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Biomedical subjects

R S Howard

Publications and source records attributed to R S Howard.

At least 55 records · Page 3Linked to original sources
PubMed1999

Accuracy of respiratory inductive plethysmography for the diagnosis of upper airway resistance syndrome.

OBJECTIVE: To determine the sensitivity and specificity of quantitative respiratory inductive plethysmography (RIP) compared with the "gold standard," nocturnal esophageal pressure (Pes) measurement, in the diagnosis of upper airway resistance syndrome (UARS) in adults. METHODS: Fourteen consecutive patients without obstructive sleep apnea and suspected of having UARS underwent simultaneous measurement of Pes with a catheter and standard nocturnal polysomnography along with RIP. UARS events (RERAs, respiratory effort-related arousals) were identified by observing crescendo changes in Pes with a Pes nadir < or = -12 cm H2O, followed by an arousal or microarousal. UARS was defined as > or = 10 RERAs per hour. For each patient, the ratio of peak inspiratory flow to mean inspiratory flow (PIFMF) measured by RIP was performed during quiet wakefulness and with 40 randomly selected breaths in the supine position for two conditions: stage 2 sleep, immediately prior to arousals in any sleep stage. The mean PIFMF (wake-sleep) was calculated for each condition. RESULTS: The sensitivities and specificities, respectively, of RIP to distinguish UARS patients from non-UARS patients are from stage 2 sleep (67%, 80%), immediately prior to arousals (100%, 100%). For breaths occurring immediately prior to arousals, the mean PIFMF (wake-sleep) is > or = 0.13 for UARS patients and < 0.13 for non-UARS patients. CONCLUSION: The PIFMF measured by RIP allows for the most accurate identification of UARS patients when breaths are selected for analysis immediately prior to arousals.

Adolescent↗
PubMed1999

The American College of Physicians' Resident Abstract Competition: success of U.S. military trainees.

Research is a central aspect of internal medicine (IM) training, and accreditation organizations require that residency programs show that their residents participate in scholarly activity. To better understand the research productivity and the quality of research conducted by military IM trainees, we reviewed the records of the American College of Physicians' Resident Abstract Competition from 1995 to 1997. This national competition is prestigious, blindly judged, and highly selective. We found that although military residents account for less than 2% of all U.S. and Canadian IM trainees, they author more than 11% of the abstracts selected for presentation (p < 0.001). We conclude that military IM residents are disproportionately represented compared with their civilian peers in an objective, national competitive forum. This is consistent with the higher scores on in-service examinations and higher board-certification pass rates for military IM residents.

Abstracting and Indexing↗
PubMed1999

Herpes virus infections occur frequently following treatment with fludarabine: results of a prospective natural history study.

We performed a prospective infectious natural history study of 21 patients with low-grade lymphoproliferative disorders receiving fludarabine as initial (n = 5) or salvage (n = 16) therapy. 12 (57%) of these patients developed herpes zoster (n = 9), herpes simplex I (n = 1) or herpes simplex II (n = 2) infections at a median of 8 (range 1-17) months following initiation of fludarabine, with 75% of these having completed therapy. All patients with herpes zoster developed severe post-herpetic neuralgia. Factors differentiating patients developing these infections included older age and low serum IgG or IgA. Based upon these prospective data, we conclude that herpes virus infections frequently occur following fludarabine treatment, necessitating aggressive patient education and new prophylactic strategies.

Aged↗
PubMed1999

The use of Western blotting as the confirmatory test for syphilis in patients with rheumatic disease.

