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Biomedical subjects

R M Katz

Publications and source records attributed to R M Katz.

At least 19 recordsLinked to original sources

Pediatric airway manifestations of gastroesophageal reflux.

Gastroesophageal reflux (GER) in children may be classified as physiologic or pathologic, depending on its degree and consequences. There are many head and neck complications of GER in pediatric patients, but most numerous are the airway manifestations, including stridor, recurrent croup, exacerbation of subglottic stenosis, laryngeal irritation with or without laryngospasm, chronic cough, and obstructive apnea. Diagnosis may be difficult unless there is a high index of suspicion for GER and awareness of the concept of "silent" GER. We present the common pediatric airway manifestations of GER, illustrated by case reports, and provide a paradigm to assist in the diagnosis and management of children with airway compromise associated with GER.

Airway Obstruction

Effect of terfenadine in asthmatic patients.

The bronchodilator effect of terfenadine, 60-mg or 120-mg single dose, and 1 week twice daily dosing, was evaluated in 12 allergic asthmatic patients. When compared with baseline, FEV1 rose significantly for single dose 120 mg terfenadine at one, one and one-half, three, five and one-half, and six hours and for 60 mg terfenadine at three, five and one-half, six, and eight hours postdose. Variations in patient response were observed. At steady state, 120 mg terfenadine b.i.d. showed consistent improvement over placebo from three to 12 hours postdosing but no improvement in FEV1 was noted for terfenadine, 60 mg b.i.d. There no longer was a statistically significant difference in mean FEV1 or percent change from baseline. Thus, terfenadine proved to be a safe and a mild bronchodilator; however, tachyphylaxis might develop to the bronchodilator effect after 1 week of continuous b.i.d. dosing.

Asthma

Compliance in clinical trials of two nonbronchodilator, antiasthma medications.

An electronic monitoring device was used to assess patient compliance during clinical trials of two new aerosolized nonbronchodilator, antiasthma drugs. Compliance was poor, but similar, in both trials. Patients took the study drug as instructed on a mean of 37.3% days (range 10% to 77%) in one trial and 37.4% days (range 0% to 63%) in the other. Both underuse and overuse were observed. Underuse was seen on a mean of 38.9% days (range 9% to 81%) and 46.0% (range 15% to 80%) respectively; overuse on a mean of 23.5% days (range 6% to 54%) and 16.6% days (range 0% to 41%). In some patients ten or more activations of the device were recorded at the same time. In six patients such multiple simultaneous activations were recorded on two or more separate days. These patients were among the most noncompliant in the study. Multiple simultaneous activations frequently followed underuse days or preceded followup visits, suggesting the possibility of duplicity. Overall compliance was such that valid conclusions about efficacy of the drugs could only have been drawn in six of 34 patients.

Administration, Inhalation

The microbiology of chronic sinus disease in children with respiratory allergy.

Chronic maxillary sinusitis is common in children with respiratory allergy and is associated with increased morbidity. The bacteriology of chronic sinus disease in these children has not been adequately evaluated. Between May 1987 and January 1988, 12 children (aged 3 to 9 years), all with documented respiratory allergy and chronic respiratory symptoms consistent with chronic sinusitis (greater than 30 days), were fully evaluated. History, physical examination, complete blood count, nasal smear, and Waters x-ray were done. All patients had opacification of one or both maxillary sinuses, failed to respond to multiple courses of antibiotics, and subsequently underwent maxillary sinus aspiration and irrigation. Specimens were cultured for aerobic and anaerobic organisms with standard technique, and sensitivities were obtained. Culture results revealed a single organism (Moraxella [Branhamella] catarrhalis) in five patients, one patient yielded M. catarrhalis plus Streptococcus species, three were negative, and three patients grew multiple organisms (two with multiple aerobic streptococcal species and one patient with aerobic streptococci and Peptostreptococcus). All children received appropriate culture-directed antimicrobial therapy. Sequential biweekly follow-up revealed progressive radiographic clearing and significant symptomatic improvement. M. catarrhalis is a common pathogen, whereas anaerobic organisms are unusual as a cause of chronic maxillary sinusitis in allergic children. Some children, despite negative cultures, may benefit from maxillary sinus irrigation.

Child

The natural history and response to therapy of chronic urticaria and angioedema.

