Hypersensitivity Disorders 2018-2020 Flashcards
1
Q
- Acute contact dermatitis caused by chromium (VI) (CrVI) has long been a
recognized occupationalproblem, especially from exposure to:
A. baking yeast.
B. hair dyes.
C. mobile phones.
D. wet cement.
A
- D, wet cement, p. 566.
During the construction of the Channel tunnel connecting continental Europe with Britain, the prevalence of chromate allergy in cement workers was reported to be as high as 17%. Subsequently, the European Union regulated the content of chromium in cement, and sensitization to chromate in construction works has since declined. No such legislation exists in the United States. Other sources of chromate exposure include contact with leather tanned with salts containing chromate and this has become increasingly recognized.
Chapter 35: Contact Dermatitis
Middleton’s Allergy Principles and Practice, 8th Edition
2
Q
- Irritant contact dermatitis is the most common form of contact dermatitis in the population. An irritant will cause direct injury to the skin in any person, if applied in a sufficient concentration for a sufficient amount of time, without prior sensitization or immunological memory. Irritants include wet work. “Wet work” is defined when individuals have their skin exposed to liquids longer than:
A. 1 hr per day, or use occlusive gloves longer than 1 hr per day, or clean the hands very often (eg 10 times per day or less, dependent
B. 2 hrs per day, or use occlusive gloves longer than 2 hrs per day, or clean the hands very often (eg 20 times per day or less, dependent
C. 3 hrs per day, or use occlusive gloves longer than 3 hrs per day, or clean the hands very often (eg 30 times per day or less, dependent
D. 4 hrs per day, or use occlusive gloves longer than 4 hrs per day, or clean the hands very often (eg 40 times per day or less, dependent
A
2. B. 2 hrs per day, or use occlusive gloves longer than 2 hrs per day, or clean the hands very often (eg 20 times per day or less, dependent, p. 567. According to the German regulation of hazardous substances at the workplace, “wet work” is defined when individuals have their skin exposed to liquids longer than 2 hrs per day, or use occlusive gloves longer than 2 hrs per day, or clean the hands very often (eg 20 times per day, or less dependent) if cleaning procedure is aggressive.
3
Q
- Topical agents causing phototoxic reactions particularly include plants containing
furocoumarins, such as:
A. Avocado, blueberries, strawberries
B. Celery, carrot, and citrus fruits
C. Spinach, red cabbage, brussels sprouts
D. Zucchini, cucumbers, squash
A
- B, Celery, carrot, and citrus fruits, p. 567.
Topical agents causing phototoxic reactions particularly include plants containing
furocoumarins, such as celery, carrot, and citrus fruits.
4
Q
- Which syndrome - a form of systemic contact dermatitis - can occur when sensitized
persons are exposedto allergens from routes other than skin exposure, such as orally,
intravenously, or by inhalation?
A. Baboon syndrome
B. Hippopotamus syndrome
C. Lemur syndrome
D. Rhinoceros syndrome
A
- A, Baboon syndrome, p. 568.
Systemic contact dermatitis may occur when sensitized persons are exposed to allergens from
routes other than skin exposure, such as orally, intravenously, or by inhalation. Clinical
manifestations may include flare-ups of dermatitis in previous sites or of positive patch test
site reactions, as well as vesicular hand eczema and “baboon syndrome,” which refers to a
well- demarcated rash on the buttocks, genital area, and thighs. Causes commonly include
metals such asnickel, cobalt, chromate, gold, and mercury. In certain case, treatment includes
dietary avoidance of the particular metal.
5
Q
- Contact dermatitis can be differentiated from irritant dermatitis based on which of the
following?
A. Evidence of urticarial reaction immediately upon contact with the skin
B. No involvement of part of the body that does not come in contact with the allergen
C. Poorly defined borders
D. Well defined borders
A
- C, Poorly defined borders, p. 568.
Unlike in irritant contact dermatitis, the borders of the lesions in allergic contact dermatitis
(ACD) are poorly defined. In ACD, additional lesions can appear on other parts of the body
that have not come into contact with the allergen (a phenomenon known as secondary
spread).
