Volume 5, Issue 3 , Pages 118-120, September 2010
Tuberculous retropharyngeal abscess with posterior mediastinal extension and quadriplegia in a 13-year-old Nigerian girl
Article Outline
Abstract
Neglected cervical tuberculosis (TB) in a 13-year-old girl with extensive prevertebral abscess extending from C1-T4 is presented along with the plain radiographic and computed tomographic findings. The tuberculous infection progresses to cause multiple vertebral destructions and quadriplegia due to delayed diagnosis. The diagnosis was made on radiological imaging and confirmed by positive mycobacterium bacilli culture. This case illustrated that delayed diagnosis and treatment of cervical spinal TB can be catastrophic. Hence, we suggest consideration of TB of the spine in the differential diagnosis of any patient presenting with neck/back pain since it can be successfully treated, especially if detected early. We advocated the use of easy operating and low-cost examinations such as tuberculin skin test, abscess puncture (not cut) and pus cultivation especially in developing countries for early diagnosis TB infection.
Keywords: Prevertebral abscess, Quadriplegia, Retropharyngeal abscess, Spine, Tuberculosis
1. Introduction
Skeletal tuberculosis (TB) constitutes 1–3% of extrapulmonary TB, and typically involves the spine in about 50% of cases [1], [2], [3]. Spinal TB is considered the most dangerous because involvement of the spinal cord results in neurologic impairment [1], [2], [3], [4], [5], [6], [7]. Lumbar and thoracic regions are more often involved [1], [2], [5].
Cervical spine is involved in about 2–3% of cases and all ages can be affected [3], [5]. Nonetheless, the diagnosis of TB spine is often not made until complication had set in because it is not frequently considered in the differential diagnosis of many spinal conditions affecting patients of all ages [1], [5]. Paraplegia and paraparesis are the frequent complications [3], [4], [5], [6], [7], [8], [9]. According to Hsu and Leong [4], cervical TB in children is characterised by more diffuse/extensive involvement, formation of large abscesses and lower incidence of Pott's paraplegia or tetraplegia. This is unlike in adults where it is usually more localised and produced less pus, but a higher incidence of paraplegia. Thus, familiarity with the imaging features of TB of the spine may enable a more rapid diagnosis to be made, thereby preventing a delay in diagnosis with its consequent complications [1].
Quadriplegia, an uncommon complication of cervical tuberculosis, in a 13-year-old Nigerian girl with extensive retropharyngeal/prevertebral abscesses and wide cervico-thoracic vertebral and ribs destructions is reported.
2. Case report
A 13-year-old girl was referred from a Federal Medical Centre to our tertiary hospital with 8 months history of fever, neck swelling, weight loss and dysphagia, and 2 months history of progressive body weakness and inability to walk or move both upper limbs.
On admission, she was pale (Pack cell volume of 29%), weighed 24
kg and febrile (38°C). Both upper and lower limbs showed marked soft tissue wasting, extreme weakness (power in all limbs was grade 0) and complete sensory loss in all the limbs. The neck was swollen, non-tender and had associated cervical lymphadenopathy. Throat examination findings of hyperaemic and granular pharynx with narrowed orapharyngeal airway led to the diagnosis of an inflamed retropharyngeal mass.
She had raised ESR (35mm/h), normal urea and electrolytes and tested negative for retrovirus.
Lateral neck radiograph showed widened prevertebral and retropharyngeal soft tissue spaces of 5.5cm, anteriorly displaced airways with narrowed saggital diameter and extension of the retropharyngeal mass into the thorax (Fig. 1). Computerized tomographic scan findings were diagnostic of retropharyngeal abscess (Fig. 2). The abscess extends from C1-T4 in the prevertebral space. There was patchy lytic destruction of the vertebral bodies of C2-T3, posterior ends of the first 3 ribs and laminar of C5–7. These culminated into cervical kyphosis (Fig. 1a and b). There was extension of the abscess with some fragments of the bones into the spinal canal compressing on the cord (Fig. 2a and b). The mass showed minimal ring-like enhancement with contrast.
Fig. 1.
a and b: 13-year-old girl with tuberculous retropharyngeal abscess. (a) Lateral neck radiograph and (b) CT scanogram showing widened retropharyngeal space extending retrosternaly as far as demonstrated. Note the cervical kyphosis, the anterior displacement of the pharynx and the trachea and the partial destruction of the cervical vertebral bodies.
Fig. 2.
a and b: 13-year-old girl with tuberculous retropharyngeal abscess. Axial computed tomographic images (a) root of the neck and (b) thoracic, showing patchy lytic destruction of the vertebral bodies, laminae and posterior ribs. Note the retropharyngeal/prevertebral abscesses, the anteriorly displaced trachea with narrowed saggital diameter, some bony fragments within the spinal canal and the intra-spinal extension of the abscess.
She was commenced on anti-Koch's therapy, while been planned for drainage, but she lapsed into coma and died of respiratory failure.
