Motivation and context of concurrent stimulant and opioid use among persons who use drugs in the rural United States: a multi-site qualitative inquiry

BACKGROUND

In recent years, stimulant use has increased among persons who use opioids in the rural U.S., leading to high rates of overdose and death. We sought to understand motivations and contexts for stimulant use among persons who use opioids in a large, geographically diverse sample of persons who use drugs (PWUD) in the rural settings.

METHODS

We conducted semi-structured individual interviews with PWUD at 8 U.S. sites spanning 10 states and 65 counties. Content areas included general substance use, injection drug use, changes in drug use, and harm reduction practices. We used an iterative open-coding process to comprehensively itemize and categorize content shared by participants related to concurrent use.

RESULTS

We interviewed 349 PWUD (64% male, mean age 36). Of those discussing current use of stimulants in the context of opioid use (n = 137, 39%), the stimulant most used was methamphetamine (78%) followed by cocaine/crack (26%). Motivations for co-use included: 1) change in drug markets and cost considerations; 2) recreational goals, e.g., seeking stronger effects after heightened opioid tolerance; 3) practical goals, such as a desire to balance or alleviate the effects of the other drug, including the use of stimulants to avoid/reverse opioid overdose, and/or control symptoms of opioid withdrawal; and 4) functional goals, such as being simultaneously energized and pain-free in order to remain productive for employment.

CONCLUSION

In a rural U.S. cohort of PWUD, use of both stimulants and opioids was highly prevalent. Reasons for dual use found in the rural context compared to urban studies included changes in drug availability, functional/productivity goals, and the use of methamphetamine to offset opioid overdose. Education efforts and harm reduction services and treatment, such as access to naloxone, fentanyl test strips, and accessible drug treatment for combined opioid and stimulant use, are urgently needed in the rural U.S. to reduce overdose and other adverse outcomes.

Neuraxial anesthesia for cardiac surgery: thoracic epidural and high spinal anesthesia - why is it different?

Anesthesiologists can offer much more then stable blood pressure and heart rate in the intraoperative period. By choosing appropriate anesthetic techniques they can tremendously influence perioperative stress. This may positively impact on the overall surgical outcome. One of the most intriguing aspects of neuraxial anesthesia is its ability to attenuate the stress response to surgery. At present there is no agreement on the clinical importance of such a response but there is substantial indirect evidence that it may play an important role in a patient's outcome. Neuraxial anesthesia supplemented by general anesthesia is justified and can be safely used in cardiac surgery. The authors of this expert opinion prefer spinal anesthesia to thoracic epidural anesthesia and have been using it routinely for the last 20 years without any neurological complications. The risk of spinal hematoma from a 27G spinal needle prior to full heparinization is unknown but in our opinion is remote. Both epidural and spinal techniques can and should have a place in modern cardiac anesthesia practice and should be further investigated.

Incidence and risk factors for microbial keratitis in Hong Kong: comparison with Europe and North America

PURPOSE

To establish the incidence, etiology and risk factors for microbial keratitis (MK) in Hong Kong.

METHODS

Two hundred and twenty-three new cases of presumed MK were recruited over a period of 17 months and comprehensive microbiologic studies performed. A nested case-control study was pursued for patients wearing contact lenses (CLW) to determine risk factors for MK with regards to types of CLW and hygiene practice.

RESULTS

Of the 223 patients recruited, 59 (26%) wore contact lenses. Corneal scrapes yielded positive cultures from 77 patients (35% overall, 56 non-CLW, 21 CLW). Two hundred and six CLW volunteers were recruited to participate in the case-control study, of whom 135 were matched with 45 CLW patients. The annual incidence of MK was 0.63 per 10,000 population and 3.4 per 10,000 CLW with rates for daily, extended and rigid lens wear of 3.09, 9.30 and 0.44 per 10,000 CLW respectively. Pseudomonas aeruginosa was the dominant bacterial pathogen. Six cases of Acanthamoeba keratitis occurred, five in CLW (incidence 0.33 per 10,000 CLW) and one following corneal abrasion. Non-CLW developed MK at a peak age of 73, which is 10 years younger than expected for Scotland and USA.

CONCLUSIONS

Previous ocular surface disease and trauma were the main risk factors for MK in Hong Kong. CLW appears at least as safe as that found in Scotland and the USA. Acanthamoeba keratitis was detected but with an incidence rate five times lower than Scotland. Factors predisposing hydrogel CLWs to MK, that were statistically significant, included overnight wear, poor hygiene and smoking.

