Helicobacter pylori antimicrobial resistance and antibiotic consumption in the low-resource Central America setting

BACKGROUND

Antimicrobial resistance is a global public health problem, particularly in low- and middle-income countries (LMICs), where antibiotics are often obtained without a prescription. H. pylori antimicrobial resistance patterns are informative for patient care and gastric cancer prevention programs, have been shown to correlate with general antimicrobial consumption, and may guide antimicrobial stewardship programs in LMICs. We report H. pylori resistance and antimicrobial utilization patterns for western Honduras, representative of rural Central America.

METHODS

In the context of the western Honduras gastric cancer epidemiology initiative, gastric biopsies from 189 patients were studied for culture and resistance patterns. Antimicrobial utilization was investigated for common H. pylori treatment regimens from regional public (7 antimicrobials) and national private (4 antimicrobials) data, analyzed in accordance with WHO anatomical therapeutic chemical defined daily doses (DDD) method and expressed as DDD/1000 inhabitants per day (DID) and per year (DIY).

RESULTS

H. pylori was successfully cultured from 116 patients (56% males, mean age: 54), and nearly all strains were cagA+ and vacAs1m1+ positive (99% and 90.4%, respectively). Unexpectedly, high resistance was noted for levofloxacin (20.9%) and amoxicillin (10.7%), while metronidazole (67.9%) and clarithromycin (11.2%) were similar to data from Latin America. Significant associations with age, gender, or histology were not noted, with the exception of levofloxacin (28%, P = 0.01) in those with histology limited to non-atrophic gastritis. Total antimicrobial usage in western Honduras of amoxicillin (17.3 DID) and the quinolones had the highest relative utilizations compared with other representative nations.

CONCLUSIONS

We observed significant H. pylori resistance to amoxicillin and levofloxacin in the context of high community antimicrobial utilization. This has implications in Central America for H. pylori treatment guidelines as well as antimicrobial stewardship programs.

Proximal row carpectomy on manual workers: 17 patients followed for an average of 6 years

Proximal row carpectomy (PRC) is indicated for the treatment of SNAC or SLAC wrist with preservation of the midcarpal joint. Our hypothesis was that PRC is not appropriate for treating advanced wrist osteoarthritis in patients who carry out heavy manual work. Twenty-three PRCs were performed on 21 patients, 5 women and 16 men with an average age of 54 years (33-77). All patients performed manual work; 11 of them performed heavy manual work. Etiologies were: SLAC wrist in 14 cases (2 stage III, 11 stage II, and 1 stage I) and SNAC wrist in 9 cases (6 stage IIIB and 3 stage IIB). At an average 75 months' follow-up (24-153), five patients were lost to follow-up. Radiocarpal arthrodesis was performed in one patient 10 years after the PRC. In the 17 remaining patients (18 wrists), pain (VAS) averaged 2.2, with residual pain of 5. Flexion-extension range was similar to preoperative levels (67% of contralateral wrist). Wrist strength was decreased by 34% compared to preoperative. The QuickDASH score averaged 26 points and the PRWE 20 points. Radiocapitate distance decreased by 0.3mm on average with joint line narrowing in 6 patients. The carpal translation index was 0.33mm, which was unchanged relative to preoperative values. Three patients had work-related limitations that required retraining and one patient had to be reassigned. PRC preserved the preoperative range of motion and reduced pain levels. However, significant loss of strength was observed, resulting in 23% of manual workers needing retraining or reassignment.

TYPE OF STUDY/LEVEL OF EVIDENCE

Therapeutic IV.

Durability And Microstructure of Pore Reduced Cements(PRC)

The pore structure characteristics of cementitious materials play an important role in defining their mechanical and durability performance. The mechanical properties of pore reduced cements (PRC) have already been reported [5] as a function of the product density. This paper reports recent data on the durability of PRC and attempts to relate the pore properties of the material to its resistance against deterioration in aggressive environments.

End-of-treatment but not interim PET scan predicts outcome in nonbulky limited-stage Hodgkin's lymphoma

BACKGROUND

Early interim positron emission tomography (PET) scans appear powerfully predictive of outcome in Hodgkin's lymphoma (HL), particularly in advanced-stage disease where it has been predominantly studied. The prognostic value of interim PET in limited-stage patients with nonbulky disease has not been well established.

