Dermoscopic Findings and Assessment of Treatment Response in Patients with Tinea Incognito: A Pilot Study

Abstract

Background:

Tinea incognito presents with atypical, widespread, and recurrent lesions. Dermoscopy can aid its rapid diagnosis.

Aim and Objectives:

This study aimed at assessing dermoscopic features and response to treatment in patients with tinea incognito.

Materials and Methods:

An evaluation of 62 patients with tinea of glabrous skin (Group A (cases)—31 steroid modified and Group B (controls)—31 treatment naïve) was done. Clinical, dermoscopic, and mycological evaluations were done for both groups at baseline, 2, and 4 weeks of terbinafine therapy. Clinical severity (Clinical Assessment Severity Score (CASS) and Visual Analogue Scale (VAS)) and frequency of various dermoscopic changes were compared at 0 and 4 weeks between cases and controls, using unpaired Student’s t-test, Mann–Whitney U-test, and Wilcoxon signed-rank test.

Results:

Baseline dermoscopic features for both groups were significantly different with respect to frequency of broken hair, bent hair, micropustules and Morse code hair. Earliest feature to resolve with treatment was micropustules at 2 weeks. Significant reduction in frequency of morphologically altered hair was evident at 4 weeks. Telangiectasia, dotted vessels, I-hair, and broken hair persisted for a longer period of time. Terbinafine for 4 weeks was an effective treatment, producing complete cure in 73% of cases and 93% of controls. Persistent dermoscopic changes at 2 weeks were found to be associated with treatment failure at 4 weeks, highlighting the role of dermoscopy in identifying patients requiring prolonged treatment.

Conclusions:

Dermoscopy can be used as a diagnostic and monitoring tool for tinea of glabrous skin.

Introduction

Superficial dermatophytoses affect 20–25% of the world’s population. They have shown an increasing trend over the past few years resulting in an epidemic like situation, especially in the tropics.[1,2] Tinea incognito refers to an atypical presentation of superficial dermatophytoses, commonly associated with use of topical or systemic corticosteroids.[1,2]

Dermatophyte infections are usually diagnosed clinically. Diagnostic tests include direct microscopy on potassium hydroxide (KOH) mount (mostly used for screening) or fungal culture (diagnostic gold standard). However, it can take 3–4 weeks to obtain the culture results, leading to a delay in treatment. Dermoscopy has been found useful in diagnosis of tinea infections, especially that of hair and nails. However, dermoscopic features of tinea incognito have not been well evaluated, with only isolated case reports and small case series being available.[3,4,5,6,7] Dermoscopy as a monitoring tool for assessing treatment response has also not been well explored.

Materials and Methods

We conducted an interventional, case–control study involving patients with tinea of glabrous skin, after obtaining institutional ethical clearance. A total of 62 patients, diagnosed with tinea corporis (KOH positive), were recruited over 18 months, after explaining the study protocol and obtaining written informed consent. They were divided into two groups: Group A (cases) included patients with tinea incognito (steroid modified), while Group B (controls) included patients with treatment naïve infection. All cases were confirmed with a positive direct microscopy (potassium hydroxide or KOH mount).

Participants were subjected to a detailed history and examination. The baseline disease severity was objectively graded using Clinical Assessment Severity Score (CASS), evaluated by quantifying erythema, atrophy, scaling, pustulation, and advancing border designated on a scale of 1 to 3, with a maximum additive score of 15 and Visual Analogue Scale (VAS) that evaluates pruritus severity according to the patient’s perception of itch ranging from 0 to 10. Dermoscopic evaluation was done with a USB dermatoscope (AM77515 Dino-lite edge; Anmo Corporation, Taiwan) at baseline. The number of morphologically altered hair in a diameter of 4 cm circle at the most representative site was counted, and the same site was revaluated to look for response to treatment. The frequency of various dermoscopic findings was recorded.

Samples were obtained for fungal culture on Sabouraud’s dextrose agar (SDA) media, to enable species identification. It was repeated at 4 weeks.

All patients were initiated on terbinafine 250 mg twice daily after ruling out any contraindications. They were subsequently evaluated at weeks 2 and 4. At each visit, clinical improvement was assessed using CASS and VAS. Patients with clinical activity at week 4 were continued on terbinafine and followed up till 8 weeks. Non-responders were shifted to oral itraconazole at 8 weeks and followed up till cure. Clinical cure was defined as CASS falling to <3, while mycological cure was based on a negative KOH and culture at end of 4 weeks. Complete cure was defined as a combination of both clinical and mycological cure.

