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 Table of Contents  
ORIGINAL ARTICLE
Year : 2014  |  Volume : 34  |  Issue : 1  |  Page : 46-52

Chronic idiopathic urticaria: autologous skin tests and treatment


1 Department of Dermatology and Venereology, Faculty of Medicine, Tanta University, Tanta, Egypt
2 Department of Clinical Pathology, Faculty of Medicine, Tanta University, Tanta, Egypt

Date of Submission17-Jan-2014
Date of Acceptance18-Mar-2014
Date of Web Publication24-Jul-2014

Correspondence Address:
Nahla R Ghaly
MD, Department of Dermatology & Venereology, Faculty of Medicine, Tanta University, 6111 Tanta
Egypt
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Source of Support: None, Conflict of Interest: None


DOI: 10.4103/1110-6530.137312

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  Abstract 

Background
Chronic urticaria is defined as urticaria persisting daily or almost daily for more than 6 weeks. It affects 0.1% of the population. Intradermal injection of autologous serum and plasma elicits a cutaneous reactivity in almost 45-60% of patients with chronic idiopathic urticaria (CIU). Activation of coagulation process seems to play an important role in the pathogenesis of CIU. Oral anticoagulant therapy has been shown to be effective in the treatment of CIU.
Objective
The aim of this study was to evaluate and compare autologous serum skin test (ASST) and autologous plasma skin test (APST) in the diagnosis of CIU and to determine the effect of treatment with antihistamine (loratadine) and anticoagulant (dipyridamole).
Patients and methods
This study included 30 patients suffering from CIU. All patients were subjected to intradermal testing with their serum (ASST) and their plasma (APST). The patients were classified into three equal groups, according to treatment: 10 patients were treated with loratidine, 10 patients were treated with dipyridamole, and 10 patients were treated with combination of loratidine and dipyridamole for 1 month. Follow-up for the three groups was carried out at the first, second, and fourth week of treatment evaluating the effectiveness and adverse effects of drugs. Assessment of the symptom score reduce index (SSRI) in positive and negative ASST and APST patients was evaluated.
Results
The ASST was positive in 40% of patients, whereas APST was positive in 90% of patients. Loratadine, dipyridamole, and combination of both were effective in the management of patients with CIU. However, best results occurred with combination of both. No serious side effects of treatment were encountered.
Conclusion
Both ASST and APST can be used for diagnostic purposes in patients with CIU. APST is superior to ASST in diagnosis of CIU. Combined treatment with antihistamines and anticoagulants provides an effective management of chronic urticaria in positive autologous serum and plasma skin tests patients.

Keywords: Anticoagulant, antihistamine, autologous plasma skin test, autologous serum skin test, urticaria


How to cite this article:
Dogheim NN, Gheida SF, Ghaly NR, Mahmoud Ibrahim AH, Abo El-Enein AM. Chronic idiopathic urticaria: autologous skin tests and treatment. Egypt J Dermatol Venerol 2014;34:46-52

How to cite this URL:
Dogheim NN, Gheida SF, Ghaly NR, Mahmoud Ibrahim AH, Abo El-Enein AM. Chronic idiopathic urticaria: autologous skin tests and treatment. Egypt J Dermatol Venerol [serial online] 2014 [cited 2023 Mar 31];34:46-52. Available from: http://www.ejdv.eg.net/text.asp?2014/34/1/46/137312