Autopsy findings revealed a large retropharyngeal abscess associated long segment compression of the tracheal from the root of the neck to about its bifurcation. There were extensive vertebral and rib destructions. Zeil–Nelson's (ZN) stain of the retropharyngeal aspirate was positive for mycobacterium tubercle bacilli. Hence, the confirmation of tuberculous retropharyngeal abscess.
3. Discussion
Spinal TB, less commonly involves the cervical spine [1], [2], [3], [4], [5], [6], [7], [8], [9]. It can affect any vertebra and the rare prespinal abscess mode of presentation does occur [6], [7], [8], [9], [10], [11], [12], [13]. When the cervical spine is involved, neurologic deficits are so common because of the relatively small cross-sectional diameter of the spinal canal relative to the diameter of the cervical cord [1], [4], [5], [6], [7], [8]. One or more of the following may cause the neurologic symptoms: subluxation of vertebrae, impingement of bone, disc, and abscess on the spinal cord or nerve root, local inflammatory response, and tuberculous vasculitis [1], [2], [3], [4], [5], [6], [7], [8], [9], [10], [11], [12], [13]. According to Lubben et al. [12] cervical spine tuberculosis with a cold retropharyngeal abscess is extremely rare. In our patient, tuberculous retropharygeal abscess, osteomyelitis involving multiple vertebrae with the destroyed bony fragments impinging on the spinal cord and intraspinal extension of abscess led to quadriplegia. Besides compressing the cord, this large retropharyngeal abscess resulted in dysphagia and respiratory distress in our patient. According to Hsu and Leong [4], diffuse involvement and the formation of large abscesses is seen mainly in children less than 10 years. Large abscesses may push the trachea onto the sternal notch resulting in respiratory obstruction [4]. Our patient age (13 years), extensive prevertebral abscesses that span from C1-T4 and multiple vertebral bodies’ affectation are in conformity to Hsu and Leong observations. However, we did not find any description of a tuberculous retropharyngeal abscess as extensive as it is in our patient in the literature. Again, cases of cervical TB with quadriplegic complication are very rare in the literature. The only case we found that is similar to ours is the Mpemba Loufoua-Lemay et al. [9] reported case of a recurring quadric paralysis in an 11-year-old girl with cervical, pulmonary and mediastinal tuberculosis. Two other cases with quadriparesis reported by Arumugasamy et al. [6] and Mennonna et al. [7] had complete recovery.
Extensive bony destruction involving multiple vertebrae (C2-T3) and the posterior ribs of the first three vertebrae in our patient is an uncommon finding in tuberculous spondylitis. In cervical tuberculosis, the sixth cervical vertebra is the commonest involved vertebra [1], [5]. However, in many series of spinal TB, most lesions were demonstrated in two or more contiguous vertebral bodies and the vertebral bodies were destroyed in all the patients. The frequent bony destruction is osteolytic in nature [4], [5], [8].
The painless and insidious nature of tuberculous abscess coupled with ignorance might have been responsible for the delayed presentation of our patient until neurological complication, extensive prevertebral abscess and multiple rib and vertebral osteolytic destruction had set in. Poverty is an unlikely contributory factor as parents of this patient were able to afford and carried out all requested investigations promptly.
The initial inability to diagnosed TB and retropharyngeal abscess in this patient are due to inadequate laboratory work up and the absence of non-characteristic abscess features like mottled lucencies or air-fluid levels on the cervical radiograph. Hence, the neck swelling was thought to be lymphadenitis and an initial diagnostic consideration for lymphoma made.
Simple and relatively cheap test as tuberculin skin test (TST) made of purified protein derivative (PPD) has emerged as the definitive means to identify infection with Mycobacterium tuberculosis [14], [15]. TST was the only means of diagnosing latent tuberculosis infection (LTBI) until recently when advances in mycobacterial genomics and human cellular immunology have resulted in new blood tests that detect tuberculosis infection by measuring in vitro T-cell interferon (IFN) release in response to two unique antigens that are highly specific for Mycobacterium tuberculosis [14], [15]. These antigens are absent from bacille Calmette–Guérin (BCG) vaccine and most nontuberculous mycobacteria, which often give in false positive result with TST. The apparent more sensitivity/specificity of the latter in the diagnosis of LTBI according to Lalvani [14] could enable accurate targeting of preventive treatment to patients with infection at the highest risk of progression to active tuberculosis who frequently have false-negative TST results due to impaired cellular immunity. Had either of these tests done in our patient, the diagnosis of TB infection could have been made earlier when therapy would have been beneficial and the catastrophic outcome prevented. Therefore, it is very important to make diagnosis as early as possible before catastrophic complications of tuberculous infection occurs. We advocated the use of easy operating and low-cost examinations such as tuberculin skin test (not done in this patient), abscess puncture (not cut) and pus cultivation especially in developing countries for early diagnosis of tuberculosis infection. Pus culture for mycobacterium often hampered by slow growth requiring about 6 weeks and radiometry method with BACTEC and polymerase chain reaction are other diagnostic laboratory possibilities,
Radiographical findings generally occur late [1], [2], [3], [4], [5]. It is estimated that over 50% of trabecular bone must be destroyed before it becomes evident on radiographs [1], [2]. Radiographical features of TB include narrowing of the intervertebral disc space, adjacent endplate irregularity and erosion, sequestrae and paravertebral masses [1]. The extent of bony involvement was not evident on plain radiograph but at Computed tomography in our patient. Thus, CT is an adequate modality for thorough imaging and diagnosis of TB spine especially in patients with non-specific or ambiguous presentations. It offers a unique opportunity of demonstrating clearly the various component of the spine; it also defines the pattern and extent of the destructive process in our patient. Although not employed in this case, the high contrast and superior soft tissue resolution, and multiplanar capabilities of magnetic resonance imaging (MRI) makes it the modality of choice for evaluating soft tissue extension but for cost. Early in the disease process, MRI has been found to be very sensitive in the detection of marrow changes and intervertebral disc involvement earlier than plain radiographs, CT and bone scintigraphy [2]. MRI is considered to be the most sensitive tool in detecting abnormalities in bone and soft tissue at an early stage especially gadolinium enhanced T1-weighted image [2], [4].
