Off-label pharmacological treatment for neuropathic pain: A Delphi study by the Spanish Pain Society Neuropathic Pain Task Force

OBJECTIVES

The use of off-label pharmacotherapies for neuropathic pain (NP) is growing relating to the many unmet needs of patients. However, clinical guidelines fail to address it, and the available evidence is sparse and fragmented. We arranged a formal expert consensus to address this controversial issue and provide some guidance on judicious use.

METHODS

A two-round standard Delphi survey that involved pain clinic specialists with experience in the research and management of NP was done over an ad hoc 40-item questionnaire prepared by the authors. Consensus on each statement was defined as at least either 80% endorsement or rejection after the second round.

RESULTS

Forty-three and thirty-seven panelists participated in the first and second round, respectively. Consensus was reached in 34 out of 40 statements. Endorsed alternatives for unresponsive patients include non-gabapentinoid antiepileptics (oxcarbazepine and eslicarbazepine), venlafaxine, intravenous lidocaine (when doses can be optimized), and some vaporized cannabinoids (under appropriate surveillance). In addition, lacosamide, low-dose naltrexone, propofol, or ketamine could prove beneficial if subjected to more research. Other options were rejected, and there was controversy about the usefulness of topical preparations.

DISCUSSION

For patients who do not respond to standard NP treatments, some other viable pharmacological options can be attempted before advancing to other therapeutic stages. This may help patients who are reluctant to or have some contraindication for interventional therapies.

Evaluation of the Analgesic Efficacy of a Bioelectronic Device in Non-Specific Chronic Low Back Pain with Neuropathic Component. A Randomized Trial

Low energy pulsed electromagnetic signals (PEMS) therapy, in the field of bioelectronics, has been suggested as a promising analgesic therapy with special interest in treating conditions with poor response to pharmacotherapy. This study evaluated the effectiveness of PEMS therapy on the treatment of chronic low back pain patients with a neuropathic component. A group of 64 individuals with such condition was allocated to a 2-week treatment period (10 twenty-minute sessions on consecutive days) with an active PEMS therapy device or an inactive device in random order. The pain was assessed on a visual analog scale, and the functional status was assessed using the SF-12 questionnaire. The visual analog scale scores were lower after treatment than at baseline but only in the group treated with the active device. According to the DN4 score, neuropathic pain decreased in both experimental groups with respect to baseline, but this was only significant for the group treated with the active device. Similarly, an improvement in the SF-12 and Medical Outcomes Study (MOS) sleep scale components was reported. The study demonstrated that low-energy PEMS therapy was efficient in reducing pain and improving function in chronic low back pain patients with a neuropathic component.

Antibodies elicited by the CaniLeish® vaccine: long-term clinical follow-up study of dogs in Spain

The prevention of canine leishmaniosis in healthy dogs requires a multimodal approach combining repellents with an effective vaccine. A vaccine that modulates the cell-mediated immune response against the protozoan has been available in Europe since 2012 (CaniLeish®, Virbac, France). The aim of the present study was to monitor dogs vaccinated with CaniLeish® to examine the kinetics of the antibody response and the safety and tolerance of CaniLeish®. Dogs vaccinated with CaniLeish® were monitored for 12 months. In follow-up visits at baseline (primovaccination or annual booster) (Visit 1, V1), and 1 (V2), 4 (V3), 8 (V4) and 12 (V5) months later, we examined antibody response kinetics using two serology techniques (IFAT and Speed Leish K™). Tolerance to CaniLeish® and its safety were also monitored. Anti-L. infantum IgG antibodies were determined in 242 dogs (125 dogs after primovaccination (Group P) and 117 dogs after booster vaccination (Group B). In addition, 46, 22 and 19 dogs were followed for 2, 3 and 4 years, respectively. At baseline, 100% of dogs in Group P returned negative IFAT and Speed Leish K™ test results while 9.4% (11/117) in Group B tested IFAT positive though Speed Leish K™ negative. In subsequent visits, seropositivity was detected by IFAT in 31.2% (Group P) and 41% (Group B) of the dogs in V2; 16.8% (Group P) and 10.2% (Group B) in V3; 6.4% (Group P) and 8.5% (Group B) in V4; and 3.2% (Group P) and 5.9% (Group B) in V5. All dogs tested Speed Leish K™ negative except two, in which it was later confirmed by molecular testing that they were not infected. Adverse events that could be associated with the vaccine were detected in 20 out of 314 dogs (6.4%). The good clinical status of all dogs was confirmed in an exhaustive clinical exam and haemato-biochemical profile. The Canileish® vaccine was well-tolerated with exceptions that did not appear to be related to age, sex, race or size of vaccinated dogs. Anti-L. infantum antibodies were detected by IFAT in 31.9-40.3% of the dogs 1 month after vaccination, and these antibodies could still be detected in 3.2% of the dogs 1 year later. This means that veterinarians need to use other tools (eg. PCR) to correctly diagnose seropositive dogs.

Controlling phlebotomine sand flies to prevent canine Leishmania infantum infection: A case of knowing your enemy

Leishmaniosis caused by Leishmania infantum is a widespread zoonotic disease that can be transmitted to animals and humans by their vectors, blood-sucking phlebotomine sand flies. To prevent canine leishmaniosis across the whole Mediterranean region, vector control is essential. Because of phlebotomine breeding sites are diverse, environmental larval controls have limited practical value. Control methods of adults are being evaluated, such as selective baits based on sugar feeding of males and females or Attractive Toxic Sugar Baits (ATSB), and the indoor use of Long-Lasting-Insecticidal Nets (LLINs) treated with permethrin to prevent sand fly bites complementing the Indoor Residual Spraying (IRS) approach suggested by WHO. Although several strategies exist, the best control measure to prevent canine Leishmania infantum is to treat dogs using biocidal topical formulations based on legal insecticides (PTs18) or repellents (PTs19) (as collars, spot-ons and/or sprays) during the period when the vectors are active. This means we need to really know the biology and life cycle of the sand fly vector. According to available data, by mapping ambient temperatures we can already predict high risk areas where vector densities will be higher. In ongoing research, new candidates are emerging to fight against sand flies including natural plant extracts with low impacts on the environment and host animal. Other options in the future could be systemic insecticides to help reduce sand fly populations in high density areas. In parallel, health authorities and professionals involved in animal and public health (veterinarians, physicians, entomologists and epidemiologists) must work together in a One Health approach to minimize Leishmania infection. Veterinarians play a crucial role in liaising between key stake holders and dog owners to ensure the latter act responsibly in using repellents as a preventive measure against sand fly bites.

