Babesiosis diagnosis and treatment

Human babesiosis due to Babesia microti is an emerging malaria-like infection that is endemic in parts of the northeastern and northcentral United States. The clinical manifestations of babesiosis range from subclinical illness to fulminant disease resulting in death. Prompt and accurate diagnosis is difficult because the signs and symptoms are non-specific. A CBC is a useful screening test since anemia and thrombocytopenia are commonly observed and parasites may be visualized on blood smear. Conclusive diagnosis of this disease generally depends upon microscopic examination of thin blood smears. Babesia frequently are overlooked, however, because parasitemia tends to be sparse, often infecting fewer than 1% of erythrocytes early in the course of the illness. Identification of amplifiable babesial DNA by polymerase chain reaction (PCR) has comparable sensitivity and specificity to microscopic analysis of thin blood smear for detection of babesia in blood. Serologic testing provides useful supplementary evidence of infection because a robust antibody response characterizes human babesial infection, even at the time that parasitemia first becomes detectable. The currently recommended therapy for babesiosis is a 7-10-day course of clindamycin (600 mg every 6 h) and quinine (650 mg every 8 h). Recently, azithromycin (500-600 mg on day 1, and 250-600 mg on subsequent days) and atovaquone (750 mg every 12 h) was found to be equally effective in treating adults experiencing babesiosis. This combination also was associated with fewer adverse reactions than clindamycin and quinine. Exchange transfusion is a potentially life-saving therapy for patients suffering from severe disease with high parasitemia (>5%), significant hemolysis, or renal or pulmonary compromise. Babesiosis may be prevented by avoiding areas such as tall grass and brush where ticks, deer, and mice are known to thrive.     

1例人感染田鼠巴贝虫的实验室诊断及文献复习

目的 回顾1例反复发热半年,最终确诊为田鼠巴贝虫感染的诊断过程,复习文献,为巴贝虫病的诊断提供参考. 方法 收集患者的临床资料和流行病学资料,采集患者骨髓和外周血涂片镜检,抽提血液基因组DNA,用田鼠巴贝虫特异引物进行巢式PCR扩增,取血清进行间接免疫荧光检测. 结果 骨髓和外周血涂片镜检可见少量红细胞内有环状体,未见其它疟原虫红细胞内期形态.巢式PCR获得阳性条带,经测序证实为田鼠巴贝虫18s rRNA基因;间接免疫荧光抗体试验阳性;经克林霉素、磷酸氯喹片抗巴贝虫治疗2个疗程,患者达到临床治愈. 结论 综合患者临床资料、实验室检查结果、以及抗巴贝虫药物疗效,确诊1例人田鼠巴贝虫感染病例.在病原学检查不典型时,分子生物学和免疫学检查结果是重要的巴贝虫病诊断依据.     

Coexposure to Borrelia burgdorferi and Babesia microti does not worsen the long-term outcome of lyme disease.

Previous studies suggest that concurrent Lyme disease and babesiosis produce a more sever illness than either disease alone. The majority of babesiosis infections, however, are subclinical. Our objective was to characterize on the basis of a total-population survey of Nantucket Island, Massachusetts, whether coexposure to Lyme disease and babesiosis causes more severe illness or poorer long-term outcomes than Lyme disease alone. In this retrospective cohort study, residents indicating a history of Lyme disease were compared with randomly selected population controls on a standardized medical history, blinded physical examination, and serological studies for Borrelia burgdorferi and Babesia microti. Serological evidence of exposure to babesiosis was not associated with increased severity of acute Lyme disease. The groups did not differ with regard to the prevalence of constitutional, musculoskeletal, or neurological symptoms a mean of 6 years after acute Lyme disease. Prior Lyme disease and serological exposure to B. microti are not associated with poorer long-term outcomes or more persistent symptoms Lyme disease alone.     

