Hansen’s disease or leprosy is a chronic infectious disease caused by Mycobacterium leprae- intracellular, obligate parasite. Untreated Leprosy affected person(human beings) is the only known source, transmitted to a susceptible person through droplets, mainly via respiratory tract. It principally affecting the cooler parts of the body, mainly skin and peripheral nerves; it also involves muscles, eyes, bones, testis and internal organs. Tuberculoid leprosy indicates a high cellular immune response (i.e., T cells and macrophage activation) and few bacilli in tissues; at the opposite pole, lepromatous leprosy indicates an absent cellular immune response to M. leprae antigens, with no macrophage activation and abundant bacilli in tissues. The spectrum of leprosy is a continuum, and patients may move in either direction according to host response and treatment. The standard delineation follows that of Ridley and Jopling, with categories defined along the spectrum by a combination of clinical, microbiological, histopathological, and immunologic indices: TT (tuberculoid), BT (borderline tuberculoid), MB (mid borderline), BL (borderline lepromatous), and LL (lepromatous). The term borderline is used to denote patterns that share some features of both tuberculoid and lepromatous leprosy.

Table 1: Ridley Jopling Classification of leprosy

Today, access to information, diagnosis and treatment with Multi Drug Therapy(MDT) remain key elements in the strategy to eliminate the disease. The National Leprosy Eradication Programme(NLEP) was launched in 1983 with the objective of arresting the disease activity in all known cases of leprosy. Since the disease has a long incubation period it needs a longer period of surveillance.

OBJECTIVE

1) To find out prevalence of leprosy in our institute.

2) To study the histopathological features of clinically suspected cases of leprosy in skin biopsies and categorise from tuberculoid to lepromatous leprosy based on microscopy.

3) To study Fite Faraco stained sections of all diagnosed cases of leprosy to look for positivity.

4) To determine the nature of various leprosy lesions and to ascertain the frequency and distribution of leprosy lesions.

MATERIALS AND METHODS

Histopathological examination was carried out in Histopathology laboratory of Department of Pathology, PDU Government Medical College and Hospital, Rajkot between the August 2024 to June 2025 time period. Skin biopsies for the study were obtained by incisional or punch biopsy which was performed by the Dermatologist. These biopsies were kept in 10% formalin and sent for histopathological examination along with properly filled requisition form, including detailed clinical history, examination findings indicating signs and symptoms of the skin lesions and provisional clinical diagnosis. Following adequate fixation for about 8-12 hours the tissues were submitted into for routine processing, following which the paraffin embedded serial sections of 4-5 microns thickness were obtained, which were stained with Hematoxylin and Eosin for morphological assessment and Wade Fite staining for identifying the bacilli. The procedure followed for Fite Faraco Stain was Wade-Fite method for M. leprae in paraffin section.

 sections were observed under oil immersion using ×100 objectives. The bacillary index (BI) was assessed in exactly the same way as the one follow for smear. The entire dermis was observed to assess the logarithmic index bacilli.

RESULTS:

Patient Demographics:

A total of 70 cases of leprosy for histopathological evaluation with its clinical correlation and demonstration of lepra bacilli on F. F. stain were included in the study. In present study, age of the patient ranged from 0-80 years.(TABLE-2) Maximum number of cases 41(58.56%) were seen in the age group 21-40 years followed by 17(24.23%) in 41-60 years.

TABLE 2: Distribution of leprosy cases in different Age group:

In present study consisting of 70 cases, 42(60%) were males and 28(40%)were females. Male to female ratio was 3:2 (TABLE- 3)

TABLE 3: Distribution of leprosy cases according to gender

In present study (Table 4)the maximum number of cases 33(47.2%) cases were of lepromatous leprosy followed by 11(15.77%) cases of Borderline Tuberculoid leprosy, 10(14.3%) cases of Borderline Lepromatous , 08(11.44%) cases of Lepromatous leprosy with Erythma Nodosum Leprosum, 05(7.14%) cases of Tuberculoid leprosy, 03(4.29%) cases of Mid Borderline leprosy seen.

TABLE 4: Distribution of various types of leprosy by histopathological examination

(TT- Tuberculoid leprosy, BT- Borderline Tuberculoid leprosy, MB- Mid Borderline leprosy, BL- Borderline Lepromatous leprosy, LL- Lepromatous Leprosy, LL with ENL- Lepromatous Leprosy with Erythema Nodosum Leprosum)

TABLE 5:Distribution of clinical features in various types of leprosy

Out of 70 cases of skin biopsies it can be observed(Table 5) that Tingling and numbness seen in 36 cases(51.44%)which was the most common clinical feature, Hypopigmented lesions and Erythematous lesions seen in 22 cases(31.44%)were 2^nd most common feature observed followed by Nerve thickening seen in 11 cases(15.77%), Nodules seen in 10 cases(14.23%) and anesthesia(loss of sensation) seen in 07 cases(10%).

