Importance of HBsAg recognition by HLA molecules as revealed by responsiveness to different hepatitis B vaccines.

Hepatitis B (HB) vaccines (Heptavax-II and Bimmugen) designed based on HBV genotypes A and C are mainly used for vaccination against HB in Japan. To determine whether there are differences in the genetic background associated with vaccine responsiveness, genome-wide association studies were performed on 555 Heptavax-II and 1193 Bimmugen recipients. Further HLA imputation and detailed analysis of the association with HLA genes showed that two haplotypes, DRB1*13:02-DQB1*06:04 and DRB1*04:05-DQB1*04:01, were significantly associated in comparison with high-responders (HBsAb > 100 mIU/mL) for the two HB vaccines. In particular, HLA-DRB1*13:02-DQB1*06:04 haplotype is of great interest in the sense that it could only be detected by direct analysis of the high-responders in vaccination with Heptavax-II or Bimmugen. Compared with healthy controls, DRB1*13:02-DQB1*06:04 was significantly less frequent in high-responders when vaccinated with Heptavax-II, indicating that high antibody titers were less likely to be obtained with Heptavax-II. As Bimmugen and Heptavax-II tended to have high and low vaccine responses to DRB1*13:02, 15 residues were found in the Heptavax-II-derived antigenic peptide predicted to have the most unstable HLA-peptide binding. Further functional analysis of selected hepatitis B patients with HLA haplotypes identified in this study is expected to lead to an understanding of the mechanisms underlying liver disease.

Incidence and Risk Factors for Incident Syphilis among HIV-1-Infected Men Who Have Sex with Men in a Large Urban HIV Clinic in Tokyo, 2008-2015.

BACKGROUND: The epidemiology of incident syphilis infection among HIV-1-infected men who have sex with men (MSM) largely remains unknown. METHODS: The incidence and risk factors for incident syphilis (positive TPHA and RPR> = 1:8) among HIV-1-infected MSM who visited a large HIV clinic in Tokyo for the first time between 2008 and 2013 were determined, using clinical data and stored blood samples taken every three months for screening and determination of the date of incident syphilis. Poisson regression compared the incidence of syphilis at different observation periods. RESULTS: Of 885 HIV-1-infected MSM with baseline data, 34% either presented with active syphilis at baseline (21%) or became infected with syphilis during follow-up (13%). After excluding 214 patients (MSM with syphilis at baseline (n = 190) and no follow-up syphilis test (n = 24)), of 671 men, 112 (17%) developed incident syphilis with an incidence of 43.7/1,000 person-years [95% CI, 36.5-52.3]. The incidence decreased slightly during observation period although the trend was not significant (2008-2009: 48.2/1,000 person-years, 2010-2011: 51.1/1,000 person-years, 2012-2013: 42.6/1,000 person-years, 2014 to 2015: 37.9/1,000 person-years, p = 0.315). Multivariable analysis identified young age (<33 years versus >40, HR 4.0, 95%CI 2.22-7.18, p<0.001), history of syphilis at baseline (HR 3.0, 95%CI 2.03-4.47, p<0.001), positive anti-amoeba antibody (HR 1.8, 95%CI 1.17-2.68, p = 0.006), and high baseline CD4 count (CD4 ≥350 /µL versus CD4 <200, HR 1.6, 95%CI 1.00-2.53, p = 0.050) as risk factors for incident syphilis. Incidence of syphilis was particularly high among young patients (age <33 years: 60.1/1,000 person-years). Interestingly, 37% of patients with incident syphilis were asymptomatic. CONCLUSIONS: Although incidence of syphilis did not increase during the observation period, it was high among HIV-1-infected MSM, especially among young HIV-1-infected MSM and those with history of syphilis, in Tokyo. Regular screening for syphilis needs to be strictly applied to this population.

Long-Term Trends in Esophageal Candidiasis Prevalence and Associated Risk Factors with or without HIV Infection: Lessons from an Endoscopic Study of 80,219 Patients.

