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- Animals -
4/14/05 re: Immunotherapy with cattle and goat extracts I have a vetinarian who has classic symptoms of allergic rhinitis and symptoms of bronchospasm when exposed to farm animal barns. Skin tests to a variety of common aeroallergens were positive. We special ordered goat and cattle epithelia and were found to be very positive. Horse was negative. I would like to offer immunotherapy, but would like to know if there is any information regarding immunotherapy with goat and cattle extratcts. Specifically, doses (Where to start and maintenance doses). Any help is appreciated.
To my knowledge there are no commercial standardized cattle and goat extracts for allergy immunotherapy. Considering the relatively low demand for such extracts and the costs involved in getting FDA approval, I suspect that there will not be such standardized extracts on the near horizon.
That does not mean that someone is not making/using some crude, non-standardized cattle or goat epithelial extracts. However, one would have to be very cautious about administering such extracts to make sure no adverse effects and obtaining some evidence of efficacy. Of course, one should approach the allergies to aeroallergens such as those in hay (generally timothy and maybe alfalfa) with immunotherapy if advisable.
You have likely already advised your patient about avoidance measures. There are some fairly effective particle filter masks that are not uncomfortable to wear. The patient should be also advised to change all clothing when entering and leaving the barn so that the clothing exposed to the animal allergens never leave the barn (except for periodic high temperature water washing by themselves). A recent study show that such clothing changes on entering school by children who came from cat-owning homes significantly reduced the amount of cat allergen passaged among classmates in that school.
2/4/05 re: Rodent allergens for skin testing Is there a commercial source for mouse/rodent antigen for clinical testing?
As you may know, much of the recent investigation into allergy to rodent allergens in the USA has been carried out by Dr. Peyton Eggleston and his colleagues in Johns Hopkins Medical Center. I have enclosed below abstracts of some of their recent reports in this area of study. I then obtained input from Dr. Eggleston after some delay because he was out of town. His comments are enclosed below. As you can see, he feels that there is not significant difference in the quality of rodent skin test extracts from different commercial extract suppliers, allowing that there may be considerable difference in the potency of different lots even from the same supplier. If you are not familiar with such suppliers, some of the larger companies are Alk-Abello, Hollister-Stier, and Greer.
Dr. Eggleston's comments:
Mouse and rat allergen extracts have been available for years through all allergen extract manufacturers. Most manufacturers offer extracts labeled epithelium (washed intact skin), pelt (washed or ground pelt of the animal, containing large amounts of serum proteins) and urine. Rats and mice produce a single allergen, Rat n 1 or Mus m 1, that is excreted from the liver and saliva. The hepatic protein is concentrated in the urine and both the urine and salivary sources contaminate the fur or pelt. So it really makes little difference which source is chosen, since the same protein is important in each case. In addition, serum albumin is a minor allergen, generally recognized by less than half of patients allergic to rodents. The allergen extracts are not standardized, so they vary widely in potency, both between manufacturers and between lots from a given manufacturer; but this variation is no greater than that seen with other unstandardized extracts.
Ann Allergy Asthma Immunol. 2004 Aug;93(2):171-8.
Mouse allergen exposure and immunologic responses: IgE-mediated mouse sensitization and mouse specific IgG and IgG4 levels.
Matsui EC, Krop EJ, Diette GB, Aalberse RC, Smith AL, Eggleston PA.
Department of Pediatrics, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA. ematsui@jhmi.eduBACKGROUND: Although there is evidence that contact with mice is associated with IgE-mediated mouse sensitization and mouse specific antibody responses, the exposure-response relationships remain unclear. OBJECTIVE: To determine whether IgE-mediated mouse sensitization and mouse specific IgG (mIgG) and mIgG4 levels increase with increasing Mus m 1 exposure. METHODS: One hundred fifty-one workers at a mouse research and production facility were studied. Exposure assignments were made by linking participants to airborne Mus m 1 concentrations in their respective work areas. Cumulative exposure was estimated by multiplying airborne Mus m 1 concentration by duration of employment. Serum mIgG and mIgG4 levels were quantified by antigen-binding assays, and IgE-mediated mouse sensitization was evaluated by skin prick testing (SPT). RESULTS: Prevalence rates of mouse SPT sensitivity and of high levels of mIgG and mIgG4 were increasingly higher by quintiles of increasing cumulative exposure (P < .01 for SPT, mIgG, and mIgG4). After adjusting for age, sex, and atopy, the log odds ratio (OR) of having positive mouse SPT results was linearly related to cumulative exposure (r2 = 0.87), as was the log OR of having a high mIgG level (r2 = 0.86). Quintile of cumulative exposure was an independent predictor of both SPT sensitivity (OR, 1.7; 95% confidence interval, 1.2-2.5) and a high mIgG level (OR, 1.7; 95% confidence interval, 1.2-2.4).
