Union of the European Phoniatricians' position statement on the exit strategy of phoniatric and laryngological services: staying safe and getting back to normal after the peak of coronavirus disease 2019 (issued on 25th May 2020)

BACKGROUND

The following position statement from the Union of the European Phoniatricians, updated on 25th May 2020 (superseding the previous statement issued on 21st April 2020), contains a series of recommendations for phoniatricians and ENT surgeons who provide and/or run voice, swallowing, speech and language, or paediatric audiology services.

OBJECTIVES

This material specifically aims to inform clinical practices in countries where clinics and operating theatres are reopening for elective work. It endeavours to present a current European view in relation to common procedures, many of which fall under the aegis of aerosol generating procedures.

CONCLUSION

As evidence continues to build, some of the recommended practices will undoubtedly evolve, but it is hoped that the updated position statement will offer clinicians precepts on safe clinical practice.

Evaluation of drug permeability calculation based on luminal disappearance and plasma appearance in the rat single-pass intestinal perfusion model

The rat single-pass intestinal perfusion (SPIP) model is commonly used to investigate gastrointestinal physiology and membrane drug transport. The SPIP model can be used with the intestinal segment inside or outside the abdomen. The rats can also be treated with parecoxib, a selective cycloxygenase-2 inhibitor that has been shown to affect some intestinal functions following abdominal surgery, such as motility, epithelial permeability, fluid flux and ion transport. However, the impact of extra-abdominal placement of the intestinal segment in combination with parecoxib on intestinal drug transport has not been investigated. There is also uncertainty how well intestinal permeability determinations based on luminal drug disappearance and plasma appearance correlate in the rat SPIP model. The main objective of this rat in vivo study was to investigate the effect of intra- vs. extra-abdominal SPIP, with and without, pretreatment with parecoxib. The effect was evaluated by determining the difference in blood-to-lumen ⁵¹Cr-EDTA clearance, lumen-to-blood permeability of a cassette-dose of four model compounds (atenolol, enalaprilat, ketoprofen, and metoprolol), and water flux. The second objective was to compare the jejunal permeability values of the model drugs when determined based on luminal disappearance or plasma appearance. The study showed that the placement of the perfused jejunal segment, or the treatment with parecoxib, had minimal effects on membrane permeability and water flux. It was also shown that intestinal permeability of low permeability compounds should be determined on the basis of data from plasma appearance rather than luminal disappearance. If permeability is calculated on the basis of luminal disappearance, it should preferably include negative values to increase the accuracy in the determinations.

Time-dependent effects on small intestinal transport by absorption-modifying excipients

The relevance of the rat single-pass intestinal perfusion model for investigating in vivo time-dependent effects of absorption-modifying excipients (AMEs) is not fully established. Therefore, the dynamic effect and recovery of the intestinal mucosa was evaluated based on the lumen-to-blood flux (J_abs) of six model compounds, and the blood-to-lumen clearance of ⁵¹Cr-EDTA (CL_Cr), during and after 15- and 60-min mucosal exposure of the AMEs, sodium dodecyl sulfate (SDS) and chitosan, in separate experiments. The contribution of enteric neurons on the effect of SDS and chitosan was also evaluated by luminal coadministration of the nicotinic receptor antagonist, mecamylamine. The increases in J_abs and CL_Cr (maximum and total) during the perfusion experiments were dependent on exposure time (15 and 60 min), and the concentration of SDS, but not chitosan. The increases in J_abs and CL_Cr following the 15-min intestinal exposure of both SDS and chitosan were greater than those reported from an in vivo rat intraintestinal bolus model. However, the effect in the bolus model could be predicted from the increase of J_abs at the end of the 15-min exposure period, where a six-fold increase in J_abs was required for a corresponding effect in the in vivo bolus model. This illustrates that a rapid and robust effect of the AME is crucial to increase the in vivo intestinal absorption rate before the yet unabsorbed drug in lumen has been transported distally in the intestine. Further, the recovery of the intestinal mucosa was complete following 15-min exposures of SDS and chitosan, but it only recovered 50% after the 60-min intestinal exposures. Our study also showed that the luminal exposure of AMEs affected the absorptive model drug transport more than the excretion of ⁵¹Cr-EDTA, as J_abs for the drugs was more sensitive than CL_Cr at detecting dynamic mucosal AME effects, such as response rate and recovery. Finally, there appears to be no nicotinergic neural contribution to the absorption-enhancing effect of SDS and chitosan, as luminal administration of 0.1 mM mecamylamine had no effect.