BACKGROUND: The prevalence of candida esophagitis (CE) might be changing in an era of highly active antiretroviral therapy (HAART) among HIV-infected patients or today's rapidly aging society among non-HIV-infected patients. However, few studies have investigated long-term CE trends, and CE risk factors have not been studied in a large sample, case-control study. This study aimed to determine long-term trends in CE prevalence and associated risk factors for patients with or without HIV infection. METHODS: Trends in CE prevalence were explored in a cohort of 80,219 patients who underwent endoscopy between 2002 and 2014. Risks for CE were examined among a subcohort of 6,011 patients. In risk analysis, we assessed lifestyles, infections, co-morbidities, immunosuppressants, and proton-pump inhibitors (PPIs). All patients were tested for HIV, hepatitis B or C virus, and syphilis infection. For HIV-infected patients, sexual behavior, CD4 cell count, history of HAART were also assessed. RESULTS: CE prevalence was 1.7% (1,375/80,219) in all patients, 9.8% (156/1,595) in HIV-infected patients, and 1.6% (1,219/78,624) in non-HIV-infected patients. CE prevalence from 2002-2003 to 2012-2014 tended to increase in non-HIV-infected patients (0.6% to 2.5%; P<0.01) and decrease in HIV-infected patients (13.6% to 9.0%; P=0.097). Multivariate analysis revealed increasing age (odds ratio [OR], 1.02; p=0.007), HIV infection (OR, 4.92; p<0.001), and corticosteroid use (OR, 5.90; p<0.001) were significantly associated with CE, and smoking (OR, 1.32; p=0.085) and acetaminophen use (OR, 1.70; p=0.097) were marginally associated. No significant association was found with alcohol consumption, hepatitis B or C virus, syphilis, diabetes mellitus, cardiovascular disease, cerebrovascular disease, chronic kidney disease, liver cirrhosis, anticancer, or PPIs use. In HIV-infected patients, CD4 cell count <100/µL (OR, 4.83; p<0.001) and prior HAART (OR, 0.35; p=0.006) were independently associated with CE, but sexual behavior was not. Among corticosteroid users, CE was significantly associated with higher prednisone-equivalent dose (p=0.043 for trend test). CONCLUSIONS: This large, endoscopy-based study demonstrated that CE prevalence increased in non-HIV-infected patients but decreased in HIV-infected patients over 13 years. Risk analysis revealed that increasing age, HIV infection, and corticosteroids use, particularly at higher doses, were independently associated with CE, but alcohol, other infections, diabetes, anticancer drugs, and PPIs use were not.

HIV-1 infection, but not syphilis or HBV infection, is a strong risk factor for anorectal condyloma in Asian population: a prospective colonoscopy screening study.

OBJECTIVE: To investigate the association between anorectal precancerous lesions, including condyloma, and sexually transmitted infections (STI) in Asian population. METHODS: This prospective study enrolled 2677 patients who underwent high-resolution colonoscopy for anorectal cancer screening. Anorectal lesions were diagnosed based on endoscopic findings and confirmed by biopsy. The association of HIV-1 infection, syphilis, and HBV infection with anorectal lesion was estimated by multivariate logistic regression. In HIV-1-infected patients (n=244), anal canal HPV-DNA was screened and genotyped. RESULTS: Although no malignancy was identified, anorectal condyloma was diagnosed in 32 (1.2%) male patients. 41% of anorectal condyloma cases had no specific lower GI symptoms. Multivariate analysis identified HIV-1 infection, but not syphilis or HBV infection, as an independent significant factor for condyloma (OR: 176.5, 95%CI 22.52-1383, p<0.001). In HIV-1 infected patients, positive type 16/18 HPV-DNA (OR: 4.766, 95%CI 1.838-12.36, p=0.001), lower CD4 cell count (per 100/µl decrement, OR: 1.056, 95%CI 1.056-1.587, p=0.013), and current smoking (OR: 3.828, 95%CI 1.486-9.857, p=0.005) were independently associated with anorectal condyloma. CONCLUSIONS: HIV-1 infection, but not syphilis or HBV infection, was identified as a strong risk for anorectal condyloma. Anal HPV 16/18 was highly prevalent in patients with HIV-1 infection, especially in those with condyloma.

Long-term exposure to tenofovir continuously decrease renal function in HIV-1-infected patients with low body weight: results from 10 years of follow-up.

