Syphilitic acute posterior placoid chorioretinitis in nonimmuno-compromised patients

PURPOSE

To describe the clinical and angiographic features of three cases of secondary syphilis in immunocompetent patients, which presented as acute posterior placoid chorioretinitis (APPC) to the ophthalmologist.

METHODS

Interventional case series. The aetiology of the APPC was confirmed by serology to be secondary syphilis. Optical coherence tomography, electrophysiology, fundus fluorescein, and indocyanine green (ICG) angiography were performed at presentation and after resolution. Appropriate treatment for secondary syphilis was instituted in each patient.

RESULTS

The clinical features, fundus fluorescein and ICG angiography, multifocal electroretinography (mfERG), and optical coherence tomography findings of APPC are described. All three patients had a satisfactory resolution of the APPC with improvement in visual acuity.

CONCLUSIONS

APPC in secondary syphilis can occur even in immunocompetent patients. A high index of suspicion is required for early diagnosis of this condition resulting in a good visual outcome with adequate treatment. mfERG and optical coherence tomography are useful in the diagnosis and follow-up of these patients.

Assessment of the environmental impact of artificial effluent lagoon in Jiayuguan City of China

An artificial effluent lagoon for storing wastewater were excavated in Jiayuguan City since 1994. As a part of a demonstration project of Sino-Australia cooperation, an assessment of the environmental impact of the lagoon was carried out. The assessment was based on field and laboratory tests and predictive model. The main impacts from the lagoon site are likely to be on the groundwater system, and, to a lesser extent, on ambient air quality in the vicinity. Currently it is expected that groundwater is being polluted with effluent from the effluent lagoon. Air pollution (odor nuisance) is mainly caused by untreated effluent in the irrigation channel. The impact of high total dissolved salt (TDS) on groundwater is likely to be significant in the long run if the lagoon is continuously used. There is, consequently, no likelihood of contamination of surface water system, particularly of the city water supply system, from infiltration of effluent at the lagoon.

The World Health Organization Health and Work Performance Questionnaire (HPQ)

This report describes the World Health Organization Health and Work Performance Questionnaire (HPQ), a self-report instrument designed to estimate the workplace costs of health problems in terms of reduced job performance, sickness absence, and work-related accidents-injuries. Calibration data are presented on the relationship between individual-level HPQ reports and archival measures of work performance and absenteeism obtained from employer archives in four groups: airline reservation agents (n = 441), customer service representatives (n = 505), automobile company executives (n = 554), and railroad engineers (n = 850). Good concordance is found between the HPQ and the archival measures in all four occupations. The paper closes with a brief discussion of the calibration methodology used to monetize HPQ reports and of future directions in substantive research based on the HPQ.

Underestimates of unintentional firearm fatalities: comparing Supplementary Homicide Report data with the National Vital Statistics System

OBJECTIVE

A growing body of evidence suggests that the nation's vital statistics system undercounts unintentional firearm deaths that are not self inflicted. This issue was examined by comparing how unintentional firearm injuries identified in police Supplementary Homicide Report (SHR) data were coded in the National Vital Statistics System.

METHODS

National Vital Statistics System data are based on death certificates and divide firearm fatalities into six subcategories: homicide, suicide, accident, legal intervention, war operations, and undetermined. SHRs are completed by local police departments as part of the FBI's Uniform Crime Reports program. The SHR divides homicides into two categories: "murder and non-negligent manslaughter" (type A) and "negligent manslaughter" (type B). Type B shooting deaths are those that are inflicted by another person and that a police investigation determined were inflicted unintentionally, as in a child killing a playmate after mistaking a gun for a toy. In 1997, the SHR classified 168 shooting victims this way. Using probabilistic matching, 140 of these victims were linked to their death certificate records.

RESULTS

Among the 140 linked cases, 75% were recorded on the death certificate as homicides and only 23% as accidents.

CONCLUSION

Official data from the National Vital Statistics System almost certainly undercount firearm accidents when the victim is shot by another person.

The effects of vigabatrin on electrophysiology and visual fields in epileptics: a controlled study with a discussion of possible mechanisms

PURPOSE

To compare the visual electrophysiology and visual fields of patients taking vigabatrin to those of a control group of epileptics on other anti-epileptic drugs (AEDs).

METHODS

Fourteen epileptics treated with vigabatrin and 10 control patients treated with other AEDs underwent ERG and EOG. Goldmann visual fields were performed and analysed using standard software to measure areas contained within I4e isopters.

