ABSTRACT – Leprosy also known as Hansen’s disease, a bacterial infection which damages the skin and peripheral nervous system....
Leprosy is a disease mainly caused by the bacteria Mycobacterium leprae, which causes damage to the skin and the peripheral nervous system. The disease develops slowly (from six months to 40 years) and results in skin lesions and deformities, most often affecting the cooler places on the body (for example, eyes, nose, earlobes, hands, feet, and testicles). The skin lesions and deformities can be very disfiguring and are the reason that historically people considered infected individuals outcasts in many cultures. Although human-to-human transmission is the primary source of infection, three other species can carry and (rarely) transfer M. leprae to humans: chimpanzees, mangabey monkeys, and nine-banded armadillos. The disease is termed a chronic granulomatous disease, similar to tuberculosis, because it produces inflammatory nodules (granulomas) in the skin and peripheral nerves over time.
Leprosy is caused mainly by Mycobacterium leprae, a rod-shaped slow-growing bacillus that is an obligate intracellular (only grows inside of certain human and animal cells) bacterium. M. leprae is termed an “acid fast” bacterium because of its chemical characteristics. When medical professionals use special stains for microscopic analysis, it stains red on a blue background due to mycolic acid content in its cell walls. The Ziehl-Neelsen stain is an example of the special staining techniques used to view the acid-fast organisms under the microscope.
Currently, the organisms cannot be cultured on artificial media. The bacteria take an extremely long time to reproduce inside of cells (about 12-14 days as compared to minutes to hours for most bacteria). The bacteria grow best at 80.9 F-86 F, so cooler areas of the body tend to develop the infection. The bacteria grow very well in the body’s macrophages (a type of immune system cell) and Schwann cells (cells that cover and protect nerve axons). M. leprae is genetically related to M. tuberculosis (the type of bacteria that cause tuberculosis) and other mycobacteria that infect humans. They are leprosy-related diseases. As with malaria, patients with leprosy produce anti-endothelial antibodies (antibodies against the lining tissues of blood vessels), but the role of these antibodies in these diseases is still under investigation.
In 2009, investigators discovered a new Mycobacterium species, M. lepromatosis, which causes diffuse disease (lepromatous leprosy). Considered one of the tropical diseases, this new species (determined by genetic analysis) appeared in patients located in Mexico and the Caribbean islands.
Signs & Symptoms:
Unfortunately, the early signs and symptoms of leprosy are very subtle and occur slowly (usually over years). The symptoms are similar to those that may occur with syphilis, tetanus, and leptospirosis. The following are the major signs and symptoms of leprosy:
Numbness (among the first symptoms)
Loss of temperature sensation (among the first symptoms)
Touch sensation reduced (among the first symptoms)
Pins and needles sensations (among the first symptoms)
Deep pressure sensations are decreased or lost
Blisters and/or rashes
Ulcers, relatively painless
Skin lesions of hypopigmented macules (flat, pale areas of skin that lost color)
Eye damage (dryness, reduced blinking)
Large ulcerations (later symptoms and signs)
Hair loss (for example, loss of eyebrows)
Loss of digits (later symptoms and signs)
Facial disfigurement (for example, loss of nose) (later symptoms and signs)
Erythema nodosum leprosum: tender skin nodules accompanied by other symptoms like fever, joint pain, neuritis, and edema
This long-term developing sequence of events begins and continues on the cooler areas of the body (for example, hands, feet, face, and knees).
Antibiotics treat the majority of cases (mainly clinically diagnosed) of leprosy. The recommended antibiotics, their dosages, and length of time of administration are based on the form or classification of the disease and whether or not the patient is under medical supervision. In general, two antibiotics (dapsone and rifampicin) treat paucibacillary leprosy, while multibacillary leprosy is treated with the same two plus a third antibiotic, clofazimine. Usually, medical professionals administer the antibiotics for at least six to 12 months or more to cure the disease.
Antibiotics can treat paucibacillary leprosy with little or no residual effects on the patient. Multibacillary leprosy can be kept from advancing, and living M. leprae can be essentially eliminated from the person by antibiotics, but the damage done before antibiotics are administered is usually not reversible. Recently, the WHO suggested that single-dose treatment of patients with only one skin lesion with rifampicin, minocycline (Minocin), or ofloxacin (Floxin) is effective. Studies of other antibiotics are ongoing. Each patient, depending on the above criteria, has a schedule for their individual treatment, so a clinician knowledgeable about that patient’s initial diagnostic classification should plan a patient’s treatment schedules. .
Medical professionals have used steroid medications to minimize pain and acute inflammation with leprosy; however, controlled trials showed no significant long-term effects on nerve damage.
The role for surgery in the treatment of leprosy occurs after a patient completes medical treatment (antibiotics) with negative skin smears (no detectable acid-fast bacilli) and is often only needed in advanced cases. Medical professionals individualize surgery for each patient with the goal to attempt cosmetic improvements and, if possible, to restore limb function and some neural functions that were lost to the disease.
Special clinics run by the National Hansen’s Disease Program may treat some people in the United States.
As is the case with many diseases, the lay literature contains home remedies. For example, purported home remedies include a paste made from the neem plant, Hydrocotyle, also known as Cantella asiatica, and even aromatherapy with frankincense. Patients should discuss any home remedies with their physician before using such methods; often there is little or no scientific data to uphold these cure claims.