Tzanck smears: an old but useful diagnostic tool

Abstracts

A citologia de Tzanck consiste em método simples e confiável para o diagnóstico de dermatoses virais, parasitárias, autoimunes e tumorais. Para exemplificar o emprego do teste de Tzanck em lesões vésico-bolhosas, um caso de pênfigo vulgar é descrito, cuja citologia e imunofluorescência direta, utilizando-se esfregaço coletado de lesão oral, confirmaram o diagnóstico de forma rápida e fácil.

Citologia; Imunofluorescência; Pênfigo

COMMUNICATION

Tzanck smears: an old but useful diagnostic tool

Moema Mignac Cumming Brito^I; Daniela Chaves Tarquínio^II; Darlene Arruda^III; Roberto Silva Costa^IV; Ana Maria Roselino^V

^IMD – Specialist in Dermatology, Hospital das Clínicas, Faculdade de Medicina de Ribeirão Preto (FMRP-USP) – São Paulo (SP), Brazil

^IIMD - Specialist in Dermatology, MSc student, Faculdade de Medicina de Ribeirão Preto (FMRP-USP) – São Paulo (SP), Brazil

^III MD (in memoriam) - Staff, Pathology Department, Hospital das Clínicas, Faculdade de Medicina de Ribeirão Preto (FMRP-USP) – São Paulo (SP), Brazil

^IVMD, PhD - Professor, Department of Pathology, Hospital das Clínicas, Faculdade de Medicina de Ribeirão Preto (FMRP-USP) – São Paulo (SP), Brazil

^VMD, PhD - Associate Professor, Division of Dermatology, Internal Medicine Department, Faculdade de Medicina de Ribeirão Preto (FMRP-USP) – São Paulo (SP), Brazil

^{Mailing Address}

ABSTRACT

Tzanck smears can be used for the diagnosis of cutaneous infections, autoimmune disorders and cutaneous tumors. To exemplify its use, we report a case of a female patient with pemphigus vulgaris whose diagnosis was confirmed by positive direct immunofluorescence and conventional cytology using smears obtained by scraping the cheek mucosa.

Keywords: Cytology; Fluorescent antibody technique; Pemphigus

Cytology, which studies individual cells, their intrinsic characteristics and their functions, is a relatively new science. George Papanicolaou is considered the father of exfoliative cytology, but, in 1947, it was Tzanck who used diagnostic cytology for the first time, using it in vesicular-bullous dermatoses, especially herpes simplex. Dermatologists have used cytodiagnosis little in their routine, although in experienced hands, skin or mucosa smears may be simple, fast, cheap and reliable for the diagnosis of many dermatological diseases of a variety of etiologies. Its use has been restricted to researching for multinucleated squamous cells suggestive of viral inclusions in oral mucosa lesions or when eczema vaccinatum is suspected.^1,2

The diagnosis of genodermatoses, skin infections, autoimmune conditions, and tumors may be made through the observation of characteristic cytological findings (Chart 1). In relation to bullous dermatoses, the acantholytic cells shown in the mucosa lesion smear of pemphigus vulgaris (PV) received the denomination of Tzanck cells.³ The presence of acantholytic cells indicates, but is not specific to PV. Some authors have tried to evaluate the role of direct immunofluorescence (DIF) in Tzanck smears to diagnose PV. DIF results performed in cytological smears and conventional skin biopsies of the same group of patients, were concordant for both samples.⁴

In order to show the application of the Tzanck test in bullous dermatosis, following, we will describe a clinical case, whose cytology and DIF of a smear collected from an oral lesion, confirmed the diagnosis of PV. In brief, a female, 49 year-old patient from the northeast region of the state of São Paulo, had been presenting erosive lesions in the oral mucosa, associated with odinophagia, and lesion in the vaginal mucosa for two years. After three months, tense bullae of hyaline content in the tegument emerged. The dermatological exam presented ex-ulcered lesions in the hard palate, cheek mucosa and peri-alveolar gingival mucosa, in addition to lenticular to nummular eroded lesions in underarms, back, abdomen and inguinal region. The Nikolsky sign was present. Cheek mucosa scraping was collected using a longitudinally cut wood spatula, laid as a smear on two slides. One was immediately fixed in 70º ethanol for conventional cytology, and the other was stored in a common freezer for DIF. The cytological smear showed findings compatible with pemphigus, and the DIF showed anti-IgG deposit between keratinocytes. A skin biopsy was performed and due to the findings of suprabasal acantholysis, a diagnosis of PV was confirmed. Due to the complaint of odinophagia, the patient was submitted to high digestive endoscopy, which led to the diagnosis of chronic acantholytic esophagitis based on the esophagic biopsy sample (Figure 1).

In initial stages of PV, the Tzanck smear has shown to be a very useful tool, since it is known that patients frequently begin the picture of PV with mucosa lesions, as reported in the present patient, and the diagnosis should be established as fast as possible for the treatment to be initiated, given its severity. The cytological smear, also used for DIF, to diagnose PV is particularly important in anatomical regions of difficult access, such as lesions in the oral cavity and genital regions. Some authors emphasize that DIF has prognostic value, and that finding a positive DIF during remission of pemphigus may mean a potential recurrence in comparison to a negative DIF.^4,5

It is emphasized that using Tzanck citology in bullous dermatoses may be extended to the skin lesions of pemphigus foliaceus, endemic in Brazil.6 By collecting duplicate skin or mucosa samples, performing cytology plus DIF in the smear may be used for routine assessment of diagnosis and prognosis, given it is a cheap and easy method to be performed. In this sense, sites with more precarious laboratory resources may benefit from such technique, given that DIF performed on a skin biopsy requires more expensive equipment, such as the use of microtomes and specialized techniques.

In this way, despite being old method, it is clear that there still is room for cytology in the diagnosis of many dermatoses,⁷ in an era in which diagnostic procedures in all medical specialties are multiplying themselves fast, becoming increasingly refined and also increasingly expensive for patients.

REFERENCES

Conflict of interest: None

Financial funding: Faepa (Fundação de Apoio ao Ensino, Pesquisa e Assistência) e Hospital das Clínicas (FMRP-USP).

How to cite this article: Brito MMC, Tarquínio DC, Arruda D, Costa RS, Roselino AM. Citologia de Tzanck: redescobrindo uma antiga ferramenta diagnóstica. An Bras Dermatol. 2009;84(4):431-3.

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• 3. Gupta LK, Singhi MK. Tzanck smear: a useful diagnostic tool. Indian J Dermatol Venereol Leprol. 2005; 71:295-9
• 4. Aithal V, Kini U, Jayaseelan E. Role of direct immunofluorescence on Tzanck smears in pemphigus vulgaris. Diagn Citopathol. 2007;35:403-7
• 5. Ratnam KV, Kang BK. Pemphigus in remission: value of negative direct immunofluorescence in management. J Am Acad Dermatol. 1994;30:547-50
• 6. Chiossi MPV, Roselino AMF. Endemic pemphigus foliaceus (Fogo selvagem): a series from the Northeastern region of the State of São Paulo, Brazil, 1973-1998. Rev Inst Med Trop Sao Paulo. 2001;43:59-62
• 7. Durdu M, Baba M, Seçkin D. The value of Tzanck smear test in diagnosis of erosive, vesicular, bullous, and pustular skin lesions. J Am Acad Dermatol. 2008;59:958-64

Publication Dates

• Publication in this collection
  19 Oct 2009
• Date of issue
  Aug 2009