The effects of three absorption-modifying critical excipients on the in vivo intestinal absorption of six model compounds in rats and dogs

Pharmaceutical excipients that may affect gastrointestinal (GI) drug absorption are called critical pharmaceutical excipients, or absorption-modifying excipients (AMEs) if they act by altering the integrity of the intestinal epithelial cell membrane. Some of these excipients increase intestinal permeability, and subsequently the absorption and bioavailability of the drug. This could have implications for both the assessment of bioequivalence and the efficacy of the absorption-enhancing drug delivery system. The absorption-enhancing effects of AMEs with different mechanisms (chitosan, sodium caprate, sodium dodecyl sulfate (SDS)) have previously been evaluated in the rat single-pass intestinal perfusion (SPIP) model. However, it remains unclear whether these SPIP data are predictive in a more in vivo like model. The same excipients were in this study evaluated in rat and dog intraintestinal bolus models. SDS and chitosan did exert an absorption-enhancing effect in both bolus models, but the effect was substantially lower than those observed in the rat SPIP model. This illustrates the complexity of the AME effects, and indicates that additional GI physiological factors need to be considered in their evaluation. We therefore recommend that AME evaluations obtained in transit-independent, preclinical permeability models (e.g. Ussing, SPIP) should be verified in animal models better able to predict in vivo relevant GI effects, at multiple excipient concentrations.

Computational fluid dynamics (CFD) studies of a miniaturized dissolution system

Dissolution testing is an important tool that has applications ranging from fundamental studies of drug-release mechanisms to quality control of the final product. The rate of release of the drug from the delivery system is known to be affected by hydrodynamics. In this study we used computational fluid dynamics to simulate and investigate the hydrodynamics in a novel miniaturized dissolution method for parenteral formulations. The dissolution method is based on a rotating disc system and uses a rotating sample reservoir which is separated from the remaining dissolution medium by a nylon screen. Sample reservoirs of two sizes were investigated (SR6 and SR8) and the hydrodynamic studies were performed at rotation rates of 100, 200 and 400rpm. The overall fluid flow was similar for all investigated cases, with a lateral upward spiraling motion and central downward motion in the form of a vortex to and through the screen. The simulations indicated that the exchange of dissolution medium between the sample reservoir and the remaining release medium was rapid for typical screens, for which almost complete mixing would be expected to occur within less than one minute at 400rpm. The local hydrodynamic conditions in the sample reservoirs depended on their size; SR8 appeared to be relatively more affected than SR6 by the resistance to liquid flow resulting from the screen.

A miniaturized in vitro release method for investigating drug-release mechanisms

We have evaluated a miniaturized in vitro method, based on the μDISS Profiler™ technique that enables on-line monitoring of drug release from a 21 μl sample with 10 ml of release medium. Four model drugs in eight clinically used formulations, including both solid and non-solid drug delivery systems, were investigated. The acquired data were compared with historical in vitro release data from the same formulations. Use of the Weibull function to describe the in vitro drug-release profiles allowed discrimination between the selected formulations with respect to the drug-release mechanisms. Comparison of the release data from the same formulation in different in vitro set-ups showed that the methodology used can affect the mechanism of in vitro release. We also evaluated the ability of the in vitro methods to predict in vivo activity by comparing simulated plasma concentration-time profiles acquired from the application of the biopharmaceutical software GI-Sim to the in vitro observations. In summary, the simulations based on the miniaturized-method release data predicted the plasma profiles as well as or more accurately than simulations based on the historical release data in 71% of the cases and this miniaturized in vitro method appears to be applicable for both solid and non-solid formulations.

