It is important to consider mycobacterial infection in any stubborn and atypical skin problem in immunocompromised individuals. Mycobacteria cause slowly developing chronic skin infections. Mycobacterial infection is increasing, partly due to emerging drug resistance and the HIV epidemic.
- This is the most common form of cutaneous tuberculosis, occurring after primary infection in individuals with good natural resistance.
- Females are more often affected and it is also more common in children.
- Most commonly, it affects the face and neck and is seen initially as firm, translucent, brown nodules.
- Without treatment, the lesions slowly spread laterally, leading to disfiguring scarring. Malignant change has been reported in these scars.
- Diagnosis is confirmed by biopsy and culture. Patients should receive full antituberculous therapy for at least one year.
- Add notes to any clinical page and create a reflective diary
- Automatically track and log every page you have viewed
- Print and export a summary to use in your appraisal
- Scrofuloderma results from breakdown of skin overlying a tuberculous focus, usually at a lymph node but also at the skin over infected bones or joints.
- Lesions present as firm, painless, subcutaneous nodules that gradually enlarge and suppurate, then form ulcers and sinus tracts in overlying skin. Typical ulcers have undermined edges and a floor of granulation tissue. It causes fistulae and scarring.
- Mycobacterium tuberculosis can be identified both in the nodes and in the material draining on to the skin surface.
- Full antituberculous therapy and surgical excision are required.
- Also known as tuberculosis verrucosa cutis.
- This is the most common form of cutaneous tuberculosis in developing countries but it is rare in western countries.
- It occurs with infection in someone who has immunity from previous infection.
- It causes a warty plaque, often on the hands, knees or buttocks.
See separate related article Leprosy.
- Leprosy is a disease of overcrowding, poor hygiene and poverty.
- Hypopigmented anaesthetic macules, plaques, papules, or annular lesions (with raised erythematous rims).
- There are many lesions in lepromatous leprosy but just a few asymmetrical, hypopigmented lesions in tuberculoid leprosy.
- Areas of anaesthesia may occur, along with damage to autonomic fibres, causing loss of sweating within that area.
- Patients with leprosy often suffer skin damage, eg burns, because of anaesthesia caused by nerve damage due to the primary infection.
- The cutaneous manifestation is likely to be a single macule or plaque, which is erythematous or purple (depigmentation often seen on coloured skin) and has a raised edge sloping towards a flattened hypopigmented centre.
- The surface is anaesthetised, dry, and hairless.
- The depigmented areas may resemble vitiligo.
- No Mycobacterium leprae is found in skin smears.
- There is a good prognosis and many infections resolve without treatment; peripheral nerve damage is limited.
- In borderline cases, the lesions are similar but more numerous.
- Hypopigmented or erythematous macules, papules, nodules and ulceration develop at sites of low temperature, eg nostrils (may lead to septal perforation and collapse of the nasal bones).
- Generalised thickening of involved facial tissues causes leonine facies.
- Loss of hair and sweating and progressive glove and stocking sensory loss.
- Damage to peripheral nerves is symmetrical and occurs late in the disease.
- Bone involvement is common.
Erythema nodosum leprosum
- This occurs in lepromatous disease, especially during the first year of treatment.
- Painful red nodules on the face and extensor surfaces.
- Fever and malaise may be accompanied by uveitis, arthritis, neuritis, lymphadenitis, and orchitis.
- Attacks are acute and may recur over several years.
See separate article on Leprosy for diagnosis and treatment.
- Cutaneous infections with atypical mycobacterium are much more common in immunosuppressed patients, especially those with HIV infection, leukaemia or those undergoing immunosuppressive therapy.
- Atypical mycobacterial infections are also more common in the elderly.
- The environmental mycobacteria cause two named diseases with characteristic features:
- Swimming pool (or fish tank) granuloma caused by Mycobacterium marinum.
- Buruli ulcer caused by Mycobacterium ulcerans infection.
- The other mycobacterioses are much less specific, often resembling tuberculosis.
- Buruli ulcer is also known as Bairnsdale ulcer or Searls' ulcer, (Australia) and Kakerifu ulcer or Toro ulcer (Congo).
- Is a re-emerging infection and is now the third most prevalent mycobacterial disease worldwide, behind tuberculosis and leprosy.
- It is due to infection by M. ulcerans in tropical zones - acquired from vegetation or water after trauma.
- Initially a painless erythematous nodule develops, usually on the leg or forearm. This eventually becomes necrotic and ulcerates.
- Treatment is usually by wide surgical excision - antimicrobial therapy with rifampicin and clarithromycin is recommended before and after surgery.
- Bacillus Calmette-Guérin (BCG) vaccine gives short-term prevention.
See separate article Buruli Ulcer.
Fish tank granuloma (or swimming pool granuloma)
- This is caused by M. marinum infection, which infects fish and is also found in swimming pools.
- Typically, it causes a reddish, slightly scaly plaque on the hand or arm of someone who keeps tropical fish.
- M. marinum is sensitive to minocycline, clarithromycin, amikacin, rifampicin, ethambutol and doxycycline.
Other environmental mycobacteria
- Mycobacterium kansasii:
- Most patients who present with localised primary cutaneous M. kansasii infection are immunocompetent, whereas most patients with disseminated or pulmonary infection are immunocompromised.
- It may resemble cellulitis or sporotrichosis.
- It may also present with tenosynovitis, cutaneous lymphadenitis; the clinical presentation is similar to that expected in lupus profundus and with ulcerative perineal lesions.
- Mycobacterium malmoense: cervical lymphadenitis in preschool-aged children. It has also been associated with cutaneous nodules on the hands.
- Mycobacterium szulgai: cellulitis, nodules and plaques.
- A case of disseminated Mycobacterium simiae infection with blood, pulmonary, and cutaneous localisation has been reported.
