Leprosy is characterized as a chronic infectious disease that may cause severe and disfiguring skin sores and neuropathy to the extremities. Because this disease is shrouded in terrifying stigmata in ancient times, lepers are often times out casted from the society. Any outbreaks of leprosy in any country are now met with substantial panic due to this negative stigmata in our past.
Presentation
The main symptomatology in leprosy are the cutaneous pale sores and lumps which typically persist from weeks to months. In the same way, significant nerve damage leads to peripheral neuropathy that may lead to paresthesia or loss of sensation in arms and legs. Bacillary invasion of the eyes may occur and cause corneal ulcerations and iridocyclitis of the affected eyes [8]. There will also be a consequent paralysis presenting as muscle weakness in the extremities. The symptoms will surface usually after 3 to 5 years from initial contact with an infected carrier.
Workup
The characteristic cutaneous lesions with history of exposure to an infected person may give the primary physician a clue that he is dealing with a leprosy case. To further confirm the diagnosis, the following diagnostic modalities and tests may be performed to patients presenting with signs and symptoms of leprosy:
- Skin biopsy or slit skin test will demonstrate the actual bacteria after an acid fast staining technique is applied overt the sample skin tissues under microscopy [9].
- Skin scrapings examination in which the surface of the cutaneous lesions are scraped using a scalpel and stained with acid fast demonstrate the Mycobacterium leprae organisms.
- Lepromin test distinguishes lepromatous from tuberculoid type of leprosy.
Treatment
The following anti leprosy medications or antibiotics are commonly used in the treatment of both forms of leprosy:
- Rifampicin
- Dapsone
- Clofazamine
- Fluoroquinolones
- Minocycline
- Erythromycin and other macrolides
Medications may also be given to control the inflammations associated with leprosy, these include:
- Aspirin
- Thalidomide
- Prednisone [10]
Prognosis
Leprosy as a disease is rarely fatal, complications of nerve damage predisposes patients to other morbid events. Early diagnosis and early treatment are paramount in all cases of leprosy. This will limit nerve damage and disability, limit the spread of the disease, and increase the chances of the patient to live a normal life.
Etiology
Leprosy is caused by the acid fast mycobacterium leprae which is not very contagious. The incubation period of M. leprae may take months to years making it almost impossible to pinpoint with certainty where the disease was initially contracted. Children are more likely to contract the disorder compared to their adult counterparts. Leprosy occurs in two forms; the tuberculoid and the lepromatous form.
Both forms will present with skin sores and neuropathies, but the lepromatous forms are more severe in terms of cutaneous presentation. Leprosy is still common in tropical, subtropical, temperate countries. The emergence of the multidrug resistant strains of Mycobacterium leprae have raised global concerns regarding leprosy worldwide [2].
Epidemiology
In the United States, around 205 new cases of leprosy were reported by the Registry of the National Hansen’s Disease Programs as of 2010 [3]. Although majority of this cases are diagnosed among immigrants from foreign countries like Asia, Africa and Latin America. Anthrozoonotic transmission of leprosy has been noted from infected armadillos in the southern part of the United States [4]. Internationally, there has been a significant decline in the prevalence rate of leprosy as of 2010 as compared to baseline data from 2004. In one of the recent prospective studies, newly diagnosed cases of leprosy may exhibit signs of impaired nerve function in up to 56% [5].
Leprosy is still considered to be the most common cause of hand crippling especially those involving the ulnar nerve [6]. There is no racial predilection for leprosy worldwide. There is a 3:2 male to female ratio among leprosy infected patients globally, but in some areas of Africa women are more prone to the disease than men [7]. Age specific incidence of leprosy has a mean age of 10 years old representing almost 20% of all the leprosy cases.
Pathophysiology
The clinical manifestation of leprosy differs significantly according to the cellular response of the infected host. When the host possess a hyperactive cellular response, patients tend to have the tuberculoid form or the paucibacillary form of leprosy characterized by dry cutaneous lesion and hypoesthetic nerves. Skin test and slit test will not reveal any actual bacteria on microscopy but the leprae antigen will test positive in this case. Patients having minimal response exhibit the lepromatous form or the multibacillary form of the disease which is characterized by extensive and severe skin involvement and symmetric nerve dysfunctions. Skin test will herald a positive results of the mycobacterium.
Prevention
The ultimate approach to prevention is to avoid direct close contact with untreated leprosy patients. Patients should submit to immediate treatment after confirmatory diagnosis to reduce the risk of permanent disability and physical disfigurement.
Summary
Leprosy or Hansen’s disease is a chronic infection brought about by the acid fast rod bacilli Mycobacterium leprae. Leprosy is a disease that causes damage to both skin (acutely) and nerves (latent infection) which can manifest from several months to years from exposure.
The World Health Organization (WHO) has launched a global initiative to eradicate the disease and bring down the prevalence rate to less than 1 in 10,000 population in the year 2000. This campaign was successfully met in 2002, save for the 15 out of 122 countries that were previously endemic as of 1985 [1]. Multidrug regimens were used worldwide to treat more than 14 million leprosy patients since 1985. Access to the multidrug medications is still the leading problem in the global leprosy campaign especially in some endemic regions of the world. The WHO is bent on reducing the worldwide incidence rate by 35% by 2015.
Patient Information
Definition
Leprosy or Hansen’s disease is a chronic infection brought about by the acid fast rod bacilli Mycobacterium leprae.
Cause
Leprosy is caused by the acid fast Mycobacterium leprae.
Symptoms
Skin bumps and lumps with hypoesthesia and peripheral neuropathies are common symptoms.
Diagnosis
Diagnosis is done by a detailed clinical history and direct physical examination of the lesions. Confirmatory tests including skin biopsy, skin scraping tests, and lepromin tests may be implored.
Treatment and follow-up
Anti-leprosy medications like rifampicin, dapsone and clofazimine. Anti-inflammatory agents like aspirin, thalidomide, and prednisone may also be used to allay the symptoms.
References
- World Health Organization. Global leprosy situation, 2005. Wkly Epidemiol Rec. Aug 26 2005; 80(34):289-95.
- Joyce MP, Scollard DM. Leprosy (Hansen's Disease). Conn's Current Therapy. 2004; 100-105.
- Truman RW, Singh P, Sharma R, et al. Probable zoonotic leprosy in the southern United States. N Engl J Med. Apr 28 2011; 364(17):1626-33.
- Ustianowski AP, Lockwood DN. Leprosy: current diagnostic and treatment approaches. Curr Opin Infect Dis. Oct 2003; 16(5):421-7.
- Anderson GA. The surgical management of deformities of the hand in leprosy. J Bone Joint Surg Br. Mar 2006; 88(3):290-4.
- Scollard DM, Adams LB, Gillis TP, Krahenbuhl JL, Truman RW, Williams DL. The continuing challenges of leprosy. Clin Microbiol Rev. Apr 2006; 19(2):338-81.
- Walker SL, Lockwood DN. Leprosy. Clin Dermatol. Mar-Apr 2007; 25(2):165-72.
- Anderson H, Stryjewska B, Boyanton BL, et al. Hansen disease in the United States in the 21st century: a review of the literature. Arch Pathol Lab Med. Jun 2007; 131(6):982-6.
- Van Veen NH, Nicholls PG, Smith WC, Richardus JH. Corticosteroids for treating nerve damage in leprosy. Cochrane Database Syst Rev. Apr 18 2007; CD005491.
- Kai M, Nguyen Phuc NH, et al. Analysis of Drug-Resistant Strains of Mycobacterium leprae in an Endemic Area of Vietnam. Clin Infect Dis. Mar 2011; 52(5):e127-32.