Statistical analysis

The data was analyzed by statistical software SPSS version 20.0. Continuous variables were reported as mean (SD) or median (25^th–75^th percentile) and quantitative data with numbers and percentages. Demographic data was compared between groups using unpaired Student’s t-test and Chi-square test for other variables between cases and controls. The frequency of dermoscopic hair changes was compared using Mann–Whitney U-test and Wilcoxon signed-rank test. The changes in dermoscopic parameters following improvement between the groups were compared with the z-test for proportion. A comparison between VAS and CASS scores was performed between groups using unpaired Student’s t-tests and from baseline to 4 weeks values using repeated measure analysis of variance. The P value was adjusted for the Bonferroni comparison. The rate of improvement over time was observed using a linear mixed model, taking VAS as the dependent variable and number of weeks as the continuous variable, group as a factor, with interaction between the groups and weeks also being included in the model. A P value less than 0.05 was considered significant.

Results

Demographic characteristics of the patients in Group A and Group B were significantly different, as is depicted in Table 1. Group A patients were younger, more likely to be of lower socioeconomic class, engaged in outdoor work, and giving history of wearing occlusive clothes and past history of tinea. The most common site of involvement was crurae (100%) in both groups, followed by trunk [74.1% in Group A and 12.9% in Group B] and face [38.7% in Group A and 9.6% in Group B]. The involvement of nails (9.6%) and feet (6.4%) was seen only in Group A patients. In Group A, 93.5% of patients had ≥2 sites involved that was much higher than Group B (22.5%). Additionally, Group A patients presented with varied presentations including steroid abuse facies (32.2%), lichenoid lesions (29%), pseudoimbricata lesions (9.6%), eczematous presentation (9.6%), and pityriasis rosea like and granuloma annulare like lesions (6.4% each), whereas all Group B patients presented with classical, annular, erythematous, scaly plaque with central clearing.

Table 1.

Demographic data of patients in cases and control

Parameters	Cases (n=31) (Group A)	Control (n=31) (Group B)	P (Chi-square test)
Age mean (SD)	30.3±9.9	23.6±7.4	0.004*
SES (UL + L)	28 (90.3%)	14 (45.2%)	0.0004
Outdoor workers	21 (67.7%)	9 (29%)	0.002
Occlusive clothing	30 (96.7%)	20 (64.5%)	0.001
Clothes sharing	26 (83.8%)	18 (58%)	0.02
Soap use	15 (48.3%)	26 (83.8%)	0.003
Pets	5 (16.1%)	3 (9.6%)	0.7
Past history of tinea	13 (36%)	4 (12%)	0.01
Family history of tinea	16 (51.6%)	10 (32.2%)	0.1

n=Total number of patients enrolled, SES=Socioeconomic status based on modified Kuppuswamy scale (upper lower + lower), P<0.05 is significant, SD=Standard deviation; *Unpaired Student’s t-test

Clinical objective parameters

Mean VAS score for pruritus was higher at baseline for Group B (8 ± 0.9) as compared to Group A (6.8 ± 1; P value < 0.001). The difference remained significant at 2 and 4 weeks as well, after adjusting for the baseline VAS score, but was higher for Group A. The decline in the score over a period of 4 weeks was much sharper in Group B (8 to 3.5) as compared to Group A (6.8 to 5). A mean decline of -0.44 per week was recorded for Group A, while it was -1.14 per week for Group B. This difference was also statistically significant [Figure 1].

Figure 1.

Mean VAS score for pruritus between group A and B at weeks 0, 2, and 4 respectively

Mean CASS was comparable for Groups A and B at baseline. The decline in CASS at 2 and 4 weeks was steeper for Group B (5.0 → 1.7 → 0.94) as compared to Group A (5.3 → 3.3 → 1.87). The difference between groups was statistically significant at both 2 weeks and 4 weeks (P value < 0.01). According to repeated measure analysis of variance, the rate of decrease was significant in both groups, and the trend was found to be similar at -0.94 per week [Figure 2]. Rates of clinical cure were comparable between groups (P value = 0.1), being achieved in 77.4% patients in Group A and 93.5% in Group B.

Figure 2.

Mean CASS score between group A and B at weeks 0, 2, and 4 respectively

Direct microscopy examination

At the end of 4 weeks, KOH mount for 22.5% of Group A patients remained hyphae positive, whereas all became hyphae negative in Group B (P value < 0.01).