OBJECTIVE: As a direct or indirect result of antiphospholipid antibody production, subjective laboratory interpretation, and false positive results, the common serologic tests for syphilis have been inherently inaccurate diagnostic tests in patients with systemic lupus erythematosus (SLE) and other autoimmune diseases. We assessed the diagnostic accuracy of syphilis testing in patients with SLE and other autoimmune diseases using the treponemal Western blot (TWB) as the gold standard. METHODS: A prospective cohort study carried out at a tertiary care medical center. We studied 107 patients with autoimmune disease, 50 with at least one positive serologic test for syphilis and 57 disease matched controls. Prior to enrollment all eligible patients underwent a clinical assessment performed by at least 2 rheumatologists to confirm a diagnosis of rheumatic disease. All subjects underwent serologic testing, in blinded fashion, for syphilis using the rapid plasma reagin test (RPR), Venereal Disease Research Laboratory test (VDRL), fluorescent treponemal antibody absorption test (FTA-ABS), and the TWB. RESULTS: Eighty-seven percent of the patients studied were female, the mean age was 46.5 years, and the most common diagnosis at the time of enrollment was SLE. Using the TWB as the gold standard diagnostic test for syphilis, the sensitivity, specificity, and positive predictive values for each syphilis test were calculated. The sensitivity and specificity for the RPR in patients with rheumatic disease was 62.5% (95% confidence interval 24.5 to 91.5%) and 91.9% (95% CI 84.2 to 96.2%), respectively. The sensitivity and specificity for the VDRL were 37.5% (95% CI 8.5 to 75.5%) and 89.9% (95% CI 81.8 to 94.8%), respectively. Confirmatory syphilis testing using the FTA-ABS showed a sensitivity of 100% (95% CI 68.6 to 100%) and a specificity of 67.7% (95% CI 57.4 to 76.5%). Eight patients tested positive for syphilis by Western blotting. For the FTA-ABS test, there was a significantly higher number of false positive results (n = 32) compared to false negative results (n = 0), p < 0.0005. CONCLUSION: The FTA-ABS is not an accurate confirmatory test for syphilis in patients with SLE and other autoimmune diseases. While a negative FTA-ABS may exclude syphilis infection in the majority of cases, a positive FTA-ABS test result cannot assuredly confirm syphilis infection in this population. Western blotting is an accurate confirmatory test for syphilis and may be necessary to unequivocally discern the immunological response of syphilis from that of an underlying autoimmune disease.

Blotting, Western↗
PubMed1998

Transient abnormalities in serum bilirubin and lactate dehydrogenase levels following red blood cell transfusions in adults.

BACKGROUND: The effect of transfusion of small amounts of packed red blood cells (PRBC) on serum chemistry values is not known. METHODS: We studied 73 adult patients without evidence of bleeding who received 2-unit PRBC transfusions. In study 1 (n=39), we examined multiple laboratory values pretransfusion and 15 minutes, 1 hour, 2 hours, and 24 hours posttransfusion. In study 2 (n=34), we examined changes in fractionated bilirubin, lactate dehydrogenase, and haptoglobin prior to and 1 hour following the transfusion. RESULTS: Total bilirubin increased from a median pretransfusion baseline of 0.7 mg/dL to 1.4 mg/dL shortly after transfusion (P <0.0005), and then returned to normal 24 hours later. Of the 36 patients with normal pretreatment total bilirubin levels, 17 (47%) became transiently abnormal. The lactate dehydrogenase level increased similarly 15 minutes after transfusion, but returned to baseline 24 hours later. The unconjugated bilirubin level increased from a median baseline pretransfusion value of 0.3 mg/dL to 1.1 mg/dL at 1 hour posttransfusion (P <0.0005). No significant changes were noted in conjugated bilirubin levels or haptoglobin concentration following transfusion. CONCLUSIONS: Transient increases in serum bilirubin and lactate dehydrogenase are seen following transfusion of PRBC. These data should be considered when interpreting laboratory values during the first few hours after a transfusion.

Adult↗
PubMed1998

Carotid cavernous fistula associated with persistent trigeminal artery: endovascular treatment using coil embolization.

