Delayed pressure urticaria, objective evaluation of a variable disease using a dermographometer and assessment of treatment using colchicine

A randomized double-blind placebo controlled trial of colchicine in the treatment of 13 patients with delayed pressure urticaria enabled us to assess some of the variables in this disorder. We have modified a previously described method of pressure testing using a calibrated dermographometer and shown a pressure induced papular dose response curve. Assessment of disease activity was based on the number of pressure weals which occurred, the size of delayed pressure induced papules using a dermographometer calibrated at 9.75 x 10(5) pascals for five separate time periods on the back and estimations of erythrocyte sedimentation rate and the acute phase protein levels. We have been unable to show a therapeutic effect using colchicine 0.5 mg bd for I week.     

Clinical Characteristics and Aetiological Classification of Insulin-dependent Diabetes in the Elderly

In a prospective study of 195 newly-diagnosed diabetic patientsaged 65 years or over, 80 (41.0 per cent) were treated initiallyby diet, 89 (45.6 per cent) by diet and oral hypoglycaemic agents,and 26 (13.3 per cent) by diet and insulin. Fifteen patients(7.7 per cent) died within a year of diagnosis. Of 26 patients treated with insulin, six died in the first year,14 were successfully transferred to diet and oral agent treatmentand six continued on insulin - two of whom failed a trial oforal agents, two showed only a temporary response and two receivedno trial. A further nine patients were taking insulin 12 monthsafter diagnosis because of no response (eight patients) or atransient response (one patient) only to oral agents. Age, percentage ideal body weight, history of acute onset, bloodglucose, glycosylated haemoglobin, and random C-peptide concentrationat diagnosis did not discriminate between patients requiringinsulin at 12 months and those successfully treated withoutinsulin. Patients who were insulin-dependent 12 months afterdiagnosis had an increased frequency of ketonuria at diagnosisand a previous medical history of endocrine disease. In insulin-dependent patients there was an increased frequencyof HLA DR3 but not DR4 and an increased frequency of thyroidmicrosomal and gastric parietal cell antibodies but not isletcell antibodies. It is concluded that elderly newly-diagnosed diabetic patientswho are treated at diagnosis with insulin are not necessarilyinsulin dependent and can be given a trial of oral agents withsafety. Elderly patients who are insulin-dependent within 12months of diagnosis have an increased frequency of HLA DR3 similarto young type 1 (insulin-dependent) diabetic patients but thereis no increased frequency of islet cell antibodies in this agegroup.     

Short-term decrease of skin-test sensitivity after rush desensitization in Hymenoptera venom hypersensitivity

Thirty-seven patients with a history of systemic anaphylactic stings were desensitized by the rush method. Patients were evaluated by skin testing twice, before and 6 weeks after desensitization. An additional control group of 10 patients, not yet desensitized, were tested for skin test technique reproducibility at 6-week intervals. Results were compared with IgE and IgG antibody levels, and with platelet reactivity towards specific Hymenoptera venom. Before desensitization, the maximum skin-test sensitivity was observed at 10(-5) micrograms venom/ml in 56% of patients and decreased to 10(-1) micrograms venom/ml after desensitization (48.6% of patients). Decrease of cutaneous tests was observed in 28/37 patients (75%) (P less than 0.001) and was not associated with significant variations of specific IgE or IgG antibody levels, but was correlated with the decrease of platelet reactivity (P less than 0.05). Conversely, variations of skin-test sensitivity in the control group was not significant.     

Glucosyltransferase activity in human in vivo formed enamel pellicle and in whole saliva

Abstract – Two hour in vivo formed enamel pellicle samples and paraffin wax-stimulated saliva samples were collected from 10 volunteers for analyses of glucosyltransferase activity (GTF). GTF activity was recorded by monitoring incorporation of radioactivity from ¹⁴C-glucose labeled sucrose into glucan. Pellicle and saliva samples from all 10 subjects demonstrated GTF activity. The GTF activity in the pellicle samples was highest in subjects, with high GTF activity-producing adhesive glucan in saliva.     

Cesarean Section Prophylaxis: Comparison of Two Doses With Three Doses of Mezlocillin

ABSTRACT: A prospective randomized double-blind comparison of two doses, with three doses of mezlocillin for nonelective cesarean section prophylaxis was performed. One hundred seven (107) patients were evaluated. Mezlocillin (4 g) was given post-cord clamping and then at 4-h intervals for a total of two doses or three doses. The incidence of febrile morbidity was lower in the three-dose group (2 of 46, 4%) than the two-dose group (14 of 61, 23%) (P<0.02). However, the incidence of infectious morbidity was not different between the three-dose group (3 of 46, 7%) and the two-dose group (10 of 61, 16%), and the incidence of endomyometritis was similar in the two groups (6.5% vs 9.8%). Among failures of prophylaxis there were no differences compared to successes in the number of potential commensals or potential pathogens cultured from amniotic fluid. However, the proportion of failures among patients with both commensals and potential pathogens isolated (10/58) was significantly greater than among patients with none or only commensals isolated (1/37) (P<0.03). We found mezlocillin to be an effective agent for perioperative cesarean section prophylaxis with two doses as effective as three doses. The presence of clinically important organisms in the amniotic fluid at the time of operation typified patients with postoperative infectious complications despite perioperative prophylaxis.     