Fungal culture

A higher culture positivity rate was observed for Group A (90.3%) as compared to Group B (80.6%) (P = 0.4). In decreasing order of frequency, the species isolated were Trichophyton mentagrophyte complex in 75% of Group A patients and 92% of Group B patients, followed by Trichophyton violaceum in 14.2% and 8%, respectively. Microsporum canis was observed only in Group A in 10.7% patients; all of whom gave history of exposure to pets in the family.

At the end of 4 weeks, 7 (22.5%) Group A patients and 2 (6.4%) Group B patients remained culture positive. All had a partial clinical response (≥50%) to terbinafine and were thus continued on the same drug till 8 weeks. At 8 weeks, five patients in Group A and both in Group B had achieved complete cure. Remaining two patients in the Group A were shifted to itraconazole. These were followed up till complete cure.

Dermoscopic features

Dermoscopic findings noted in the current study at baseline (0 weeks) were diffuse erythema, follicular micropustules, telangiectasias, dotted vessels, and perifollicular scaling. Features of hair invasion noted were brown spots surrounded by white/yellow halo, corkscrew hair, Morse code hair, I hair, broken hair, bent hair, and translucent hair. In Group A, translucent hair 29 (93.5%) and broken hair 27 (87%) were the most common dermoscopic finding of vellus hair involvement, followed by Morse code hair 26 (83.8%), I hair (24 (77.4%), bent hair 23 (74.1%), brown spot with yellow white halo 21 (67.7%), and corkscrew hair and perifollicular scaling 17 (54.8%). Most common dermoscopic finding in Group B was that of bent hair and brown spot with yellow white halo 27 (87%) and translucent hair 23 (74.1%) followed by broken hair 18 (58%), Morse code hair 17 (54.8%), corkscrew hair and perifollicular scaling (9, 29%) each, and I hair 6 [19.3%; Table 2]. The groups were significantly different with respect to the frequency of broken hair, bent hair, Morse code hair, and micropustules at baseline.

Table 2.

Comparison of dermoscopic findings in tinea incognito and naïve tinea with other studies

Comparison	Our study Tinea incognito (n=31)	Bhat et al.[8] 2019 Tinea incognito (n=38)	Our study Naïve tinea (n=31)	Bhat et al.[8] 2019 Tinea cruris (n=30)	Gomez-Moyano et al.[7] (2010) Tinea incognito (n=6)
BH	27 (87%)		18 (58%)		3 (50%)
Erythema	31 (100%)	13 (34.2%)	31 (100%)	30 (100%)
Be.H	23 (74.1%)	15 (39.4%)	27 (87%)	4 (13.5%)
TH	29 (93.5%)		23 (74.1%)		5 (83%)
MCH	26 (83.8%)	18 (47.3%)	17 (54.8%)	8 (26.6%)	1 (17%)
CSH	17 (54.8%)		9 (29%)		1 (17%)
IH	24 (77.4%)		6 (19.3%)
PFS	17 (54.8%)		9 (29%)
MP	24 (77.4%)	14 (36.8%)	6 (19.3%)	11 (36.6%)	4 (67%)
BS with YH (globules)	21 (67.7%)		27 (87%)	6 (20%)
Telangiectasia	31 (100%)		4 (12.9%)
DV	31 (100%)		4 (12.9%)
Atrophy	8 (25.8%)		0

n=Number of patients enrolled, BH=Broken hair, Be.H=Bent hair, TH=Translucent hair, MCH=Morse code hair, CSH=Corkscrew hair, IH=I hair, PFS=Perifollicular scaling, MP=Micropustules, BS with YH=Brown spot with yellow halo, DV=Dotted vessels

Dermoscopic follow-up

Follow-up showed resolution of micropustules (77.4% to 0 in Group A and 19.3% to 0 in Group B) to be the earliest change, seen at 2 weeks (P < 0.001). It was followed by resolution of perifollicular scaling (54.8% to 0 in Group A and 29% to 0 in Group B) at 4 weeks. The reduction in erythema (100% to 9.6% in Group A and 100% to 6.4% in Group B) was comparable in both the groups [Table 3].

Table 3.

