Days Of Oral Therapy Research Articles

Renal effects of calcium channel blockers in vivo

Daily output of urine was measured in three groups of five rabbits each, before and during seven days of oral therapy with nifedipine, verapamil and diltiazem. All the drugs caused significant ( P < 0.001) increases in mean daily output. All the drugs decreased levels of serum sodium but serum potassium levels were lowered only by diltiazem. Inhibition of tubular transport appears to be the important mechanism.

Acute and chronic hemodynamic effects of nicardipine hydrochloride in patients with heart failure

Acute and chronic hemodynamic effects at rest and during exercise of a new dihydropyridine calcium antagonist, nicardipine hydrochloride, were studied in 10 patients with chronic heart failure. Acute intravenous administration of nicardipine resulted in a significant decrease in arterial blood pressure, systemic vascular resistance, and pulmonary capillary wedge pressure. There was a significant increase in cardiac index, stroke volume index, and the left ventricular stroke work index. Cardiac index measured at peak exercise increased significantly when compared with the cardiac index obtained at peak exercise before the infusion. After 9 days of continuous therapy with nicardipine, 30 mg three times a day, a significant decrease in arterial blood pressure and systemic vascular resistance and a significant increase in the cardiac index, stroke volume index, and left ventricular stroke work index at rest were observed in response to a single oral dose of 30 mg nicardipine. Data at peak exercise were also obtained before and 2 hours after the oral administration of nicardipine. With this comparison there was a significant increase in cardiac index, stroke work index, and exercise duration. It is concluded that in this group of patients with severe chronic heart failure, nicardipine enhanced myocardial performance during rest and exercise and this enhancement is sustained after 9 days of oral therapy.

Diagnosis and treatment of streptococcal pharyngitis

Common signs and symptoms of streptococcal pharyngitis include sore throat, temperature greater than 100.4 degrees F (38 degrees C), tonsillar exudates, and cervical adenopathy. Cough, coryza, and diarrhea are more common with viral pharyngitis. Available diagnostic tests include throat culture and rapid antigen detection testing. Throat culture is considered the diagnostic standard, although the sensitivity and specificity of rapid antigen detection testing have improved significantly. The modified Centor score can be used to help physicians decide which patients need no testing, throat culture/rapid antigen detection testing, or empiric antibiotic therapy. Penicillin (10 days of oral therapy or one injection of intramuscular benzathine penicillin) is the treatment of choice because of cost, narrow spectrum of activity, and effectiveness. Amoxicillin is equally effective and more palatable. Erythromycin and first-generation cephalosporins are options in patients with penicillin allergy. Increased group A beta-hemolytic streptococcus (GABHS) treatment failure with penicillin has been reported. Although current guidelines recommend first-generation cephalosporins for persons with penicillin allergy, some advocate the use of cephalosporins in all nonallergic patients because of better GABHS eradication and effectiveness against chronic GABHS carriage. Chronic GABHS colonization is common despite appropriate use of antibiotic therapy. Chronic carriers are at low risk of transmitting disease or developing invasive GABHS infections, and there is generally no need to treat carriers. Whether tonsillectomy or adenoidectomy decreases the incidence of GABHS pharyngitis is poorly understood. At this time, the benefits are too small to outweigh the associated costs and surgical risks.

Staphylococcus aureus bacteremia in patients with acute leukemia

The natural history and outcome of Staphylococcus aureus bacteremia in patients with acute leukemia were studied over a 10 year period at the Baltimore Cancer Research Program. There were 370 patients at risk; 32 (9 percent) had 37 episodes. Granulocytopenia (less than 1,000/microliters) was present in 95 percent of the episodes. The sites of origin of bacteremia were identified in 32 episodes and were usually the skin and lower respiratory tract. Initially, broad-spectrum antimicrobials were used empirically in 30 episodes and specific antistaphylococcal therapy was used in the remaining seven episodes. The median duration of therapy was 14 days of intravenous therapy and seven days of oral therapy, a total of 21 days. There was improvement during therapy in 31 of the 37 episodes (83 percent) although, among the subgroup of six patients with shock, only one improved (p less than 0.001). There was no clinical or postmortem evidence of endocarditis in any patient. Since endocarditis complicating Staph. aureus bacteremia appears to be rare in patients with acute leukemia, a shorter course of therapy than that usually recommended for endocarditis may be justified.