CONCLUSIONS: IgE-mediated mouse sensitization and mIgG and mIgG4 levels were related to cumulative exposure in a dose-dependent manner. Thus, strategies to prevent allergy to mice should remain focused on reducing mouse allergen exposure.
J Allergy Clin Immunol. 2004 May;113(5):910-5. Related Articles, Links
Mouse allergen exposure and mouse skin test sensitivity in suburban, middle- class children with asthma.
Matsui EC, Wood RA, Rand C, Kanchanaraksa S, Swartz L, Eggleston PA.
Department of Pediatrics, Johns Hopkins University, Johns Hopkins Hospital, CMSC 1102, 600 N. Wolfe Street, Baltimore, MD 21287, USA. ematsui@jhmi.eduBACKGROUND: Exposure to mouse allergen is prevalent in inner-city homes and is associated with an increased risk of mouse skin test sensitivity in inner-city children with asthma.
OBJECTIVE: To determine the distribution of mouse allergen and its relationship to mouse skin test sensitivity in a primarily suburban, middle-class population of asthmatic children. METHODS: Children with asthma, 6 to 17 years old, were recruited from 3 pediatric practices located in counties surrounding the city of Baltimore and from 1 practice located within the city limits. Participants underwent skin prick testing and completed a baseline questionnaire. Their homes were inspected, and settled dust samples were collected for allergen analysis.
RESULTS: Two hundred fifty-seven of 335 (76.7%) participants resided outside the city, and 53.7% had annual incomes >$50,000. Mouse allergen was detected in 74.9% of bedrooms, and 13.1% were sensitized to mouse. Lower maternal education (odds ratio [OR], 2.17; 95% CI, 1.28-3.67), city residence (OR, 5.39; 95% CI, 2.23-13.02), and higher bedroom cockroach allergen levels (OR, 9.61; 95% CI, 1.17-79.03) were independent predictors of high bedroom mouse allergen. The risk of mouse skin test sensitivity increased with increasing bedroom Mus m 1 exposure (OR, 1.43; 95% CI, 1.04-1.96, with each increase in quartile), and dog skin test sensitivity was a strong independent predictor of mouse skin test sensitivity (OR, 7.23; 95% CI, 3.03-17.22)
2/2/05 re: Info re ferret allergy Was there ever any response from Dr. Lockey in regards to the 'Approach to ferret allergy' Q&A below? If not, is there any other information on the subject of immunotherapy treatment for ferret allergies that you are aware of?
I consulted Dr. Lockey again about the question of ferret allergy (as noted in his response below, he did not receive the message in 10/03). Dr. Lockey's comments, just sent to me, are enclosed below.
Sorry, never got the message from anybody. Yes, we have had several ferret-allergic individuals and this case reported in the JACI was among the worst. My answers to the questions: 1) First, no allergenic extract available. 2) Second, avoidance only treatment. 3) Third, as far as I know no cross reactivity with other danders. Ferret is in the mink family and doubt any extract or cross-reactivity to any other known extract. Hope this helps and sorry about the delay.
5/28/04 re: Starting lab for allergies in animals My partners and I are starting an animal diagnostic laboratory in Birmingham , AL and are very interested in starting an allergy reference laboratory for animals to test for southeastern allergens as well as food and flea allergies. We would like to know where to look for information on starting IgE testing and providing immunotherapy.