6
Q
6. What is an effective in treating chronic contact dermatitis, particularly that affecting the hands? A. Azathioprine B. Laser therapy C. Mycophenolate mofetil D. Phototherapy
A
- D, Phototherapy, p. 572.
In chronic contact dermatitis, particularly affecting the hands, phototherapy has proved
effective. Currently, therapy mainly consists of either UVB light or psoralens plus UVA light
(PUVA) applied topically or in a bath. With long-term therapy, the potential carcinogenic risk
must be considered.
7
Q
- In irritant contact dermatitis of the hands, the predominant areas involved include:
A. the fingernails initially, then the knuckles of the fingers.
B. the palmar areas of the hands initially.
C. the web spaces initially, the dorsal aspects of the hands and fingers.
D. the wrist areas
A
- A, the web spaces initially, the dorsal aspects of the hands and fingers., p. 568.
It often is not possible to distinguish the clinical findings in ICD from those in ACD. Classically,
the first signs of ICD are dry and slightly scaly skin, with increasing redness and lichenification
after prolonged or repeated exposure to an irritant(s). This may be followed by formation of
fissures, also known as rhagades. Itching is generally not as severe as in ACD. On thehands, the
predominant areas involved include the web spaces initially.
8
Q
- High molecular weight (HMW) compounds are mostly protein or polysaccharides and
act as completeantigens directly provoking an IgE-mediated response. Which of the
following agents is a HMW agent?
A. Cereals
B. Isocyanates
C. Metals
D. Wood dusts
A
- A, Cereals, p. 973, Table 59-2.
Cereals are high-molecular weight-agents that cause immunologic occupation asthma, while
isocyanates, metals (like chromium, nickel, cobalt, and platinum), and wood dusts are all lowmolecular-weight agents.
Chapter 59: Occupational Allergy and Asthma
Middleton’s Allergy Principles and Practice, 8th Edition
9
Q
- Which of the following agents is the most frequent and most often reported cause of
occupational asthma in Western countries?
A. Acrylates
B. Baking products
C. Diisocyanates
D. Wood dust
A
- B, Baking products, p. 981.
Baking products are the leading cause of occupation in most Western countries with 0.8-2.4
cases per 1000 exposed workers and a cumulative incidence rate of 12.4% for IgE mediated
sensitization to bakery allergens, 8.4% for OR and 6.1% for occupational asthma.
10
Q
3. What is the single most important risk factor for occupational asthma? A. Atopy B. Exposure C. Rhinoconjunctivitis D. Smoking
A
- B, Exposure, p. 974; Table 59-4.
The intensity of exposure to sensitizing agents is currently the most well-characterized
and most important environmental risk factor for the development of occupational
asthma.
11
Q
4. What agent should you suspect in an automobile worker with occupational asthma who works in finish coating? A. HDI (hexamethylene diisocyanate) B. LDI (lysine diisocyanate) C. MDI (methylene diphenyl diisocyante) D. TDI (toluene diisocyanate)
A
4. A, HDI (hexamethylene diisocyanate), p. 982. Hexamethylene diisocyanate (HDI) as it is used extensively in spray paints.
12
Q
5. Patients with occupational asthma and exposure to which of the following agents would have the best prognosis? A. HDI (hexamethylene diisocyanate) B. LDI (lysine diisocyanate) C. MDI (methylene diphenyl diisocyanate) D. TDI (toluene diisocyanate)
A
- A, HDI (hexamethylene diisocyanate), p. 983.
Occupational asthma due to HDI seems to carry a better prognosis than
occupational asthma due to TDI and MDI.
13
Q
- Which of the following conditions is characterized by the lack of a latency period and
immunologicsensitization, and occurs after a single massive irritant exposure?
A. Acute respiratory distress syndrome
B. Reactive airway dysfunction syndrome
C. Work-related asthma
D. Work-exacerbated asthma
A
- B, Reactive airways dysfunction syndrome, p. 970.