PATIENTS AND METHODS

Ninety-six patients with nonbulky limited-stage HL were identified who had interim and end-of-treatment PET scans. Response rate, overall survival (OS), and progression-free survival (PFS) were calculated.

RESULTS

Four-year PFS and OS for the entire cohort were 88% and 97%, respectively. Interim PET did not predict outcome, with PFS in positive and negative patients 87% versus 91% (P=0.57), respectively. End-of-treatment PET result was predictive of outcome, with PFS of 94% in end PET-negative patients versus 54% in end PET-positive patients (P<0.0001). Four-year OS was 100% in end PET-negative patients and 84% in end PET-positive patients (P<0.0001).

CONCLUSIONS

Interim PET scans were not predictive of outcome, compared with scans carried out at completion of therapy. End-of-treatment PET was highly predictive of PFS and OS, regardless of interim PET result. In this low-risk patient population, even patients with interim positive PET scans show a favorable prognosis.

Interleukin 10 (IL-10) gene variants and susceptibility for paediatric onset Crohn's disease

BACKGROUND

A recent genome-wide association study in adult patients with ulcerative colitis (UC) has implicated the interleukin 10 (IL-10) gene as an important candidate gene. Moreover, a UC-associated single nucleotide polymorphism (SNP) rs3024405 was also significantly associated with adult Crohn's disease (CD).

AIMS

To examine whether IL-10-CD associations extended to paediatric-onset CD.

METHODS

We implemented the case-control design at three paediatric gastroenterology clinics in Canada. CD patients (<or=20 years) were recruited along with healthy controls. DNA samples were genotyped for tag-single nucleotide polymorphisms (tag-SNPs) in the IL-10 gene. Allelic, genotype and haplotype associations with CD were studied.

RESULTS

A total of 270 patients and 336 controls were studied. The mean age (+/-s.d.) at diagnosis was 12.1 (+/-3.5). There were a slightly higher proportion of male patients (56.3%). Of the five IL-10 tag-SNPs, rs2222202 (C/T) (P = 0.03) and rs1800871 (C/T) (P = 0.05) showed significant allelic associations with CD. Specific IL-10 SNPs were associated with CD disease location and/or disease behaviour.

CONCLUSIONS

Our gene-wide analysis replicates recent findings of associations between IL-10 and adult CD, and suggests that these associations extend to paediatric-onset CD as well.

Natural variation in populations of persistently colonizing bacteria affect human host cell phenotype

The highly diverse bacterium Helicobacter pylori, which persistently colonizes the human stomach, provides models to study the role of genome plasticity in host adaptation. Within H. pylori populations from 2 colonized individuals, intragenomic recombination between cagA DNA repeat sequences leads to deletion or duplication of tyrosine phosphorylation sites in the CagA protein, which is injected by a type IV secretion system into host cells. Experimental coculture of gastric epithelial cells with the strains containing these naturally occurring CagA phosphorylation site variants induced markedly divergent host cell morphologic responses. Mutants were constructed in which a phosphorylation site was either added or deleted in the expressed CagA protein; coculture studies confirmed that the naturally occurring differences in CagA phosphorylation are responsible for the observed phenotypic variation. These findings indicate that within an individual host, intragenomic recombination between H. pylori repetitive DNA produces strain variants differing in their signals to host cells.

Omeprazole for treatment of chronic erosive esophagitis in children: a multicenter study of efficacy, safety, tolerability and dose requirements. International Pediatric Omeprazole Study Group

OBJECTIVES

To determine the efficacy, safety, and tolerability of omeprazole in children and to determine the doses required to heal chronic, severe esophagitis.

STUDY DESIGN

Open multicenter study in children aged 1 to 16 years with erosive reflux esophagitis. The healing dose of omeprazole used was that with which the duration of acid reflux was <6% of a 24-hour intraesophageal pH study. Follow-up endoscopy was performed after 3 months of treatment with the healing dose.

