The document outlines thoracic empyema, defined as pus in the pleural cavity, with common causes including pulmonary tuberculosis and pneumonia. It details the three stages of empyema formation, clinical features, diagnostic investigations, and management objectives which include controlling infection and draining purulent fluids. Additionally, the document describes various types of abscesses, their causes, symptoms, and management strategies.

1. Thoracic Empyema and
Abscesses
DR.MAGONYA

2. Learning objectives
By the end of this session, students are expected to be able to:
• Define thoracic empyema and abscess
• Describe causes and pathophysiology of thoracic empyema
• Describe clinical presentation of thoracic empyema
• Identify relevant investigations for thoracic empyema
• Describe management of thoracic empyema and abscesses

3. Introduction
Thoracic empyema: The presence of pus in the pleural cavity.
Causes
• Pulmonary tuberculosis (PTB) is the most common cause in Tanzania
• Postpneumonic or parapneumonic
• Lung abscess
• Thoracic trauma
• Gastrointestinal tract (from oesophagus or through diaphragm)
• Extension of a non-pleural-based infection (e.g. mediastinitis)

4. • Instrumentation of the pleural space, such as in thoracentesis, or tube
thoracostomy
• Subdiaphragmatic abscess
• Thoracic vertebral osteomyelitis
• Retropharyngeal abscess

5. Pathophysiology
• An empyema is either acute or chronic
• The formation of an empyema has 3 stages:
oExudative stage: Protein-rich pleural fluid remains free-flowing.
 The number of neutrophils is rapidly increasing.
 Glucose and pH levels are normal.
 Drainage of the effusion and appropriate antimicrobial therapy are
normally sufficient for treatment.

6. oFibrinolytic stage: Viscosity of the pleural fluid is increasing.
 Coagulation factors are activated, and fibroblast activity begins
coating the pleural membrane with an adhesive meshwork.
 Glucose and pH levels are lower than normal.

7. • Organizing stage: Loculations are forming.
 Fibroblast activity causes adherence to the visceral and parietal
pleura.
 This activity may progress with the formation of pleural peels in which
the pleural layers are indistinguishable.
 Pus, which is a protein-rich fluid with inflammatory cells and debris, is
present in the pleural space.
 Surgical intervention is often required at this stage.

8. Clinical features
The patient's history may reveal the following findings:
• Recent diagnosis and treatment for pneumonia
• Recent history of penetrating chest trauma
• Cough productive of bloody sputum that frequently has a fetid odour
or offensive smell
• High-grade fever

9. • Shortness of breath
• Anorexia and weight loss
• Night sweats
• Pleuritic chest pain during early stages
• Malaise

10. Physical examination may reveal the following findings:
• Temperature frequently elevated
• Tachypnea
• Rales/crepitations
• Rhonchi
• Tubular breath sounds
• Decreased breath sounds
• Decreased fremitus
• Stony dullness to percussion

11. Investigation
• Chest X- ray may reveal:
oUnderlying disease (e.g. pneumonia, lung abscess)
oPleural fluid
• Pleural aspiration; appearance is turbid or purulent fluid
• Sputum gram staining ± culturing and sensitivity testing
• Full blood count

12. Differential Diagnosis
• Pleural effusion
• Pneumonia
• Tuberculosis
• Pulmonary abscess

13. Management of Thoracic Empyema
Objectives of Treatment
• Control infection
oParenteral antibiotics are prescribed to control the infection
oAnti TB if indicated
• Drain the purulent fluid
oInsert a chest tube to completely drain the pus.
• Eradicate the sac to prevent chronicity and allow re-expansion of the
affected lung to restore function.

14. Note: Remember drainage of the purulent fluid and eradication of the
sac (objectives 2 and 3) should be done in a district/regional specialized
hospital.

15. Abscesses
Abscess: A localized collection of pus contained within a cavity that is
formed after tissue destruction; the cavity is surrounded by a pyrogenic
membrane.