Reactive airways dysfunction syndrome refers to a type of occupational asthma without latency
and immunologic sensitization, occurring after a single massive irritant exposure with
consequent severe airway injury,and resulting in persistent airway inflammation and
nonspecific bronchial hyperresponsiveness.
14
Q
- The epidemiology of occupational asthma is challenging. Which of the following statements is
true?
A. Data generated by voluntary notification schemes rely mainly on confirmatory concrete data.
B. Medicolegal statistics from compensation boards may overestimate prevalence.
C. Occupational rhinitis is known to be equally as common as occupational asthma.
D. Population surveys minimize survivor bias but lack confirmatory testing data.
A
- D, Population surveys minimize survivor bias, but lack confirmatory testing data, p. 972.
Data generated by voluntary notification schemes rely on the physician’s diagnostic opinion and
no confirmatory tests are required. Medicolegal statistics may underestimate the true
incidence of occupational asthma because not everyone applies for compensation. Population
surveys minimize survivor bias but arelimited by the lack of confirmation testing. Occupational
rhinitis is 2-4 times more common than occupational asthma.
15
Q
- Sputum eosinophils have been used as an objective measure of airway inflammation in
occupational asthma. What is thought to be the ideal timeframe for sputum collection to
check for sputum eosinophils?
A. 1 hour post exposure
B. 3-5 days post exposure
C. 7-10 days post exposure
D. 7-24 hours post exposure
A
- D, 7-24 hours post exposure, p. 979.
The best timing for the collection of induced sputum with respect to exposure to occupational
agents is likely to be 7-24 hours after exposure.
16
Q
9. Exposure to which product is associated with work-related anaphylaxis in people who work in nail salons? A. Aldehydes B. Latex C. Methacrylates D. Terachlorophtalic acids
A
- C, Methacrylates, p. 978 and Table 59-2.
The answer is methacrylates. Acrylates are low molecular weight agents found in sculptured
fingernails which can result in immunologic reactions.
17
Q
10. Occupational asthma related to western red cedar is due to exposure to which of the following? A. Bromelain B. Carmine C. Plicatic acid D. Trimellitic acid
A
- C, Plicatic acid, p. 983.
Plicatic acid is present in western red cedar and in small amounts in eastern white cedar.
Plicatic acid has been shown to induce specific bronchial reactions on bronchial challenge
testing in exposed workers with a history compatible with occupational asthma.
18
Q
- What is the name for the eosinophil breakdown products that may be visible by
microscopy in the mucus of asthmatic patients?
A. Birbeck granules
B. Calcium oxalate crystals
C. Charcot-Leyden crystals
D. Curschmann crystals
A
- C, Charcot-Leyden crystals, p. 990-991.
Charcot-Leyden crystals are crystals derived from lysed eosinophils. They may be found in
mucus or mucus plugs and are one of several inflammatory changes that accompany severe
asthma. See Figure 60-8D for a photograph of Charcot-Leyden crystals
Chapter 60: Pathology of Asthma
Middleton’s Allergy Principles and Practice, 8th Edition
19
Q
2. What is the name for the distinctive spiral formations that may be found on microscopy in mucus of asthmatic patients? A. Azurophilic granules B. Charcot-Leyden spirals C. Curschmann spirals D. Döhle bodies
A
- C, Curschmann spirals, p. 990-991.
Curschmann spirals are distinctive spiral formationsthat may be found in mucus or sputum and
are associated with inflammatory changes of severe asthma.See Figure 60-8C for a photograph
of a Curschmann spiral.
20
Q
- A 30-year-old female presents as a new patient to Allergy and Immunology clinic. She
reports a history of cough, chest tightness, and wheezing that worsens when she exercises,
has an upper respiratory infection, or is around cats. She wakes up at night with these
symptoms approximately three times per week. She was prescribed an albuterol inhaler by
her primary care physician and reports that her symptoms are relieved by its use, but she does
feel the need to use it more days thannot. Spirometry reveals FEV1 68% predicted. A sputum
sample is obtained and exhaled fraction of nitric oxide is measured.
