Research committee

The JCAH move to evaluate clinical outcomes as part of its ongoing accreditation process has significant implications for infection control, APIC, and research. Through a concerted, progressive plan to address this issue, APIC can be a pathfinder in helping to prepare its members for this change. A proactive approach to both continued input into the process and the initiation of research to establish the groundwork are clearly indicated.     

Usefulness of Upstroke Time per Cardiac Cycle for Cardiovascular and All-Cause Mortality Prediction in Patients with Normal Ankle-Brachial Index

Aim: Abnormal ankle-brachial index (ABI) is regarded as peripheral artery disease and can be used to predict cardiovascular (CV) outcomes. However, the usefulness of ABI for the prediction of CV outcome in patients with normal ABI is limited. Upstroke time per cardiac cycle (UTCC) is recently reported to be associated with mortality in patients with acute myocardial infarction and the elderly. Therefore, we aimed to evaluate UTCC, left ventricular ejection fraction (LVEF), brachial-ankle pulse wave velocity (baPWV), and ABI for the prediction of mortality in patients with normal ABI. Methods: Patients arranged for echocardiographic examinations were enrolled, and 1076 patients with normal ABI were included. ABI, baPWV, and UTCC were measured by an ABI-form device. Results: The median follow-up to mortality was 95 months. There were 88 CV and 244 all-cause deaths. After multivariate analysis, UTCC was associated with increased CV and all-cause mortality ( P ≤ 0.004). Age, diabetes, heart failure, left ventricular hypertrophy, baPWV, and LVEF were also independent predictors of CV and all-cause mortality, but ABI was not. Furthermore, UTCC had a better additive predictive value than ABI, baPWV, and LVEF for CV mortality ( P ≤ 0.012). It also had a better additive predictive value than ABI and LVEF for all-cause mortality ( P ≤ 0.013). Conclusions: UTCC is an independent predictor for CV and all-cause mortality in patients with normal ABI. It also has a better additive predictive value of CV and all-cause mortality than ABI and LVEF. Therefore, UTCC is a simple, novel, and useful parameter for identifying high-risk patients with normal ABI.     

Are lasers superior to lights in the photoepilation of Fitzpatrick V and VI skin types? – A comparison between Nd:YAG laser and intense pulsed light

Background and objectives: There are no large volume comparative studies available to compare the efficacy of lasers over lights for hair removal in Fitzpatrick V and VI skin types. This study is designed to compare the efficacy of Nd:YAG laser versus IPL in the darker skin types. Study design/materials and methods: Thirty-nine patients included in Group-1 were treated with Nd:YAG and 31 in Group-2 with IPL. Both groups received 5 sessions of treatment. The hair counts were assessed using digital photography and manual counting method before and after treatment and the results were analysed. Patient satisfaction scores and pain scores were recorded in each session and compared. Results: Mean hair reduction in the IPL group was 25.70 and Nd:YAG group was 24.12 (95% CI). In the Nd:YAG group, 59% of subjects had burning sensation while the figure was 32.3% in IPL group. Burning was less in IPL group (p < 0.023). There were no statistically significant differences noticed regarding hyperpigmentation in both the groups (p < 0.115). Conclusion: Both Nd:YAG and IPL are equally effective for epilation of the darker skin types. Nd:YAG is associated with mild burning sensation in a significant number of patients. Patient satisfaction scores were comparable in both the groups.     

Histopathologic and Microbiologic Aspects of Ventilator-associated Pneumonia

Background: The relationship between microbiology and histology in patients with ventilator-associated pneumonia has been sparsely described.

Methods: Twenty-five patients who died in the intensive care unit after their lungs had been mechanically ventilated for 72 h were studied. Twenty of the 25 died with clinical suspicion of pulmonary infection. A total of 375 immediate postmortem pulmonary biopsies were obtained after death and processed for quantitative microbiology and histology. Four evolutionary stages of pneumonia were defined: early, intermediate, advanced, and resolution.

Results: At least one specimen with histologic evidence of pneumonia was found in all but two patients (92%). Histologic pneumonia was a widespread and frequent process (46% of biopsies examined) involving predominantly the lower lobes (55% of all biopsies with pneumonia) and showing different histopathologic stages of progression coexisting in the same lung lobes. Lung cultures were frequently polymicrobial (149 of 375, 40% of the pulmonary biopsy cultures, and 20 of 25, 80% of the cases) and not always yielding the same pathogen (19 microorganisms) when comparing one lung to the other. Histopathology and microbiologic biopsy cultures showed a weak relationship (28% and 49% of species had counts greater or equal to 103 cfu/g in samples without pneumonia from patients with and without prior antibiotic treatment, respectively). Histopathologic evolutionary stages were not associated with any differences in quantitative culture results of pulmonary biopsies, independently of prior administration of antibiotics. Higher bacterial concentrations of biopsy cultures were associated with the absence of prior antibiotic treatment.     

