European Journal of Cardiovascular Medicine

Leprosy or Hansen disease is a slowly progressive infection caused by Mycobacterium leprae that mainly involves skin, peripheral nervous system, upper respiratory tract, eyes and testes. Leprosy has been a misdiagnosed, stigmatized and confused condition since biblical times. It is likely that many cases who were excluded from society in all ages of mankind actually suffered from some other skin disease. Following Norwegian Gerhard Hansen and Neisser in Breslau describing the bacterium, many advances in the field of diagnosis and treatment of leprosy were done. Leprosy has an extremely slow course spanning decades most patients die with leprosy than from it. According to World Health Organization (WHO), leprosy is still present in more than 120 countries and is a neglected tropical disease (NTD), with more than 2,00,000 new cases being reported annually. The propensity of disease when untreated to result in characteristic deformity makes early diagnosis, categorization to types and treatment important. So that, the patient can lead productive lives in community as well as deformities and visible manifestations can be largely reduced. Leprosy is one of the oldest debilitating diseases, still there are no tools to diagnose subclinical infections and to culture the bacteria.

Analysis of epidemiological data, clinical features and histopathological features and their interpretation plays a very crucial role in early diagnosis, treatment, disability prevention and most importantly elimination of social stigma in society pertaining to disease. Ridley-Jopling classification which was initially considered as classification for research purpose in now being used widely even in clinical practice. Along with five types of leprosy classified under Ridley-Jopling classification differentiation of Indeterminate leprosy, histoid leprosy and reactions associated with leprosy and its treatment are also important.

Epidemiology of Leprosy:

 Definition of leprosy: A person having one or more of the following features, and who is yet to complete the full course of treatment:

1. Hypopigmented or reddish skin lesion(s) with definite loss of sensation,
2. Nerve thickening with sensory impairment and skin smear positive for acid fast bacilli.

So, any change in the treatment of leprosy will change the epidemiology of the disease. It also defines that if once an individual patient has successfully completed the course of treatment, then the individual is no longer considered as a case.

Mycobacterium leprae, is the causative agent of leprosy. It is an obligate intracellular pathogen that mainly infects macrophages and Schwann cells.

Leprosy is more commonly seen in the age group between 20 and 30 years and in males with male to female ratio as 2:1, but can occur at any age. In endemic regions, childhood is when most of leprosy infections occur. The prevalence of active disease transmission in the community is shown by the rising percentage of childhood leprosy cases in the population. Lepromatous patient’s age distribution often demonstrates that the disease manifests itself later in life than nonlepromatous pole instances.

Ridely- Jopling classification is referred to as immunological classification it is based on the fact that bacteriological, immunological, histopathological and clinical features are interwoven. Under this classification leprosy is classified as a) Tuberculoid Leprosy (TT), b) Borderline Tuberculoid Leprosy (BT) c) Mid borderline (BB) d) Borderline Lepromatous (BL) e) Lepromatous Leprosy (LL).

It is a Descriptive study, done over a period of 3 years (1 year retrospective and 2years prospective study) between July 2019 to June 2022. The skin biopsies of cases clinically diagnosed or suspected of Hansen’s disease submitted to the Department of Pathology, Karnataka Institute of Medical sciences, Hubballi, were studied. The clinical data of retrospective cases were retrieved from departmental records, tissue blocks and slides. During the prospective study period, clinical history, physical examination were noted. Skin biopsies for study were obtained either by punch biopsy or incisional biopsy which will be performed by Dermatologist and submitted to Pathology department. In the present study, various clinical and histopathological factors of leprosy were studied under a spectrum of 9 types of leprosy that is Tuberculoid Leprosy (TT), Borderline Tuberculoid Leprosy (BT), Mid borderline (BB), Borderline Lepromatous (BL) and Lepromatous Leprosy (LL) as suggested by Ridley-Jopling classification along with additional types that is Indeterminate Leprosy (IL), Histoid Leprosy (HL) and reactional leprosy which included type 1 lepra reaction (T1) and type 2 lepra reaction (T2). Results were subjected to appropriate statistical analysis. Descriptive analysis was done in the form of percentage or proportions. MS Excel and MS Word was used to get various types of graphs like bar diagram, Pie diagram. MS Excel, graph pad software by dotmatics (San Diego, California), SPSS version 22 (IBM SPSS Statistics, Somers NY, USA) was used to analyse data. A total of 284 skin biopsies of leprosy cases were received in the Department of Pathology, KIMS Hubballi during the period of 3years (July 2019 to June 2022).

During this study period a total of 1208 skin biopsies were received in our department from the Department of Dermatology, Karnataka Institute of Medical Sciences, Hubballi. Out of these 1208 cases a total of 356 skin biopsies were taken from the patients who were clinically diagnosed or suspected of having Hansen's disease. Out of these 356 cases, 17 cases were excluded from the present study for not revealing sufficient histological features of leprosy or for the reason of samples not being taken from a representative area and 55 cases were excluded after being his pathologically diagnosed with conditions other than leprosy. Finally, 284 cases were included in the present study.