First documentation of transfusion-associated babesiosis in Japan

A 40-year-old man received blood transfusion in December 1998 because of gastric bleeding from a peptic ulcer. One month later, he developed febrile hemolytic anemia. Administration of high doses of glucocorticoid significantly reduced the hemolysis, but did not cure the disease. To investigate the cause of the hemolysis, the patient was transferred to our hospital in May 1999. Giemsa-stained peripheral blood smears showed Babesia parasites in the red blood cells (RBC), and PCR analysis confirmed the presence of Babesia microti DNA. The parasitemia disappeared hematologically after 2 weeks of quinine and clindamycin therapy. However, parasite DNA was still detectable in the RBC. Although treatment with oral atovaquone was given for 2 weeks, parasitemia and febrile hemolysis recurred within a month after the last treatment. Fortunately, complete remission was obtained after a second 12-week course of therapy with quinine and clindamycin. PCR analysis revealed asymptomatic Babesia infection in one of eight samples from the original blood donor. The initial steroid therapy given to the patient without an accurate diagnosis seemed to have delayed augmentation of the specific antibodies (IgG) against Babesia microti, thus prolonging the parasitemia after the initial acute stage of babesiosis.     

Age-associated decline in resistance to Babesia microti is genetically determined

BACKGROUND: Although infection by the protozoan Babesia microti is rarely symptomatic in immunocompetent young people, healthy individuals aged >50 years may experience life-threatening disease. To determine the basis for this age relationship, we developed a mouse model of babesiosis using a novel clinical isolate of B. microti. METHODS: Mice were infected at 2, 6, 12, or 18 months. Parasitemia was monitored on Giemsa-stained blood smears or by flow cytometry. RESULTS: In DBA/2 mice, early and persistent parasitemias increased with age at infection. BALB/c and C57BL/6 mice were resistant, regardless of age, which indicates that allelic variation determines resistance to B. microti. Unlike immunocompetent mice, SCID mice, which retain an innate immune system but lack the lymphocytes needed for adaptive immunity, developed high and persistent levels of parasitemia that were markedly reduced by transfer of naive BALB/c or DBA/2 splenocytes. BALB/c cells reduced the persistent parasitemia to a greater extent than did age-matched DBA/2 cells. Of importance, there was an age-associated loss of protection by cells of both strains. CONCLUSION: The resistance to B. microti infection conferred by the adaptive immune system is genetically determined and associated with age. We postulate that there are age-related differences in the expression of alleles critical for adaptive immunity to B. microti.     

我国巴贝虫病流行现状与研究进展

巴贝虫病是由巴贝虫感染引起的一类人兽共患寄生虫病。巴贝虫经蜱叮咬、输血或器官移植等途径传播,主要寄生于人或其他脊椎动物红细胞内。感染人体的巴贝虫主要有田鼠巴贝虫、猎户巴贝虫、邓肯巴贝虫、分歧巴贝虫等。巴贝虫病呈世界性分布,多发于夏秋季节,在我国属于新发、罕见寄生虫病。过去临床上缺乏敏感有效的诊断方法,导致很多巴贝虫病患者未能得到及时治疗。随着高敏感性的分子生物学检测技术在临床上的应用,巴贝虫病病例报告数量逐渐增多。本文详细回顾了1943年至今我国人巴贝虫病病例报告情况,概述了巴贝虫病诊断、治疗和致病机制等方面的研究进展,分析了我国巴贝虫病防控的挑战和前景。     

Patterns of antimicrobial use among nursing home residents with advanced dementia

BACKGROUND: Nursing home residents with advanced dementia are at high risk of infections and antimicrobial exposure near the end of life. Detailed studies quantifying antimicrobial prescribing practices among these residents have not been performed. METHODS: A cohort of 214 residents with advanced dementia from 21 Boston-area nursing homes were followed up prospectively for 18 months or until death. We analyzed antimicrobial use, including type, indication, and quantity, by days of therapy per 1000 resident-days. RESULTS: During an average of 322 days of follow-up, 142 residents (66.4%) with advanced dementia received at least 1 course of antimicrobial therapy (mean [SD] number of courses per resident, 4.0 [3.7]). The mean (SD) number of days of therapy per 1000 resident-days for the entire cohort was 53.0 (4.3). Quinolones and third-generation cephalosporins were the most commonly prescribed antimicrobials, accounting for 38.3% and 15.2%, respectively, of 540 prescribed antimicrobial therapy courses. A respiratory tract infection was the most common indication (46.7% of all antimicrobial therapy courses). Among 99 decedents, 42 (42.4%) received antimicrobials during the 2 weeks before death, of which 30 of 72 courses (41.7%) were administered via the parenteral route. The number of decedents receiving antimicrobials (P < .001), the number of antimicrobials prescribed (P = .01), and the days of therapy per 1000 resident-days (P < .001) increased significantly as subjects approached death. CONCLUSIONS: Persons with advanced dementia are frequently exposed to antimicrobials, especially during the 2 weeks before death. The implications of this practice from the perspective of the individual treatment burden near the end of life and its contribution to the emergence of antimicrobial resistance in the nursing home setting need further evaluation.     