Which of the following clinical findings suggests that she would be likely to respond well to
treatment with corticosteroids?
A. Abundant sputum neutrophils
B. Elevated exhaled fraction of nitric oxide
C. Few or no sputum eosinophils
D. FEV1 less than 80% predicted
A
- B, Elevated exhaled fraction of nitric oxide, p. 994.
Airway epithelial cell nitric oxide production is increased in asthmatic inflammation.
Measurement of the fraction of exhaled nitric oxide (FeNO) is considered a marker of
eosinophilic asthma and may predict response to steroid treatmentin non-eosinophilic asthma.
High levels of neutrophils or few or absent eosinophils in sputum may be associated with a poor
response to corticosteroids. FEV1 may be reduced in either corticosteroid-responsive or
corticosteroid-resistant asthma.
21
Q
4. Corticosteroids have which of the following effects? A. Inhibit eosinophil apoptosis B. Inhibit neutrophil apoptosis C. Promote neutrophil apoptosis D. Trigger mast cell degranulation
A
- B, Inhibit neutrophil apoptosis, p. 992.
Corticosteroids selectively inhibit apoptosis of neutrophils and promote apoptosis of
eosinophils. Patients with asthma may develop neutrophilic inflammation in part because of
corticosteroid treatment, though neutrophilic inflammation may also be promoted by Th17 type
CD4+ T lymphocyte production of cytokines such as IL-17A.
22
Q
5. Which of the following is a chemoattractant that attracts eosinophils to the airway mucosa in asthma? A. CXCL5 B. CXCL7 C. CXCL8 D. CCL2
A
- A, CXCL5, p. 992.
CXCL5 is a chemoattractant present in the airway mucosa during asthma exacerbations. Its
presence correlates with increased numbers of eosinophils. The other answers listed are
chemokines that attract other types of cells of the immune system.
23
Q
- Which of the following cytokines is produced most abundantly by CD4+ T lymphocytes in
allergic asthmatic airway inflammation?
A. Granulocyte-macrophage colony-stimulating factor
B. IL-12
C. Interferon gamma
D. Thymic stromal lymphopoietin
A
- A, Granulocyte-macrophage colony-stimulating factor, p. 987.
In allergic asthma, CD4+T lymphocytes play a key role in airway inflammation and most exhibit a
Th2 profile of cytokine secretion with production of IL-4, IL-5, IL-9, IL-13, and granulocytemacrophage colony-stimulating factor (GM-CSF). Thymic stromal lymphopoietin is related to
Th2 differentiation of CD4+ T lymphocytes and is secreted by epithelial cells and keratinocytes,
notby Th2-type CD4+ T lymphocytes. Interferon gamma and IL-12 areTh1-type cytokines.
24
Q
7. Which of the following viruses has been associated with asthma exacerbations? A. Human rhinovirus species A B. Human rhinovirus species B C. Human rhinovirus species C D. Parainfluenza virus
A
- C, Human rhinovirusspecies C, p. 992.
Viral infections are a common trigger for asthma exacerbations and may enhance the
inflammatory response to allergen exposure. Rhinoviruses are the most common viruses to be
implicated in asthma exacerbations and human rhinovirus species C (HRV-C) is a subgroup of
rhinovirus that is particularly associated with asthma exacerbations
25
Q
1. Which of the following would you expect to be a cause of a subacute cough in adults? A. Allergic rhinitis B. Common cold C. Post-infectious cough D. Smoking
A
- C, Post-infectious cough, p. 1032, 1035.
Subacute cough has a duration of 3-8 weeks. Of the listed choices, only post-infectious cough
is expected to fit that duration. The common cold is a cause of acute cough, and both smoking
(via chronic bronchitis) and allergic rhinitis can lead to a chronic cough.Chapter 63: Approach to Patient with Chronic Cough
Middleton’s Allergy Principles and Practice, 8th Edition
26
Q
2. In children, to diagnose chronic cough, symptoms must be present for at least how long? A. 2 weeks B. 4 weeks C. 6 weeks D. 8 weeks
A
- B, 4 weeks, p. 1032.