RESULTS

At entry, two thirds of 57 patients who completed the study had esophagitis grade 3 or 4 (scale 0-4); some 50% had neurologic impairment or repaired esophageal atresia. Of the 57 patients, 54 healed; 3 did not heal and left the study, and 3 healed with a second course. Doses required for healing were 0.7 to 3.5 mg/kg/d: 0.7 mg/kg/d in 44% of patients and 1.4 mg/kg/d in another 28%. Healing dose correlated with grade of esophagitis but not with age or underlying disease. Reflux symptoms improved dramatically in almost all of the 57 patients, including the unhealed patients.

CONCLUSIONS

Omeprazole is well tolerated, highly effective, and safe for treatment of erosive esophagitis and symptoms of gastroesophageal reflux in children, including children in whom antireflux surgery or other medical therapy has failed. On a per-kilogram basis, the doses of omeprazole required to heal erosive esophagitis are much greater than those required for adults.

Overview of protease inhibitors

PURPOSE

To provide a basic review of the four currently available protease inhibitors: saquinavir, ritonavir, indinavir, and nelfinavir. Included are sections on surrogate markers of HIV disease and resistance to protease inhibitor therapy, as well as dosing information, pharmacokinetics, studies, adverse effects, and drug interaction potential.

DATA SOURCES

Conducted a review of published literature (MEDLINE), abstracts from national meetings and conferences, and product labeling and information available at the time of preparation through July 1997.

STUDY SELECTION AND DATA EXTRACTION

Material was selected for inclusion based on relevance to objectives, publication in English, and presence of useful information for practicing pharmacists.

DATA SYNTHESIS

Limited published information is currently available on the protease inhibitors, especially with regard to randomized, controlled, comparative trials and establishment of guidelines for direct therapy. Much of the available information relies heavily on product information and trials that are published only in abstract form. The evaluation of the protease inhibitors (with regard to place in therapy as well as resistance and toxicities) is an ongoing process.

CONCLUSION

Protease inhibitors have changed opinions about the futility of the treatment of HIV disease. Protease inhibitors dramatically improve patients' surrogate markers and even show mortality benefits, especially when combined with additional antiretroviral agents. The optimism surrounding these new drugs is tempered by the toxicity profile, development of resistance, drug interaction profiles, and added costs to current regimens. Designing tolerable, effective regimens will require careful monitoring for compliance, adverse effects, and potential drug interactions.

Herbal therapies for perimenopausal and menopausal complaints

Consumer use of alternative medicines in the United States is growing rapidly. Included in this phenomenon are herbal therapies instead of or as adjuncts with traditional medicine for perimenopausal and menopausal complaints. Of significant concern is the safety of these herbs. Since many women are using herbal therapies, clinicians must be knowledgeable about their use, quality, and safety. There are currently no government standards on the quality of herbal products in the United States, and some products are either unsafe or little is known scientifically about them. Selected herbal therapies touted in the lay press for common perimenopausal and menopausal complaints are examined, with advice on their use and safety based on scientific sources.

Multimode polymeric Y junctions for star couplers in backplane optical interconnect

Three different multimode polymeric Y junctions with 50:50 splitting ratios were designed and their performance analyzed with ray tracing and measurements. There is agreement between measurements and modeling. The best performance is found for a Y junction in which the waveguide is split to S bends with 50% widths.

Prospective evaluation of a stiff shaft glide wire compared with the standard straight wire in crossing severely stenotic aortic valves

In this prospective randomized study of the use of the Terumo glide wire compared with the standard straight wire for crossing of severely stenotic aortic valves, the glide wire was shown to significantly decrease the fluoroscopy time of the procedure and to lower by 3.4 times the need for crossover to the alternative technique.

Adaptation mechanisms during myocardial ischemia in chronic unstable angina pectoris

Unstable angina with a clinical duration of < 2 months is characterized angiographically by a high incidence of complex lesions. Some patients have ischemic rest pain syndromes of longer duration. Thus, we retrospectively analyzed, in blinded fashion, the clinical and angiographic findings in 52 patients with unstable angina of < 2 months' duration (group A), and compared the results with those of 32 patients with unstable angina of > 6 months' duration (group B). Group B had a greater number of diseased vessels and better collateral circulation, but had fewer eccentric lesions. There were no differences in age, left ventricular function, or history of prior myocardial infarction. Thus, chronic unstable angina is associated with more extensive coronary disease than unstable angina of shorter duration. The role of different anatomic substrata and collateral circulation is discussed.