TABLE 6: Correlation of clinical and histopathological classification in leprosy cases

(TT- Tuberculoid leprosy, BT- Borderline Tuberculoid leprosy, MB- Mid Borderline leprosy, BL- Borderline Lepromatous leprosy, LL- Lepromatous Leprosy, LL with ENL- Lepromatous Leprosy with Erythema Nodosum Leprosum)

From Table 6 it can be observed that the overall concordance between clinical and histopathological classification was   72.32%. Maximum concordance was seen in Borderline lepromatous leprosy which was 100% followed by 75% in BT, 75% MB, 76.74% in LL, 71.42% in TT.

TABLE 7: Percentage distribution of F F Stain positivity among various histologic types of leprosy

(TT- Tuberculoid leprosy, BT- Borderline Tuberculoid leprosy, MB- Mid Borderline leprosy, BL- Borderline Lepromatous leprosy, LL- Lepromatous Leprosy, LL with ENL- Lepromatous Leprosy with Erythema Nodosum Leprosum)

From above table 7 it can be said that out of 70 cases which were diagnosed by Histopathological examination into different form of leprosy , 62 cases (88.57%)were F. F. Positive. Out of these positive cases, maximum cases of LL were found. Low positivity was seen in BT and MB.

Bacillary index was highest in HL, LL and BL having grade 5+, 6+ while it was lower in other types of leprosy ranging from 1+ to 4+

DISCUSSION

The present study demonstrated the clinico-histopathological examination of total 70 cases of leprosy of August 2024 to July 2025(11 months) was carried out in the Department of Pathology, P.D.U. Government Medical College & Hospital, Rajkot. Accurate diagnosis is of fundamental importance to all aspects of leprosy epidemiology, management and prevention of disability. Under diagnosis will lead to continued transmission of disease and much needless sufferings. The attitude of society, methods of case detection, type of personnel carrying out survey, method and frequency of examination, the criteria adopted for diagnosis, type of classification of disease, are some variables that affect the description of the condition. Histopathological examination continues to be an important tool in accurate diagnosis and classification of leprosy and still remains the gold standard.

Table 8: Comparison of gender distribution in leprosy cases with various study

From above table-8 it can be observed that male preponderance observed in present study(60%) is comparable to all other studies which reported M:F ratio from 1.5, 1.4, 1.1, 1.8.

Table 9: Comparison of spectrum of leprosy of present study with various study

(TT- Tuberculoid leprosy, BT- Borderline Tuberculoid leprosy, MB- Mid Borderline leprosy, BL- Borderline Lepromatous leprosy, LL- Lepromatous Leprosy, LL with ENL- Lepromatous Leprosy with Erythema Nodosum Leprosum)

From above table-9 it is observed that In present study most common type of leprosy was the lepromatous leprosy , 33 cases(47.2%) followed by borderline tuberculoid leprosy is comparable to all other studies which suggest that no. Of infective cases (LL) are more common in Gujarat state as in present study.

Table 10: Comprison of clinicopathological correlation

(TT- Tuberculoid leprosy, BT- Borderline Tuberculoid leprosy, MB- Mid Borderline leprosy, BL- Borderline Lepromatous leprosy, LL- Lepromatous Leprosy, HL- Histoid Leprosy)

Different studies showed variable clinicopathological correlation. In present study, maximum clinicopathological correlation seen in cases of Borderline Lepromatous leprosy (100%) while in Sindhushree et al study maximum correlation seen in Histoid leprosy (57.14%) and in Kalla et al maximum clinicopathological seen in cases of TT (76.70%).^21,22

Out of 70 patient, which were diagnosed by Histopathological examination into different forms of leprosy, Modified fite faraco stain positivity was in 88.57% was somewhat higher to the study of Deepa sowkur Anandarma aligra and Surekha B Hippargi 2 in 2016. It may be due to more cases of LL in present study.

CONCLUSION

Leprosy is one of the leading causes of physical disabilities which contribute to intense social stigma resulting in discrimination of patients and their families,especially in low-economic communities.The clinical manifestations of leprosy are so diverse and can mimic a variety of unrelated diseases. Presentation may vary from an insignificant skin lesion to extensive disease. Lack of accurate diagnosis and treatment of leprosy can cause permanent damage to skin, nerves, limbs and eyes leading to deformities.

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