I assume from your message that your intent is to diagnose relevant allergies in animal populations. Therefore, I consulted a colleague (Dr. Robert Schwartzman) who ran the Allergy Diagnostic Laboratory in the University Of Pennsylvania Vet School until his retirement. Dr. Schwartzman suggested that you contact Dr. Robert Esch in the Greer Labs in Lenoir NC, a sizable allergy products company (877.777.1080 for the division handling veterinary allergy products). He said that Dr. Esch is both knowledgeable and cooperative. You may also want to go to the website of Greer dealing with veterinary issues (veterinary@greerlabs.com).
5/12/04 re: Immunotherapy for allergy to mice, rats Is there an extract available for immunotherapy for allergy to rodents (mice and rats)? This would be for a patient involved in preclinical pharmaceutical research who has an occupational exposure.
I am enclosing below a recent question similar to yours sent to this Ask the Expert program and my response. I enlisted input from Dr. Peyton Eggleston of Johns Hopkins Univ, an expert in the field of allergy to lab animals
I am caring for a pharmaceutical research scientist who has worked for sixteen years in a building where there is no animal handling facility, but where lab rats and mice are brought in their cages and parked for hours at a time. He has allergic rhinitis to both seasonal and perennial common allergen. He also has airflow obstruction which doesn't respond to nebulized beta-agonists or a short course of oral glucocorticosteroids. I am referring him to a pulmonologist, but will continue to care for the atopic portion of his respiratory care. I am interested in any research trials of immunotherapy to mouse or rat. I am also interested in what other similarly affected scientists have done, in detail, to reduce the respirable allergens in such a lab, and whether symptoms were actually improved. Naturally I could contrive an allergen reduction recommendation based on our experience with cats in the home, but if others have tried and failed to benefit patients I would be grateful to know this in advance.
Response
To my knowledge, there are no FDA-approved commercial mouse or rat extracts for immunotherapy. I consulted Dr. Peyton Eggleston of Johns Hopkins Univ, an expert in the area of allergy to lab animals. Dr. Eggleston's response is now enclosed below.
You ask two questions. There are almost no data on immunotherapy to laboratory rodents. Wan Virginian (JACI1980; 65:413) described the immunologic changes in a group of workers receiving immunotherapy and mention that they were clinically improved. That is about it. More studies have been published with cats and dogs, and here it can be shown that immunotherapy will reduce the increase in acute symptoms on exposure-but they do not address long term changes. What these studies show is that actively treated patients can on average triple the 10-20 minutes exposure that usually results in intolerable symptoms. This offers little benefit to persons living with a pet, but might be helpful in someone with occupational exposure.
There is a lot of information regarding specific recommendations to reduce workplace exposure-these were summarized in two reviews:
Bush et al JACI 1998;102:100-112.and Bush and Stave ILARJournal 2003;44:28-51.
Another excellent description of reducing exposure at a large mouse research facility is in Schweitzer et al Comparative Medicine 2003;53:487. What all of these say is to use personal protective gear (gown, gloves, mask) at all times and to keep them clean. After contact with the animals or the areas of high exposure such as vivaria, cage cleaning rooms or animal surgeries, contaminates clothing and gloves. Gowns should be washed daily and gloves changed frequently; never touch the face with a gloved hand. Handling animals for surgery and experiments on a laminar flow table helps a great deal with individual exposure. In vivaria, keeping the animal density as low as possible, housing them in negatively-pressurized, laminar flow cage racks with HEPA filters is helpful. Increasing ventilation rates is not helpful. At the same time, proper ventilation with limited recirculation, outside intakes and exhausts are a basic approach that is an essential design feature; proper maintenance of the system is equally important. There have not been controlled studies of the effects of implementing these avoidance procedures, but airborne allergen measures have been reported and exposure is reduced by about 90%.
