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Cranial and vertebral magnetic resonance imaging revealed destruction of the second thoracic vertebra and a major paravertebral abscess, causing cord compression, which suggests tuberculous spondylitis. The diagnosis of Mycobacterium tuberculosiswas confirmed by polymerase chain reaction assay on samples of the cutaneous lesion biopsy material and dorsal abscess. After 2 months of taking 4 antituberculous drugs, the patient completed 16 months of treatment with isoniazid and rifampin.

Computed tomography–guided abscess drainage was initially performed, which resulted in a partial reduction in abscess volume. During the second week of therapy, the patient underwent anterior debridement and drainage through costotransversectomy and posterior spinal–instrumented fusion. The patient had an uneventful recovery, regaining normal gait with full motor strength in both lower extremities. Complete healing of the cutaneous ulcer was achieved after 8 weeks of treatment, and spinal fusion was documented at 12 months.

Tuberculosis remains a global epidemic.¹Children and adolescents are more prone to develop the disease after infection than adults. Bone and joint infections account for less than 6% of tuberculosis cases,²and cutaneous tuberculosis is even more rare,³occurring in less than 1% of cases of tuberculosis. It can be acquired endogenously or exogenously and may have various manifestations, including erythematous rashes, nodules, and chronic ulcerative or verrucose forms.⁴Published case series show that up to one-third of patients with cutaneous tuberculosis also have other forms of systemic disease.^5- 6Therefore, chest and vertebral radiographs should be considered in all patients with cutaneous tuberculosis, as lung and vertebral disease are the most frequent foci of concomitant infection in these patients. History and physical examination findings should disclose other possible foci (eg, tuberculous adenitis) and guide further diagnostic evaluation.

The effectiveness of diagnostic methods for cutaneous tuberculosis varies with infection route, the patient's immune system capability, and disease manifestations.⁴Tuberculin skin testing (Mantoux test) results are usually positive in immunocompetent patients who acquire the disease by direct inoculation. However, smears for acid-fast bacilli and cultures may be negative because these are paucibacillary disease forms. Endogenously acquired cutaneous disease is frequently associated with variable degrees of immunosuppression (especially with cutaneous abscesses and orificial and miliary cutaneous tuberculosis). Accordingly, tuberculin skin testing responses may be anergic as a result of impaired cell-mediated immunity and decreased delayed hypersensitivity reaction.

This clinical case represents a rare association between tuberculous spondylitis and cutaneous tuberculosis. More frequently implicated as a cause of cutaneous ulcers are Mycobacteriumin M tuberculosiscomplex (including M bovisand the bacille Calmette-Guérin–attenuated form of M bovis). Other mycobacteria acquired through direct skin inoculation may cause cutaneous lesions in children: M marinum(found in saltwater and freshwater, tropical fish tanks, and swimming pools), M ulcerans(found in tropical rain forests; causes Buruli ulcers), and others found more readily in the environment (M fortuitumand M aviumcomplex and M kansasii).⁷Other infectious causes, particularly in tropical climates, include deep and subcutaneous mycosis (eg, blastomycosis, chromoblastomycosis, and mycetoma), tropical ulcer (infection with fusospirillary bacteria association), localized cutaneous leishmaniasis, and cutaneous diphtheria. Other possible causes for chronic ulcerations are late syphilis (cutaneous gummas in tertiary stage), other treponematosis (yaws or endemic syphilis), leprosy, tularemia, and actinomycosis.

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Correspondence:Isabel Castro Esteves, MD, Pediatric Infectious Diseases Unit, Child and Family Department, Hospital de Santa Maria, Avenida Professor Egas Moniz, 1649-035 Lisbon, Portugal (isabel.castro.menezes@gmail.com).

Accepted for Publication:April 29, 2009.

Author Contributions:Study concept and design: Esteves and Marques. Acquisition of data: Esteves. Analysis and interpretation of data: Esteves and Fernandes. Drafting of the manuscript: Esteves. Critical revision of the manuscript for important intellectual content: Esteves, Fernandes, and Marques. Administrative, technical, and material support: Esteves. Study supervision: Esteves and Marques.

Financial Disclosure:None reported.

Additional Contributions:Odete Valério, MD, and Filipa Osório, MD, of the Breast Diagnostic Clinic of the Gynecology and Obstetrics Department of the Santa Maria Hospital collaborated in the topical treatment of the cutaneous lesion and provided photographs documenting it.