Cutaneous tuberculosis (TB) can be caused by M. tuberculosis, M. bovis, and the Bacillus Calmette–Guérin (BCG) vaccine. The disease has diverse clinical features that can follow immune-mediated processes or endogenous and exogenous spread of the microorganism. The exogenous spread is less common. Even though cutaneous TB comprises less than 1% of all TB cases, it is important to consider it when a clinical picture suggestive of it is found [1]. Exogenous inoculation develops after M. tuberculosis is directly inoculated into the skin of an individual susceptible to the infection. This results in tuberculosis verrucosa cutis (TVC), TB chancre, and in some cases lupus vulgaris (LV). Endogenous spread occurs in previously infected cases by means of contiguous extension, hematogenous dissemination or through lymphatic circulation or in old scars of scrofuloderma [2]. Hematogenous spread is observed in LV, acute miliary TB, papulonecrotic tuberculoid (PNT), and metastatic TB abscess (gummatous TB). A contiguous extension can be seen in orificial TB and scrofuloderma.

LV is the most common type of cutaneous TB and affects females 2 to 3 times more often than males. It is chronic and progressive.The lesions of LV are commonly found in the region of the head and neck [3] and are generally solitary, small, sharply defined, nodular, reddish brown, with a gelatinous consistency (apple jelly nodules). In western countries, these lesions usually appear on the head and neck while in tropical or subtropical regions they develop on lower extremities and the buttocks.

The existing clinical variations are as follows:

• Classic plaque
• Keratotic
• Hypertrophic
• Ulcerative
• Vegetating

The classic plaques begin as discrete red-brown papules. They coalesce and form soft and gelatinous (apple-jelly) plaques with central atrophy and elevated verrucas border.

Persistent lesions become ulcerated and damage the underlying structures leading to disfigurement and have an increased risk of malignant transformation.

• Foul Smelling Discharge

  There was a foul smelling discharging sinus over outer aspect of right elbow [Figure - 1]. A similar sinus was present over medial aspect of lower 1/3 of left leg. Multiple scar marks were seen on the sides of neck. [ijdvl.com]

  CASE REPORT A 73-year-old male patient consulted to our outpatient clinics with complaints of ever-increasing number of non-healing wounds with foul-smelling discharge. [ncbi.nlm.nih.gov]

• Intermittent Fever

  The patient had a history of intermittent fever for the past 3 years. There was no history of weight loss or any other systemic complaints. There was no previous history of TB in the patient or family. [ijmyco.org]

• Plethora

  CTB includes a morphological plethora with primary-inoculation TB, tuberculous chancre, scrofuloderma, TB periorificialis and acute military TB in the multibacillary spectrum. [ijmm.org]

• Vietnamese

  Lupus vulgaris 180 millions of speakers Translator English - Japanese 尋常性狼瘡 130 millions of speakers Translator English - Korean 루푸스 심상 85 millions of speakers Translator English - Javanese Lupus vulgaris 85 millions of speakers Translator English - Vietnamese [educalingo.com]

• Cervical Lymphadenopathy

  General and systemic examinations findings were insignificant, except for bilateral cervical lymphadenopathy. The body mass index was 16.6 Kg/m 2. [smjonline.org]

  RDD, originally known as sinus histiocytosis with massive lymphadenopathy, is a benign histiocytic proliferative disorder characterized clinically by a massive, painless, often bilateral cervical lymphadenopathy accompanied by fever, neutrophilia, anemia [scielo.br]

  Discussion BCG immunization has some complications include: Local reaction such as axillary or cervical lymphadenopathy, local subcutaneous abscess and keloids, skin lesions distinct from the vaccination site such as TB chancre, lupus vulgaris, scrofuloderma [pedinfect.com]

  Bilateral cervical lymphadenopathy was present. The rest of the systemic findings and vitals were normal. Considering the possibilities of sporotrichosis, chromoblastomycosis, cutaneous leishmaniasis and CTB, a skin biopsy was taken. [ijmm.org]

• Inguinal Lymphadenopathy

  There were also multiple inguinal lymphadenopathies. On the diascopy test, “apple jelly” sign was negative. [ijmyco.org]