16. Types of Abscesses
• Breast abscess
oBreast infections, common during lactation, are most often caused by
Staphylococcus aureus.
oThe bacteria gain entrance through a cracked nipple causing mastitis
(breast cellulitis) which may progress to abscess formation.
oThe features of a breast abscess are pain, tender swelling and fever,
the skin becomes shiny and tight but, in the early stages, fluctuation is
unusual.

17. oFailure of mastitis to respond to antibiotics suggests abscess
formation even in the absence of fluctuation or an infection caused by
bacteria not covered by the antibiotic(s) being administered (such as
Methicillin-Resistant Staphylococcus aureus, or MRSA).
oWhen in doubt about the diagnosis, perform a needle aspiration to
confirm the presence of pus.
oThe differential diagnosis of mastitis includes the rare but aggressive
inflammatory carcinoma of the breast (inflammatory carcinomatosis).
oSuccessful drainage of a breast abscess requires adequate
anaesthesia.

18. • Pelvic abscess
oPelvic abscesses occur secondary to the same conditions that cause
intra-peritoneal abscesses if the pus and fluid tracks downwards into
the pelvis. In addition, gynaecological infections can cause pelvic
abscesses.
oPelvic abscesses can cause symptoms of frequent urination, diarrhoea
or tenesmus (a sensation of incomplete bowel emptying).
oIf symptoms are mild, pelvic abscesses do not require surgical
treatment as they often respond to systemic antibiotics.

19. • Sub-phrenic abscess
oThis is a collection of pus below the diaphragm (the muscular organ
separating the abdominal cavity from the chest cavity).
oIt is often caused by rupture of the gallbladder, generalised peritonitis
or post-abdominal operations that causes fluid to build up under the
diaphragm.
oAbscesses in this location are close to the lungs so they can cause
basal lung infections. Symptoms may mimic pneumonia.

20. • Intra-peritoneal abscess
oThis is an abscess within the peritoneal cavity due to an infection of
free fluid, bile or blood.
oOften these abscesses are the result of bowel perforation or a
complication of bowel surgery.
oSpillage of feacal material from an inflamed appendix frequently
causes this type of abscess.

21. • Visceral abscess
oAbscesses are also found on the surface or within gastrointestinal organs.
oLiver abscesses are the most common and account for approximately half of all
visceral abscesses. These may cause pain in the right upper part of the abdomen.
oPancreatic abscesses occur as a late complication of acute pancreatitis.
Pancreatitis causes severe central abdominal pain that spreads to the back.
oEarly recognition and treatment of this disorder will prevent abscesses
formation.
oAbscesses of the spleen are rare but can occur if this organ is damaged or if
there is an infection in the blood.

22. Psoas abscess
• The psoas muscle is a large muscle running alongside the spine which
crosses the pelvis.
• Clinical signs are back pain or pain during flexion of the hip.
• Abscesses occur in the psoas muscle when infections spread in the
blood or from local organs of the abdomen or pelvis.
• In addition, infections in the bones of the spine (osteomyelitis) can
cause psoas abscesses.

23. Anorectal abscess
• The anus and rectum are other common sites of abscess formation worth
separate mention.
• Anorectal abscesses are more common in men and often develop into
anorectal fistulas.
• They usually result from minor trauma in the perineum and anorectal
area.
• They present as painful, tender swellings and are easily accessible by
surgical treatment.

24. Summary
• Thoracic empyema is the presence of pus in the pleural cavity.
• PTB and pneumonia are common causes of empyema in our settings.
• The formation of an empyema has 3 stages:
oExudative stage
oFibrinolytic stage
oOrganizing stage

25. • The objectives of treatment are to control infection, drain the
purulent fluid and eradicate the sac.
• An abscess is a localized collection of pus contained within a cavity
formed by destruction of tissue.
• There are different types of abscesses such as breast abscess, pelvic
abscess, sub-phrenic abscess, intra-peritoneal abscess, visceral
abscess, psoas abscess and anorectal abscess.