Superficial Cryotherapy versus Intralesional Corticosteroids Injection in Alopecia Areata: A Trichoscopic Comparative Study.

Background: Alopecia areata (AA) is an autoimmune disease leading to noncicatricial alopecia. Topical or intralesional corticosteroid (ILCS) is the accepted therapeutic option for mild cases; however, adverse effects are sometimes difficult to reverse. When the exposure to liquefied nitrogen is limited to a few seconds "superficial" cryotherapy, reactive vasodilation may improve microcirculation and nutritional status around hair follicles. Objective: This study aimed to evaluate and compare superficial cryotherapy and ILCS in the treatment of patchy AA. Materials and
Methods: This prospective comparative study included 21 patients with patchy AA. Every patient received superficial cryotherapy on one patch, every 2 weeks for 3 months, and ILCS injection for another patch, once monthly for 3 months.
Results: Clinical improvement was higher in cryotherapy group compared to ILCS group with a statistically significant difference (P = 0.002). On trichoscopic evaluation, terminal hair count was improved in lesions treated with cryotherapy more than lesions treated with ILCS but without statistical significance (P = 0.595) and vellus hair count was improved in lesions treated with cryotherapy more than lesions treated with ILCS with a statistical significance (P = 0.002). Conclusions: Cryotherapy is more effective and less painful than ILCS in the treatment of patchy AA. Copyright:

INTRODUCTION

Alopecia areata (AA) is an autoimmune disease of the hair follicles leading to noncicatricial alopecia. It is usually associated with other autoimmune diseases, such as atopy and autoimmune thyroiditis. About 1%–2% is the estimated lifetime prevalence of AA.[1]

Topical or intralesional corticosteroid (ILCS) is the preferred therapeutic option for mild AA patients. However, possible adverse effects of potent corticosteroids, such as telangiectasia and skin atrophy, are sometimes difficult to reverse, and ILCS injection might not be suitable when dealing with young patients due to its painful nature.[2] Anaphylaxis in patients receiving ILCS for treatment of AA has been reported in some cases.[3]

Cryotherapy was introduced for the first time as a treatment of AA in 1986. “Superficial” cryotherapy where the exposure to liquefied nitrogen is limited to a few seconds results in reactive vasodilation and increase in blood flow that may improve microcirculation and nutritional status around hair follicles.[45]

Superficial cryotherapy has a conflicting mechanism with the traditional AA treatments. It could be a meaningful adjuvant treatment option for AA patients especially in mild cases, or when the conventional AA treatment is not applicable considering that it is less painful and easier to perform.[6]

Our aim was to evaluate and compare the efficacy and safety of superficial cryotherapy and ILCS in the treatment of patchy AA as well as reporting the side effects.

MATERIALS AND METHODS

This prospective comparative study included 21 patients with patchy AA (at least 2 patches). Only one case was excluded and discontinued at the 9th week of treatment for the development of atrophy and telangiectasia after ILCS

The study was approved by the Research Ethical Committee. All patients received full information about the procedure, possible side effects, photo documentation, and they all provided written informed consent

Pregnant and lactating females, patients suffering from concomitant inflammatory, infectious or autoimmune cutaneous or systemic disease, patients with co-existent medical condition of the scalp, previous topical treatment in the last 1 month or systemic treatment in the last 3 month for AA, patients with alopecia totalis or alopecia universalis, patients with any contraindication for cryotherapy such as agammaglobulinemia, cold uritcaria, cryoglobulinemia, pyoderma gangrenosum, raynaud disease, blistering disorders, and usage of any anticoagulants, and patients with any contraindication for ILCS such as active skin infection at the site of injection or known triamcinolone allergy were excluded

All patients were subjected to the following: Detailed history taking, complete general examination, local scalp examination to assess sites, number, and size of AA patches, digital photography using Honor android 8 × 16.1 Megapixels® digital Camera (Shanghai, China) for each patient at the start of treatment, as well as 1 month after the last treatment session and trichoscopic examination using DermLite Dl4® dermoscope (USA) to confirm diagnosis of AA and for assessment of the response to treatment from a fixed site in the scalp recorded in the medical record

