dermatophytosis is a common clinical entity characterized by the infection of keratinized tissues such as skin , hair , and nails .
these dermatophytes are closely related filamentous fungi and cause the disease by virtue of their unique ability to degrade keratin and invade the skin and its appendages .
dermatophytic infections are of major importance , as they are widespread and cause discomfort . reactions to dermatophyte infection may range from mild to severe .
the mildness and severity depend on a variety of factors such as the host reactions to the metabolic products of the fungus , the virulence of infecting species or particular strain , anatomical location of the infection and local environmental factors .
dermatophytic infections are a common clinical problem encountered in more than 50% of patients attending the dermatology outpatient departments .
overcrowding , poor hygiene , low standards of living along with high humidity environments are contributing to the increased prevalence of these fungal infections .
the present study was conducted to know the prevalence , etiology and common clinical presentations of dermatophytosis involving skin and hair .
a total of 110 samples which included 101 skin samples and 9 hair samples , from clinically suspected to have dermatophytosis were collected .
a detailed history regarding age , sex , occupation , social status , duration of complaint and others were taken .
samples were collected after cleaning the affected surface with 70% alcohol . from skin lesions ,
scales were collected from erythematous growing margins of the lesion with a sterile blunt scalpel , and in case of tinea capitis , hairs were plucked with sterile surgical forceps .
samples were collected in sterilized whatman filter paper envelope and transported to the microbiological laboratory .
direct examination of fungal elements from skin scales and hair samples was done by using 10% and 20% koh mounts respectively .
all the samples were cultured on sabouraud 's dextrose agar ( sda ) with gentamicin and cycloheximide ( sda with actidione ) and dermatophyte test medium ( dtm ) ( hi - media ) .
fungal growth was identified by colony morphology ; pigment production and microscopic examination by tease mount technique in lactophenol cotton blue .
urease test and in - vitro hair perforation tests were also performed to differentiate trichophyton rubrum and trichophyton mentagrophytes when there was difficulty in identification by microscopic and macroscopic examination .
samples were collected after cleaning the affected surface with 70% alcohol . from skin lesions ,
scales were collected from erythematous growing margins of the lesion with a sterile blunt scalpel , and in case of tinea capitis , hairs were plucked with sterile surgical forceps .
samples were collected in sterilized whatman filter paper envelope and transported to the microbiological laboratory .
direct examination of fungal elements from skin scales and hair samples was done by using 10% and 20% koh mounts respectively .
all the samples were cultured on sabouraud 's dextrose agar ( sda ) with gentamicin and cycloheximide ( sda with actidione ) and dermatophyte test medium ( dtm ) ( hi - media ) .
fungal growth was identified by colony morphology ; pigment production and microscopic examination by tease mount technique in lactophenol cotton blue .
urease test and in - vitro hair perforation tests were also performed to differentiate trichophyton rubrum and trichophyton mentagrophytes when there was difficulty in identification by microscopic and macroscopic examination .
all the samples were cultured on sabouraud 's dextrose agar ( sda ) with gentamicin and cycloheximide ( sda with actidione ) and dermatophyte test medium ( dtm ) ( hi - media ) .
fungal growth was identified by colony morphology ; pigment production and microscopic examination by tease mount technique in lactophenol cotton blue .
urease test and in - vitro hair perforation tests were also performed to differentiate trichophyton rubrum and trichophyton mentagrophytes when there was difficulty in identification by microscopic and macroscopic examination .
males were more predominant 74 ( 67.27% ) compared to females 36 ( 32.73% ) .
more number of cases were observed between age groups of 2140 years 71 ( 64.54% ) [ table 1 ] .
clinical presentations of dermatophytosis observed were tinea corporis 44 ( 40% ) , followed by t. corporis with cruris 28 ( 25.45% ) , tinea cruris 10 ( 9.09% ) , tinea capitis 9 ( 8.19% ) , tinea faciei 7 ( 6.36% ) , tinea manuum 6 ( 5.45% ) , tinea pedis 5 ( 4.55% ) and tinea barbae 1 ( 0.91% ) .
t. corporis and t. corporis with cruris were more common in the age groups of 2140 years .
age- and sex - wise distribution of cases fungal elements by koh mount were observed in 64 ( 58.18% ) and culture was positive in 62 ( 56.36% ) .
of 64 ( 58.18% ) koh positive cases 55 ( 85.9% ) yielded growth in culture . among koh negative 46 ( 41.82% ) cases , 7 ( 15.2% ) were culture positive .
culture positivity was highest in t. corporis ( 38.71% ) and no culture positivity was noted in tinea barbae and tinea pedis .
dermatophytic species isolated were t. rubrum 58.06% [ figure 1 ] , t. mentagrophytes 22.58% [ figure 2 ] , epidermophyton floccosum 6.45% [ figure 3 ] , trichophyton violaceum 6.54% [ figure 4 ] , trichophyton tonsurans 3.22% [ figure 5 ] and trichophyton schoenleinii 3.22% [ figure 6 ] . 