Inhibition of different strains of enteropathogens in a lactic-fermenting cereal gruel

Twenty-eight strains of enteropathogens, including Campylobacter, Salmonella, Shigella, enterotoxigenic Escherichica coli (ETEC), Staphylococcus and Bacillus were added to cereal gruels prepared from low-tannin sorghum and inoculated with a lactic acid starter culture. Campylobacter strains were not detectable after 6 h, and Salmonella, Shigella and Staphylococcus strains not after 12 h. No viable cells of Bacillus strains were detected after 16 h of fermentation and the ETEC strains were completely inhibited after 24 h. No strain variability was observed within the different genera. In control gruels (no starter culture added), all the enteropathogens increased in number during incubation at 32°C except for the Campylobacter strains which decreased after 12 h of incubation.

Interleukin-6 levels in relation to psychosocial factors: studies on serum, saliva, and in vitro production by blood mononuclear cells

Psychosocial factors and interleukin-6 (IL-6) levels are both related to risk of morbidity and mortality. The aim of this study was to investigate how a broad range of psychosocial factors related to levels of IL-6 in different media. Fifty-nine men and women aged 30-65 were recruited from a larger study and selected to cover a broad range of psychosocial status. IL-6 levels were analyzed in serum, in saliva collected at home at three different time points during a day, and in the supernatant of cell cultures stimulated in vitro with lipopolysaccharide. After adjustments for age, gender, self-reported health problems, and lifestyle factors, IL-6-levels in serum were negatively correlated with coping and self-esteem, and positively correlated with cynicism, hostile affect, hopelessness, depression, and vital exhaustion. In saliva samples, at all time points, IL-6 levels were positively correlated to cynicism, and IL-6 levels 30 min after awakening were also positively correlated with hopelessness, depression, and vital exhaustion. After adjustment for age and gender, cynicism, depression, and vital exhaustion were negatively correlated to IL-6 levels in the supernatant of cell cultures stimulated in vitro with lipopolysaccharide, but this effect was lost after control for self-reported health problems and lifestyle factors. In conclusion, we found that IL-6 levels in serum and saliva were negatively related to psychosocial resources and positively related to psychosocial risk factors. These data strengthen the argument that IL-6 is involved in mediating the risk for disease development that has been associated with psychosocial factors.

Enteropathogenic bacteria in faecal swabs of young children fed on lactic acid-fermented cereal gruels

The influence of consumption of a lactic acid-fermented cereal gruel togwa with pH < or = 4 on the presence of faecal enteric bacteria such as campylobacter, enterohaemorrhagic Escherichia coli (EHEC:O157), enterotoxigenic Escherichia coli (ETEC), salmonella and shigella was evaluated. Under 5 years old healthy children listed in an ascending order of age were alternatively assigned and given either a lactic-acid fermented cereal gruel togwa (test diet) or an unfermented cereal gruel uji (control diet) once a day for 13 consecutive days. The presence of the enteropathogens was examined in rectal swabs collected from the children at baseline (before feeding session started), on days 7 and 13, and additionally 14 days (follow-up day) after the feeding session had stopped. The swabs were cultured on to different optimal media for respective enteropathogen and confirmed by standard microbiological and serological methods. Campylobacter spp. dominated among the enteropathogens (62% out of total) followed by Salmonella spp., ETEC and Shigella spp. Children with isolated enteropathogens in the togwa group was significantly reduced (P < 0.001) from 27.6% at baseline to 7.8, 8.2 and 12.7% on days 7, 13 and follow-up day, respectively. The effect was more pronounced in those children taking togwa > 6 times during the study period. In the control group, there was a slight decrease from 16.7% at baseline to 11.4% on day 7 and 8.1% on day 13. On the follow-up day, enteropathogens were found in 22.6% of the children, which was significantly higher than in those children taking togwa > 6 times. We conclude, that regular consumption of togwa with pH < or = 4, once a day, three times a week may help to control intestinal colonization with potential diarrhoea-causing pathogens in young children.

Rapid emergence of high-level resistance to quinolones in Campylobacter jejuni associated with mutational changes in gyrA and parC

Quinolone resistance in clinical isolates of Campylobacter jejuni in Sweden increased more than 20-fold at the beginning of the 1990s. Resistance to 125 microgram of ciprofloxacin per ml in clinical isolates was associated with chromosomal mutations in C. jejuni leading to a Thr-86-Ile substitution in the gyrA product and a Arg-139-Gln substitution in the parC product.