Comparison of frequency of dermoscopic changes observed between treatment groups (Bonferroni adjusted)*

Variable	Group A (Tinea incognito) (n=31)			Group-B (Naïve tinea) (n=31)			Comparison of % change between the groups (Bonferroni adjusted)*
	Baseline (%)	2 weeks (%)	4 Weeks (%)	Baseline (%)	2 weeks (%)	4 weeks (%)	P (B vs 2 weeks	P (B vs 4 weeks)
Erythema	100	35.5	9.6	100	16.1	6.4	0.160	1.00
MP	77.4	0	0	19.3	0	0	<0.001	<0.001
PFS	54.8	54.8	0	29	6.5	0	0.012	0.078

n=Number of patients enrolled, PFS=Perifollicular scaling, MP=Micropustules. *Z-test for proportion and P value adjusted for Bonferroni correction

Dermoscopically, there was resolution of hair involvement in the majority of the Group A [Tables 4 and 5; Figure 3a and b] and Group B [Figure 4a and b] patients, with altered hair in Group A patients taking a longer time to resolve. Disappearance of brown spots with yellow halo (globules) was an early indicator of response to treatment, along with reduction in the median values for altered hair morphology in both the groups. Difference in frequency of broken hair, bent hair, and Morse code hair at baseline versus corkscrew hair and bent hair at 4 weeks were all statistically significant, with a higher involvement of vellus hair in Group A. The intragroup comparison of altered hair morphology showed notable and statistically significant improvement in broken hair, bent hair, corkscrew hair, translucent hair, and Morse code hair at 4 weeks [Table 5]. Dermoscopic findings like telangiectasia, dotted vessels, I-hair, translucent hair, and broken hair persisted for a longer period of time in 7 (22.5%)% of Group A and 2 (6.4%) of Group B patients, and notably, these findings were more prevalent in patients who were not cured clinically and mycologically at 4 weeks suggesting that these dermoscopic indicators may be associated with the need for a prolonged period of treatment of 6–8 weeks.

Table 4.

Intergroup comparison of frequency of altered hair morphology over the study duration

Hair morphology	Cases (Group A) 0 weeks	Control (Group B) 0 weeks	P “u”	Cases (Group A) 4 weeks	Controls (Group B) 4 weeks	P “u”
TH	6 [1-8]*	6 [5-6]	0.912	0 [0-3]	0 [0-1]	0.297
	4.84 (3.22)# n=29	5.74 (0.69) n=23		1.41 (2.20) n=29	0.52 (0.99) n=23
MCH	3 [3-4]	4 [3.5-5.0]	0.004	0 [0-1.3]	0 [0.0-0.0]	0.162
	3.31 (0.84) n=26	4.12 (0.78) n=17		0.73 (1.0) n=26	0.41 (1.0) n=17
CSH	3 [1-3]	3 [3-4]	0.095	0 [0-0.5]	0 [0-0]	0.043
	2.5 (1.16) n=17	3.3 (0.71) n=9		0.88 (1.15) n=17	0.0 (0.0) n=9
IH	3.0 [1.0-3.0]	2.5 [2.0-3.0]	0.826	0.5 [0.0-2.0]	0.0 [0.0-0.5]	0.237
	2.33 (1.00) n=24	2.5 (0.55) n=6		0.96 (1.20) n=24	0.33 (0.82) n=6
Be.H	4 [3-5]	5 [5-6]	<0.001	1 [0-2]	0 [0-2]	0.018
	3.87 (1.06) n=23	5.26 (1.0) n=27		1.17 (0.83] n=23	0.59 (0.89) n=27
BH	6 [2-8]	4 [3-5]	0.045	0 [0-3]	0 [0-0]	0.126
	5.33 (2.8) n=27	4.22 (1.00) n=18		1.3 (1.9) n=27	0.44 (1.04) n=18

BH=Broken hair, Be.H=Bent hair, TH=Translucent hair, MCH=Morse code hair, CSH=Corkscrew hair, IH=I hair. Median with interquartile range is used for comparison. *Median [25^th to 75^th percentile]; ^#mean (standard deviation); “u” Mann–Whitney U-test

Table 5.

Intragroup comparison of frequency of altered hair morphology over the study duration