Prevalence of central and peripheral neuropathic pain in patients attending pain clinics in Spain: factors related to intensity of pain and quality of life

Background

The objective of the study was to estimate the prevalence of pure central neuropathic pain (CNP) and peripheral neuropathic pain (PNP) among patients attending pain clinics in Spain. The study also aimed to analyze factors associated with pain intensity and quality of life (QoL).

Methods

A cross-sectional study was performed including 53 patients with pure CNP and 281 with pure PNP attending in 104 pain clinics in Spain. The revised grading system proposed in 2008 to determine a definite, probable or possible diagnosis of NP was used. Pain features, psychological variables and QoL were assessed. Descriptive, bivariate and multivariate analyses were performed.

Results

The prevalence of pure CNP and PNP amongst neuropathic pain patients was 2.4% (95% CI: 1.7;3.1) and 12.9% (95% CI: 1.5;14.3), respectively. Comorbid anxiety, depression or sleep disorders were high in both groups, but higher in CNP patients (51.1%, 71.4%, respectively). Pain intensity in PNP patients was associated with the presence of depression and sleep disturbances. However, in CNP patients, it was related with pain in the lower limbs. The impairment of QoL was greater in CNP patients than in PNP patients; pain location, presence of depression and sleep disturbance were the factors that most negatively affected QoL. Among PNP patients, women and those with higher pain intensity had worse QoL.

Conclusion

Pain intensity and QoL are affected by different factors in patients suffering from CNP or PNP. Identifying these factors could serve to guide therapeutic strategies and improve the QoL of patients.

Naloxegol to Treat Constipation in a Patient Taking Opioids for Cancer Pain: A Case Report

Opioid-induced constipation (OIC) is a common gastrointestinal adverse effect of opioids, which can severely affect compliance and adherence to pain medication regimens and quality of life. Naloxegol has demonstrated efficacy against OIC in several studies involving patients with nonmalignant chronic pain. Here we report efficacy and tolerability of naloxegol in a 68-year-old patient with metastatic lung cancer and severe pain, treated with opioids, who presented with OIC resistant to traditional measures. Addition of naloxegol produced rapid improvement in his OIC symptoms and no apparent adverse effects while taking extended-release morphine 130 mg orally every 12 hours.

A survey of perceptions, attitudes, knowledge and practices of medical oncologists about cancer pain management in Spain

PURPOSE

To monitor oncologists' perspective on cancer pain management.

METHODS

An anonymized survey was conducted in two waves. First, over a convenience sample of oncologists known to be particularly concerned with the management of pain. Second, using a random sample of oncologists.

RESULTS

In total, 73 and 82 oncologists participated in the first and second wave, respectively. Many oncologists reported to have good knowledge of analgesic drugs (95.9%), the mechanism of action of opioids (79.5%), and good skills to manage opioid-related bowel dysfunction (76.7%). Appropriate adjustment of background medication to manage breakthrough pain was reported by 95.5% of oncologists. Additionally, 87.7% (68.3% in the second wave, p = 0.035) of oncologists reported suitable opioid titration practices, and 90.4% reported to use co-adjuvant medications for neuropathic pain confidently. On the other hand, just 9.6% of oncologists participated in multidisciplinary pain management teams, and merely 30.3 and 27.1% reported to routinely collaborate with the Pain Clinics or involve other staff, respectively. Only 26.4% of the oncologists of the second wave gave priority to pain pathophysiology to decide therapies, and up to 75.6% reported difficulties in treating neuropathic pain. Significantly less oncologists of the second wave (82.9 vs. 94.5%, p = 0.001) used opioid rotation routinely.

CONCLUSIONS

Unlike in previous surveys, medical oncologists reported in general good knowledge and few perceived limitations and barriers for pain management. However, multi-disciplinary management and collaboration with other specialists are still uncommon. Oncologists' commitment to optimize pain management seems important to improve and maintain good practices.

Flea species infesting dogs in Spain: updated spatial and seasonal distribution patterns

This entomological survey examines the spatial and seasonal distribution patterns of flea species infesting dogs in Spain. Bioclimatic zones covering broad climate and vegetation ranges were surveyed according to size. In a cross-sectional spatial survey carried out from late May 2013 to mid-July 2015, 1084 dogs from 42 different locations were examined. A total of 3032 fleas were collected and identified as belonging to the following species: Ctenocephalides felis (Siphonaptera: Pulicidae) (81.7%, 2476 fleas); Ctenocephalides canis (11.4%, 347 fleas); Pulex irritans (Siphonaptera: Pulicidae) (6.9%, 208 fleas), and Echidnophaga gallinacea (Siphonaptera: Pulicidae) (0.03%, one flea). Variables observed to have effects on flea abundance were animal weight, sex, length of hair and habitat. In the seasonal survey conducted from June 2014 to June 2015, 1014 fleas were collected from 239 dogs at 30 veterinary practices across Spain. Peaks in C. felis abundance were observed in early summer and late autumn, whereas high numbers of P. irritans and C. canis were recorded in autumn. Numbers of fleas detected in winter were low overall. Based on these findings, the present study updates the spatial and seasonal distributions of flea species in Spain and assesses the impacts of host and habitat variables on flea infestation.

Cross-sectional evaluation of patient functioning and health-related quality of life in patients with neuropathic pain under standard care conditions

AIM

The purpose of this cross-sectional evaluation was to determine the impact of neuropathic pain (NeP) on patient functioning and Health-Related Quality of Life (HRQoL) under standard care conditions.

