From the Guidelines
Hansen's syndrome, also known as leprosy, is a chronic bacterial disease characterized by the involvement of skin, peripheral nerves, and mucosa of the upper airway, caused by Mycobacterium leprae. According to the case definitions for infectious conditions under public health surveillance by the Centers for Disease Control and Prevention 1, the disease represents a spectrum reflecting the cellular immune response to Mycobacterium leprae. The major forms of the disease have typical characteristics, including:
- A chronic bacterial disease
- Involvement primarily of skin
- Involvement of peripheral nerves
- Involvement of the mucosa of the upper airway The disease develops slowly, with symptoms sometimes taking years to appear after infection, and can be curable with multidrug therapy. Early diagnosis and treatment are crucial to prevent permanent nerve damage and disability, as noted in the study by the Centers for Disease Control and Prevention 1. Despite historical stigma, the disease is not highly contagious and requires prolonged close contact for transmission. Modern antibiotics have made Hansen's syndrome a manageable condition, though it remains a public health concern in some developing regions. The clinical forms of Hansen disease, as described in the study 1, reflect the spectrum of the disease, highlighting the importance of understanding the cellular immune response to Mycobacterium leprae.
From the Research
Definition of Hansen's Syndrome
- Hansen's syndrome, also known as leprosy, is a chronic infectious disease caused by the bacillus Mycobacterium leprae 2.
- It primarily affects the skin and peripheral nerves, leading to nerve damage and the development of disabilities 2.
Clinical Characteristics
- The disease is clinically characterized by one or more of the three cardinal signs: hypopigmented or erythematous skin patches with definite loss of sensation, thickened peripheral nerves, and acid-fast bacilli detected on skin smears or biopsy material 2.
- Leprosy has a number of distinct clinical presentations, including indeterminate leprosy, lepromatous leprosy, tuberculid leprosy, and a borderline form between lepromatous and tuberculoid leprosy 3.
Pathogenesis
- M. leprae primarily infects Schwann cells in the peripheral nerves, leading to nerve damage and the development of disabilities 2.
- The susceptibility to the mycobacteria and the clinical course of the disease are attributed to the host immune response 2.
Diagnosis and Treatment
- Diagnosis is clinical and is made when the patient has at least one of the cardinal signs specified by the World Health Organization 4.
- Leprosy is treated with a multidrug combination of rifampicin, clofazimine, and dapsone, with two main regimens used depending on whether the patient has paucibacillary or multibacillary disease 4.