A 50 years man, B. Asthma since childhood, taking inhaled steroids and oral bronchodilators off and on round the year. Now from six months, he has developed black coloured skin lesions at axilla, soles of feet, on pinna of one ear, over suprapubic Area, inner sides of the both thighs.

He didn't showed improvement with anti fungal treatment. What is this skin problem in asthma patient? How it should be treated?