3月9日の期間に，全国の感染症専門医880名に各所属医療機関の状況についてWebアンケート調査を行った．質問数は最大24問で内容は，回答者の属性や背景，COVID-19罹患後症状の診療経験，COVID-19罹患後症状の患者の特徴，COVID-19罹患後症状の診療状況，医療機関職員のCOVID-19罹患後症状についてであった．

結果

全国47都道府県の465名より回答を得た（回収率52.8%）．所属施設は病院が324名で最多であった．回答者の所属施設のうちCOVID-19罹患後症状の診療を行っていたのは69.7%だが，罹患後症状の専門外来設置は11.2%であった．罹患後症状は18～64歳の世代が多いとした回答者が多かった．罹患後症状が3カ月もしくは12カ月以上続いた患者がいたと回答したのは，それぞれ80.5%，51.9%であった．3カ月以上症状が続く患者では抑うつや物忘れなど精神神経症状を示したという回答者が多かった．治療法に関しては薬物療法だけでなくリハビリテーションやカウンセリングも利用されていた．所属医療機関の職員で罹患後症状を有する者がいたと回答したのは27.4%で，その2/3で休職が必要であったとの回答であった．

考察

感染症専門医のいる多くの医療機関はCOVID-19診療に対応しているものの，COVID-19罹患後症状に対する専門外来の設置は限られており，長期的な経過観察と支援体制が課題である．また，医療従事者のCOVID-19罹患後症状も無視できない問題であり，職場復帰支援などの体制整備が求められる．

Amebic dysentery, caused by the protozoan Entamoeba histolytica, is a serious intestinal parasitic disease associated with a high mortality, second only to that associated with malaria among parasitic infections globally. This disease is marked by severe intestinal symptoms, including bloody diarrhea, which can lead to fatal dehydration, particularly in young children in under-resourced areas. Japan has reported a rise in the number of cases of amebic dysentery, partly due to transmission via sexual contact, changing the traditional perception that amoebiasis is a travel-related infection. Despite its inclusion in mandatory infectious disease reporting, the level of awareness among medical practitioners and limitations of the diagnostic methods available remain challenges, and fatalities are still reported. This paper reviews the diverse pathogenetic mechanisms, including internal (pathogen-related) and external (microbiota-related) pathogenic factors, that contribute to disease progression and persistence of E. histolytica. The cyst-trophozoite lifecycle is described, alongside modes of transmission and resistance mechanisms that enable the parasite to survive passage through the gastric environment and establish itself in the colon. In addition, recent insights into the complex interactions between E. histolytica and the gut microbiota have revealed a modulation of the pathogenesis, suggesting that alterations in the microbiota composition can have an impact on the response of the parasite to oxidative stress. Further research into the relationship between E. histolytica and gut microbiota could pave the way for innovative therapeutic strategies, offering potential advancements in infection control and sustained prevention efforts.

Mpox (formerly known as monkeypox) is caused by monkeypox virus (MPXV), a member of the orthopoxvirus genus of viruses. Historically, it is endemic to Central and West Africa. Since 2022, however, a sharp rise in the number of mpox cases has been reported from non-endemic regions such as Europe and the United States. As compared with the traditional cases of mpox reported from the endemic regions, the majority of the patients in the new cases of mpox from non-endemic regions are gay, bisexual, and/or people living with HIV (PLWH), and anogenital skin lesions are a predominant clinical feature. Herein, we report two cases of mpox in PLWH. While case 1 had typical anogenital skin rashes with hemorrhagic proctitis, case 2 manifested proctitis without a skin rash. MPXV was detected by polymerase-chain reaction of scrapings from the skin rash in case 1, and from an anal swab in case 2. Our cases highlight the fact that in the recent outbreak of mpox, proctitis could be the sole presenting feature. Clinicians should consider the possibility of mpox in patients presenting with proctitis, irrespective of the presence/absence of skin lesions.

A 52-year-old Chinese man who was a cook by occupation visited our emergency department complaining of left-sided chest pain, and was diagnosed as having left-sided hydropneumothorax by chest computed tomography. The hydropneumothorax resolved with chest drainage, but subsequently, he presented twice within a month with recurrent right hydropneumothorax. We suspected paragonimiasis, but failed to detect any parasite ova in either the feces or the pleural fluid, and finally confirmed the diagnosis of paragonimiasis by serology. On further history-taking, the patient admitted to having eaten raw mitten crabs. Paragonimiasis is often difficult to diagnose, and detailed history-taking and proactive testing are important.