Appropriately Selected Nerve in Suspected Leprous Neuropathy Yields High Positive Results for Mycobacterium leprae DNA by Polymerase Chain Reaction Method

Abstract

Identification of Mycobacterium leprae DNA by polymerase chain reaction (PCR) is a reliable and an affordable method to confirm leprosy. DNA from 87 nerve samples (61 from paraffin blocks and 26 fresh samples) was extracted. Mycobacterium leprae DNA was amplified by PCR from 80/87 (92%) specimens. Patients were seen over a period of 11 years (2007)(2008)(2009)(2010)(2011)(2012)(2013)(2014)(2015)(2016)(2017)(2018)(2019), and leprosy was diagnosed based on clinical and characteristic histopathology findings. The clinical diagnostic possibilities were as follows: leprous neuropathy in 73/80 (91.3%), mononeuritis multiplex of unknown etiology in four (5.0%), vasculitic neuropathy in two (2.5%), and distal symmetric sensory motor neuropathy in one (1.3%). The biopsied nerves were as follows: superficial radial = 34 (42.6%), dorsal cutaneous branch of ulnar = 19 (23.8%), sural = 18 (22.5%), and superficial peroneal = 9 (11.3%), and corresponding neurological deficits were recorded in 77 (96.3%) cases. The histopathological diagnoses in total group were as follows: (borderline tuberculoid (BT) = 52, tuberculoid (TT) = 8, borderline lepromatous (BL) = 8, borderline borderline (BB) = 3, nonspecific inflammation = 3, healed/ fibrosed = 4, and axonopathy = 2). Acid fast bacilli (AFB) was demonstrated in 11 (13.7%) samples. For comparison, 31 clinically and histopathologically defined non-leprous disease control nerves (inherited neuropathy = 20, vasculitis = 8, and nutritional neuropathy = 3) subjected to PCR were negative for M. leprae DNA. In most instances, there are multiple thickened peripheral nerves in suspected cases of leprosy, but neurological deficits pertaining to the thickened nerve are not as widespread. The current findings emphasize the importance of selecting the most appropriate nerve for biopsy to obtain a positive PCR result. We infer that clinical, histopathological, and PCR tests complement each other to help achieve a definitive diagnosis of leprosy particularly in pure neuritic leprosy and in leprous neuropathy with negative skin smears/biopsy.

Hansen’s Disease with Pure Nerve Involvement and Perineural Abscess Mistaken for Peripheral Nerve Sheath Tumour

“…Its causative organism is Mycobacterium leprae. [1][2][3][4][5][6][7][8][9][10][11] There is skin involvement in the form of hypopigmented patches and loss of sensation over the affected areas, which commonly include the skin, peripheral nerves, mucosa of the upper respiratory tract, and eyes. 2,[4][5][6][7][8][9][11][12][13] It also involves the peripheral nervous system, mostly in the form of nerve thickening.…”

“…[1][2][3][4][5][6][7][8][9][10][11] There is skin involvement in the form of hypopigmented patches and loss of sensation over the affected areas, which commonly include the skin, peripheral nerves, mucosa of the upper respiratory tract, and eyes. 2,[4][5][6][7][8][9][11][12][13] It also involves the peripheral nervous system, mostly in the form of nerve thickening. [2][3][4][5][6][8][9][10][11][12][13][14][15] The eyes and testes are highly susceptible to the disease, as they have a lower temperature than the core body temperature.…”

“…2,[4][5][6][7][8][9][11][12][13] It also involves the peripheral nervous system, mostly in the form of nerve thickening. [2][3][4][5][6][8][9][10][11][12][13][14][15] The eyes and testes are highly susceptible to the disease, as they have a lower temperature than the core body temperature. 3,4,16 The ability of the organism to invade the nerve sheath and cause immunemediated reactions gives rise to devitalisation and mutilation promoting coherent psychosocial disruption.…”

Avaliação do comprometimento funcional e manifestações neurológicas em pacientes portadores de Hanseníase em um serviço de referência em Dermatologia no estado do Espírito Santo (ES)

“…Mais de 81% dos novos casos são notificados em três países (Índia, Brasil, e Indonésia) e, em todo o mundo, mais de três milhões de pessoas vivem com deficiência devido à doença. 9 A evolução da neuropatia geralmente é lenta porém com grande potencial de causar incapacidades físicas, refletindo em limitações no trabalho, na vida social e problemas psicológicos. 3 Dermatologicamente, a doença se mostra polimórfica, podendo manifestar manchas hipocrômicas, placas dimórficas, áreas infiltradas, tubérculos ou nódulos, acompanhadas por diminuição ou ausência de sensibilidade.…”