10/15/03 re: Approach to ferret allergy Any advice regarding a patient who knows he is allergic to his ferrets and refuses to remove them from his environment? I am not aware of any ferret extract but does ferret cross reaction with any other dander/pelt i.e cat or rodents? This gentleman is already on a maintenance regimen with respect to pollens and does very well with minimal need for medication for his upper airway symptoms, but since the introduction of 2 pet ferrets he is back to daily nasal steroids and antihistamines. Any suggestions? In the only report about ferret allergy of which I am aware, Dr. Richard Lockey's group on Tampa described studies of a patient who had asthma reactions on 2 occasions when washing a pet ferret (the second reaction being very severe). Their studies showed that skin test and in vitro allergic reactivity was directed mainly against several protein fractions in the urine more than in their "home made" crude extract of ferret hair (JACI 2001;107:927). The presence of sizable amounts of allergens in the urine is common in rodents.The authors claimed that this was the first report of studies of ferret allergy. They suggested possible cross-reactivity between ferret and mink but did not mention any cross-reactivity to other animal species. Therefore, I think that one cannot count on protection against presumed ferret allergy from any of the standard animal allergen immunotherapy programs. A practical suggestion would be to avoid personal contact with the ferret and any material contaminated with ferret urine (for the reason given above). I have asked Dr. Lockey for his input in this matter. However, he is apparently out of town at present. If we receive any information from him, it will be forwarded to you. 7/7/03 re: Cat pelt vs cat fur extracts used in immunotherapy I am a member of the AAAAI - I have a question on allergen extracts. We are unable to locate a supplier for the cat pelt that we have been using for immunotherapy. We have contacted Greer, Hollister-Stier/Bayer, Center/ALK without success.
1) Do you know of a supplier?
2) Could we switch from cat pelt to cat hair? If so, do we need to decrease the dose ten fold, and then slowly increase to the previous dose?I referred your question to Dr. Peyton Eggleston of the Johns Hopkins Medical Institutions, a leading expert in the area of cat allergy. His response is enclosed below. I contacted the questioner directly by E mail. He was right- 1) there are currently no pelt (ground up cat pelt) extracts and 2) the new standardized epithelia or fur extracts contained much higher proportions of Fel d 1. I recommended that he begin the cross-over to these newer extracts with a 1:100 dilution of the planned top dose (usually about 5ug Fel d1) I also gave him Hal Nelson's reference to standardized extracts in the JACI, vol 106.11/11/02 re: Efficacy of Allerpet in reducing cat allergen dissemination I am a Family Nurse Practitioner and I have a question regarding a product that was brought to my attention called "Allerpet." Do you know how effective this would be for a patient to use on 3 household cats (indoor living)? Have there been any studies done on products such as this? Any literature that you are aware of would be helpful.
A careful study by a group in the Henry Ford Hospital system in Detroit, MI showed no significantly greater efficacy of Allerpet than placebo treatment of cats in reducing disseminated levels of cat allergen (see enclosed abstract). Two subsequent reports have also found no impressive reduction of cat allergen dissemination by Allerpet treatment of the household cat (see enclosed titles). My impression is that experts in environmental control of allergens are unenthusiastic about use of the Allerpet product.
J Allergy Clin Immunol 1995 Jun;95(6):1164-71
Cat shedding of Fel d I is not reduced by washings, Allerpet-C spray, or acepromazine.
Klucka CV, Ownby DR, Green J, Zoratti E.
Henry Ford Health System, Detroit, Mich., USA.
BACKGROUND: No published studies have compared the effectiveness of several treatments proposed to reduce cat allergenicity. Cat washing studies demonstrating efficacy involved very small sample sizes or infrequent washings. Allerpet-C (Allerpet, Inc., New York, N.Y.), a widely advertised topical spray, and acepromazine, a tranquilizer advocated as efficacious in subsedating doses, have never been scientifically studied.
OBJECTIVE: We compared the effects of cat washing, Allerpet-C spray, and acepromazine with that of no treatment on the shedding of the primary cat allergen, Felis domesticus I by cats.