• Lesion of the Pinna

  […] involving the pinna and may present the clinician with a diagnostic dilemma. [indianjotol.org]

• Skin Disease

  Diseases Skin Diseases, Infectious Skin Diseases, Bacterial Tuberculosis, Cutaneous Diseases Bacterial Infections and Mycoses Infection Skin Diseases, Infectious Skin Diseases, Bacterial Tuberculosis, Cutaneous Bacterial Infections Skin Diseases, Bacterial [hon.ch]

  The term "lupus" to describe an ulcerative skin disease dates to the late thirteenth century, though it was not until the mid-nineteenth that two specific skin diseases were classified as Lupus erythematosus and Lupus vulgaris. [diki.pl]

  These findings are repetitively reported as suggestive for granulomatous skin diseases such as sarcoidosis, tuberculosis, and granuloma annulare. [hindawi.com]

• Cutaneous Manifestation

  Leprosy predominantly presents through skin manifestations whereas cutaneous manifestations of TB though not so frequent but are not rare. [ncbi.nlm.nih.gov]

  Cutaneous manifestations of secondary syphilis are protean and skin tuberculosis may be considered in the differential diagnosis, especially in HIV-infected patients. [moh-it.pure.elsevier.com]

• Skin Ulcer

  There were multiple, nontender skin ulcers on bilateral lumbar areas, some oozing serosanguinous discharge and few others with scarring [Figure 1]. [lungindia.com]

  If left untreated, the skin lesions can mature into skin ulcers. The term 'serpiginosus' means 'slow, snakelike' movement over the body, which leaves scarring. [wellcomecollection.org]

• Facial Skin Lesion

  [Crossref] Werschler WP, Elgart ML, Williams CM (1990) Progressive asymptomatic annular facial skin lesions. Cutaneous tuberculosis (lupus vulgaris). Arch Dermatol 126: 1227-1230. [oatext.com]

• Skin Plaque

  Histopathological examination of skin plaque showed typical tuberculoid granulomas in the dermis. However blood sugar, sputum for AFB, LFT including serum enzymes were within normal limits. Blood sent for HIV was found to be negative. [ijdvl.com]

• Malar Rash

  Malar Rash About half of people with lupus experience a characteristic red “malar” rash or color change that may appear across the cheeks and bridge of the nose in the shape of a butterfly. [lupusresearch.org]

  Some people with lupus have a red rash over their cheeks and the bridge of their nose -- called a "butterfly" or malar rash. Hair loss and mouth sores are also common. [webmd.com]

  Rashes: butterfly-shaped rash over the cheeks - referred to as malar rash red rash with raised round or oval patches - known as discoid rash rash on skin exposed to the sun Mouth sores: sores in the mouth or nose lasting from a few days to more than a [rheumatology.org]

  Systemic lupus erythematosus Share on Pinterest A malar rash is a key symptom of lupus. Image credit: Doktorinternet, 2013. SLE is the most familiar type of lupus. It is a systemic condition. This means it has an impact throughout the body. [medicalnewstoday.com]

  rash (malar discoid rash not counted), bullous lupus, toxic epidermal necrolysis variant of SLE, maculopapular lupus rash, photosensitive lupus rash (in the absence of dermatomyositis) or Subacute cutaneous lupus (nonindurated psoriaform and/or annular [merckmanuals.com]

• Facial Ulceration

  Original Article O Fatusi, O Onayemi, K Adebiyi, V Adetiloye, F Owotade, O Oninla Keywords facial ulcer, histopathological diagnosis, lupus vulgaris, tuberculosis cutis orificialis Citation O Fatusi, O Onayemi, K Adebiyi, V Adetiloye, F Owotade, O Oninla [ispub.com]

• Neglect

  Here, we report a 56 year-old patient diagnosed with skin squamous cell carcinoma and with a 30 year course of neglected lupus vulgaris, which was very rare. [ncbi.nlm.nih.gov]

  The buttocks are common but often neglected sites for lupus vulgaris in children. We present a case report of lupus vulgaris occurring on the buttocks, and discuss our approach in diagnosis and treatment. [content.iospress.com]

  Facial lupus vulgaris neglected for 50 years. [jddsjournal.org]

The diagnosis of LV can be a challenging task as the skin changes are atypical and there is a paucity of TB bacilli in the lesions.