METHODS

Patients with NeP or neuropathic and nociceptive pain [Mixed Pain (MP)] enrolled in the DONEGA study, a naturalistic, prospective and multi-centre study of the effectiveness of gabapentin under usual care conditions, were included in this cross-sectional evaluation before starting study treatments. Participants completed the Short Form-McGill Pain Questionnaire, MOS Short Form-12 (SF-12), and Sheehan Disability Scale (ShDS). Multivariate analysis and regression models were used to analyze patient data.

RESULTS

A total of 1519 patients [mean+/-SD; 56.0+/-13.7 yrs old (58.8% female)] with NeP or MP were enrolled in the study. The mean pain history was 1.1+/-2.8 yrs, current pain intensity on a 5-point visual analogue scale was 2.8+/-1.0 and mean pain in previous week was 71.3+/-19.0mm. Pain substantially interfered (i.e., score > or = 5 on 0-10 scale) with normal work (5.9+/-3.0), social life (5.7+/-3.0), and family life (5.3+/-3.0), producing substantial disability (total ShDS score of 16.9+/-8.3 pts). Country-standardised physical (PCS) and mental health (MCS) component summary scores of SF-12 indicated significant impairment in both domains compared with the general Spanish population: PCS; -1.13+/-1.0 SDS (standard deviation score), and MCS; -1.21+/-0.7 SDS, equivalent to the 15th and 25th percentiles of normative populations, respectively.

CONCLUSIONS

Under standard care conditions, neuropathic and mixed pain are associated with impaired physical and mental QoL, producing a substantial level of disability in these patients.

Is morphine still the best reference opioid?

SUMMARY Cancer and noncancer pain can usually be managed according to the WHO analgesic ladder and, in many countries, morphine remains the first-line opioid of choice for chronic severe pain. There have been many advances in the use of opioids for moderate-to-severe pain control in recent years. Consequently, the position of morphine as the gold standard became gradually more questioned, mostly because of serious adverse effects and the availability of different opioids and new formulations. The place of morphine as the first-line option is based on reasons of familiarity, availability or cost rather than medical advantages. In recent years, a number of systematic reviews failed to demonstrate superiority of morphine over other opioids in terms of efficacy or tolerability. Moreover, some strong opioids have shown improved tolerability or convenience. Currently, morphine might still be considered as a reference drug for equivalent dosing, but not for strategic healthcare decisions, as it has not demonstrated clinical or pharmacological superiority over other opioids. Therefore, there is a lack of evidence to sustain the role of morphine as the gold standard in the treatment of chronic severe pain.

Questionnaire-based survey on the clinical management of canine leishmaniosis in the Madrid region (central Spain)

This paper describes a questionnaire designed to gain information on how veterinarians clinically manage canine leishmaniosis (CanL) in the Madrid region (central Spain). The present survey is one of the several similar questionnaire-based surveys conducted within the framework of the project EDEN (Emerging Diseases in a changing European eNvironment). The questionnaire sought to obtain data regarding the main clinical manifestations observed, the diagnostic methods used and the preventive measures recommended. Its Spanish version was sent by post to veterinary practitioners within the study area in two lots, one sent out in December 2006 and the other in March 2007. Only 174 of the 760 questionnaires sent were completed and returned (reply rate of 23%). Among the completed questionnaires, clinics differed widely in terms of features such as the habitats of the dogs (urban, peri-urban or rural) and patient volumes. Clinics attending dogs from peri-urban/rural habitats reported more suspected (p<0.001), confirmed (p=0.001) and newly diagnosed (p=0.001) cases/year than clinics providing service to a city clientele alone. According to the veterinary practitioners, skin lesions, lymphadenomegaly and weight loss were commonly observed, although these signs are not specific to CanL. Signs described to be of high diagnostic value were epistaxis and kidney disease. All the veterinarians polled reported that a suspicion of Leishmania infantum infection was confirmed by at least a serological method; the immunofluorescence antibody test (IFAT) being the technique most used. To prevent the disease, most vets recommended topical synthetic pyrethroids applied as impregnated collars or spot-ons. It is observed that despite considerable progress is being made in clinical management and controlling the disease, in Madrid Region its incidence continues to increase.

Tapentadol in the management of chronic low back pain: a novel approach to a complex condition?

Chronic pain affects approximately 1 in 5 people in Europe, and around half of sufferers receive inadequate pain management. The most common location is the lower back. Pharmacological treatment of this condition is challenging because of the range of causative mechanisms and the difficulty of balancing analgesic efficacy and tolerability. An international panel of clinical pain specialists met in September, 2009, to discuss the treatment of chronic low back pain, and to review preclinical and clinical data relating to the new analgesic, tapentadol. A lack of consensus exists on the best treatment for low back pain. The range of regularly prescribed pharmacological agents extends from nonopioids (paracetamol, NSAIDs, and COX-2 inhibitors) to opioids, antidepressants and anticonvulsants. Pain relief may be compromised, however, by an undetected neuropathic component or intolerable side effects. Treatment is potentially life-long and effective analgesics are urgently needed, with demonstrable long-term safety. Combining separate agents with different mechanisms of action could overcome the limitations of present pharmacological therapy, but clinical evidence for this approach is currently lacking. Tapentadol combines μ-opioid agonism with noradrenaline reuptake inhibition in a single molecule. There is strong evidence of synergistic antinociception between these two mechanisms of action. In preclinical and clinical testing, tapentadol has shown efficacy against both nociceptive and neuropathic pain. Preclinical data indicate that tapentadol’s μ-opioid agonism makes a greater contribution to analgesia in acute pain, while noradrenaline reuptake inhibition makes a greater contribution in chronic neuropathic pain models. Tapentadol also produces fewer adverse events than oxycodone at equianalgesic doses, and thus may have a ‘μ-sparing effect’. Current evidence indicates that tapentadol’s efficacy/tolerability ratio may be better than those of classical opioids. However, further research is needed to establish its role in pain management.

