Changing patterns in academic allergy-immunology

In evaluation of the current Allergy-Immunology (AI) Program of the Department of Medicine at Northwestern University Medical School and in planning for the future, it appeared that our assessment of changes in the AI program since its inception might be of value to other AI academic programs. Further, we might receive suggestions from other academic AI programs, and we request such advice.

Allergen immunotherapy: a long-term perspective

Efficacy of standard IT to reduce medications and symptoms by at least 50% has been demonstrated multiple times. Reports of negative studies of IT deserve only evaluation of why the study design failed to demonstrate efficacy. Emphasis in the US and worldwide should be on education on the appropriate use of allergen IT, improvements in IT therapy, and preparation for the increased demand for allergists-immunologists as Fellowship training programs decline in numbers and individual training slots decrease.

Potential effect of the administration of substance P and allergen therapy on immunoglobulin E-mediated allergic reactions in human subjects

Previously we observed and reported that immunoglobulin E-mediated (IgE-mediated) allergy in rhesus monkeys was decreased by the administration of substance P (SP) and an allergen. We extended these studies to human subjects, giving SP and 1 allergen to subjects with reactivity to more than 1 allergen, using reactivity to a second allergen as a control. SP and an allergen were initially given by aerosol delivery but subsequently were given by injection. The administration of SP and 1 allergen by aerosol delivery or injection resulted in decreased IgE-mediated reactivity to the allergen administered and also to the control allergen. This result occurred in 7 of 8 human subjects. The 2 initial subjects receiving 8 SP and allergen injections had a sharp reduction in their symptoms of ragweed hay fever lasting for 3 years to date. No significant reactions to the injection of SP occurred. Further controlled human research is necessary on the administration of SP and allergen and the mechanisms of action. Unexpected and serendipitous results first observed in rhesus monkeys and reproduced in allergic human subjects provide a new and potential mechanism for control and perhaps obliteration of common IgE-mediated allergies and even more-serious allergic problems.

The decline and fall of Esperanto: lessons for standards committees

In 1887, Polish physician Ludovic Zamenhof introduced Esperanto, a simple, easy-to-learn planned language. His goal was to erase communication barriers between ethnic groups by providing them with a politically neutral, culturally free standard language. His ideas received both praise and condemnation from the leaders of his time. Interest in Esperanto peaked in the 1970s but has since faded somewhat. Despite the logical concept and intellectual appeal of a standard language, Esperanto has not evolved into a dominant worldwide language. Instead, English, with all its idiosyncrasies, is closest to an international lingua franca. Like Zamenhof, standards committees in medical informatics have recognized communication chaos and have tried to establish working models, with mixed results. In some cases, previously shunned proprietary systems have become the standard. A proposed standard, no matter how simple, logical, and well designed, may have difficulty displacing an imperfect but functional "real life" system.

Occlusion contributes to temporal processing differences between crossed and uncrossed stereopsis in random-dot displays

Stereoscopic depth discrimination was investigated in crossed and uncrossed directions using stimuli defined by binocular disparity differences embedded in dynamic random-dot stereograms. Across three experiments, fixation was directed to a point on the display screen (which placed crossed stimuli in front of and uncrossed stimuli behind, the background dots of the stereogram), to a point in front of the display screen (which placed both crossed and uncrossed stimuli in front of the background dots), and to a point behind the display screen (which placed both crossed and uncrossed stimuli behind the background dots). Results showed that depth discrimination was always good when the stimuli appeared in front of the background dots of the stereogram, whereas discrimination was always poor when the stimuli appeared behind the background dots. These results suggest that differences between crossed and uncrossed stereopsis as reported in past research arose, in part, from effects related to occlusion.