Experimental Lead Neuropathy: Ultrastructural And Molecular Changes In The Rat Sciatic Nerve

Experimental lead intoxication is an important model for the study of cellular and molecular mechanisms of segmental demyelination in peripheral nerve. In this report we have compared pathological changes with the molecular and immunohistochemical expression of the proteins of compact and non-compact myelin in the demyelinating neuropathy induced in Sprague-Dawley rats after chronic administration (3 and 6 months) of lead acetate in drinking water. All the rats underwent the neurophysiological determination of the conduction velocity in the tail nerve at baseline and 3, 4.5 and 6 months after the beginning of the lead acetate administration. At the end of the treatment period the rats were sacrificed and sciatic nerve specimens were obtained. The neurophysiological study demonstrated a significant decrease in the nerve conduction velocity, which was already evident at the first determination (3 months) and persisted along the entire experiment. The neurophysiological results were in agreement with the pathological observations performed in the sciatic nerve, where several large demyelinated fibers were observed in the lead-intoxicated rats. Northern and Western blot analysis demonstrated that steady state mRNA and protein levels for P0, MBP, PMP22 and PLP were not changed comparing treated and control rats. Immunohistochemistry on teased fibers revealed that those proteins were distributed in areas of compact myelin along the internodes. In control fibers, as expected, MAG was found in the periaxonal cytoplasm, at nodes of Ranvier, and in the Schmidt-Lanterman incisures. In lead neuropathy, MAG was still limited to discrete regions, but the intensity of staining was reduced, in accordance with changes of paranodal structures. Immunohistochemical localization of other proteins of non-compacted myelin, including connexin-32, E-cadherin and β-catenin was also examined. Our data further suggest that chronic lead intoxication in the rat produces segmental demyelination due primarily to Schwann cell dysfunction.     

Update on uveomeningoencephalitides

PURPOSE OF REVIEW: Uveomeningoencephalitides, commonly known as Vogt-Koyanagi-Harada (VKH) disease, are characterized by chronic bilateral granulomatous panuveitis involving the central nervous, auditory and integumentary systems. Visual prognosis is generally favourable, but outcomes in patients with VKH disease may vary. Also, the treatment of choice differs in different parts of the world. This review addresses the literature on the possible pathogenesis, diagnosis and treatment of this disorder. RECENT FINDINGS: Atypical presentations of VKH disease, as well as those associated with interferon-alpha therapy, have been reported. Most reports suggest an association with autoimmunity. The diagnostic criteria were revised by the International Workshop on VKH in 1999, allowing for the presence of different ocular findings in the early and late stages of the disease. New techniques have also been developed to aid in the rapid diagnosis of VKH disease and evaluation of treatment. Different routes of administration of corticosteroid and adjuvant therapy were tried, with positive results. SUMMARY: Although the pathogenesis of VKH disease is uncertain and antigen-specific treatment strategies have not yet been developed, reports increasingly suggest an autoimmune nature for uveomeningoencephalitides. Currently, systemic corticosteroid therapy remains the standard initial treatment. Different routes of administration are used to reduce the frequency of side effects of systemic corticosteroids, and there are various adjuvant therapies. With the aid of modern equipment, early diagnosis and prompt and appropriate treatment, resulting in better visual outcomes, can be anticipated. A large-scale, multinational, prospective study is warranted to determine the optimal initial therapy.     

BioVision: an application for the automated image analysis of histological sections

We describe a computer application, "BioVision", that can be trained to quickly and effectively classify and quantify user definable histological objects (e.g., senile plaques, neurofibrillary tangles) within single or double-labeled immunocytochemically stained sections. For a given image population, BioVision is interactively trained (in Independent User Mode) by an investigator to perform the desired classifications. This training yields a statistical model of the different types of objects occurring in the target image population. The resulting model can then be used (in Automated User Mode) to classify all objects in any image or images from the target population. BioVision simplifies the quantification of complex visual objects and improves inter-rater reliability. The program accomplishes classification in two major stages: pixel classification and blob classification. In pixel classification, each pixel is assigned to one of some number of substance classes, based on its chromatic properties and local context, reflecting basic histological distinctions of interest. In the blob classification phase, the image's pixels are first partitioned into "blobs": maximal connected sets of pixels assigned to the same substance class. Then, based on its size, shape, textural and contextual properties, each blob is assigned to a histological object class. A Bayesian classifier is used in each of the pixel and blob classification stages. We report several tests of BioVision. First, we applied BioVision to classify senile plaques and neurofibrillary tangles in several test cases of Alzheimer's brain immunostained for beta-amyloid and PHF-tau and compared the results to those produced by experienced investigators. BioVision was trained to classify Plaque-type blobs as either plaques or plaque-type nonentities, and tangle-type blobs as either tangles or tangle-type nonentities. BioVision classified the objects with an accuracy comparable to the trained investigator. Next, we applied BioVision to the task of counting all the tangles in hippocampal images from 22 Alzheimer's disease (AD) cases selected to span a broad range of dementia levels from the tissue repository of UC Irvine's Center for the study of Brain Aging and Dementia. The tangle counts produced by BioVision proved to be significantly better predictors of the cases' adjusted MMSE scores than any of tangle load, age at death, post mortem interval or the interval between the last MMSE score and death.     

Balancing high accrual and ethical recruitment in paediatric oncology: a qualitative study of the 'look and feel' of clinical trial discussions

Background  

High accrual to clinical trials enables new treatment strategies to be tested rapidly, accurately and with generalisability. Ethical standards also must be high so that participation is voluntary and informed. However, this can be difficult to achieve in trials with complex designs and in those which are closely embedded in clinical practice. Optimal recruitment requires a balance of both ethical and accrual considerations. In the context of a trial of stratified treatments for children with acute lymphoblastic leukaemia (UKALL2003) we examined how recruitment looked to an observer and how it felt to the parents, to identify how doctors' communication could promote or inhibit optimal recruitment.