Seasonal trends and spatial relations between environmental/meteorological factors and leishmaniosis sand fly vector abundances in Central Spain

This paper reports on an entomological survey performed over the period 2006-2008 in Central Spain (mainly in the Madrid province) where canine leishmaniosis (CanL) is endemic. The study area was selected on the grounds of its wide altitude range, which determines both broad climate and vegetation ranges that could affect sand fly distributions. This area was surveyed from NE to SW across its mountain range (Sistema Central) and plateau area using sticky traps mainly on embankments. In 2006 and 2007, 123 sites were sampled (9557 sand flies captured) to establish possible relations between environmental or meteorological factors and vector densities (Phlebotomus perniciosus and Phlebotomus ariasi). The factors correlated with higher vector densities were: a sample site between villages or at the edge of a village, the lack of a paved road, a rural habitat, an east or south-facing wall or wall sheltered from the wind, the presence of livestock or birds, a holm-oak wood vegetation, a lower summer mean temperature and lower annual mean precipitation. This study was followed by a seasonal survey conducted at 16 selected sites (14,353 sand flies) sampled them monthly from May to November 2008. P. perniciosus showed a diphasic seasonal trend with two abundance peaks in July and September whereas P. ariasi showed a monophasic trend with one peak in August. Comparing with data from studies performed in 1991 in the same area, vector densities are significantly higher. A possible explanation for this is that the vectors (mainly P. ariasi) are moving towards higher altitudes perhaps because of global change. This increasing trend could have an impact on CanL and its geographical distribution.

Cognitive impairment in patients with fibromyalgia syndrome as assessed by the mini-mental state examination

Background

This study evaluated the frequency of cognitive impairment in patients with Fibromyalgia syndrome (FMS) using the Mini Mental State Examination (MMSE).

Methods

We analyzed baseline data from all 46 patients with FMS and 92 age- and sex-matched controls per diagnosis of neuropathic (NeP) or mixed pain (MP) selected from a larger prospective study.

Results

FMS had a slight but statistically significant lower score in the adjusted MMSE score (26.9; 95% CI 26.7-27.1) than either NeP (27.3; 95% CI 27.2-27.4) or MP (27.3; 27.2-27.5). The percentage of patients with congnitive impairment (adjusted MMSE ≤ 26) was numerically higher in FMS (15%; 95% CI 6.3-29) compared with NeP (5%; 95% CI 1.8-12.2) or MP (5%; 95% CI 1.8-12.2) and higher than in the same age stratum of the general population (0.05%).

Conclusions

Compared with the population reference value, patients with FMS showed high frequency of cognitive impairment.

[Linguistic adaptation into Spanish and psychometric validation of the ID-Pain questionnaire for the screening of neuropathic pain]

BACKGROUND AND OBJECTIVE

To achieve a linguistic adaptation and psychometric validation into Spanish of the ID-Pain questionnaire for the screening of differential diagnosis of pain with a neuropathic component.

MATERIAL AND METHOD

Cross-sectional validation study carried out in 2 phases (cultural adaptation into Spanish language and validation study to test psychometric properties of the scale) in men and women > 18 years, with neuropathic (NP) and nociceptive (NNP) chronic pain for more than 6 months. Feasibility and reliability were explored. Criterion and convergent validity were studied by means of ID-Pain association with reference diagnosis and LANNS (Leeds Assessment of Neuropathic Symptoms and Signs) scale scores. Factor and ROC curves analysis, agreement with reference diagnosis and sensitivity and specificity values were assessed.

RESULTS

A total of 283 subjects -64.4% women; mean age (standard deviation): 59.1 (14.9) years-, 145 (51.2%) with NP and 138 (48.8%) with NNP were included in the study. Administration time was 4.2 (3.0) min. Only 15% of participants required help for test completion. Factor analysis indicated a unifactorial solution accounting for 35.5% of the variance. The instrument was time-stable (test-retest r-Pearson = 0.98; p < 0.0005). Mean score differentiated NP from NNP patients; 3.5 (1.2) vs. 1.2 (1.4) (p < 0.0005). Optimum cut-off value was > or = 3 points, showing an area under the curve = 0.89; p < 0.0005, sensitivity value of 0.81, specificity of 0.84 and kappa coefficient of agreement with reference clinical diagnosis of 0.65. The scale also showed good concurrent validity with LANSS classification of subjects (kappa = 0.61; p < 0.0005).

CONCLUSIONS

The Spanish version of the ID-Pain questionnaire is feasible, reliable and appropriated as a self-administered screening tool for pain with a neuropathic component.

Analgesic efficacy of zoledronic acid and its effect on functional status of prostate cancer patients with metastasis

OBJECTIVES

A multi-centered observational study evaluated the efficacy of zoledronic acid for improving pain and mobility, and preventing skeletal-related events (SRE) (fracture, spinal compression, pain-relieving radiotherapy), in patients with prostate cancer and bone metastasis.

MATERIALS AND METHODS

Males (n = 218) with prostate cancer and bone metastasis undergoing oncologic therapy received zoledronic acid (4 mg iv/month) for 6 months. Parameters evaluated were: 1) pain and movement after 2 consecutive doses; 2) quality of life; 3) SRE incidence and time-to-appearance. Medication tolerance and treatment satisfaction were assessed using a questionnaire.

RESULTS

A total of 170 that matched all the inclusion criteria (78%) out of 218 were evaluable for efficacy. There was a measurable statistically significant reduction in pain at rest and on movement as well as an improvement in the quality of life compared with baseline. Best results were obtained with early treatment. Overall incidence of bone events was 11.2%. Of the 212 patients (97.2%) evaluable for safety, 16% suffered adverse events and 66% expressed satisfaction with the treatment

DISCUSSION

Zoledronic acid is effective for reducing pain, improving mobility, and increasing the quality of life in patients with prostate cancer with bone metastasis. Its easy administration and good tolerability make zoledronic acid one of the principal therapeutic tools in the management of patients with pain associated with bone metastasis from prostate cancer.