OBJECTIVES: To investigate the effect of long-term tenofovir disoproxil fumarate (TDF) use on renal function, especially in patients with low body weight who are vulnerable to TDF nephrotoxicity. DESIGN: A single-center, observational study in Tokyo, Japan. METHODS: We performed a 10 years cohort study of 792 HIV-1-infected patients. The effect of long-term TDF use on estimated glomerular filtration rate (eGFR) was investigated on treatment-naive patients who started TDF-containing antiretroviral therapy (n = 422) and those who started abacavir-containing antiretroviral therapy as control (n = 370). Three renal endpoints were examined by the logistic regression model: decrement in eGFR of higher than 10 ml/min per 1.73 m relative to the baseline, more than 25% decrement in eGFR, and eGFR lower than 60 ml/min per 1.73 m at least 3 months apart. The loss in eGFR was estimated using linear mixed models for repeated measures. RESULTS: The median weight at baseline was 63 kg. TDF use increased the risk of all three renal outcomes compared with the control group: higher than 10 ml/min per 1.73 m decrement in eGFR [adjusted odds ratio (OR) = 2.1, 95% confidence interval (CI) 1.45-3.14, P < 0.001], more than 25% decrement (adjusted OR = 2.1, 95% CI 1.50-2.90, P < 0.001), and eGFR lower than 60 ml/min per 1.73 m at least 3 months apart (adjusted OR = 3.9, 95% CI 1.62-9.36, P = 0.002). The cumulative mean loss relative to the control after 1, 2, 3, 4, and 5 years of TDF exposure was -3.8, -3.6, -5.5, -6.6, and -10.3 ml/min per 1.73 m, respectively, indicating that the loss in eGFR increased over time (P < 0.001). CONCLUSION: In this cohort of patients with low body weight, TDF exposure increased the risk of renal dysfunction. Furthermore, the loss in eGFR relative to the control increased continuously up to 5 years.

Single-nucleotide polymorphisms in the UDP-glucuronosyltransferase 1A-3' untranslated region are associated with atazanavir-induced nephrolithiasis in patients with HIV-1 infection: a pharmacogenetic study.

OBJECTIVES: Ritonavir-boosted atazanavir (atazanavir/ritonavir) is a widely used antiretroviral drug, though it can potentially cause nephrolithiasis. The aim of this study was to determine the relationship between polymorphisms in genes encoding proteins involved in metabolism and transportation of atazanavir, and atazanavir/ritonavir-induced nephrolithiasis in HIV-1-infected patients treated with atazanavir/ritonavir. METHODS: Nineteen SNPs in the ABCB1, NR1I2, UGT1A1, SLCO1B1 and CYP3A5 genes were examined in case patients with atazanavir/ritonavir-induced nephrolithiasis (n = 31) and controls (n = 47). Case patients were those with a clinical diagnosis of nephrolithiasis while on atazanavir/ritonavir, based on new-onset acute flank pain plus one of the following: (i) new-onset haematuria; (ii) documented presence of stones by either abdominal ultrasonography or CT; or (iii) confirmed stone passage. Control patients were consecutively enrolled among those with >2 years of atazanavir/ritonavir exposure free of nephrolithiasis. Genotyping was performed by allelic discrimination using TaqMan 5'-nuclease assays with standard protocols. Associations between alleles and atazanavir/ritonavir-induced nephrolithiasis were tested by univariate and multivariate logistic regression analyses. RESULTS: Multivariate analysis showed a significant association between atazanavir/ritonavir-induced nephrolithiasis and genotype T/C versus C/C at position c.211 (adjusted OR = 3.7; 95% CI, 1.13-11.9; P = 0.030), genotype G/C versus C/C at 339 (adjusted OR = 5.8; 95% CI, 1.56-21.3; P = 0.009) and genotype G/G or G/C versus C/C at 440 (adjusted OR = 5.8; 95% CI, 1.56-21.3; P = 0.009) of the UGT1A-3' untranslated region (UTR). CONCLUSIONS: This is the first known study to identify the association between SNPs in the UGT1A-3'-UTR and atazanavir-induced nephrolithiasis. Further studies are warranted to confirm this association and to elucidate how these SNPs might influence atazanavir exposure.