Hair morphology	Cases (Group A) 0 week	Case (Group A) 4 weeks	P “u”	Control (Group B) 0 week	Control (Group B) 4 weeks	P “u”
TH	6 [1-8]*	0 [0-3]	<0.001	6 [5-6]	0 [0-1]	<0.001
	4.84 (3.22)# n=29	1.41 (2.20) n=29		5.74 (0.69) n=23	0.52 (0.99) n=23
MCH	3 [3-4]	0 [0-1.3]	<0.001	4 [3.5-5.0]	0 [0.0-0.0]	<0.001
	3.31 (0.84) n=26	0.73 (1.0) n=26		4.12 (0.78) n=17	0.41 (1.0) n=17
CSH	3 [1-3]	0 [0-0.5]	<0.001	3 [3-4]	0 [0-0]	0.002
	2.5 (1.16) n=17	0.88 (1.15) n=17		3.3 (0.71) n=9	0.0 (0.0) n=9
IH	3.0 [1.0-3.0]	0.5 [0.0-2.0]	<0.001	2.5 [2.0-3.0]	0.0 [0.0-0.5]	0.125
	2.33 (1.00) n=24	0.96 (1.20) n=24		2.5 (0.55) n=6	0.33 (0.82) n=6
Be.H	4 [3-5]	1 [0-2]	<0.001	5 [5-6]	0 [0-2]	<0.001
	3.87 (1.06) n=23	1.17 (0.83] n=23		5.26 (1.0) n=27	0.59 (0.89) n=27
BH	6 [2-8]	0 [0-3]	<0.001	4 [3-5]	0 [0-0]	<0.001
	5.33 (2.8) n=27	1.3 (1.9) n=27		4.22 (1.00) n=18	0.44 (1.04) n=18

BH=Broken hair, Be.H=Bent hair, TH=Translucent hair, MCH=Morse code hair, CSH=Corkscrew hair, IH=I hair. Median with interquartile range is used for comparison. * Median [25^th to 75^th percentile]; ^#mean (standard deviation); “u” Mann–Whitney U-test

Figure 3.

(a) Dermoscopic image from a Group A patient (Dino-lite edge, AM77515, 10X, polarized mode) showing erythematous background with scaling over the edge (blue arrow), dotted vessels (black circle), bent hair (blue circle and brown arrow), corkscrew hair (yellow arrow and black arrow), reddish brown dots and globules (light blue arrow), broken hair (green arrow), black dot (red arrow), perifollicular scale (purple arrow) with translucent hair (white arrow); (b) post-treatment dermoscopic image from the same patient (polarized mode) showing persistent dotted vessels (black arrow) with improvement in deformed hair morphologies (red arrow). Regrowing hair (blue circle) as well as empty hair follicle (blue arrow) is seen

Figure 4.

(a) Dermoscopic image from a Group B patient (Dino-lite edge, AM77515, 10X, polarized mode) showing mild erythema and scaling (black arrow), perifollicular scaling damaging hair shaft (red circle), hair follicle opening surrounded by yellow-brown halo (blue star), translucent hair (red arrow), coiled hair (blue arrow), and micropustules (yellow arrow); (b) post-treatment dermoscopic image from the same patient (Dino-lite edge, AM77515, 10X, polarized mode) showing resolution of erythema and scaling with improvement in hair morphology (black arrow) and regrowing hair (blue circle)

Discussion

A consistent upsurge in steroid modified tinea of glabrous skin (tinea incognito) infections is attributed to over-the-counter availability of cheap topical corticosteroids alone or in combination with antifungal agents, as irrational triple or quadruple combination. Steroid misuse includes continued application for weeks, months, and sometimes years, leading to chronicity, failure of treatment, difficult to diagnose tinea, and deeper and disseminated infection.[8,9] Further, steroid adverse reactions add to the disease burden and morbidity, thereby causing impairment of quality of life.[9]

In the present study, the mean reduction of CASS and VAS scores was significantly higher in Group B, with the differences remaining statistically significant at 2 and 4 weeks (P < 0.01 for both). This indicates a better and earlier response to terbinafine treatment in naive tinea as compared to incognito tinea. Previously, this type of clinical assessment scoring scale was used by Hernandez et al. as an assessment tool for comparative studies between griseofulvin and terbinafine during therapy of tinea corporis.[10] Voravutinon et al. used clinical assessment scoring with three parameters: scaling, erythema, and pruritus, and concluded that better clinical response was evident in the terbinafine group.[11] However, no previous study has compared the response to terbinafine treatment in tinea incognito patients with that of naive tinea patients, using CASS. Future studies can include this as an outcome measure.

