Blister Beetle Dermatitis: Few Observations Helping in Diagnosis

DEAR EDITOR Blister beetle dermatitis is an irritant contact dermatitis, caused when beetles of the genus Paederus are crushed on the skin, releasing the vesicant pederin. It is also known as Dermatitis Linearis or Paedrous Dermatitis. It is characterized by the presence of erythematous and edematous lesions, pain and burning sensation, blisters, pustules and kissing lesions. Though blister beetle dermatitis is a clinical diagnosis, at times it becomes difficult to identify it. Differential diagnosis of Blister beetle dermatitis include Herpes simplex, H zoster, allergic or irritant contact dermatitis, Bullous impetigo and phyto photo dermatitis. Authors have observed that in many cases of blister beetle dermatitis, even on mild touch over the affected area, patient will feel burning sensation and he will immediately pull back the touched body part. This sign may be named as “Pull back sign of Ashish”. This sign may be positive in few other conditions with localized hyperesthesia. It may be due to voluntary reaction due to hyperesthesia over inflamed area. This sign helps a lot in suspected cases of blister beetle dermatitis, where diagnosis is confusing. Authors would like to share one more observation that on touching a lesion of blister beetle Source of Support: Nil, Conflict of Interest: None declared. Department of Dermatology and Venereology, Jawahar Lal Nehru Hospital and Research Centre, Bhilai, Chattisgarh, India, 1Department of Neurology, Dr. Ram Manohar Lohia Institute of Medical Sciences, Vibhooti Khand, Gomti Nagar, Lucknow Uttar Pradesh, India, 2Department of Geriatic Medicine, King George Medical University, Lucknow, India, 3Department of Dermatology, Venereology and leprology, MGMCRI, Pondicherry, India Correspondence to: Dr. Ashish Singh, Departments of Dermatology and Venereology, Jawahar Lal Nehru Hospital and Research Centre, Bhilai, Chattisgarh ‐ 490 009, India. E‐mail: [email protected]