The presentation and outcome of pediatric cervical spine tuberculosis are different from those of adult cervical spine tuberculosis [3], [8], [13]. Cases of tuberculous retropharyngeal abscesses with neurologic complication, neurologic recovery does occur in nearly all the patients following prompt drainage and anti-tuberculous therapy [3], [6]. Treatment of a tuberculous retrpharyngeal abscess by drugs alone is hazardous even in the absence of myelopathy [11]. Although there is no consensus in the literature regarding conservative or surgical management of spinal tuberculosis, some authors [4], [10], [11], [12], [13] opine that surgery should be reserved for selective few where diagnosis is in doubt and there is initial severe or progressive neural deficit with/without respiratory distress in presence of documented mechanical compression and documented dynamic instability following conservative treatment.
Chronic retropharyngeal abscess caused by neglected tuberculosis as in our patient is rare. It should be suspected in a person who presents with a destructive lesion of the vertebra and a retropharyngeal mass. This case has shown that delayed diagnosis and treatment may results in serious complications of the disease.
4. Conclusion
Delayed diagnosis and treatment of cervical spinal TB can be catastrophic. In a child, this could results in extensive prevertebral abscesses, multiple vertebral destruction and quadriplegia. Radiology is essential in its diagnosis. To avoid late diagnosis, it may be necessary to considered TB of the spine in the differential diagnosis of any patient presenting with neck/back pain since it can be successfully treated, especially if detected early. To limit complication, we advocated the use of easy operating and low-cost examinations such as tuberculin skin test, abscess puncture (not cut) and pus cultivation especially in developing countries for early diagnosis TB infection.
References
- . Imaging of tuberculosis of the spine. Singapore Med. J. 2004;45:439–444
- . Imaging in children with spinal tuberculosis: a comparison of radiography, computed tomography and magnetic resonance imaging. J. Bone Joint Surg. 1993;75:233–239
- . Cervical spine tuberculosis in children. Clin. Orthop. Relat. Res. 2007;460:78–85
- . Tuberculosis of the lower cervical spine [C2–C7]: a report on 40 cases. J. Bone Joint Surg. 1984;66B:1–5
- . Computed tomographic evaluation of TB spine in Ibadan. West Afr. J. Med. 2004;23:228–231
- . Tuberculous abscesses of the cervical spine with quadriparesis. Surg. Neurol. 1977;8:35–40
- . One case report of quadriparesis from tuberculous infection of the cervical spine. J. Neurosurg. Sci. 1974;18:278–281
- . Neurological complications of spinal tuberculosis in children. Int. Orthop. 1999;23:210–212
- . Recurrent quadric paralysis in an 11-year-old girl with spinal tuberculosis. Arch. Pediatr. 2007;14:266–269
- . Tuberculous retropharyngeal abscess. Ear Nose Throat J. 2007;86:236–237
- . Tuberculous spondylitis: abscess drainage after failure of anti-tuberculous therapy. Acta Orthop. Belg. 2006;72:337–341
- . Tubercular spondylitis with retropharyngeal abscess. HNO. 2004;52:820–823
- . Tubercular retropharyngeal abscess in early childhood. Indian J. Pediatr. 1997;64:898–901
- . Diagnosing tuberculosis infection in the 21st century. Chest. 2007;131:1898–1906
- . Comparison of tuberculin skin test and new specific blood test in tuberculosis contacts. Am. J. Respir. Crit. Care Med. 2004;170:65–69
PII: S1871-4048(09)00037-9
doi:10.1016/j.pedex.2009.06.003
© 2009 Elsevier Ireland Ltd. All rights reserved.
Volume 5, Issue 3 , Pages 118-120, September 2010