METHODS: In a blinded, comparative, controlled study, we measured the amounts of Fel d I shed during an 8-week treatment period with a sample of 24 female mongrel cats randomly assigned to four groups; one group received weekly distilled water washings, one received weekly Allerpet-C spray applications, one received daily oral acepromazine, and one had no treatment (control). Thirty-minute, twice-weekly air samples were collected from each cat with a laminated plastic-acrylic chamber and air sampler. RESULTS: One-sample, two-sided t tests comparing baseline to final-week measurements revealed no significant change in Fel d I within each group (mean change +/- SD: washing; 487.6 +/- 1896.4 mU per 30 minutes, p = 0.63; Allerpet-C spray, 429.2 +/- 871.6 mU per 30 minutes, p = 0.46 acepromazine; -620.6 +/- 1031.2, p = 0.52 per 30 minutes). Furthermore, analysis of covariance revealed no significant change in Fel d I levels between groups (p = 0.72).
CONCLUSIONS: Out data do not show significant reductions in Fel d I shedding as a result of any of these treatments. Therefore we cannot recommend them to patients allergic to cats.
Perzanowski MS, Wheatley LM, Avner DB, Woodfolk JA, Platts-Mills TA. The effectiveness of Allerpet/c in reducing the cat allergen Fel d 1.
J Allergy Clin Immunol. 1997 Sep;100(3):428-30.
2: Wood RA. Indoor allergens: thrill of victory or agony of defeat?
J Allergy Clin Immunol. 1997 Sep;100(3):290-2.12/27/01 re: Low allergenic cats I would like to know of any research that has been done on breeds of cats that do not cause allergic reactions in people that are sensitive to cats, in particular the domestic breed known as the Bengal cat.
I have not found any information about Bengal cats specifically but my understanding is that the major cat allergen ( Fel d 1) is shed by all cat breeds. Males tend to shed more allergen than females. It used to be thought that short-hair cats caused less allergy problems. However, that is not always the case since Fel d 1 is also found in the hair follicles, skin and saliva. The latter is an important source since many cats lick themselves frequently. The saliva dries on the surface of the hairs and is shed into the environment, particularly when the cat rubs itself against objects (very common). Cat hairs have a consistency that makes them adhere to floor coverings, stuffed furniture, bedding, etc.
Obviously, the best approach for a cat sensitive individual is to keep cats out of dwellings the patient spends much time in. When this is not possible, some "partial remedies" may have some beneficial effects (although definitely less than complete avoidance):
1) Washing the cat once a week will reduce the amount of cat allergen in the environment. However, many cats will not tolerate such frequent washing.
2) Confine the cat to one room (not the patient's bedroom). Removal of rugs/carpets and overstuffed furniture from that room
3) Use of an adequate HEPA-filtration device in the room in which the cat resides. Use of a tightly fitting HEPA filter-equipped vacuum cleaner. These measures will reduce airborne levels of Fel d 1. However, conflicting findings have been reported about the degree of clinical benefit derived from these approaches.
In any event, it must be explained carefully to the patient that it may take months, even after removal of the cat from the house, to see an impressive decrease in cat allergen-induced symptoms (because it takes that long for adequate removal of pre-existent cat allergens with the usual cleaning approaches).
Reference: Current Allergy Reports 2001; 1: 461-65
12/13/00 re: Guinea pig allergy A patient exhibits a moderate allergic response to guinea pigs. Do you think they would respond in a similar manner to the hairless form of this breed, commonly known as "skinny pig." Although I do not have any information specifically dealing with "skinny pigs," I would suspect that your patient would likely have allergic reactions to these animals if they are biologically related to standard guinea pigs. It has been known for some time that the allergenic substances in rodents are present in ample amounts in the saliva and urine as well as on the skin. In fact, some studies have suggested that much of the allergenic properties of the hair of such animals comes from saliva licked on the hair (see below abstract). A common finding in lab animal-sensitive humans is that they react to the urine-soaked bedding material in the cages of the suspect animals but not to fresh bedding material not yet put in animal cages. It is thought that the urine partially dries in the bedding material and is then disseminated into the air when the animal scrambles in the cage and/or the bedding is removed during cleaning of the cage. Allergy to guinea pigs: II
Identification of specific allergens in guinea pig dust by crossed radio-immunoelectrophoresis and investigation of the possible origin.