- Mycobacterium gordonae: granulomatous synovitis and bursitis. It is sometimes called tap water scotochromogen. It has also caused granulomatous nodules on the back of the hand.
- Mycobacterium haemophilum: multiple, tender, cutaneous nodules, which may develop into ulcers or abscesses. They are often situated over limb joints. May lead to muscle wasting, tenosynovitis, and joint effusions.
- Mycobacterium avium complex (MAC)[/i}: this has emerged as a major human pathogen. Cutaneous disease is caused by direct inoculation (trauma, surgery, injection) and is characterised by skin lesions, such as ulceration, abscess, or erythematous plaque.
- This mainly affects otherwise healthy children aged under five years.
- It usually affects the cervical lymph nodes, often just a single node.
- Is caused by many mycobacterial species, most often M. avium complex (MAC) and Mycobacterium scrofulaceum.
- Infection in older children and more diffuse involvement are often associated with HIV infection.
- Surgical excision is curative.
- Careful clinical examination is the gold standard.
- The optimal way to make the diagnosis is by performing a culture of tissue. Most mycobacteria require special culture conditions, which, if not specifically requested, are frequently not used.
- The development of DNA fingerprinting technology, especially pulsed-field gel electrophoresis, has been suggested as a diagnostic tool.
- Polymerase chain reaction has been used to aid diagnosis.
- CXR: associated pulmonary disease.
- The purified protein derivative test (antigen skin test used to aid the diagnosis of tuberculosis) result is usually negative in infections with atypical mycobacteria.
- Effective treatment depends on precise diagnosis and identification of the underlying organism. Treatment will also be governed by results of culture and sensitivity.
- Treatment of atypical mycobacterial skin infections is often difficult because many atypical mycobacteria are resistant to common antibiotics.
- A combined therapeutic approach, including surgical drainage, debridement, and prolonged treatment with combined antimicrobial agents, has been used in some cases of atypical mycobacteria.
- In some cases (especially fast-growing environmental mycobacteria), successful treatment requires aggressive debridement of all infected subcutaneous tissues and skin.
- Scarring and nerve damage can occur from long-standing untreated infections.
- The prognosis is good with proper medical and surgical treatment.
- However, many patients are often not properly treated because of insufficient health resources in developing countries, or treatment may be difficult because of underlying immunosuppression and consequent diffuse infection.
- Avoidance of contaminant material.
- BCG vaccination gives a variable degree and duration of protection.
Further reading & references
- Barbagallo J, Tager P, Ingleton R, et al; Cutaneous tuberculosis: diagnosis and treatment. Am J Clin Dermatol. 2002;3(5):319-28.
- Hijazy M; Principles of Paediatric Dermatology (2008)
- Bonnet F, Lewden C, May T, et al; Opportunistic infections as causes of death in HIV-infected patients in the HAART era in France. Scand J Infect Dis. 2005;37(6-7):482-7.
- Padmavathy L, Lakshmana Rao L, Ethirajan N, et al; Tuberculosis verrucosa cutis (TBVC)--foot with miliary tuberculosis. Indian J Tuberc. 2007 Jul;54(3):145-8.
- Das JK, Sengupta S, Mitra S, et al; Coexistence of papulonecrotic tuberculide with lichen scrofulosorum. Indian J Dermatol. 2010;55(1):109-12.
- Lewis FS et al; Dermatologic Manifestations of Leprosy, Medscape, Feb 2010
- Kahawita IP, Lockwood DN; Towards understanding the pathology of erythema nodosum leprosum. Trans R Soc Trop Med Hyg. 2008 Apr;102(4):329-37. Epub 2008 Mar 3.
- Dieudonne A et al; Atypical Mycobacterial Infection, Medscape, Sep 2009
- Scheinfeld NS; Atypical Mycobacterial Diseases, Medscape, Aug 2010
- Zumla A, Grange J; Infection and disease caused by environmental mycobacteria. Curr Opin Pulm Med. 2002 May;8(3):166-72.
- Kirby JS et al; Dermatologic Manifestations of Mycobacterium Marinum Infection of the Skin, Medscape, Jul 2009
- Mahaisavariya P, Chaiprasert A, Khemngern S, et al; Nontuberculous mycobacterial skin infections: clinical and bacteriological studies. J Med Assoc Thai. 2003 Jan;86(1):52-60.
- Ferreira CP, Coutinho ZF, Lourenco MC, et al; Atypical cutaneous mycobacteriosis caused by Mycobacterium avium complex. Braz J Infect Dis. 2010 May-Jun;14(3):324-6.
- Scheinfeld N et al; Dermatologic Manifestations of Mycobacterium Avium-Intracellulare Infection, Medscape, Aug 2010
- Weitzul S, Eichhorn PJ, Pandya AG; Nontuberculous mycobacterial infections of the skin. Dermatol Clin. 2000 Apr;18(2):359-77, xi-xii.
- Abdalla CM, de Oliveira ZN, Sotto MN, et al; Polymerase chain reaction compared to other laboratory findings and to clinical Int J Dermatol. 2009 Jan;48(1):27-35.
- Streit M, Bregenzer T, Heinzer I; [Cutaneous infections due to atypical mycobacteria] Hautarzt. 2008 Jan;59(1):59-70; quiz 71.
|Original Author: Dr Colin Tidy||Current Version: Dr Laurence Knott|
|Last Checked: 23/05/2011||Document ID: 2480 Version: 23||© EMIS|
Disclaimer: This article is for information only and should not be used for the diagnosis or treatment of medical conditions. EMIS has used all reasonable care in compiling the information but make no warranty as to its accuracy. Consult a doctor or other health care professional for diagnosis and treatment of medical conditions. For details see our conditions.