[Linguistic adaptation and Spanish validation of the LANSS (Leeds Assessment of Neuropathic Symptoms and Signs) scale for the diagnosis of neuropathic pain]

BACKGROUND AND OBJECTIVE

This study was intended to achieve a linguistic adaptation and validation into Spanish of the LANNS scale for the differential diagnosis of neuropathic pain.

MATERIAL AND METHOD

Cross-sectional validation study carried out in two phases: first, cultural adaptation into Spanish language, by means of a conceptual equivalence approach, including forward and backward translations in duplicate and review by experts; and second, validation study of the scale in patients with neuropathic, noniceptive and mixed pain, in which the scale properties of reliability (internal consistency and inter-rater agreement with kappa and intra-class correlation coefficients) and validity (ROC curves analisys, agreement with reference diagnosis and determination of sensitivity, specificity and positive and negatives predictive values) were evaluated.

RESULTS

A total of 156 subjects (90 women, 58.4%), 89 with pain of neuropathic origin (mean age [SD], 59.6 [19.4] years, 22 with mixed pain due to radiculopathy) and 67 with nociceptive pain (66.6 [11.8] years) were included in the study. Diagnosis of the type of pain was performed by standard clinical criteria. The scale was administrated by trained interviewers, in duplicate and blinded to the reference diagnosis. The scale showed good reliability (internal consistency: Cronbach and Guttman split-half coefficients between 0.68 and 0.71; inter-rater agreement: kappa coefficient of 0.70 and intra-class correlation coefficients between 0.77 and 0.92) and validity for a cut-off value > or = 12 points, which represented the best value to discriminate between patients with neuropathic and nociceptive components of pain (kappa coefficient = 0.70; CI 95%, 0.59-0.81; p < 0.0001); area under the curve, 0.929; (p < 0.0001); specificity, 89.4% (CI 95%, 79.4%-95.6%) and positive value, 91.1%; CI 95%, 82.6%-96.4%).

CONCLUSIONS

The Spanish version of the LANSS scale is reliable and valid for the differential diagnosis of neuropathic pain.

Cognitive function impairment in patients with neuropathic pain under standard conditions of care

The objective of this study is to analyze the prevalence to cognitive function impairment (CI) in a pragmatic cohort of subjects with different types of neuropathic pain under standard conditions of care by means of a cross-sectional baseline analysis of a sample of patients with NeP enrolled in a pragmatic, prospective, multicenter study evaluating the effectiveness of gabapentin. A total of 1519 patients (58.8% women), aged > or =18 years (mean [SD]=56.0 [13.7]), with neuropathic or mixed neuropathic and nociceptive pain for a mean (SD) of 1.1 (2.8) years were enrolled in the study. Pain was assessed with the short form of the McGill Pain Questionnaire, and cognitive function was measured with the Mini-Mental State Examination (MMSE). A score < or =24 on the MMSE was considered as CI. Multivariate logistic regression models were used to estimate CI prevalence. CI prevalence was substantially higher in patients with NeP than that reported in the general Spanish population, and significantly higher than in patients with mixed neuropathic and nociceptive pain: 11.4% (8.5%-14.3%) vs. 6.4% (4.6%-8.7%), P=0.006 (adjusted odds ratio=1.88 [1.21-2.91]). Prevalence significantly increased with age, up to 32.2% (20.6%-45.6%) in those with NeP, and to 28.2% (15.0%-44.9%) in those with mixed syndromes, for the age group > or =75 years, P<0.001 within age groups. Symptoms of anxiety and obesity, and to a lesser extent, symptoms of depression, were also factors associated with a higher prevalence rate of CI. This analysis showed that, after adjusting for confounding factors, the prevalence of CI was substantially higher in patients with NeP than those with mixed pain and the reference general population. Age, anxiety, depression, and obesity were factors found to be significantly associated with CI.

Evaluation of a spray of permethrin and pyriproxyfen for the protection of dogs against Phlebotomus perniciosus

Dogs are the main domestic reservoir of Leishmania infantum in the Old World (Leishmania chagasi in the New World) a parasite responsible for many cases of human visceral leishmaniasis in both endemic and non-endemic regions. One strategy for the control of leishmaniasis would be to prevent dogs from being bitten by sandflies, the vector of leishmaniasis. This study was designed to assess the efficacy of spraying a combination of permethrin and pyriproxyfen on to dogs artificially exposed to sandflies. Two groups of four male dogs, one of them treated and the other left untreated as controls, were exposed for one hour to 100 female sandflies seven days before the treatment, on the day of treatment and seven, 14, 21, and 28 days later. After each exposure, sandflies were collected, counted and scored. The prevention of sandfly bite was calculated by measuring the number of fed sandflies (dead and alive) after treatment. In this experimental assay, the repellent effect of the treatment against sandfly bites after 21 days was 71.4 per cent, but the insecticidal effect was only 7.2 per cent.

Levels of HSP70 in HIV+ patients in different viroimmunological states

The aim of the study was to establish an association between the viroimmunological status of HIV positive patients and their levels of the 70-kD heat shock protein (Hsp70). The longitudinal retrospective case study involved 61 patients at the University Hospital in Granada (Spain) from 1999 to 2002. Twenty-five patients were viroimmunologically stable, while the other 36 patients had suffered virological failure. A minimum of three blood samples were taken at intervals of at least 3 months for the patients who were stable virologically and immunologically, whereas four samples were taken for the virological failure group: two previous to the onset of virological failure, a third corresponding to the time of virological failure, and a fourth at least 3 months after remission of virological failure. Blood samples were also obtained from 20 healthy control subjects; Hsp70 levels in all were determined by enzyme immunoassay. The mean concentration of Hsp70 was 145.4 ng/ml in the HIV-infected patients as opposed to 72.1 ng/ml in the controls. While the viroimmunologically stable group showed levels similar to those of the controls (66.5 ng/ml), the mean value of Hsp70 in the virological failure group was nearly four times as high (249.1 ng/ml), yet this difference was not statistically significant. The patients treated with reverse transcriptase inhibitors were found to have significantly higher levels of Hsp70 than the other subjects. The transformed variable Hsp70/CD4(+) presents less variability than the Hsp70 value itself, giving a higher degree of statistical significance, and may be considered a useful parameter for diagnostic, prognostic, and therapeutic management of HIV positive patients.