The role of the envelope in processing iterated rippled noise

Iterated rippled noise (IRN) is generated by a cascade of delay and add (the gain after the delay is 1.0) or delay and subtract (the gain is -1.0) operations. The delay and add/subtract operations impart a spectral ripple and a temporal regularity to the noise. The waveform fine structure is different in these two conditions, but the envelope can be extremely similar. Four experiments were used to determine conditions in which the processing of IRN stimuli might be mediated by the waveform fine structure or by the envelope. In experiments 1 and 3 listeners discriminated among three stimuli in a single-interval task: IRN stimuli generated with the delay and add operations (g = 1.0), IRN stimuli generated using the delay and subtract operations (g = -1.0), and a flat-spectrum noise stimulus. In experiment 2 the listeners were presented two IRN stimuli that differed in delay (4 vs 6 ms) and a flat-spectrum noise stimulus that was not an IRN stimulus. In experiments 1 and 2 both the envelope and waveform fine structure contained the spectral ripple and temporal regularity. In experiment 3 only the envelope had this spectral and temporal structure. In all experiments discrimination was determined as a function of high-pass filtering the stimuli, and listeners could discriminate between the two IRN stimuli up to frequency regions as high as 4000-6000 Hz. Listeners could discriminate the IRN stimuli from the flat-spectrum noise stimulus at even higher frequencies (as high as 8000 Hz), but these discriminations did not appear to depend on the pitch of the IRN stimuli. A control experiment (fourth experiment) suggests that IRN discriminations in high-frequency regions are probably not due entirely to low-frequency nonlinear distortion products. The results of the paper imply that pitch processing of IRN stimuli is based on the waveform fine structure.

Hypersensitivity pneumonitis due to humidifier disease: seek and ye shall find

STUDY OBJECTIVES

This study reports a classic case of hypersensitivity pneumonitis (HP) with classic histologic changes in lung tissue and the research used to identify the causative antigens.

DESIGN

A patient with clinical, radiographic, pulmonary function abnormalities and a lung biopsy consistent with HP had no identifiable antigen exposure.

SETTING

Evaluation of the patient's activities provided no suggestion of antigen exposure. Her home was evaluated. It was found that her humidifier ran continually without being cleaned but water was added periodically.

MEASUREMENTS

Serologic analysis demonstrated precipitating antibodies against her humidifier water and ten antigens in the hypersensitivity lung disease serologic panel.

CONCLUSION

Removal of the humidifier, cleaning of the house, and a course of prednisone resulted in the return of the patient to a normal state.

Cell-free hemoglobin preserves renal function during normothermic ischemia

INTRODUCTION

The purpose of this study is to determine whether an infusion of polymerized hemoglobin solution is capable of suppressing the tubular damage and loss of renal function normally seen during a clinically relevant period of warm ischemia.

METHODS

Male rats (350-450 g) were randomized to treatment with control (5% human serum albumin, HSA, n = 6) or test solution (9% polymerized hemoglobin, PHB, n = 6). Following a right nephrectomy, the left renal artery was perfused with 4 ml of HSA or PHB at 37 degreesC. The left renal artery was temporarily occluded for 50 min. At 72 h, creatinine (Cr), blood urea nitrogen (BUN), and percentage hemoglobin (Hb) were measured and the kidney was removed. Stained kidney sections were graded for ischemic injury (0-4, 0 = normal and 4 = necrosis of the proximal tubule). All results were expressed as means +/- SEM and statistical analysis was performed by t test.

RESULTS

Treatment with PHB resulted in lower Cr (1.2 +/- 0.23 mg/dl vs 3.26 +/- 0.60 mg/dl, P < 0.01) and BUN (60.5 +/- 12.7 mg/dl vs 151 +/- 20.2 mg/dl, P < 0.01) at 72 h compared to HSA controls. Total hemoglobin was not significantly different at 72 h. The weight of all treated kidneys increased; however, the increase was significantly less in the PHB-treated group (34 +/- 9.1% vs 70 +/- 7. 4%, P < 0.01). PHB-treated kidneys had less evidence of histologic damage compared to those in the HSA group (0.75 +/- 0.11 vs 2.50 +/- 0.64, P < 0.05).

CONCLUSIONS

During normothermic renal ischemia, renal artery infusion of PHB resulted in preservation of renal function and histologic architecture. PHB solutions may be useful in preserving organ function during prolonged periods of in vivo ischemia.