Evaluation of an automated rapid diagnostic assay for detection of Gram-negative bacteria and their drug-resistance genes in positive blood cultures.

We evaluated the performance of the Verigene Gram-Negative Blood Culture Nucleic Acid Test (BC-GN; Nanosphere, Northbrook, IL, USA), an automated multiplex assay for rapid identification of positive blood cultures caused by 9 Gram-negative bacteria (GNB) and for detection of 9 genes associated with ß-lactam resistance. The BC-GN assay can be performed directly from positive blood cultures with 5 minutes of hands-on and 2 hours of run time per sample. A total of 397 GNB positive blood cultures were analyzed using the BC-GN assay. Of the 397 samples, 295 were simulated samples prepared by inoculating GNB into blood culture bottles, and the remaining were clinical samples from 102 patients with positive blood cultures. Aliquots of the positive blood cultures were tested by the BC-GN assay. The results of bacterial identification between the BC-GN assay and standard laboratory methods were as follows: Acinetobacter spp. (39 isolates for the BC-GN assay/39 for the standard methods), Citrobacter spp. (7/7), Escherichia coli (87/87), Klebsiella oxytoca (13/13), and Proteus spp. (11/11); Enterobacter spp. (29/30); Klebsiella pneumoniae (62/72); Pseudomonas aeruginosa (124/125); and Serratia marcescens (18/21); respectively. From the 102 clinical samples, 104 bacterial species were identified with the BC-GN assay, whereas 110 were identified with the standard methods. The BC-GN assay also detected all ß-lactam resistance genes tested (233 genes), including 54 bla(CTX-M), 119 bla(IMP), 8 bla(KPC), 16 bla(NDM), 24 bla(OXA-23), 1 bla(OXA-24/40), 1 bla(OXA-48), 4 bla(OXA-58), and 6 blaVIM. The data shows that the BC-GN assay provides rapid detection of GNB and ß-lactam resistance genes in positive blood cultures and has the potential to contributing to optimal patient management by earlier detection of major antimicrobial resistance genes.

Long-term use of protease inhibitors is associated with bone mineral density loss.

HIV-infected patients are at high risk for bone mineral density (BMD) loss. The present study was designed to provide information on characteristics of BMD abnormalities in Japanese HIV-1-infected patients and risk factors involved in worsening of BMD. A total of 184 Japanese HIV-1-infected men were studied with a dual-energy X-ray absorptiometry scan (DXA) at the lumbar spine and femoral neck. Multivariate logistic regression models were used for comparison of the impact of risk factors on BMD loss. Osteopenia and osteoporosis were diagnosed in 46% and 10% of the patients at lumbar spine, and 54% and 12% at femoral neck, respectively. In logistic analysis, factors associated with low BMD at both lumbar spine and femoral neck were long-term treatment with a protease inhibitor (PI) [odds ratio (OR) 1.100 and 1.187 per 1 year increase of PI use; 95% confidence interval (CI) 1.003-1.207 and 1.043-1.351; p=0.042 and 0.009, respectively] and a low body mass index [OR: 0.938 and 0.852, CI 0.892-0.992 and 0.783-0.927; p=0.024 and <0.001, respectively]. Patients who discontinued PI had a significantly higher BMD than those who currently use PI at lumbar spine (t score -0.8 vs. -1.3, p=0.04) but not at femoral neck (-1.3 vs. -1.5, p=0.38). In HIV-infected Japanese patients, the duration of treatment with PI correlated significantly with BMD loss. Discontinuation of PI is a promising option in the treatment of BMD loss since it allows recovery of BMD, especially in the lumbar spine.

Skin rash induced by ritonavir-boosted darunavir is common, but generally tolerable in an observational setting.