Vancomycin skin tests and prediction of "red man syndrome" in healthy volunteers

The purpose of the present study was to assess the cutaneous response to intradermally administered vancomycin in healthy adults and to determine whether the magnitude of the cutaneous response correlated to the severity of "red man syndrome" (RMS) following intravenous administration of vancomycin to the same subjects. Eleven healthy males were skin tested with intradermally administered histamine and saline controls and intradermally administered vancomycin at different concentrations. Vancomycin caused a dose-dependent area of flare in all subjects. The sigmoidal maximal flare model was used to fit each dose-response curve, and cutaneous responsiveness to vancomycin was quantified by various methods, including the flare area at each dose, maximum flare area (maximal flare), dose required to produce 50% of maximum flare, dose required to produce a flare area of 400 mm2, and the slope of the dose-response curve. One week after skin testing, subjects received an infusion of vancomycin, 15 mg/kg of body weight over 60 min. For the assessment of the severity of RMS, we used previously described methods. Although all subjects experienced erythema from the intravenously administered vancomycin and 10 subjects had pruritus, there was no significant correlation between vancomycin skin test results and the severity of RMS. We conclude that vancomycin skin tests do not predict the severity of RMS. In addition, vancomycin skin tests may be of no benefit for assessing immunoglobulin E-mediated allergy to vancomycin, since all subjects had a positive reaction at concentrations of > or = 10 micrograms/ml.

Pharmacokinetics and serum bactericidal titers of ciprofloxacin and ofloxacin following multiple oral doses in healthy volunteers

Fourteen adult males participated in a randomized three-way crossover study to compare the pharmacokinetics and serum bactericidal titers (SBTs) of 500 mg of ciprofloxacin (regimen A), 750 mg of ciprofloxacin (regimen B), and 400 mg of ofloxacin (regimen C) administered every 12 h for seven doses. Mean steady-state peak concentrations in serum for regimens A, B, and C were 3.0, 4.4, and 6.5 micrograms/ml, respectively (P < 0.01, all comparisons) and mean half-lives were 4.5, 4.3, and 6.5 h, respectively (P < 0.05, C versus A and B). Mean steady-state areas under the concentration-time curve were 14.1, 21.1, and 48.1 micrograms/h/ml for regimens A, B, and C, respectively (P < 0.05, all comparisons). SBTs were determined at different times postdose for three isolates each of Streptococcus pneumoniae, Staphylococcus aureus, Escherichia coli, Enterobacter cloacae, and Pseudomonas aeruginosa. Mean steady-state peak SBTs for regimens A, B, and C, respectively, were as follows: S. pneumoniae, < 1:2, 1:8, 1:8, S. aureus, 1:16, 1:16, 1:16; E. coli, 1: > or = 128, 1: > or = 128, 1:64; E. cloacae, 1: > or = 128, 1: > or = 128, 1:64; P. aeruginosa, 1:8, 1:8, 1:2. These differences in SBTs within each genus were statistically significant. The majority of predicted SBTs were within one dilution of measured SBTs. Areas under the serum bactericidal time curves for E. coli, E. cloacae, and P. aeruginosa were significantly higher for ciprofloxacin; areas under the serum bactericidal time curves for S. pneumoniae and S. aureus were significantly greater for ofloxacin. Ofloxacin achieved higher concentrations in serum than ciprofloxacin, but differences in in vitro activity were a more important determinant of SBTs.

