Download Clinical Aspects of Tuberculosis

Clinical Aspects of
Tuberculosis
Professor Mike McKendrick
Lead Physician
Department of Infection and Tropical Medicine
Royal Hallamshire Hospital
Sheffield
Honorary Professor
Division of Genomic Medicine
University of Sheffield
Dpt. Infection and Tropical Medicine,
Sheffield Teaching Hospitals
Clinical aspects of TB

Pathogenisis
 Clinical diagnosis
 Treatment and monitoring and control
 New issues
Dpt. Infection and Tropical Medicine,
Sheffield Teaching Hospitals
Clinical Aspects of
Tuberculosis

Pathogenesis of tuberculosis
– Infection versus disease
 Host factors
 Pathogen factors
Dpt. Infection and Tropical Medicine,
Sheffield Teaching Hospitals
Pathogenesis

Host factors include
– Social e.g.


Poverty
alcoholism
– Age e.g.



Baby
Teenage girl
Old age
– Immunity e.g.



HIV
Gamma interferon
SCID
Dpt. Infection and Tropical Medicine,
Sheffield Teaching Hospitals
Pathogenesis

Organism factors e.g.
– Virulence factors
– [Drug resistance]
Dpt. Infection and Tropical Medicine,
Sheffield Teaching Hospitals
Pathogenesis


MTB into lungs (or to cervical nodes or abdo. nodes)
Replication of organisms
Primary complex (lung and mediastinal lymph nodes)

Mycobacteraemia with potential for ‘seeding’

Consequence of tuberculous infection

– Symptomatic illness – disease (minority)
– immunological control (majority) with Ghon focus on Xray.
Infection is ‘contained’ by granuloma but not eliminated
Dpt. Infection and Tropical Medicine,
Sheffield Teaching Hospitals
Pathogenesis

Tuberculous disease is a consequence of:
– Primary infection e.g. in baby
– Reactivation


‘natural’
Associated with immunosupression
– Re infection
Dpt. Infection and Tropical Medicine,
Sheffield Teaching Hospitals
Clinical features
 Clinical
illness
– Pulmonary
– Extrapulmonary
Dpt. Infection and Tropical Medicine,
Sheffield Teaching Hospitals
Clinical illness

Chest
–
–
–
–

Pulmonary
Pleural
Mediastinal nodes
pericardium
Extra pulmonary
–
–
–
–
–
skin and soft tissues (including lymph nodes)
Bone
Abdominal
Intra cranial
other
Dpt. Infection and Tropical Medicine,
Sheffield Teaching Hospitals
Clinical clues for TB

Clinical symptoms – usually ‘chronic’ rather than acute
–
–
–
–
Fever
Sweats
Weight loss
Focal symptoms
 Epidemiology
– History of TB, HIV
– Country of origin, recent travel/work
– Contact with TB
[England, Wales & NI 2004


7,176 notifications, 414 children
70% foreign born population groups]
Dpt. Infection and Tropical Medicine,
Sheffield Teaching Hospitals
TB – guidelines for the clinician

Great mimicker
 Low index of suspicion
 Pulmonary TB usually easy to consider
 Non pulmonary often requires ‘lateral
thinking’
Dpt. Infection and Tropical Medicine,
Sheffield Teaching Hospitals
Clinical TB

Laboratory samples
– In the current era every effort must be made to
obtain adequate samples likely to lead to a
microbiological diagnosis before treatment is
started (sometimes difficult with surgical
specimens!)
Dpt. Infection and Tropical Medicine,
Sheffield Teaching Hospitals
What can the laboratory do to
help the clinician?