Microbial keratitis in Hong Kong: relationship to climate, environment and contact-lens disinfection

Microbial keratitis has been studied in Hong Kong as a representative sub-tropical climate of south China. An 18-month investigation in 1997/98 of 223 cases of ulcerative keratitis (presumed microbial) was conducted in the 2 million population of Shatin and Kowloon at the Prince of Wales and Hong Kong Eye Hospitals respectively with comprehensive microbiology. A case-control study was pursued at the same time between 45 contact-lens wearers (CLW) developing microbial keratitis and 135 lens-wearing volunteers matched for age, sex, educational status and visual acuity. Home water supplies were sampled for Acanthamoeba. Previous ocular surface disease and trauma (preventable by wearing goggles for grinding) were common predisposing causes while cosmetic wear of contact lenses was responsible for 26% of cases overall. Pseudomonas aeruginosa was the commonest bacterium isolated, from both CLW and non-CLW, with infection being acquired within the community. These 28 pseudomonads remained fully sensitive to the third-generation cephalosporins, aminoglycosides and quinolone antibiotics, which is very encouraging. Fungi were isolated, predominantly Fusarium sp., but less commonly than expected. A fungal/bacterial ratio was obtained of 1/17, while in comparison, the expected ratio for a tropical climate ranges from 1/5 (Singapore) to 1/2 (South India). Acanthamoeba was the second commonest microbe isolated from keratitis of CLW. The domestic water environment of 8% of homes of both patients and controls wearing contact lenses was colonized with Acanthamoeba. Lack of hygiene, use of tap water for storing lenses, failure to air-dry lens-storage cases or use of one-step hydrogen peroxide disinfectant were identified as risk factors for keratitis in CLW. The study results commend use of multipurpose solutions by CLW in Hong Kong to achieve the lowest expected rates of infection.

Somatosensory evoked potential monitoring during cardiac surgery: an examination of brachial plexus dysfunction

OBJECTIVE

To observe the effects of the Favoloro and sternal retractors on the ulnar and median nerve somatosensory evoked potentials (SSEPs) and to identify any relationship with postoperative brachial plexus injury.

DESIGN

Prospective study.

SETTING

University hospital.

PARTICIPANTS

Twenty cardiac patients.

INTERVENTIONS

SSEPs were studied in patients undergoing cardiac surgery using normothermic cardiopulmonary bypass. Evoked potentials were obtained from bilateral median and ulnar nerves.

MEASUREMENTS

The incidence of nerve-specific SSEP changes and their temporal relationship to retractor usage were determined. The overall incidence of SSEP changes was 75%. There were no differences (p > 0.05) between the group showing changes (n = 15) and the group with no changes (n = 5) with respect to age, body surface area, weight, cross-clamp or cardiopulmonary bypass times. There also were no differences (p > 0.05) between the frequencies of left- and right-sided changes, or in nerve-specific SSEP changes. Seventy-four percent of SSEP changes correlated with retractor usage. No SSEP changes were associated with the Favoloro retractor. Significant SSEP depression, assessed by either percentage reduction in amplitude or persistent amplitude reduction, occurred in the absence of postoperative neurological deficits. There were no detected postoperative brachial plexus injuries.

CONCLUSIONS

SSEP changes correlate with the use of the sternal retractor but not the Favoloro retractor. It was not possible to replicate the results of previous investigators in predicting postoperative neurological deficits based on the SSEP changes, and therefore the routine application of SSEP as a monitor cannot be recommended on the basis on these data.

Acanthamoeba keratitis: first recorded case from a Palestinian patient with trachoma

Images

Successful medical therapy of Acanthamoeba keratitis with topical chlorhexidine and propamidine

INTRODUCTION

Following laboratory studies on new potential chemotherapy for Acanthamoeba keratitis, when chlorhexidine and propamidine provided an additive in vitro effect, a series of 12 patients with culture-proven Acanthamoeba keratitis from three UK centres was monitored during and after therapy.

METHODS

In all cases the clinical diagnosis was confirmed by amoebal culture. In some instances identification of the protozoa by direct microscopy of corneal tissue was possible. The medication was provided topically in drop form until the keratitis had resolved. In vitro sensitivity to chlorhexidine and propamidine was performed on all isolates and compared with sensitivity to a range of other drugs used for treatment of the infection.