Dermoscopic findings

The use of dermoscopy has been rapidly increasing over the years. For dermatophytosis, it does not substitute mycological examination, rather it complements it as an important non-invasive tool, aiding in the identification of vellus hair involvement. It can help identify the need for systemic therapy which at times may not be evident clinically.[7] Previously described dermoscopic features of tinea incognito include erythema, scaling, bent hair, Morse code hair, and micropustules [Table 2].[3,4,5,6,7,12] Our study adds another morphological finding to the previously described dermoscopic features of tinea incognito in the form of I-hair, which are otherwise reported as a dermoscopic feature of tinea capitis [Table 2]. We documented their presence in 77.4% patients of Group A and 19.3% patients of Group B. Dermoscopy of tinea corporis, cruris, and, incognito has not been described in detail in the literature. Knöpfel et al. reported a case of tinea corporis in an infant in whom dermoscopy helped determine vellus hair involvement, enabling a switch from topical to systemic antifungal therapy. They emphasized that dermoscopic features suggesting fungal invasion of hair follicle, such as follicular micropustules and brown spots surrounded by a white-yellowish halo, may help in therapeutic management.[3] In the present study, dermoscopic follow-up assessment was performed to evaluate the response to treatment, focusing on hair involvement and altered hair morphology and dermoscopy helped to identify the patients who needed to continue the systemic therapy for a longer period of time. This has not been described in any of the previous studies in literature. Dermoscopic follow-up in our study showed that micropustules were the earliest feature to resolve, at 2 weeks, followed by a more gradual resolution of perifollicular scaling, at 4 weeks. Erythema was more severe in the Group B initially (0 weeks), though the difference was not statistically significant. It took a longer time to resolve in Group A patients [Table 3]. Follow-up showed a better and earlier resolution of these findings in Group B patients, with altered hair morphology reducing over 4 weeks. Difference in frequency of broken hair, bent hair, and Morse code hair at baseline versus corkscrew hair and bent hair at 4 weeks was statistically significant, with a higher involvement of vellus hair in Group A [Table 4]. Least reduction was recorded in telangiectasias, dotted vessels, and atrophy, all being markers of steroid abuse. Altered hair morphology persisted longer in patients who did not go on to achieve cure at 4 weeks, both clinically and microscopically, reflecting the role of dermoscopy in identifying the poor responders. This suggests that dermoscopy can serve as an important tool in not only aiding diagnosis, but assessing response to treatment. Dermoscopic examination can predict from the outset which cases of tinea of vellus hair skin will respond poorly or even not respond at all to topical treatment alone.

Mycological profile

At the end of 4 weeks, culture positivity was present in 22.5% of patients in Group A and 6.4% in Group B. This could be attributed to failure of adequate family treatment, use of occlusive clothing, lack of adequate personal hygiene, or inadequate response to treatment. These factors can foster persistence and maintenance of infection in the family as well as the community. These are candidates for antimicrobial resistance testing. We could not correlate dermoscopic features with the causative fungi due to small sample size. Studies with a larger cohort of culture positive cases could elaborate on the association, if any.

Terbinafine was found to be effective with complete cure being seen in 85% of patients at 4 weeks (77% cases and 93% controls). This increased to 96% at 8 weeks. Previous studies have reported clinical cure rates varying from 71 to 100%. Not much of a significant difference was reported between griseofulvin and terbinafine; however, a higher relapse rate has been observed with griseofulvin in some studies.[13,14,15] A recent study from Varanasi, including 500 patients with dermatophytosis, showed a high terbinafine failure with an extremely low 30% cure rate at 4 weeks. The drug supply in the study was not uniform, and no assessment of compliance and adherence to treatment, culture, and antifungal susceptibility was done.[13,15] T Yamada et al. reported terbinafine resistance in Trichophyton due to a mutation in the squalene epoxide gene.[16] Sardana et al. reported resistance to terbinafine based on higher minimum inhibitory concentration (MIC) values, but no cases of microbiological resistance were documented.[17] In contrast, our study showed terbinafine to be effective against tinea. Future studies should include dermoscopic evaluation as a tool to decide requirement for continued therapy.

Conclusion

We conclude that dermoscopy is a useful non-invasive, office tool that can be used both for diagnosis as well as assessment of response to treatment of tinea of glabrous skin, thereby guiding the clinician regarding the need for continuation of systemic therapy. Contrary to some recent reports in literature, terbinafine was found to be an effective drug with a cure rate of 85% (4 weeks) and 96% (8 weeks) with a better clinical, mycological, and dermoscopic response in the corticosteroid naïve tinea patients. In patients with tinea of glabrous skin, eliciting family history, past history, and treatment history can help prevent recurrence and persistence of infection. Further studies with a larger sample size can help confirm our findings and evaluate possible association of dermoscopic features and treatment response, with causative species.

Financial support and sponsorship

Nil.

Conflicts of interest

There are no conflicts of interest.