Histopathological Correlation in Different Types of Leprosy in a Tertiary Health Care Centre

Abstract

Hansen’s disease or Leprosy, is a chronic infectious disease that is contagious and has a slow evolution. It affects mainly skin and schwann cells in the peripheral nerves and causes peripheral neuropathy which contributes to the permanent functional impairments [1]. It is caused by a rod shaped,acid fast staining bacteria known as Mycobacterium Leprae which has parallel sides, round ends and a characteristic bundle of cigar appearance due to the presence of a glial substance which is a surface lipid that makes the bacilli to be arranged side by side in parallel arrays [2]. It has a distinctive empathy towards the peripheral nerves where it establishes originally therefore it is the site where the pathological processes start mainly with the principal target being Schwann cell [3,4].  Amidst the communicable diseases, Leprosy is the most common cause of physical disabilities which is permanent. When the bacterium enters a person with good cell-mediated immunity against it, it gets destroyed. If there is a slight impairment in the cell-mediated immunity against it, some bacilli will multiply and a lesion develops. Depending upon the immune status of a host, it expresses itself in different clinico-histopathological forms [5]. Ridley and Jopling suggested a five-group classification of leprosy known as immunological classification based upon the immunological status of the patient as (a) tuberculoid (TT), (b) borderline tuberculoid (BT), (c) mid-borderline (BB), (d) borderline lepromatous (BL) and (e) lepromatous (LL) [6]. Bacteriological, immunological, clinical and histopathological features exhibit continuous but slow changes from one pole to another pole. The main disadvantage of this classification is that there is no specific position for pure neuritic as well as indeterminate leprosy in the spectrum [7].