Ritonavir-boosted darunavir (DRV/r) is a protease inhibitor widely used in the treatment of HIV-1 infection. However, skin rash is a well-known adverse event of DRV, and limited data are available from observational settings. This observational study examined the characteristics of DRV-induced skin rash in treatment-naïve patients who commenced once-daily DRV/r-containing antiretroviral therapy (ART). Of the 292 study patients, DRV rashes developed in 31 (11%) patients with a median latency of 10 days (developing from 7 to 14 days in 93%) from initiation of ART. DRV skin rash was generally mild, as only one patient (3%) had grade 3 rash whereas 24 (77%) patients had grade 2 and 6 (19%) patients had grade 1. Only two patients (7%) discontinued DRV/r due to skin rash, and the other continued DRV/r and their rashes disappeared completely without any complications. Interestingly, DRV rash occurred more frequently to patients with less advanced HIV-1 infection than those with advanced infection. The incidence of DRV rash was not significantly different between patients with and without history of sulfonamide allergy (p = 0.201). Furthermore, when we exclude patients without history of sulfonamide use and only examine patients with sulfonamide use (n = 145), the result was similar (p = 0.548). In conclusion, DRV rashes were frequently observed but the prognosis was benign. Most patients tolerated DRV rashes with use of oral steroid or antihistamine without discontinuation of DRV. To date, there is no clear clinical evidence to suggest that DRV should be avoided in patients with history of sulfonamide allergy.

Pharmacokinetics of rifabutin in Japanese HIV-infected patients with or without antiretroviral therapy.

OBJECTIVE: Based on drug-drug interaction, dose reduction of rifabutin is recommended when co-administered with HIV protease inhibitors for human immunodeficiency virus (HIV)-associated mycobacterial infection. The aim of this study was to compare the pharmacokinetics of rifabutin administered at 300 mg/day alone to that at 150 mg every other day combined with lopinavir-ritonavir in Japanese patients with HIV/mycobacterium co-infection. METHODS: Plasma concentrations of rifabutin and its biologically active metabolite, 25-O-desacetyl rifabutin were measured in 16 cases with HIV-mycobacterial coinfection. Nine were treated with 300 mg/day rifabutin and 7 with 150 mg rifabutin every other day combined with lopinavir-ritonavir antiretroviral therapy (ART). Samples were collected at a median of 15 days (range, 5-63) of rifabutin use. RESULTS: The mean Cmax and AUC0-24 of rifabutin in patients on rifabutin 150 mg every other day were 36% and 26% lower than on 300 mg/day rifabutin, while the mean Cmax and AUC0-24 of 25-O-desacetyl rifabutin were 186% and 152% higher, respectively. The plasma concentrations of rifabutin plus its metabolite were similar between the groups within the first 24 hours, but it remained low during subsequent 24 to 48 hours under rifabutin 150 mg alternate day dosing. CONCLUSION: Rifabutin dose of 150 mg every other day combined with lopinavir-ritonavir seems to be associated with lower exposure to rifabutin and its metabolite compared with rifabutin 300 mg/day alone in Japanese patients. Further studies are needed to establish the optimal rifabutin dose during ART. The results highlight the importance of monitoring rifabutin plasma concentration during ART. TRIAL REGISTRATION: UMIN-CTR (https://upload.umin.ac.jp/cgi-open-bin/ctr/ctr.cgi?function=search&action=input&language=E) UMIN000001102.

Assessment of antigenemia assay for the diagnosis of cytomegalovirus gastrointestinal diseases in HIV-infected patients.

We conducted a single-center prospective study to evaluate the utility of cytomegalovirus (CMV) antigenemia assay for the diagnosis of CMV-gastrointestinal disease (GID). The study subjects were HIV-infected patients with CD4 count ≤200 µL/cells who had undergone endoscopy. A definite diagnosis of CMV-GID was made by histological examination of endoscopic biopsied specimen. CMV antigenemia assay (C10/C11 monoclonal antibodies), CD4 count, HIV viral load, history of HAART, and gastrointestinal symptoms as measured by 7-point Likert scale, were assessed on the same day of endoscopy. One hundred cases were selected for analysis, which were derived from 110 cases assessed as at high-risk for CMV-GID after endoscopy screening of 423 patients. Twelve patients were diagnosed with CMV-GID. Among the gastrointestinal symptoms, mean bloody stool score was significantly higher in patients with CMV-GID than in those without (2.5 vs. 1.7, p=0.02). The area under the receiver-operating characteristic curve of antigenemia was 0.80 (95%CI 0.64-0.96). The sensitivity, specificity, positive likelihood ratio (LR), and negative LR of antigenemia were 75.0%, 79.5%, 3.7, and 0.31, respectively, when the cutoff value for antigenemia was ≥1 positive cell per 300,000 granulocytes, and 50%, 92.0%, 5.5, and 0.55, respectively, for ≥5 positive cells per 300,000 granulocytes. In conclusion, CMV antigenemia seems a useful diagnostic test for CMV-GID in patients with HIV infection. The use of ≥5 positive cells per 300,000 granulocytes as a cutoff value was associated with high specificity and high positive LR. Thus, a positive antigenemia assay with positive endoscopic findings should allow the diagnosis of CMV-GID without biopsy.