Treatment of refractory Babesia microti infection with atovaquone-proguanil in an HIV-infected patient: case report.

A patient with acquired immune deficiency syndrome presented with babesiosis 6 months after presumed tick exposure. Despite initial treatment with azithromycin and atovaquone, followed by quinine and clindamycin, he experienced an increasing parasite load. Finally, red blood cell exchange transfusion, anti-Babesia therapy, and the addition of atovaquone-proguanil to the treatment regimen led to symptomatic improvement and elimination of parasitemia. Low-level parasitemia recurred 20 weeks later and was eradicated by administration of atovaquone-proguanil monotherapy. Atovaquone-proguanil appears to have activity against babesiosis and should be studied as a potential therapy for patients with refractory babesiosis.     

Babesiosis: an emerging infectious disease that can affect those who travel to the northeastern United States

A case is presented of a healthy, 57 year-old male living in Ohio who traveled to Connecticut and later developed a severe case of babesiosis. The patient presented to his primary care physician with a history of intermittent fever and myalgias and was admitted to the hospital for investigation. On admission, he was found to have fever, left flank pain, and thrombocytopenia. The patient had an intact spleen, had no significant medical history, and had not received any blood products previously. During hospitalization, the patient developed pancytopenia and jaundice and became progressively more ill. A serendipitous conversation led to the investigation into babesiosis and empiric treatment. Infection with Babesia microti was confirmed by blood smear and PCR. In conclusion, obtaining a domestic, as well as international, travel history is important for identifying diseases, such as babesiosis, endemic to other areas.     

Rescue therapy using a rifabutin-based regimen is effective for cure of Helicobacter pylori infection

OBJECTIVE:

To evaluate the efficacy of rescue therapy using rifabutin, amoxicillin and a proton pump inhibitor (PPI) in the eradication of Helicobacter pylori in patients who have failed at least one course of PPI-based triple therapy.

METHODS:

The present study was a single-centre case series of 16 consecutive patients who had received at least one course of standard eradication therapy. Pretreatment evaluation included endoscopy with biopsies for histology and culture for H pylori infection. Treatment consisted of a one-week regimen containing a PPI twice daily, amoxicillin (A) 1 g twice daily and rifabutin (R) 300 mg once daily (PPI-AR). Post-treatment evaluation consisted of a repeat endoscopy with biopsy for histology and culture, or a validated urea breath test at least four weeks after treatment was completed. Pretreatment antibiotic susceptibility to metronidazole, clarithromycin and A was evaluated using a validated epsilometer test.

RESULTS:

Of the 16 patients, four had previously received one course of triple therapy, 10 had received two courses and two had received more than two courses. The overall success rate of PPI-AR was 63% (10 of 16). Resistance to A was 0% (0 of 13), metronidazole 77% (10 of 13), clarithromycin 70% (seven of 10), and both metronidazole and clarithromycin 60% (six of 10). There was no correlation between resistance patterns and cure rate.

CONCLUSIONS:

An R-containing regimen such as PPI-AR is a viable option as rescue therapy for H pylori infection.     

