RESUMO
Introduction: Tzanck Test (TT) is a sensitive method applicable to mucocutaneous lesions. Direct immunofluorescence (DIF) for Simplex Herpes Virus (HSV) is now a simple, no routine clinical laboratory practice, allows to differentiate the types of virus. Objectives: To evaluate the diagnostic sensitivity of Tzanck test vs DIF for herpetic lesions, and to know its usefulness as a complementary diagnostic tool to clinical skin lesions in patients with erosive, vesicular, bullous and pustular lesions. Materials and Methods: The TT was carried out in 157 lesion patient’s samples admitted to the Laboratory of Cytology of our Hospital from 1 January 2010 until 30 December 2014. Smears were stained with Giemsa and in parallel we performed DIF for HSV-1, HSV-2 and Varicella Zoster over 112 samples. Results: Of the total samples, 40 (25%) were unsatisfactory for cytodiagnosis. The TT was positive in 60 samples (38%), of which 55 (35%) showed cytopathic effect for Herpes virus, 2 (1.6%) samples showed characteristic inclusion bodies of Molluscum contagiosum infection (Henderson-Paterson bodies), 1 (0.6%) sample showed acantholytic cells typical of Pemphigus Vulgaris, 1 (0.6%) showed morphological characteristics of Incontinentia Pigmenti and 1 (0.6%) presented immature cells of lymphoid appearance. 64 samples were positive by DIF and 58 by TT for HSV. Specificity and sensitivity for TT were 100% and 88% respectively. Conclusion: The TT should be appreciated as a useful tool in the diagnosis of skin lesions by the rapid implementation and their ease interpretation, as well as being affordable and accessible for most cytology laboratories.
RESUMO
Legionnaires' disease is a well recognized cause of community acquired pneumonia (CAP) all around the world. In Latin America its incidence remains unknown. This study analyzed a cohort of 9 patients with CAP due to Legionella pneumophila observed from 1997 to 2001, in the Hospital de Clínicas José de San Martin, University of Buenos Aires. Clinical history included recent illnesses, work exposure, physical exam, prior antibiotic use and severity of illness criteria. None of the 9 patients had a history of recent travels, and 4 of them required admission in intensive care unit (ICU). Seven patients had a cigarette smoking history, four of them also had COPD, and one patient had a non-Hodgkin lymphoma. This study confirms the low specificity of clinical and general laboratory criteria to predict this etiology. Legionella isolation is difficult, and serological testing allows retrospective diagnosis but takes several weeks, while urinary antigen test gives a bed-side diagnosis. When Legionella appears in isolated cases, as happens in Argentina, it should be necessary to have a high index of suspicion to successfully arrive at an etiological diagnosis. Legionella pneumophila is a pathogen causing CAP in our area. A surveillance should be established preferably focused on selected populations including severe CAP, immunocompromised hosts and patients with chronic obstructive pulmonary disease.
La enfermedad de los legionarios es una causa de neumonía adquirida en la comunidad (NAC)reconocida en todo el mundo. En Latinoamérica su incidencia es desconocida. En este estudiose analizó a 9 pacientes con NAC por Legionella pneumophila atendidos entre 1997 y 2001 en el Hospital deClínicas José de San Martín de la Universidad de Buenos Aires. Se registraron datos de antecedentes, enfermedad actual, contactos, exposición laboral, examen físico, pruebas de laboratorio y uso previo de antibióticos, y se tomó en cuenta la presencia de criterios de gravedad. Nueve pacientes presentaron diagnóstico de NAC por Legionella, ninguno refirió antecedentes de viajes recientes; cuatro de ellos debieron ser internados en unidades de cuidado intensivo. Siete pacientes tenían antecedentes de tabaquismo, 4 tenían EPOC y un paciente linfoma no-Hodgkin. Nuestra casuística corrobora la baja especificidad de la clínica y estudios complementarios para predecir esta etiología. El aislamiento de Legionella es dificultoso, la seroconversión permite eldiagnóstico retrospectivo y requiere plazos prolongados y el antígeno urinario aporta un diagnóstico inmediato.Cuando la legionelosis aparece en casos aislados, como ocurriría en Argentina, si no se piensa en esta etiologíano se llegará al diagnóstico. Legionella pneumophila es un patógeno de NAC en nuestro medio, debe buscarsemejor, particularmente en pacientes graves, inmunodeprimidos y en fumadores con enfermedad pulmonarobstructiva crónica (EPOC).