Diagnostic value of endothelial markers and HHV-8 staining in gastrointestinal Kaposi sarcoma and its difference in endoscopic tumor staging.

AIM: To clarify the diagnostic values of hematoxylin and eosin (HE), D2-40, CD31, CD34, and HHV-8 immunohistochemical (IHC) staining in gastrointestinal Kaposi's sarcoma (GI-KS) in relation to endoscopic tumor staging. METHODS: Biopsy samples (n = 133) from 41 human immunodeficiency virus-infected patients were reviewed. GI-KS was defined as histologically negative for other GI diseases and as a positive clinical response to KS therapy. The receiver operating characteristic area under the curve (ROC-AUC) was compared in relation to lesion size, GI location, and macroscopic appearances on endoscopy. RESULTS: GI-KS was confirmed in 84 lesions (81.6%). Other endoscopic findings were polyps (n = 9), inflammation (n = 4), malignant lymphoma (n = 4), and condyloma (n = 2), which mimicked GI-KS on endoscopy. ROC-AUC of HE, D2-40, blood vessel markers, and HHV-8 showed results of 0.83, 0.89, 0.80, and 0.82, respectively. For IHC staining, the ROC-AUC of D2-40 was significantly higher (P < 0.05) than that of HE staining only. In the analysis of endoscopic appearance, the ROC-AUC of HE and IHC showed a tendency toward an increase in tumor staging (e.g., small to large, patches, and polypoid to SMT appearance). D2-40 was significantly (P < 0.05) advantageous in the upper GI tract and for polypoid appearance compared with HE staining. CONCLUSION: The diagnostic value of endothelial markers and HHV-8 staining was found to be high, and its accuracy tended to increase with endoscopic tumor staging. D2-40 will be useful for complementing HE staining in the diagnosis of GI-KS, especially in the upper GI tract and for polypoid appearance.

Factors associated with esophageal candidiasis and its endoscopic severity in the era of antiretroviral therapy.

BACKGROUND: Candidia esophagitis (CE) is an AIDS-defining condition, usually occurring in individuals with low CD4 counts of <200 cells/µL. Endoscopy is a valuable definitive diagnostic method for CE but may not be indicated for asymptomatic patients or for those with high CD4 counts or without oral candidiasis. This study assessed such patients to clarify the factors associated with CE and its severity on endoscopy in the highly active antiretroviral therapy (HAART) era. METHODOLOGY PRINCIPAL FINDINGS: A total of 733 HIV-infected patients who underwent upper gastrointestinal (GI) endoscopy were analyzed. Sexual behavior, CD4(+) count, HIV-RNA viral load (VL), history of HAART, GI symptoms, GI diseases, and oral candidiasis were assessed. Endoscopic severity of CE was classified as mild (Kodsi's grade I/II) or severe (grade III/IV). Of the 733 subjects, 62 (8.46%) were diagnosed with CE (mild, n = 33; severe, n = 29). Of them, 56.5% (35/62) had no GI symptoms, 30.6% (19/62) had CD4 + ≥200 cells/µL, and 55.3% (21/38) had no oral candidiasis. Univariate analysis found lower CD4+ counts, higher HIV VL, and no history of HAART to be significantly associated with CE. With lower CD4(+) counts and higher HIV VL, CE occurrence increased significantly (P<0.01 for trend in odds). Multivariate analysis showed low CD4+ counts and high HIV VL to be independently associated with CE. Of the severe CE patients, 55.2% (16/29) had no GI symptoms and 44.4% (8/18) had no oral candidiasis. Median CD4(+) counts in severe cases were significantly lower than in mild cases (27 vs. 80; P = 0.04). CONCLUSIONS: Low CD4+ counts and high HIV VL were found to be factors associated with CE, and advanced immunosuppression was associated with the development of severity. Endoscopy is useful as it can detect CE, even severe CE, in patients without GI symptoms, those with high CD4 counts, and those without oral candidiasis.