[Prevalence of neuropathic pain in Spain: clinical, working and health care implications]

A narrative systematic medical literature review on prevalence of neuropathic pain (NP) in Spain from 1990 to 2004 was conducted. The average number of publications was 3 per year. Prevalence data varied depending on studied population, definition of pain/pathology and time of pain evolution. The most commonly studied pathologies included: mononeuropathies and polyneuropathies: 42%, multiple sclerosis: 35% and entrapment neuropathies: 16%. Some episodes of NP were left untreated. One third of patients with back pain receiving analgesic treatment still had high intensity pain. Future studies on the prevalence of NP should use work definitions and criteria reached by consensus. An awareness of the clinical presentation of NP and an appropriate and early treatment could minimize its clinical, working and health care implications. NP is a diverse and highly prevalent condition in Spain. Efforts should be conducted towards the achievement of diagnostic criteria consensus and higher rates of analgesic success.

Pregabalin reduces pain and improves sleep and mood disturbances in patients with post-herpetic neuralgia: results of a randomised, placebo-controlled clinical trial

This study was designed to assess the efficacy and safety of pregabalin-a novel alpha(2)-delta ligand with analgesic, anxiolytic, and anticonvulsant activity-for treating neuropathic pain in patients with post-herpetic neuralgia (PHN). Two hundred and thirty-eight patients were randomised into this multicentre, doubleblind, placebo-controlled trial to receive 150 (n=81), 300 mg/day (n=76) pregabalin, or placebo (n=81) for 8 weeks. Among the exclusion criteria was failure to respond to previous treatment for PHN with gabapentin at doses > or =1200 mg/day. Endpoint mean pain scores were significantly reduced in patients receiving 150 or 300 mg/day pregabalin compared with placebo. Efficacy was observed as early as week 1 and was maintained throughout the study. Significantly more patients in both pregabalin groups (150 mg, 26%; 300 mg, 28%) were responders (> or =50% decrease in mean pain score from baseline to endpoint) than in the placebo group (10%). Additionally, by week 1 and for the study's duration, 150 and 300 mg/day pregabalin significantly reduced weekly mean sleep interference scores. More pregabalin-treated patients than placebo-treated patients reported that they were 'much improved' or 'very much improved'. Health-related quality-of-life (HRQoL) measurements using the SF-36 Health Survey demonstrated improvement in the mental health domain for both pregabalin dosages, and bodily pain and vitality domains were improved in the 300 mg/day group. The most frequent adverse events were dizziness, somnolence, peripheral oedema, headache, and dry mouth. Pregabalin efficaciously treated the neuropathic pain of PHN. Additionally, pregabalin was associated with decreased sleep interference and significant improvements in HRQoL measures.

[Venlafaxine extended release for the treatment of chronic pain. A series of 50 cases]

INTRODUCTION

The objective of this study is to investigate analgesic effectiveness and safety of venlafaxine extended release in chronic pain of any etiology.

METHODS

Six month, observational, open study, carried out in two pain units. Initially, a daily dose of 75 mg of venlafaxine extended release was administered, increasing it to 150 mg, following clinical criteria. Treatment response was measured using the Visual Analogue Scale (VAS), rest and mobilization, Hospital Anxiety and Depression Scale (HAD) and Eastern Cooperative Oncology Group (ECOG) and an adverse event sheet to record adverse events occurring during the study.

RESULTS

The study was carried out in a 50 patient sample with a mean age of 57.1 +/- 1.8 years, with chronic pain. A total of 85-90 % of the patients was maintained with a daily dose of 75 mg of venlafaxine extended release. This produced a gradual reduction of the VAS scores at rest (significant reduction of 5.2 +/- 1.1 to 2.7 +/- 1.5 points; (p<0.0005) and mobilization (significant reduction of 5.5 +/- 0.8 to 3.1 +- 1.6 points; p<0.0005). Pain relief increased progressively. Regarding physical activity measured by the ECOG scale, there was a reduction of the percentage of patients and increase of outpatients. Tolerability to venlafaxine was "excellent", "very good" or "good" for 72% of the patients.

CONCLUSIONS

Extended release venlafaxine can be an effective and well-tolerated treatment in patients with chronic pain of any etiology, although it must be investigated in depth.

Double-blind evaluation of short-term analgesic efficacy of orally administered dexketoprofen trometamol and ketorolac in bone cancer pain

The analgesic efficacy and safety of dexketoprofen trometamol (the active enantiomer of the racemic compound ketoprofen) (25mg q.i.d.) vs. ketorolac (10mg q.i.d.) was assessed in 115 patients with bone cancer pain included in a multicenter, randomized, double-blind, parallel group study. A level of >/=40 mm on the 100 mm visual analog scale (VAS) and >/=10 in the pain rating index were required for inclusion. At the end of treatment on day 7 (+1 day), mean values of VAS were 32+/-24 mm for dexketoprofen and 40+/-30 mm for ketorolac (P=0.12) but the pain rating index was significantly lower in patients given dexketoprofen (8.5+/-2.3 vs. 9.7+/-2.9, P=0.04). Moreover, most of the patients reached a pain intensity difference from baseline >/=20 mm (75% of patients for dexketoprofen and 65% of patients for ketorolac). Around half of patients in both treatments had a pain intensity <30 mm on VAS at the end of treatment (55% for dexketoprofen and 47% for ketorolac). In the overall assessment of efficacy, a higher percentage of both patients and physicians rated dexketoprofen as 'quite effective' or 'very effective' compared to ketorolac. The percentage of patients withdrawn from the study for any reason as well as for insufficient therapeutic effect or due to adverse events was lower in the dexketoprofen group than in the ketorolac group. Treatment-related adverse events occurred in 16% of patients given dexketoprofen and in 24% given ketorolac. Serious adverse events occurred in 3.5% of patients from both groups but only one case of gastrointestinal hemorrhage was considered related to ketorolac. We conclude that dexketoprofen trometamol 25 mg q.i.d. oral route is a good analgesic therapy in the treatment of bone cancer pain, comparable to ketorolac 10 mg q.i.d., with a good tolerability profile.

