A new scenario in the immunohistochemical diagnosis of cutaneous leishmaniasis

Abstract

Cutaneous lesions of leishmaniasis are easy to diagnose when clinically obvious or when amastigotes are numerous in the biopsy. However, this is not always the case. In difficult cases, the diagnosis of leishmaniasis requires a reliable tool to identify the microorganisms. The identification of the parasite via microscope has a superior sensitivity to that of culture, and molecular techniques, such as polymerase chain reaction (PCR), highly improve the sensitivity of the diagnosis. Alternatively, immunohistochemistry has emerged as an affordable alternative to PCR. Several laboratories have produced their own antibodies against Leishmania and seem satisfied with the results. Nevertheless, most of these antibodies are not commercialized or standardized. Pathology also welcomed the unexpected positivity of amastigotes with certain clones of anti-CD1a. The latter does not universally stain all species of Leishmania, with a low sensitivity for New World species. In conclusion, although anti-CD1a is a reliable complementary tool in the diagnosis of leishmaniasis, pathologists should familiarize themselves with one of the specific antibodies against Leishmania and globalize its use, standardizing and adapting the technique.

Histopathology of Cutaneous Leishmaniasis Caused by Leishmania donovani in Sri Lanka

“…While the inclusion of molecular techniques such as PCR has greatly improved the sensitivity of diagnosis, they are costly and not readily available. Immunohistochemistry is emerging as a new tool in the identification of the Leishmania organism, with studies showing that Cd1a immunostaining is useful in the detection of Leishmania organisms [22][23][24][25]. This has not been assessed in L. donovani species and may prove to be a useful adjunctive test in equivocal cases and cases of visceral leishmaniasis.…”

Cocaine-Induced Plasma Cell Orificial “Dermatomucositis”: A More Accurate Descriptive Term for a Clearly Dermatological Entity

“…Immunohistochemistry with certain anti-CD1a antibodies can highlight microorganisms of some Leishmania species, but not all. 33,34 In our experience, CD1a staining is useful for confirming the presence of Leishmania already identified with Hematoxylin and Eosin staining, but it may be less effective in detecting Leishmania when present in small quantities. In this regard, anti-Leishmania antibodies have been developed, showing promising results.…”

Suspicious Skin Lesion in an 11-Year-Old Male

“…5 Recent literature reports high sensitivity of polymerase chain reaction (PCR) testing for diagnosis of LCL, particularly when used in combination with conventional methods. 4,[6][7] The differential diagnosis also included infection secondary to Staphylococcus spp., Mycobacterium spp., and fungi (eg Sporothrix or Blastomyces spp.). Tissue cultures ultimately indicated clindamycin resistant, methicillin sensitive Staphylococcus aureus (MSSA).…”