In children, cough is defined as acute (< 4 weeks) or chronic (> 4 week). Subacute cough is
not defined in children.
27
Q
- After ruling out smoking and ACE-inhibitor use in a patient with a chronic cough, what is
the next best step in management?
A. Empiric treatment with antihistamines, PPI, and bronchodilator
B. Obtain CXR
C. Obtain esophageal pH studies
D. Obtain spirometry
A
- B, Obtain CXR, p. 1038.
The next step in management is to obtain a chest x-ray. If the x-ray is normal, thenthis patient
represents the “clinical profile” of cough usually associated with UACS (upper airway cough
syndrome), asthma, NAEB (nonasthmatic eosinophilic bronchitis), or GERD. Once a normal xray is obtained, empiric therapy can be started based on the history.
28
Q
- In adults, which of the following details in the history has been shown to be
helpful indiagnosing the cause of a chronic cough?
A. Character of cough
B. Duration of cough
C. Sound quality of cough
D. Timing of cough
A
- B, Duration of cough, p. 1033.
In evaluating a patient with a cough, it is important to first obtain a detailed history.The
character of cough (productive, dry), sound quality (barking, honking), and timing
(nocturnal) have not been proven to help in diagnosis. Determining the duration of cough,
however, can help guide the differential. If the cough is determined to be chronic, UACS,
asthma, NAEB, and GERD have been proven to be the most likely causes.
29
Q
- Which of the following provides the correct diagnosis of chronic bronchitis?
A. Exposure to cigarette smoke only, dry cough, on most days over two years
B. Exposure to cigarette smoke only, productive cough, on most days during three
consecutive months for one year
C. Exposure to respiratory irritant, dry cough on most days over six consecutive monthsfortwo
consecutive years
D. Exposure to respiratory irritant, productive cough on most days during three consecutive
months for two consecutive years
A
- D, Exposure to respiratory irritant, productive cough on most days during three
consecutive months for two consecutive years, p. 1035.
Chronic bronchitis can be diagnosed in patients with exposure to respiratory irritants(dust,
fumes, smoke). Patients must expectorate phlegm on most days for three consecutive months
over two consecutive years. Other common causes of cough-phlegm syndrome (e.g., UACS,
bronchiectasis, asthma, GERD) must be ruled out and the cough must resolve after elimination
of irritant.
30
Q
6. Which of the following is responsible for the most cases of upper airway cough syndrome? A. Allergic rhinitis B. Bacterial sinusitis C. Fungal sinusitis D. Nonallergic rhinitis
A
- B, Bacterial sinusitis, p. 1035.
Of the causes listed, bacterial sinusitis accounts for the most cases of chronic cough (39% of
cases) due to UACS. The next most frequent is nonallergic rhinitis, followed by allergic rhinitis.
31
Q
7. What would be appropriate treatment of vasomotor rhinitis leading to upper airway cough syndrome? A. Budesonide nasal spray B. Ipratropium bromide nasal spray C. Loratadine D. Montelukast
A
- B, Ipratropium bromide nasal spray, p. 1037.
Vasomotor rhinitis is treated with ipratropium nasal spray. The other medicationscan be
used to treat allergic rhinitis.
32
Q
- Which of the following is characteristic of NAEB (nonasthmatic eosinophilic bronchitis)
only and not asthma?
A. Chronic cough can be the only presenting symptom
B. Mast cells present in airway mucosa but not in smooth muscle layer
C. Positive methacholine challenge test
D. Sputum eosinophilia
A
- B, Mast cells present in airway mucosa but not in smooth muscle layer, p. 1037.
In NAEB mast cells are present in the airway mucosa only. In asthma, mast cells are present
in the airway mucosa, submucosa, and smooth muscle layer. Methacholine challenge test
would be negative in NAEB but positive in Asthma. Chronic cough as the only symptom,
sputumeosinophilia, and a response to inhaled steroids can be seen in both asthma and
NAEB.