Role of Tzanck Smear Cytology in Dermatology: A Clinicopathological Study

Introduction: Variety of lesions affecting the skin range from non specific dermatoses and inflammatory lesions to neoplastic changes in different components of the skin tissue. Tzanck smear is a simple, easy, rapid and inexpensive diagnostic technique which now being used for the diagnosis of erosive vesiculobullous lesions, tumours, granulomatous lesions and cutaneous infections.

Aim: To compare between the clinical diagnosis and Tzanck smear cytology diagnosis.

Materials and Methods: It was a cross-sectional study on Tzanck smears, conducted at a tertiary care referral Institute, PES Institute of Medical Sciences and Research (PESIMSR), Kuppam, Andhra Pradesh, India, from March 2016 to April 2017. In each case, Tzanck smear cytology diagnosis and clinical diagnosis was documented and compared with each other and with that of the available histopathological diagnosis. The clinicopathological concordance was calculated. All statistical calculations were done through Microsoft (MS) Excel 2007.

Results: Total of 50 cases of Tzanck smears were analysed. On Tzanck smear cytology, the common diagnostic entities included cutaneous infections and non specific inflammatory lesions each constituting 22 cases (44%). When compared with the Tzanck smear diagnosis, the diagnostic accuracy of clinical diagnosis was 60% on applying partial concordance criteria. When compared with the histopathological diagnosis, the diagnostic accuracy of clinical diagnosis and Tzanck smear cytology diagnosis were 66.67% and 83.33%, respectively on applying partial concordance criteria.

Conclusion: Tzanck smear is a prudent diagnostic tool for cytological evaluation of cutaneous lesion. It serves as a complimentary investigative modality to histopathology.