  Introduction Top


Chronic urticaria (CU) describes a 6-week or longer history of widespread, transient, itchy cutaneous swellings with or without angioedema, which affects 25% of the population at some time in their life [1]. Pathogenic mechanisms such as chronic infections, food intolerance, noninfectious chronic inflammatory processes (gastritis, oesophagitis) have been elucidated to be responsible for the development of CU. No apparent cause is identifiable in ∼70% of patients. The term chronic idiopathic urticaria (CIU) is used for defining CU patients in whom neither signs of vasculitis nor causative drugs, foods, and/or physical factors could be specified [2]. It has been identified from previous studies that CIU includes a heterogeneous subset (up to 46% of patients) that has a previously unidentified serum factor, which was discovered to be an antibody with an important role in the pathogenesis of CIU. Recently, an underlying autoimmune mechanism involving antihigh-affinity IgE receptor (FcåRI) antibodies or anti-IgE antibodies that are capable of activating mast cell and basophil degranulation was proposed [1]. In a subset of CU patients, intradermal injection of autologous serum elicits a wheal-and-flare skin reaction, which suggests the presence of a serum factor. The autologous serum skin test (ASST) is an in-vivo validated test performed by injecting the patient's own serum into the skin, which results positive in 30-67% of patients [2],[3]. ASST provides an easy, inexpensive investigation in CU and helps direct attention to underlying systemic autoimmune diseases. Although ASST is widely used and well established, there are concerns about the interpretation and specificity of this test. Some authors suggested that ASST might produce false-positive results because of the generation of large quantities of bradykinin during the clotting process and direct cleavage of C5 by tryptase such as plasma proteases secreted by neutrophils [1],[4]. Asero et al. [3] proposed using autologous plasma instead of autologous serum, which would be expected to result in a better accuracy of the test but cannot be considered as a screening test for histamine-releasing autoantibodies.

Antihistamines are widely used in treatment of CU as histamine is released from mast cells and basophils is claimed to play a crucial role in the pathogenesis of urticaria [1],[5]. The involvement of platelet-derived or clotting factors in the pathomechanism of CU is also suggested [2],[5]. Hence, anticoagulant drug (dipyridimol) can be effective in treatment of CU, with antihistamine (loratadine).

The aim of this study was to evaluate and compare ASST and autologous plasma skin test (APST) in the diagnosis of CIU and to determine the effect of treatment with antihistamine (loratadine) and anticoagulant (dipyridamole).


  Patients and methods Top


The present study was conducted on 30 patients recruited from the Outpatient Clinic of Dermatology, Tanta University Hospital (25 female patients and five male patients). Their age ranged from 19 to 63 years. The study and consent form were approved by the local ethical committee. All of them were diagnosed as CIU after exclusion of known causes by history, clinical examination, and investigations. All participants were subjected to complete history taking, thorough general and dermatologic examination, and routine laboratory investigations.

Patients with cholinergic urticaria, drug-induced urticaria, ultraviolet or physical urticaria, pregnant or lactating women, and patients with cardiac, hepatic, or renal diseases were excluded. Patients with underlying cause such as infection, internal disease, thyroid disease, gastric troubles (Helicobacter pylori), parasites, collagen disease, or vasculitis were also excluded. All patients ceased any systemic treatment 1 month before the enrollment in the study. All patients were subjected to the following investigations.

Routine laboratory investigation

All patients underwent urine and stool analysis, complete blood cell count with differential count of neutrophil, eosinophil, and basophil, ESR, bleeding and coagulation surveys, antinuclear antibodies, liver function tests, kidney function tests, thyroid function tests, and hepatitis B and C titers.

Intradermal skin tests

Two venous blood samples (2 ml each) were obtained from each patient. For serum, the first 2 ml of patient's blood was collected in a sterile glass tube and was allowed to clot for 30 min at room temperature. For plasma, the second blood sample was collected in citrate anticoagulant in a sterile glass tube (0.125 mol/l of sodium citrate). The serum and plasma were separated by centrifugation at 500g for 15 min and were used immediately to minimize any risk of sample contamination or labeling errors. The injection was given with a 0.5-1 ml insulin sterile syringe without dead space using 0.05 ml of fresh undiluted serum and plasma of the same patient and 0.9% sterile saline as a negative control. Superficial intradermal injection should be made by introducing the bevel of the needle uppermost and aiming to raise a palpable bleb of fluid within the papillary dermis. The site of injection was the volar forearm skin after cleansing with antiseptic, avoiding the wrist and skin known to have spontaneous wheals in the previous 48 h [to avoid sites where mast cells may be refractory to further activation (local tachyphylaxis)], leaving 3-5 cm gaps between each of the three injections (serum, plasma, and saline) and from the wrists and elbows.

Test reading

Intradermal tests (serum, plasma, and saline) readings were taken at 30 min. Test was considered positive if the wheal of ASST or APST was at least 3 mm more than those of negative control with saline.

Treatment regimen

The patients were classified into three equal groups:

Group I: Ten patients were treated with loratadine (10 mg once daily).

Group II: Ten patients were treated with dipyridamol (25 mg three times daily).