Salicylate metabolism in twins. Evidence suggesting a genetic influence and induction of salicylurate formation.

To evaluate the contribution of genetic influences on the individual variation in plateau serum salicylate levels, salicylate metabolism was studied in seven pairs of identical and six pairs of fraternal twins.Under the conditions of this study, after a single i.v. dose (40 mg/kg) of sodium salicylate, the serum salicylate concentration versus time curve approximated a straight line on linear coordinates (appeared approximately zero order). The slopes of the decay curves ranged between 0.64 and 1.02. The intrapair variation for identical twin pairs was significantly less than for fraternal twin pairs (P = 0.044). Likewise pleateau serum salicylic acid concentrations (milligrams/deciliter) and total salicylic acid excretion rate after multiple doses demonstrated significantly less intrapair variation for identical twins than for fraternal twins (P = 0.043 and 0.006). Plateau salicylurate excretion (milligram/kilogram per hour) differences after multiple dosing had a P = 0.067. Michaelis-Menton constant for salicylurate formation and hours to 50% excretion after the i.v. dose were not different when comparing identical and nonidentical twins. Salicylurate formation rates were increased after 3 days of oral therapy, and this induction phenomenon may account for much of the apparent discrepancy between genetic influences on salicylurate formation rates observed after single and multiple dose salicylate administration. This study suggests that the plateau concentration of serum salicylate varies among individuals given the same weight-adjusted dose in part because of genetically determined variations in their metabolism of salicylate.

Bacteremia in Children: An Outpatient Clinical Review

In a 20-month period, 1,783 children seen in the pediatric outpatient department had blood cultures performed and 117 (6.5%) of these children had bacteremia. Two thirds of the isolates were Diplococcus pneumoniae and Hemophilus influenzae b. Ninety-three percent of children with H. influenzae b bacteremia and 20% of children with pneumococcal bacteremia had soft tissue involvement at the initial visit. Most children with positive blood cultures (102) were previously well and beyond the newborn period and many (46) had seemingly trivial illnesses initially: upper respiratory tract infection, fever of unknown origin, otitis media, and diarrhea. In the absence of soft tissue infection, the latter three diagnoses correlated best with bloodstream invasion. Nineteen children had persistent bacteremia and five developed soft tissue complications not noted initially. Two factors, age between 7 and 24 months and temperature between 39.4 and 40.6 C, showed increased specificity for bacteremia but were sensitive only for pneumococcal disease. A temperature larger than or equal to 40.5 C showed more specificity for bacteremia than lesser fevers. A white blood cell count greater than 20,000/cu mm was poorly sensitive, and pulmonary infiltrates were neither specific nor sensitive for positive blood cultures. Five bacteremic children had aseptic lymphocytosis in the cerebrospinal fluid. Two days of intravenous antibiotic therapy and eight days of oral therapy were adequate for pneumococcal bacteremia without soft tissue involvement. This therapy may not be without soft tissue involvement. This therapy may not be ideal, however, since other routes and duration of therapy were not evaluated.

DARK-ADAPTATION TESTING FOR DIAGNOSIS OF SUBCLINICAL VITAMIN-A DEFICIENCY AND EVALUATION OF THERAPY

Thirteen patients with chronic small-intestinal disease without overt evidence of nutritional deficit were found to have abnormal dark-adaptation tests. Ten patients were receiving 3500 to 10,000 units of vitamin A daily in oral multivitamin preparations. Dark adaptation did not change in five patients after a week of oral vitamin-A therapy (25,000 units per day). Normal dark adaptation was restored in two of four patients after a single dose of parenteral vitamin A (50,000 units) and in five of seven patients after 30 days of oral therapy (50,000 units per day). The high frequency of subclinical vitamin-A deficiency found in this group suggests that occult nutritional deficiency may be more prevalent in patients with intestinal disease than is commonly appreciated. Routine vitamin supplementation cannot be relied upon to prevent the functional deficit demonstrated in this study.