PubMed Health⌕ Search

Biomedical subjects

R Patterson

Publications and source records attributed to R Patterson.

At least 91 records · Page 5Linked to original sources
PubMed1996

Basement shower hypersensitivity pneumonitis secondary to Epicoccum nigrum.

Two children developed hypersensitivity pneumonitis after extensive exposure to an unventilated basement shower. Commercial precipitin panels were negative. After home inspection, individual mold species were isolated from the household and extracted. Precipitating antibodies to Epicoccum nigrum were found in both children. Resolution of the hypersensitivity pneumonitis occurred with avoidance and glucocorticosteroid therapy. E nigrum is a newly identified etiologic agent for hypersensitivity pneumonitis found in a mold-contaminated home.

Allergens↗
PubMed1996

Idiopathic anaphylaxis: long-term follow-up, cost, and outlook.

To determine the efficacy of oral corticosteroids, antihistamines, and sympathomimetics in treating patients with idiopathic anaphylaxis, the charts of 225 patients diagnosed with idiopathic anaphylaxis from 1971 to 1990 treated at a single center were reviewed. Sixty-one patients (34 females and 27 males) were available for long-term follow-up. Ages ranged from 10 to 68 years with an average of 39 years. Patients with frequent episodes were treated with a protocol of oral corticosteroids, antihistamines, and sympathomimetics. Patients with infrequent episodes were treated for acute episodes only. The number of emergency room visits, hospitalizations, intensive care unit admissions, and length of time in remission were recorded. Sixty-five percent of patients with infrequent episodes and 91% of patients with frequent episodes of idiopathic anaphylaxis went into remission. Significant decreases in emergency room visits occurred for the idiopathic anaphylaxis-generalized-frequent group (P < 0.016), the idiopathic-anaphylaxis-generalized-infrequent group (P < 0.0001), and the idiopathic anaphylaxis-angioedema-infrequent group (P < 0.039). Significant decreases in the number of hospitalizations (P < 0.022) and intensive care unit admissions (P < 0.009) occurred for the idiopathic anaphylaxis-generalized-infrequent and frequent groups, respectively. Overall, an estimated $184 740 was saved with the treatment program, for 546 patient-years. Idiopathic anaphylaxis can be controlled and remission induced in most patients. An estimated $11 million per year can be saved for patients in the USA on the basis of the estimated prevalence in this country.

Adolescent↗
PubMed1995

Idiopathic anaphylaxis. An attempt to estimate the incidence in the United States.

BACKGROUND: Idiopathic anaphylaxis has been described and classified, and increasing numbers of cases are being seen in the United States and abroad. Treatment regimens have been shown to be effective in prophylactic management. There is no available information about the number of cases in the United States. METHODS: We attempted to determine the number of cases of idiopathic anaphylaxis in the United States by mailing a questionnaire to all graduates (for the last 31 years) of the Northwestern University Allergy-Immunology Fellowship training program. RESULTS: Response to the questionnaire was 100%, and 633 cases were reported by this survey of 75 allergists. The current total number of identified cases of idiopathic anaphylaxis from all reports of cases in the United States is 1020. CONCLUSIONS: By extrapolation of the cases of idiopathic anaphylaxis reported by the allergists surveyed to the approximately 4000 allergists in the United States, the estimated number of cases in the United States is between 20,592 and 47,024. Idiopathic anaphylaxis is potentially fatal, represents a source of major medical health care costs, causes anxiety to patients and families, occurs in pediatric and adult populations, and is controlled by appropriate regimens. The estimated number of cases emphasizes the need for careful attention to idiopathic anaphylaxis by physicians.

Anaphylaxis↗
PubMed1995

Undifferentiated somatoform idiopathic anaphylaxis: nonorganic symptoms mimicking idiopathic anaphylaxis.

BACKGROUND: Northwestern University's Division of Allergy and Immunology has had experience with the diagnosis and treatment of more than 350 patients with idiopathic anaphylaxis (IA). In 1992 we reported a group of patients with IA whose presentations mimicked IA, but IA and other organic causes were later excluded. Psychologic factors were suspected as the underlying problem. These patients were classified as IA-variant. Management of these cases was extremely difficult. There was significant morbidity and high and unnecessary costs. OBJECTIVE: We aim to distinguish the nature of this disease and to highlight the evaluation and treatment of this group of patients. METHODS: Their cases are reviewed and reported. RESULTS: Common features included (1) presenting symptoms mimicking IA, (2) no objective findings that correlated with 1, (3) no response to the therapeutic regimen for IA, (4) meeting the Diagnostic and Statistical Manual of Mental Disorders criteria for undifferentiated somatoform disorder, and (5) significant wasted health care expenditure. CONCLUSIONS: This group of patients were better defined as having undifferentiated somatoform-IA. An algorithm was proposed to expedite the diagnosis of the disease so that with early recognition of the disease, unwarranted repetitive consultations, tests, and inappropriate therapy can be avoided.