Carotid-cavernous fistula (CCF) associated with persistent trigeminal artery (PTA) is a rare but important clinical entity. We present a case treated by microcoil embolization with preservation of internal carotid, PTA, and hasilar artery flow following embolization. A 62-year-old female developed pulsatile tinnitus followed by left eye proptosis and diplopia. Examination revealed a cranial nerve VI palsy and an objective bruit over the left orbit. Angiographic evaluation revealed a carotid cavernous fistula originating from a persistent trigeminal artery. Placement of a detachable balloon across the fistula site while preserving the PTA proved impossible, and the fistula was treated with microcoils following placement of a microcatheter across the fistula into the cavernous sinus. Complete closure of the fistula was followed by resolution of the patient's symptoms. Preservation of all major vessels including the PTA was accomplished through the use of coil embolization. Careful evaluation of the angiogram is necessary to identify PTA associated with a CCF. Previous reports have described treatment of CCF with PTA by surgical or balloon ocolusion, some involving sacrifice of the PTA. Examination of the relevant embryology and anatomy reveals, however, that occlusion of the PTA must be approached with caution due to potential supply to the posterior circulation.

Case Reports↗
PubMed1998

Status dystonicus: the syndrome and its management.

Patients with dystonic syndromes sometimes develop increasingly frequent and relentless episodes of devastating generalized dystonia which we call status dystonicus. Twelve cases of status dystonicus, of various underlying aetiologies, are presented. Possible precipitating factors were identified in only five cases: intercurrent infection (one); discontinuation of lithium (one) and tetrabenazine (one); and the introduction of clonazepam (two). Nine patients required mechanical ventilation and three others were sedated with intravenous chlormethiazole. Drug therapy used included benzhexol, tetrabenazine, pimozide, baclofen, chlorpromazine, haloperidol, carbamazepine and acetozolamide. Two patients underwent thalamotomies, one of whom improved. Two patients died, five returned to their pre-status dystonicus condition, two eventually made a full recovery and three were worse. Patients with status dystonicus should be managed on an intensive care unit as they may develop bulbar and respiratory complications which may require ventilation. Metabolic problems encountered can include rhabdomyolysis with acute renal failure. Drug therapy with benzhexol, tetrabenazine and pimozide or haloperidol may be beneficial in some cases.

Adolescent↗
PubMed1998

Early myoclonic status and outcome after cardiorespiratory arrest.

It has been suggested that early myoclonic status after cardiorespiratory arrest is an agonal event. Here we describe three cases who developed early myoclonic status during a coma after cardiorespiratory arrest due to acute asthma. As consciousness improved, each patient developed Lance-Adams type multifocal myoclonus, but the eventual outcome was satisfactory. Only one patient needed assistance to walk, and all three were self caring. One patient had persistent dyscalculia. Early myoclonic status is not necessarily an agonal event, particularly when it follows arrest due to acute asthma or asphyxia.

Adult↗
PubMed1998

Respiratory insufficiency due to high anterior cervical cord infarction.

OBJECTS AND METHODS: Respiratory dysfunction may occur as a result of lesions in the upper cervical spinal cord disturbing the descending pathways subserving automatic and volitional ventilatory control. Four patients are described who presented with acute respiratory insufficiency caused by infarction of the anterior portion of the upper cervical cord due to presumed anterior spinal artery occlusion. RESULTS: Two patients presented after respiratory arrests; they were ventilated and there was no automatic or volitional respiratory effort. Both had signs of an extensive anterior spinal cord lesion at the C2 level and this was confirmed by MRI. One patient presented with a C4 infarction and required ventilation for three months. Ventilatory recovery was characterised by the development of an automatic respiratory pattern. The fourth patient required ventilation for two months after infarction at the C3 level. On attempted weaning he had prolonged periods of hypoventilation and apnoea during inattention and sleep indicating impairment of automatic respiratory control. CONCLUSION: Infarction of the spinal cord at high cervical levels may be due to fibrocartilaginous embolism and involvement of the descending respiratory pathways may occur. Extensive lesions at C1/2 cause complete interruption of descending respiratory control leading to apnoea. Partial lesions at C3/4 cause selective interruption of automatic or voluntary pathways and give rise to characteristic respiratory patterns. The prognosis depends on the level and extent of the lesion.

Adult↗
PubMed1998

Treatment of premenstrual dysphoric disorder with sertraline during the luteal phase: a randomized, double-blind, placebo-controlled crossover trial.