Serum vitamin K concentration in pediatric patients receiving total parenteral nutrition

The only multivitamin preparation for total parenteral nutrition currently available in the United States that contains vitamin K is the pediatric formulation MVI-Pediatric. The recommended dose provides 200 micrograms of vitamin K1 per day to term infants and children up to 11 years old. This dose is well above the recommended dietary allowance of approximately 1 microgram/kg per day, but the losses of vitamin K during administration are unknown. We evaluated the stability of vitamin K1 in a standard total parenteral nutrition infusion and found that an average 72.7 +/- 4.9% of the original vitamin K1 was present after 24 hours. By using high-performance liquid chromatography with electrochemical reduction and fluorescence detection, we obtained the serum vitamin K1 concentrations in 11 pediatric patients receiving total parenteral nutrition with MVI-Pediatric (Rorer Pharmaceuticals, Fort Washington, PA) supplementation and in control children. The serum vitamin K1 concentration (19.3 +/- 12.2 ng/mL) in patients receiving MVI-Pediatric is significantly higher than that in control children 1.9 +/- 1.5 ng/mL (p < .001). Current practice results in excessive levels of vitamin K in pediatric patients.

Microscopic air embolism during cerebral angiography and strategies for its avoidance

Cerebral angiography is associated with a risk of neurological complications and air embolism may contribute towards this risk. To test this hypothesis, transcranial doppler ultrasonography was used to monitor the presence of air emboli in the middle cerebral arteries of 7 patients undergoing cerebral angiography. Doppler signals consistent with numerous air emboli were noted during each injection of radiographic contrast. This phenomenon was studied further in sheep. Radiographic contrast medium was injected into the carotid artery while a major carotid branch was insonated transorbitally. Embolic signals similar to those seen in patients were noted. Air was introduced at two points. First, at the time of drawing up the contrast into the syringe, especially with more viscous media. Standing the media before injection resulted in a highly significant reduction of air embolism, reducing the total mean duration of emboli from 1.32 (SD 0.60) s after immediate injection to 0.04 (0.05) s after ten minutes standing for iohexol 340 mg/mL (p < 0.001). Second, air was introduced at the time of injection, possibly by the formation of cavitation bubbles under pressure. This occurred most prominently with the less viscous contrast media and with saline, and was significantly reduced by slow injection (mean duration of emboli for saline 2.85 [2.43] s with fast injection compared with 0.32 [0.37] s with slow injection, p = 0.004). Air embolism may contribute towards neurological dysfunction after angiography. Measures should be taken to reduce this by allowing contrast media to stand prior to injection, and by flushing catheters with saline injected slowly.

Endomyocardial biopsy: advantages of adding a posterior bend to the bioptome

A modification of the distal end of a flexible bioptome used for endomyocardial biopsy is described which facilitates the approach to the interventricular septum. Contact with the right ventricular free wall is avoided.

The role of platelets, thrombin and hyperplasia in restenosis after coronary angioplasty

Coronary angioplasty has become a successful and widely used treatment for patients with coronary artery disease since its first clinical application in 1977. The primary success rate has improved despite the increase in procedure and case complexity. However, acute reocclusion and late restenosis, which constitute the most important problems after successful angioplasty, continue to occur in about 5% and 35% of patients within 3 to 6 months, respectively. Angioscopic and pathologic observations have suggested that a multifactorial pathophysiologic process accounts for acute reocclusion, involving marked thrombosis, intimal dissection, medial and subintimal hemorrhage, vascular recoil and vasocontriction. In contrast, chronic restenosis involves the development of fibrocellular intimal hyperplasia within a milieu created by vascular injury, platelet activation, thrombin generation and the release of mitogens. Although current pharmacologic approaches, which involve antithrombotic and anticoagulant therapy, have been largely ineffective in eliminating acute reocclusion and chronic restenosis, recent advances in the research in thrombosis, platelet receptors and smooth muscle growth regulation have allowed new therapeutic options to be tested in the experimental setting, with subsequent potential clinical applications in patients.