Group III: Ten patients were treated with combination of both loratadine and dipyridamol (mentioned dose and duration).

Follow-up for the three groups was carried out at the first, second, and fourth week of treatment, evaluating the effectiveness and adverse effects of drugs. Patient's symptoms and signs were recorded according to four levels as shown in [Table 1] [6]. Meanwhile, patient's assessment before and after 1 month of treatment was performed according to an integral signs and symptom score [6].
Table 1: Chronic urticaria signs and symptoms score [6]

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The validity of treatment efficacy according to SSRI was evaluated as invalid when SSRI < 0.20, effective when 0.60 > SSRI ≥ 0.20, obvious effective when 0.90 > SSRI ≥ 0.60, and clinical cure when SSRI ≥ 0.90.

The rate of effectiveness is the combined number of patients with clinical cure and obvious effect divided by total number of patients [6]. Assessment of SSRI in positive and negative ASST and APST patients was evaluated.

Statistical analysis

The analysis was performed using SPSS for windows statistics software package (SPSS Inc., 233 South Wacker Drive, Chicago, IL, USA). Data were expressed as mean±SD. P-values less than 0.05 were considered significant. Parametric tests such as t-test were applied for data that followed normal distribution. Nonparametric tests such as the Mann-Whitney U-test and the χ2 -test were applied for data that did not follow normal distribution.


  Results Top


Baseline data

This study included 30 patients suffering from CIU, 25 female patients (83.3%) and five male patients (16.7%). Their ages ranged from 19 to 63 years with a mean of 34.66 (±10.48) years. Duration of the disease varied from 4 to 86 months with a mean of 17.33 (±3.62) months. Family history was negative for all patients. There was no significant difference in the baseline data between the three groups, including age, sex, disease duration, and symptom score (P > 0.05).

Intradermal skin tests results

ASST was positive in 12 of 30 patients (40%) and APST was positive in 27 of 30 patients (90%). The APST was positive in 10 of 12 (83.3%) ASST-positive patients, and negative in two of 12 (16.7%) ASST-positive patients. The APST was positive in 17 of 18 (94.4%) ASST-negative patients, and negative in one of 18 (5.6%) ASST-negative patients. There was no significant difference between ASST and APST (P = 0.358). Cross-tabulation of the results in the total and treatment groups is illustrated in [Table 3] [Table 2] and [Figure 1],[Figure 2],[Figure 3] and [Figure 4]. ASST was positive in 20, 30, and 70% of patients in group I, II, and III, respectively. The difference between the three groups was statistically significant (P = 0.047; [Table 3]). APST was positive in 80, 20, and 90% of patients in group I, II, and III, respectively. The difference between the three groups was statistically insignificant (P = 0.325; [Table 4]).
Figure 1:

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Figure 2:

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Figure 3:

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Figure 4:

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Table 2: Relationship between ASST and APST in chronic idiopathic urticaria patients

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Table 3: Percentage of positivity and negativity of ASST in the patient groups

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Table 4: Percentage of positivity and negativity of APST in the patient groups

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Treatment results

The symptom scores significantly improved in all groups (P < 0.05). The mean symptom score reduce index (SSRI) was 0.60 (±0.18), 0.68 (±0.10), and 0.88 (±0.06) in groups I, II, and III, respectively. The difference in SSRI between the three groups was statistically significant, where group III showed higher SSRI improvement (P = 0.001). The difference in SSRI between group I and II, group I and III, and group II and III was statistically significant (P = 0.014, 0.001, and 0.002, respectively; [Table 5] and [Figure 5]. SSRI showed no statistically significant correlation with age (P = 0.303), sex (P = 0.744), family history (P = 0.999), and duration of the disease (P = 0.985).
Figure 5:

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Table 5: Symptom score reduce index in the patient groups

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With respect to the validity of clinical treatment effect according to SSRI in group I, it was effective in 75%, obvious effective in 21.4%, and clinical cure in 12.5% of patients. The rate of effectiveness was 40%. In group II, it was effective in 25%, obvious effective in 57.1%, and clinical cure in 0% of the patients. The rate of effectiveness was 80%. In group III, it was obvious effective in 21.4% and clinical cure in 87.5% of patients. The rate of effectivity was 100% [Table 6]. Group III showed significant efficacy of treatment when compared with the other two groups (P < 0.01).
Table 6: The validity of clinical treatment effect according to symptoms score reduce index in the patient groups