RESULTS

The cone and rod b-waves of the ERG, the oscillatory potential amplitudes and Arden indices were reduced in vigabatrin-treated subjects and the oscillatory potentials delayed. The Arden indices were reduced due to an increased dark trough. The areas contained within the I4e isopter of vigabatrin treated subjects were reduced compared to the control group and these areas correlated well with oscillatory potential amplitudes and b-wave amplitudes in the vigabatrin group only.

CONCLUSIONS

The use of vigabatrin is associated with a reduction of the ERG cone b-wave amplitude and oscillatory potentials which correlates with visual field loss. The Arden ratio is reduced in subjects taking vigabatrin but may recover after cessation. However, visual loss may persist in the presence of a recovered EOG. These findings suggest further effects of the drug than those mediated by GABA receptors, and support the contention that the cause of the field loss may be at least in part due to retinal effects. Possible mechanisms are discussed.

A first comparison of the human multifocal visual evoked magnetic field and visual evoked potential

Our objectives were to determine the feasibility of recording reliable multifocal visual evoked magnetic fields (mfVEFs), to investigate the maximum stimulus eccentricity for which the mfVEF responses can be obtained, and to study how this changes with checksize (spatial frequency tuning). Using a checksize of 30', we recorded 8-channel pattern-onset mfVEFs three times to obtain responses from 19 channels located around the inion. Multifocal visual evoked potentials (mfVEPs) were recorded under the same conditions. Eccentricity changes with spatial frequency were studied using checksizes from 7.5' to 60'. We obtained, for the first time, reliable mfVEFs, and found they could be elicited from more peripheral stimulus elements than could mfVEPs. The larger the checksize, the greater the eccentricity reached.

Depression and work productivity: the comparative costs of treatment versus nontreatment

This article discusses the impact of depression on work productivity and the potential for improved work performance associated with effective treatment. We undertook a review of the literature by means of a computer search using the following key terms: cost of illness, work loss, sickness absence, productivity, performance, and disability. Published works were considered in four categories: (1) naturalistic cross-sectional studies that found greater self-reported work impairment among depressed workers; (2) naturalistic longitudinal studies that found a synchrony of change between depression and work impairment; (3) uncontrolled treatment studies that found reduced work impairment with successful treatment; and (4) controlled trials that usually, but not always, found greater reduction in work impairment among treated patients. Observational data suggest that productivity gains following effective depression treatment could far exceed direct treatment costs. Randomized effectiveness trials are needed before we can conclude definitively that depression treatment results in productivity improvements sufficient to offset direct treatment costs.

Electro-oculography, electroretinography, visual evoked potentials, and multifocal electroretinography in patients with vigabatrin-attributed visual field constriction

PURPOSE

Symptomatic visual field constriction thought to be associated with vigabatrin has been reported. The current study investigated the visual fields and visual electrophysiology of eight patients with known vigabatrin-attributed visual field loss, three of whom were reported previously. Six of the patients were no longer receiving vigabatrin.

METHODS

The central and peripheral fields were examined with the Humphrey Visual Field Analyzer. Full visual electrophysiology, including flash electroretinography (ERG), pattern electroretinography, multifocal ERG using the VERIS system, electro-oculography, and flash and pattern visual evoked potentials, was undertaken.

RESULTS

Seven patients showed marked visual field constriction with some sparing of the temporal visual field. The eighth exhibited concentric constriction. Most electrophysiological responses were usually just within normal limits; two patients had subnormal Arden electro-oculography indices; and one patient showed an abnormally delayed photopic b wave. However, five patients showed delayed 30-Hz flicker b waves, and seven patients showed delayed oscillatory potentials. Multifocal ERG showed abnormalities that sometimes correlated with the visual field appearance and confirmed that the deficit occurs at the retinal level.

CONCLUSION

Marked visual field constriction appears to be associated with vigabatrin therapy. The field defects and some electrophysiological abnormalities persist when vigabatrin therapy is withdrawn.

Cervical lymphadenitis due to non-tuberculous mycobacteria: surgical treatment and review

A retrospective study was carried out on 57 children, presenting with non-tuberculous mycobacterial (NTM) lymphadenitis of the head and neck, over a 12 year period. Cultures recovered 56 Mycobacterium avium-intracellulare (MAI), and one Mycobacterium kansasaii. Anti-mycobacterial agents were used in seven patients only. On the basis of the initial operation there were two groups. Group 1 (11 patients) had an excision, and Group 2 (46 patients) had incision and drainage (30 patients), incision and curettage (13 patients), or aspiration (three patients). There was no significant difference in the makeup of these two groups. However, Group 1 had significantly lower number of re-operations than Group 2, P<0.01, and achieved a significantly greater healing rate than Group 2, P<0.001. In Group 2 those who had an excision following failure of the first operation were significantly more likely to heal than those who did not, P<0. 005. Operative excision gives a lower rate of re-operation, and a higher rate of healing than other procedures. The treatment, natural history, clinical presentation, pathogenesis, and diagnosis of NTM cervical lymphadenitis are discussed.

