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Fnac study of histoid nodule: an early tool for diagnosis
1Department of Dermatology & Venereology, VSS Medical College, Burla, Sambalpur 768 017, Orissa.
Insights
Histoid leprosy, a variant of lepromatous leprosy, arises from changes in Mycobacterium leprae growth, potentially due to localized immunity loss. Fine needle aspiration cytology aids early diagnosis of histoid leprosy by identifying characteristic spindle-shaped histiocytes.
Area of Science:
- Dermatology
- Microbiology
- Pathology
Background:
- Leprosy is a chronic infectious disease caused by Mycobacterium leprae.
- Lepromatous leprosy (LL) is the most infectious form, characterized by widespread bacilli.
- Histoid leprosy is a rare variant of LL, presenting distinct clinical and histological features.
Observation:
- Histoid lesions show a unique growth pattern of Mycobacterium leprae.
- This pattern is associated with localized areas of immune deficiency.
- Cellular morphology reveals a characteristic pallisading arrangement of multi-layered, spindle-shaped histiocytes.
Findings:
- Fine needle aspiration cytology (FNAC) can effectively diagnose histoid leprosy.
- FNAC allows for early recognition of the histoid variant.
- Distinguishing histoid leprosy from conventional LL modules is crucial for appropriate management.
Implications:
- FNAC offers a simple and less traumatic diagnostic method compared to biopsies.
- Early diagnosis facilitates timely and targeted treatment strategies.
- Understanding the distinct features of histoid leprosy improves patient outcomes and disease control.
Abstract:
Histoid lesion, a variety of lepromatous leprosy, is due to alteration in the growth pattern of Mycobacterium leprae, possibly due to loss of immunity in localized areas. The distinction is based on cellular morphology by demonstrating pallisading arrangement of multi-layered spindle-shaped histocytes. Cytodiagnosis by fine needle aspiration cytology is therefore an early tool to recognize the histoid variety, differentiating it from a conventional LL module, as it is a simple and less traumatic procedure.
