ABSTRACTS

thrombocytopenia, HTLV-III infection

Thrombocytopenia as the presenting manifestat ion of human T.lymphotropic virus type III infection in infants Saulsbury FT, Boyle R J, Wykoff RF, et al J Pediatr 109:30-34 Jul 1986

A retrospective review of three infants in whom throm- bocytopenia was the presenting manifestation of HTLV-III infection was presented. All infants were born since 1982 and had received multiple blood transfusions in the neo- natal period. Each of the three infants, who were between 8 and 9 months of age, presented with thrombocytopenia. Studies revealed evidence of immune medicated platelet de- struction. Two infants had serum antibody to platelets and elevated platelet-associated immunoglobulin G. All three had abundant megakaryocytes on bone marrow examina- tion, and all three responded to a course of corticosteroids. Serum antibody to the HTLV-III virus was present in all in- fants. The mothers of these children had no known risk factors for HTLV-III infection and were seronegative on test- ing. The etiology of these infections is assumed to be from blood transfusions and the cause of the thrombocytopenia secondary to HTLV-III infection.

Pamela Downey, MD

hypertension, verapamil vs propranolol

A comparison of verapamil and propranolol for the initial t rea tment of hypertension Cubeddu LX, Aranda J, Singh B, et al JAMA 256:2214-2221 ©ct 1986

This study compared the use of verapamil with propran- olol in the monotherapy treatment of essential hyperten- sion. One hundred nineteen patients were studied in a double-blind fashion for a total of four weeks. No signifi- cant difference was found after two weeks; however, ve- rapamil was shown to reduce blood pressure significantly more than propranolol during the last two weeks of the study. At the end of therapy, 73% of those receiving ve- rapamil were normotensive (diastolic blood pressure < 90) as compared with 46% on propranolol (P < .01). The effects of propranolol were significantly greater in whites than in blacks (P = .02). There was no statistical difference in blood pressure lowering between blacks and whites in the ve- rapamil group. Twenty-two per cent of the propranolol group experienced a rise in systolic blood pressure com- pared with 2% of the verapamil subjects. No statistical dif- ference was found in side effects in the two groups. Ve- rapamil did increase the PR interval by 11 ms (P = .04},

compared with no significant increase from propranolol. It was concluded that, in the short term studied, verapamil was more efficacious than propranolol in lowering blood pressure.

Mark W Elliott, MD

heart block

The natural history of primary f irst-degree atr ioventr icular heart block Mymin D, Mathewson FAL, Tate RB, et al N Engl J Med 315:1183-1187 Nov 1986

The natural history of primary first-degree heart block was studied by examining life insurance records of 3,983 men recorded during a 30-year period. An abnormal PR in- terval was defined as greater than or equal to 0.22 seconds. Overall, 176 cases of primary first-degree heart block were found. Fifty-two cases were present at the study's start, and 124 cases developed during the study period. The average age of diagnosis was about 41 years. No association was found between developing first-degree heart block and smoking history, body-mass index, blood pressure, or child- hood history of scarlet fever, rheumatic fever, or diphtheria. Morbidity and mortality were not related to the PR interval. Among the men who entered the study with first-degree heart block, only one went on to a higher degree of block. individuals who developed a prolonged PR interval during the study did not progress to higher degrees of block. The PR interval did not change by more than 0.04 seconds for the vast majority throughout the 30 years. It was concluded that primary first-degree heart block is a benign condition in which the PR interval increases only slightly with age.

John Neufeld, MD

alcohol, driver injury

The potentiat ing ef fects of alcohol on driver injury Waller PF, Stewart JR, Hansen AR, et al JAMA 256:1461-1466 Sep 1986

It is widely believed that alcohol may protect from injury in that the drunk can "roll with the punches." Data on 1,136,507 drivers involved in single- or two-vehicle crashes in North Carolina from 1979 through 1983 were compiled to assess the relationship of driver injury to alcohol. Vari- ables of analysis included accident type, accident speed, car weight, driver belt use, vehicle deformation, and whether the driver was killed or seriously injured. Results of data for unrestrained drivers while considenng only accident type and vehicle deformation show alcohol-involved drivers were

176/130 Annals of Emergency Medicine 16:1 January 1987