Infectious disease management of adult leukemic patients undergoing chemotherapy: 1982 to 1986 experience at Stanford University Hospital

PURPOSE: The purpose of this study was to determine the recent incidence of infection and to evaluate antimicrobial usage among adult leukemic patients undergoing chemotherapy for acute myelogenous leukemia (AML) and acute lymphoblastic leukemia (ALL) at Stanford University Hospital. PATIENTS AND METHODS: The records of 142 adult patients from a consecutive series of 226 induction or consolidation/maintenance chemotherapy courses for AML or ALL between 1982 to 1986 were reviewed retrospectively. Data were analyzed to compare the infectious disease complications and antimicrobial usage for patients receiving identical chemotherapy for a specific phase of leukemia treatment. Evaluation for each chemotherapy course included assessments for the following: compliance with criteria for initiating antibiotics, incidence of infection that was documented by culture or clinical criteria, predictive value of surveillance cultures, incidence of superinfection, survival outcomes, antimicrobial usage, antibiotic-related adverse effects, and cost for antibiotics and diagnostic studies. RESULTS: Antimicrobials were employed in 190 (84%) of 226 chemotherapy courses. Broad-spectrum antibiotics were regularly begun within the first five days of admission and they were continued for an average of 3.5 weeks until the granulocyte count was greater than 1,000/microL after discontinuation of chemotherapy. There were no differences in the types of infection or outcomes among the patient groups. There was only a 37% rate of documented infections by culture or clinical signs among these patients during their entire hospital stay. Bacterial infections, especially those caused by coagulase-negative staphylococci in patients with Hickman catheters, accounted for 93% of the episodes. Viral and fungal infections accounted for 4% and 3% of documented cases, respectively, and occurred more than 10 days after the institution of broad-spectrum antibiotic therapy. A total of 922 different antimicrobials were employed in 190 courses (average 4.9 per course). The rationale for excessive usage and multiple changes was a persistent or intermittent fever, rather than documented infection(s). This practice led to usage of more broad-spectrum and expensive antibiotics. Further analyses indicate that the greater number of antibiotics employed correlated with apparent increased toxicity, especially renal and hepatic adverse reactions. These toxicities were associated with higher rates of fatal outcomes, i.e., 12 (39%) of 31 patients died with antibiotic-associated hepatic and/or renal insufficiency, compared with 12 (7.5%) of 159 patients who died without antibiotic-associated organ damage. CONCLUSION: Excessive antibiotic usage and multiple antibiotic changes among adult leukemic patients undergoing chemotherapy appear to increase the risks of adverse hepatic and renal effects and death. Furthermore, this practice leads to use of more broad-spectrum and expensive antibiotics...     

Inappropriate initial antimicrobial therapy and its effect on survival in a clinical trial of immunomodulating therapy for severe sepsis

PURPOSE: To examine the effect of inappropriate initial antimicrobial therapy on the prognosis of patients with sepsis who were enrolled in a clinical trial of an immunomodulating agent conducted in 108 hospitals in North America and Europe. METHODS: We assessed initial antimicrobial choice and results of microbiologic cultures in 904 patients who had microbiologically confirmed severe sepsis or early septic shock. If a patient did not receive at least one antimicrobial agent to which the causative microorganisms were susceptible within 24 hours from the diagnosis of severe sepsis, then the initial antimicrobial treatment was considered to be inappropriate. A propensity score that adjusted for factors associated with inappropriate antimicrobial treatment was calculated and included in multivariable models to adjust for confounding. RESULTS: A total of 468 patients (52%) had documented bloodstream infection, and 211 patients (23%) received inappropriate initial antimicrobial therapy. Characteristics associated with inappropriate treatment were study enrollment in Europe, admission to surgery, nosocomial infection, infection with multiresistant microorganisms, and fungal or polymicrobial infection (all P <0.05). The 28-day mortality was 24% (168/693) for patients in the adequately treated group versus 39% (82/211) for patients receiving inappropriate initial antimicrobial therapy (P <0.001). After adjusting for comorbid conditions, severity of illness, site of infection, and the propensity score, inappropriate antimicrobial therapy was independently associated with increased mortality (odds ratio = 1.8; 95% confidence interval: 1.2 to 2.6). CONCLUSION: In a large cohort of patients with microbiologically confirmed severe sepsis, appropriate initial antimicrobial therapy was an important determinant of survival. New approaches aimed at improving detection and treatment of early sepsis are needed.     