( c ) lacto phenol cotton blue mount showing tear drop shaped microconidia ( 400 ) .
( d and e ) lacto phenol cotton blue mount showing pencil shaped macroconidia ( 400 ) 
 trichophyton mentagrophytes .
( d ) lacto phenol cotton blue mount showing nodular organ ( 400 ) 
 epidermophyton floccosum .
( c and d ) lacto phenol cotton blue mount showing club shaped macroconidia ( 400 ) .
( e ) lacto phenol cotton blue mount showing characteristic chlamydospores ( 400 ) 
 trichophyton violaceum .
( a ) growth on sabouraud 's dextrose agar ( obverse with violet color pigmentation ) .
( b ) lacto phenol cotton blue mount showing hyphae with chains of chlamydospores ( 400 ) trichophyton tonsurans .
( d ) lacto phenol cotton blue mount showing match stick like microconidia ( 400 ) .
( e ) lacto phenol cotton blue mount showing macroconidia ( 400 ) 
 trichophyton schoenleinii .
lacto phenol cotton blue mount showing antler hyphae and chlamydospores ( 400 ) t. rubrum was predominantly recovered in each clinical presentation but t. violaceum was the most common isolate in tinea capitis , followed by t. rubrum , t. tonsurans and t. schoenleinii [ table 2 ] .
dermatophyte species causing different clinical presentations all culture positives were grown both on sda with actidione and dtm on primary isolation .
on dtm first appearance of growth was within 10 days of inoculation for most of the isolates that is , 56 ( 90.32% ) [ figure 7 ] .
but , the appearance of growth was only after 10 days for most of the isolates when grown on sda with actidione 57 ( 91.94% ) . species level identification on primary isolation was possible for 42 ( 67.74% ) of culture positives when grown on sda with actidione .
but , no culture positive was identified up to species level from dtm on primary isolation .
( f ) trichophyton violaceum 
  among culture positive cases 19.35% were from rural area , and 80.65% were from urban area and 67.74% were from low socio - economic status , 30.65% were from middle socioeconomic status and 1.61% were from high socioeconomic status . in this study ,
8.06% of patients were diabetics , 6.45% were anemic , 3.23% of patients had a history of atopy and 1.61% were hiv positive .
use of occlusive or synthetic fabric dressing regularly was there in 40.32% of patients and 32.25% of patients were in contact with soil regularly because of their occupation .
all culture positives were grown both on sda with actidione and dtm on primary isolation .
on dtm first appearance of growth was within 10 days of inoculation for most of the isolates that is , 56 ( 90.32% ) [ figure 7 ] .
but , the appearance of growth was only after 10 days for most of the isolates when grown on sda with actidione 57 ( 91.94% ) . species level identification on primary isolation was possible for 42 ( 67.74% ) of culture positives when grown on sda with actidione .
but , no culture positive was identified up to species level from dtm on primary isolation .
( f ) trichophyton violaceum 
  among culture positive cases 19.35% were from rural area , and 80.65% were from urban area and 67.74% were from low socio - economic status , 30.65% were from middle socioeconomic status and 1.61% were from high socioeconomic status . in this study ,
8.06% of patients were diabetics , 6.45% were anemic , 3.23% of patients had a history of atopy and 1.61% were hiv positive .
use of occlusive or synthetic fabric dressing regularly was there in 40.32% of patients and 32.25% of patients were in contact with soil regularly because of their occupation .
in this study , highest incidence of dermatophytosis was observed in the age group of 2140 years and in males .
this may be due to greater physical activity and increased sweating in this age group favoring the growth of dermatophytes .
t. corporis , followed by t. corporis with cruris were common clinical presentations of dermatophytosis in the present study which was in correlation with other studies from india .