Walls AF, Newman Taylor AJ, Longbottom JLAn extract of dust from the air-vent filters of a room housing guinea pigs was analyzed by quantitative immunoelectrophoretic procedures and compared with extracts of various materials derived from guinea pigs. Crossed radio-immunoelectrophoresis (CRIE) of the dust, performed with sera from twenty asthmatic patients who were positive by skin testing and RAST to guinea pig extracts, identified fourteen IgE-binding constituents. Although responses varied, most sera reacted with four particular allergens, antigens 2, 3, 10 and Sl. The numbers of allergens recognized by individual patients correlated with the RAST score, but not with total serum IgE. All seventeen dust constituents detected by crossed immunoelectrophoresis (and all four major allergens), were also present in extracts of guinea pig dander, fur, saliva and urine; several of these components were absent in an epithelial extract, and there were even less in preparations of shaved pelt, serum or feces. None of the dust extract antigens were detected in materials used in animal husbandry, dust samples from rooms without guinea pigs, or a D. pteronyssinus extract. These findings suggest that inhalant allergens may be derived predominantly from material shed from the guinea pig coat after contamination with saliva, and possibly to a lesser extent, urine.
9/5/00 re: Is formaldehyde preserved cat material allergenic I have a cat allergy, among others and have a few labs where we dissect cats. Can the cat dander affect my asthma if the animal is dead and submersed in formaldehyde? Should I participate in this lab? I posed this question to my allergist and she had no information for me on this. Can you help to answer my question? Here is some info on myself. I am a 30 y/o female with asthma and allergies. I am currently receiving allergy shots every 2 weeks for multiple allergies. I am taking Serevent, Flovent, Singulair and Flonase. Based upon past experimental studies, one would expect that thorough incubation of the cat in formaldehyde would denature the allergenic proteins sufficiently so that at least those on the surface would not elicit allergic reactions in sensitive individuals. In fact, one group previously developed preparations of allergens pre-incubated with glutaraldehyde (a compound in the same family as formaldehyde) which they claimed would induce protective responses when injected in sensitive individuals without triggering allergic reactions. It should be noted that much of the allergenic material in cats is concentrated in the saliva. In fact, some investigators have concluded that much of the material in "cat hair" to which cat-sensitive people react is actual dried saliva present on the coat of the cat from extensive licking (which is very common in cats, as you know).. I would assume that the formaldehyde would permeate into the internal organs as well, denaturing proteins there, including the salivary glands/saliva. 3/27/00 re: Control measures for dog allergen A patient of mine has asthma and two golden retriever dogs. She refuses to give up the dogs. what measures can be taken to minimize the allergenic effect of the dogs? I should emphasize that removal of the dog from the home is the best approach (see enclosed review by me in our Current Literature Section). If that is not feasible:
- Keep the dog out of patient's bedroom with the door closed (see enclosed abstract).
- Wash the dog twice a week (see enclosed abstract). Note that airborne allergen levels reduced only modestly.
- Use of adequately powered HEPA filter (see enclosed abstract and my review).
- Remember that there will be residual dog allergen on the patient's clothing, bedding, furniture. Unfortunately, the dog allergen is more resistant to high temperature (dry or wet) that are dust mite allergens. Nevertheless washing clothing at >120° F is worth trying when feasible.
- Also, if the patient is very dog allergic, the patient should avoid, when feasible, close contact (e.g. schoolyard games) with children from homes with multiple dogs. The clothing of such children may carry a fair amount of dog allergen.
Air filtration and airborne dog allergen
SUMMARY - It is generally agreed that removal of pets from the home is the best approach for patients allergic to such animals. However, may pet lovers will not get rid of their pets. Therefore, Green et al of the Wythenshawe Hospital in Manchester, UK investigated the effects of an HEPA air filtration device on airborne levels of the dog allergen Can F1 in 9 homes containing a dog, kept predominantly in one room. Although Can F 1 levels (assessed by a high volume sampler at hourly levels) subsequently decreased in the room not occupied by the dog whether the room HEPA filtration unit was on or not, the decreases were greater (90%) then the filtration unit was operating. In baseline measurements, the airborne Can F1 levels were 3.8 fold higher in the room occupied by the dog. Subsequently these levels in the dog-occupied room decreased only when the HEPA filtration unit was on.