The cyclopean (stereoscopic) barber pole illusion

Across two experiments, this study found that the barber pole illusion (i.e. grating pattern appearing to move in the direction of the long axis of a rectangular aperture) is perceived with stereoscopic (cyclopean) motion. The grating and aperture comprising the barber pole display were created from binocular disparity differences embedded in a dynamic random-dot stereogram or from luminance differences. In Experiment 1, observers viewed a square-wave grating moving through a rectangular aperture of 2:1 or 4:1 aspect ratio and indicated whether the grating appeared to move in a direction perpendicular to its orientation or in the direction of the long axis of the aperture. For both stereoscopic and luminance stimuli equally, the grating appeared to move in the direction of the aperture (i.e. the barber pole illusion) more often with the larger aspect ratio than with the smaller aspect ratio. The condition for which a stereoscopic grating moved through a luminance rectangular aperture was also examined: the grating appeared to move in the direction of the aperture (inter-attribute barber pole illusion). In Experiment 2, observers viewed a square-wave grating moving through a rectangular aperture of 3:1 aspect ratio whose sides were indented in order to change the local direction of motion of the line terminators. For both stereoscopic and luminance stimuli, the grating appeared to move more frequently in a direction perpendicular to its orientation with the indented aperture (i.e. the illusion was diminished). Thus, local velocity signals from moving stereoscopic line terminators play a role in the production of the barber pole illusion similar to that of luminance motion signals. This suggests that the generation and propagation of motion signals at cyclopean levels of vision play a part in the representation of coherently-moving rigid surfaces.

Malignant cough equivalent asthma: definition and case reports

BACKGROUND

Cough equivalent asthma is a cause for chronic cough and usually responds to corticosteroid therapy. Oral corticosteroids are employed in a diagnostic-therapeutic trial and inhaled corticosteroids are employed in maintenance therapy. In certain cases the cough may be especially severe and require escalated doses of oral corticosteroids for initial control. This is labeled malignant cough equivalent asthma.

OBJECTIVE

To define malignant cough equivalent asthma, provide two case reports, and identify features that should alert physicians to consider the possibility of malignant cough equivalent asthma.

CASE REPORTS

We report two patients who presented complaining of chronic cough that was disruptive of sleep and normal activities, and in one patient prompted an emergency room visit and later hospitalization. The patients underwent evaluation with history, physical examination, and laboratory testing as indicated. Other causes for chronic cough were ruled out by appropriate testing, or were treated, and patients did not respond to usual corticosteroid treatment for cough equivalent asthma. These patients were considered to have a more severe form of cough equivalent asthma and did respond to treatment with higher doses of oral corticosteroids.

CONCLUSION

Malignant cough equivalent asthma is a cause of chronic cough that is disruptive to sleep or normal activities, may lead to emergency room visits or hospitalization, and requires escalated doses of oral corticosteroids for initial control.

A computerized reminder for prophylaxis of deep vein thrombosis in surgical patients

OBJECTIVE

To measure the effect of a computerized reminder system on the rate of deep vein thrombosis (DVT) prophylaxis in surgical patients.

DESIGN

A prospective trial to measure change in compliance compared to historic controls.

MEASUREMENTS

LDS Hospital surgeons developed local consensus as to which procedures should have DVT prophylaxis. The historic rate of prophylaxis for the procedures was measured through a database search of patient records. A computerized reminder system was then implemented which utilized an expert knowledge base and a time drive mechanism to flag surgical cases for DVT prophylaxis. For eligible patients, a DVT reminder appeared on the operating room schedule; surgical staff used this as a guide to apply prophylaxis. During the 3 month trial the rate of DVT prophylaxis was remeasured and compared to the pre-intervention rate.

RESULTS

The pre-intervention rate of DVT prophylaxis over a 3 month period was 85.2% (785 of 921 eligible cases). For the 3 months following the introduction of the computerized reminder, compliance with DVT prophylaxis increased to 99.3% (1084 of 1092 eligible cases). The difference between the historic controls and the study subjects was highly significant (p < 0.001).

CONCLUSION

A computerized reminder is an effective method of increasing the rate of DVT prophylaxis in surgical patients.