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In ASST-positive patients, there was clinical cure in five patients (four in group III and one in group I) and the obvious effective patients were six in number (three in group III, two in group II, and one in group I). The rate of effectiveness was 100% in group I, 66.6% in group II, and 100% in group III. In contrast, in APST-positive patients, there was clinical cure in seven patients (all in group III) and the obvious effected patients were 15 in number (three in group III, seven in group II, and five in group I). The rate of effectiveness was 62.5% in group I, 77.7% in group II, and 100% in group III.

Side effects of treatment

The main adverse reactions in patients were mild drowsiness, headache, and dizziness in one patient of group I; headache in one patient of group II; and dry mouth and gastrointestinal discomfort in one patient of group III. Adverse reactions were tolerable and did not interfere with daily activities. No serious side effects were encountered.


  Discussion Top


CU is a common skin disorder characterized by recurrent eruption of short-lived wheals accompanied by redness and itching on most days of the week for at least 6 weeks [7]. CU is associated with severely impaired quality of life and CU patients frequently suffer from depression and anxiety. ASST is the simplest and the best in-vivo clinical test for detection of basophil histamine-releasing activity. ASST is simple, semi-invasive, inexpensive, and easy to perform. Results can be obtained within 30 min. APST is claimed to be a more sensitive and reliable in-vivo skin test than ASST [3].

In this study, ASST was positive in 40% of patients and negative in 60% of patients, whereas APST was positive in 90% of patients and negative in 10% of patients. APST was positive in 83.3% of ASST-positive patients and negative in 16.7% of ASST-positive patients. APST was positive in 94.4% of ASST-negative patients and negative in 5.6% of ASST-negative patients. These findings are in agreement with those of Asero et al. [3] who showed that 53% of CIU patients scored positive on ASST and 86% of patients scored positive on APST. APST was positive in 70% of ASST-negative patients and in 98% of ASST-positive patients. Sajedi et al. [8] reported that APST is a sensitive method for detection of functional autoantibodies in patients with CIU, as ASST was positive in 65.5% and APST was positive in 77.6% of their patients. Thirty-seven patients were positive for both ASST and APST and 12 patients were negative for both skin tests. One patient was negative for APST and positive for ASST, whereas 18 patients were APST positive and ASST negative. They concluded that there is agreement of ASST and APST in 84% of patients for negative or positive results. It is suggested to check both tests simultaneously to confirm the result of either test. Previous studies have evaluated the accuracy of ASST to be 30-67% of patients [2],[3]. Caproni et al. [9] mentioned that ASST alone is not sufficient to define CIU as an autoimmune disease. However, ASST has often been chosen as an experimental model because it has an effect very similar to that of the physiological stimulus that induces wheal in urticaria.

It has been reported that the intradermal injection of autologous serum in some patients with CIU produces a wheal-and-flare response. The simple observation suggested that there were circulating histamine-releasing factors in urticaria patients, and this led to the identification of functional anti-FcεRI autoantibodies in CIU. A positive ASST may indicate the presence of functional anti-IgE autoantibodies and other histamine-releasing factors [7]. ASST gives an approximate idea about basophil and mast cell histamine-releasing propensity of a patient with CIU; hence, positive ASST is suggestive but not diagnostic of an autoimmune basis for CIU. In contrast, it has been suggested that ASST might produce false-positive results because of the generation of large quantities of bradykinin during the clotting process and direct cleavage of C5 by tryptase such as plasma proteases secreted by neutrophils [10].

Asero et al. [3] recommended using APST instead of ASST. They reported that APST was positive in 97 and 87% of urticaria patients in two different studies [3],[11]. In the present study, APST was positive in 90% of our patients. The striking difference between ASST and APST results pointed to a possible role by platelet-derived or clotting factors in the skin reaction. The extrinsic pathway of the coagulation cascade is activated in CIU, thus it is predictable that APST generates more positive responses than ASST because plasma contains coagulation factors and complements. Therefore, consumption of coagulation factors and formation of clot seem to be responsible for less positive results with ASST [8]. In contrast, Kocaturk et al. [10] reported that ASST was superior to APST and had the ability to detect more patients with autoreactive urticaria than APST. They concluded that there is no need to use autologous plasma instead of autologous serum for intradermal testing in CU. Other authors have explained that the high rate of positivity of APST is due to the difference between the individuals performing the test, the absence of standardized methods for assessment, variation in patient selection, and differences in presentation of the results [8],[12].