The Impact of Pulse Generator Longevity on the Long-Term Costs of Cardiac Pacing

The long-term costs of cardiac pacing include the device costs, the procedural costs, the follow-up costs, and the replacement costs. At present, there is significant variability in the efficiencies of the integrated circuits and the total battery capacity among different pulse generators that will influence replacement rates over time. Accordingly, we compared the influence of pulse generator longevity on the long-term costs of pacing. The longevity of pulse generators was calculated based on the electrical characteristics of the device and the percentage of time the patient is paced. Replacement rates of pulse generators were estimated for our patient population over a 20-year period, based on patient survival and pulse generator longevity. The costs of pacing over this 20-year follow-up period were then calculated. The longevity of DDDR devices presently implanted in the United States ranges from 8–14 years, assuming that patients are paced 50% of the time. Replacement rates in this population over a 20-year follow-up period were calculated to range from 0.34–0.66, and the total costs of pacing would range from $11,898–14,900 per patient. The longevity of SSIR devices ranges from 7–20 years, assuming that patients are paced 50% of the time. Replacement rates were calculated over the 20-year follow-up period to range from 0.20–0.84, and the total costs of VVIR pacing would range from $8,331–13,286. Based on the proportion of pulse generator models implanted in patients in the United States, the maximum cost differential to the health care system is approximately $424 million/year comparing the devices with the shortest and greatest longevities. Thus, pulse generator longevity may significantly influence the long-term costs of pacing. Patient survival and pulse generator system longevity should be considered when selecting the appropriate pacing system for the individual patient.     

Propafenone-Induced Torsade de Pointes: Cross-Reactivity with Quinidine

A 77-year-oid/emale with new onset atrial fibrillation occurring in the absence of structural heart disease developed torsade de pointes during therapy with quinidine bisulfate 500 mg orally every 8 hours. Ten days after quinidine therapy had been discontinued she developed torsade de pointes while receiving propafenone 300 mg orally every 8 hours. This case demonstrates that propafenone may be associated with torsade de pointes and suggests a cross-reactivity between this effect and prior occurrence of torsade de pointes on Class IA antiarrhythmic drug therapy.     

Modification of Atrioventricular Conduction Using a Combined Laser-Electrode Catheter

Ablation of the AV junction is an accepted technique for the management of selected supraventricular tachyarrhythmias. Radiofrequency ablation appears to be safe and effective for AV junction ablation in most patients, but the need for firm tissue contact may make it less effective for ventricular tachycardia and certain ectopic atrial tachycardias. Laser energy can also be delivered through a catheter, and thus it may be an attractive alternative energy source for ablation. A new laser-electrode catheter was developed for modification of conduction through the AV node as a model for ablation of an arrhythmia substrate. A window for delivery of continuous-wave Nd:YAG laser energy was placed between the two electrodes of a bipolar electrode catheter. In vitro studies using a matrix of power versus time were performed to determine the energy that would create lesions of the appropriate size in vivo. Using this information, advanced AV block was successfully created in 16 of 17 dogs (94%) with the laser-electrode catheter. Advanced AV block was successfully created in all four dogs in the chronic study, and it persisted for 1-24 weeks of follow-up until sacrifice of the animals. Histologic examination demonstrated discrete thermal damage at the AV junction with no instances of septal perforation in the acute studies or progressive necrosis in chronically maintained dogs. Advanced AV block may be produced consistently and safely in dogs using a combined laser-electrode catheter.     

Ambulatory Electrocardiography for the Detection of Pacemaker Lead Failure

The suboptimal performance of some polyurethane bipolar pacing leads has highlighted concern about the optimal method of monitoring pacemaker lead performance. Since the manifestations of premature lead failure may be initially intermittent, we hypothesized that ambulatory electrocardiography (AECG) would be a more sensitive tool for the detection of pacing lead failure compared to increased pacemaker clinic surveillance. Since the Medtronic safety alerts on the 4012, 4082, and 4004 leads, we have followed 261 patients by serial AECG and 165 patients by increased pacemaker clinic surveillance. Lead failures were identified in 75 patients: 68 in the AECG group (31 %) and 7 in the clinic group (4%, P < 0.001). Repeat AECG confirmed the lead failure in 38 (97%) of 39 patients in which it could be done. Pacing lead failure documented by AECG could be confirmed by a subsequent clinic assessment in only 15 (25%) of 60 patients evaluated (P < 0.001). The actuarial survival of the 4012 lead was significantly lower in the AECG group compared to the clinic group (56% vs 87% survival at 8 years, P < 0.002). Similar trends were observed for the 4082 and 4004 leads. AECG is a more sensitive method of surveillance for pacemaker lead function compared to pacemaker clinic assessment. AECG should be incorporated into the routine follow-up of pacemaker patients. (PAGE 1997; 20[Pt. I]:127 4-1282)     

Effect of Concomitantly Administered Drugs on the Control of Long Term Anticoagulant Therapy

The stability of control of long term anticoagulant therapywas studied in a group of 277 patients with respect to druginteractions. Increased instability (changes of dose/month oftherapy) was related to the number of concomitant drugs takenirrespective of, and in addition to, known specific interactions.Fluctuating cardiac status in patients requiring digoxin anddiuretic therapy was a major factor in stabilizing anticoagulantcontrol.