REFERENCE - Allergy 1999;54:484-88
EDITOR'S COMMENTS - These encouraging findings differ from that reported by Wood et al in studies of HEPA filtration on airborne cat allergen levels where the reduction in Fel D1 levels were not reduced enough to be clinically helpful (See previous review in this Current Lit. section) The reasons for the different findings in these 2 studies are not clear - different filtration device? sampling methods? or nature of the allergen? In any event, avoidance seems preferable, even if limited to keeping the pet out of rooms used frequently by the patient.J Allergy Clin Immunol 1999 Apr;103(4):581-5
Washing the dog reduces dog allergen levels, but the dog needs to be washed twice a week.
Hodson T, Custovic A, Simpson A, Chapman M, Woodcock A, Green R
North West Lung Centre, Wythenshawe Hospital, Manchester, UK.
BACKGROUND: Many asthmatic patients allergic to dogs refuse to part with their dog, and it is essential to develop techniques for lowering exposure with a dog in the home.OBJECTIVE: This study investigated the effect of dog washing on the subsequent recovery of Can f 1 from dog hair clippings and on the airborne allergen over a 7-day period.
METHODS: Dogs, which had not been washed for at least the previous 3 weeks, were washed with a hand-held shower and proprietary shampoo. Hair clippings and dander samples from 25 dogs were collected before and immediately after washing. After these initial studies, 16 dogs had a small tuft of hair clipped from the collar or spinal area before washing and then daily for the next 7 days. Air sampling was performed in 5 homes, and the air samples were collected (airflow rate, 9 L/min) over an 8-hour period per day on 10 consecutive days (3 days of baseline sampling before washing and then 7 consecutive days after washing). Can f1 level was measured by using 2-site ELISA.
RESULTS: Washing significantly reduced recoverable Can f 1 from clippings (84% reduction: from 73 microg/g to 12 microg/g [geometric mean]; P <.0001) and from dander samples (86% reduction: from 347 microg/g to 50 microg/g [geometric mean]; P <.0001). There was a significant reduction in Can f 1 levels in dog hair over the observed 8-day period (F = 18.4, P <. 0001). By using a multiple comparison test, this observed significance was found to be due to the difference between the baseline levels and those on days 1 and 2 after washing, with no difference in the baseline Can f1 compared with days 3 to 7. Airborne Can f1 levels showed a downward trend, which reached statistical significance when the data were grouped into 3 sampling periods as follows: baseline (ie, mean of 3 days before sampling) was compared with days 1 to 4 after washing (41% reduction, 95% CI 13%-60%) and days 5 to 7 after washing (61% reduction, 95% CI 2%-84%; P =.014).
CONCLUSIONS: Washing the dog reduces recoverable allergen from dog hair and dander. The dog needs to be washed at least twice a week to maintain the reduction in recoverable Can f1 from its hair. Washing the dog achieves a modest reduction in the level of airborne Can f1 in homes with a dog.
J Allergy Clin Immunol 1999 Aug;104(2 Pt 1):447-51
Clinical effects of air cleaners in homes of asthmatic children sensitized to pet allergens.
van der Heide S, van Aalderen WM, Kauffman HF, Dubois AE, de Monchy JG
Department of Allergology, Clinic for Internal Medicine, Beatrix Children's Hospital from the University Hospital Groningen, Groningen.
BACKGROUND: Exposure to cat and dog allergens is very common in the Western World and is a serious cause of asthma in sensitized subjects.OBJECTIVE: We sought to study the clinical effects of air cleaners in living rooms and bedrooms of asthmatic children sensitized to cat or dog allergens.
METHODS: Twenty asthmatic children sensitized to pet allergens (cat/dog) and with an animal at home participated in a double-blind, placebo-controlled, cross-over study in which the effects of air cleaners placed in the living room and bedroom for 3 months were compared with the effects of sham air cleaners. Before and after each study period, lung function, airway hyperresponsiveness (adenosine monophosphate), and peak flow variation were recorded. Cat and dog allergen levels were assessed in the filters of the air cleaners.
