Cutaneous tuberculosis A18.4

A classic infectious disease that occurs worldwide and is notifiable by name, most commonly affecting the lungs, intrathoracic lymph nodes, bronchi and pleura. Tuberculosis of the urogenital tract, peripheral lymph nodes, bones, joints and skin is not uncommon.

For further information see below. Tuberculosis cutis (overview)

Pathogen: Mycobacterium tuberculosis complex.

This includes the following species:

• (M.) tuberculosis (99%; human as reservoir)
• M. bovis (bovine tuberculosis)
• M. africanum (human as reservoir, see mycobacteria).

The disease can start highly acute, acute, subacute, chronic and also asymptomatic. Untreated relapsing course.

A distinction is made between:

• primary cutaneous tuberculosis
• post-primary tuberculosis.

Primary cutaneous tuberculosis: the primary tuberculous complex of the skin as an exogenous primary infection through direct contact of an injured skin site with tuberculous material and the formation of a nodular infiltrate with caseation and ulceration as well as regional lymphadenitis is rare.

Postprimary tuberculosis: postprimary cutaneous tuberculosis may develop by inoculation or by endogenous spread.

Depending on the immune status, the following clinical pictures develop (see table):

• Tuberculosis cutis luposa
• Tuberculosis cutis colliquativa
• Tuberculosis cutis verrucosa
• Tuberculosis fungosa serpiginosa
• Tuberculosis cutis miliaris disseminata
• Tuberculosis subcutanea et fistulosa.

Primary tuberculous complex of the skin as an exogenous primary infection due to direct contact of an injured skin site with tuberculous material and the formation of a nodular infiltrate with caseation and ulceration as well as regional lymphadenitis is rare.

An estimated 1/3 of humanity is infected with tuberculosis pathogens. Around 15% of those infected develop active tuberculosis. About 95% of cases and deaths occur in developing countries. In addition to the general nutritional status, the high HIV infestation is responsible for this.

The average incidence in Germany is 5.4/100,000 inhabitants/year. It is higher in various risk groups (HIV-infected persons). It is significantly higher in various risk groups (HIV-infected persons, immunosuppressed persons, drug addicts, malnourished persons, migrants from high-risk countries).

TB is the most common cause of death in AIDS patients. Multidrug-resistant tuberculosis (MDR = resistance to at least INH+RMP) is becoming an increasing problem (the number of infected people worldwide is estimated at 50 million). Countries with a high burden of MDR tuberculosis are (according to WHO, as of 2013: Belarus, Ethiopia, Armenia, Azerbaijan, Bangladesh, Bulgaria, China, Congo, Estonia, Georgia, India, Indonesia, Kazakhstan, Kyrgyzstan, Latvia, Lithuania, Moldova, Myanmar, Nigeria, Pakistan, Philippines, Russia, South Africa, Tajikistan, Ukraine, Uzbekistan, Vietnam). In the Philippines, the incidence in 2016 was 544 cases per 100,000 inhabitants (Veronese F et al. 2020).

Cutaneous tuberculosis represents 1-4% of all forms of tuberculosis. Among patients with extrapulmonary tuberculosis, 1-2% suffer from cutaneous tuberculosis (Veronese F et al. 2020).

Transmission most often by droplet infection, rarely by skin contact with infected material or through food.

Microscopic(Ziehl-Neelsen staining) or cultural pathogen detection (only culture and animal testing are reliable - see mycobacteria below) from biopsy material.

The Quantiferon-TB-Gold test has become established as a serological detection method. This is a highly sensitive immunological test for tuberculosis screening in which the tuberculosis-specific antigens ESAT-6 (early secretory antigen target-6), CFP-10 (culture filtrate protein 10) and TB 7.7(p4) are used. These are only found in M. tuberculosis and M. bovis.

Skin tuberculosis

1. Gramminger C et al. (2025) Recognizing cutaneous tuberculosis. J Dtsch Dermatol Ges 23:793-802.
2. Koch R (1882) The aetiology of tuberculosis. Berliner klinische Wochenschrift 19: 221-230
3. Koch R (1884) The aetiology of tuberculosis. Mittheilungen aus dem Kaiserlichen Gesundsheitsamte 2: 1-88
4. Mello RB, Vale ECSD, Baeta IGR. Scrofuloderma: a diagnostic challenge. An Bras Dermatol. 2019 Jan-Feb;94(1):102-104.
5. Peters F et al. (2016) Germ or no germ: challenges in the diagnosis of mycobacterial infections of the skin. J Dtsch Dermatol Ges 14:1227-1236
6. Schmekal B et al. (2002) Skin tuberculosis with atypical mycobacteria 8 years after combined pancreas-kidney transplantation. Am J Nephrol 22: 566-568
7. Senol M et al. (2003) A case of lupus vulgaris with unusual location. J Dermatol 30: 566-569
8. Utikal J et al (2003) Cutaneous non-Langerhans' cell histiocytoses. J Dtsch Dermatol Ges 1: 471-491
9. van Zyl L et al. (2015) Cutaneous tuberculosis overview andcurrent treatment regimens. Tuberculosis (Edinb) 95:629-638
10. Veronese F et al (2020) Disseminated ulcers with sporotrichoid distribution. J Dtsch Dermatol Ges 18:153-156.