Norfloxacin resistance in Campylobacter jejuni and Campylobacter coli isolates from Swedish patients

This study focused on the frequency of Campylobacter jejuni and Campylobacter coli strains resistant to norfloxacin. Included were 1659 consecutive stool specimens isolated between 1992 and 1995, from as many Swedish patients with diarrhoea. The patients were divided with regard to place of infection and age. All strains were tested for susceptibility to norfloxacin by means of disc diffusion test on blood-agar plates. Norfloxacin-resistant strains (n = 310) were furthermore tested for resistance to doxycycline and erythromycin. The Etest was used for determination of MIC values of doxycyclin, erythromycin and norfloxacin of 81 of the strains. C. jejuni and C. coli isolations resistant to norfloxacin were significantly more frequent among patients infected abroad, especially in Spain and Thailand, compared with those infected in Sweden, adults more often than children. The number of resistant strains showed a yearly increase, and the difference between children and adults was equalized in 1995. The MIC50 and MIC90 values for doxycycline and erythromycin have increased markedly through the 4 years studied. This study shows that norfloxacin, because of increased resistance, may have limited utility for treatment of gastrointestinal infections caused by C. jejuni and C. coli.

The serotype distribution of Campylobacter jejuni and C. coli isolated from patients with diarrhoea and controls at Tikur Anbassa Hospital, Addis Ababa, Ethiopia

Sixty-eight isolates of Campylobacter jejuni and C. coli isolated from patients with diarrhoea (n = 630) and controls (n = 220) at Tikur Anbassa Hospital, Addis Ababa, Ethiopia were serotyped on the basis of the heat-labile (HL) and the heat-stable (HS) antigens, by using 16 and 34 antisera, respectively, for the two methods. With the antisera against heat labile antigens, 89.3% of the C. jejuni and 75% of the C. coli were typable. The HL serotypes 1, 2, 3, 4, 5, 6 and 7 were the most common among the C. jejuni while HL serotypes 1 and 2 were dominant among the C. coli isolates. These serotypes accounted for 63.2% of all isolates. For the heat-stable antigens, 60% of the C. jejuni and 83.3% of the C. coli isolates were typable. The HS serotypes 1, 3, 8, 26 and 34 were most common among the C. jejuni, while serotypes 3 and 8 were dominant among C. coli isolates. This study shows that the most common HL and HS antigens among campylobacter isolates from Ethiopia correspond to the most frequent antigenic types from other parts of the world. A limited number of antisera were sufficient to identify the majority of the isolates.

DNA fingerprinting and serotyping of Campylobacter jejuni isolates from epidemic outbreaks

The aim of the present investigation was to compare DNA fingerprinting and serotyping (heat-stabile and heat-labile antigens) of isolates from epidemic outbreaks as well as of solitary isolates. Campylobacter jejuni isolates from two epidemic outbreaks in Sweden, one milkborne (35 isolates) and one waterborne (17 isolates), and one waterborne outbreak in Norway (11 isolates), as well as 30 solitary isolates from Swedish patients with gastroenteritis, were analyzed. A total of 93 isolates were analyzed. In the waterborne outbreak in Norway, only one serotype with one DNA pattern was found. In the milkborne outbreak in Sweden, two serotypes (HS2:HL4 and HSNT:HL4) with two different DNA patterns were found. The isolates from the waterborne outbreak in Sweden were different serotypes. For two isolates of the same serotype, different DNA patterns were seen. This was also recorded for isolates from solitary cases. It was concluded that serotyping is a useful tool in most epidemiological situations but sometimes lacks sufficient discriminatory power. DNA fingerprinting can add valuable epidemiological information to that supplied by serotyping and can in some situations provide sufficient epidemiological information when used alone.