In the present study, the symptom scores showed significant improvement in all groups of patients. The SSRI and the validity of efficacy of treatment showed significant improvement in group III when compared with the other two groups. The rate of effectiveness was 100% in group III. As dipyridamol inhibits phosphodiesterase, this causes a relative increase in the concentration of intracellular cyclic adenosine monophosphate, thereby suppressing the degranulation of mast cells or basophils. In addition, dipyridamol can inhibit platelet aggregation, platelet membrane, and adenosine diphosphate, and high concentrations of dipyridamol inhibit collagen, thrombin, and epinephrine-induced platelet release reaction [13],[14],[15],[16]. Xiaoming et al. [6] showed that the levels of plasma prothrombin F1+2 in autoimmunity (CU) patients have decreased obviously after treatment with dipyridamol. Before treatment, the levels of the treatment group were higher than that of the control group. After treatment, they had no significant difference.

Pathogenesis of CIU involves the activation of the coagulation cascade, which results in thrombin production. Thrombin is a serine protease that may play a key role in urticaria by inducing edema through an increase in vascular permeability, mast cell activation and degranulation, and production of the anaphylatoxin C5a. Such mechanism seems to be active in the majority of CIU patients; however, their relationship with anti-FcåRI or anti-IgE autoantibodies is still a matter of research [17]. Irrespective of the mechanism of coagulation activation (primary or secondary), the presence of thrombin, an enzyme that increases permeability of blood vessels, seems to play an important role in the pathogenesis of CIU, suggesting the efficacy of heparin in treatment of CIU. In fact, both heparin (which increases the antithrombin activity highly in plasma) and oral anticoagulant therapy (which reduces thrombin generation in vivo) have been shown to be effective in the treatment of CIU [11]. Significance of blood platelets in urticarial inflammatory process is poorly recognized but poorly characterized in urticaria. It is known that platelets are activated during the inflammatory processes and are involved in modulating inflammatory and immune response by various mediator releases. Platelets have been described as a source of inflammatory mediators that are implicated in histamine release from basophils and mast cells [14],[18]. Moreover, it has been shown that histamine is released by human platelets in response to aggregator and immunological stimuli. In turn, exogenous histamine potentiates platelet activity measured by the aggregation induced by different agonists, acting through histamine receptors [19].

The side effects of treatment in the current study were in few patients and were relatively minor and not affecting daily life; some showed mild drowsiness, headache, dizziness, dry mouth, and gastrointestinal discomfort, explaining why Xiomang et al. [6] found similar adverse effects on using dipyridimol in treatment of CU.

A point of interest in this study was that, after ASST and APST, the patients showed a significant improvement in their signs and symptoms. Either they experienced mild diseases or no relapse for at least 1 month after the tests, indicating that ASST and APST could be an alternative therapy.


  Conclusion Top


Both APST and ASST can be used for diagnostic purposes in patients with CIU. APST is superior to ASST in the diagnosis of CIU. Combined treatment with antihistamines and anticoagulants provides an effective management of CU, especially in ASST and APST-positive patients. Further studies with large number of patients and long-term follow-up are warranted checking the possibility of using ASST and APST as new therapeutic modalities in the treatment of CIU.


  Acknowledgements Top


Conflicts of interest

None declared.