The dose-effect relationship for morphine and vomiting after day-stay tonsillectomy in children

A dose-response curve for intravenous morphine and vomiting was investigated in children having day-stay tonsillectomy. A retrospective chart review was performed for the 164 children fulfilling the inclusion criteria. Morphine (mean 0.09 mg/kg SD 0.05) was used in 108 children in the perioperative period and a further 56 children were given no opioid. Fifty-five of these 164 children vomited and 20 children required an overnight stay in hospital because of vomiting. The probability of vomiting or overnight stay in hospital was related to morphine dose (by logistic regression). The overall probability of vomiting after morphine 0.1 mg/kg was 50% and the probability of admission for vomiting with this dose was 10%. Pharmacodynamic parameter estimates for postoperative vomiting were P0 (the baseline probability of vomiting, with no opioid) 0.115, Pmax (the maximal probability of vomiting due to morphine) 0.997, ED50 (morphine dose that induces an effect equivalent to 50% of the logit Pmax) 0.18 mg/kg. Parameter estimates for overnight stay because of vomiting after morphine administration were P0 0.038, Pmax 0.999, ED50 0.369 mg/kg. Satisfactory postoperative analgesia in children has been reported with morphine 0.05 to 0.15 mg/kg. Doses above 0.1 mg/kg are associated with a greater than 50% incidence of vomiting. Our data suggests that lower doses of morphine are associated with a decreased incidence of emesis after tonsillectomy in children.

On defining wisdom

Many gerontologists propose definitions of wisdom. Usually these are "empirical," as opposed to a-priori or "real" definitions. In this article we defend an a-priori definition of wisdom. We briefly explain a-priori and empirical definitions, and how they relate to each other in research. After rejecting two classical a-priori definitions of wisdom, we present and defend our own, and examine its ability to predict key findings of recent empirical studies. Finally, we describe some implications of our approach for future empirical studies of wisdom.

Depression in the workplace: effects on short-term disability

We analyzed data from two national surveys to estimate the short-term work disability associated with thirty-day major depression. Depressed workers were found to have between 1.5 and 3.2 more short-term work-disability days in a thirty-day period than other workers had, with a salary-equivalent productivity loss averaging between $182 and $395. These workplace costs are nearly as large as the direct costs of successful depression treatment, which suggests that encouraging depressed workers to obtain treatment might be cost-effective for some employers.

Guidelines for calibration of stimulus and recording parameters used in clinical electrophysiology of vision. Calibration Standard Committee of the International Society for Clinical Electrophysiology of Vision (ISCEV)

In order to perform a technically adequate clinical electrophysiological procedure it is necessary to calibrate the stimulating and recording equipment. Published standards for the electroretinogram (ERG), electro-oculogram (EOG), visual evoked potential (VEP), and guidelines for the Pattern ERG (PERG) specify stimulus and recording parameters. Yet, most commercial instruments do not provide the means for calibration of these parameters. The goal of this document is to provide guidelines for proper calibration of stimulus and recording equipment. The need for such guidelines is clear on both clinical and scientific grounds. Stimulus and amplifier characteristics have substantial effects on the peak latency and amplitude measurements that are commonly used in clinical electrophysiology. Many review articles on clinical electrophysiology emphasize the need for establishing norms for each laboratory as a function of age and gender rather than relying on published norms. However, if stimulus and recording parameters are not calibrated periodically, then these norms may actually be misleading due to changes in stimulus or recording conditions induced by aging of equipment or inadvertent change in settings. This document is divided into two major sections. The first is concerned with calibration of the visual stimulus. It begins with background technical information on the physics of light and its measurement. This is followed by protocols for measurement of the luminous intensity of flash stimuli and the mean luminance, contrast, and visual angle of pattern stimuli. The second section is concerned with calibration of electrophysiologic recording systems. It begins with a description of the characteristics of bioelectrical signals and their measurement. This is followed by protocols for measurement of electrode impedance and amplifier calibration. Although this document was prepared as guidelines for clinical electrophysiological testing, it should be noted that the techniques described are more generally applicable to studies which are dependent upon accurate measurement of luminance or electrophysiological signals.