Skin biopsy and histology may show tubercules or tuberculoid granulomas without caseation in the papillary dermis with few or no bacilli, and variable epidermal hyperplasia [4] [5]. If a superficial biopsy is obtained then pseudo-epithelial hyperplasia with a non-specific inflammatory cell infiltrate may be observed, missing the features of LV [6].

Identification of Mycobacteria is essential for the definitive diagnosis of cutaneous TB but this is usually impossible since there are few bacilli. M. tuberculosis rarely grows on culture when the sample is taken from a patient with high levels of immunity or from chronic lesions.

Special tests like the polymerase chain reaction (PCR) can be performed to confirm the diagnosis or when the histopathological findings are not characteristic of the condition [7].

Ziehl-Neelsen staining and PCR may also give negative results in LV due to the paucity of TB bacilli [8] [9].

Diagnosis relies heavily on clinical features, histopathological findings, a positive purified protein derivative test (PPD) and response to anti-TB medication [2] [10].

The differential diagnosis of cutaneous TB includes leprosy, leishmaniasis, syphilis, actinomycosis, and deep mycosis.

• Skin Test Positive

  Verhagen et al demonstrated that large clusters of TB are associated with an increased number of tuberculin skin test–positive contacts, even after adjusting for other risk factors for transmission. [24] The number of positive contacts was significantly [emedicine.com]

• Mycobacterium Fortuitum

  We report a woman with a lupus vulgaris-like skin eruption caused by Mycobacterium fortuitum. [ncbi.nlm.nih.gov]

  Mycobacterium fortuitum infection arising in a new tattoo. Dermatol Online J. 2014;15:20. [ijord.com]

• Granulomatous Tissue

  CLINICAL FEATURES The skin covering the inflamed lymph nodes becomes indurated, purplish in color followed by ulceration with crusty ,irregular pale granulomatous tissue ending in scarring. [drmhijazy.com]

1. Rai VM, Shenoi SD, Gowrinath K. Tuberculous gluteal abscess coexisting with scrofuloderma and tubercular lymphadenitis. Dermatol Online J. 2005;11(3):14.
2. Marcoval J, Servitje O, Moreno A, et al. Lupus vulgaris. Clinical, histopathologic, and bacteriologic study of 10 cases. J Am Acad Dermatol. 1992;26(3 Pt 2):404–407.
3. Barbagallo J, Tager P, Ingleton R, Hirsch RJ, Weinberg JM. Cutaneous tuberculosis: diagnosis and treatment. Am J Clin Dermatol 2002;3(5):319-328.
4. Farina MC, Gegundez MI, Pique E, et al. Cutaneous tuberculosis: a clinical, histopathologic, and bacteriologic study. J Am Acad Dermatol. 1995;33:433–440.
5. Tan SH, Tan BH, Goh CL, et al. Detection of Mycobacterium tuberculosis DNA using polymerase chain reaction in cutaneous tuberculosis and tuberculids. Int J Dermatol. 1999;38:122–127.
6. Andrew PW, Edward WJ. Cutaneous tuberculosis of the nose with unusual clinical and histological features leading to a delay in the diagnosis. Clin exp Dermatol. 1977;2:235-242.
7. Khandpur S, Reddy BS. Lupus vulgaris: Unusual presentations over the face. J Eur Acad Dermatol Venereol. 2003;17:706-710.
8. Sehgal V. Cutaneous tuberculosis. Dermatol Clin. 1994;12:645–53.
9. Aliağaoğlu C, Atasoy M, Güleç AI. Lupus vulgaris: 30 years of experience from eastern Turkey. Clin Exp Dermatol. 2009;34:e289.
10. İnönü H, Sezer E, Doruk S, Koseoglu D. Cutaneous tuberculosis: report of three lupus vulgaris cases: original image. Turkiye Klinikleri J Med Sci. 2009;29:788–91.