Every patient was assigned to receive superficial cryotherapy on one patch of AA, every 2 weeks for 3 months duration (7 sessions). Superficial cryotherapy was performed by spraying liquid nitrogen 3–4 times for 2–3 s per application, using Cryopro® (Cortex Technology, Hadsund, Denmark). ILCS injection was done for another patch of AA, once monthly for 3 months (4 sessions) (triamcinolone acetonide, 5 mg/ml, 1 ml injected). A topical anesthetic cream (pridocaine cream) was applied 30 min before the procedure

Evaluation of results: It was done 1 month after the last treatment session by clinical assessment through comparing patients' digital photographs and clinical response was defined as hair re-growth in the manner of poor response (0%–20% re-growth), mild response (20%–50% re-growth), moderate (50%–75% re-growth), and excellent response (>75% re-growth),[7] the trichoscopic images taken before and 1 month after the last treatment session were then analyzed using special software (Trichosan®) to identify and compare the number and density of total terminal/vellus hairs (VHs) per unit area (70 mm2 circular area) and also to compare other occasional signs of AA like black dots (BDs), yellow dots (YDs), and exclamation mark hairs (EMHs), also assessment for side effects of therapy was done

Data management and analysis: The collected data were revised, coded, tabulated, and introduced to a PC using Statistical Package for Social (SPSS 15.0.1; SPSS Inc., 2001, Chicago, USA). The quantitative data were presented as mean and standard deviations. Also, qualitative variables were presented as frequency and percentages. Paired t-test was used to assess the statistical significance of the difference between two means measured twice for the same study group. Correlation analysis was used for the detection of correlation between two quantitative variables. The correlation coefficient denoted symbolically “r” defines the strength and direction of the linear relationship between two variables. Statistical significance: P > 0.05: Nonsignificant, P ≤ 0.05: Significant (S), and P ≤ 0.01: Highly significant.

RESULTS

Included patients in this study were 6 males (30%) and 14 females (70%). The mean age was 25 ± 11.211 years with a minimum age of 10 years and maximum of 42 years old. The mean duration of the current AA lesions was 2.85 ± 2.159 months with a minimum duration of 1 month and maximum of 8 months.

On evaluation of clinical improvement at the end of treatment course (week 16), in cryotherapy group, two lesions (10%) showed an excellent response [Figure 1], three lesions (15%) showed moderate response, 11 lesions (55%) showed a mild response, and four lesions (20%) showed a poor response. While in the ILCS group, ten lesions (50%) showed a poor response [Figure 2] and the other ten (50%) showed mild response. Clinical improvement at the end of treatment was higher in cryotherapy treatment group compared to ILCS treatment group with a high statistically significant difference (P = 0.002).

Figure 1

15-year-old male with alopecia areata of 4-month duration. (a1) Digital image before cryotherapy sessions. (a2) Digital image after cryotherapy treatment (week 16). (b1) Trichoscopic image before cryotherapy: Terminal hair: 26 vellus hair: 40 black dots: 7 yellow dots: 45 EM: 0. (b2) Trichoscopic image after cryotherapy (week 16): Terminal hair: 91 vellus hair: 68 black dots: 0 yellow dots: 13 EM: 0. Yellow marks: Yellow dots, Purple marks: Terminal hair, Light blue marks: Vellus hair, Blue marks: Black dots, Green marks: Exclamation mark hairs

Figure 2

15-year-old male with alopecia areata of 4-month duration. (a1) Digital image before intralesional corticosteroid sessions. (a2) Digital image after intralesional corticosteroid treatment (week 16). (b1) Trichoscopic image before intralesional corticosteroid: Terminal hair: 42 vellus hair: 19 black dots: 11 yellow dots: 6 EM: 3. (b2) Trichoscopic image after intralesional corticosteroid (week 16): Terminal hair: 85 vellus hair: 23 black dots: 24 yellow dots: 6 EM: 0. Yellow marks: Yellow dots, Purple marks: Terminal hair, Light blue marks: Vellus hair, Blue marks: Black dots, Green marks: Exclamation mark hairs