Combined endoscopy, aspiration, and biopsy analysis for identifying infectious colitis in patients with ileocecal ulcers.

BACKGROUND & AIMS: The ileocecal area is commonly involved in infection and inflammatory colonic diseases, but differential diagnosis can be difficult. We identified definitive endoscopic findings and a sample collection method for diagnosing infectious colitis. METHODS: In a retrospective study, we analyzed data on 128 patients with ileocecal ulcer who underwent colonoscopy from 2007-2011 at the National Center for Global Health and Medicine in Tokyo, Japan. We collected information on location, size, number, and distinctive endoscopic findings and estimated diagnostic odds ratios (ORs). The sensitivities of microscopy, culture, polymerase chain reaction, and histologic methods in identifying patients with infection were compared with those of standard stool, endoscopic aspirated intestinal fluid, or biopsy analyses. RESULTS: Of the 128 patients, 100 had infections, and 28 had Crohn's disease, Behçet's disease, or other inflammatory diseases. Predictive endoscopic findings were as follows: for amebiasis of the cecum (OR, 17.8), with exudates (OR, 13.9) and round-shaped ulcer (OR, 5.77); for tuberculosis (TB) with transverse-shaped ulcer (OR, 175), scar (OR, 34.6), linear-shaped ulcer (OR, 23.9), or ≥10 mm (OR, 14.0); for cytomegalovirus with round-shaped ulcer (OR, 4.09); and for Campylobacter with cecal valve lesion (OR, 58.3) or ≥10 mm (OR, 10.4). The sensitivity of endoscopic sample collection was significantly higher than that of standard stool sample collection for the diagnosis of amebiasis, TB, non-TB mycobacteria, and other bacteria (P < .05). The methods that detected infection with the highest levels of sensitivity were biopsy with histology for amebiasis, biopsy with culture for TB, biopsy with polymerase chain reaction for cytomegalovirus, and aspiration of intestinal fluid with culture for Campylobacter. CONCLUSIONS: Combining results from endoscopic analysis with appropriate sample collection and pathogen detection methods enables infectious colitis to be differentiated from other noninfectious colonic diseases.

False-Negative Results of Endoscopic Biopsy in the Diagnosis of Gastrointestinal Kaposi's Sarcoma in HIV-Infected Patients.

Kaposi's sarcoma (KS) is a rare endothelial neoplasm mainly involving the skin, but it is often associated with AIDS. Diagnosis of gastrointestinal (GI) tract KS, a common site of visceral involvement in AIDS, is important, but endoscopic biopsy carries a risk of false-negative results (FNRs) due to its submucosal appearance. This study sought to determine the rate and causes of FNR for endoscopic biopsy of GI-KS lesions. Endoscopic biopsy samples of 116 GI-KS lesions were reviewed retrospectively. All GI-KS lesions were confirmed to be resolved following KS therapy. FNRs were yielded for 41 of the lesions (35.3%). Among upper and lower GI sites, the esophagus was the only site significantly associated with FNRs (P < 0.01). Small size (<10 mm) and patches found on endoscopy were significantly associated with FNRs (P < 0.05). Findings of submucosal tumor (SMT) with ulceration were significantly associated with true-positive results (P < 0.05). In conclusion, FNRs were found in 35.3% of GI-KS lesions and were especially related to the site of the esophagus and endoscopic early stage (small size or patch appearance). An SMT with ulceration may be relatively easy to diagnose on endoscopic biopsy. Caution should be exercised when performing endoscopic biopsy of these lesions in AIDS patients and evaluating the histological features.

Predictive clinical factors in the diagnosis of gastrointestinal Kaposi's sarcoma and its endoscopic severity.