Low- versus high-pressure irrigation techniques in Staphylococcus aureus-inoculated wounds

Current teaching emphasizes the importance of high-pressure (5 to 8 pounds per square inch [psi]) irrigation of traumatic wounds. The purpose of this study was to compare the irrigation efficacy, in an animal wound model, of the traditional higher-pressure, lower-volume (HPLV) syringe and catheter method of wound irrigation with a novel lower-pressure, higher-volume (LPHV) "port" method of irrigation. Experimental rat wounds were inoculated and incubated for 1 to 5 hours with a pathogenic strain of Staphylococcus aureus bacteria, then irrigated with one of the two methods. Irrigation times, mean irrigation pressures, and bacterial removal of the two techniques were compared. LPHV irrigation times were one third those of the HPLV. Mean irrigation pressures were 8.8 psi for HPLV and 1.6 psi for LPHV. HPLV and LPHV were found to be equally effective at washing out bacteria from the inoculated wounds at all times studied.

Performance of liquid-based, thin-layer cervical cytology: correlation with reference diagnoses and human papillomavirus testing

The performance of thin-layer cervical cytology with the use of ThinPrep (Cytyc Corporation, Boxborough, MA) was assessed by comparing the original independent diagnosis of ThinPrep slides and conventional smears prepared from 1780 split samples with the most abnormal diagnosis per patient on the basis of an independent pathologist's masked review and with the detection of cancer-associated types of human papillomavirus (HPV) DNA. Cases were selected on the basis of the original diagnoses to include all discordant pairs (those diagnosed as atypical squamous cells of undetermined significance or higher grade, n = 1017), all concordant abnormal pairs (n = 444), and a random 5% of concordant normal pairs (n = 319). In screening centers, thin-layer cytology detected 135 (70.3%) of 192 women diagnosed as having squamous epithelial lesions or a higher grade in the independent review, whereas locally read smears detected 91 (47.4%) of these patients (P < .001). In hospital-based cytology laboratories, thin-layer cytology detected 308 (86.3%) of 357 women diagnosed with SILs or a higher grade in the independent review, compared with 283 (79.3%) diagnosed with smears (P = .011). Cancer-associated types of HPV DNA were detected in a slightly higher proportion of women with smears diagnosed as SILs than in women with thin-layer cytology diagnosed as SILs, whereas the overall number of HPV-associated SILs diagnosed was higher with thin-layer cytology. These data suggest that the ThinPrep method detects a higher percentage of SILs as defined in a masked, independent review than do concurrently prepared smears and that diagnoses of SILs rendered with ThinPrep correlate with the detection of cancer-associated types of HPV.

Intravenous lactate prevents cerebral dysfunction during hypoglycaemia in insulin-dependent diabetes mellitus

1. Intravenous lactate prevents cerebral dysfunction during hypoglycaemia in healthy volunteers. This study examines whether this also occurs in insulin-dependent diabetes. Changes in four-choice reaction time, auditory brain stem response, and P300 latency were used as measures of cerebral function. 2. Ten subjects were studied twice at least 4 weeks apart. Blood glucose was maintained between 5 and 8 mmol/l for 1 h before starting a 60 m-unit min-1 m-2 stepped hyperinsulinaemic clamp, achieving blood glucose concentrations of 4.5, 3.3 and 2.5 mmol/l. At one visit, 40 mumol min-1 kg-1 sodium lactate was infused, and at the other, normal saline. Cerebral function was measured at each blood glucose concentration. 3. Blood lactate rose to 3.32 +/- 0.06 mmol/l during lactate infusion compared with 0.9 +/- 0.03 mmol/l during saline infusion. Compared with the results at 4.5 mmol/l there were no significant changes at 3.3 mmol/l in any measure of cerebral function at either visit. At 2.5 mmol/l a significant increase in reaction time and P300 latency occurred with saline [mean change 33.1 +/- 8.6 ms (P < 0.01) and 30.1 +/- 9.2 ms (P < 0.01) respectively] but not lactate [mean change -5.9 +/- 3.7 ms (P > 0.05) and -6 +/- 7.6 ms (P > 0.05) respectively]. No significant changes occurred in auditory brain stem response. The catecholamine response to hypoglycaemia was attenuated by lactate (P < 0.05 for adrenaline and noradrenaline). 4. Thus intravenous lactate prevents cerebral dysfunction during hypoglycaemia in insulin-dependent diabetes.