Previous reports have suggested that the etiology of chronic urticaria/angioedema (greater than 6 weeks) can be identified 10% to 30% of the time while few reports have addressed the natural history of chronic urticaria/angioedema. An analysis of all patients referred to the authors' practice between 1983-1985 with a diagnosis of urticaria/angioedema was performed. Patients with hereditary angioedema were excluded. Eighty-six of the 214 patients had chronic urticaria/angioedema. In the remaining 128 cases of acute urticaria there were four exercise induced, nine contact, six cold induced, six drug induced, 11 food induced, one viral hepatitis associated, 29 with dermographism, and 62 undetermined. An etiology could not be determined in any of the patients with chronic urticaria/angioedema. Laboratory tests, including CBC, chemistry panel, urinalysis, ANA, rheumatoid factor, complement studies, sedimentation rate, and skin tests were all noninformative. Chronic angioedema without urticaria occurred in only nine cases, 31 cases had chronic urticaria alone, and 46 cases had both chronic urticaria and angioedema. Of the patients followed over the 3-year period, 27 resolved while 48 continued to have urticaria/angioedema. Response to medications was variable and will be discussed. Our study suggests that an etiology is determined in much less than 10% of patients with chronic urticaria; fortunately, 32% of our cases resolved over a 3-year period.

Adrenal Cortex Hormones

Chronic sinusitis in the allergic child.

Chronic inflammation of the paranasal sinuses, especially the maxillary sinuses, is common in children with respiratory allergy. The presence of sinusitis should be suspected in such children when they have chronic night and early morning cough or poorly controlled asthma. Treatment should be aggressive because morbidity can be high.

Adolescent

Pharmacodynamic evaluation of azelastine in subjects with asthma.

A broad antiallergic compound called azelastine was studied pharmacodynamically in 34 subjects to correlate bronchodilator effect with blood levels of azelastine and desmethyl azelastine, its major metabolic product in man. Despite azelastine and desmethyl azelastine blood levels that were proportionate to the dosage range, the bronchodilator effect as measured by FEV1 and forced expiratory flow rate between 25% and 75% of FVC was proportionately greater with 4 mg of azelastine during the 8-hour study period than the anticipated bronchodilator response with the 8 and 16 mg doses. Azelastine, already proven effective in allergic rhinitis, has a bronchodilator effect at doses that do not produce intolerable side effects.

Adolescent

A comparison of inhaled albuterol and cromolyn in the prophylaxis of exercise-induced bronchospasm.

Inhaled albuterol and cromolyn by spinhaler have both been shown to be effective in the treatment of exercise-induced bronchospasm. Eighty subjects with exercise-induced bronchospasm participated in a randomized parallel group study comparing albuterol (180 microgram) and cromolyn (20 mg) administered 15 minutes prior to a standardized treadmill challenge. The cromolyn group was restudied after 2 and 4 weeks of 4 times/day cromolyn therapy. The albuterol group was also studied at 2 and 4 weeks, but they only used their inhaler as needed between study visits. The mean maximum FEV1 drop post-exercise in the albuterol group improved from 33% (screening visit) to 6% (treatment day 1). The cromolyn group showed significantly less (P less than .01) improvement than the albuterol group (31% drop at the screening visit to 14% drop at treatment day 1). When 2 or 4 weeks of continuous cromolyn therapy was given in addition to a dosage 15 minutes prior to exercise, there was no significant difference compared with acute cromolyn administration alone. In summary, acute administration of albuterol was better prophylaxis for exercise-induced bronchospasm than acute or chronic cromolyn treatment.

Administration, Inhalation

Use of a tube spacer to improve the efficacy of a metered-dose inhaler in asthmatic children.

Many children with asthma do not use the standard metered-dose inhaler (MDI) skillfully. To improve drug delivery, correct problems of hand-lung incoordination, and reduce local side effects, a number of spacer devices have been developed. We evaluated one such device, a tube spacer (Aerochamber), in 16 asthmatic children (5 to 12 years). On four separate days and in a randomized, double-blind, placebo-controlled manner, they received either metaproterenol sulfate by MDI aerosol (130 micrograms) or placebo with and without the tube spacer. To maximize techniques, at each visit the children had proper instructions, including viewing a videotape. Spirometry was performed at baseline and 5, 15, and 30 minutes, and hourly for six hours, and the patient was monitored. Analysis of the entire group (forced expiratory volume at 1 s and midmaximal expiratory volume) revealed no difference between metaproterenol administered with or without the tube spacer, and both were significantly different than placebo through two hours. Six children had longer and three had better bronchodilatation with the MDI plus tube spacer than with the MDI alone. Side effects and vital signs did not differ between treatments. Under the circumstances of our study, the tube spacer device might enhance the use of the MDI in children who are not properly taught and/or who forget or cannot perform proper technique.