BACKGROUND: The authors designed a randomized, double-blind, crossover study to assess the efficacy of sertraline in the treatment of premenstrual dysphoric disorder (PMDD) when given only during the luteal phase of the menstrual cycle. METHOD: Thirty-one subjects were selected for a 7-month study period that included an initial 2 months of screening, 2 months of treatment with placebo or sertraline, 1 washout month, and 2 months of crossover treatment with either placebo or sertraline. Eleven subjects completed the study. Symptoms were monitored with daily reports using the Calendar of Premenstrual Experience (COPE). For each study phase, premenstrual COPE scores (7 days prior to menses) were examined using repeated measures analysis of variance. Scores were logarithmically transformed. Comparison of baseline scores between the luteal and follicular phases was examined using the paired t test. RESULTS: Analysis of COPE results during the treatment periods of the luteal phase showed a significant treatment effect, with higher scores during the placebo cycles compared with the sertraline-treated cycles (p = .0052 behavioral, p = .014 physical). CONCLUSION: This study is the first to demonstrate a significant response to a serotonin selective reuptake inhibitor used only during the luteal phase. The authors point out the importance of this finding both in terms of economic cost of patients as well as how it may add to the growing understanding of the etiology of PMDD.

1-Naphthylamine↗
PubMed1997

Hodgkin's disease treated with neck radiation is associated with increased antibody-dependent cellular cytotoxicity against human extraocular muscle cells.

Patients with Hodgkin's disease have higher a prevalence of thyroid function abnormalities and, perhaps, orbitopathy than the general population, but the pathophysiology of this association and its relationship to Hodgkin's disease treatment remain unclear. We analyzed the frequency of thyroid function abnormalities, autoantibodies against thyroid antigens, and autoimmunity against extraocular muscle cell antigens by Western blot analyses and antibody-dependent cellular cytotoxicity (ADCC) assays in patients with Hodgkin's disease (n = 20) and controls (n = 10). Hodgkin's disease patients were subdivided into those treated with thyroidal external beam radiation therapy (XRT, n = 15) or chemotherapy (MOPP/ABVD, n = 5). The ADCC assay against extraocular muscle cells was increased in patients with Hodgkin's disease (5.5% vs. <1.0%, p = .026) when compared with controls. In addition, Hodgkin's disease patients treated with XRT (with or without chemotherapy) had significantly higher ADCC tests than controls (9.7% vs. <1.0%, p = .010), In contrast, ADCC assays were not different between Hodgkin's disease patients treated with chemotherapy alone and controls (<1.0% vs. <1.0%, p = .53). Hodgkin's patients treated with XRT had higher ADCC assays than those treated with chemotherapy alone (p = .087), although this difference did not achieve statistical significance. Serum measurements of antithyroid peroxidase (TPO) antibodies, antithyroglobulin (Tg) antibodies, thyroid binding inhibitory immunoglobulins (TBII), and thyroid stimulating immunoglobulin (TSI) were similar in all groups. Antibodies against the 64 kDa orbital antigen were detected in 1 patient and 1 control subject. Excluding patients already treated with L-thyroxine for hypothyroidism (n = 5), free T3, but not free T4, was lower in the Hodgkin's disease group than in controls (2.2 pg/mL vs. 2.7 pg/mL, p = .008). Thyrotropin (TSH) concentrations were not statistically different between these groups. In summary, these data show: (1) ADCC against human orbital muscle cells is increased in patients with Hodgkin's disease compared with controls: (2) these differences were noted among Hodgkin's disease patients treated with thyroidal XRT, with or without chemotherapy, and not among those patients treated with chemotherapy alone; and (3) no statistically significant differences in the frequency of thyroid autoantibodies were found. These data suggest that patients with Hodgkin's disease display altered antibody-dependent immune function toward extraocular muscle cells that may possibly be related to by XRT. Larger, prospective studies assessing thyroid and orbital-related immunologic abnormalities in Hodgkin's disease are warranted.

Adult↗
PubMed1997

Late functional deterioration following paralytic poliomyelitis.