福建省1例人巴贝虫病的诊断与鉴定

目的 分析1例人感染巴贝虫的实验室资料,提高对巴贝西虫病的诊断水平。方法 观察外周血中虫体的形态;从患者外周血中提取的DNA核酸,采用田鼠巴贝虫种特异性引物进行聚合酶链反应(PCR)。采用PCR扩增田鼠巴贝虫18S rRNA片段,取阳性PCR产物送测序并进行序列比对分析。结果 外周血中见大量疑似恶性疟原虫虫体;PCR产物测序结果经过BLAST比对,与田鼠巴贝虫18s核糖体DNA序列有99%的同源性。结论 感染的虫体为田鼠巴贝虫。福建省部分地区鼠类(尤其是野鼠)存在田鼠巴贝虫感染,是巴贝虫病的自然疫源地,必须引起足够的重视。     

Efficacy of levofloxacin-based triple therapy as second-line Helicobacter pylori eradication]

BACKGROUND/AIMS: Bismuth-based quadruple therapy for second-line eradication treatment achieves the eradication rate ranging from 70% to 81% due to antimicrobial resistance and poor compliance. The aim of this study was to compare the eradication rate of levofloxacin-based triple therapy with that of bismuth-based quadruple therapy in second-line Helicobacter pylori (H. pylori) eradication therapy. METHODS: Seventy-six outpatients with persistent H. pylori infection after first-line triple therapy were enrolled in this prospective randomized trial. The subjects were randomized to receive levofloxacin 300 mg, amoxicillin 1 g, and pantoprazole 20 mg, given twice daily for 7 days (LAP group), or metronidazole 500 mg twice, tetracycline 500 mg four times, and pantoprazole 20 mg twice, bismuth subcitrate 600 mg twice daily for 7 days (MTPB group). Eradication was confirmed with (13)C-urea breath test or rapid urease test 4 weeks after the cessation of therapy. RESULTS: Among Seventy-six patients initially included, eleven were lost during follow-up. The eradication rates, expressed as intention to treat (ITT) and per protocol (PP) analyses, were 51.6% and 53.3% in the LAP group, and 48.9% and 62.9% in the MTPB group, respectively. There was no significant difference in H. pylori eradication rates between the two groups (p=0.815 by ITT, p=0.437 by PP). LAP regimen was better tolerated than MTPB regimen with lower incidence of side effects (10.0% versus 31.4%, p=0.03). CONCLUSIONS: H. pylori eradication rates of levofloxacin-based triple therapy and bismuth-based quadruple therapy were not significantly different in second-line H. pylori eradication therapy, and low incidence of side effects was observed in levofloxacin-based triple therapy.     

Prosthetic joint infection due to rapidly growing mycobacteria: report of 8 cases and review of the literature.

BACKGROUND: Prosthetic joint infection (PJI) due to rapidly growing mycobacteria (RGM) is only occasionally encountered in clinical practice. Therefore, the optimal clinical management for this condition is unknown. METHODS: The medical records of patients who had PJI due to RGM during 1969-2006 were reviewed to summarize its clinical characteristics, treatment, and outcome. RESULTS: Eight patients developed 9 episodes of PJI (7 episodes involving the knee and 1 each involving the hip or elbow) due to RGM at a median of 312 weeks (range, 1-170 weeks) after prosthesis implantation. Patients presented with joint pain (7 patients), joint swelling (7 patients), and fever (3 patients), accompanied by an elevated erythrocyte sedimentation rate (median, 70.5 mm/h) and C-reactive protein level (median, 6 mg/dL). Mycobacterium chelonae (n=3), Mycobacterium abscessus (n=2), Mycobacterium fortuitum (n=3), and Mycobacterium smegmatis (n=1) were isolated from the 9 infected joints. Seven of 9 prostheses were resected, whereas 2 were retained after surgical debridement. Six of 8 patients received > or = 1 active antimicrobial agent for at least 6 months. During a median follow-up period of 33 weeks (range, 2.6-326 weeks) after surgical intervention, no clinical or microbiological relapses were observed. Reimplantation was performed successfully for 2 of 6 patients who underwent resection arthroplasty. The 2 patients with retained prosthesis continued to receive prolonged courses of suppressive antimicrobial therapy. CONCLUSIONS: RGM is a rare cause of PJI that should be suspected in patients with negative results of routine bacterial cultures. The combination of resection arthroplasty and antimicrobial therapy is the preferred approach. However, in cases involving retained prosthetic components, RGM infection may be suppressed with lifelong courses of effective antibiotic therapy.     

