インフルエンザウイルスの検出において銀増幅により感度を高めたイムノクロマト法（IC 法）の有用性を検討した．2014 年12 月から2015 年1 月までに長崎大学病院においてインフルエンザ抗原検査が依頼された検体を対象に，従来法と銀増幅IC 法で測定を行い，結果を比較した．解析対象となった203 検体に対して両検査法の一致率は94.1%（191/203）であった．陽性率は銀増幅法15.8%（32/203），従来法10.8%（22/203）であり前者で有意に高かった．本検討では従来法の結果のみを依頼者へ返却し，その結果に基づいて実施される診療を観察することにより，従来法と銀増幅IC 法との結果の乖離が診療に与えうる影響を検討した．銀増幅IC 法が陽性となった32 症例（従来法陽性21 症例，陰性11 症例）が実際はインフルエンザであったとして，それらを従来法の結果によって2 群に分類して比較検討を行った．銀増幅IC 法が陽性となった32 症例のうち，ノイラミニダーゼ阻害薬が投与されたのは，従来法が陰性の場合には9.1%（1/11）であったのに対し，陽性の場合には90.5%（19/21）と後者で有意に高かった．抗菌薬が投与された割合は，従来法が陰性の場合45.5%（5/11）であったのに対し，陽性の場合には19.0%（4/21）と後者で低い傾向であった．院内感染対策に与えうる影響についても検討したところ，銀増幅IC 法が陽性であったにもかかわらず従来法が陰性となった6 名はインフルエンザの診断に至らず，適切にノイラミニダーゼ阻害薬が投与されないまま入院もしくは入院継続となった． 銀増幅IC 法により高感度にインフルエンザウイルスを検出できれば，適切なノイラミニダーゼ阻害薬の投与や不要な抗菌薬投与の抑制，および適切な感染対策の実施に貢献できる可能性が示唆された．

敗血症は，世界各国で死亡率の高い疾患である．敗血症治療において，早期に原因菌を同定し，適切な抗菌薬を投与することが救命の鍵を握るものの，血液培養を初めとする従来の細菌同定法は迅速性に乏しい．本研究では，血液培養から分離頻度の高い黄色ブドウ球菌，表皮ブドウ球菌，腸球菌（Enterococcus faecalis），大腸菌，肺炎桿菌，緑膿菌，エンテロバクター（Enterobacter cloacae）の迅速同定法として，cell-direct PCR（cdPCR）/核酸クロマトグラフィー法を開発した．まず我々は，感染に対する初期の生体防御反応である好中球の細菌貪食作用に着目し，本法により好中球内の細菌DNA の検出を試みた．in vitro で健常人の白血球に各種細菌を貪食させ，cdPCR 法を適用したところ，PCR チューブに白血球を乾燥固定した状態で好中球内の細菌DNA が増幅され，NALF 法により菌種を迅速に同定することができた．次に健常人の血液と大腸菌，もしくは黄色ブドウ球菌を共培養することで菌血症の状態を模倣し，cdPCR/核酸クロマトグラフィー法を適用した結果，血液検体から直接，4.5 時間以内に標的菌を検出できた．また，培養法と検出感度を比較した結果，検体によっては培養法で陰性（10 コロニー形成単位/mL 以下）であってもcdPCR/核酸クロマトグラフィー法では陽性結果が得られた．さらに白血球に貪食された細菌数をリアルタイムPCR 法で概算した結果，少なくとも白血球20 万個あたり10¹ オーダーの細菌が貪食されていればcdPCR/核酸クロマトグラフィー法で陽性結果が得られることが示唆された．これらの結果は，cdPCR/核酸クロマトグラフィー法は微量な細菌DNA を特異的に検出できる可能性を示しており，敗血症原因菌の迅速同定法としての臨床応用が期待される．