RESULTS

In vitro drug testing confirmed that trophozoites and cysts of all 12 Acanthamoeba isolates were fully sensitive to chlorhexidine and propamidine. Therapy was satisfactory for controlling and eradicating the acanthamoebal infection in all patients. Three patients developed discrete stromal infiltration at the site of infection that resolved 1 week after commencing therapy, with or without use of steroids. Two patients developed a late inflammatory effect in the stromal scar at 6 months, which resolved with steroids. No clinical evidence of chlorhexidine toxicity was found in any patients.

CONCLUSIONS

The combination of topical chlorhexidine and propamidine was very effective for treating Acanthamoeba keratitis provided the drugs were continued for a sufficient period. No drug toxicity or resistance of Acanthamoeba isolates was observed in the 12 treated patients.

Possible environmental sources of Acanthamoeba spp in contact lens wearers

The water supply and dust samples from the home environment (bathrooms and kitchens) of 50 wearers of contact lenses (CLs) were cultured for the presence of free-living amoebae. CL cases, solutions, and water taps were cultured for bacteria, which amoebae require for growth. Acanthamoeba spp were isolated from water drawn from six bathroom cold water taps (tank supplied), five in the presence of limescale, and from one kitchen cold water tap (mains supplied). There was an association between the presence of limescale in water and direct culture for free-living amoebae, suggesting that scale provides a favourable microenvironment for amoebae. Acanthamoebae were also found in dust from around one washbasin. Nineteen of 50 CL cases, 12/122 CL care rinsing solutions, and 59/100 cold water taps yielded Gram negative bacteria which could be ingested by amoebae. It is concluded from this study that CLs should not be washed in first-drawn tank-fed cold water, especially if limescale is present, and that soft CLs should be rinsed in manufactured single-use, sterile solutions. Rigid CL and CL cases should only be washed with boiled tap water (preferably hot), or single-use sterile solutions, and stored dry to prevent multiplication of amoebae and Gram negative bacteria.

In vitro studies of water activity and bacterial growth inhibition of sucrose-polyethylene glycol 400-hydrogen peroxide and xylose-polyethylene glycol 400-hydrogen peroxide pastes used to treat infected wounds

Water activity and bacterial growth inhibition have been studied in formulations comprising either sucrose or xylose along with polyethylene glycol 400 and hydrogen peroxide. The pastes are chemically stable for 6 months if stored at 2 to 8 degrees C and have been shown to lower water activity to levels below those essential for bacterial growth and to be bactericidal even when diluted up to 50% with serum. Of the organisms tested, Staphylococcus aureus proved the least susceptible to the bactericidal effects of these pastes, and candida and gram-negative organisms proved the most susceptible. Pastes without hydrogen peroxide were less rapidly bactericidal than pastes with hydrogen peroxide, while polyethylene glycol 400 itself was found to have considerable antimicrobial activity. It is suggested that sucrose paste may be of benefit as a treatment for infected and malodorous wounds.

Microbial keratitis--the false negative

The investigation of presumed microbial keratitis includes microscopy and culture of corneal specimens obtained by scraping the infiltrated cornea. Routine microscopy fails to identify the infecting organism in about 15% of cases. We discuss the problems presented by 20 such eyes which required further investigation. We present a diagnostic algorithm aimed at reducing the delay in identifying the pathogen and increasing the rate of positive culture. This is important since unusual pathogens may require treatment with drugs other than the 'first line' broad spectrum combination of an aminoglycoside and a cephalosporin. The algorithm allows sequential restaining and reculturing of specimens for more thorough investigation. In addition to the use of special stains and culture conditions, it presents indications for further corneal scrapes and biopsies. Uncontrolled infection resulted in five perforations and penetrating keratoplasty was indicated in 11 cases. The visual outcome for these patients was poor with fewer than 30% achieving 6/12 acuity. The delay in diagnosis increases morbidity and this should be significantly reduced by adopting the algorithm we propose.

Northwick Park Infection Consultation Service. Part II. Contribution of the service to patient management: an analysis of results between September 1987 and July 1990

