1) Cold abscesses are collections of pus that develop slowly without signs of inflammation and are usually caused by tuberculosis infection elsewhere in the body, commonly the lymph nodes or bones.
2) They form via a pathological process where the tuberculosis bacteria are phagocytosed by immune cells, forming granulomas with caseous necrosis that can break down and track along tissue planes, appearing as painless swellings distant from the original infection site.
3) Diagnosis involves tuberculin skin testing, biopsy or aspiration of the abscess, and radiological imaging like ultrasound or CT scan may help locate the abscess. Treatment consists of anti-tuberculosis drugs alongside drainage of palpable abscesses.
3. Introduction
• An Abscess is a collection of liquefied tissue(pus) in the
body, which is body’s defense reaction to foreign
material.
• Cold abscess comes from the Gothic word "kalds"
meaning "cold" and the Latin word “abscessus” meaning
“ going away.”
• together means “ going away cold.”
4. • It is called cold abscess because it is not accompanied by
the classical signs of inflammation- heat, redness, fever,
pain etc., which are usually found with pyogenic abscess.
• More commonly, a sequelae of tubercular infection
elsewhere in the body commonly in the lymph nodes &
bone.
5. OTHER CAUSES
• Actinomycosis
• Leprosy
• Fungal infections like Blastomycosis
• Hyperimmunoglobulin E syndrome (job’s syndrome)
-recurrent staphylococcal cold abscess
-eczema
-increased Ig E
6. Pathogenesis
• Any osteoarticular tubercular lesion is result of a
hematogenous dissemination from a primarily infected
visceral focus
• Primary focus may be in Lungs, lymph nodes of cervical
region/mediastinum/mesentery, kidneys or other viscera.
• Phagocytosis of tubercle bacilli by RES
7. • The characteristic microscopic lesion is the tuberculous
granuloma– a collection of epithelioid and multinucleated
giant cells in the periphery.
• Within the tubercle, small patches of caseous necrosis
appear. These may coalesce into a larger yellowish mass and
the centre may break down to form an Abscess.
10. FROM VERTEBRAL TB
• It develops as an exudative lesion due to hypersensitivity
reaction to mycobacterium tuberculosis.
• It is formed by collection of products of liquefaction & the
reactive exudation
• It penetrates the ligaments in articular disease, bone &
periosteum in osseous disease
11. • Migrates in various directions following the path of least
resistance along fascial planes, blood vessels and nerves to
appear superficially at distant sites away from the site of
lesion.
• Spinal TB presents more commonly as
- clinical kyphosis 95%
- palpable cold abscess 20%
- radiological paravertebral abscess 21%
- tubercular sinuses (active/healed) 13%
12.
13. FROM TB LYMPHADENITIS
• In the initial stages, the nodes may be discrete.
• Periadenitis results in matting and fixity of lymph nodes.
• The lymph nodes coalesce and breakdown to form caseous
pus which may perforate the deep fascia and present as
fluctuant swelling on the surface.
14. • The overlying skin becomes indurated, breaks down and
leads to the formation of a sinus.
• Healing occurs with calcification and scarring.
• Without treatment, it may remain unhealed for years.
18. Sites
• Commonly at Neck & Axilla
• Also at loin, back, side of chest
wall
• These are sequelae of tubercular
infection of spine,ribs &
posterior medistinal group of
lymph nodes.
21. Clinical features…
• Sinus or ulcer
• superadded infection with pyogenic organisms
• Constitutional symptoms like low grade fever,
cough , loss of weight & loss of appetite
• Symptoms of primary tuberculosis
22. Local Pressure effects due to swelling
c-spine:
the exudate collects behind prevertebral fascia &
protrude forward as retropharyngeal abscess causing
-dysphagia,
-dysphonea,
-dyspnoea,
-hoarseness of voice
23. •The abscess may track down in mediastinum to
enter trachea, esophagus or pleural cavity. It may
spread laterally into the sternomastoid muscle &
forms an abscess in the neck.