On trichoscopic evaluation of response to cryotherapy in comparison to ILCS, terminal hair (TH) count was higher after cryotherapy treatment compared to before treatment but without statistically significant difference (P = 0.176). Also, TH count was higher after ILCS treatment compared to before treatment but without statistically significant difference (P = 0.416). TH count was improved in lesions treated with cryotherapy more than lesions treated with ILCS but without statistically significant difference (P = 0.595) [Table 1].

Table 1

Terminal hair count response to treatment

Terminal hair (hair/cm2)	Groups		T-test
	Cryotherapy	ILCS	T	P
Before treatment
Range	6-103	18-85
Mean±SD	41.000±26.436	40.700±19.326
After treatment
Range	11-91	22-86
Mean±SD	47.700±19.151	44.050±16.816
Differences
Mean±SD	−6.700±21.320	−3.350±18.024	−0.537	0.595
Paired test (P)	0.176	0.416

Paired t-test. SD – Standard deviation, ILCS – Intralesional corticosteroids

VH count was significantly higher after cryotherapy treatment compared to before treatment (P = 0.001). Also, VH count was higher after ILCS treatment compared to before treatment but without statistically significant difference (P = 0.344). VH count was improved in lesions treated with cryotherapy more than lesions treated with ILCS with a high statistically significant difference (P = 0.002) [Table 2].

Table 2

Vellus hair count response to treatment

Vellus hair (hair/cm2)	Groups		T-test
	Cryotherapy	ILCS	T	P
Before treatment
Range	46-93	10-66
Mean±SD	70.450±14.177	38.200±13.679
After treatment
Range	52-127	14-94
Mean±SD	92.000±18.290	41.200±18.797
Differences
Mean±SD	−21.550±20.433	−3.000±13.815	−3.363	0.002*
Paired test (P)	0.001*	0.344

Paired t-test. SD – Standard deviation, ILCS – Intralesional corticosteroids, *Highly significant

BDs count was lower after cryotherapy treatment compared to before treatment with a statistically significant difference (P = 0.026). Also, BDs were lower after ILCS treatment compared to before treatment but without a statistically significant difference (P = 0.308). The decrease in the number of BDs in lesions treated with cryotherapy was more than lesions treated with ILCS but without a statistically significant difference (P = 0.153).

YD count was lower after cryotherapy treatment compared to before treatment with a statistically significant difference (P = 0.037). Also, YD count was lower after ILCS treatment compared to before treatment but without a statistically significant difference (P = 0.172). The decrease in the number of YDs in lesions treated with cryotherapy was more than lesions treated with ILCS but without a statistically significant difference (P = 0.497).

EMH count was lower after cryotherapy treatment compared to before treatment with a statistically significant difference (P = 0.017). Also, EMH count was lower after ILCS treatment compared to before treatment but without a statistically significant difference (P = 0.066). The decrease in the number of EMs in lesions treated with cryotherapy was more than lesions treated with ILCS but without a statistically significant difference (P = 0.874).

By studying the clinical response to cryotherapy in relation to the age of the patients, we found that 41.17% of the lesions that responded to cryotherapy were in patients aged more than 25 years compared with 58.8% of lesions in patients aged <25 years, but the difference was not statistically significant (P = 0.973). In comparison, the clinical response to ILCS in relation to the age of the patients, we found that 30% of the lesions that responded to ILCS were in the age group above 25 years, while it was 70% in the age group <25 years, but the difference was not statistically significant (P = 0.603) [Table 3].