BACKGROUND: The diagnosis of gastrointestinal (GI) involvement in Kaposi's sarcoma (KS) is important to make because the need for treatment depends on the extent of the disease. Moreover, severe GI lesions can cause serious complications. Endoscopy with biopsy is an extremely useful method to diagnose GI-KS. However, determining the indications for endoscopy is difficult because KS can occur without GI symptoms or cutaneous KS. This study sought to clarify predictive clinical factors for GI-KS and its severity on endoscopy. METHODOLOGY/PRINCIPAL FINDINGS: A total of 1,027 HIV-infected patients who underwent endoscopy were analyzed. Sexual behavior, CD4 count, HIV RNA, history of highly active antiretroviral therapy (HAART), GI symptoms, and cutaneous KS were assessed. Endoscopic severity including bulky tumor, ulceration, and number of lesions were evaluated. Thirty-three patients had GI-KS and 46 patients cutaneous KS. Among the GI-KS patients, 78.8% (26/33) had no GI symptoms and 24.2% (8/33) had no cutaneous KS. Univariate analysis identified men who have sex with men (MSM), CD4 <100 cells/µL, HIV RNA ≥10,000 copies/mL, no history of HAART, and cutaneous KS were significantly associated with GI-KS. Among these factors, cutaneous KS was closely related to GI-KS on multivariable analysis. Among patients without cutaneous KS, MSM and CD4 count <100 cells/µL were the only independent clinical factors related to GI-KS. Bulky tumor was significantly associated with CD4 <100 cells/µL and large number of lesions was significantly associated with HIV-RNA ≥10,000 copies/mL. CONCLUSIONS: To diagnose GI-KS, clinical factors need to be considered before endoscopy. The presence of GI symptoms is not useful in predicting GI-KS. MSM and CD4 count <100 cells/µL are predictive factors among patients without cutaneous KS. Caution should be exercised especially in patients with low CD4 counts or high HIV viral loads as they are more likely to develop severe GI-KS lesions.

Drug-induced acute interstitial nephritis mimicking acute tubular necrosis after initiation of tenofovir-containing antiretroviral therapy in patient with HIV-1 infection.

We describe a case of 68-year-old Japanese man with HIV-1 infection who developed acute kidney injury with prominent tubular dysfunction immediately after starting tenofovir-containing antiretroviral therapy. Antiretroviral therapy was discontinued in two weeks but renal function, as well as tubular function, did not shown full recovery even at a 3-year follow-up examination. Acute tubular necrosis, a rare but well-known side effect of tenofovir, was suspected, but kidney biopsy confirmed interstitial nephritis. It is important to distinguish drug-induced interstitial nephritis from acute tubular necrosis, because early steroid administration can improve renal dysfunction caused by acute interstitial nephritis.

Outbreaks of Pneumocystis pneumonia in 2 renal transplant centers linked to a single strain of Pneumocystis: implications for transmission and virulence.

BACKGROUND: There have been numerous reports of clustered outbreaks of Pneumocystis pneumonia (PCP) at renal transplant centers over the past 2 decades. It has been unclear whether these outbreaks were linked epidemiologically to 1 or several unique strains, which could have implications for transmission patterns or strain virulence. METHODS: Restriction fragment length polymorphism (RFLP) analysis was used to compare Pneumocystis isolates from 3 outbreaks of PCP in renal transplant patients in Germany, Switzerland, and Japan, as well as nontransplant isolates from both human immunodeficiency virus (HIV)-infected and uninfected patients. RESULTS: Based on RFLP analysis, a single Pneumocystis strain caused pneumonia in transplant patients in Switzerland (7 patients) and Germany (14 patients). This strain was different from the strain that caused an outbreak in transplant patients in Japan, as well as strains causing sporadic cases of PCP in nontransplant patients with or without HIV infection. CONCLUSIONS: Two geographically distinct clusters of PCP in Europe were due to a single strain of Pneumocystis. This suggests either enhanced virulence of this strain in transplant patients or a common, but unidentified, source of transmission. Outbreaks of PCP can be better understood by enhanced knowledge of transmission patterns and strain variation.