Additional varicella vaccination was carried out targeting 16 subjects who had immune adherence hemagglutination (IAHA) seroconversion following the initial varicella vaccination and did not contract breakthrough varicella after the initial vaccination. The median ages at the initial and additional vaccination were 2.1 (1.1-6.9) years old and 6.1 (4.4-10.5) years old, respectively. The mean interval between the initial and additional vaccination was 4.0 (3.2-5.2) years. IAHA and glycoprotein-based enzyme-linked immunosorbent assay (gpELISA) antibody titers were measured just before and 4-6 weeks after the additional vaccination. Side reaction was surveyed at four weeks after the additional vaccination, and compared with the results at the initial vaccination. IAHA and gpELISA seroconversion rates at the initial vaccination were 100％ and 88％ respectively. Prior to the additional vaccination, IAHA antibody titers significantly decreased in 50％ of the subjects, and became negative in 38％ of the subjects. On the other hand, a significant increase in IAHA antibody titers was observed in 25％ of the subjects, and this is assumed to be the result of a subclinical infection after the initial vaccination. The positive rate of both antibodies after the additional vaccination was 100％, the mean IAHA antibody titer (Log2) after the initial/additional vaccination in seropositive subjects was 4.6/6.5, and the mean gpELISA antibody titer (Log10) was 2.3/4.0. The mean IAHA and gpELISA antibody titers were higher after the additional vaccination than after the initial vaccination (p＜0.01, p＜0.01). This is considered to be the booster effect due to the additional vaccination. At 0-2 days after the additional vaccination, a rash at the injection site was observed in 56％ of the subjects, higher than the incidence after the initial vaccination (13％) (p＜0.05), but no severe systemic side reactions were observed at either the initial or the additional vaccination. In conclusion, an additional varicella vaccination 3-5 years after the initial vaccination is thought to have greater immunogenicity and is considered effective.

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The performance of a new version of the HIV p24 antigen and antibody combination assays (Genscreen Ultra HIV Ag-Ab) was evaluated by comparing it with three other fourth-generation enzyme immunoassays (Architect HIV Ag/Ab Combo assay, VIDAS HIV DUO Quick and Genscreen Plus HIV Ag-Ab). The assays were examined with 200 HIV positive samples, 1,000 HIV negative samples, 30 samples (28 positives including 24 samples of subtype A, B, Bʼ, C, D, F, G, B/D, CRF01_AE in HIV-1 group M, one sample of HIV-1 group O, three samples of HIV-2 and two negatives) of one worldwide HIV performance panel, 59 samples of ten HIV-1 seroconversion panels and the WHO international standard HIV-1 p24 antigen. Both the sensitivity and specificity of Genscreen Ultra HIV Ag-Ab were 100％. All of the 28 positive samples in the worldwide HIV performance panel were positive. The days of the earliest detection in the ten seroconversion panels were the same in three assays (Genscreen Ultra HIV Ag-Ab, Architect HIV Ag/Ab combo assay and VIDAS HIV DUO Quick). Genscreen Plus HIV Ag-Ab which is a former version of the Genscreen Ultra HIV Ag-Ab detected the earliest positive sample one bleed slower than the other three assays in 5 of 10 seroconversion panels. The p24 antigen limit of detection was determined in two ways, using the WHO international standard and three samples from HIV-1 antigen panels; the values obtained were 1IU/mL and 3.5-9.9pg/mL for Genscreen Ultra HIV Ag-Ab, 1IU/mL and 7.1-9.9pg/mL for Architect HIV Ag/Ab combo assay,0.5IU/mL and 4.0-7.1pg/mL for VIDAS HIV DUO Quick, and 32.0-56.5pg/mL for Genscreen Plus HIV Ag-Ab. In this study, we have shown that Genscreen Ultra HIV Ag-Ab has the sensitivity, specificity and p24 antigen limit of detection that is equal to those of two typical fourth-generation assays. This assay can be considered useful and reliable for HIV screening.

