TB pleural effusion

林倬睿醫師

Outlines • Introduction• Etiology & pathogenesis• Symptoms, laboratory & radiologic

findings • Diagnosis• Treatment & management• Complications

Introduction

• 是由結核菌感染肋膜所引起• 通常為 exudate, 可以同時合併肺部病灶• 為最常見的肺外結核表現• HIV患者若 CD4數目較高 , 則 TB pleural

effusion發生率較高 ,可見 TB pleural effusion的形成不只是感染 ,更是一種免疫反應 (immunological response)

Etiology & pathogenesis• Mycobacterial protein access pleural

cavity through a rupture of a subpleural focus

• TB protein mesothelial/endothelial cells cytokines neutrophils, lymphocytes, monocytes, etc

• Pleural fluid: neutrophil in the early phase, highly suggestive of TB if lymphocyte > 85%

Mycobacteria liposaccharides

Mesothelial / endothelial cells

IL-1, IL-6, TNF- α chemokines-α chemokines-

IL-8, NAP2 MIP-1, MCP-1, TNF- α

Neutrophil, lymphocyte

Activated lymphocyte

Th1

IL-12, IFN-ɤ

IL-1, TNF- α

Mesothelial cell

Monocyte- macrophage Mycobacteria

ADA1

ADA2-ADA1

• HIV pt 因免疫反應差 , 在 effusion中較常發現 TB 菌 ,biopsy中則較少見granuloma

• Effusion的形成雖與免疫反應有關 ,但得到 TB pleurisy不表示就因此產生抵抗力 ,若未治療 ,即使自然痊癒 ,將來仍有超過65%會發生 active pulmonary TB

• TB可以躲在macrophage中

Etiology & pathogenesis

Symptoms • Male : female = 3 : 1• Mostly < 35y/o or > 70y/o• Acute or subacute onset• S/S to diagnosis: < 1month• Cough, fever, chest pain, dyspnea• HIV pt: hepatosplenomegaly, LAP, less

PPD (+)

Laboratory findings

• Non-specific (ESR , normal WBC)

• Pleural effusion:– color : serofibrinous, serosanguinous– exudate– lymphocyte predominant– exclude TB, if : eosinophil > 10%

mesothelial cell > 5%

Radiological findings

• Usually unilateral, small to moderate in size

• 30% 的病人在同側肺實質有radiological disease

• HIV pt 的 effusion量較多 ,雙側有水的機會也比一般人高

• Primary: lower lobe involvement & LAP

Diagnosis

• Presumption: prevalence, HIV co-infection, pleural effusion, clinical symptoms

• Definite diagnosis: – M. TB in sputum or effusion– caseous granulomas in the pleura

(A) P.E. with atelectasis

(B) anechoic (C) complex nonseptated

(D) complex septated

(E) homogenously echogenic

(F) parapneumonic effusion

(G) malignant effusion

Granuloma of Tuberculosis

• Positive sputum culture rate:– 30–50% in pleural + lung involvement– only 4% in pleural involvement alone

• Diagnostic methods:– pleural effusion culture: 23-86%– biopsy culture: 39-71%– presence of necrotizing caseous granuloma

in biopsy: most efficient, 51-87%– all combined: 82-98%

Diagnosis

Diagnosis

• Among HIV pt:

– more positive sputum culture

– more AFB (+) in pleural effusion

– more positive biopsy culture

– less granuloma formation

Diagnosis • Conventional method: pleural biopsy• New methods:

– finding TB: radiometric culture system,

PCR– measure parameters caused by

immunological-metabolic mechanism:

adenosine deaminase (ADA), IFN-ɤ, etc

Diagnosis

• Radiometric culture system:– accelerate diagnosis by 2-3 weeks

• PCR– rapid– identify the type of mycobacteria– determine susceptibility to drugs– not that reliable, requires QC procedure

• ADA (adenosine deaminase)– Pleural TB infection increased metabolic

activity of the monocytes & macrophages increased production of ADA

– High levels of ADA: TB pleurisy, empyema, malignant lymphoma, collagen-vascular disease

– Sensitivity: 77-100%, specificity: 81-97%

Diagnosis

• ADA (adenosine deaminase)– Association with L/N ratio > 0.75 or <

35y/o greatly improves the specificity– No differences with regard to HIV status– May be a better negative predictive

parameter– ADA1: ubiquitous– ADA2: only in monocytes, macrophages

Diagnosis

• IFN-ɤ– relative good sensitivity & specificity– False positive: parapneumonic effusion,

lymphoma, malignancy– Disadvantage: expensive, slow

• Others – Lysozyme, tuberculostearic acid,

monoclonal antibody, cytokines

Diagnosis

Treatment

• Spontaneous resolution in 2-4 months in healthy individuals

• 65% will develop pulmonary tuberculosis in 5 years

• So, it is important to treat pleural tuberculosis

• Should be monitored by official public health center– Ensure correct treatment– Prevent the emergence of resistant strain– Evaluation of contacts– Monitor the pattern of resistances – Provide education to the patients– Identify possible outbreaks

Treatment

• As pulmonary TB, combination therapy is preferred– Reducing the population of mycobacteria– Without creating resistance– Sterilizing the lesions during prolonged

treatment phase

Treatment

• Duration: 6 month is recommended• Number of drugs: HRZ for 2 months,

then HR for 4 months. • Add EMB if

– Local resistance to INAH > 4%– High levels of resistance are reported– Received anti-TB drug previously– Exposed to MDR-TB patients

Treatment

• Some may show an increase of pleural effusion during the initial phase

• Standard treatment is recommended for HIV patients.

• If the clinical or bacteriological response is slow or less than optimal prolong treatment

Treatment

• Use of steroid

– Insufficient evidence to prove that steroid

can reduce inflammation and subsequent

residual pachypleuritis–不如在診斷性抽水時把水抽乾一點

Treatment

Complications

• Residual pleural thickening

– Most frequent

– Incidence varies according to the time of

evaluation and the degree of thickness

– No variable idetified

– Minimal impact on lung functions

• Tuberculous empyema– Unusual, normally related to BP fistula– Response to medical treatment is limited– Frequently requires thoracotomy and/or

decortication– May consider repeated thoracentesis with

prolonged medical treatment

• Thoracic wall infection– Rare, 1/106

Complications

Thanks for your attention!