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Clostridioides (Clostridium) difficile (C. difficile) infection is one of the most common causes of increased morbidity and mortality. Approximately 500 000 C. difficile infections (CDIs) occur each year in the United States, and they result in more than 29 000 deaths. Patients with haematologic diseases are at a higher risk for this infection due to frequent hospitalization and exposure to treatment-associated risk factors. Whilst several currently available antimicrobial agents offer resolution, recurrence of infection remains a major concern. Recent advancement in deciphering C. difficile virulence mechanisms and identification of its allies in contributing to the infection has led to the development of alternative treatment strategies. Here, we will provide a contemporary discussion of how major risk factors in haematologic diseases, such as immunosuppression, chemoradiation, use of antibiotic, proton pump inhibitor and opioid, and deficiency in butyrate and antimicrobial peptides contribute to C. difficile infection. Next, we will highlight different approaches to control and mitigate this infection such as antibiotic stewardship and faecal microbiota transplantation. Finally, we will explore several emerging treatments such as use of pre- and probiotics, immunotherapy and microbiome-sparing agents. 相似文献
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Yakoob J Jafri W Jafri N Khan R Islam M Beg MA Zaman V 《The American journal of tropical medicine and hygiene》2004,70(4):383-385
This study was designed to examine stool specimens of irritable bowel syndrome (IBS) patients for Blastocystis hominis, a common intestinal parasite. One hundred fifty patients were enrolled, 95 IBS cases and 55 controls. These patients provided a medical history, and underwent physical and laboratory evaluations that included stool microscopy and culture for B. hominis and colonoscopy. The 95 cases (51 males and 44 females) had a mean +/- SD age of 37.8 +/- 13.2 years. Stool microscopy was positive for B. hominis in 32% (30 of 95) of the cases and 7% (4 of 55) of the controls (P = 0.001). Stool culture was positive in 46% (44 of 95) of the cases and 7% (4 of 55) of the controls (P < 0.001). Stool culture for B. hominis in IBS was more sensitive than microscopy (P < 0.001). Blastocystis hominis was frequently demonstrated in the stool samples of IBS patients; however, its significance in IBS still needs to be investigated. Stool culture has a higher positive yield for B. hominis than stool microscopy. 相似文献
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Despite recent advances in pharmacologic therapy of heart failure, mortality remains high. There is growing evidence that thromboembolic events may contribute to these events. There is evidence for platelet activation, hypercoagulability and endothelial dysfunction in heart failure. The incidence of overt thromboembolism in heart failure is low. Ischemic events are a frequent prelude to heart failure. Thus, subclinical embolism and ischemic events may be contributing factors to the morbidity and mortality in heart failure patients. The role of antithrombotic therapy with warfarin or aspirin needs to be systematically investigated to determine if such therapy can reduce mortality in heart failure. Such information is particularly essential because non-randomized data have raised the possibility that aspirin may interfere with the beneficial effects of angiotensin converting enzyme inhibitors. This review summarizes available data on warfarin and aspirin therapy in heart failure. 相似文献
16.
Buckingham SC Jafri HS Bush AJ Carubelli CM Sheeran P Hardy RD Ottolini MG Ramilo O DeVincenzo JP 《The Journal of infectious diseases》2002,185(9):1222-1228
Forty-one previously healthy children <2 years of age who required mechanical ventilation for respiratory syncytial virus (RSV) infection were randomized to receive dexamethasone (0.5 mg/kg; n=22) or saline placebo (n=19) intravenously every 12 h for 4 days. RSV quantity was measured by quantitative plaque assay in fresh tracheal and nasal aspirates obtained at intervals of 24+/-3 h on days 0, 1, 2, 5, and 7 following entry. Analysis by linear mixed-effects modeling demonstrated a significantly greater decline in mean tracheal RSV quantity in the placebo group than in the dexamethasone group from day 0 to day 1 (0.82 vs. 0.21 log pfu/mL; P=.01) and from day 0 to day 2 (1.45 vs. 0.53 log pfu/mL; P=.03). No differences were found between groups in nasal RSV quantity, white blood cell counts in tracheal or nasal aspirates, serum neutralizing antibody titers during convalescence, or duration of mechanical ventilation, intensive care unit stay, or hospital stay. 相似文献
17.