 
  References Top

1.Kaplan AP, Greaves M. Pathogenesis of chronic urticaria. Clin Exp Allergy 2009; 39 :777-787.  Back to cited text no. 1
    
2. Sabroe RA, Grattan CE, Francis DM, Barr RM, Kobza Black A, Greaves MW. The autologous serum skin test: a screening test for autoantibodies in chronic idiopathic urticaria. Br J Dermatol 1999; 140 :446-452.  Back to cited text no. 2
    
3. Asero R, Tedeschi A, Riboldi P, Cugno M. Plasma of patients with chronic urticaria shows signs of thrombin generation, and its intradermal injection causes wheal-and-flare reactions much more frequently than autologous serum. J Allergy Clin Immunol 2006; 117 :1113-1117.  Back to cited text no. 3
    
4. Kaplan AP. Biologic agents in the treatment of urticaria. Curr Allergy Asthma Rep 2012; 12 :288-291.  Back to cited text no. 4
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5. Kaplan AP. Chronic urticaria: pathogenesis and treatment. J Allergy Clin Immunol 2004; 114 :465-474; quiz 475  Back to cited text no. 5
    
6. Xiaoming L, Wanxiang S, Khalaf A, Jiquan S, Jinquan T. Relation between autoimmunity chronic urticaria and the levels of plasma prothrombin F1+2. Am J Appl Sci 2007; 4 :965-969.  Back to cited text no. 6
    
7. Sabroe RA, Seed PT, Francis DM, Barr RM, Black AK, Greaves MW. Chronic idiopathic urticaria: comparison of the clinical features of patients with and without anti-FcepsilonRI or anti-IgE autoantibodies. J Am Acad Dermatol 1999; 40 :443-450.  Back to cited text no. 7
    
8. Sajedi V, Movahedi M, Aghamohammadi A, Gharagozlou M, Shafiei A, Soheili H, Sanajian N, et al. Comparison between sensitivity of autologous skin serum test and autologous plasma skin test in patients with chronic idiopathic urticaria for detection of antibody against IgE or IgE receptor (FcepsilonRIalpha). Iran J Allergy Asthma Immunol 2011; 10 :111-117.  Back to cited text no. 8
    
9. Caproni M, Volpi W, Macchia D, et al. Infiltrating cells and related cytokines in lesional skin of patients with chronic idiopathic urticaria and positive autologous serum skin test. Exp Dermatol 2003; 12 :621-628.  Back to cited text no. 9
    
10.1Kocaturk E, Kavala M, Kural E, Sarigul S, Zindanci I. Autologous serum skin test vs autologous plasma skin test in patients with chronic urticaria: evaluation of reproducibility, sensitivity and specificity and relationship with disease activity, quality of life and anti-thyroid antibodies. Eur J Dermatol 2011; 21 :339-343.  Back to cited text no. 10
    
11.1Asero R, Tedeschi A, Coppola R, et al. Activation of the tissue factor pathway of blood coagulation in patients with chronic urticaria. J Allergy Clin Immunol 2007; 119 :705-710.  Back to cited text no. 11
    
12.1Godse KV. Autologous serum skin test v/s autologous plasma skin test. Indian J Dermatol Venereol Leprol 2008; 74 :496-497.  Back to cited text no. 12
    
13.1Zhu H, Liang B, Li R, et al. Activation of coagulation, anti-coagulation, fibrinolysis and the complement system in patients with urticaria. Asian Pac J Allergy Immunol 2013; 31 :43-50.  Back to cited text no. 13
    
14.1Asero R, Tedeschi A. Emerging drugs for chronic urticaria. Expert Opin Emerg Drugs 2006; 11 :265-274.  Back to cited text no. 14
    
15.1Asero R, Tedeschi A, Cugno M. Treatment of refractory chronic urticaria: current and future therapeutic options. Am J Clin Dermatol 2013; 14 :481-488.  Back to cited text no. 15
    
16.1Asero R, Tedeschi A, Cugno M. Treatment of chronic urticaria. Immunol Allergy Clin North Am 2014; 34 :105-116.  Back to cited text no. 16
    
17.1Goh CL, Tan KT. Chronic autoimmune urticaria: where we stand? Indian J Dermatol 2009; 54 :269-274.  Back to cited text no. 17
    
18.1Suzuki R, Kimura T, Kitaichi K, et al. Platelet factor 4 fragment induces histamine release from rat peritoneal mast cells. Peptides 2002; 23 :1713-1717.  Back to cited text no. 18
    
19.1Masini E, Di Bello MG, Raspanti S, et al. The role of histamine in platelet aggregation by physiological and immunological stimuli. Inflamm Res 1998; 47 :211-220.  Back to cited text no. 19
    


    Figures

  [Figure 1], [Figure 2], [Figure 3], [Figure 4], [Figure 5]
 
 
    Tables

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