In the present study age of the patients with leprosy ranged from 4 year to 78 years. Youngest patient being 4 years old and eldest being 78 years old, with mean age of 38.52 years. Majority of patients, that is 72 (25.4%) cases were in age interval of 31-40 years, followed by 56 (19.7%) cases, 49 (17.3%) cases, 35 (12.3%) cases, 32 (11.2%) cases, 26 (9.2%) cases in age intervals of 21-30 years, 41-50 years, 51- 60 years, 11-20 years, 61- 70 years respectively in decreasing order of incidenceas shown in table 1. Least incidence of leprosy was observed in the age group of 1- 10 years and 71- 80 years with 9 (3.1%) cases and 5 (1.8%) cases respectively as shown in table 1. In our study it was observed that 20 (7.1%) cases were below the age group of 15 years and remaining 264 cases (92.9%) cases above it.

Table 1: Showing age distribution of leprosy cases in the present study.

In the present study, male predominance was observed with male to female ratio of 1.9:1. There were 185 (65.14%) cases as males and remaining 99 (34.85%) cases as female, as shown in table 2.

Table 2: Sex wise distribution of leprosy cases in the present study.

Type of skin lesions of leprosy cases in the present study:

The most common clinical presentation of leprosy in the present study was patch which was seen in 157 (55.2%) cases. In the present study most common colour of skin lesion observed was hypopigmentation accounting to 152 (53.5%) cases, followed by erythema in 117 (41.1%) cases and xerosis in 15 (5.2%) cases. In the present study 64 (22.5%) cases out of 284 cases showed peripheral nerve thickening. Out of these 64 cases, 49 cases showed symmetrical nerve thickening and remaining 15 cases presented with asymmetrical nerve thickening. Among thickened nerves ulnar nerve was the most common nerve involved followed by radial cutaneous nerve.

Histological classification of Leprosy in the present study:

In the present study (following histologically confirmation) Borderline Tuberculoid Leprosy (BT) was the most common subclass of leprosy encountered, accounting for 130 (45.7%) cases which was followed by Indeterminate Leprosy (IL) in 42 (14.8%) cases, Tuberculoid Leprosy (TT) and Borderline Lepromatous (BL) were almost equal that is 24 (8.45%) and 23 (8.09%) cases respectively. Cases of Lepromatous Leprosy (LL) were 19 (6.7%), type 2 lepra reaction (T2) were 17 (5.98%) and Mid borderline (BB) were 11 (3.85%) while Histoid Leprosy (HL) and type 1 lepra reaction (T1) showed similar incidence of 9 (3.17%) cases each as shown in table 3.

Table 3: Showing frequency of different types of leprosy in the present study.

In the present study, various clinical and histopathological factors of leprosy were studied under a spectrum of 9 types of leprosy that is TT, BT, BB, BL and LL as suggested by Ridley-Jopling classification along with additional types that is IL, HL and reactional leprosy which includedT1 and T2 lepra reactions.

In the present study, the spectrum of age of patients having leprosy ranged from 4 years to 78 years with mean age of 38.52 years, which was similar to that of studies done by Kumar SA et al. (2017) and Kumar A et al. (2014) with mean age of 34.6 years and 40.1 years respectively. The male predominance was observed with 185 (65.14%) cases as males and remaining 99 (34.85%) cases as female. Male to female ratio was 1.9:1. These findings were similar to observations done by Soni et al. (2019), Tiwari M et al. (2019) and Nadia et al.64 (2015). In the present study the most common type of skin lesion in leprosy was patch accounting to 147 (51.7%) cases, similar to study done by Nadia et al.64 (2015) but studies done by Kumar SA et al. (2017) and Soni et al. (2019) showed plaque and macule as most common skin lesions respectively. Hypopigmentation accounting for 152 (53.5%) cases, similar to findings in study done by Nadia et al. (2015) and Soni et al. (2019)

In present study 64 (22.5%) cases out of 284 cases showed peripheral nerve thickening. While study done by Yadav N et al. (2019) had 28 (45.1%) cases with involvement of peripheral nerves. But the sample size of Yadav N et al. (2019) was small that is 62 cases. In our study among thickened nerves ulnar nerve was the most common nerve involved accounting to 12 (18%) cases similar to study done by M. I. Celine et al. (2021) and Yadav N et al. (2019) who had 32 (91.4%) cases and 16 (25.8%) with ulnar nerve thickening respectively.

In the present study the incidence of BT was most common subclass of leprosy both clinically and histopathologically. Out of 284 cases of histologically proven leprosy cases, 130 (45.7%) cases were BT cases. This finding was similar to the observations done by, Banushree CS et al. (2016) But there was disagreement for this in studies done by Yadav N et al. (2019) and Valand et al. (2017) in which IL and TT were more common type of leprosy respectively.

Leprosy is a chronic infectious disease caused by Mycobacterium leprae. It is a curable disease, but, with lots of misconception and superstition attached to it. Diagnosis and treatment in the early stages of leprosy can prevent disability in patients.

We observed in the present study thatthe people who were in age group of 31- 40 years, especially males were affected more by the disease, in most of the instances theybeing the sole bread earners ofthe family, this would directly or indirectly hamper the social and economic status of the family.

This calls for a need in enhancing awareness among people regarding the disease and accelerating active surveillance in the community.

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