RESULTS: After a 3-month intervention with active air cleaners, airway hyperresponsiveness decreased significantly, showing a 1.2 doubling dose increase of PC(20 )adenosine (P =.003). Peak flow amplitude also decreased (P =. 045). Substantial amounts of airborne cat and dog allergen were captured by the air cleaners in living rooms and bedrooms as well. Allergen levels in floor dust were not changed.
CONCLUSION: In young asthmatic patients sensitized and exposed to pets in the home, application of air cleaners in living rooms and bedrooms was accompanied by a significant improvement in airway hyperresponsiveness and a decrease in peak flow amplitude.
Allergy 1999 May;54(5):484-8
The effect of air filtration on airborne dog allergen.
Green R, Simpson A, Custovic A, Faragher B, Chapman M, Woodcock A
North West Lung Centre, Wythenshawe Hospital, Manchester, UK.
BACKGROUND: Effective methods of reducing dog allergen are required to help alleviate symptoms in asthmatic patients sensitized to dog who refuse to part with their pet. The aim of this study was to investigate the use of the high efficiency particulate air (HEPA) filter air cleaner to reduce airborne Can f1 in homes with a dog.METHODS: The effect of a HEPA air cleaner was investigated in nine homes with a dog. Samples were collected from two rooms of each house concurrently, one of which contained the dog, on two separate days (active day - HEPA air cleaner on - and control day). Eight consecutive 1-h samples were collected from each room with a high-volume air sampler (airflow rate 60 l/ min). Can f1 was determined by monoclonal-polyclonal antibody-based ELISA.
RESULTS: Baseline airborne Can f1 levels were 3.8-fold greater when sampling was performed with a dog in the room (GM 27.1 ng Can f1/m3, range 2.63-329) than when the dog was elsewhere in the house (GM 7.1 ng Can f1/m3, range 0.69-27.2). When the dog was elsewhere in the house, airborne Can f1 levels fell on both active and control days, but the magnitude of the reduction was significantly greater on the active days (P<0.05), and was approximately 90% from baseline. With the dog in the room, a significant fall in airborne Can f1 was observed only on active days (75% from baseline), but not on control days (active vs control P<0.001).
CONCLUSIONS: HEPA air cleaners reduce airborne Can f1 in homes with dogs. Furthermore, preventing the access of the dog to the bedroom and possibly the living room may reduce the total allergen load
6/29/99 re: Efficacy of IT for allergy to horses Is extract available for immunotherapy for allergy to horses? If so, is/are there any studies confirming efficacy? What doses and what schedule? Although I have seen occasional patients given immunotherapy (IT) with crude horse dander extracts by other physicians, I have not done this myself, even though I have treated a number of veterinary school personnel. I know of no systematic study of such IT after review of 2 monographs about IT. There is some older literature (Ann Allergy 1976;36:165-73) describing use of an alum pyridine dander extract of uncertain efficacy (no longer available) in an uncontrolled manner. Because of the potential for excess local (and possible systemic) reactions to crude animal extracts, I would personally be somewhat leery and certainly very cautious about attempting horse dander IT. (There are no standardized preparations ofv horse antigenic extracts to my knowledge). Avoidance measures are much preferred.
03/30/97 re: Cat allergy A young woman is allergic to cats but has a cat as a pet which she won't give up. She takes Claritin once a day and she keeps the cat out of her closed door bedroom at all times. She finds this generally satisfactory but occasionally has allergic symptoms. Is there anything else to recommend to her? Other measures to reduce exposure to cat allergen:
- There is a high concentration of Fel 1 (the major cat allergen) in cat saliva, and cats frequently groom themselves by licking. Therefore, frequent washing of the cat will reduce dissemination of cat allergen. Some cats do not like to be bathed; however, devices to do this have been marketed.
- HEPA filters in an air filtration system and a high quality vacuum cleaner should reduce airborne cat allergen particles.
If the patient becomes more symptomatic with continued exposure and still refuses complete avoidance one can consider allergy injection treatment with standardized cat extract.
I suggest that you contact a certified allergist-immunologist in your region to assist you in managing this patient's problems. To get a list of such specialists in your region, contact the AAAAI Hot Line at 800-822-2762.