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Mycobacteria consist of 2 large groups: one is the tuberculosis complex, and the other is nontuberculous mycobacterium (NTM). Most of the NTM are generally non-virulent bacteria, but some NTMs have pathogenicity to humans. There are many reports of nosocomial infection cases caused by common bacteria such as multidrug-resistant Pseudomonas aeruginosa. Also, some cases of in-hospital infection due to NTM were reported. Unlike common bacteria, detection of mycobacteria is affected by various factors, such as stainability, time for colony forming, temperature and nutrition Mycobacterium chelonae chemovar niacinogenes was isolated from 5 patients in 73 nosocomial infection cases (60 patients and 13 suspected cases) at a certain hospital during the period from March 2007 until January 2009. One of the reasons for the expansion of infection and difficulty in identification of the bacteria was the properties of this mycobacterium. This bacterium was very faintly stained with Gram-staining. Therefore, this mycobacterium could only be detected at a hospital when Ziehl-Neelsen stain and the cultivation at 28℃ for more than 5 days were performed. MICs for Cefmenoxime and Tosufloxacin of the isolates were more than 128μg/mL. The isolates and type strasin of M. chelonae chemovar niacinogenes were also resistant to other drugs.

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The early diagnosis of human immunodeficiency virus (HIV) infection is important to provide effective antiviral treatment and to prevent transmission of HIV. One of the key issues to achieve this goal is to shorten the so-called “diagnostic window period” when the humoral immune response toward the virus is not fully developed during the acute phase of HIV-1 infection. In 2008, the Espline HIV Ag/Ab test kit (E4G, Fujirebio Inc. Japan) was marketed in Japan belonging to the fourth generation of HIV test kits characterized by its ability to detect both viral antigens (Ag) and anti-HIV-1/2 antibodies (Ab). E4G is the first and only fourth generation immunochromatographic HIV test kit approved in Japan at present. To evaluate its performance to diagnose acute HIV infection (AHI), E4G was compared with fourth generation Ag/Ab ELISA test kits, a third generation PA test kit, WB and real-time PCR for the testing of 25 AHI clinical specimens. E4G detected HIV infection in 18/25 specimens (sensitivity : 72.0％), of which the viral Ag was detected in only 2 specimens (8.0％) bearing a viral load＞10 million copies/mL. No spesimens were simultaneously reactive to both Ag and Ab against HIV. The third generation PA achieved a positive score of 17/25 specimens (68.0％), which was almost the same as the E4G figure. In contrast the fourth generation Ag/Ab ELISA scored all the 25 AHI specimens positive (sensitivity : 100％). Overall, although having the merit of offering a rapid diagnostic test for HIV infection, E4G does not provide a sensitivity in AHI diagnosis superior to test kits currently available.

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[Purpose] Atovaquone is effective and well-tolerated for the treatment of mild or moderate Pneumocystis pneumonia (PCP) and the prevention of PCP. When atovaquone was not yet approved in Japan, it was supplied by the Clinical Study Group for AIDS Drugs, which has been supported by the Japan Health Science Foundation since 1997. We investigated the status of use and the reported side effects, since atovaquone has recently been approved and made available in Japan. [Method] We retrospectively examined the application and adverse events associated with atovaquone use between January 1997 and March 2012. [Results] During this period, there were 721 new applications, increasing over time, with the highest rate of increase observed in recent years. Fifty-seven adverse events in 39 patients were reported. Drug eruption was the most common side effect (20 cases), followed by cytopenia (11 cases), fever (10 cases), and liver dysfunction (8 cases). Two deaths were reported (one with an unknown correlation, another with no comments provided). One case of liver dysfunction attributable to atovaquone was severe. In this case, the AST and ALT levels increased to 1,921IU/L, and 1,062IU/L, respectively on day 4 of atovaquone administration, but these levels improved after atovaquone discontinuation. No other severe side effects were reported. [Discussion] This study revealed that as in other countries, few side effects caused by atovaquone were reported in Japan. Moreover, there were no side effects unique to the Japanese population. However, caution is required when administering atovaquone, because a low incidence of severe atovaquone-induced liver dysfunction has been reported.