A case of idiopathic anaphylaxis associated with respiratory infections

BACKGROUND

Anaphylaxis is associated with IgE-mediated reactions to foods, drugs, and other allergens. Exercise-induced anaphylaxis and food plus exercise-induced anaphylaxis have been reported. Anaphylactoid reactions with no mechanisms determined have been described with radiographic contrast media. Idiopathic anaphylaxis by definition is anaphylaxis with no identifiable external allergen or stimulus. In our series of more than 350 patients with idiopathic anaphylaxis, extensive evaluation has failed to identify a cause for the anaphylaxis.

OBJECTIVE

To report a first case of idiopathic anaphylaxis associated with coryzal symptoms.

METHODS

A patient was evaluated for idiopathic anaphylaxis. Appropriate therapy was initiated.

RESULTS

The patient's anaphylactic episodes are related to the occurrence of coryzal symptoms but no clear IgE-mediated mechanism was identified.

CONCLUSION

This is the first reported association of anaphylaxis with an inciting factor of infection.

Ileal microvillar protein villin is tyrosine-phosphorylated and associates with PLC-gamma1. Role of cytoskeletal rearrangement in the carbachol-induced inhibition of ileal NaCl absorption

In ileal absorptive cells, carbachol inhibits NaCl absorption and its component brush border Na+/H+ exchanger, acting via basolateral membrane receptors. This carbachol effect involves (i) activation of brush border phosphatidylinositol 4,5-bisphosphate-specific phospholipase C (PLC) activity and brush border but not basolateral membrane translocation of PLC-gamma1 (Khurana, S., Kreydiyyeh, S., Aronzon, A., Hoogerwerf, W. A., Rhee, S. G., Donowitz, M., and Cohen, M. E. (1996) Biochem. J. 313, 509-518); and (ii) brush border tyrosine kinase(s) because mucosal but not serosal addition of the tyrosine kinase inhibitor genistein prevents the carbachol-induced inhibition of NaCl absorption and brush border Na+/H+ exchange. In the present work we identify a pool of villin (a brush border actin-binding protein) in the microvillus membrane fraction of rabbit ileum; this pool of villin is tyrosine-phosphorylated and associates with brush border membrane PLC-gamma1. Villin is present both in the Triton X-100-soluble and -insoluble fractions of the brush border. The Triton X-100-soluble pool is approximately 4-fold smaller than the brush border pool of villin that is present in the Triton X-100-insoluble fraction. Only the villin present in the Triton X-100-soluble fraction of ileal villus brush border associates with PLC-gamma1 and is tyrosine-phosphorylated. Carbachol increases the tyrosine phosphorylation of villin rapidly (as early as 30 s) and transiently. Carbachol also increases the amount of tyrosine-phosphorylated villin that associates with PLC-gamma1. These studies demonstrate that carbachol effects on NaCl absorption are accompanied by an increase in brush border PLC-gamma1 association with villin and an increase in tyrosine phosphorylation of villin. To study the role of cytoskeletal rearrangement in carbachol-induced inhibition of NaCl absorption, we used the F-actin stabilizing drug jasplakinolide. Jasplakinolide prevents the carbachol inhibition of ileal NaCl absorption. This suggests that F-actin severing is necessary for carbachol to inhibit ileal villus NaCl absorption. Since villin is known to sever actin, these studies suggest a role for villin in the signaling cascade that begins at the basolateral membrane with carbachol binding to its receptor and ends at the apical membrane in inhibition of NaCl absorption.

Airways obstruction in patients with long-term asthma consistent with 'irreversible asthma'

OBJECTIVE

To describe a series of eight patients with long-term asthma and pulmonary function consistent with "end-stage," irreversible obstruction.

DESIGN

Retrospective descriptive analysis of patients with severe asthma.

SETTING

A university-based allergy-immunology service with a large population of corticosteroid-dependent patients with asthma.

PATIENTS

Eight patients with long-standing asthma and apparently irreversible airways obstruction despite long-term oral and inhaled corticosteroid therapy.

MEASUREMENTS

Pulmonary function data, radiographic studies including chest radiograph and high-resolution CT of the chest, and serologic analysis to rule out allergic bronchopulmonary aspergillosis and alpha1-antitrypsin deficiency had been performed as indicated, and these results were obtained through chart review.