24. T-spine:
• The exudate may be confined locally as paravertebral
abscess
• it may enter into spinal canal & compress spinal cord
leading to Early onset pott’s paraplegia
• it can penetrate anterior longitudinal ligament to
form mediastinal abscess .
• pass downwards through medial arcute ligament to
form a lumbar abscess.
25. •Rarely, the thoracic cold abscess may follow the
intercostal nerve to appear anywhere along the
course of nerve.
26. Granuloma formation
Tissue necrosis &
inflammatory response
Paraspinal Abscess
LocalizedTrack along tissue
planes
Progressive necrosis of
vertebral body-Kyphotic
deformity
Adjacent vertebral
bodies under the
longitudinal ligaments
Along the fascial planes Ex:
Psoas abscess
PARAVERTEBRAL ABSCESS
27. Lumbar spine:
• abscess can have pus track along the psoas muscle towards
the groin & presents as psoas abscess
• Flexion deformity of hip can develop due to the
abscess(pseudo flexion deformity of hip)
• Can gravitate beneath the inguinal ligament to appear on the
medial aspect of thigh
28. • It can spread laterally beneath iliac fossa to emerge at the
iliac crest near the anterior superior iliac spine.
• The exudate can follow vessels to form an abscess in scarpa’s
triangle or gluteal region.
32. Lab studies
• Mantoux / Tuberculin skin test
• ESR may be markedly elevated (neither specific nor
reliable).
• ELISA : for antibody to mycobacterial antigen.
sensitivity of 60% – 80%.
• PCR assays
33. FNAC & BIOPSY
• Percutaneous CT ̶ guided needle biopsy of bone lesions is a
safe procedure that also allows therapeutic drainage of large
paraspinal abscesses
• Biopsy is confirmative
34. Microbiology studies to confirm
diagnosis
• Ziehl-Neelsen staining: Quick and inexpensive method.
• Bone tissue or abscess samples stain for acid-fast
bacilli (AFB), & isolate organisms for culture & drug
susceptibility.
• Culture results - few weeks.
• Positive only in 60% of cases.
36. PLAIN RADIOGRAPH
• Cervical region
- retropharyngeal abscess
may be seen on lateral x-ray.
-soft tissue shadow thickness
in front of C3 vertebra >4mm
indicates retropharyngeal
abscess.
37. •Thoracic region
- A paravertebral shadow on AP view indicates paravertebral
abscess.
it may be of
-fusiform shape (bird nest abscess) – length > width
-globular or tense abscess – width > length
46. Radionucleotide Scan Tc 99m
• Increased uptake in upto 60 percent patients with active bone
tuberculosis.
• Avascular segments and abscesses show a cold spot due to
decreased uptake.
• Highly sensitive but nonspecific.
• Aid to localise the site of active disease and to detect multilevel
involvement
48. ANTI TUBERCULAR DRUGS
-Treatment is same as TB elsewhere in the body.
-With anti tubercular drug therapy, small cold abscesses
heal along with bone/lymphnode tb.
49. Aspiration
•Palpable Cold abscess must be drained as early as
possible & instil 1gm Streptomycin +/- INH in solution
•Technique: Zig-Zag aspiration using Wide bore needle
from non-dependent area to prevent sinus formation
51. Surgical
• Open drainage may be performed if aspiration failed to clear
it.
• Drainage using non-dependent incision,later closure of
wound without placing a drain to prevent sinus formation.
• Correcting underlying bony lesion/defect.
52. • Cold abscess of chest wall sometimes may
require rib resection, clavicle and sternum
resection along with abscess excision.
66. NEXT SEMINAR ON WEDNESDAY
16-09-2015
MONTOUX TEST
BY DR.KALYAN
Notas do Editor
1.Commonest site for tuberculosis
2. Thoracic kyphosis helps in squeezing the
products into the canal
3. Cord : canal ratio is smaller
4. Spinal cord terminates below L1
5. Ant. Lon. Lig. Is loose in thoracic spine
whereas in lumbar pus enters the psoas