The establishment of Infectious Disease teams combining microbiological and clinical expertise has recently been recommended by a joint working part of the Royal College of Physicians and the Royal College of Pathologists. The Northwick Park Infection Consultation Service (ICS) has been operating on these lines since 1983; details are given in Part I. Part II assesses the contribution that the ICS has made to the management of infection in a study of 1038 patients undertaken between September 1987 and July 1990. The areas of patient diagnosis, treatment, investigation and isolation were examined to assess the appropriateness of the attending doctor's management of infection and the benefits resulting from recommendations made by the ICS. At the time of consultation the correct diagnosis had already been made or considered in 93% of patients, essential investigations needed to confirm or refute the diagnosis performed in 92%, and side-room isolation correctly instituted in 81% of patients requiring it. However, 41% of 776 infected patients were receiving suboptimal treatment: this was significantly more frequent in unsolicited consultations (P less than 0.05). Advice was given following consultation in 893 of 1038 patients (86%) and related to treatment (66%), investigation (41%), diagnosis (30%) and patient isolation (4%). Of 844 patients where receipt of advice could be accurately assessed, it was taken fully in 708 (84%), partly in III (13%), and went unheeded in 25 (3%). Advice on diagnosis or investigation enabled the correct diagnosis to be reached in 30% of consultations and in a further 47 patients (5%), the diagnosis was proposed by the ICS on initial consultation.(ABSTRACT TRUNCATED AT 250 WORDS)

Northwick Park Infection Consultation Service. Part I. The aims and operation of the service and the general distribution of infection identified by the service between September 1987 and July 1990 [see comment]

The Northwick Park Infection Consultation Service (ICS) is a collaborative service operated by the departments of Medical Microbiology and Infectious Diseases where personnel and skills are combined. Its aim is to improve the availability and effectiveness of consultation for infection-related problems. This paper sets out the framework for establishing an ICS and also details the general distribution of infection identified by the Northwick Park ICS in a study carried out between September 1987 and July 1990. Part II assesses the contribution that the ICS made to the management of infection. One thousand and thirty-eight (1038) patients were seen on the ICS. Seventy-five per cent (776) were judged to be infected and in 691 this was a probable or certain diagnosis. Skin and subcutaneous tissue, respiratory tract, and genito-urinary tract infections accounted for 64% of the total. Eighty-seven per cent of infections required treatment with intravenous antibiotics, 22% were associated with concomitant bacteraemia, and 2.7% of patients died as a direct result of their infection. Sixty-four per cent of consultations were unsolicited and arose from laboratory results or the clinical information on the form accompanying the specimen: over one quarter were initiated before results were available. These infections were no different in either severity or nature from those identified by solicited requests to either department. Fifty-three per cent of consultations had a moderate to high clinical component. The results emphasise the importance of infection in hospitals and highlight the advantages of a collaborative approach from the departments of Medical Microbiology and Infectious Diseases.

Role of cell-mediated immunity to staphylococci in blepharitis

We studied cell-mediated immunity to staphylococcal antigens in 116 patients with chronic blepharitis and eight normal subjects. Antibodies in tears and blood were measured. Enhanced cell-mediated immunity to Staphylococcus aureus was demonstrated in 46 of 116 patients (40%) in the absence of antibodies to teichoic acid but not among normal subjects. Symptoms of grittiness and morning stickiness were more frequent among patients without enhanced responses. Folliculitis occurred more commonly among patients with enhanced immunity. Marginal keratitis occurred equally among patients with and without enhanced systemic immunity, but patients with enhanced response more commonly required topical corticosteroid therapy. Desensitization to staphylococcal antigens could be investigated as a potential therapeutic approach in selected patients.

Role of staphylococcal toxin production in blepharitis

Lid isolates of Staphylococcus aureus and coagulase-negative staphylococci (CNS) from controls (12 S. aureus and 110 CNS) and from patients with blepharitis (17 S. aureus and 171 CNS) were tested for production of alpha, beta, delta, epsilon, and previously undescribed hemolytic toxins, because toxin production has been implicated as a cause of blepharoconjunctivitis. The electrolyte content of agar media required for toxin production was first investigated. Alpha-lysin was found to be produced by all isolates of S. aureus colonizing lids of normal controls and patients with blepharitis, but by none of 281 CNS isolates. A new toxin was identified, having low molecular weight (5 kd), produced by one CNS strain isolated from a blepharitic lid. It was produced on basic nutrient agar that lacked sodium but contained glucose, which inhibited production of alpha-lysin. It hemolyzed rabbit and sheep erythrocytes and, surprisingly, was neutralized by polyclonal antiserum to alpha-lysin. This may explain occasional reports of alpha-lysin production by CNS. The overall results do not support a hypothesis of hemolytic toxin production by staphylococci as a general cause of blepharitis.