Campylobacter jejuni/coli and enterotoxigenic Escherichia coli (ETEC) in faeces from children and adults in Tanzania

The occurrence of Campylobacter and enterotoxigenic E. coli (ETEC) was studied in faecal samples from Tanzanian children (< 5 years of age), adolescents and adults (only Campylobacter) with and without diarrhoea. The Campylobacter strains isolated were tested for subspecies, enterotoxigenicity and serotype. Out of 394 children with diarrhoea 18% were infected with Campylobacter and 20% with ETEC. In 278 samples tested for Campylobacter and 136 tested for ETEC from asymptomatic children the corresponding numbers were 12 and 5%, respectively. In children < 18 months with diarrhoea Campylobacter was noted in 22% and ETEC in 18%, whereas the figures were 11 and 4% respectively in asymptomatic children. In the age group 18 months to 5 years Campylobacter was demonstrated in 2% of the children with diarrhoea and 27% had ETEC, while the figures were 15 and 8% for asymptomatic children. Among adults the prevalence of Campylobacter-positive samples was 1% both for symptomatic and asymptomatic individuals. There were no seasonal differences in the prevalences of both Campylobacter and ETEC either in the symptomatic or the asymptomatic group. Campylobacter jejuni was the dominating Campylobacter species among both symptomatic and asymptomatic individuals. C. jejuni strains from patients with diarrhoea were significantly more often enterotoxigenic than were C. coli strains. The serotype pattern regarding Campylobacter was in general similar for symptomatic and asymptomatic individuals. We conclude that Campylobacter and ETEC are common causes of bacterial diarrhoea in Tanzanian children, and that Campylobacter infections are more important in children younger than 18 months, than in older ones.

Frequency and enterotoxigenicity of Campylobacter jejuni and C. coli in domestic animals in Pakistan as compared to Sweden

Domestic and wild animals have been considered to be the most common reservoirs of Campylobacter for human infections. This study has been conducted to establish the frequency and enterotoxigenicity of C. jejuni and C. coli in the stools of domestic animals in a developing versus a developed country. Faecal samples of 300 chickens and laying hens, 102 horses, 180 cows, 92 goats and sheep were collected from Pakistan and Sweden. The hippurate hydrolysis test and CHO-cell test were performed for species differentiation and enterotoxigenicity determination respectively. The pattern and sequence of frequency distribution of Campylobacter in animals in Pakistan and Sweden were similar, the main difference being a significantly higher frequency in Pakistani samples. C. jejuni was the dominant species from both countries and Pakistani strains were more enterotoxigenic than Swedish strains. We conclude that the spread of Campylobacter infection in developing countries originates from different sources in the neighbourhood, for example animals, and unless hygienic conditions improve no change can be expected.

Antimicrobial susceptibilities of Campylobacter jejuni and Campylobacter coli isolated in Sweden: a 10-year follow-up report

Resistance to erythromycin and doxycycline and more recently to fluoroquinolones has been reported to occur in Campylobacter spp. both in vitro and in patients treated with these antibiotics. The frequency of resistance to 14 antimicrobial agents in Campylobacter jejuni and Campylobacter coli isolated from patients infected in Sweden or abroad is described. For some agents, a comparison of susceptibility in strains of Campylobacter spp. isolated in 1978 with those isolated in 1988 is made. No general increase in in vitro resistance to antibiotics commonly used for the treatment of human gastroenteritis caused by C. jejuni or C. coli has occurred during the last 10 years in Sweden, which might be a consequence of strict antibiotic control. The numbers of strains from 1988 to 1989 resistant to ciprofloxacin and to norfloxacin included in this study (0.7 and 1.4%, respectively) are still fewer than those that were resistant to erythromycin (7.3%) or doxycycline (12.4%). There is, however, since 1989 to 1990 an indication of increasing resistance to these antibiotics.

Rapid emergence of quinolone resistance in Campylobacter jejuni in patients treated with norfloxacin

15/60 subjects from one center, who all took part in a multicenter double-blind, placebo-controlled study to evaluate the effect of norfloxacin on acute enteritis, had norfloxacin sensitive strains of Campylobacter jejuni in pre-study stool specimens. Eight of the 15 subjects received active drug. In 3 of these 8, high-level quinolone resistant Campylobacter strains of the same serotype as in pre-treatment samples were isolated 4-90 days after the initiation of treatment.