Table 3

Correlation between clinical response to treatment in relation to the age of onset and duration of alopecia areata

	Age		Duration
	r	P	r	P
Clinical improvement after cryotherapy	−0.008	0.973	0.002	0.993
Clinical improvement after ILCS	−0.124	0.603	−0.263	0.262

P≤0.05 is significant using paired t-test. r – Nonsignificant using linear correlation coefficient; ILCS – Intralesional corticosteroids

Regarding the clinical response to cryotherapy in relation to the duration of onset of AA, it was found that 84.21% of the lesions responded to the treatment when the disease duration was <6 months, but the difference was not statistically significant (P = 0.993), while the clinical response to ILCS in relation to the duration of the disease showed that 52.63% of the lesions responded better when the duration was below 6 months, but the difference was not statistically significant (P = 0.262) [Table 3].

There were no side effects reported as regards superficial cryotherapy sessions, while after ILCS sessions, five cases reported severe pain during session, burning sensation after injection, and headache. Atrophy and telangiectasia were only reported in one case that discontinued at 9th week of treatment.

DISCUSSION

AA presentation had a great variation in the time of initial onset, the duration, extent, and pattern of hair loss during any episode of active loss. Moreover, the course of disease is unpredictable, spontaneous re-growth of hair occurs in many patients within the 1st year, and sudden relapse may occur at any time.[8] Thus, diagnosis and management may be difficult and challenging due to the clinical variability and unpredictable nature of spontaneous re-growth.

Trichoscopy is used increasingly for the evaluation of hair loss either scarring or nonscarring. Trichoscopy is not only helpful in the diagnosis of different hair disorders but also helpful in the assessment of treatment response, especially in androgenetic alopecia. However, there are no evidence-based data on how to predict or assess response to therapy in patients with AA apart from AA prediction score (AAPS) introduced by Waśkiel-Burnat et al. in 2019.[9]

AAPS can be used in patients with patchy AA to predict the possibility of hair regrowth. Most of the used methods for assessment of treatment response in AA are subjective; in our work, we choose to use trichoscopy for a better objective assessment.

A fixed point was chosen at the margins of AA patch and photographed before and after treatment to compare TH count, VH count, BDs, YDs, and EMH. This allows objective assessment of treatment response and also comparing the degree of improvement between different treatment modalities.

According to the treatment guideline suggested by Alkhalifah et al. in 2010 and Messenger et al. in 2012, topical or ILCS is the accepted therapeutic option for mild AA patients,[210] However, possible adverse effects of potent corticosteroids are sometimes difficult to reverse, and ILCS injection might not be suitable due to its painful nature when dealing with young AA patients.

Since introduced by Huang et al. in 1986, the therapeutic efficacy of superficial cryotherapy in AA has been studied by various studies.[45111213] It is on this basis that we performed this study on patients with patchy AA to evaluate the efficacy of superficial cryotherapy and to compare it to the most commonly used treatment of AA (ILCS) and this to the best of our knowledge is the second study to compare both modalities.

In our study, the overall clinical response of AA lesions treated with cryotherapy was 80% (hair re-growth >20%) and that was a little bit better than the results of Kim et al. in 1994 that showed that superficial cryotherapy induced TH regrowth in 66.7% of patients.[13] Similarly, Hong et al. in 2006 in their Korean study done on 153 patients with AA, 68.6% of patients showed a therapeutic response after 12 weeks of treatment with superficial cryotherapy.[14] In Jun et al., 60.9% of the patients were considered as responders to cryotherapy.[15] Also in Abdel-Majid et al. in 2018, the overall clinical response of AA lesions treated with cryotherapy was 65%.[7]

Another study using a different cryotherapy technique was done in 2013 by Radmanesh and Azar-Beig on 44 patients with AA or alopecia totalis treated with a closed contact CO2 system for 8 weeks. They suggest that the immunologic process and structural components of the hair follicle responsible for AA may be altered by cold-induced inflammation. Their study showed a positive therapeutic response in 65.9% of patients.[16]

