The Importance of the Biopsy Technique in the Diagnosis of Histoid Leprosy

Abstract

Histoid leprosy (HL) was originally described by Wade in 1963 and is regarded as a rare variant of lepromatous leprosy (LL). These characteristic clinical lesions are firm, deeply adhered nodules with features reminiscent of dermatofibromas or keloids in a background of apparently healthy skin. The main histopathological findings described are the presence of spindle cell histiocytes immersed in a richly collagenized background, usually forming a nodular pattern of infiltration with sharply delimitation and positive staining for acid-fast bacilli. The classical form of HL lesions should be devoid of foam histiocytes and globi. However, we and other authors noticed that in most of the cases, despite characteristic clinical features, histopathology depicts a mixture of LL and HL patterns. Therefore, we present a case with clinical features similar to HL in which an excisional scalpel biopsy of a nodule demonstrated features of classical LL in the center of the lesion and features of HL in the periphery, highlighting that a proper biopsy technique could enhance the ability of the dermatopathologist to histopathologically diagnose cases of HL. In cases in which HL is clinically suspected, we advocate replacing the usual 4-mm incisional punch biopsy by a broader elliptical scalpel biopsy, encompassing the totality of the lesion whenever possible to achieve a reliable representation of the pathologic process.

Challenges related to the cases of lepromatous leprosy: a report of two cases

“…Overall, the epidermis layer covering the skin lesions is atrophied. According to the latest report, histopathological investigations could demonstrate the conventional lepromatous leprosy in the center of the lesions [ 9 ]. A skin biopsy of our patients has confirmed the diagnosis.…”

Multiple Dermatofibroma-Like Lesions in a 37-Year-Old Man: Answer

“…The mycobacteria characteristically arrange in parallel bundles following the long axis of the spindle histiocytic cells, which has been described as "histoid habitus". 7 Fineneedle aspiration cytology, and the recognition of this cytomorphological features, has been proved to be useful in establishing a rapid diagnosis in some cases. 9 The pathogenicity of HL is still not clear, but the histoid lesions seem to result from a combination of low host immune response, and the development of drug resistant bacilli, especially after antibiotic monotherapy or incomplete multidrug therapy.…”

“…Specific acid-fast bacilli stain (Wade–Fite) will confirm the presence of large numbers of bacilli within the macrophages, known as globi. 7,8…”

“…The mycobacteria characteristically arrange in parallel bundles following the long axis of the spindle histiocytic cells, which has been described as “histoid habitus”. 7 Fine-needle aspiration cytology, and the recognition of this cytomorphological features, has been proved to be useful in establishing a rapid diagnosis in some cases. 9…”

A Case Report of Prurigo Nodularis-Like Lesions in a Patient with Lepromatous Leprosy

“…The epidermis overlying the lesion is generally atrophied. A recent study reported that histopathological examinations could reveal classical LL in the center but with features of HL in the periphery of the lesions [11]. The authors of that study recommended performing an elliptical scalpel biopsy for making a reliable diagnosis.…”