This document discusses cold abscesses, which are collections of pus that develop as a result of tuberculosis infection elsewhere in the body, most commonly the lymph nodes or bones. Cold abscesses are called such because they do not present with the typical signs of inflammation. The document outlines the pathogenesis of cold abscesses, their typical locations, clinical features, diagnostic testing including imaging and labs, and treatment approaches including anti-tubercular medications, aspiration or surgical drainage.

1. COLD ABSCESS
Dr. P.Sudheer kumar
Orthopaedics postgraduate
Narayana medical college & hospital

2. Introduction
 An Abscess is a collection of pus within the
body.
 It is cold because it is not accompanied by the
classical signs of inflammation
 Almost always a sequel of tubercular
infection anywhere in the body commonly in
the lymph nodes & bone.

3. Pathogenesis
 Any osteoarticular tubercular lesion is a result
of a hematogenous dissemination from a
primarily infected visceral focus
 Primary focus may be in Lungs,lymph glands
of mediastinum/mesentry/cervical region or
kidneys or other viscera.
 Phagocytosis of tubercle bacilli by RES

4. Pathogenesis
 The characteristic microscopic lesion is the
tuberculous granuloma– a collection of
epithelioid and multinucleated giant cells
periphery.
 Within the tubercle, small patches of caseous
necrosis appear. These may coalesce into a
larger yellowish mass, or the centre may break
down to form an Abscess.

5. Pathogenesis
Polymorpho
nuclear cells
Langhans
giant cells
Macrophages
& monocytes
Central
caseation
necrosis
Epitheliod cells
Cold
abscess

6. Histology

7. Pathology
 It is formed by collection of products of
liquefaction & the reactive exudation
 It penetrates the ligaments in articular
disease, bone & periosteum in osseous disease
 Migrates in various directions following the path
of least resistance along fascial planes,blood
vessels and nerves, to distant sites

8. Composition
 Mostly composed of





-serum
-leucocytes
-caseous material
-bone debris
-tubercle bacilli

9. Sites
 Commonly at Neck &
Axilla
 Also at Groin,back,side
of chest wall
 These are sequel of
tubercular infection of
spine,ribs & posterior
medistinal group of
lymph nodes.

10. Clinical features
 Painless Swelling
-insidious onset
-soft & smooth mass
-cystic consistency
-fluctuation present
-slip sign negative
-No transillumination

11. Clinical features…
 Sinus or ulcer
 superadded infection with pyogenic organisms
 Constitutional symptoms like low grade
fever, cough , weight loss,loss of appetite
 Symptoms of primary tuberculosis

12. Clinical features…
 Local Pressure effects due to swelling
c-spine: exudate collects behind prevertebral
fascia & protrude as retropharyngeal abscess
causing dysphagia, dysphonea, hoarseness of voice
& respiratory obstruction
 abscess may track down to enter
trachea, esophagus or pleural cavity. It may spread
laterally into the sternomastoid muscle & forms an
abscess in the neck.

13. Clinical features…
 T-spine: exudate 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.

14. Clinical features…
 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
it.(pseudo hip flexion)
 Can gravitate beneath inguinal ligament to appear
on the medial aspect of thigh
 exudate can follow vessels to form an abscess in
scarpa’s triangle or gluteal region

15. Differential diagnosis
 Pyogenic abscess
 Lipoma
 cyst
 Soft tumors

16. Investigations
 Lab studies
 Microbiology studies to confirm
diagnosis
 Radiological diagnosis

17. Lab studies
 Mantoux / Tuberculin skin test
 ESR may be markedly elevated (neither
specific nor reliable).
 ELISA : for antibody to mycobacterial antigen-
6 , sensitivity of 60% – 80%.
 PCR

18. Fnac & Biopsy
 Percutaneous , CT scan ̶ guided needle biopsy
of bone lesions is a safe procedure that also
allows therapeutic drainage of large
paraspinal abscesses
 Biopsy is confirmative

19. 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 50% of cases.

20. Radiological diagnosis
1. PLAIN RADIOGRAPH
2.ULTRASOUND
3. CT SCAN
4. MRI SPINE
5.BONE SCAN

21. Plain Radiograph
 Cervical region
- b/w vertebral bodies , pharynx and trachea
 Upper thoracic
- ‘V’ shaped shadow , stripping lung apices laterally
and downwards
 Below T4 – fusiform shape (bird nest appearence)
 Below diaphragm – unilateral / bilateral psoas
shadow

22. Plain Radiograph…

23. ULTRASOUND
Detect cold abscess
A HYPO ECHOEIC LESION
Internal echoes represent debris within.
Guided aspiration

24. CT IMAGE
Patterns of bony destruction.
Calcifications in abscess (pathognomic for Tb)

25. MRI
•Assessment of extradural abscesses / subligamentous spread.
•Skip lesions
•Spinal cord involvement.

26. Radionucleotide Scan T 99m
 Increased uptake in up to 60 per cent patients
with active 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

27. TREATMENT
 Anti tubercular drugs
 Aspiration
 Ultrasound guided Pigtail catheter drainage
 Surgical management

28. ANTI TUBERCULAR DRUGS
 Same as tuberculosis elsewhere in the body.
 The chemotherapy is continued for 18 months.

Drug:
Dosage:
Side effects:

Rifampicin:
450-600mg
Liver toxicity

Isoniazid
300-450mg

Pyrizanamide:
40mgms/kg
peripheral neuritis
Liver toxicity.
hyperuricemia

Ethambutol:
15-25mgms/kg.

Streptomycin(inj)
20mgms/kg
Optic neuritis.
vestibular damage,
nephrotoxicity

29. 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

30. Ultrasound guided Pigtail catheter
drainage

31. 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
 Correcting underlying bony lesion/defect.