However, our results were a little bit lower than that of Lei et al. in 1991 who tried cryotherapy on patients with AA once weekly for 4 weeks, 97.2% improvement was observed compared with 80% in our study.[5] This could be explained by a large number of the studied patients (119 AA patients) and the different cryotherapy technique (a cotton swab technique). According to Lee et al., clinical improvement of AA by superficial cryotherapy could be through blocking a yet unrevealed pathophysiologic process associated with abnormal melanocytes with large and bizarre melanosomes, found around the hair follicles of AA patients.[11]

Owing to its minimally painful and nondestructive nature, superficial cryotherapy has proven its efficacy in treatment of AA in fragile areas, such as the eyebrow.[1718]

Although ILCS is used frequently in the treatment of AA, few clinical trials are available in the literature on its use in AA. Porter and Burton in 1971 showed that hair re-growth was observed in 64% of AA sites treated by intralesional injections of triamcinolone acetonide.[19] In addition Kubeyinje in 1994, 63% of patients receiving monthly triamcinolone injections showed complete re-growth in an uncontrolled study from Saudi Arabia.[20]

While Alkhalifah et al. in 2010 observed hair re-growth in71% of patients with AA treated by ILCS injections 3 times every 2 weeks and in 7% of control subjects injected with isotonic saline,[10] Ranawaka in 2014, a cohort study of 290 patients of AA, showed improvement in 61% of patients after 1-2 ILCS injections.[21] However, our results regarding the clinical response to ILCS treatment were a little bit lower than all the previously mentioned studies, only 50% of lesions showed a response (>20% hair regrowth).

Immunosuppression is the main mechanism of action of ILCS. The T-cell-mediated immune attack on the hair follicle can be suppressed by corticosteroids. Preparations used include triamcinolone hexacetonide, triamcinolone acetonide, and hydrocortisone acetate. Triamcinolone acetonide is the preferred intralesional product because it is less atrophogenic than triamcinolone hexacetonide.[2223]

Our results agree with Gita and Mohammadreza, who compared the efficacy between cryotherapy and topical 0.1% betamethasone in treatment of AA in 40 patients with AA and found that the overall response rate of patches was 91.5% in the cryotherapy group and 80% in the clobetasol group. However, Gita and Mohammadreza in 2013 compared cryotherapy to topical not ILCS and this affects their results in comparison to ours due to poor absorption of topical steroids compared to intralesional injection.[12]

However, our results disagree with Amirnia et al. in 2015, 83.3% of patients treated with ILCS showed a good response compared to patients treated with superficial cryotherapy who showed a response in only 56.7%. This could be due to variation in the strategy of treatment as in their work they divided their patients into two groups, one group was treated with cryotherapy, while the other group was treated with ILCS injection; in our work, we compared both modalities in the same patients and this excludes some factors that may influence the results such as age, sex and individual variations in the response to treatment and this adds to the power of the present work. Also in Amirnia et al. in 2015, ILCS injection was done every 2 weeks, but in our work, we choose to do ILCS injection every 1 month to decrease the incidence of side effects as atrophy and telangiectasia.[24]

As regards the trichoscopic findings, TH count and VH count were improved in lesions treated with cryotherapy more than lesions treated with ILCS. There was a decrease in the number of BDs, YDs, and EMHs seen in lesions treated with cryotherapy more than lesions treated with ILCS.

Similarly Jun et al. in 2017, who also demonstrated the efficacy of superficial cryotherapy as an adjuvant therapeutic option, combined with topical steroids, 73.3% experienced improvement in disease indicated by re-growth of TH which was calculated using phototrichogram analysis and that was the only study found in the literature using phototrichogram in the assessment of response to treatment in AA.[6]

Despite these hypotheses, there is currently no established theory of how superficial cryotherapy works in the treatment of AA. However, its therapeutic efficacy has been proven in various previous studies.

Our conclusion is that both cryotherapy and ILCS injection are safe and effective modalities in the treatment of patchy AA with cryotherapy being more effective and at the same time less painful than ILCS injection, thus cryotherapy is better to be selected as a treatment option, especially in pediatric patients with AA or when there is a contraindication to ILCS injection.

Financial support and sponsorship

Nil.

Conflicts of interest

There are no conflicts of interest.