Awareness of TB e.g. in the patient with recurrent
sputum samples for ‘chronic bronchitis’

‘Rapid’ diagnosis of infection and resistance
– Culture and sensitivities – the clinician wants answers
immediately if possible
– PCR – further opportunities for development
– Gamma interferon based tests??
– other
Dpt. Infection and Tropical Medicine,
Sheffield Teaching Hospitals
What samples? Depends on clinical
scenario

Chest
–
–
–
–
–

Sputum – if productive
Induced sputum
Bronchoscopic alveolar lavage (BAL)
Pleural biopsy
Pleural fluid
Other
– E.g. Lymph node, aspiration of abscess, mesenteric
biopsy, stool, bone marrow etc.
– What about EMSU? - should be done selectively where
it is likely to be helpful
Dpt. Infection and Tropical Medicine,
Sheffield Teaching Hospitals
Induced sputum

Hypertonic saline nebuliser in negative
pressure room with HEPA filter and well
trained physiotherapist
– Study of 27 confirmed positive patients
 13 +ve induced sputum only
 1 +ve bronchoscopy only
 13 +ve induced sputum and bronchoscopy
McWilliams T et al Thorax 2002: 57; 1010-1014
Dpt. Infection and Tropical Medicine,
Sheffield Teaching Hospitals
Audit of induced sputum in
Department of Infection in Sheffield
– Criteria for procedure
– Past history TB or contact with TB in last year
– Respiratory symptoms of one or more of:
• Non-productive cough
• Fever, Night sweats, weight loss
• Haemoptysis
114 procedures, 12 positive for TB
– Cohort followed up for 12 months, no cases
missed
- Bell et al. J Infection 2003: 47; 317-321
Dpt. Infection and Tropical Medicine,
Sheffield Teaching Hospitals
Clinical cases

Cases of
– pulmonary infection
– Non pulmonary infection
– Examples of spectrum of disease produced by
TB
Dpt. Infection and Tropical Medicine,
Sheffield Teaching Hospitals
Pulmonary and non pulmonary
TB disease – Sheffield 2005

Equal numbers of patients with pulmonary
and non pulmonary tuberculosis
Dpt. Infection and Tropical Medicine,
Sheffield Teaching Hospitals
Clinical presentation 1

35 year old African lady with fever and dry
cough for 3 weeks.
 Mildly unwell
 Night sweats
 Weight loss 4 pounds
 No history of contact with TB
 CXR
Dpt. Infection and Tropical Medicine,
Sheffield Teaching Hospitals
Case 1 – miliary tuberculosis
Dpt. Infection and Tropical Medicine,
Sheffield Teaching Hospitals
Pulmonary TB typically affects
the upper zones of the lung
Dpt. Infection and Tropical Medicine,
Sheffield Teaching Hospitals
Case 1

Investigation
– FBC normal
– ESR 53
– U and E normal
– LFT – albumen 31
– CRP 40
– Induced sputum – smear negative
Dpt. Infection and Tropical Medicine,
Sheffield Teaching Hospitals
Case 1

Progress
– Clinical diagnosis of TB
 4 drug treatment
 Clinical improvement
– TB culture
 positive at week 3
 fully sensitive (week 5)
 Modified anti TB drug regime in light of lab results
Dpt. Infection and Tropical Medicine,
Sheffield Teaching Hospitals
Case 1

What about HIV testing? – who to test?
– Strong association between HIV and TB
– Universal testing or selective testing?

What about testing for vitamin D?
– Vitamin D has role in activating macrophages to
destroy mycobacteria
– Vitamin D deficiency in ethnic populations in UK often
low
Dpt. Infection and Tropical Medicine,
Sheffield Teaching Hospitals
Case 1

Cured after standard 6 months therapy
Dpt. Infection and Tropical Medicine,
Sheffield Teaching Hospitals
Clinical presentation 2

28 year old African lady with backache for
6 weeks
 Diagnosed initially as non specific
 Developed fever – no obvious cause
 ID opinion sought
 Investigation with MRI scan
Dpt. Infection and Tropical Medicine,
Sheffield Teaching Hospitals
Clinical case 2