Many patients with previous poliomyelitis develop 'post-polio syndrome' (PPS) in which late functional deterioration follows a period of relative stability. The frequency with which PPS can be attributed to clearly defined causes remains uncertain. We reviewed 283 newly-referred patients with previous poliomyelitis seen consecutively over a 4-year period; 239 patients developed symptoms of functional deterioration at a mean of 35 (5-65) years after the paralytic illness. Functional deterioration was associated with orthopaedic disorders in 170 cases, neurological disorders in 35, respiratory disorders in 19 and other disorders in 15. Progressive post-polio muscular atrophy was not observed. Functional deterioration following paralytic polio-myelitis is common, and associated with orthopaedic, neurological, respiratory and general medical factors which are potentially treatable.

Adult↗
PubMed1997

Longer term quality of life and outcome in stroke patients: is the Barthel index alone an adequate measure of outcome?

OBJECTIVES: To consider whether the Barthel Index alone provides sufficient information about the long term outcome of stroke. DESIGN: Cross sectional follow up study with a structured interview questionnaire and measures of impairment, disability, handicap, and general health. The scales used were the hospital anxiety and depression scale, mini mental state examination, Barthel index, modified Rankin scale, London handicap scale, Frenchay activities index, SF36, Nottingham health profile, life satisfaction index, and the caregiver strain index. SETTING: South east London. SUBJECTS: People, and their identified carers, resident in south east London in 1989-90 when they had their first in a life-time stroke aged under 75 years. INTERVENTIONS: Observational study. MAIN OUTCOME MEASURES: Comparison and correlation of the individual Barthel index scores with the scores on other outcome measures. RESULTS: One hundred and twenty three (42%) people were known to be alive, of whom 106 (86%) were interviewed. The median age was 71 years (range 34-79). The mean interval between the stroke and follow up was 4.9 years. The rank correlation coefficients between the Barthel and the different dimensions of the SF36 ranged from r = 0.217 (with the role emotional dimension) to r = 0.810 (with the physical functioning dimension); with the Nottingham health profile the range was r = -0.189 (with the sleep dimension, NS) to r = -0.840 (with the physical mobility dimension); with the hospital and anxiety scale depression component the coefficient was r = -0.563, with the life satisfaction index r = 0.361, with the London handicap scale r = 0.726 and with the Frenchay activities index r = 0.826. CONCLUSIONS: The place of the Barthel index as the standard outcome measure for populations of stroke patients is still justified for long term follow up, and may be a proxy for different outcome measures intended for the assessment of other domains.

Activities of Daily Living↗
PubMed1997

A long-term follow-up of stroke patients.

BACKGROUND AND PURPOSE: Two hundred ninety-one residents of southeast London, younger than 75 years, suffered their first stroke in 1989/1990. The objectives of this study were to determine the long-term outcome of this cohort of stroke patients in terms of impairment, disability, handicap, and quality of life and their use of services and prevention measures subsequent to their stroke. METHODS: The survivors and their identified caregivers were traced and completed a structured interview questionnaire that included the Barthel Index, modified Rankin Scale, Hospital Anxiety and Depression Scale (HAD), Mini-Mental State Examination, Frenchay Activities Index, and Caregiver Strain Index. RESULTS: One hundred twenty-three people (42%) were alive, of whom 106 were interviewed. The mean interval between the stroke and the long-term follow-up was 4.9 years. Thirty-one of the survivors (29%) were severely or moderately disabled, 39 (37%) were mildly disabled, and 36 (34%) were functionally independent. Of the 96 people who completed the HAD, 35 (36%) had scores suggesting that they were depressed or had borderline depression. The most likely nontherapy services to have been provided were chiropody and district nursing. Five people had received respite care. Of the 104 subjects for whom information about their home was available, 53 (51%) had had an adaptation. Seventy-five people (71%) had an aid or appliance. Sixty-five people (61%) were on aspirin, and an additional 14 (13%) were on warfarin. Fifty subjects (47%) identified a main caregiver. No one with a moderate or more severe disability was living at home without an identified caregiver. CONCLUSIONS: The levels of both health and social service provision are likely to be inadequate for this population. The use of prevention measures is encouraging. There is a clear need for a coordinated policy to guide assessment and management across sectors.

Aged↗