Triple therapy with clarithromycin, amoxicillin and omeprazole for Helicobacter pylori eradication in children and adolescents

BACKGROUND: Helicobacter pylori infection presents high prevalence in developing countries, but there are few pediatric assays evaluating antimicrobial treatment. OBJECTIVE: The aim of this study was to investigate Helicobacter pylori eradication rate using a short regimen (7 and 10 days) of triple therapy with clarithromycin, amoxicillin and omeprazole. PATIENTS AND METHODS: Twenty-five Hp positive patients who presented severe epigastralgia, were submitted to antimicrobial treatment with amoxicillin (50 mg/kg/day--maximum dose 1 g bid), clarithromycin (30 mg/kg/day--maximum dose 500 mg bid) and omeprazole (0.6 mg/kg/day--maximum dose 20 mg bid) during 7 or 10 days. After 2 months, clinical symptoms were evaluated and gastric biopsies were taken to test Hp eradication. RESULTS: Overall eradication rate was achieved in 16/25 patients (64%--IC(95% = 45-83%), in 11/15 (73%--IC(95%) = 51-95%) patients who used 10 days therapy course and in 5/10 (50%--IC(95%) = 19-81%) who used 7 days therapy course. Eradication drugs were well accepted and adverse effects were reported in two patients (8%). CONCLUSIONS: This triple therapy regimen had moderate efficacy (64%). The data suggests that 10 days therapy course achieves better eradication rate (73%) than 7 days course (50%) to treat Hp infection in our population.     

Serious infectious complications of midsternotomy: a review of bacteriology and antimicrobial therapy

49 patients with severe infectious complications of midsternotomy incision were treated at our referral center over a 3-year period. 43 species of microorganisms were identified in 38 patients, the most common being Pseudomonas aeruginosa (37%) and Staphylococcus aureus (30%). Most of the patients underwent aggressive debridement and chest wall reconstruction by muscle transposition in combination with antimicrobial therapy. Antimicrobial therapy was given perioperatively according to the in vitro susceptibility of the organisms. Treatment was continued beyond this period for 2-3 weeks in patients with extensive deep seated infection or in those with positive cultures from intraoperative specimens. Some patients needed a longer course of up to 6-8 weeks antimicrobial therapy because of insufficient response to the shorter course. In all, 45/49 patients had complete wound healing. 28 recovered within 2-5 weeks and 16 required a more protracted course with additional surgery in 8; 1 wound did not heal after 20 months and 4 patients died from non-infectious complications. Due to the lack of specific guidelines in the literature as to the proper choice and length of administration of antimicrobial therapy for midsternotomy wound infection, and in view of these favorable results, we recommend our protocol in the treatment of midsternotomy wound infection (in combination with appropriate surgery).     