Diagnosis
– Vertebral osteomyelitis with soft tissue mass
impinging on the cord

Investigation


Biopsy and culture
Treatment
– 4 anti TB drugs and antibiotic therapy
Dpt. Infection and Tropical Medicine,
Sheffield Teaching Hospitals
Clinical case 2
What will happen if diagnosis or
treatment for TB spinal
osteomyelitis is delayed?
Dpt. Infection and Tropical Medicine,
Sheffield Teaching Hospitals
What will happen if treatment delayed? – gibbus
formation (acute angulation of spine with or
without neurological damage)
Dpt. Infection and Tropical Medicine,
Sheffield Teaching Hospitals
The physical appearance – Potts
disease of spine - gibbus
Dpt. Infection and Tropical Medicine,
Sheffield Teaching Hospitals
Clinical case 2

Progress
– Increasing back pain and neurological
symptoms – mild leg weakness
– Repeat MRI – changes similar

Treatment
– Continue therapy
– consider surgical decompression
Dpt. Infection and Tropical Medicine,
Sheffield Teaching Hospitals
Clinical case 2

Further progress



Other considerations - clinical



Weakness of legs
Neurosurgery and internal splinting
Has she got HIV?
Is her vitamin D level normal?
Other considerations - epidemiological


From where has she got infection?
To whom might she have given it?
Dpt. Infection and Tropical Medicine,
Sheffield Teaching Hospitals

TB may affect any tissue of the body
including:
–
–
–
–
Skin and soft tissue
Lymph nodes
Bones and joints
Intra abdominal structures including




peritoneum
Kidneys
Adrenal glands
Lymph nodes
– Central nervous system
 Tuberculoma
 meningitis Dpt. Infection and Tropical Medicine,
Sheffield Teaching Hospitals
Skin and soft tissue
Dpt. Infection and Tropical Medicine,
Sheffield Teaching Hospitals
25 male African. Expanding non painful lesion in
neck - Cervical lymph node TB progressing to
abscess (beware deep extension – collar stud
abscess)
Dpt. Infection and Tropical Medicine,
Sheffield Teaching Hospitals
TB node in neck with deep
extension
Dpt. Infection and Tropical Medicine,
Sheffield Teaching Hospitals
35 female African – systemically well - hand and
foot lesions present for 6 months – MTB grown on
biopsy by plastic surgeons (HIV neg)
Dpt. Infection and Tropical Medicine,
Sheffield Teaching Hospitals
Bony tuberculosis
Dpt. Infection and Tropical Medicine,
Sheffield Teaching Hospitals
Astute radiologist should enable the
appropriate further investigation
Dpt. Infection and Tropical Medicine,
Sheffield Teaching Hospitals
Often associated with delay in diagnosis –
any chronic discharging lesion must be
considered possibly TB
Dpt. Infection and Tropical Medicine,
Sheffield Teaching Hospitals
Abdominal Tuberculosis
Dpt. Infection and Tropical Medicine,
Sheffield Teaching Hospitals
Renal tuberculosis (may have few
or no symptoms) leading to
autonephrectomy
Dpt. Infection and Tropical Medicine,
Sheffield Teaching Hospitals
30 middle eastern asylum seeker - abdo pain,
fever, sweats – CT scan - peritoneal TB
confirmed on biopsy – may mimic malignancy
Dpt. Infection and Tropical Medicine,
Sheffield Teaching Hospitals
Intracranial TB
Dpt. Infection and Tropical Medicine,
Sheffield Teaching Hospitals
miliary TB on MRI scan
tuberclomas on CT scan
Dpt. Infection and Tropical Medicine,
Sheffield Teaching Hospitals
meningitis – diagnosis usually made on
clinical grounds

Clinical
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Acute or subacute
Prognosis related to severity of disease at onset of treatment
Commonly delay between presentation and diagnosis
Common in children
c100 cases per year in England
CSF
–
–
–
–
Cell count 50-500 (50% lymphs, 50% polys)
High protein ++
Low glucose
Micro often negative (PCR/culture important)
Dpt. Infection and Tropical Medicine,
Sheffield Teaching Hospitals
Treatment of TB
Dpt. Infection and Tropical Medicine,
Sheffield Teaching Hospitals

