Scrape cytology in localized oral mucosal leishmaniasis.

Sir,

Leishmaniasis is a protozoan disease and is one of the most common infectious diseases worldwide.[1] The different types of leishmaniasis depending upon the site of involvement are cutaneous, mucocutaneous and visceral leishmaniasis. Leishmania species primarily affect the monocyte-macrophage system. If the histiocytic response to leishmania remains confined to the skin, cutaneous lesions develop, however if dissemination of the protozoan occurs; internal organs become involved. Mucosal involvement is, usually, associated with cutaneous involvement. Exclusive involvement of the mucosal surface is rare. We report a case of mucosal leishmaniasis (ML) diagnosed on scrape cytology.

A 67-year-old male presented to the dermatology OPD with complain of pain in the mouth for the past 1½ year, which had increased in the past 3 days so much so that the patient had difficulty in chewing food. On examination, multiple ulcerative lesions were found in the oral mucosa on the hard palate, tongue, retro molar trigone and tonsillar area [Figure 1]. There was the presence of a single submandibular lymph node measuring 0.5 cm in diameter. FNAC of the lymph node was performed, and the smear revealed a polymorphous population of lymphoid cells comprising of small mature lymphocytes, centrocytes, centroblasts, a few plasma cells along with tingible body macrophages. A diagnosis of reactive lymph node was made. Scrape smears from the oral lesions were made showing many mature squamous cells, neutrophils, plasma cells, histiocytes and bacterial flora along with the presence of numerous intracellular and extracellular Leishmania donovani bodies [Figure 2]. A diagnosis of ML was made. The patient was re-evaluated and on examination, no skin lesion or hepatosplenomegaly was present. HIV status of the patient was negative. He gave no history of prior skin lesion, weakness, fever, chronic illness or travel outside India. To confirm the diagnosis, rK39 antigen test was done and was found to be positive. Patient was started on amphotericin B and developed severe hypokalemia and succumbed to the complication.

Figure 1

Clinical photograph of the patient showing extensive ulceration and erythema of the oral mucosa

Figure 2

Scrape smear showing intracellular and extracellular Leishmania donovani bodies. (Giemsa ×1000)

The most common types of leishmaniasis found in India are localized cutaneous leishmaniasis, visceral leishmaniasis and post kala azar dermal leishmaniasis. Mucocutanous leishmaniasis (MCL) is found in countries such as Brazil, Venezuela, Peru, Ecuador and Columbia. It is caused by Leishmania b. braziliensis, species not reported in India (where species L. donovani and Leishmania tropica are prevalent).

Mucocutanous leishmaniasis most commonly affects the upper respiratory tract. It, usually, develops subsequent to healed localized cutaneous leishmaniasis by lymphatic or hematogenous dissemination or by direct extension of nearby skin lesions. Oral mucosa involvement is uncommon. Motta et al.[2] studied 11 cases of MCL with oral lesions.

Mucocutanous leishmaniasis is more common in immunocompromised patients. Localized oral mucositis due to leishmania infection is uncommon and has been reported in an HIV positive patient previously.[3] The present case is rare since isolated localized oral ML was seen in an immunocompetent patient. To the best of our knowledge, this has been reported only once before in past literature.[4]

Daneshbod et al.[5] studied cytological and histological features of ML in 11 patients and found cytology to be more reliable than histopathology in making a diagnosis. The present case highlights the use of cytology as an easy, cost-effective and rapid method to diagnose ML.