Famotidine in the treatment of acute urticaria.

Recent studies suggest that histamine H2-receptor antagonists may be useful in the treatment of urticaria. This study was conducted to determine whether famotidine, a H2 antagonist, is effective in the treatment of acute urticaria and compare its effect with that of the H1 antagonist diphenhydramine. In this prospective, double-blind, controlled trial, 25 patients with urticaria of less than 72 h duration were randomized to receive a single dose of either famotidine 20 mg i.m. or diphenhydramine 50 mg i.m. Prior to treatment and 30 min after treatment, patients rated pruritus and sedation using visual analogue scales, while physicians evaluated intensity of urticaria and percentage of body surface area involved by urticaria. Famotidine was found to reduce pruritus associated with acute urticaria, intensity of urticaria, and body surface area affected by urticaria without causing sedation. Famotidine was comparable to diphenhydramine in efficacy; however, there was a (nonsignificant) trend for diphenhydramine to be more effective than famotidine in the treatment of pruritus, and for famotidine to be more effective in the reduction of surface area of involvement. It is concluded that famotidine merits further investigation as a potential medication for treatment of urticaria.

Detection of ureteral calculi in patients with suspected renal colic: value of reformatted noncontrast helical CT.

OBJECTIVE: The purpose of this study was to determine the value of reformatted noncontrast helical CT in patients with suspected renal colic. We hoped to determine whether this technique might create images acceptable to both radiologists and clinicians and replace our current protocol of sonography and abdominal plain film. SUBJECTS AND METHODS: Thirty-four consecutive patients with signs and symptoms of renal colic were imaged with both noncontrast helical CT and a combination of plain film of the abdomen and renal sonography. Reformatting of the helical CT data was performed on a workstation to create a variety of reformatted displays. The correlative studies were interpreted by separate blinded observers. Clinical data, including the presence of hematuria and the documentation of stone passage or removal, were recorded. RESULTS: Findings on 18 CT examinations were interpreted as positive for the presence of ureteral calculi; 16 of these cases were determined to be true positives on the basis of later-documented passage of a calculus. Thirteen of the 16 cases proved to be positive were interpreted as positive for renal calculi using the combination of abdominal plain film and renal sonography. The most useful CT reformatting technique was curved planar reformatting of the ureters to determine whether a ureteral calculus was present. CONCLUSION: In this study, noncontrast helical CT was a rapid and accurate method for determining the presence of ureteral calculi causing renal colic. The reformatted views produced images similar in appearance to excretory urograms, aiding greatly in communicating with clinicians. Limitations on the technique include the time and equipment necessary for reformatting and the suboptimal quality of reformatted images when little retroperitoneal fat is present.

Development of ventricular fibrillation after intravenous calcium chloride administration in a patient with supraventricular tachycardia.

The i.v. administration of calcium before or shortly after treatment of supraventricular tachycardia with verapamil has been suggested to counteract a hypotensive response to verapamil. We discuss the case of a patient who presented to the emergency department with an accelerated wide-complex tachycardia and minimal symptoms. Immediately after i.v. administration, of 1 g calcium chloride as pretreatment for verapamil administration, ventricular fibrillation developed. Emergency physicians should be aware of potential dangers after the administration of i.v. calcium preparations when trying to prevent known hypotensive side effects of i.v. verapamil administration.

The prevalence of hepatitis B serologic markers in suburban paramedics.

Urban emergency medical services personnel have documented hepatitis B virus (HBV) seropositivity rates ranging from 0.6% to 25%. We studied 85 suburban paramedics for Hepatitis B serologic markers. All paramedics answered a questionnaire describing age, race, duration of employment, known hepatitis exposure, blood transfusions, gamma globulin injections, and Hepatitis B vaccination. HBV surface antibodies (Anti-HBs) were present in 6/85 (7.1%) paramedics of whom one (1.2%) had reactive HBV core antibodies (Anti-HBc). No paramedic had HBV surface antigen (HBsAg). Seropositivity was not associated with duration of employment, or exposure to a patient with either jaundice (28.2%) or confirmed hepatitis B (20.0%) within the six months prior to testing. The 7.1% prevalence of HBV markers found in this group of suburban paramedics is intermediate between previously reported rates for urban paramedics. We conclude that prehospital personnel do not constitute a homogenous occupational category at risk for hepatitis B infection.