Adherence, enterotoxigenicity, invasiveness and serogroups in Campylobacter jejuni and Campylobacter coli strains from adult humans with acute enterocolitis

Two hundred Campylobacter jejuni and Campylobacter coli strains from the same number of adult Swedish patients with acute enterocolitis were tested regarding adherence to and invasiveness in HEp-2 cells and for enterotoxigenicity by the CHO-cell assay. The serogroup characteristics, heat-stable and heat-labile, for each strain were also investigated. Eighty-four percent of the strains were classified as C. jejuni and 16 percent as C. coli. All of the strains were adherent to HEp-2 cells, 39% were invasive and 31.5% enterotoxigenic. We found significantly more invasive strains in the non-enterotoxigenic group than in the enterotoxigenic one. There would seem to be no correlation between enterotoxigenicity or invasiveness and serogroup. The results of this study suggest the existence of multiple mechanisms for C. jejuni- and C. coli-induced diarrhoea and that the mechanisms may differ from one strain to another.

Plasmids and serogroups in Campylobacter jejuni

For epidemiological purposes identification of Campylobacter strains is usually based on surface antigen characteristics. Two different systems, one for heat-stable (HS) and one for heat-labile (HL) antigen have dominated. In earlier studies we found a great variability in the two antigen systems. The aim of the present investigation was to analyse the frequency of plasmids in Campylobacter strains in the light of their possible use as an epidemiological tool as well as the relation between the presence of plasmids and surface antigens (HS and HL). Two hundred and forty-two strains from the same number of patients with diarrhea were analysed. In 70 (28.9%) plasmid(s) were found, in general one or two. Most of the plasmids were found in the molecular weight interval between 21-40 Md. There was no relation between the presence or size of plasmids and serogroup. We conclude that plasmid determination can be used as a complement to serotyping in epidemiological studies.

Enterotoxin production and serogroups of Campylobacter jejuni and Campylobacter coli from patients with diarrhea and from healthy laying hens

Enterotoxin production, a possible virulence factor, was determined in Campylobacter jejuni and Campylobacter coli by two different techniques, the CHO cell test and the GM1 enzyme-linked immunosorbent assay. The frequency of enterotoxigenic Campylobacter strains was 32% in strains from both humans with acute enteritis and healthy laying hens, as measured by the CHO cell test. The CHO cell test was significantly more sensitive than the GM1 enzyme-linked immunosorbent assay in the detection of enterotoxigenic strains. Enterotoxin production was compared with the presence of heat-stable and heat-labile antigens. There was no significant correlation between enterotoxin production and serogroups for C. jejuni or C. coli. The difference in enterotoxigenicity between C. jejuni (34.1%) and C. coli (21.9%) was not significant.

Serotyping studies of Campylobacter from naturally colonized chickens

Campylobacter jejuni/coli strains from 164 chickens were serotyped by the methods previously described by Penner et al. and Lior et al. The chickens were sampled during breeding from hatching to the age of 42 weeks. The birds were housed, in two separate groups, under different environmental conditions, (for comparison of the effect of hygienic precautions on the transmission of the bacteria during breeding). In the group where the hygienic conditions could be controlled to a greater extent, the chickens became colonized later in the breeding chain and with only one single campylobacter strain. Once campylobacter appeared in the group housed at the breeding farm, the birds were colonized with heterogenous antigenic strains. All birds in this group were colonized with more than one strain. By identifying campylobacter strains from chickens during breeding, it was shown that the hygienic conditions are very important for the production of chickens free from campylobacter, or for minimizing the number of colonizing strains.

Campylobacter strains from Swedish patients with diarrhoea. Distribution of serotypes over a five year period

Serotyping, HS antigen and HL antigen, was performed on 105 Campylobacter jejuni/coli isolates from the same number of consequtive patients seeking medical attention for diarrhoea. The results were compared to a similar study performed five years earlier. It was found that there were only minor differences in frequency of the serotypes commonly isolated during the two different periods.

