Protection against experimental echinococcosis by non-specifically stimulated peritoneal cells

Summary Infection of cotton rats with Echinococcus multilocularis or vaccination with BCG, or its cell walls, activates peritoneal cells to kill the protoscolices of the parasite in vitro and protects laboratory animals against the cestode. To determine whether other 'non-specific' stimuli would also protect against the parasite, cotton rat peritoneal cells were activated in vivo with PHA and transferred to recipients 3 days later. The recipients, controls and PHA-treated animals were then inoculated with the parasite; 3 days after inoculation other untreated infected animals received cells activated in vivo with PHA. PHA-activated cells, the PHA treatment itself and immunization with a homogenate of the parasite stimulated a leucocytosis and protected against infection by E. multilocularis; carrageenan abrogated protection in PHA-treated animals. The results of this study confirm that protection against echinococcosis can be induced non-specifically; these results suggest that immunity in hydatid disease may have an important component in the inflammatory reaction.     

Clinical Benefit of Dual Chamber Pacing in Hypertrophic Cardiomyopathy: A Case Report

This case study presents evidence that angioplasty and dual chamber pacing can be used as a therapeutic alternative to coronary artery bypass grafting and myectomy. The following case report describes this treatment option in a patient with hypertrophic Cardiomyopathy and ischemic heart disease who refused surgery. A severe coronary lesion was successfully treated with percutaneous transluminal coronary angioplasty (PTCA), Subsequent deterioration of the patient's clinical status occurred, yet a repeat heart catheterization revealed no angiographic changes from the PTCA. The left ventricular outflow gradient was 97 mmHg despite optimizing medical therapy. Temporary pacing leads were inserted and the patient was DDD paced at 70 ppm while measuring the LVgradient at varying A V intervals. Significant reduction of the outflow tract gradient occurred at all A V intervals tested. Although the pressure gradient decreased during VVI pacing, atrial contribution was necessary to achieve the desired hemodynamic benefit. A permanent DDDR pacemaker was implanted with satisfactory clinical results.     

DEATH AS A STIMULUS TO IMPROVING THE AFRICAN ENVIRONMENT FOR MORE HEALTHFUL LIVING

In D. Leviton's (1991) conception of horrendous death , a poorly managed environment can contribute to widespread mortality, and the deaths so caused can further create an environment for subsequent death. The African environment in particular is characterized by a number of "deathogenic" factors that must be understood and confronted by health educators committed to minimizing or eliminating the impact of horrendous death on the African continent. In this comment, the author argues that attention to characteristic but preventable forms of death in the African context can lead to greater public advocacy among African health educators, contributing to the physical and psychological wellbeing of the populations they serve.     

The Pediatric Corner

Thirty children less than 15 years of age with Crohn's disease are reported. The mean age of onset was nine years and five months. Delay in diagnosis may stem from the varying modes of presentation. The mean delay in diagnosis was two years. Chronic diarrhea and/or recurrent abdominal pain associated with extraintestinal manifestations, particularly abnormalities of growth and development suggests the possibility of Crohn's disease in the pediatric age group. Involvement of the terminal ileum occurred in 29 of the 30 patients. In addition, colonic disease occurred in 13 and jejunal involvement in one. Four patients presented with an acute onset of their disease. A favorable response to either medical or surgical therapy occurred in all four. Twenty-six patients had an insidious onset and tended to have a chronic course despite either medical and/or surgical therapy. Thirteen patients had an intestinal resection, with recurrence occurring in three from 1-4 years postoperatively. To date there has been one death.     

HYPOMAGNESAEMIA: STUDIES OF PARATHYROID HORMONE SECRETION AND FUNCTION

Nine patients with hypomagnesaemia have been studied. Six had magnesium deficiency secondary to malabsorption or diarrhoea and three had excessive urinary losses of magnesium. Hypocalcaemia was also present in eight. Parathyroid hormone (PTH) was measured using amino-terminal and carboxy-terminal specific immunoradiometric assays and also, in one patient, using a cytochemical bioassay. Amino-terminal PTH (N-PTH) varied directly with the concentration of magnesium; carboxy-terminal PTH (C-PTH) was raised in all patients. When magnesium was injected, both N-PTH and C-PTH rose regardless of the initial concentration, indicating that hypomagnesaemia was limiting PTH secretion. The clearance of endogenous PTH was measured in one patient, after injection of magnesium. Seven minutes after reaching its peak, C-PTH had fallen to 69% and N-PTH fell to 22% of its maximum values; the initial half life of N-PTH was less than 2 min. In the same study biologically active PTH (bio-PTH) disappeared rapidly with a half-time of disappearance of 1.2 min. Responsiveness to PTH was measured by the rise in plasma cyclic 3'5'-adenosine monophosphate (cAMP) following PTH injection. The rise in plasma cAMP was inversely related to the concentrations of magnesium and PTH at the time. It is suggested that the concentration of PTH rather than the degree of hypomagnesaemia is the most important factor determining the responsiveness of target tissues to PTH in magnesium deficiency.     

Renal Vein Thrombosis as the Major Cause of Renal Failure in Familial Mediterranean Fever

Eighteen out of 57 patients (31•6 per cent) suffering fromFamilial Mediterranean Fever (FMF) were found to have the nephroticsyndrome, histologically proven amyloidosis and progressiverenal failure. In 14 cases renal function deteriorated rapidlyafter the first appearance of significant proteinuria, and 12cases (66•7 per cent) required regular haemodialysis. Sevenof these patients, seen in the early stages of renal impairment,were subsequently diagnosed clinically as probably having developedrenal vein thrombosis. There was radiological proof of intrarenalor major renal vein occlusion in five which in one patient progressedto inferior vena cava obstruction. Treatment with heparin, plasminogenactivators and fibrinogenolytic agents was disappointing althoughrenal function has stabilized in one patient on long term oralanticoagulant therapy. It is suggested that renal vein thrombosisis common in FMF with renal amyloidosis and usually causes rapiddeterioration of function and irreversible renal failure requiringdialysis. Renal phlebography may delineate clot in the mainrenal veins or indicate areas of reduced blood flow due to thrombosesin intrarenal venules. Treatment is only partially satisfactorybut there is some evidence to suggest that renal phlebographyshould be undertaken promptly when renal function begins tofall followed by anticoagulant therapy to prevent further thromboemboliccomplications.