Adult↗
PubMed1995

Multiple sources of the impedance cardiogram based on 3-D finite difference human thorax models.

Two 3-D electrical models of the human thorax, each consisting of 216,000 control volumes, were constructed based upon MR images taken at end diastole and end systole. Using the finite difference method, the contributions of various sources to the impedance cardiogram were studied for the traditional band electrode configuration. The contributions were categorized into three areas: 1) the structural changes between end diastole and end systole, 2) the flow-induced blood resistivity changes in major arteries and veins, and 3) the lung resistivity variation due to the lung blood volume change. Based on the models, Zo and delta Z between end diastole and end systole were 24.4 omega and -0.132 omega, as compared with the measurements of 21.8 omega and -0.123 omega made on the same subject from whom the images were taken. Arterial and venous blood resistivity changes caused approximately 57% of the total impedance change. The lung resistivity change and the structural changes contributed 39% and 4%, respectively. The structural changes inside the thorax included the dimensional changes of blood vessels, the blood volume changes of the heart chambers, and heart movement. Although the net impedance change due to the structural changes was relatively small, the individual variation of various factors was large, with significant cancellation occurring. The results suggest that the thoracic impedance cardiographic signal is a mixed representation of many inseparable factors and may not be reliable for the stroke volume calculation. Also, the O-wave, which is clinically observed in various cardiac conditions, may be linked to the diastolic blood flow in the central veins.

Adult↗
PubMed1995

Allergic bronchopulmonary mycosis caused by Fusarium vasinfectum.

We present a case of allergic bronchopulmonary fusariosis (ABPF). This is the first case of allergic bronchopulmonary mycosis (ABPM) caused by Fusarium vasinfectum reported in the medical literature. The patient presented with a history and radiographic picture highly suggestive of allergic bronchopulmonary aspergillosis (ABPA), yet with negative ABPA serology results. The demonstration of a positive skin test and precipitins against F. vasinfectum, elevated serum IgG and IgE antibodies against F. vasinfectum, and a decline in total serum IgE with treatment clearly establish the diagnosis of ABPF. The diagnosis of ABPM caused by organisms other than Aspergillus represents an important consideration in patients who appear clinically to have ABPA but whose serology results do not confirm this diagnosis. As in ABPA, early diagnosis and appropriate therapy may be necessary in order to prevent progressive lung disease.

Aspergillosis, Allergic Bronchopulmonary↗
PubMed1995

Temporal integration differences between crossed and uncrossed stereoscopic mechanisms.

In this study, we investigated temporal integration of disparity information for crossed and uncrossed stereopsis. Across three experiments, exposure duration thresholds were measured for stereoscopic stimuli created from dynamic random-dot stereograms. In Experiment 1, an investigation of disparity detection showed that detection thresholds were equal for the crossed and uncrossed directions. In Experiment 2, an examination of duration limits for depth perception showed that critical durations were lower, and depth more veridical, for crossed depth than for uncrossed depth. In Experiment 3, an investigation of depth discrimination revealed that discrimination thresholds were lower for crossed depth than for uncrossed depth. These results suggest that crossed and uncrossed mechanisms differ in terms of their temporal integration properties at processing levels involving the computation and discrimination of depth.

Depth Perception↗
PubMed1995

Influence of flicker on perceived size and depth.

Previous research (e.g., Wong & Weisstein, 1984a, 1985) has shown that flickering stimuli appear to be more distant than nonflickering stimuli at the same physical distance. Given this relation between flicker and perceived depth, inappropriate constancy scaling theories predict that flickering stimuli should be perceived as larger than nonflickering ones. In contrast, links between flicker and motion perception suggest that flickering stimuli should be perceived as smaller than nonflickering ones. Two experiments tested these contrasting predictions. In Experiment 1, 22 subjects compared flickering and nonflickering vertical lines and reported that the flickering stimulus appeared significantly smaller than the nonflickering one. In Experiment 2, 21 subjects reported that the stimuli used in Experiment 1 produced depth effects similar to those reported in previous experiments: flickering stimuli were perceived as more distant than nonflickering ones. The observed effect of flicker on perceived size was contrary to predictions from inappropriate constancy scaling theory, but consistent with views that motion and flicker are processed by the same pathway.

Adolescent↗
PubMed1995

Multifactorial immunologic lung disease: a case report.