t. capitis was more common in children below the age group of 10 years , which was also observed in some studies .
t. rubrum was the most common dermatophyte to cause all clinical types of dermatophytoses followed by t. mentagrophytes .
chronic nature of infection and adaptation to human is mainly responsible for predominance of t. rubrum to cause dermatophytosis .
t. violaceum was predominant species to cause tinea capitis , followed by t. rubrum , t. tonsurans and t. schoenleinii .
culture positivity was more in koh positive cases 85.9% compared to koh negative cases 15.2% .
this difference is statistically significant  = 55.29 ; p < 0.001 , this shows that direct microscopy by koh mount is a good screening test in the laboratory diagnosis of dermatophytosis .
efficacy of sda with actidione and dtm in isolation of dermatophytes is equal in the present study .
this was in correlation with the study of singh and beena who reported that 96.55% of culture positives were grown on sda and 98.3% of culture positives were grown on dtm . but
dermatophytes grow earlier on dtm compared to sda with actidione . in the present study even though all 62 culture positive samples yielded growth both on sda with actidione and dtm on primary isolation , appearance of growth was earlier on dtm that is , within 10 days ( 90.32% ) compared to sda with actidione ( 8.06% ) .
for species level identification of dermatophytes , sda with actidione is preferable compared to dtm . in the present study ,
species level identification was possible for 67.74% of isolates on primary isolation on sda with actidione .
but species level identification was not possible with the growth on dtm on primary isolation , as conidial production was low on dtm , which is required for identification . moreover , it was not possible to observe pigment production on dtm . for identification of growth on dtm ,
dermatophytic infections were more common in people living in urban areas ( 80.65% ) compared to rural areas ( 19.35% ) .
this may be because the study included patients attending the outpatient department of dermatology of tertiary care teaching hospital , where most of the people were from the urban area .
high incidence of dermatophytic infections was observed in the low socioeconomic group of people ( 67.74% ) .
this is because of unhygienic living conditions , overcrowding , illiteracy and poor nutrition among them .
daily wage workers ( 35.48% ) and students ( 33.87% ) were predominantly affected compared to others .
this could be because of increased physical activity and hot environmental conditions which results in increased sweating and excessive moisture favoring the growth of dermatophytes .
this is in correlation with the study of prasad et al . in the present study
systemic predisposing factors like diabetes ( 8.06% ) , anemia ( 6.45% ) , atopy ( 3.23% ) , and hiv ( 1.61% ) were observed which are in correlation with other authors . local predisposing factors like occlusive or synthetic fabric dressing in 40.32% and contact with soil regularly because of their occupation in 32.25% were noted .
dtm is a good screening medium in laboratory diagnosis of dermatophytosis compared to sda with actidione .
 introduction : dermatophytic infections are commonly encountered a problem and constitute more than 50% of cases in dermatology outpatient departments . 
 diagnosis of these infections requires the proper use of laboratory methods.objectives:this study was conducted to know the etiology of dermatophytosis in patients attending tertiary care level hospital in south india and to compare the efficacy of sabouraud 's dextrose agar ( sda ) with actidione and dermatophyte test medium ( dtm ) in isolating and identifying dermatophytes.materials and methods : a total of 110 samples which included 101 skin samples and 9 hair samples from clinically suspected dermatophytosis were collected . 
 direct microscopy by koh and culture on sda with actidione and dtm were done.results:of 110 samples collected , 58.18% were koh positive for fungal filaments and 56.36% were culture positive for dermatophytes . 
 more number of cases were observed between age groups of 2140 years . 
 males were more affected compared to females . 
 tinea corporis was the common clinical presentation observed ( 40% ) . 
 trichophyton rubrum ( 58.06% ) was the predominant isolate recovered in all clinical presentations but trichophyton violaceum was the most common isolate in tinea capitis . 
 all culture positives were grown on both sda with actidione and dtm . 
 appearance of growth was earlier on dtm that is , within 10 days compared to sda with actidione where growth started appearing only after 10 days . 
 this is statistically significant p < 0.0001 ( 2 = 71.6 ) . 
 species level identification on primary isolation was possible when grown on sda with actidione and it was not possible with the growth on dtm on primary isolation.conclusion:dtm is a good screening medium in laboratory diagnosis of dermatophytosis when compared to sda with actidione . 
 but dtm is inferior to sda with actidione in identification of dermatophyte species . 