Campylobacter jejuni isolations from Mexican and Swedish patients, with repeated symptomatic and/or asymptomatic diarrhoea episodes

The presence of different Campylobacter jejuni serotypes in Swedish patients with diarrhoea and in Mexican patients with or without diarrhoea was investigated with special reference to repeated isolations during the course of infection and to symptomatic and asymptomatic episodes. The study included 136 C. jejuni isolates from 62 Mexican children and 173 isolates from 68 Swedish patients. The bacteria were serotyped for heat-stable (HS) and heat-labile (HL) antigen. Swedish patients, all with symptoms, were in general only infected with one serotype and were rarely reinfected. Mexican patients on the other hand were in general infected with mixed serotypes and frequently reinfected without symptoms with new, different serotypes, a finding which is in concordance with a theory of an induced immunity to surface antigens.

The serotype distribution of Campylobacter in patients with diarrhoea in Kuwait

Fifty one strains of Campylobacter jejuni/coli isolated from patients with diarrhoea, at the Amiri Hospital, Hawally, Kuwait were classified on the basis of the heatstable-HS-antigens and the heat-labile-HL-antigens, by using 20 and 23 hyperimmune antisera for the two methods, respectively. The ages of the patient ranged from 3 months to 60 years, and 72.6% of the strains were from children less than 4 years. With the number of antisera used 78.4% of the HS antigens and 96.1% of the HL antigens could be identified. About half of the strains had one of five HS antigens (4, 8, 13, 5 or 25) and 70.5% of the strains had one of five HL antigens (1, 36, 2, 6, or 21). The study shows that the most common HS and HL antigens among Campylobacter strains from Kuwait also are the most frequent antigens of strains from other parts of the world. A limited number of antisera are sufficient to identify the majority of the strains.

Comparison of different procedures, transport media, and enrichment media for isolation of Campylobacter species from healthy laying hens and humans with diarrhea

A comparison was made with some of the available transport and enrichment media for the isolation of Campylobacter species. The merits of duplicate versus single sampling were also investigated. Fecal samples from 721 healthy laying hens and 328 patients with diarrhea were included in the study. The media compared were modified Stuart medium, Campythio-glycolate medium, semisolid motility test medium, and Campylobacter enrichment broth. The isolation rate of Campylobacter species was significantly increased by taking duplicate instead of single samples. The highest outcome was found when one of the two samples was an enrichment medium, such as semisolid motility test medium.

Glucose tolerance in hypertensive patients during treatment with the calcium antagonist, felodipine

1 Twelve non-diabetic hypertensive male patients insufficiently controlled by a diuretic were included in a double-blind, randomised study. In addition placebo or felodipine was given for 4 weeks followed by a 2 week wash-out period, after which the alternative treatment was given for another 4 weeks. At the end of each treatment period an oral glucose tolerance test (OGTT) was performed and blood pressure, plasma noradrenaline and felodipine levels were measured. 2 There was no change in either glucose, insulin or glucagon levels during the OGTT after felodipine compared with placebo. Blood pressure was significantly reduced during the dosage interval of felodipine (12 h). Plasma noradrenaline increased significantly after felodipine. Side effects were few. 3 In a separate open study 58 hypertensive patients were treated with felodipine in addition to a diuretic and a beta-adrenoceptor blocker for up to 1 year. There were no significant changes in fasting blood glucose levels during the study.

Antihypertensive effects and pharmacokinetics of felodipine combined with a beta-blocker and a diuretic

The antihypertensive effect of felodipine, a new calcium antagonist with dihydropyridine structure, was investigated in 25 patients with essential hypertension that was not controlled on standard triple therapy (a beta-blocker, a diuretic, and a vasodilator). After substituting the previous vasodilator with felodipine, blood pressure was reduced and remained well controlled during a 2 year follow-up period. After about 1 1/2 years of treatment, felodipine was compared double-blind with placebo in a subgroup of 10 patients while keeping the same beta-blocker and diuretic therapy. Compared with the placebo, felodipine lowered blood pressure during a 12 h interval, which supports a twice-daily dosage in clinical practice. Determination of the plasma concentrations of felodipine during steady-state conditions showed a mean elimination half-life of 23.4 +/- 11.1 h. During long-term therapy, tolerance was good, and felodipine seems to be a safe and efficient antihypertensive agent in combination with a beta-blocker and a diuretic in patients whose hypertension is not adequately controlled on standard triple therapy.