[Validation of the Spanish version of the Brief Pain Inventory in patients with oncological pain]

BACKGROUND AND OBJECTIVE

Our goal was to validate the Spanish version of the Brief Pain Inventory (BPI) questionnaire used to measure the intensity of oncological pain and its impact on activities of daily living in patients with cancer.

PATIENTS AND METHOD

Patients with oncological pain were consecutively included in the study. These patients filled up the Spanish version of the BPI questionnaire (CBD) and the Rotterdam Symptom Checklist (RCSL) during the inclusion visit and again after 3-5 days (patients with clinically stable oncological pain) or after one month (patients with unstable oncological pain).

RESULTS

126 patients were assessed; 85.1% of them had suffered some episode of irruptive pain 24 hours prior to their inclusion in the study. 86.5% of patients fully completed the questionnaire. The CBD showed mild to moderate correlations with the patients perception of pain severity and with the presence of tumor dissemination. The <<psychological symptoms>> dimension of the RCSL displayed the highest correlation with the dimensions of the BPI (<<pain intensity>> and <<interference in activities of daily living>>). The internal consistency and the test-retest reliability between dimensions were good (0.87 and 0.89) and low to moderate (0.53 and 0.77), respectively. The CBD questionnaire was found to be a tool capable of detecting changes in pain intensity. The changes observed in the two CBD dimensions between study visits fairly reflected the patients perceived changes in pain intensity.

CONCLUSIONS

The Spanish version of BPI is valid for measuring the intensity of oncological pain and its impact on activities of daily living in conditions of usual clinical practice.

Ruthenium and ruthenium dioxide-modified graphite-ethylene/ propylene/diene and graphite-teflon composite electrodes as amperometric flow detectors. Application to the determination of methionine

The flow injection amperometric performance of solid composite graphite electrodes with ethylene/propylene/diene (EPD) or Teflon as binding agents, and with Ru or RuO2 particles as electrocatalytic modifiers has been compared. Both, Ru and RuO2 modified electrodes exhibited electrocatalytic properties on the methionine oxidation process in alkaline media. The electrodes composition and the hydrodynamic and chemical variables were optimized. Graphite-EPD (GEPD) electrodes showed a better analytical performance than graphite-Teflon (GPTFE) electrodes. Furthermore, a better sensitivity, repeatability and reproducibility was observed for RuO2-GEPD electrodes when compared with Ru-GEPD electrodes. At an applied potential of +0.50 V, a detection limit for methionine of 4.8x10(-5) mol L(-1), similar to those reported in the literature for other RuO2-modified electrodes, was obtained. The analytical applicability of RuO2-GEPD electrodes was demonstrated by determining methionine in a complex pharmaceutical formulation.

Double-blind parallel comparison of multiple doses of ketorolac, ketoprofen and placebo administered orally to patients with postoperative dental pain

Ketorolac 10 and 20 mg, ketoprofen 50 mg and placebo were compared in a multiple-dose, double-blind, randomized analgesic study that included 150 patients with pain after impacted third molar removal. Patients evaluated their study medication over a 48 h period. Bivariate and multivariate analysis revealed statistically significant differences between the different medications studied, evaluated by the consumption of rescue medication (50.4-80.4% of the placebo group required rescue versus 17.0-47.6% of the ketoprofen, 5.7-31.9% of the ketorolac 10 mg and 1.8-22.5% of the ketorolac 20 mg groups), the pain relief experienced by the patient (P<0.05), and the overall efficacy of the medication (P<0.05). The efficacy of ketorolac 10 mg did not differ from that of ketorolac 20 mg, and both were more efficacious than ketoprofen 50 mg, which in turn was more efficacious than the placebo. One-third of the placebo group did not require rescue medication. The factors with the greatest influence on the use of rescue medication were the analgesic taken by the patient and the presence or not of postoperative inflammation.

Oil-in-water emulsions as suitable working media for the direct polarographic determination of aziprotryne and desmetryne from its organic extracts in water samples

The electroanalytical behavior of the reduction of the herbicides aziprotryne (2-azido-4-isopropylamino-6-methylthio-1,3,5-triazine) and desmetryne (4-isopropylamino-6-methylamino-2-methylthio-1,3,5-triazine) in oil-in-water emulsions is reported. This medium allows the differential pulse polarographic determination of these s-triazines directly from their sample extracts in an appropriate organic solvent. Sodium pentanesulfonate was chosen as the most suitable surfactant to be used as emulsifying agent, whereas ethyl acetate was selected as the organic solvent to form the emulsions. The peak current was maximum in a 0.3 mol L(-1) HClO4 medium of the continuous aqueous phase for aziprotryne, and at pH 3.0 for desmetryne, and the potential became more negative as the pH increased for both herbicides. The limiting current is diffusion controlled and the electrode process is irreversible. Four electrons are involved in the overall electrochemical reduction process as determined by controlled potential coulometry, whereas the alpha n(a) values suggested that two electrons are involved in the rate-determining step. Using differential pulse polarography, aziprotryne and desmetryne can be determined in the emulsified medium over the concentration ranges 1.0 x 10(-7)-1.0 x 10(-4) mol L(-1), with limits of detection of 4.5 x 10(-8) mol L(-1) and 6.6 x 10(-8) mol L(-1), respectively. The method was applied to the determination of aziprotryne and desmetryne in spiked irrigation water. At concentration levels of 6.0 x 10(-7) mol L(-1) aziprotryne and 4.0 x 10(-7) mol L(-1) desmetryne, recoveries of 94 +/- 3% and 94 +/- 4%, respectively, were obtained after preconcentration on Sep-Pack C18 cartridges. Finally, partial least-squares regression (PLSR) has been used for treatment of the polarographic data obtained from mixtures of aziprotryne, desmetryne and simazine in oil-in-water emulsions. The size of the calibration set was of 29 samples by ninety two current measurements at different potentials. Prediction of the herbicides concentration within the range 1.0 x 10(-6)-1.0 x 10(-5) mol L(-1) was possible.