Acanthamoeba keratitis--resistance to medical therapy

Successful medical therapy of Acanthamoeba keratitis has been reported with combination therapy; topical Brolene and neomycin. Resistance has not so far been identified as a problem, but was the basis for recurrent disease observed in a patient with bilateral infection. Eradication of amoebae was finally achieved following prolonged topical therapy and two corneal grafts in each eye. Topical anti-amoebic therapy with paromomycin, benzethonium chloride, clotrimazole and R11/29 (a phenanthridinium compound), was continued for three months post-operatively. No further recurrences occurred during 14 months' follow-up. Drug sensitivities were performed for three isolates of Acanthamoeba sp (group II) which demonstrated the development of resistance to Brolene and arsenic. In addition, the resistant isolates were temperature-sensitive mutants which would not grow at temperatures above 30 degrees C. This could explain 'culture-negative' results in some cases of clinical recurrence when incubation of laboratory samples had only been performed at 37 degrees C.

Encephalitis due to Epstein-Barr virus

Acute encephalitis due to Epstein-Barr virus is described. The initial diagnosis was based on clinical features and a positive Monospot test. Early treatment with intravenous acyclovir was given; steroids were not used. The patient made a rapid and complete recovery from a comatose state. The effectiveness of acyclovir in this condition remains unproven but early treatment is recommended in severely ill patients whose prognosis is uncertain.

Staphylococcal infection and the limbus: study of the cell-mediated immune response

The relationship between enhanced cell-mediated immunity (CMI) to staphylococcal antigens, expressed as delayed hypersensitivity (DH), and the development of catarrhal infiltrates at the limbus in the rabbit has been explored by others. This DH is required for infiltrates to develop in the rabbit cornea when it is exposed to conjunctival inoculation with live Staphylococcus aureus cells. Similar investigations have not been pursued in the human, although St. aureus has been isolated from lids of patients with sterile marginal ulcers. We have tested 69 patients with blepharitis, eleven with and 58 without associated symptomatic marginal keratitis, for DH to killed whole cells of St. aureus and St. epidermidis and protein A; quantitative cultures have also been collected from lids and conjunctivae. Preliminary findings show that nine out of 11 patients with symptomatic marginal keratitis, requiring treatment with steroids, have enhanced DH to St. aureus cell wall antigens. We suggest the hypothesis that this type of marginal keratitis in the human is the result of enhanced CMI at the limbus to St. aureus cell wall antigens.

The paradox of using a 7 day antibacterial course to treat urinary tract infections in the community

1. We have studied determinants of outcome of 7 day courses of treatment in 77 middle aged and elderly patients, in whom the general practitioner's diagnosis of urinary tract infections had been confirmed microbiologically. Bacteria were sensitive to cephalexin or trimethoprim. Where there was no preference, treatments were allocated randomly. Compliance was monitored using a pill box with a concealed electronic device which recorded openings of the box. 2. Prescribing trimethoprim, 200 mg twice daily, was more effective than cephalexin, 250 mg four times daily (cure rates 93 and 67%) (P less than 0.006). Those cured and not cured were not distinguished by age, gender, genitourinary history, or infecting organism. 3. Compliance as measured by box openings was worse for cephalexin than for trimethopim (P = 0.01). However, both totality and pattern of compliance were similar in patients cured and not cured by cephalexin. Thus rigid adherence to a conventional course did not promote cure: fewer doses could have been prescribed. 4. Estimating compliance is essential to clinical trials where medication is self-administered. Poor compliance may establish over exacting regimens. Counting box openings did overestimate compliance, but counting residual tablets overestimated it grossly: given the number of openings less than the ideal, there should have been 171 residual tablets, only 55 were found.

Treatment of relapsing Clostridium difficile diarrhoea by administration of a non-toxigenic strain

Two patients with relapsing Clostridium difficile diarrhoea following metronidazole and vancomycin therapy were colonised with a non-toxigenic avirulent Clostridium difficile strain given orally in three doses. Both patients appeared to respond without side-effects. Oral bacteriotherapy with a defined nontoxigenic strain of Clostridium difficile would appear to represent an acceptable, alternative and novel way to treat hospitalised patients who relapse with Clostridium difficile diarrhoea after specific antibiotic therapy.

Diarrhoea due to enterotoxigenic Clostridium perfringens: clinical features and management of a cluster of ten cases

Clostridium perfringens has recently been shown to be associated with antibiotic-associated diarrhoea. We describe here the clinical features and management of an outbreak of diarrhoea in a Geriatric Unit. Ten cases were due to enterotoxigenic C. perfringens and in these cases there was a highly significant correlation with recent antibiotic administration (P = 0.0001). The importance of early recognition of C. perfringens as a cause of infective diarrhoea in the elderly is stressed.

Necrotising fasciitis due to streptococcus pyogenes

Images