RESULTS

The age of the patients ranged from 41 to 58 years, with a mean duration of asthma of 39 years (SD = 12.4 years). No patient had evidence of any other pulmonary disease process. The mean duration of daily or alternate-day oral corticosteroid treatment was 15.8 years (SD=11.8 years). Despite intensive pharmacotherapy, all patients had an FEV1 57% (42+/-12%) with marked small airways disease as reflected in the forced expiratory flow between 25% and 75% of the FVC. Three of the eight patients demonstrated an accelerated decline in FEV1 despite continuous systemic corticosteroids.

CONCLUSIONS

We have described a series of eight patients with long-standing asthma who demonstrate irreversible airways obstruction despite long-term systemic and inhaled corticosteroids. The term "end-stage asthma" or irreversible asthma might be applied to these patients in whom fixed obstruction has occurred in the absence of other pulmonary diseases.

Pediatric idiopathic anaphylaxis: experience with 22 patients

Idiopathic anaphylaxis in the pediatric population is being increasingly recognized, with symptoms (and therefore classifications) the same as those described in adults. We present a series of 22 patients with special attention to considerations relatively unique to the pediatric population. Prednisone, hydroxyzine, and albuterol were used to control symptoms and induce remission. No deaths occurred during treatment. One adolescent who presented with corticosteroid-dependent idiopathic anaphylaxis was diagnosed with undifferentiated somatoform-idiopathic anaphylaxis. Local physician reluctance to participate in management complicated care for some patients.

Direction discrimination of cyclopean (stereoscopic) and luminance motion

This study compared direction discrimination of cyclopean (stereoscopic) and luminance motion involving stimuli equated for effective strength. The stimuli were random-walk cinematogram (RWC) displays whose signal and noise discs were created from binocular disparity differences embedded in a dynamic random-dot stereogram or from luminance differences. Experiment 1 measured global motion detection thresholds for cyclopean and luminance stimuli by manipulating the proportion of signal to noise discs. Detection thresholds for cyclopean motion were about 25% whereas detection thresholds for luminance motion were 5%, thus five times more cyclopean motion events than luminance events were necessary to elicit threshold responding. Experiment 2 measured thresholds for discriminating the direction of cyclopean and luminance motion under conditions of equal stimulus strength by presenting the motion displays at equal multiples of detection threshold. Direction discrimination thresholds (ranging from about 5-30 deg, depending upon conditions) were similar for cyclopean and luminance motion, thus the precision with which the pooling of local motion events in one direction can be discriminated from the pooling of events in a slightly different direction is the same for cyclopean and luminance stimuli. The finding that cyclopean motion information is pooled is consistent with the idea that the direction of cyclopean motion is coded in the responses of a population of directionally selective mechanisms.

Malignant and corticosteroid-dependent idiopathic anaphylaxis: successful responses to ketotifen

BACKGROUND

Malignant idiopathic anaphylaxis refers to the most severe form of idiopathic anaphylaxis where defined episodes of idiopathic anaphylaxis are not controlled when the prednisone is reduced below at least 60 mg every other day or 20 mg daily. Corticosteroid-dependent idiopathic anaphylaxis refers to patients with idiopathic anaphylaxis who require continuous daily or alternate day prednisone at threshold doses for control of idiopathic anaphylaxis. Ketotifen has been reported to help induce remission in some patients with idiopathic anaphylaxis and has steroid sparing effects in other patients with idiopathic anaphylaxis.

METHODS

We present five patients, two with malignant idiopathic anaphylaxis and three with corticosteroid-dependent idiopathic anaphylaxis, who responded to the administration of ketotifen.

RESULTS

All five patients, while receiving ketotifen, had a reduction or resolution of their episodes of idiopathic anaphylaxis and prednisone was tapered and discontinued.

CONCLUSION

Ketotifen is shown to be successful in inducing remission in two patients with malignant idiopathic anaphylaxis and in three additional patients with corticosteroid-dependent idiopathic anaphylaxis. An additional patient with malignant idiopathic anaphylaxis had prednisone stopped after elective hip surgery.