BTS guidelines – 1999

NICE guidelines – 2006
Thorax 2000: 55; 210-218
– Sensitive TB – 4 drugs for 2 months
2 drugs for 4 months
– Resistant TB - 6 drugs for 24 months (second
line drugs are not so effective)
[Eng, Wales & NI 2004, 6.8% Isoniazid resistant, 1%
MDR TB (R to Isoniazid and rifampicin)]
Dpt. Infection and Tropical Medicine,
Sheffield Teaching Hospitals
Problems of TB therapy

Toxicity e.g. liver
 Multiple therapy
 Prolonged treatment
 Drug interactions e.g. anti HIV drugs
Dpt. Infection and Tropical Medicine,
Sheffield Teaching Hospitals
Compliance
– Treatment will not work if not taken
– DOTS (Directly Observed Therapy) if:
 Likely poor compliance
 MDRTB
Dpt. Infection and Tropical Medicine,
Sheffield Teaching Hospitals
Outcome

WHO target (1991)
– detect 70% infectious cases of TB and cure at
least 85% by 2005

Eng, Wales and NI
– Probably detect 70% cases infectious TB
– Cure rate uncertain

Among all TB patients with a known outcome the
proportion of cases that have completed treatment
– 79% in 2003
– 78% in 2002
– 79% in 2001
Dpt. Infection and Tropical Medicine,
Sheffield Teaching Hospitals
CDR 23 March 2006
Why failure?

Patient non compliance
– Deliberate
– Failure to understand e.g. language, culture
– Social e.g. alcohol
Patient movement e.g. ‘lost to follow up’
 Lack of medical/nursing support
 others

Dpt. Infection and Tropical Medicine,
Sheffield Teaching Hospitals
public health - avoiding
transmission

TB is statutorily notifiable disease
 Multidisciplinary approach – medical, TB nurses,
CCDC etc.


Identify and manage possible sources of infection and contacts
Considerations




treat as OP where possible
multi occupancy housing, social deprivation
negative pressure rooms in hospitals (limited facility)
beware transmission in OP setting e.g. waiting area
Dpt. Infection and Tropical Medicine,
Sheffield Teaching Hospitals
New challenges in TB
Dpt. Infection and Tropical Medicine,
Sheffield Teaching Hospitals
Challenges in TB

Anti TNF therapy (Eg infliximab, etanercept)
– May promote breakdown of granulomas and
reactivation of TB
– How to screen




Clinical history
CXR (? With induced sputum)
Skin testing
?? Value of gamma interferon tests
Dpt. Infection and Tropical Medicine,
Sheffield Teaching Hospitals
Challenges in TB
What will be the place of
Quantiferon and Elispot
type tests in clinical practice?
Dpt. Infection and Tropical Medicine,
Sheffield Teaching Hospitals
Clinical need for new and
better anti TB drugs
Dpt. Infection and Tropical Medicine,
Sheffield Teaching Hospitals

Objective - to lead to more effective shorter
course regimen
– Better pharmacokinetics
 longer half life
 better penetration to cavities
– Better activity
 kill TB in dormant phase
 Active against resistant strains
– Safer and easier
 Lack of interaction with anti HIV therapy
 Less toxic
– Low cost
Dpt. Infection and Tropical Medicine,
Sheffield Teaching Hospitals
Will there be new affordable
therapy for TB?

Global Alliance for TB Drug Development
 TB development drug discovery research
unit
– Astra Zenica
– Glaxo SmithKline
– Novartis

WHO links with pharma
 TB trials consortium (US CDC)
Dpt. Infection and Tropical Medicine,
Sheffield Teaching Hospitals
Will there be new affordable
therapy for TB?

Moxifloxacin
 TMC 207
 OPC-67683
 PA-824
 LL3858
Dpt. Infection and Tropical Medicine,
Sheffield Teaching Hospitals
Summary

TB is a challenging disease for the clinician
 Must have microbiology before starting
treatment – more rapid lab tests?
 Need to encourage compliance
 Need for multidisciplinary approach to
diagnosis and management and control
 Need shorter, better, cheap anti TB regimes
Dpt. Infection and Tropical Medicine,
Sheffield Teaching Hospitals