Pathologic intrathyroidal parathyroid glands

BACKGROUND

Parathyroid glands originate from the third and fourth branchial pouches and migrate caudally to their final positions. Aberrations during migration result in anomalous locations. Intrathyroidal location is not common.

METHODS

We reviewed cervical explorations performed from 1974 to 1993 in hyperparathyroidism patients.

RESULTS

We found pathological intrathyroidal glands in six patients. Three patients had adenomas (left superior, left inferior and right inferior glands). The hyperplastic glands were left inferior in one patient and right inferior in the remaining two. Intraoperative diagnosis was made in three cases in which palpation of the thyroid gland showed a nodule that was suspected to be the parathyroid missing gland. In three patients it was a finding in thyroidectomy or hemithyroidectomy specimens, two of them with associated thyroid nodular disease.

CONCLUSIONS

Ipsilateral thyroidotomy on the side of a palpable thyroid mass or blind hemithyroidectomy are justified if a presumably pathological intrathyroidal gland is suspected, when all other sites in the neck have been excluded.

Long tracheobronchial and esophageal rupture after blunt chest trauma: injury by airway bursting

Tracheobronchial rupture can be associated with blunt thoracic trauma. An important factor in the physiopathology of these lesions is reflex closure of the glottis, which can be related to closed chest trauma. We report a case of nonpenetrating thoracic trauma that caused a long membranous tracheal rupture from the subcricoid area to the main carina, extending to both main bronchi. In addition, a complex esophageal rupture occurred due to the great energy liberated by the airway rupture acting as a real tracheal burst. Both lesions were diagnosed by flexible bronchoscopy. The postoperative period was without serious complications.

Efficacy and tolerance of oral dipyrone versus oral morphine for cancer pain

In a double-blind, randomised and parallel clinical trial, two oral doses of dipyrone (1 and 2 g) administered every 8 h were compared with 10 mg of oral morphine given every 4 h for the relief of chronic cancer pain. A total of 121 patients with cancer pain without gastric involvement participated in a 7-day treatment course and were allocated to receive either dipyrone 1 g (n = 41), dipyrone 2 g (n = 38) or morphine (n = 42). Drug efficacy was analysed according to the degree of pain relief using a 100-mm visual analogue scale, and the number of patients who decided to increase the dose of the analgesic drug on day 4. The analgesic effect of dipyrone, 2 g every 8 h, was similar to that of morphine. The efficacy of both schedules was significantly greater than that of dipyrone, 1 g every 8 h. Dipyrone at either 1 or 2 g doses tended to be better tolerated than morphine, although the differences were not statistically significant.

[Possible recall bias in a case-control study of congenital hip dysplasia]

PURPOSE

To ascertain the presence of recall or report bias in a case-control study on congenital dysplasia of the hip (CDH).

METHODS

A hospital case-control study was performed. Those cases and controls with other malformations or from mothers with clinical problems were discarded. 97 cases of dysplasia, and 164 controls were collected. Mother's life style was assessed. Odds ratios (OR) (crude and multiple-factor adjusted by logistic regression analysis) and their 95% confidence intervals were estimated. Risk factors were analyzed stratifying by the results of Ortolani-Barlow maneuver, since women were interviewed after knowing these results.

RESULTS

Mothers of newborns with a positive Ortolani-Barlow maneuver yielded a higher OR for positive family history than those of babies with a negative one (2.27 versus 1.38). Overall smoking and alcohol consumption, and number of health exams during pregnancy yielded a negative association with CDH. In these cases closer-to-the-null ORs were obtained in newborns with positive Ortolani-Barlow.

CONCLUSIONS

The presence of a report or recall bias is suggested as one of the possibilities for explaining the results.

Influence of socioeconomic and health care development on infant and perinatal mortality in Spain 1975-86

STUDY OBJECTIVE

This study aimed to analyse the influence of social, economic, and health development on infant and perinatal mortality in Spain between 1975 and 1986, and to identify possible changes in these relationships over time.

DESIGN

Study of the association between mortality and a range of variables.

SETTING

50 Spanish provinces.

MEASUREMENTS AND MAIN RESULTS

Mean infant and perinatal mortality were estimated for two periods--1975-8 and 1983-6. Social, economic, and health care indicators were collected as independent variables for these two periods. The rates of variation between periods were estimated for each variable. Multiple linear regression models were used to define the association between infant and perinatal mortality and their respective rate of variation with the former indicators. Mean familial income was the main predictive factor for infant and perinatal mortality in the first period but in the second period health care indicators were more relevant.

CONCLUSIONS

The reduction in Spanish infant and perinatal mortality over the period can be attributed mainly to the improvement in prenatal and neonatal health care in Spain in recent years, while economic factors seem less important.

[Adhesiveness in Neisseria meningitidis. A virulence factor?]

The role of adhesivity as a factor of virulence in cases of N. meningitidis has not yet been established. Unlike other bacteria in which the presence of adhesivity reflects an enhanced virulence, a high capacity of adherence is associated with a low virulence and invasive capacity in cases of meningococcus. In order to gain more insight into the knowledge of this phenomenon we have studied the adhesivity of 109 strains of N. meningitidis to human pharyngeal epithelial cells. Twenty nine out of the 109 strains were isolated from blood or spinal fluid of patients with meningococcal infection (meningitis or septicemia), whereas the remaining 80 strains were obtained from pharyngeal smears of healthy carriers. The adhesivity was measured as the number of meningococci adhered to 50 epithelial cells according to Craven's scale. Strains of healthy carriers showed a greater adhesivity than that of patients (p less than 0.001). The relevance of the pharyngeal area in the evaluation of the adhesive capacity is in accordance with the hypothesis that meningococcal adhesivity decreases when the microorganism crosses the pharyngeal epithelium. The results would support the concept that the virulence of N. meningitidis is related to its adhesiveness.