We report herein on a Japanese patient with Ancylostoma ceylanicum infection on returning from Papua New Guinea who was diagnosed by molecular identification of the parasite eggs. The patient was a 26-yearold male who stayed at Lorengau city, Manus Province, Papua New Guinea for 2 years. He was providing guidance about agricultural technology and doing his work barefoot with local residents. After returning from Papua New Guinea, hookworm eggs were detected during a feacal examination as part of a health checkup and he was referred to our hospital for further examination and treatment. He had not had any health problem such as dermatitis, fever or respiratory or abdominal symptoms during his stay in Papua New Guinea. On admission to our hospital, the laboratory data revealed a normal WBC count with hypereosinophilia (20.9%). Feacal examination with the Kato cellophane thick smear technique showed 220 eggs/g feces of hookworm eggs. For species identification, DNA extracted from eggs obtained by the floatation method with saturated sodium chloride solution were subjected to a PCR assay specific for the mitochondrial cytochrome c oxidase subunit 1 (Cox1), ribosomal internal transcribed spacers (ITS) -1 and ITS-2 genes. The cox1 region was very close to, and ITS-1/ITS-2 region were shown to have a 100% sequence identity with the A. ceylanicum sequence. The patient was treated with a single dose of pyrantel pamoate (10 mg/kg). No eggs were found in further feacal examinations and the eosinophilia improved to a normal level at 4 weeks after the treatment. Eosinophilia in returning travelers is one of the clues for suspicious helminth infections even though the patients are asymptomatic. Physicians should recognize the possibilities of helminth infection including hookworm and proceed to appropriate parasitological examinations considering the countries the travelersʼ have visited, their living environment, their activities while there, and the endemic parasite species.

A 59-year-old man was referred to our hospital with acute respiratory failure. He had returned from Hong Kong one week before the symptoms appeared. Although avian influenza has been reported in China since 2013, a pharyngeal swab revealed influenza A (H1N1) pdm09 instead of influenza A (H7N9). The patient required intensive care including extracorporeal membrane oxygenation and continuous hemodiafiltration. Emerging and re-emerging infectious diseases are globally endemic. However, intensive care systems in Japan might not be sufficient to care for patients presenting with acute respiratory failure after returning from abroad. An optimal system for the acceptance and intensive care of such patients should be considered.

A 70-year-old man, with abnormalities on his chest X-ray, was admitted to our hospital. He had a history of hypersensitivity pneumonitis and tuberculosis, but he was not being treated with any medication, including steroids, at the time of admission. On admission, chest computed tomography (CT) revealed a cavity with consolidation in the left upper lobe and ground glass opacity in the right upper and lower lobes of the lungs. Cunninghamella bertholletiaewere isolated from the CT-guided aspiration specimen. After three weeks of treatment with liposomal amphotericin B and itraconazole, the chest CT showed minor improvement in the cavity. After bronchial arterial embolization, a left upper lobectomy was performed. Histopathological examination of the resected left upper lobe revealed fungal hyphae in the cavity, which was surrounded with fibrosis, and small, necrotizing granulomas. Thus, the patient was diagnosed as having pulmonary C. bertholletiae infection, arising in a residual tuberculous cavity. Twelve days after surgery, respiratory failure developed, and progressed rapidly, despite administration of steroid pulse therapy and mechanical ventilation. The patient died one month after the surgery.

A previously healthy 47-year-old male car driver visited our hospital because of 4-day history of high fever and multiple arthralgia of the major joints. Laboratory data showed a high level of CRP (25.1mg/dL), severe thrombocytopenia (18,000/μL), and liver dysfunction (AST 320U/L, ALT 772U/L).
Physical examination revealed polyarthritis of the shoulders, elbows, knee joints, ankles, and hip joints. A pinkish macro rash was visible on the lower abdomen, lower extremities, and foot arches. Small black crusts on his right index finger with little discharge were incidentally found, and the patient reported that he had been bitten by his dachshund one day before the onset of the fever. Soon after admission, he was given platelet transfusion, low-molecular-weight heparin and Imipenem/Cilastatin (IPM/CS) under the tentative diagnosis of sepsis. Gram-negative thin rod-shaped bacteria were observed in the initial blood cultures after 48 hours, which was identified as Capnocytophaga canimorsus by mass spectrometry, PCR and sequence analysis of 16S rRNA gene and gyrB gene. IPM/CS was continued for 14 days. Physical symptoms such as fever, rash and multiple arthritis improved within 10 days. The platelets, CRP, and AST/ALT returned to near normal levels after 12 days. CT, MRI and ultrasound examinations of the painful joints revealed a small amount of fluid in the knee joints, but were otherwise non-specific. We report herein on a case of C. canimorsus sepsis which presented with polyarthritis of the major joints and a multiple pinkish macro-rash, treated adequately with IPM/CS. Early diagnosis and immediate broad-spectrum antibiotics could be the keys to the treatment of severe C. canimorsus infection.

