Cutaneous Leishmaniasis Diagnosed by Press Imprint Smear

Two biopsy samples were taken from the borders of ulcers (lesions) using a 3-mm disposable punch. One biopsy specimen was fixed in 10% formalin and processed for histopathology and the other specimen was used for a Press-Imprint-Smear.

For the imprint, the biopsy sample was put on a glass slide, and another glass slide was used to cover the tissue fragment sandwiched in between. On a firm surface, the tissue fragment between both glass slides was squeezed or squashed. Pressure on the middle of the slides was made, and therefore, the juice and tissue cells were spread on both slides surfaces that were in contact with the sample. Smears were air dried, fixed in methanol, stained with Giemsa, and examined microscopically using a 100 × oil immersion lens.

In 69 (92%) patients, the diagnosis of cutaneous leishmaniasis was confirmed by the identification of amastigotes by one or both methods. In 64 (85.3%) patients, amastigotes were detected by Press-Imprint-Smear. In 33 (44%) patients, amastigotes were detected by histopathology, and in 28 (37.3%) patients, amastigotes were detected by both methods. In 36 (48%) patients, parasites were seen only by Press-Imprint-Smear, and in five (6.7%) patients, parasites were seen only by histopathology. Leishmania (Viannia) braziliensis was the only species in this area.

The authors concluded that the Press-Imprint-Smear method was quicker that the histological method as it only took about an hour and had a much higher sensitivity of 85.3% compared with histology at 44%. Considering its sensitivity, low cost, and simplicity, Press-Imprint-Smear is a valuable tool for diagnosing cutaneous leishmaniasis and potentially, other infectious diseases at the point of care in rural or resource-limited endemic regions. The study was published on August 11, 2014, in the American Journal of Tropical Medicine and Hygiene.

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