What are the symptoms of leprosy (Hansen disease)?

Leprosy Symptoms

Leprosy (Hansen disease) presents with characteristic skin lesions that are hypopigmented or erythematous with definite sensory loss, thickened peripheral nerves, and involvement of the upper respiratory mucosa, with clinical manifestations varying along a spectrum based on the host's cellular immune response to Mycobacterium leprae. 1, 2

Primary Clinical Features

The disease manifests through three cardinal signs that define clinical diagnosis:

• Hypopigmented or erythematous skin lesions with definite loss of sensation 1, 3, 4
• Thickened peripheral nerves that can be palpated on examination 1, 3, 4
• Upper respiratory mucosa involvement leading to nasal symptoms 1, 5

Clinical Spectrum Based on Immune Response

The presentation varies dramatically depending on the patient's cellular immune response, creating distinct clinical forms:

Tuberculoid (Paucibacillary) Form

• One or a few well-demarcated, hypopigmented, and anesthetic skin lesions 1, 2, 5
• Active, spreading edges with clearing centers 1, 2
• Peripheral nerve swelling or thickening may occur 1, 5
• Represents strong cell-mediated immunity 2

Lepromatous (Multibacillary) Form

• Multiple erythematous papules and nodules in bilateral and symmetrical distribution 1, 2, 6
• Infiltration of the face, hands, and feet that progresses to skin thickening 1, 2, 6
• Nodules (lepromas) that may ulcerate 6
• Progressive skin thickening with loss of normal skin architecture 6
• Represents weak cell-mediated immunity 2

Borderline (Dimorphous) Form

• Skin lesions characteristic of both tuberculoid and lepromatous forms 1

Indeterminate Form

• Early lesions, usually hypopigmented macules 1
• Without developed tuberculoid or lepromatous features 1

Neurological Manifestations

• Peripheral neuropathy with weakness of affected body parts 7
• Numbness in affected areas 8
• Inflammation and tenderness of peripheral nerves 7
• Anesthesia in skin lesions is pathognomonic for leprosy 6

Ocular Involvement

• Eye pain 8
• Loss of vision 8
• Nasolacrimal duct obstruction can occur as a late complication 9

Common Pitfalls in Recognition

The key distinguishing feature is sensory loss in skin lesions, which is pathognomonic for leprosy and absent in most mimicking conditions. 6 Failure to test for sensory loss can lead to missed diagnosis, as many other granulomatous diseases produce similar-appearing skin lesions but without anesthesia.

The bilateral and symmetrical distribution of lesions in lepromatous leprosy strongly suggests the diagnosis and helps differentiate it from tuberculoid leprosy, which presents with asymmetric, few lesions. 6

Leprosy should be suspected in patients with skin lesions and peripheral neuropathy, particularly those from endemic regions or with exposure to nine-banded armadillos. 7, 8, 10