The effect of intravenous lactate on cerebral function during hypoglycaemia

Any factor which protects the brain against hypoglycaemia induced cerebral dysfunction could have important therapeutic implications for intensive insulin therapy. This study tested the hypothesis that intravenous lactate protects cerebral function during hypoglycaemia. Four choice reaction time, Auditory Brain Stem Response (ABR), and P300 latency were used as measures of cerebral function. Nine healthy volunteers (six female) underwent two stepped hyperinsulinaemic clamps at least 4 weeks apart, achieving blood glucose levels of 4.5, 3.3, and 2.5 mmol l-1. On one occasion 40 mumol kg-1 min-1 sodium lactate was infused, and on the other, normal saline. Cerebral function tests were measured at each glucose level. At 3.3 mmol l-1, there was a significant slowing of four choice reaction time with saline (p < 0.02) but not with lactate; no changes in P300 latency or ABR occurred on either occasion. At 2.5 mmol l-1 results from all three tests deteriorated significantly during saline infusion (p < 0.001 reaction time, p < 0.02 ABR and p < 0.05 P300), but not lactate. Lactate infusion was associated with a reduction in noradrenaline (p < 0.05), adrenaline (p < 0.05), and growth hormone (p < 0.02) responses at a glucose of 2.5 mmol l-1. These results support the hypothesis that intravenous lactate protects cerebral function during hypoglycaemia.

Pattern of utilization of rifabutin for prophylaxis of Mycobacterium avium complex among patients with advanced human immunodeficiency virus disease in a community setting

OBJECTIVE

To characterize the pattern of utilization, effectiveness, and safety profile of rifabutin for Mycobacterium avium complex (MAC) prophylaxis among individuals with advanced human immunodeficiency virus disease in a community setting.

METHODS

Individuals who, while registered in the provincial drug distribution program, had at least one CD4 count below 100 cells/mm3 for the period 1 May 1993 to 31 March 1994 were included. MAC diagnoses were identified through a record linkage with the mycobacterial reference laboratory of the Provincial Centre for Disease Control. In order to determine the occurrence of adverse events, a survey was sent in March 1994 to the 98 primary care physicians prescribing rifabutin prophylaxis in the province. We achieved 100% response rate to the survey.

RESULTS

During the study period 515 patients in our drug treatment program were eligible to receive MAC prophylaxis. Of these, 340 (66%) were being prescribed rifabutin as recommended by current guidelines. Rifabutin prophylaxis use was significantly associated with use of antiretroviral therapy. The product limit estimate of the cumulative incidence of MAC at 10 months was 13.0% among those receiving rifabutin prophylaxis. Diagnosis of MAC was significantly associated with a lower baseline CD4 count (cumulative incidence 7.1% and 18.1% for CD4 > or = 50 and < 50 cells/mm3, respectively, P = 0.01). A total of four cases of uveitis, eight cases of pseudo-jaundice, and five cases of arthralgia in 16 patients were identified by our survey.

CONCLUSION

Our data demonstrates that rifabutin prophylaxis of MAC is being used by approximately 66% of eligible individuals. Rifabutin use was associated with antiretroviral use, which may reflect individuals' attitudes towards medications. Our intention-to-treat analysis, with a 10 month cumulative MAC incidence of 13.0% among those receiving rifabutin prophylaxis, is in keeping with break-through rates previously reported in the context of clinical trials. Our results also support previous observations that the risk of MAC infection greatly increases at CD4 counts < 50 cells/mm3. Rifabutin prophylaxis was generally well-tolerated in our program.

The microbiology of chronic otitis media with effusion in a group of Auckland children

AIMS

To determine the microbiology of chronic otitis media with effusion in a group of Auckland children. To determine the antimicrobial sensitivities of isolated bacterial pathogens to commonly used antibiotics for this condition.

METHODS

A descriptive study recruiting subjects from otherwise well children with chronic otitis media with effusion having insertion of ventilation tubes at Starship Children's Health, Auckland. Tympanocentesis was performed, the middle ear aspirate cultured and antimicrobial sensitivities obtained.

RESULTS

Sixty seven children (11mo to 8yr) with chronic otitis media with effusion had tympanocentesis of 105 ears. 38/105 (36%) of the middle ear aspirate cultures were positive. Forty nine organisms were isolated with 10 ears having two or more different bacteria identified. Isolated were 17 Haemophilus influenzae (16 nontype b and 1 type b), 13 Moraxella catarrhalis, nine Streptococcus pneumoniae and 10 'others'. All S pneumoniae(9/9), most H influenzae(14/17) and no M catarrhalis(0/13) were sensitive to amoxycillin. More than 80% of subjects had either a sterile effusion or an organism sensitive to amoxycillin or cotrimoxazole.

CONCLUSIONS

Middle ear effusions were culture positive in a third of cases of chronic otitis media with effusion. The commonest organisms were H influenzae nontype b, M catarrhalis and S pneumoniae. This is similar to reports from other countries. Sensitivity data obtained supports the continued recommendation of amoxycillin or cotrimoxazole as first line therapy for the antimicrobial treatment of this condition.