BACKGROUND: Allergic asthma, allergic bronchopulmonary aspergillosis, and hypersensitivity pneumonitis are all forms of immunologically mediated lung disease. Recognition that more than one of these diseases may co-exist is necessary for proper patient management. OBJECTIVE: To report a case of extrinsic (cat) asthma, allergic bronchopulmonary aspergillosis, hypersensitivity pneumonitis, and potentially fatal asthma. Immunologic mechanisms and treatment of these diseases are discussed. METHODS: The study is a case report from a university hospital setting. Serum precipitating antibodies against avian antigens were measured using gel-diffusion technique. Serum IgE levels were measured and skin testing was performed to selected antigens. RESULTS: The patient had positive cutaneous reactivity to cat antigen and Aspergillus. Serology for allergic bronchopulmonary aspergillosis and serum precipitating antibodies to finch extract were positive. Symptoms improved and prednisone requirements decreased after removal of finches. CONCLUSION: A case of cat asthma, potentially fatal asthma, allergic bronchopulmonary aspergillosis, and hypersensitivity pneumonitis is presented. Early recognition and treatment of multifactorial immunologic lung disease with avoidance measures and use of corticosteroids can prevent progressive respiratory damage.

Adult↗
PubMed1995

Allergic bronchopulmonary aspergillosis presenting with cough variant asthma and identifiable source of Aspergillus fumigatus.

BACKGROUND: A 76-year-old man developed allergic bronchopulmonary aspergillosis initially presenting with cough variant asthma. Symptoms worsened after exposure to ground mulch which was an identifiable source of Aspergillus fumigatus. Symptoms improved after corticosteroids and avoidance measures were instituted. OBJECTIVE: To report a case of allergic bronchopulmonary aspergillosis presenting as cough variant asthma with identifiable source of Aspergillus fumigatus. METHODS: Single case report. Serum precipitating antibodies against Aspergillus fumigatus were tested using gel diffusion techniques. Total IgE, specific IgE, and IgG indices were measured by ELISA. Cutaneous reactivity to Aspergillus fumigatus was also tested. RESULTS: Skin test and serum precipitating antibodies to Aspergillus fumigatus were positive. Precipitins were also detected between Aspergillus fumigatus and the mulch. Total serum IgE was 538 IU/mL (1290 ng/mL) which declined to 228 IU/mL (544 ng/mL) after corticosteroid therapy. IgE index = 1.10 and IgG index = 2.86. CONCLUSION: Allergic bronchopulmonary aspergillosis can present as cough variant asthma. Identification of exacerbating factors such as sources of Aspergillus fumigatus are important in management.

Aged↗
PubMed1995

Hypersensitivity pneumonitis from residential composting: residential composter's lung.

Hypersensitivity pneumonitis results when a susceptible individual is exposed to sufficient airborne material capable of inducing a systemic and pulmonary immune response. We describe a man who had all the classic manifestations of hypersensitivity pneumonitis but in whom the circumstances of sensitization, residential yard work with composted yard clippings, has not previously been reported. We call this new entity residential composter's lung.

Adult↗
PubMed1995

Recurrent anaphylaxis due to unrecognized latex hypersensitivity in two healthcare professionals.

BACKGROUND: Anaphylaxis is a potentially fatal immediate-type reaction and intense effort may be required to identify the allergen responsible. In some cases, a "hidden" allergen may be responsible that is not apparent in spite of careful clinical assessment. OBJECTIVES: This report describes the assessment of two cases of anaphylaxis in which a search for an allergen was initially not conclusive and the diagnosis of idiopathic anaphylaxis was considered. METHODS: Two patients were evaluated by various physicians for anaphylaxis with no clear indication of a responsible allergen. Persistence in evaluation led to the identification of the allergen responsible. RESULTS: In two health care workers latex was identified as the "hidden" cause of anaphylaxis. This allergen had not been considered in either case in initial evaluations. Neither patient has had a recurrence of anaphylaxis since latex was identified as the cause of anaphylaxis. CONCLUSIONS: Although latex is widely recognized as a cause of anaphylaxis, it can still be unrecognized in some cases of recurrent anaphylaxis. Latex must be considered as a "hidden" cause of anaphylaxis, particularly in health care workers.

Adult↗
PubMed1995

Hypersensitivity pneumonitis in a raptor handler and a wild bird fancier.

BACKGROUND: Hypersensitivity pneumonitis has been associated with a variety of antigens in various settings. We have recently encountered one case of hypersensitivity pneumonitis from owl droppings and another case from a wild Moluccan cockatoo. OBJECTIVE: It is important to alert physicians to the possibility of hypersensitivity pneumonitis when dealing with wildlife workers and wild bird fanciers. METHOD: A report of two cases with progress and response to therapy. RESULTS: Clinical and serologic information are of value in the diagnosis of hypersensitivity pneumonitis due to birds and avoidance is the optimal approach. CONCLUSION: There are many raptor handlers and wild bird fanciers across the United States and the world. Given the incidence of hypersensitivity pneumonitis in pigeon breeders, this may herald a new variant of allergic disease among wildlife workers and wild bird fanciers.

Adult↗