Spontaneous post-anesthetic tremor does not resemble thermoregulatory shivering

Spontaneous post-anesthetic tremor that resembles shivering is common during recovery from anesthesia. Risks to postoperative patients include an increase in metabolic rate of up to 400%, hypoxemia, wound dehiscence, dental damage, and disruption of delicate surgical repairs. The etiology of spontaneous post-anesthetic tremor is most commonly attributed to normal thermoregulatory shivering in response to intraoperative hypothermia. However, the mechanism of this tremor remains unknown, hampering prevention and treatment. The present study was designed to determine whether mechanisms other than thermoregulation contribute to the tremor. The electromyograms (EMGs) of eight muscles were observed in nine women during recovery from isoflurane anesthesia. Signals from each muscle were compared to those of pathologic clonus induced by plantar flexion in unanesthetized patients with spinal cord transections and to those of cold-induced shivering in normal, unanesthetized subjects. Two distinct EMG patterns were identified: 1) regular, bursting signals of 5-7 Hz similar to those produced by pathologic clonus in patients with spinal cord transections; and 2) tonic, irregular signals of 5-15 Hz which had poorly defined bursts that did not demonstrate the synchronous 4-8-cycle/min waxing and waning pattern typical of normal shivering. EMG activity occurred most often at expired isoflurane concentrations of 0.1-0.19%, and was not related to rectal temperature. During the later part of recovery when isoflurane concentrations were less than or equal to 0.1%, hypothermic patients frequently demonstrated no clinical or EMG evidence of muscular activity.(ABSTRACT TRUNCATED AT 250 WORDS)

Human studies concerning thermal-induced shivering, postoperative "shivering," and cold-induced vasodilation

Human reaction to cold stress and hypothermia involves shivering. Another form of overt shaking, postoperative shivering, has been attributed as a thermoregulatory response to postoperative hypothermia. Analysis of the normal human shivering pattern showed a synchronized, slow amplitude modulation (six to eight cycles/min) over all muscles sampled. In addition, there was a frequency of 8 to 10 Hz associated with each low-frequency amplitude modulation. EMG signals from postoperative patients revealed none of the major patterns seen in thermal-induced shivering. Cold-induced vasodilation also was studied and found to occur simultaneously in all cold-stressed fingers regardless of size or innervation. Thermal shivering and cold-induced vasodilation are considered to be manifestations of central neural oscillators.

Biochemical and genetic analysis of variant mouse hepatoma cells defective in the induction of benzo(a)pyrene-metabolizing enzyme activity

We have analyzed wild type mouse hepatoma (Hepa 1c1c7) cells and variant cells which are defective in the induction of benzo(a)pyrene-metabolizing enzyme activity. One type of variant has no detectable basal or inducible aryl hydrocarbon hydroxylase activity. This class contains apparently normal cytosolic receptors for 2,3,7,8-tetrachlorodibenzo-p-dioxin, but is unable to translocate the inducer-receptor complex to the nucleus. The second type of variant has low levels of basal and inducible aryl hydrocarbon hydroxylase activity. This class contains cytosolic receptors which are decreased either in their number or in their ability to bind 2,3,7,8-tetrachlorodibenzo-p-dioxin; translocation of the inducer-receptor complex to the nucleus is apparently normal. Cell fusions indicate that both variant phenotypes are recessive with respect to wild type. Complementation analyses indicate that the defects are located on different genes.

[Lactic acidosis and intensive care. 16 cases (author's transl)]

Sixteen cases of lactic acidosis are reported: 7 phenformin treated diabetes, 5 cardiovascular diseases (2 myocardial infractions, 2 pulmonary embolisms, 1 heart failure). In 2 patients no etiology was found. Concomittant renal failure or liver diseases were found in respectively 9 and 4 cases. Patients presented the usual criteria of lactic acidosis: clinical, polypnea, severe hypotension (9/16), peripheral symptoms of shock (12/16), hypothermia (9/16), abdominal pain (9/16): biologically, acidosis (pH = 6,99 +/- 0,01, HCO3- = 5,9 +/- 1,5 mmol), hyperlactatemia (14,1 +/- 3,6 mmol/l) with hig lactate/pyruvate ratio (105 +/- 73), and anion gap (24,3 +/- 4,2 mmol/l). Sodium bicarbonate infusion was performed in all cases (2,5 to 42 mmol/kg). Few cases required volhemic expansion or furosemid induced diuresis. One patient was treated with extrarenal dialysis. 13 patients were alkalinised with less than 185% of estimated deficit measured from alkalin reserve: 12 died. 3 patients received 185% more than this deficit, associated with furosemid (1,8 to 12,5 mg/kg): only one patient died ten days after by casual disease, with lactatemia of 3,2 mmol/l. In spite of the small number of patients, these findings suggest that an early and massive alkalinisation, with large doses of furosemid, can improve the severe lactic acidosis prognosis.