AIM: To investigate the association between cytokine gene polymorphism and disease status in chronic hepatitis C genotype 3 by liver biopsy, ALT, HCV RNA levels and response to treatment. METHODS: Patients with chronic hepatitis C genotype 3 were analyzed for single nucleotide polymorphisms of interleukin (IL)-10, IL-1 beta, interferon-gamma (IFN-γ), tumor necrosis factor-alpha (TNF-α) and transforming growth factor-beta (TGF-β) by polymerase chain reaction using sequence-specific oligonucleotide primers. Liver biopsies were assessed by modified histological activity index (HAI) scoring system using a scale of 0-18 for grading the necro-inflammatory activity and 0-6 for staging the fibrosis. HCV RNA levels were determined by bDNA assay. The patients were treated with interferon alpha and ribavirin for 6 mo. Sustained virological response was assessed 6 mo after the completion of the treatment. RESULTS: Out of the 40 patients analyzed, 26 were males. Mean age was 40.5±12.5 years (range 18-65 years). The frequencies of different dimorphic polymorphisms based on single nucleotide substitution were as follows: IL-10-1082 G/A 85%, A/A 12.5%, G/ G 2.5%; IL-10-819 A/C 87.5%, C/C 10%, A/A 2.5%; IL-10-592 C/A 72.5%, C/C 27.5%; IL-1 C 90%, U 10%; IFN-874 T/A 50%, T/T 27.5%, A/A 22.5%; TNF-308 A/G 95%, GIG 5%; TGF-10 T/C 52.5%, C/C 35%, T/T 12.5%. The mean grades of necro-inflammatory activity of different genotypes of IL-10 at promoter site -1082 were A/A = 3.6, A/G = 5.0, and G/G = 10.0 and the difference was significant (P = 0.029). The difference in the stage of disease at a scale of 0-6 was A/A 0.8, A/G 2.3, and G/G 4.0 (P = 0.079). The difference in the HAI seemed to be related to the presence of allele -1082G. For IL-10 -819 genotypes, mean scores of fibrosis were A/A = 6.0, A/C = 2.2, and C/C = 1.0 (P = 0.020) though the inflammatory activity was not much different. No significant differences in HAI were noted among polymorphisms of other cytokines. Moreover, ALT and HCV RNA levels were not significantly different among different cvtokine polymorphisms. There was a significant correlation of HAI and HCV RNA levels with the duration of disease. TGFBBB -10 genotype CC patients had a better end of treatment response than those with other genotypes (P = 0.020). Sustained virological response to the treatment was not influenced by the cytokine polymorphism. No effect of other factors like viral load, degree of fibrosis, gender, steatosis, was observed on sustained virological response in this population infected with genotype 3. CONCLUSION: There is no significant correlation between cytokine polymorphisms and HAI except for the polymorphisms of anti-inflammatory cytokine IL-10, which may influence hepatic inflammatory activity and fibrosis in patients with chronic hepatitis C genotype 3. Sustained virological response in this genotype does not seem to be influenced by cytokine gene polymorphisms. 相似文献
18.
Jafri MR Nordstrom CW Murray JA Van Dyke CT Dierkhising RA Zinsmeister AR Melton LJ 《Digestive diseases and sciences》2008,53(4):964-971
Celiac disease is associated with decreased bone density, but there are conflicting data regarding fracture risk. We determined
the fracture incidence relative to matched controls in a population-based cohort with celiac disease before and after diagnosis.
Olmsted County residents with celiac disease (n = 83) diagnosed between 1950 and 2002 were compared with 166 gender and age matched controls. Fracture histories were ascertained
from each subject’s medical records. Celiac disease is linked to an increased fracture risk before and after diagnosis. Before
the index date, cases had a fracture rate twice that of controls (CI: 1.0–3.9, P = 0.045) and 2.5-fold greater after the index date (CI: 1.1–5.6, P = 0.026). Appendicular and axial fractures were 2.5 (CI: 0.9–6.5) and 3.2 times more likely (CI: 1.0–10.5) after the index
date. These observations support a rationale for earlier detection of celiac disease, and active management of bone disease
before bone effects have occurred, to reduce the persistent risk of fractures. 相似文献
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20.
M A Beg N Sani V Mehraj W Jafri M A Khan A Malik E Menezes R Hussain R Smego 《International journal of infectious diseases》2008,12(1):37-42
OBJECTIVES: A comparison of clinical and laboratory features, diagnostic methods, drug treatment, and outcomes for patients hospitalized with malaria by Plasmodium species. METHODS: Records of 521 patients hospitalized during the four and half-year study period were analyzed. RESULTS: Infections were caused by Plasmodium vivax (51.8%), Plasmodium falciparum (46.5%), P. vivax plus P. falciparum (1.3%), and Plasmodium malariae (0.4%). Vomiting (odds ratio (OR)=1.86, p=0.001) and abdominal pain (OR=1.60, p=0.024) occurred more frequently in patients infected with P. falciparum compared to P. vivax; this was also the case for hepatomegaly, splenomegaly and jaundice. Low hemoglobin levels were common but were significantly lower with P. falciparum, and creatinine levels were significantly higher with P. falciparum. Treatment regimens consisted of single drug therapy (61.5%), appropriate combination therapy (15.8%), and inappropriate combination therapy (22.7%). Antimalarials given alone included chloroquine (38.7%), quinine (19%) and doxycycline (1.5%). The overall mortality was 1.7% (n=9) and nearly 56% of patients developed disease complications, most commonly thrombocytopenia (36.4%), anemia (23.4%), and thrombocytopenia plus anemia (32.7%). CONCLUSIONS: Despite resistance, chloroquine was prescribed in patients with malaria requiring hospitalization. We found a high proportion of single antimalarial drug use as well as inappropriate combination therapy (22.7%), and inadequate use of primaquine terminal prophylaxis. Physicians need to be acquainted with malaria treatment guidelines in an endemic zone. 相似文献