幽门螺杆菌根除治疗失败后的补救治疗

幽门螺杆菌（H.pylori)对抗生素的耐药率上升是导致根除治疗失败率上升的主要原因，对经标准方案根除H.pylori失败的患者有必要进行补救治疗。目的：评估铋剂、质子泵抑制剂（PPI）联用呋喃唑酮和四环素组成的7天四联方案用于根除H.pylori治疗失败后补救治疗的疗效，以及H.pylori耐药对疗效的影响。方法：予35例经含克拉霉素根除H.pylori方案治疗、H.pylori仍为阳性的患者以为期7天的四联治疗：枸橼酸铋钾220mg bid 奥美拉唑20mg bid 呋喃唑酮100mg bid 四环素750mg bid。治疗前取胃窦黏膜活检标本进行快速尿素酶试验、组织学检查和培养检测H.pylori。用琼脂扩散法测定克拉霉素、呋喃唑酮和四环素的最低抑菌浓度（MIC）。治疗结束后至少4周，采用^13C-尿素呼气试验进行H.pylori感染状态评估。结果：33例患者完成治疗和随访，2例失访。根据意图治疗（ITT）和试验方案（PP）分析，该补救方案的H.pylori根除率分别为68．6％（24／35）和72．7％（24／33）。10例（28．6％）患者发生轻度副反应（9例发生恶心、中上腹不适，1例发生皮疹）。35例中有27例H.pylori培养成功，克拉霉素的耐药率为51．8％（14／27），呋喃唑酮为3．7％（1／27），四环素为7．4％（2／27）。各药物耐药菌株和敏感菌株的H.pylori根除率无显著差异。结论：铋剂、PPI联用呋喃唑酮和四环素组成的7天联方案作为根除H.pylori治疗失败后的补救治疗可获得较高的H.pylori根除率。     

Treatment of Helicobacter pylori infection]

Significant progress and new insights have been gained since Helicobacter pylori was found in 1982. Even with currently most effective treatment regimen, about 10-20% of patients will fail to obtain the eradication of H. pylori infection. This review will focus on the empirical treatment for H. pylori infection in Korea. Seven days triple therapy (proton pump inhibitor, amoxicillin and clarithromycin) has been the main first line therapy for H. pylori infection in Korea after the recommendation by Korean H. pylori study group in 1998. Such triple therapy has been the effective regimen for eradication of H. pylori infection. However, the efficacy of 7 days proton pump inhibitor-amoxicillin-clarithromycin therapy becomes lower and various eradication rates probably reflects the increase in antimicrobial resistance, recently. The recent multi-center prospective randomized study and meta-analysis showed 14 days proton pump inhibitor-amoxicillin-clarithromycin therapy is more effective than 7 days or 10 days therapy. In the case of failure, quadruple therapy (proton pump inhibitor, a bismuth salt, metronidazole and tetracycline) is a very effective second-line regimen. After the failure of two or more eradication treatments, bacterial resistance to antibiotics should be evaluated and the regimen of third-line therapy should be selected according to each antimicrobial susceptibility. The empirical third-line therapies, recommended in the cases that antimicrobial susceptibility test is unavailable, are unclear of its validity at present in Korea. The triple therapies including rifabutin, moxifloxacin, or levofloxacin or dual therapy including high dose proton pump inhibitor and amoxicillin are needed to be proven as possible candidates for the empirical third-line therapy. Multiple eradication failures should be handled on a case-by-case basis by specialists.     

Levofloxacin- versus metronidazole-based rescue therapy for H. pylori infection in Japan

BACKGROUND: The ideal second-line treatment regimens for Helicobacter pylori infection may differ between the areas, countries and races. AIM: The aim was to confirm which was the better regimen for second-line therapy after treatment failure with a standard triple therapy in Japan, a high dosage of levofloxacin- or metronidazole-based therapy. PATIENTS: Sixty outpatients with persistent H. pylori infection after a standard triple therapy were enrolled in this prospective, open-label and randomised trial. METHODS: The subjects were randomly administered levofloxacin (300 mg b.d.)- or metronidazole (500 mg b.d.)-based therapy with lansoprazole (30 mg b.d.) and amoxicillin (1000 mg b.d.) for 7 days, and the cure rates and side effects were analysed. Antimicrobial susceptibility was also examined before second-line therapy using the E-test. RESULTS: Good compliance was obtained without severe side effects in both the groups except for two patients. The cure rates, expressed as intention-to-treat and per-protocol analyses, respectively, were 70.0 and 72.4% in the levofloxacin group, and 96.7 and 100% in the metronidazole group. Each regimen often overcame even clarithromycin-resistant strains. CONCLUSION: Metronidazole-based triple therapy is recommended as second-line therapy in Japan, and levofloxacin-based therapy can be an alternative treatment option.