Asthma

Correlation between A-mode ultrasound and radiography in the diagnosis of maxillary sinusitis.

A-mode ultrasound examination of the maxillary sinuses with the Echosine and Sinusvu 2500 units was compared with roentgenographic examination in the diagnosis of maxillary and frontal sinusitis. A-mode ultrasound was primarily useful in the detection of secretions within the sinus and not mucosal thickening. Both ultrasound devices had high specificities (92% for Echosine and 94% for Sinusvu 2500) in the diagnosis of maxillary sinusitis, but the Echosine had a greater overall sensitivity (61%) than the Sinusvu 2500 (29%). More significantly, as the opacification of the roentgenogram increased (a higher probability of secretion), the Echosine demonstrated better agreement with the x-ray film. Ultrasound appeared to be less helpful in diagnosing frontal sinusitis, but there were too few cases of frontal sinusitis for statistical analysis. The Echosine is a useful screening device because of the high specificity of a positive result. Although A-mode ultrasound provides limited value in diagnosing mucosal thickening, it is particularly useful in following the course of therapy once a positive diagnosis of sinusitis has been established without subjecting the patient to additional x-ray exposure.

Adolescent

Efficacy of doxepin in the treatment of chronic idiopathic urticaria.

Doxepin hydrochloride, a tricyclic antidepressant, was evaluated in a double-blind, placebo-controlled crossover trial for the treatment of chronic idiopathic urticaria in 16 adults. Efficacy was evaluated by symptom scores, concomitant antihistamine use, and suppression of histamine- and codeine-induced wheal response. Doxepin-treated subjects experienced fewer lesions (p less than 0.001), less waking hours with lesions (p less than 0.01), lesser degree of itch and/or discomfort (p less than 0.001), and less swelling or angioedema (p less than 0.001) as compared to placebo-treated subjects. Doxepin-treated subjects required less daily concomitant antihistamine use (mean 0.13 tablets versus 1.48 tablets, p less than 0.05). Doxepin also significantly suppressed histamine- and codeine-induced cutaneous wheal response as compared to placebo. Lethargy was commonly observed but diminished with continued use. Dry mouth and constipation were also commonly observed. We conclude that doxepin is an effective agent for the treatment of chronic idiopathic urticaria.

Chlorpheniramine

Compliance of patients with asthma with an experimental aerosolized medication: implications for controlled clinical trials.

A Nebulizer Chronolog, a portable device that houses a standard nebulizer canister, was used in a unique method to measure compliance with aerosolized medication. Each actuation is tabulated to within 4 minutes of the actual time of usage and can subsequently be displayed in a day-hour-minute format. Of the 19 patients studied for 12 weeks with a cromolyn-like agent, appropriate usage four times a day ranged from 4.3% to 94.8%. Underusage exceeded overusage and ranged from 5.2% to 95% of the study days. Younger subjects and male subjects were less likely to use the aerosol appropriately. Patients failed to write the truth in their diaries with overreporting of appropriate usage more than 50% of the times. Lack of compliance with aerosolized medication represents an important medical issue for the physicians caring for patients with asthma. The Nebulizer Chronolog elicits new insight into the disparity between reported and observed compliance.

Adolescent

Prevention with and without the use of medications for exercise-induced asthma.

Exercise-induced asthma or bronchospasm occurs in approximately 12% of the population. It can be prevented with proper techniques of exercise and environmental exposures and with medication. Exercise techniques include timing of exercise to less than 5-min interludes and continued repeat exercise every hour. Exercising to less than full tolerance may avoid the onset of exercise-induced asthma. In some individuals exercise in warm, humidified air is less asthmogenic than in dry, cold air. Medications that are effective and safe include bronchodilators such as theophylline and beta-agonists and prevention with cromolyn sodium in the atopic or sulfite exposed individual.

Asthma