Comparison of antihypertensive effect and pharmacokinetics of conventional and extended release felodipine tablets in patients with arterial hypertension

In 2 separate double-blind, placebo-controlled, crossover studies, the antihypertensive effect and felodipine plasma concentrations were studied after 2 different formulations of felodipine. Both trials studied patients who had previously responded unsatisfactorily to conventional triple therapy (beta-adrenergic blocker, diuretic and vasodilator). Felodipine or corresponding placebo was added to the pre-existing beta-adrenergic blocker/diuretic combination. Both tablet formulations significantly lowered blood pressure. In patients taking plain felodipine tablets, 10mg bid for 10 days, the blood pressure reduction was evident for 12 hours but not 24 hours after each dose. At steady state, the maximal felodipine plasma concentration was 25.2 +/- 1.5 nmol/L and occurred 1.3 +/- 0.2 (range 1 to 3) hours after drug intake. When an extended release formulation of felodipine (20mg once every morning) was used, a more even plasma concentration curve was achieved. After 2 weeks' treatment, the maximal felodipine plasma concentration was 23.3 +/- 2.7 nmol/L and was reached 4.4 +/- 0.5 (range 3 to 7) hours after each dose. Systolic as well as diastolic blood pressure at steady state were reduced over 24 hours. No disturbing side effects were noted on either felodipine formulation. From these studies we conclude that oral felodipine lowers blood pressure in patients with moderate to severe hypertension when added to a beta-adrenergic blocker/diuretic combination. The extended release formulation given in a once-daily long term regimen produced a significant and equally satisfactorily controlled blood pressure reduction over 24 hours compared with the plain tablets but has the advantage of once-daily rather than twice-daily administration.

Treatment of essential hypertension with felodipine in combination with a diuretic

In a double-blind cross-over study, the effect on blood pressure (BP), heart rate (HR) and plasma noradrenaline concentration (pNA) of placebo or felodipine given in addition to hydrochlorothiazide was studied in 12 male patients with essential hypertension, not satisfactorily controlled with the diuretic alone. The first dose of felodipine decreased BP and increased HR for about 6 h. After 4 weeks of treatment with felodipine, BP was reduced for 24 h, whereas HR was only transiently increased. The elimination half-life of felodipine was about 23 h. The plasma noradrenaline concentration increased after felodipine and serum uric acid decreased. Side-effects were few and usually mild.

Campylobacter strains in Sweden. Serotyping and correlation to clinical symptoms

Campylobacter is one of the most common causes of diarrhoea in humans. Different typing systems have been put forward as aids to improved understanding of the epidemiology and clinical signs of the disease. In the present investigation we have adopted indirect haemagglutination for serotyping of heatstable (Penner) antigens and direct slideagglutination for heatlabile (Lior) antigens. All the strains from the patients (n = 277) seeking medical care for diarrhoea at the East Hospital, Göteborg, Sweden over 21 months were studied. With 19 antisera against heatstable antigens, 79.8% of the domestic strains were typable and 73.8% of the foreign strains. For the heatlabile antigens corresponding figures were 94.2% and 87.2%. There was a great variety of combinations of heatstable and heatlabile antigens on the strains. No marked relation between one antigen or antigen combination and clinical sign of disease was found. We conclude that serotyping is mainly useful for epidemiological studies. A limited number of antisera can be used for typing the majority of strains. If a choice is to be made, typing for heatlabile antigen seems simple and gives somewhat higher typability.

The occurrence of Campylobacter jejuni in fresh food and survival under different conditions

Campylobacter jejuni was an almost regular finding in chickens and in minced meat from pigs and cattle sold in ordinary food stores. The bacteria survived on the food at 4 degrees C for one week and frozen at -20 degrees C for three months. None of the strains tested survived heat treatment at 60 degrees C for longer than 15 min. C. jejuni is apparently a frequent guest in most kitchens. Correct food handling and heat treatment to at least 60 degrees C for 15 min should be enough to prevent infection.