We present 2 cases of disseminated Streptococcus agalactiae bacteremia. The first case was a 62-year-old man who suffered from S. agalactiae bacteremia with vertebral osteomyelitis and discitis with paravertebral infection, multiple arthritis, meningitis and a brain abscess. He was treated with long-term antimicrobial therapy. The second case was a 69-year-old man who suffered from S. agalactiae bacteremia with vertebral osteomyelitis and discitis with paravertebral infection, endophthalmitis and a psoas abscess. He was treated with drainage and long-term antimicrobial therapy. Although neither case was diagnosed as having definite infective endocarditis, they were complicated with multiple metastatic abscesses. S. agalactiae is not a typical causative organism of infective endocarditis. However it can complicate disseminated infection in a similar manner as infective endocarditis.

A 56-year-old woman with a history of bronchiectasis presented with fever and a wet cough in August 2015. Chest radiography and CT scans carried out by her local doctor showed bronchiectasis and bronchial wall thickening with an infiltration shadow in the lingular lobe and left S⁶. No pathogenic bacteria were detected from a sputum culture, a bronchoscopy was performed and Exophiala dermatitidis was cultured from the bronchoalveolar lavage fluid.
She was diagnosed as having pulmonary phaeohyphomycosis caused by E. dermatitidis. Itoraconazole 150mg/day in capsule form was started in December 2015. Before confirming any amelioration, she was referred to our hospital in April 2016. We switched the treatment to itraconazole oral solution 200mg/day and it improved her symptoms and laboratory findings. We reported herein on this rare case of pulmonary phaeohyphomycosis caused by E. dermatitidis and effectively treated with itraconazole oral solution.

2016年4月16日に本震を認めた熊本地震発生後，熊本県北東部の避難所で急性胃腸炎症状を主訴とする被災者が多く受診し，一部はノロウィルスによる感染性胃腸炎と診断とされた．我々の行った感染対策及び時間経過について報告する．対象と期間：本震発生のあった4月16日から5月15日までの全患者数及び急性胃腸炎症状の患者数を，赤十字救護班と徳洲会救護チーム（特定非営利活動法人TMAT）の災害カルテから集計した．避難者数は自治体発表のものを参照した．経過：4 月21 日に集中豪雨があり，同日より下痢を中心とする急性胃腸炎症状を訴える患者の受診が急増し，うち1 例が後方搬送先でノロウィルスキット陽性となった．さらに翌22 日には12 例が同症状で受診したため，感染拡大防止対策，環境調整を行った．その内容は土足厳禁化の徹底，居住空間の清掃，次亜塩素酸によるトイレの清掃，手指衛生の徹底，急性胃腸炎症状有症状者の別室保護である．その結果4月24日から25日にかけて，感染性胃腸炎による受診者数が減少していった．集計によれば期間中の感染性胃腸炎症状による受診者数は64 例，ノロウィルスキットを用いた検査は確認されているものでは11 例で施行され，陽性は2 例であった．1 日平均の避難者1,000 例当たりの感染性胃腸炎受診者は5.8 例であった．結論：避難所における感染性胃腸炎の発生に対し，早期より感染拡大防止対策を行い，早期終息に寄与する事ができた．早期からの介入とともに，避難所設営時から医療・保健及び行政関係者らの感染対策を意識した準備と対応が重要と考えられた．