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We present herein a case report of a 59-year-old patient with HIV-1 infection who developed a CMV-induced pseudotumor of the duodenum. The patient presented with oral pain and dysphagia. Physical examination revealed oral thrush. An EIA and a Western blot assay for antibodies to HIV were positive. His CD4-positive lymphocyte count was initially 49/μL with an HIV viral load of 2.6×10⁵ copies/mL. Cytomegalovirus (CMV) reactivation was detected with the CMV antigenemia assay. He had CMV retinitis in both eyes with unilateral blurring. An endoscopic study revealed candida esophagitis, and a tumor-like lesion with an irregular ulcer at the papilla of Vater. Histological and immunohistochemical studies revealed a CMV-induced pseudotumor and severely inflamed duodenal mucosa with infiltration of CMV-positive cells. The patient was treated with oral valganciclovir and fluconazole for three weeks. As the oral thrush and retinitis showed improvement, he began antiretroviral therapy (ART), consisting of raltegravir and TDF/FTC. One month later the patientʼs CD4-positive cells increased to 130/μL and the level of HIV-RNA decreased to 160 copies/mL. The CMV retinitis had transiently worsened because of an ART-induced inflammatory response, immune reconstitution inflammatory syndrome (IRIS). Six months after the ART initiation, an endoscopic study revealed that the esophagitis and the lesion at the papilla had improved. Biopsy showed no CMV-positive cells in the epithelium. The patient was now in a relatively healthy condition. CMV-induced pseudotumors of the duodenum are rare, and sometimes resemble malignancy. However, because this tomor responds to medical treatment physicians treating severely immunocompromised patients should be aware of its presentation and treatment.

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We report herein on a case of Plasmodium malariae malaria with more than a 4-month incubation period. A 35-year-old Japanese man who first presented to our clinic with fever and history of travel to Papua New Guinea was suspected of having Plasmodium vivax malaria based on peripheral smear results. We admitted him and initiated treatment with mefloquine. After two days of therapy, he became afebrile. We discharged him, and P. vivax was later confirmed with PCR. We started mefloquine prophylaxis for a planned trip to Papua New Guinea. After his return, a standard dose of primaquine (15mg×14 days) was prescribed for a radical cure of P. vivax. About 4 months after his last visit to Papua New Guinea, he returned to our clinic with fever. We suspected a relapse of P. vivax malaria and admitted him for a second time. After two days of mefloquine therapy, his symptoms improved. We discharged him and restarted a higher dose of primaquine (30mg×14 days) therapy for a radical cure of P. vivax. Subsequently, the PCR test revealed the parasite was P. malariae and not P. vivax. Only 13 cases of Plasmodium malariae malaria have been reported in Japan during the past 10 years. Blood-stage schizonticides such as mefloquine is not active against the liver stage. Therefore, the use of these drugs for prophylaxis will not be effective for prevention of malaria if its liver stage is longer than the duration of effective chemoprophylaxis. Although the incubation period of P. malariae is typically 13 to 28 days, it occasionally lasts for months or even years. Careful attention should be given to the possibility that P.malariae occasionally has a long incubation period even in the absence of the hypnozoite stage.

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A 35-year-old male patient had a fever, cough, and other symptoms since the end of December 2010. The patient then developed a high fever and decreased S_PO₂, suggesting possible pneumonia. The patient was admitted to our hospital on the 6th day of illness. Chest computed tomography revealed multiple infiltrative shadows and ground-glass opacities distributed in a patchy pattern in the bilateral lungs. An atypical pneumonia was suspected, and we initiated antibiotic treatment with minocycline. However, the patient developed consciousness disturbance in the afternoon of the 7th day of illness. The high fever persisted, suggesting the patientʼs poor response to minocycline treatment, which was then replaced with ciprofloxacin and imipenem/cilastatin on the 8th day of illness. Streptococcuspneumoniae was detected in the blood culture bottles submitted at the time of admission. A head magnetic resonance imaging performed on that day showed a high intensity area in the splenium of the corpus callosum, leading to a diagnosis of encephalopathy. Methylprednisolone pulse therapy and gamma globulin treatment were initiated. The patient then recovered consciousness gradually with improvement of inflammatory responses and imaging findings. Subsequently, an influenza virus (H1N1) antibody level was found to have increased from less than 10 times to 640 times. Thus, it was determined that the patientʼs pneumonia and encephalopathy were attributable to the influenza A (H1N1) pdm09 virus during the flu season and Streptcoccal infection. Combination therapy, such as steroid pulse treatment, appropriate antibiotics and gamma globulin preparation was effective for both the flu-induced mixed pneumonia and encephalopathy in this patient.

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